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IMA Newsletter #404

June 2010

2009-2010 Program

See http://www.ima.umn.edu/2009-2010/ for a full description of the 2009-2010 program on Complex Fluids and Complex Flows.

News and Notes
2010-2011 IMA Participating Institutions Conferences
IMA Events

IMA Annual Program Year Workshop

Natural Locomotion in Fluids and on Surfaces: Swimming, Flying, and Sliding

June 1-5, 2010

Organizers: Stephen Childress (New York University), Anette Peko Hosoi (Massachusetts Institute of Technology), William W. Schultz (University of Michigan), Jane Wang (Cornell University)

New Directions Short Course: New Mathematical Models in Economics and Finance

June 7-18, 2010

Organizers: Rene Carmona (Princeton University), Ivar Ekeland (University of British Columbia)

PI Summer Graduate Program

Computational Wave Propagation

June 7-25, 2010

Organizers: Gang Bao (Michigan State University), Jianliang Qian (Michigan State University)

IMA Workshop

Interdisciplinary Research Experience for Undergraduates

June 14 - July 16, 2010

Organizers: Laura Chihara (Carleton College), Karen Saxe (Macalester College), Paul Zorn (St. Olaf College)

IMA Workshop

Kickoff Workshop for Project MOSAIC

June 30 - July 2, 2010

Organizers: Daniel Kaplan (Macalester College)
Schedule

Tuesday, June 1

8:15am-9:15amRegistration and refreshments
bagels and cream cheese
EE/CS 3-176 W6.1-5.10
9:15am-9:30amWelcome to the IMAFadil Santosa (University of Minnesota)EE/CS 3-180 W6.1-5.10
9:30am-9:45amWelcome/last-minute announcementsStephen Childress (New York University)EE/CS 3-180 W6.1-5.10
9:45am-10:30amSubtleties in nature’s simplest form of locomotion: jet propulsion in squids and scallopsMark Denny (Stanford University)EE/CS 3-180 W6.1-5.10
10:30am-11:00amCoffeeEE/CS 3-176 W6.1-5.10
11:00am-11:45amSymmetry-breaking in small-scale locomotion: Synchronization and efficiency optimizationEric Lauga (University of California, San Diego)EE/CS 3-180 W6.1-5.10
11:45am-1:00pmLunch
Lunch Tutorial (starts at 1:00, lunch not provided)
EE/CS 3-180 W6.1-5.10
1:00pm-2:15pmTutorial: Introduction to locomotion at low and intermediate Reynolds numbers Stephen Childress (New York University)EE/CS 3-180 W6.1-5.10
2:15pm-3:00pmFrom individual to collective swimming dynamics of bacillus subtilisLuis H. Cisneros (University of Arizona)EE/CS 3-180 W6.1-5.10
3:00pm-3:30pmCoffeeEE/CS 3-176 W6.1-5.10
3:30pm-4:15pmIdealized modeling of planar fishlike swimming for motion control Scott David Kelly (University of North Carolina - Charlotte)EE/CS 3-180 W6.1-5.10
4:15pm-4:45pmGroup Photo W6.1-5.10

Wednesday, June 2

8:30am-9:00amCoffee
fruit and yogurt
EE/CS 3-176 W6.1-5.10
9:00am-9:45amPoster Sound Bites Gordon Joseph Berman (Princeton University)
Kenny Breuer (Brown University)
Randy H. Ewoldt (University of Minnesota)
Hermes Gadêlha (University of Oxford)
Jifeng Hu (University of Minnesota)
Pieter Jan Antoon Janssen (University of Wisconsin)
Arshad Kudrolli (Clark University)
Amy Lang (University of Alabama)
Ronald G. Larson (University of Michigan)
Enkeleida Lushi (New York University)
Hassan Masoud (Georgia Institute of Technology)
Hoa Nguyen (Tulane University)
Clara O'Farrell (California Institute of Technology)
Sarah Olson (Tulane University)
EE/CS 3-180 W6.1-5.10
9:45am-10:30amTradeoffs between swimming and feeding: The curious case of the upside down jellyfishLaura Ann Miller (University of North Carolina)EE/CS 3-180 W6.1-5.10
10:30am-11:00amCoffeeEE/CS 3-176 W6.1-5.10
11:00am-11:45amHow flying insects keep stable, up-right, and on-course Leif Gibbens Ristroph (Cornell University)EE/CS 3-180 W6.1-5.10
11:45am-1:00pmLunch
Lunch Tutorial (starts at 1:00, lunch not provided)
EE/CS 3-180 W6.1-5.10
1:00pm-2:15pmTutorial: Introduction to insect flightJane Wang (Cornell University)EE/CS 3-180 W6.1-5.10
2:15pm-3:00pmAlgorithms for nonlinear analysis, optimization, and control of locomotionRuss Tedrake (Massachusetts Institute of Technology)EE/CS 3-180 W6.1-5.10
3:00pm-3:30pmCoffeeEE/CS 3-176 W6.1-5.10
3:30pm-4:15pmUsing vortices for locomotionJohn O. Dabiri (California Institute of Technology)EE/CS 3-180 W6.1-5.10
4:15pm-5:15pm12-Minute Contributed TalksEE/CS 3-180 W6.1-5.10
Numerical simulations of a free squirmer in a viscoelastic fluid Luca Brandt (Royal Institute of Technology (KTH))
Low-Reynolds-number swimming near walls and free surfacesDarren G. Crowdy (Imperial College London)
Transport in suspensions of swimming organismsMichael D. Graham (University of Wisconsin)
Paramecium swimming near a wall Sunghwan (Sunny) Jung (Virginia Polytechnic Institute and State University)

Thursday, June 3

8:30am-9:00amCoffee
bagels and cream cheese
EE/CS 3-176 W6.1-5.10
9:00am-9:45amPoster Sound Bites Acmae El Yacoubi (Cornell University)
Daniel Ivan Goldman (Georgia Institute of Technology)
Zhi (George) Lin (University of Minnesota)
Yizhar Or (Technion-Israel Institute of Technology)
Neelesh A. Patankar (Northwestern University)
Jifeng Peng (University of Alaska)
Henry Shum (University of Oxford)
Saverio Eric Spagnolie (University of California, San Diego)
Wanda Strychalski (University of California, Davis)
Susan S. Suarez (Cornell University)
Daniel See-Wai Tam (Massachusetts Institute of Technology)
Sheng Xu (Southern Methodist University)
Jeannette Yen (Georgia Institute of Technology)
EE/CS 3-180 W6.1-5.10
9:45am-10:30amEffects of ambient water flow on locomotion Mimi Koehl (University of California, Berkeley)EE/CS 3-180 W6.1-5.10
10:30am-11:00amCoffeeEE/CS 3-176 W6.1-5.10
11:00am-11:45amEmergence of coherent structures and large-scale flows in biologically active suspensions David Saintillan (University of Illinois at Urbana-Champaign)EE/CS 3-180 W6.1-5.10
11:45am-1:00pmLunch
Lunch Tutorial (starts at 1:00, lunch not provided)
EE/CS 3-180 W6.1-5.10
1:00pm-2:15pmTutorial: Introduction to fish locomotion William W. Schultz (University of Michigan)EE/CS 3-180 W6.1-5.10
2:15pm-3:15pm12-Minute Contributed TalksEE/CS 3-180 W6.1-5.10
A unified framework for inviscid and viscous simulations of biolocomotionJeff D. Eldredge (University of California, Los Angeles)
Experimental studies to reveal the boundary layer control mechanisms of shark skinAmy Lang (University of Alabama)
Leading-edge vortices elevate lift of autorotating plant seedsDavid Lentink (Wageningen University and Research Center)
3:15pm-3:30pmCoffeeEE/CS 3-176 W6.1-5.10
3:30pm-4:15pmOptimal coordinate choice for locomoting systemsHowie Choset (Carnegie Mellon University)EE/CS 3-180 W6.1-5.10
4:15pm-6:15pmPoster Session and Reception
Poster submissions welcome from all participants
Instructions
Lind Hall 400 W6.1-5.10
Reconstructing the behavior of terrestrial fruit fliesGordon Joseph Berman (Princeton University)
Synchronization of flagella and cilia through hydrodynamic interactionsKenny Breuer (Brown University)
A kinetic theory for suspensions of micoswimmersZhenlu Cui (Fayetteville State University)
Computational study of the interaction of free moving particles at intermediate Reynolds numbersAcmae El Yacoubi (Cornell University)
Helicobacter pylori (stomach bacterium) moves through mucus by reducing mucin viscoelasticity Randy H. Ewoldt (University of Minnesota)
Nonlinear instability in flagellar dynamics: a novel modulation mechanism in sperm migration? Hermes Gadêlha (University of Oxford)
Sensitive dependence of the motion of a legged robot on sand Daniel Ivan Goldman (Georgia Institute of Technology)
Inertial corrections to Darcy’s law for Hele-Shaw flowsAndong He (Pennsylvania State University)
Low Reynolds number swimming models of cell blebbing Jifeng Hu (University of Minnesota)
Qixuan Wang (University of Minnesota)
Flagellar bundlingPieter Jan Antoon Janssen (University of Wisconsin)
Collective diffusion of self-propelled rodsArshad Kudrolli (Clark University)
Experimental studies to reveal the boundary layer control mechanisms of shark skinAmy Lang (University of Alabama)
Swimming dynamics of a run-and-tumble bacterium with helical flagella Ronald G. Larson (University of Michigan)
A hydrodynamic model of biogenic mixingZhi (George) Lin (University of Minnesota)
The turning-particle chemotaxis model in suspensions of micro-swimmersEnkeleida Lushi (New York University)
Low Reynolds number aerodynamics of flexible flapping wings at resonanceHassan Masoud (Georgia Institute of Technology)
Fluid dynamics of phytoplankton with spines in linear shear flowHoa Nguyen (Tulane University)
Lagrangian coherent structures in the wake on an anguilliform swimmerClara O'Farrell (California Institute of Technology)
An integrative model of sperm motilitySarah Olson (Tulane University)
Dynamic and stability of low-Reynolds-number swimming near a wallYizhar Or (Technion-Israel Institute of Technology)
Drag-thrust decomposition and optimality in swimming Neelesh A. Patankar (Northwestern University)
How does muscle forcing lead to translational motion during undulatory swimming? Neelesh A. Patankar (Northwestern University)
A vortex sheet model of jellyfish swimmingJifeng Peng (University of Alaska)
Fruit flies modulate passive wing pitching to generate in-flight turnsLeif Gibbens Ristroph (Cornell University)
Instability regimes in flowing suspensions of swimming micro-organismsDavid Saintillan (University of Illinois at Urbana-Champaign)
Shear induced three-dimensional swimming characteristics of Dunaliella Primolecta in a microfluidic channelJian Sheng (University of Minnesota)
Hydrodynamic surface interactions of Escherichia coli at high concentrationJian Sheng (University of Minnesota)
A boundary element approach to bacteria approaching boundariesHenry Shum (University of Oxford)
Swimming at low and intermediate Reynolds numberSaverio Eric Spagnolie (University of California, San Diego)
A computational model of bleb formationWanda Strychalski (University of California, Davis)
Distinct Ca2+ signaling pathways turn mouse sperm in opposite directionsSusan S. Suarez (Cornell University)
Dynamics of passive flexible wingsDaniel See-Wai Tam (Massachusetts Institute of Technology)
Coupling the Newton dynamics and aerodynamics of insect flight in the immersed interface methodSheng Xu (Southern Methodist University)
Kinematics of various swimming modes in Antarctic krillJeannette Yen (Georgia Institute of Technology)

Friday, June 4

8:30am-9:00amCoffee
fruit and yogurt
EE/CS 3-176 W6.1-5.10
9:00am-9:15amThe wet-dog shake David Hu (Georgia Institute of Technology)EE/CS 3-180 W6.1-5.10
9:15am-9:30amAspects of human sperm motility: Observation and theoryEamonn Andrew Gaffney (University of Oxford)EE/CS 3-180 W6.1-5.10
9:30am-9:45amControllability by the shape of a low Reynolds number swimmerMarius Tucsnak (Université de Nancy I (Henri Poincaré))EE/CS 3-180 W6.1-5.10
9:45am-10:30amLiving in a turbulent world: Interactions between fishes and eddiesAline J. Cotel (University of Michigan)
Paul W. Webb (University of Michigan)
EE/CS 3-180 W6.1-5.10
10:30am-11:00amCoffeeEE/CS 3-176 W6.1-5.10
11:00am-11:45amLamprey locomotion: An integrative muscle mechanics - fluid dynamics model Lisa J. Fauci (Tulane University)EE/CS 3-180 W6.1-5.10
11:45am-2:15pmLunch W6.1-5.10
2:15pm-3:00pm12-Minute Contributed TalksEE/CS 3-180 W6.1-5.10
The balance between drag and thrust in undulatory propulsion and implications on balistiform and gymnotiform locomotion Neelesh A. Patankar (Northwestern University)
Unsolved problems in the locomotion of mammalian spermSusan S. Suarez (Cornell University)
Performance of ray fins in fish locomotionQiang Zhu (University of California, San Diego)
3:00pm-3:30pmCoffeeEE/CS 3-176 W6.1-5.10
3:30pm-4:15pmSnakes crawling and worms pushing on surfacesMichael J. Shelley (New York University)EE/CS 3-180 W6.1-5.10
4:15pm-5:00pmPanel Discussion/Lively Debate EE/CS 3-180 W6.1-5.10
6:30pm-8:30pmWorkshop dinner at Caspian BistroCaspian Bistro
2418 University Ave SE
Minneapolis, MN 55414
612-623-1133
W6.1-5.10

Saturday, June 5

8:30am-9:00amCoffee
bagels and cream cheese
EE/CS 3-176 W6.1-5.10
9:00am-9:45amSwimming and flapping in vortex wakes Silas Alben (Georgia Institute of Technology)EE/CS 3-180 W6.1-5.10
9:45am-10:30amWinged aquatic locomotion for high energetic efficiency through vortex controlFrank E. Fish (West Chester University)EE/CS 3-180 W6.1-5.10
10:30am-11:00amCoffee EE/CS 3-176 W6.1-5.10
11:00am-12:00pm12-Minute Contributed TalksEE/CS 3-180 W6.1-5.10
Experiments and models reveal principles of locomotion of the sand-swimming sandfish lizard Daniel Ivan Goldman (Georgia Institute of Technology)
Stability of active suspensionsChristel Hohenegger (New York University)
Passive locomotion in unsteady flowsEva Kanso (University of Southern California)
Jet propulsion without inertiaSaverio Eric Spagnolie (University of California, San Diego)
12:00pm-12:15pmClosing remarksEE/CS 3-180 W6.1-5.10

Monday, June 7

8:15am-8:45amRegistration and coffee Lind Hall 400 ND6.7-18.10
8:30am-9:00amCoffee Michigan State University
Wells Hall B102
PISG6.7-25.10
8:45am-9:00amWelcome to the IMAFadil Santosa (University of Minnesota)Lind Hall 305 ND6.7-18.10
9:00am-10:00amContemporary asymptotic methodsRobert Burridge (Massachusetts Institute of Technology)Michigan State University
Wells Hall B102
PISG6.7-25.10
9:00am-10:30amMonge-Kantorovich optimal transport problemGuillaume Carlier (Université de Paris-Dauphine)Lind Hall 305 ND6.7-18.10
10:00am-10:15amBreak PISG6.7-25.10
10:15am-11:15amContemporary asymptotic methods (continued)Robert Burridge (Massachusetts Institute of Technology)Michigan State University
Wells Hall B102
PISG6.7-25.10
10:30am-11:00amCoffee break Lind Hall 400 ND6.7-18.10
11:00am-12:30pmEnergy and emissions markets, and the existing cap-and-trade schemesRene Carmona (Princeton University)Lind Hall 305 ND6.7-18.10
11:15am-11:30amBreak PISG6.7-25.10
11:30am-12:30pmDis/Q&A Michigan State University
Wells Hall B102
PISG6.7-25.10
12:30pm-2:00pmLunch PISG6.7-25.10
12:30pm-2:00pmLunch ND6.7-18.10
2:00pm-3:30pmSimulations of realistic EU ETS models
joint work with U. Cetin & P. Barrieu (London School of Economics)
Max Fehr (London School of Economics and Political Science)Lind Hall 305 ND6.7-18.10
2:00pm-3:00pmContemporary asymptotic methodsJianliang Qian (Michigan State University)Michigan State University
Wells Hall B102
PISG6.7-25.10
3:00pm-3:15pmBreak PISG6.7-25.10
3:15pm-4:15pmLec/Lab/DisMichigan State University
Wells Hall B102
PISG6.7-25.10
3:30pm-3:40pmGroup photo ND6.7-18.10
4:15pm-5:00pmOffice Hours PISG6.7-25.10

Tuesday, June 8

8:30am-9:00amCoffee Lind Hall 400 ND6.7-18.10
8:30am-9:00amCoffee Michigan State University
Wells Hall B102
PISG6.7-25.10
9:00am-10:00amContemporary asymptotic methods (continued)Robert Burridge (Massachusetts Institute of Technology)Michigan State University
Wells Hall B102
PISG6.7-25.10
9:00am-10:30amStrictly convex transportation costsGuillaume Carlier (Université de Paris-Dauphine)Lind Hall 305 ND6.7-18.10
10:00am-10:15amBreak PISG6.7-25.10
10:15am-11:15amContemporary asymptotic methods (continued)Robert Burridge (Massachusetts Institute of Technology)Michigan State University
Wells Hall B102
PISG6.7-25.10
10:30am-11:00amCoffee breakLind Hall 400 ND6.7-18.10
11:00am-12:30pmDiscrete time competitive equilibrium models for cap-and-trade schemes and the carbon taxRene Carmona (Princeton University)Lind Hall 305 ND6.7-18.10
11:15am-11:30amBreak PISG6.7-25.10
11:30am-12:30pmDis/Q&A Michigan State University
Wells Hall B102
PISG6.7-25.10
12:30pm-2:00pmLunch PISG6.7-25.10
12:30pm-2:00pmLunch ND6.7-18.10
2:00pm-3:00pmContemporary asymptotic methods (continued)Jianliang Qian (Michigan State University)Michigan State University
Wells Hall B102
PISG6.7-25.10
2:00pm-3:30pmImplementation of a simple model: first example Rene Carmona (Princeton University)
Max Fehr (London School of Economics and Political Science)
Lind Hall 305 ND6.7-18.10
3:00pm-3:15pmBreak PISG6.7-25.10
3:15pm-4:15pmLec/Lab/DisMichigan State University
Wells Hall B102
PISG6.7-25.10
4:15pm-5:00pmOffice Hours PISG6.7-25.10
6:30pm-8:30amDinnerTBA PISG6.7-25.10

Wednesday, June 9

8:30am-9:00amCoffee Lind Hall 400 ND6.7-18.10
8:30am-9:00amCoffee Michigan State University
Wells Hall B102
PISG6.7-25.10
9:00am-10:00amContemporary asymptotic methods (continued)Robert Burridge (Massachusetts Institute of Technology)Michigan State University
Wells Hall B102
PISG6.7-25.10
9:00am-10:30amThe case cost=distanceGuillaume Carlier (Université de Paris-Dauphine)Lind Hall 305 ND6.7-18.10
10:00am-10:15amBreak PISG6.7-25.10
10:15am-11:15amContemporary asymptotic methods (continued)Robert Burridge (Massachusetts Institute of Technology)Michigan State University
Wells Hall B102
PISG6.7-25.10
10:30am-11:00amCoffee breakLind Hall 400 ND6.7-18.10
11:00am-12:30pmMathematical models for allocation mechanisms and cost distributionRene Carmona (Princeton University)Lind Hall 305 ND6.7-18.10
11:15am-11:30amBreak PISG6.7-25.10
11:30am-12:30pmDis/Q&A Michigan State University
Wells Hall B102
PISG6.7-25.10
12:30pm-2:00pmLunch PISG6.7-25.10
12:30pm-2:00pmLunch ND6.7-18.10
2:00pm-3:00pmContemporary asymptotic methods (continued)Jianliang Qian (Michigan State University)Michigan State University
Wells Hall B102
PISG6.7-25.10
2:00pm-3:30pmImplementation of a simple model: second example Rene Carmona (Princeton University)
Max Fehr (London School of Economics and Political Science)
Lind Hall 305 ND6.7-18.10
3:00pm-3:15pmBreak PISG6.7-25.10
3:15pm-4:15pmLec/Lab/DisMichigan State University
Wells Hall B102
PISG6.7-25.10
4:15pm-5:00pmOffice Hours PISG6.7-25.10

Thursday, June 10

8:30am-9:00amCoffee Lind Hall 400 ND6.7-18.10
8:30am-9:00amCoffee Michigan State University
Wells Hall B102
PISG6.7-25.10
9:00am-10:00amContemporary asymptotic methods (continued)Robert Burridge (Massachusetts Institute of Technology)Michigan State University
Wells Hall B102
PISG6.7-25.10
9:00am-10:30amEconomic applications of optimal transportGuillaume Carlier (Université de Paris-Dauphine)Lind Hall 305 ND6.7-18.10
10:00am-10:15amBreak PISG6.7-25.10
10:15am-11:15amContemporary asymptotic methods (continued)Robert Burridge (Massachusetts Institute of Technology)Michigan State University
Wells Hall B102
PISG6.7-25.10
10:30am-11:00amCoffee breakLind Hall 400 ND6.7-18.10
11:00am-12:30pmDiscrete time competitive equilibrium models for cap-and-trade schemes and the clean development mechanismRene Carmona (Princeton University)Lind Hall 305 ND6.7-18.10
11:15am-11:30amBreak PISG6.7-25.10
11:30am-12:30pmDis/Q&A Michigan State University
Wells Hall B102
PISG6.7-25.10
12:30pm-2:00pmLunch PISG6.7-25.10
12:30pm-2:00pmLunch ND6.7-18.10
2:00pm-3:00pmContemporary asymptotic methods (continued)Jianliang Qian (Michigan State University)Michigan State University
Wells Hall B102
PISG6.7-25.10
2:00pm-3:30pmNon-constant discount rates, time inconsistency, and the golden ruleIvar Ekeland (University of British Columbia)Lind Hall 305 ND6.7-18.10
3:00pm-3:15pmBreak PISG6.7-25.10
3:15pm-4:15pmLec/Lab/DisMichigan State University
Wells Hall B102
PISG6.7-25.10
4:15pm-5:00pmOffice Hours PISG6.7-25.10
5:00pm-6:00pmAfternoon games (tentative) PISG6.7-25.10

Friday, June 11

8:30am-9:00amCoffee Lind Hall 400 ND6.7-18.10
8:30am-9:00amCoffee Michigan State University
Wells Hall B102
PISG6.7-25.10
9:00am-10:00amContemporary asymptotic methods (continued)Robert Burridge (Massachusetts Institute of Technology)Michigan State University
Wells Hall B102
PISG6.7-25.10
9:00am-10:30amCongested transportGuillaume Carlier (Université de Paris-Dauphine)Lind Hall 305 ND6.7-18.10
10:00am-10:15amBreak PISG6.7-25.10
10:15am-11:15amContemporary asymptotic methods (continued)Robert Burridge (Massachusetts Institute of Technology)Michigan State University
Wells Hall B102
PISG6.7-25.10
10:30am-11:00amCoffee breakLind Hall 400 ND6.7-18.10
11:00am-12:30pmStochastic optimization and first continuous time models of cap-and-trade schemesRene Carmona (Princeton University)Lind Hall 305 ND6.7-18.10
11:15am-11:30amBreak PISG6.7-25.10
11:30am-12:30pmDis/Q&A Michigan State University
Wells Hall B102
PISG6.7-25.10
12:30pm-2:00pmLunch PISG6.7-25.10
12:30pm-2:00pmLunch ND6.7-18.10
2:00pm-3:00pmContemporary asymptotic methods (continued)Jianliang Qian (Michigan State University)Michigan State University
Wells Hall B102
PISG6.7-25.10
2:00pm-3:30pmThe Merton problem with hyperbolic discountingIvar Ekeland (University of British Columbia)Lind Hall 305 ND6.7-18.10
3:00pm-3:15pmBreak PISG6.7-25.10
3:15pm-4:15pmLec/Lab/DisMichigan State University
Wells Hall B102
PISG6.7-25.10
4:15pm-5:00pmOffice Hours PISG6.7-25.10

Saturday, June 12

All DayNo scheduled activity PISG6.7-25.10
All DayNo scheduled activity. ND6.7-18.10

Sunday, June 13

All DayNo scheduled activity PISG6.7-25.10
All DayNo scheduled activity. ND6.7-18.10

Monday, June 14

8:30am-9:00amCoffee Lind Hall 400 ND6.7-18.10
8:30am-9:00amRegistration and coffeeLind Hall 400 SW6.14-7.16.10
8:30am-9:00amCoffee Michigan State University
Wells Hall B102
PISG6.7-25.10
9:00am-9:15amWelcome to the IMAFadil Santosa (University of Minnesota)Lind Hall 409 SW6.14-7.16.10
9:00am-10:00amNumerics for full wavesJean-Claude Nédélec (École Polytechnique)Michigan State University
Wells Hall B102
PISG6.7-25.10
9:00am-10:30amBinary martingales and option pricing: 1) Reduced form models; 2) Perturbation methodsRene Carmona (Princeton University)Lind Hall 305 ND6.7-18.10
9:15am-9:55amIntro to Project 1: Pursuit-evasion games with multiple pursuers (all groups) Volkan Isler (University of Minnesota)Lind Hall 409 SW6.14-7.16.10
9:55am-10:35amIntro to Project 2: Long-wave models for elastohydrodynamic instabilities (all groups)Daniel Flath (Macalester College)Lind Hall 409 SW6.14-7.16.10
10:00am-10:15amBreak PISG6.7-25.10
10:15am-11:15amNumerics for full waves (continued)Jean-Claude Nédélec (École Polytechnique)Michigan State University
Wells Hall B102
PISG6.7-25.10
10:30am-11:00amCoffee breakLind Hall 400 ND6.7-18.10
10:35am-11:00amBreakLind Hall 400 SW6.14-7.16.10
11:00am-11:40amIntro to Project 3: Hybrid linear modeling (all groups)Gilad Lerman (University of Minnesota)Lind Hall 409 SW6.14-7.16.10
11:00am-12:30pmStochastic target problems and viscosity solutionsNizar Touzi (École Polytechnique)Lind Hall 305 ND6.7-18.10
11:15am-11:30amBreak PISG6.7-25.10
11:30am-12:30pmDis/Q&A Michigan State University
Wells Hall B102
PISG6.7-25.10
11:40am-12:00pmAnnouncementsLind Hall 409 SW6.14-7.16.10
12:00pm-1:00pmLunch at the IMA, getting acquainted SW6.14-7.16.10
12:30pm-2:00pmLunch PISG6.7-25.10
12:30pm-3:30pmLunch ND6.7-18.10
1:00pm-4:00pmGroups meet separately with faculty advisors and mentorsLind Hall 400 SW6.14-7.16.10
2:00pm-3:00pmNumerics for full waves (continued)Jean-Claude Nédélec (École Polytechnique)Michigan State University
Wells Hall B102
PISG6.7-25.10
3:00pm-3:15pmBreak PISG6.7-25.10
3:15pm-4:15pmLec/Lab/DisMichigan State University
Wells Hall B102
PISG6.7-25.10
3:30pm-5:00pmMartingale representation theorem for the G-expectationJianfeng Zhang (University of Southern California)Lind Hall 305 ND6.7-18.10
4:15pm-5:00pmOffice Hours PISG6.7-25.10

Tuesday, June 15

All DayWork all day on projects. Lind Hall 400 SW6.14-7.16.10
8:30am-9:00amCoffee Lind Hall 400 ND6.7-18.10
8:30am-9:00amCoffee Michigan State University
Wells Hall B102
PISG6.7-25.10
9:00am-10:00amNumerics for full wavesGang Bao (Michigan State University)Michigan State University
Wells Hall B102
PISG6.7-25.10
9:00am-10:30amSecond order stochastic target problemsNizar Touzi (École Polytechnique)Lind Hall 305 ND6.7-18.10
10:00am-10:15amBreak PISG6.7-25.10
10:15am-11:15amNumerics for full waves (continued)Gang Bao (Michigan State University)Michigan State University
Wells Hall B102
PISG6.7-25.10
10:30am-11:00amCoffee breakLind Hall 400 ND6.7-18.10
11:00am-12:30pmSingular BSDEs appearing in cap-and-trade modelsRene Carmona (Princeton University)Lind Hall 305 ND6.7-18.10
11:15am-11:30amBreak PISG6.7-25.10
11:30am-12:30pmDis/Q&A Michigan State University
Wells Hall B102
PISG6.7-25.10
12:30pm-2:00pmLunch PISG6.7-25.10
12:30pm-3:30pmLunch ND6.7-18.10
2:00pm-3:00pmNumerics for full waves (continued)Jean-Claude Nédélec (École Polytechnique)Michigan State University
Wells Hall B102
PISG6.7-25.10
2:30pm-3:30pmStrict local martingale deflators and pricing American call-type optionsErhan Bayraktar (University of Michigan)Lind Hall 305 ND6.7-18.10
3:00pm-3:15pmBreak PISG6.7-25.10
3:15pm-4:15pmLec/Lab/DisMichigan State University
Wells Hall B102
PISG6.7-25.10
3:30pm-5:00pmDynamic oligopolies and differential games. IRonnie Sircar (Princeton University)Lind Hall 305 ND6.7-18.10
4:15pm-5:00pmOffice Hours PISG6.7-25.10

Wednesday, June 16

All DayWork on projects. Lind Hall 400Lind Hall 400 SW6.14-7.16.10
8:30am-9:00amCoffee Lind Hall 400 ND6.7-18.10
8:30am-9:00amCoffee Michigan State University
Wells Hall B102
PISG6.7-25.10
9:00am-10:00amNumerics for full waves (continued)Jean-Claude Nédélec (École Polytechnique)Michigan State University
Wells Hall B102
PISG6.7-25.10
9:00am-10:30amBackward stochastic differential equations and connection with semilinear PDEsNizar Touzi (École Polytechnique)Lind Hall 305 ND6.7-18.10
10:00am-10:15amBreak PISG6.7-25.10
10:15am-11:15amNumerics for full waves (continued)Jean-Claude Nédélec (École Polytechnique)Michigan State University
Wells Hall B102
PISG6.7-25.10
10:30am-11:00amCoffee breakLind Hall 400 ND6.7-18.10
11:00am-12:30pmGame theory, Nash equilibrium, and electricity prices with strategic market playersRene Carmona (Princeton University)Lind Hall 305 ND6.7-18.10
11:15am-11:30amBreak PISG6.7-25.10
11:30am-12:30pmDis/Q&A Michigan State University
Wells Hall B102
PISG6.7-25.10
12:30pm-2:00pmLunch PISG6.7-25.10
12:30pm-3:30pmLunch ND6.7-18.10
2:00pm-3:00pmNumerics for full waves (continued)Gang Bao (Michigan State University)Michigan State University
Wells Hall B102
PISG6.7-25.10
2:30pm-3:30pmEvaluating regulatory strategies for emmision abatement - An engineering approach Steven Bleiler (Portland State University)Lind Hall 305 ND6.7-18.10
3:00pm-3:15pmBreak PISG6.7-25.10
3:00pm-4:00pmSeminar - Modeling swarmsChad Michael Topaz (Macalester College)Lind Hall 409 SW6.14-7.16.10
3:15pm-4:15pmLec/Lab/DisMichigan State University
Wells Hall B102
PISG6.7-25.10
3:30pm-5:00pmOptimal switching problems and applications in energy financeMichael Ludkovski (University of California, Santa Barbara)Lind Hall 305 ND6.7-18.10
4:15pm-5:00pmOffice Hours PISG6.7-25.10
6:30pm-8:30pmGroup dinner at Kafe 421Kafe 421
421 14th Avenue SE
Minneapolis, MN 55414
612-623-4900
ND6.7-18.10

Thursday, June 17

All DayWork on projects. Lind Hall 400 SW6.14-7.16.10
8:30am-9:00amCoffee Lind Hall 400 ND6.7-18.10
8:30am-9:00amCoffee Michigan State University
Wells Hall B102
PISG6.7-25.10
9:00am-10:00amNumerics for full waves (continued)Gang Bao (Michigan State University)Michigan State University
Wells Hall B102
PISG6.7-25.10
9:00am-10:30amSecond order backward stochastic differential equations and connection with fully nonlinear PDEsNizar Touzi (École Polytechnique)Lind Hall 305 ND6.7-18.10
10:00am-10:15amBreak PISG6.7-25.10
10:15am-11:15amNumerics for full waves (continued)Gang Bao (Michigan State University)Michigan State University
Wells Hall B102
PISG6.7-25.10
10:30am-11:00amCoffee breakLind Hall 400 ND6.7-18.10
11:00am-12:30pmStochastic games: Pontryagin maximum principle and the Isaacs conditionsRene Carmona (Princeton University)Lind Hall 305 ND6.7-18.10
11:15am-11:30amBreak PISG6.7-25.10
11:30am-12:30pmDis/Q&A Michigan State University
Wells Hall B102
PISG6.7-25.10
12:30pm-2:00pmLunch PISG6.7-25.10
12:30pm-3:30pmLunch ND6.7-18.10
2:00pm-3:00pmNumerics for full waves (continued)Jean-Claude Nédélec (École Polytechnique)Michigan State University
Wells Hall B102
PISG6.7-25.10
3:00pm-3:15pmBreak PISG6.7-25.10
3:00pm-6:00pmPizza and Movie (Amount due will be announced at a later time)
Social outing leader - Fadil Santosa
Lind Hall 409 SW6.14-7.16.10
3:15pm-4:15pmLec/Lab/DisMichigan State University
Wells Hall B102
PISG6.7-25.10
3:30pm-5:00pmDynamic oligopolies and differential games. IIRonnie Sircar (Princeton University)Lind Hall 305 ND6.7-18.10
4:15pm-5:00pmOffice Hours PISG6.7-25.10

Friday, June 18

All DayWork on projects. Lind Hall 400 SW6.14-7.16.10
8:30am-9:00amCoffee Lind Hall 400 ND6.7-18.10
8:30am-9:00amCoffee Michigan State University
Wells Hall B102
PISG6.7-25.10
9:00am-10:00amNumerics for full waves (continued)Jean-Claude Nédélec (École Polytechnique)Michigan State University
Wells Hall B102
PISG6.7-25.10
9:00am-10:30amNumerical methods for BSDEs and applicationsNizar Touzi (École Polytechnique)Lind Hall 305 ND6.7-18.10
10:00am-10:15amBreak PISG6.7-25.10
10:15am-11:15amNumerics for full waves (continued)Gang Bao (Michigan State University)Michigan State University
Wells Hall B102
PISG6.7-25.10
10:30am-11:00amCoffee breakLind Hall 400 ND6.7-18.10
11:00am-12:30pmExamples of linear-quadratic stochastic games in environmental financeRene Carmona (Princeton University)Lind Hall 305 ND6.7-18.10
11:15am-11:30amBreak PISG6.7-25.10
11:30am-12:30pmDis/Q&A Michigan State University
Wells Hall B102
PISG6.7-25.10
12:30pm-2:00pmLunch PISG6.7-25.10
2:00pm-3:00pmNumerics for full waves (continued)Gang Bao (Michigan State University)Michigan State University
Wells Hall B102
PISG6.7-25.10
3:00pm-3:15pmBreak PISG6.7-25.10
3:00pm-4:30pmEach group makes progress reports Lind Hall 409 SW6.14-7.16.10
3:15pm-4:15pmLec/Lab/DisMichigan State University
Wells Hall B102
PISG6.7-25.10
4:15pm-5:00pmOffice Hours PISG6.7-25.10

Saturday, June 19

All DayNo scheduled activity PISG6.7-25.10
All DayNo scheduled activity. SW6.14-7.16.10

Sunday, June 20

All DayNo scheduled activity PISG6.7-25.10
All DayNo scheduled activity. SW6.14-7.16.10

Monday, June 21

All DayWork all day on projects. Lind Hall 400 SW6.14-7.16.10
8:30am-9:00amCoffee Michigan State University
Wells Hall B102
PISG6.7-25.10
9:00am-10:00amTalk Bernardo Cockburn (University of Minnesota)Michigan State University
Wells Hall B102
PISG6.7-25.10
10:00am-10:10amBreak PISG6.7-25.10
10:10am-11:10amTalk John Schotland (University of Pennsylvania)Michigan State University
Wells Hall B102
PISG6.7-25.10
11:10am-11:20amBreak PISG6.7-25.10
11:20am-12:20pmTalkDavid C. Dobson (University of Utah)Michigan State University
Wells Hall B102
PISG6.7-25.10
12:20pm-2:00pmLunch PISG6.7-25.10
2:00pm-3:00pmTalk Jeffrey Rauch (University of Michigan)Michigan State University
Wells Hall B102
PISG6.7-25.10
3:00pm-3:10pmBreak PISG6.7-25.10
3:10pm-4:10pmTalk Jingfang Huang (University of North Carolina)Michigan State University
Wells Hall B102
PISG6.7-25.10
4:10pm-5:00pmDis/Q&A/OH Michigan State University
Wells Hall B102
PISG6.7-25.10

Tuesday, June 22

All DayWork all day on projects. Lind Hall 400 SW6.14-7.16.10
8:30am-9:00amCoffee Michigan State University
Wells Hall B102
PISG6.7-25.10
9:00am-10:00amTalk Thomas Hagstrom (Southern Methodist University)Michigan State University
Wells Hall B102
PISG6.7-25.10
10:00am-10:10amBreak PISG6.7-25.10
10:10am-11:10amTalk Li-Tien Cheng (University of California, San Diego)Michigan State University
Wells Hall B102
PISG6.7-25.10
11:10am-11:20amBreak PISG6.7-25.10
11:20am-12:30pmDis/Q&A Michigan State University
Wells Hall B102
PISG6.7-25.10
12:30pm-2:00pmLunch PISG6.7-25.10
2:00pm-3:00pmTalk Shingyu Leung (Hong Kong University of Science and Technology)Michigan State University
Wells Hall B102
PISG6.7-25.10
3:00pm-3:10pmBreak PISG6.7-25.10
3:10pm-4:10pmTalk Peijun Li (Purdue University)Michigan State University
Wells Hall B102
PISG6.7-25.10
4:10pm-5:00pmDis/Q&A/OH Michigan State University
Wells Hall B102
PISG6.7-25.10

Wednesday, June 23

All DayWork on projects. Lind Hall 400Lind Hall 400 SW6.14-7.16.10
8:30am-9:00amCoffee Michigan State University
Wells Hall B102
PISG6.7-25.10
9:00am-10:00amGroup disMichigan State University
Wells Hall B102
PISG6.7-25.10
10:00am-10:10amBreak PISG6.7-25.10
10:10am-11:10amTeam work Michigan State University
Wells Hall B102
PISG6.7-25.10
11:10am-11:20amBreak PISG6.7-25.10
11:20am-12:30pmQ&A Michigan State University
Wells Hall B102
PISG6.7-25.10
12:30pm-2:00pmLunch PISG6.7-25.10
2:00pm-3:00pmGroup disMichigan State University
Wells Hall B102
PISG6.7-25.10
3:00pm-4:00pmSeminar - Snail robots, adhesion, and complex fluidsRandy H. Ewoldt (University of Minnesota)Lind Hall 409 SW6.14-7.16.10
3:00pm-3:10pmBreak PISG6.7-25.10
3:10pm-4:10pmTeam work Michigan State University
Wells Hall B102
PISG6.7-25.10
4:10pm-5:00pmOffice Hours PISG6.7-25.10

Thursday, June 24

All DayWork on projects. Lind Hall 400 SW6.14-7.16.10
8:30am-9:00amCoffee Michigan State University
Wells Hall B102
PISG6.7-25.10
9:00am-10:00amTalk Ya Yan Lu (City University of Hong Kong)Michigan State University
Wells Hall B102
PISG6.7-25.10
10:00am-10:10amBreak PISG6.7-25.10
10:10am-11:10amTalk Balasubramaniam Shanker (Michigan State University)Michigan State University
Wells Hall B102
PISG6.7-25.10
11:10am-11:20amBreak PISG6.7-25.10
11:20am-12:30pmDis/Q&A Michigan State University
Wells Hall B102
PISG6.7-25.10
12:30pm-2:00pmLunch PISG6.7-25.10
2:00pm-3:00pmTalk Songming Hou (Louisiana Tech University)Michigan State University
Wells Hall B102
PISG6.7-25.10
3:00pm-6:00pmSocial outing - Como Zoo/Conservatory (Please remember change for the bus)
Social outing leader - Daniel Flath
Como Zoo/
Conservatory
SW6.14-7.16.10
3:00pm-3:10pmBreak PISG6.7-25.10
3:10pm-4:10pmTalk Yassine Boubendir (New Jersey Institute of Technology)Michigan State University
Wells Hall B102
PISG6.7-25.10
4:10pm-5:00pmDis/Q&A/OH Michigan State University
Wells Hall B102
PISG6.7-25.10

Friday, June 25

All DayWork on projects. Lind Hall 400 SW6.14-7.16.10
8:30am-9:00amCoffee Michigan State University
Wells Hall B102
PISG6.7-25.10
9:00am-10:00amStudent presentationsMichigan State University
Wells Hall B102
PISG6.7-25.10
10:00am-10:10amBreak PISG6.7-25.10
10:10am-11:10amStudent presentationsMichigan State University
Wells Hall B102
PISG6.7-25.10
11:10am-11:20amBreak PISG6.7-25.10
11:20am-12:30pmStudent presentationsMichigan State University
Wells Hall B102
PISG6.7-25.10
12:30pm-2:00pmLunch PISG6.7-25.10
2:00pm-3:00pmStudent presentationsMichigan State University
Wells Hall B102
PISG6.7-25.10
3:00pm-4:30pmEach group makes progress reports Lind Hall 409 SW6.14-7.16.10
3:00pm-3:10pmBreak PISG6.7-25.10
3:10pm-4:10pmStudent presentationsMichigan State University
Wells Hall B102
PISG6.7-25.10
4:10pm-5:00pmWrap-upMichigan State University
Wells Hall B102
PISG6.7-25.10

Saturday, June 26

All DayNo scheduled activity. SW6.14-7.16.10

Sunday, June 27

All DayNo scheduled activity. SW6.14-7.16.10

Monday, June 28

All DayWork all day on projects. Lind Hall 400 SW6.14-7.16.10

Tuesday, June 29

All DayWork all day on projects. Lind Hall 400 SW6.14-7.16.10

Wednesday, June 30

All DayWork on projects. Lind Hall 400Lind Hall 400 SW6.14-7.16.10
8:15am-8:45amRegistration and coffeeLind Hall 400 SW6.30-7.2.10
8:45am-9:00amIntroduction to the IMAFadil Santosa (University of Minnesota)Lind Hall 305 SW6.30-7.2.10
9:00am-9:45am Introduction to MOSAIC Daniel Kaplan (Macalester College)Lind Hall 305 SW6.30-7.2.10
9:45am-10:45amMOSAIC Curricula I (Randall Pruim, moderator)Christophe Golé (Smith College)
Eric Marland (Appalachian State University)
Randall Pruim (Calvin College)
Lind Hall 305 SW6.30-7.2.10
10:45am-11:15amBreakLind Hall 400 SW6.30-7.2.10
11:15am-12:15pmMOSAIC Curricula II Lind Hall 305 SW6.30-7.2.10
Saber Elaydi (Trinity University)
The Integration of … modeling, statistics, computation and calculus at East Tennessee State University Jeff Randall Knisley (East Tennessee State University)
moderatorRandall Pruim (Calvin College)
12:15pm-1:30pmLunch (independently) Local restaurants SW6.30-7.2.10
1:30pm-2:30pmIdentifying modeling concepts Daniel Kaplan (Macalester College)Lind Hall 305 SW6.30-7.2.10
2:30pm-3:00pmBreakLind Hall 400 SW6.30-7.2.10
3:00pm-4:00pmSeminar - Title:TBARichard P. McGehee (University of Minnesota)Lind Hall 409 SW6.14-7.16.10
3:00pm-4:00pmComputer packages and languages to support MOSAIC instructionRandall Pruim (Calvin College)EE/CS 3-180 SW6.30-7.2.10
4:00pm-4:30pmMOSAICS and Tiles I Lind Hall 305 SW6.30-7.2.10
moderatorNicholas Jon Horton (Smith College)
Automatic differentiation using MATLAB OOPRichard D. Neidinger (Davidson College)
Randomization based inferenceNathan Tintle (Hope College)
4:30pm-4:40pmGroup photo SW6.30-7.2.10
4:40pm-5:30pmMOSAICS and Tiles II Lind Hall 305 SW6.30-7.2.10
moderatorNicholas Jon Horton (Smith College)
Learning by investigation: A context for integrating statistics, mathematics, and computationJeff Randall Knisley (East Tennessee State University)
Randall Pruim (Calvin College)
6:30pm-9:30pmSocial activity: Saint Paul Saints game. Cars leave at 6:30. (Decent) ballpark food available at the game. SW6.30-7.2.10

Thursday, July 1

All DayWork on projects. Lind Hall 400 SW6.14-7.16.10
8:30am-9:00amCoffeeLind Hall 400 SW6.30-7.2.10
9:00am-9:45amIntroduction to concept inventoriesDaniel Kaplan (Macalester College)Lind Hall 305 SW6.30-7.2.10
9:45am-10:15amBrainstorming inventory problems Daniel Kaplan (Macalester College)Lind Hall 305 SW6.30-7.2.10
10:15am-10:30amBreakLind Hall 400 SW6.30-7.2.10
10:30am-11:15amMOSAIC computation Lind Hall 305 SW6.30-7.2.10
Simulate THAT! (15m)James Caristi (Valparaiso University)
moderatorNicholas Jon Horton (Smith College)
Keeping it R.E.A.L. (30m)Anthony Tongen (James Madison University)
11:15am-12:30pmModel eliciting activitiesRobert Claude delMas (University of Minnesota)Lind Hall 305 SW6.30-7.2.10
12:00pm-1:30pmLunch (independently) Local restaurants SW6.30-7.2.10
1:30pm-2:00pm Principles of assessmentAndrew Zieffler (University of Minnesota)Lind Hall 305 SW6.30-7.2.10
2:00pm-3:00pmLeading and M-CAST Lind Hall 305 SW6.30-7.2.10
A prototype M-CASTNicholas Jon Horton (Smith College)
A day at the lakeDaniel Kaplan (Macalester College)
moderatorEric Marland (Appalachian State University)
3:00pm-6:00pmSocial outing - Mill City Museum
(please bring \$10 - \$15 with you for entrance and transportation)
Social outing leader - Andrew Beveridge
Mill City Museum
704 South Second Street
Minneapolis, MN 55401
612-341-7555
SW6.14-7.16.10
3:00pm-3:15pmBreakLind Hall 400 SW6.30-7.2.10
3:15pm-3:45pmBrainstorming ideas for M-CASTSEric Marland (Appalachian State University)Lind Hall 305 SW6.30-7.2.10
3:45pm-4:30pmMOSAIC Curricula III Lind Hall 305 SW6.30-7.2.10
Statistical modeling for poetsVittorio Addona (Macalester College)
Applied calculus at MacalesterDaniel Kaplan (Macalester College)
4:30pm-5:00pmCreating Momentum: Where do we go from here? How do we get there?Eric Marland (Appalachian State University)Lind Hall 305 SW6.30-7.2.10
6:00pm-9:00pmSocial Activity: Open house at the Walker Art Center, dinner as arranged independently. SW6.30-7.2.10

Friday, July 2

All DayWork on projects. Lind Hall 400 SW6.14-7.16.10
8:30am-9:00amCoffeeLind Hall 400 SW6.30-7.2.10
9:00am-10:30amTeaching computation to support STEM studentsLind Hall 305 SW6.30-7.2.10
Literate, reproducible computationNicholas Jon Horton (Smith College)
R and Matlab at MacalesterDaniel Kaplan (Macalester College)
Python at CalvinRandall Pruim (Calvin College)
10:30am-10:45am BreakLind Hall 400 SW6.30-7.2.10
10:45am-12:00pmPanel discussion: Institutional opportunities and obstacles (Saber Elaydi, moderator)Olcay Akman (Illinois State University)
Saber Elaydi (Trinity University)
Jeff Randall Knisley (East Tennessee State University)
Eric Marland (Appalachian State University)
Michael Pearson (Mathematical Association of America (MAA))
Andrew Zieffler (University of Minnesota)
Lind Hall 305 SW6.30-7.2.10
12:00pm-12:15pmWrap-up and recommendations for further actionsDaniel Kaplan (Macalester College)Lind Hall 305 SW6.30-7.2.10
3:00pm-4:30pmEach group makes progress reports Lind Hall 409 SW6.14-7.16.10

Saturday, July 3

All DayNo scheduled activity. SW6.14-7.16.10

Sunday, July 4

All DayNo scheduled activity. SW6.14-7.16.10

Monday, July 5

All DayIndependence Day (observed). The IMA is closed.
All DayWork all day on projects. Lind Hall 400 SW6.14-7.16.10

Tuesday, July 6

All DayWork all day on projects. Lind Hall 400 SW6.14-7.16.10

Wednesday, July 7

All DayWork on projects. Lind Hall 400Lind Hall 400 SW6.14-7.16.10
3:00pm-4:00pmSeminar - Squishy and frozen interfaces: Instabilities and applicationsSatish Kumar (University of Minnesota)Lind Hall 409 SW6.14-7.16.10

Thursday, July 8

All DayWork on projects. Lind Hall 400 SW6.14-7.16.10
3:00pm-6:00pmSocial outing - St. Anthony Falls Laboratory Tour
Social outing leader - Kara Lee Maki
St. Anthony Falls Laboratory SW6.14-7.16.10

Friday, July 9

All DayWork on projects. Lind Hall 400 SW6.14-7.16.10
3:00pm-4:30pmEach group makes progress reports Lind Hall 409 SW6.14-7.16.10

Saturday, July 10

All DayNo scheduled activity. SW6.14-7.16.10

Sunday, July 11

All DayNo scheduled activity. SW6.14-7.16.10

Monday, July 12

All DayWork all day on projects. Lind Hall 400 SW6.14-7.16.10

Tuesday, July 13

All DayWork all day on projects. Lind Hall 400 SW6.14-7.16.10

Wednesday, July 14

All DayWork on projects. Lind Hall 400Lind Hall 400 SW6.14-7.16.10
3:00pm-4:00pmSeminar - Title:TBADaniel Spirn (University of Minnesota)Lind Hall 409 SW6.14-7.16.10

Thursday, July 15

All DayWork on projects. Lind Hall 400 SW6.14-7.16.10
3:00pm-6:00pmSocial outing - Canoe at Calhoun (please bring \$10 - \$15 with you for rental and transportation) In case of rain Walker Art Museum.
Social outing leader - Olaf Hall-Holt
Calhoun or Walker Art Museum SW6.14-7.16.10

Friday, July 16

10:00am-12:00pmFinal presentationsLind Hall 409 SW6.14-7.16.10
12:00pm-1:00pmPoster session and pizzaLind Hall 400 SW6.14-7.16.10
Abstracts
Silas Alben (Georgia Institute of Technology) Swimming and flapping in vortex wakes
Abstract: Keywords: fish swimming, vortices, krill, fins Abstract: We consider two problems related to the propulsion of flexible surfaces in vortex wakes. First, we present a simple model of a trout swimming in a cylinder wake, which saves energy by slaloming through a vortex street. We find analytic solutions and compare with previous experiments and numerics. Second, we study ``inverted drafting'' in flags, in which the drag force on one flag is increased by excitation from the wake of another. The types of drafting and dynamics (synchronization and erratic flapping) depend on the separation distance between the flags. We may also discuss recent work on krill swimming and an optimal design for fish fins.
Erhan Bayraktar (University of Michigan) Strict local martingale deflators and pricing American call-type options
Abstract: We solve the problem of pricing and optimal exercise of American call-type options in markets which do not necessarily admit an equivalent local martingale measure. This resolves an open question proposed by Fernholz and Karatzas [Stochastic Portfolio Theory: A Survey, Handbook of Numerical Analysis, 15:89-168, 2009].

Joint work with Kostas Kardaras and Hao Xing. Available at http://arxiv.org/abs/0908.1082.

Gordon Joseph Berman (Princeton University), Kenny Breuer (Brown University), Randy H. Ewoldt (University of Minnesota), Hermes Gadêlha (University of Oxford), Jifeng Hu (University of Minnesota), Pieter Jan Antoon Janssen (University of Wisconsin), Arshad Kudrolli (Clark University), Amy Lang (University of Alabama), Ronald G. Larson (University of Michigan), Enkeleida Lushi (New York University), Hassan Masoud (Georgia Institute of Technology), Hoa Nguyen (Tulane University), Clara O'Farrell (California Institute of Technology), Sarah Olson (Tulane University) Poster Sound Bites
Abstract: No Abstract
Gordon Joseph Berman (Princeton University) Reconstructing the behavior of terrestrial fruit flies
Abstract: The traditional paradigm for the lab-based study of animal behavior has been to place an organism in a restricted environment and to understand it through the lens of a discrete set of allowed behaviors. While these limitations allow for more focused questions and higher data throughput, the particularities of these restrictions almost inevitably have implications for the resulting output. Moreover, the choice of a discretized classification by which the experiment describes the animal’s movements is often fraught with arbitrariness and anthropomorphism -- as well as the fact that a discrete set of behaviors may not even exist in the first place. What we aim to do here is to apply a data-driven approach to parameterize the behavior of a genetic model species, the fruit fly Drosophila melanogaster. Borrowing techniques from computer vision, machine learning, nonlinear dynamics, and statistical physics, our goal is to film long sequences of the insects moving within a relatively unrestricted environment and to translate these sequences into time-series data. From these time-series, we hope to build a descriptive language for fly behavior that can provide insight into how these creatures move, groom, communicate, mate, and otherwise live their lives.
Steven Bleiler (Portland State University) Evaluating regulatory strategies for emmision abatement - An engineering approach
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Luca Brandt (Royal Institute of Technology (KTH)) Numerical simulations of a free squirmer in a viscoelastic fluid
Abstract: The locomotion of biological microorganisms has been the object of much research over the last half of a century. Although significant progress has been made in the study of motion in Newtonian fluids, many biological cells such as bacteria often encounter viscous environments with suspended microstructures or macromolecules. The physics of micro-propulsion in such a non-Newtonian viscoelastic fluid has only recently started to be addressed. In our work, we present a numerical study of the motility of an axisymmetric spherical squirmer in a polymeric flow. The microswimmer that we consider here is driven by a purely tangential distortion on the outer surface reproduced as non-homogenous boundary condition on a rigid sphere. We solve the hydrodynamic Stokes equation (zero Reynolds number) with the extra stress term generated by advection and stretching of polymers. As transport equation for the polymeric stress, we use here the nonlinear Giesekus model. The swimming speed is lower in a visco-elastic fluid and is asymptotically recovering for large Weissenberg numbers approaching values only about 15% smaller than in a Newtonian fluid. Interestingly, the efficiency is seen to significantly increase as the viscosity of the polymeric fluid is increased.
Kenny Breuer (Brown University) Synchronization of flagella and cilia through hydrodynamic interactions
Abstract: Many biological systems use flexible filaments moving in a viscous fluid to achieve motility or fluid transport. Examples include bacteria that use flagella to swim, paramecium that use cilia for motion and cilia on the wall of the lungs used for particulate removal. In tall of these cases, the filaments are observed to synchronize their motion, and since there is no chemical or physiological coordination, this synchronization is thought to be mediated by hydrodynamic forces. We demonstrate the use of a model system that captures all of the essential features in hydrodynamic synchronization, including multiple filaments interacting through viscous stresses, as well as the presence of structural flexibility in each filament, which is known to be a necessary component for synchronization. We explore the dynamics of hydrodynamic synchronization in this modelsystem using experiments, numerical simluations that employ regularized Stokeslets, and a simple analtyical model. All three approaches give consistent results and point to the relative roles of viscous stresses, structural flexibility in the synchronization dynamics.
Guillaume Carlier (Université de Paris-Dauphine) Monge-Kantorovich optimal transport problem
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Guillaume Carlier (Université de Paris-Dauphine) Strictly convex transportation costs
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Guillaume Carlier (Université de Paris-Dauphine) The case cost=distance
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Guillaume Carlier (Université de Paris-Dauphine) Economic applications of optimal transport
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Guillaume Carlier (Université de Paris-Dauphine) Congested transport
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Rene Carmona (Princeton University) Energy and emissions markets, and the existing cap-and-trade schemes
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Rene Carmona (Princeton University) Discrete time competitive equilibrium models for cap-and-trade schemes and the carbon tax
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Rene Carmona (Princeton University), Max Fehr (London School of Economics and Political Science) Implementation of a simple model: first example
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Rene Carmona (Princeton University) Mathematical models for allocation mechanisms and cost distribution
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Rene Carmona (Princeton University), Max Fehr (London School of Economics and Political Science) Implementation of a simple model: second example
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Rene Carmona (Princeton University) Discrete time competitive equilibrium models for cap-and-trade schemes and the clean development mechanism
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Rene Carmona (Princeton University) Stochastic optimization and first continuous time models of cap-and-trade schemes
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Rene Carmona (Princeton University) Binary martingales and option pricing: 1) Reduced form models; 2) Perturbation methods
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Rene Carmona (Princeton University) Singular BSDEs appearing in cap-and-trade models
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Rene Carmona (Princeton University) Game theory, Nash equilibrium, and electricity prices with strategic market players
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Rene Carmona (Princeton University) Stochastic games: Pontryagin maximum principle and the Isaacs conditions
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Rene Carmona (Princeton University) Examples of linear-quadratic stochastic games in environmental finance
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Stephen Childress (New York University) Tutorial: Introduction to locomotion at low and intermediate Reynolds numbers
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Howie Choset (Carnegie Mellon University) Optimal coordinate choice for locomoting systems
Abstract: Work with Ross Hatton. Keywords: locomotion, snake robots, gait design Abstract: Animals often use gaits — cyclic changes in shape producing a net displacement — to move through their environments. In robotics, we are interested in planning motions for artificial systems that can match or exceed the locomotive capabilities of animals. A fundamental question of locomotion is "What are the characteristics of a useful gait?" The geometric mechanics community has made significant progress in answering this question, identifying functions of the system shape that capture the net displacements induced by broad classes of gaits without having to individually test each possible motion. In this talk, we first introduce these results with the aim of separating them from the specialized language of differential geometry and making them accessible to a broader audience. Following this introduction, we then examine how the choice of generalized coordinates quality of the locomotion functions, a question which has not previously been addressed.
Luis H. Cisneros (University of Arizona) From individual to collective swimming dynamics of bacillus subtilis
Abstract: Joint work with John O. Kessler (Physics Department, University of Arizona, Tucson, AZ 85721). Keywords: bacteria, interacting self propelled particles, collective behavior, PIV, bio-fluid-dynamics Abstract: Spatial order and fast collective coherent dynamics of populations of swimming bacteria emerges from local interactions and from flows generated by the organisms’ locomotion. The transition from dilute, to intermediate, to high concentrations of cells will be demonstrated by movie clips. Analyses of these data, presented as probability density functions for swimming velocity, show that the low concentration phase which exhibits swimming speeds characteristic of individual bacteria, arrives at the anomalously high speed phase, ZBN, the ZoomingBioNematic, via an intermediate phase that exhibits surprisingly low mean speeds. The origin of this phenomenon relates to scattering and the known dynamics of velocity flipping. Particle Imaging Velocimetry (PIV) was used for analysis of mixing, and of collective velocities, correlated with alignment within coherent patches. Supported by the Department of Energy, grant DOE-W-31-109-ENG-38.
Aline J. Cotel (University of Michigan), Paul W. Webb (University of Michigan) Living in a turbulent world: Interactions between fishes and eddies
Abstract: Keywords: fish/eddy interaction, vorticity, evolution of control surfaces and function, turbulence, fish responses. Abstract: The natural habitats of fishes are characterized by water movements driven by a multitude of physical processes of either natural or human origin. The resultant unsteadiness is exacerbated when flow interacts with surfaces, such as the bottom and banks, and protruding objects, such as corals, boulders, and woody debris. There is growing interest in the impacts on performance and behavior of fishes swimming in "turbulent flows." The ability of fishes to stabilize body postures and their swimming trajectories is thought to be important in determining species distributions and densities, and hence resultant assemblages in various habitats. Furthermore, water flow, structure and vorticity are related to the shape of the body and fins of fishes swimming largely in relatively steady flows. Adaptations to minimize energy losses would be anticipated. We suggest such mechanisms may be found in varying the length of the propulsive wave, stiffening propulsive surfaces, and shifting to use of the median and paired fins when swimming at low speeds. The archetypal streamlined "fish" shape reduces destabilizing forces for fishes swimming into eddies. Understanding impacts of turbulence and vorticity on fishes is important as human practices modify water movements, and as turbulence-generating structures ranging from hardening shorelines to control erosion, through designing fish deterrents, to the design of fish passageways become common.
Darren G. Crowdy (Imperial College London) Low-Reynolds-number swimming near walls and free surfaces
Abstract: There has been much recent interest in understanding the dynamics of low-Reynolds-number swimmers near no-slip boundaries and free capillary surfaces. This talk will present theoretical ideas for studying the dynamics of such swimmers within the framework of simple two dimensional models. The 2D models are developed using the methods of complex analysis and afford significant analytical advantages while still capturing the essential mechanisms of (certain) fully three dimensional situations. In many cases the approach yields explicit nonlinear dynamical systems that can be directly studied. The models can rationalize behaviour observed in numerical and laboratory experiments and can provide predictions for the swimmer dynamics in more complicated situations. We will survey results on swimming near a no-slip wall [joint work with Y. Or], swimming in other con ned geometries [joint work with O. Samson] and swimming near a free capillary surface [joint work with S. Lee, O. Samson, A. Hosoi and E. Lauga].
Zhenlu Cui (Fayetteville State University) A kinetic theory for suspensions of micoswimmers
Abstract: Using a nonlocal nematic potential, we present a kinetic theory for nonhomogeneous suspensions of micoswimmers. We then study the steady states to an imposed weak shear. Our results show that the activity parameter will result in permeative or oscillatory flow behaviors at the leading order depending the Leslie tumbling parameter. The linear viscoelasticity is also calculated, which is similar to chiral liquid crystals.
John O. Dabiri (California Institute of Technology) Using vortices for locomotion
Abstract: Keywords: vortices, locomotion, swimming, flying Abstract: The formation and shedding of fluid vortices is an inevitable consequence of movement for all but the smallest of swimming and flying organisms. Can animals use these vortices to enhance locomotion? If so, can their methods of vortex-enhanced propulsion be translated to engineered systems? This talk will describe experimental studies of jellyfish and numerical simulations of eels that suggest candidate mechanisms to enhance the efficiency and speed of locomotion by using vortices. A bio-inspired underwater vehicle is created to test the ideas in an engineering context. It appears that swimming and flying animals have significant opportunities to optimize their locomotion by making use of vortices.
Mark Denny (Stanford University) Subtleties in nature’s simplest form of locomotion: jet propulsion in squids and scallops
Abstract: Keywords: squid, scallop, jet propulsion, hydrodynamic efficiency, Antarctica, ontogeny, scaling Abstract: Among multicellular animals, jet propulsion is nature’s simplest (and arguably its oldest) form of aquatic locomotion. Any flexible, hollow body girdled by circumferential muscle fibers, can, by expelling fluid through an orifice, produce thrust and thereby swim. Despite the fundamental simplicity of this locomotory mechanism, aspects of its realization in nature continue to provide insight into the physiology, ecology, and evolution of a wide variety of animals. In this talk, I report on two mollusks that use jet propulsion. The Antarctic scallop is one of only a few bivalves that can swim. Like its temperate and tropical cousins, it claps its shells together to expel a jet of water sufficiently powerful to lift both its internal organs and its dense calcium-carbonate shell off the seafloor. But the Antarctic scallop must perform this feat in water at -1.86 degrees C, a temperature at which muscle power is reduced and water’s viscosity is 1.43 times that of tropical water. Shell mass in the Antarctic scallop is much reduced relative to tropical scallops, but muscle mass is reduced even more. The only net advantage evident in Antarctic scallops is the increased resilience of the “spring” that opens the shell, suggesting that even slight increases in hydrodynamic efficiency can be selected during evolution. Increases in hydrodynamic efficiency may also play an important role in squid locomotion. Unlike most jet propulsors (e.g., jellyfish, salps, clams), squids can actively control the size of the orifice through which water is expelled. Appropriate narrowing of the jet orifice during mantle contraction can boost the efficiency of both the hydrodynamics of propulsion and the contraction of muscle. This potential increase in efficiency may be most important in small juvenile squid, for whom jet propulsion is otherwise very inefficient.
Ivar Ekeland (University of British Columbia) Non-constant discount rates, time inconsistency, and the golden rule
Abstract: In economic theory one typically discounts future benefits at a constant rate. An example of this is the celebrated model of endogeneous growth, originating with Ramsey (1928), which leads to the so-called golden rule in macroeconomics. There are now excellent reasons (intergenerational equity, for instance) to use non-constant discount rates. There is then a problem of time-inconsistency: a policy which is optimal today will no longer be so when the time comes to implement it. So optimization is pointless, and a substitute has to be found for optimal strategies. We will define such a substitute, namely equilibrium strategies, show how to characterize them, and investigate what happens to the golden rule. This is joint work with Ali Lazrak.
Ivar Ekeland (University of British Columbia) The Merton problem with hyperbolic discounting
Abstract: There is strong evidence that individuals discount future utilities at non-constant rates. The notion of optimality then disappears, because of time inconsistency (see the Tuesday colloquium) and rational behaviour then centers around equilibrium strategies. I will investigate portfolio management with hyperbolic discounting (the discount rate increases with time), and I will show that this may explain some well-known puzzles of portfolio management. This is joint work with Traian Pirvu.
Acmae El Yacoubi (Cornell University), Daniel Ivan Goldman (Georgia Institute of Technology), Zhi (George) Lin (University of Minnesota), Yizhar Or (Technion-Israel Institute of Technology), Neelesh A. Patankar (Northwestern University), Jifeng Peng (University of Alaska), Henry Shum (University of Oxford), Saverio Eric Spagnolie (University of California, San Diego), Wanda Strychalski (University of California, Davis), Susan S. Suarez (Cornell University), Daniel See-Wai Tam (Massachusetts Institute of Technology), Sheng Xu (Southern Methodist University), Jeannette Yen (Georgia Institute of Technology) Poster Sound Bites
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Acmae El Yacoubi (Cornell University) Computational study of the interaction of free moving particles at intermediate Reynolds numbers
Abstract: In this new implementation of the Immersed Interface Method, we solve for the coupled dynamics of free moving objects in a fluid. We test the code by comparing our results with experimental data on falling plates and cylinders. We further present the dynamics of an array of falling cylinders and contrast the results of the even and odd configuration.
Jeff D. Eldredge (University of California, Los Angeles) A unified framework for inviscid and viscous simulations of biolocomotion
Abstract: We present a formulation for coupled solutions of fluid and body dynamics in problems of biolocomotion. This formulation unifies the treatment at moderate to high Reynolds number with the corresponding inviscid problem. By a viscous splitting of the Navier–Stokes equations, inertial forces from the fluid are distinguished from the viscous forces, and the former are further decomposed into contributions from body motion in irrotational fluid and ambient fluid vorticity about an equivalent stationary body. In particular, the added mass of the fluid is combined with the intrinsic inertia of the body to allow for simulations of bodies of arbitrary mass, including massless or neutrally buoyant bodies. The resulting dynamical equations can potentially illuminate the role of vorticity in locomotion, and provide new pathways toward reduced-order modeling. Examples of articulated or continuously deforming bodies undergoing swimming or flying kinematics are presented and discussed.
Randy H. Ewoldt (University of Minnesota) Helicobacter pylori (stomach bacterium) moves through mucus by reducing mucin viscoelasticity
Abstract: The ulcer-causing gastric pathogen Helicobacter pylori is able to swim through the viscoelastic mucus gel that coats the stomach wall, but its mechanism of locomotion through an acidic gel environment is poorly understood. This experimental study indicates that the helicoidal-shaped H. pylori achieves motility by altering the rheological properties of its environment. H. pylori locally raises the pH of its environment in order to survive in the acidic conditions of the stomach. This local change of pH affects the rheology of the surrounding mucus material. We show that gastric mucus is pH dependent, changing from a gel at acidic conditions (low pH) into a viscous solution at more neutral conditions (higher pH). Microscopy studies of the motility of H. pylori in gastric mucin show that the bacteria swim freely at high pH, and are strongly constrained at low pH. Joint work with J. P. Celli, B. S. Turner, N. H. Afdahl, S. Keates, I. Ghiran, C. Kelly, G. H. McKinley, P. So, S. Erramilli, and R. Bansil. http://dx.doi.org/10.1073/pnas.0903438106
Lisa J. Fauci (Tulane University) Lamprey locomotion: An integrative muscle mechanics - fluid dynamics model
Abstract: In an effort towards an understanding of the generation and control of vertebrate locomotion, including the role of the CPG and its interactions with reflexive feedback, muscle mechanics, and external fluid dynamics, we study a simple vertebrate, the lamprey. Lamprey body undulations are a result of a wave of neural activation that passes from head to tail, causing a wave of muscle activation. These active forces are mediated by passive structural forces. We present a model that includes the complete fluid-structure interaction problem, in which the body is elastic and deforms according to both internal muscular forces and external fluid forces. The model uses an immersed-boundary framework for solving the Navier-Stokes equations of fluid motion, and includes a nonlinear muscle model, an elastic body, and an adaptive solver that is accurate at length and velocity scales that are appropriate for swimming lampreys. The effects of various body and environmental properties, including tapered and uniform body shapes, different body stiffness, varying muscle parameters, and a range of viscosities are examined as they relate to swimming dynamics and energy requirements. (This is joint work with Chia-yu Hsu, Eric Tytell, Thelma Williams, Tyler McMillen and Avis Cohen.)
Max Fehr (London School of Economics and Political Science) Simulations of realistic EU ETS models
joint work with U. Cetin & P. Barrieu (London School of Economics)
Abstract: We propose a model for risk neutral futures price dynamics in the European Unions Emissions Trading Scheme (EU ETS). Historical price dynamics suggests that both allowance prices for different compliance periods and CER prices for different compliance periods are significantly related. To obtain a realistic price dynamics we take into account the specific details of the EU ETS compliance regulations, such as banking and the link to the Clean Development Mechanism (CDM), and exploit arbitrage relationships between futures on EU allowances and Certified Emission Reductions.
Frank E. Fish (West Chester University) Winged aquatic locomotion for high energetic efficiency through vortex control
Abstract: Keywords: hydrodynamics, lift-based propulsion, leading edge tubercles, dolphin, whale, manta, vorticity control Abstract: Optimization of energy by large aquatic animals (e.g., dolphins, whales, manta) requires adaptations that control hydrodynamic flow to reduce drag, and improve thrust production and efficiency. Although streamlining of the body and appendages minimizes drag, highly derived aquatic animals utilize mechanisms of propulsion and control based on lift generation, which maximizes thrust production and minimizing drag. Oscillations of the wing-like fins and flukes, which are hydrofoils, generate thrust throughout the stroke cycle and maintain a propulsive efficiency over 80%. This high efficiency is dependent on spanwise and chordwise bending and management of swimming kinematics to control vorticity. Control of vorticity to improve locomotor performance for maneuverability is enhanced by modification to the leading edge of control surfaces. The humpback whale (Megaptera novaeangliae) flippers are unique because of the presence of large tubercles along the leading edge, which gives this surface a scalloped appearance. The tubercles function to produce vortical flows over the surface of the flipper and control lift characteristics at high angles of attack, where stall would occur. The potential benefits from mimicking these biological innovations as applied to engineered systems operating in fluids are high speeds, vorticity control, reduced detection, energy economy, and enhanced maneuverability.
Hermes Gadêlha (University of Oxford) Nonlinear instability in flagellar dynamics: a novel modulation mechanism in sperm migration?
Abstract: Throughout the natural world, cells and organisms use flagella and cilia to propel fluid, achieve cell motility and a range of other functions. The mechanism regulating their waveform, however, is a long-standing biological problem. Indeed, the emergence of such flagellar undulatory waves is a consequence of an intricate balance of fluid dynamic viscous forces, flagellar elastic resistance, and the active bending generated by internal motor proteins. By using theoretical modelling and numerical computations accounting for high curvatures observed physiologically, we show that flagellar compression due to viscous friction and the internal forces may initiates an effective buckling behaviour that leads to an asymmetric flagellar beating and, consequently, switching sperm swimming from a straight migratory trajectory to a circling path. These results demonstrate that observed asymmetric flagellar beating may arise due to a dynamic instability, and not necessarily require some intrinsic asymmetric in the beating mechanism. This behaviour may be important in understanding mammalian sperm trapping, potentially a crucial step in natural fertilisation.
Eamonn Andrew Gaffney (University of Oxford) Aspects of human sperm motility: Observation and theory
Abstract: Studying human spermotozoa motility is a subject of growing importance due to human male subfertility and the fact that the in-vitro fertilisation interventions that bypass normal sperm motility are invasive and entail significant risk for the healthy female partner, as well as being economically prohibitive for many. We present examples of how fluid and continuum dynamics can provide novel insights concerning the mechanics of human spermatozoon behaviour, focussing on the interpretation of recent high resolution imaging.
Daniel Ivan Goldman (Georgia Institute of Technology) Experiments and models reveal principles of locomotion of the sand-swimming sandfish lizard
Abstract: In this talk I will summarize our recent progress in experiments and models of the locomotion of a sand-swimming lizard, the sandfish ({em Scincus scincus}). We use high speed x-ray imaging to study how the 10 cm-long sandfish swims at 2 body-lengths/sec within sand, a granular material that displays solid and fluid-like behavior. Below the surface the lizard no longer uses limbs for propulsion but generates thrust to overcome drag by propagating an undulatory traveling wave down the body. While viscous hydrodynamics can predict swimming speed in fluids like water, an equivalent theory for granular drag is not available. To predict sandfish swimming speed, we develop an empirical resistive force model by measuring drag force on a small cylinder oriented at different angles relative to the displacement direction and summing these forces over the animal movement profile. The model correctly predicts the animal's wave efficiency (ratio of forward speed to wave speed) as approximately 0.5. The empirical model agrees with a more detailed (and more accurate) numerical simulation: a multi-segment model of the sandfish coupled to a multi-particle Molecular Dynamics simulation of the granular media. The agreement between models and the prediction of biological wave efficiency demonstrate that the non-inertial swimming occurs in a frictional fluid and the Molecular Dynamics simulation allows us to visualize the self-generated fluid surrounding the sandfish as it swims. We use the principles discovered to construct a sand-swimming physical model (a robot) which, like in our empirical and multi-particle numerical model, swims fastest using the preferred sandfish wave pattern.
Daniel Ivan Goldman (Georgia Institute of Technology) Sensitive dependence of the motion of a legged robot on sand
Abstract: Legged locomotion on flowing ground ({em e.g.}~granular media) is unlike locomotion on hard ground because feet experience both solid- and fluid-like forces during surface penetration. Recent bio-inspired legged robots display speed relative to body size on hard ground comparable to high performing organisms like cockroaches but suffer significant performance loss on flowing materials like sand. In laboratory experiments we study the performance (speed) of a small (2.3~kg) six-legged robot, SandBot, as it runs on a bed of granular media (1~mm poppy seeds). For an alternating tripod gait on the granular bed, standard gait control parameters achieve speeds at best two orders of magnitude smaller than the 2~body lengths/s ($approx 60$~cm/s) for motion on hard ground. However, empirical adjustment of these control parameters away from the hard ground settings, restores good performance, yielding top speeds of 30~cm/s. Robot speed depends sensitively on the packing fraction $phi$ and the limb frequency $omega$, and a dramatic transition from rotary walking to slow swimming occurs when $phi$ becomes small enough and/or $omega$ large enough. We propose a kinematic model of the rotary walking mode based on generic features of penetration and slip of a curved limb in granular media. The model captures the dependence of robot speed on limb frequency and the transition between walking and swimming modes but highlights the need for a deeper understanding of the physics of granular media. Journal paper: Li et al, PNAS, 2009.
Michael D. Graham (University of Wisconsin) Transport in suspensions of swimming organisms
Abstract: Experiments and simulations indicate that suspensions of swimming microorganisms can exhibit complex phenomena, including pattern-forming instabilities, large scale fluid motions and enhanced passive scalar transport. This talk is an overview of theoretical and computational work describing some of these phenomena. Emphasis will be placed on analysis of various correlation functions associated with the dynamics. The talk concludes with a brief presentation of new directions in this area, including the coordinated motion of collections of bacterial flagella. This is joint work with Patrick T. Underhill and Pieter J. A. Jansssen.
Andong He (Pennsylvania State University) Inertial corrections to Darcy’s law for Hele-Shaw flows
Abstract: A nonlinear unsteady Darcy's equation to include inertial effects of a Hele-Shaw flow and the conditions under which it reduces to the classical Darcy's law are discussed. In the absence of surface tension, we derive a generalized Polubarinova-Galin equation for flows in a circular Hele-Shaw cell using the method of conformal mapping. The linear stability of the base-flow state is examined by perturbing the conformal mapping in form of polynomial modes. We find that small inertia always has the tendency to stabilize the interface.
Christel Hohenegger (New York University) Stability of active suspensions
Abstract: Keywords: active suspensions, kinetic theory Abstract: One of the challenges in modeling the transport properties of complex fluids (e.g. many biofluids, polymer solutions, particle suspensions) is describing the interaction between the suspended micro-structure with the fluid itself. Here I will focus on understanding the dynamics of active suspensions, like swimming bacteria or artificial micro-swimmers. Using a recently derived kinetic model, I have investigated the linearized structure of such an active system near a state of uniformity and isotropy. I will show that system instability can arise only from the dynamics of the first azimuthal mode in swimmer orientation, that the growth of fluctuations for a suspension of anterior actuated swimmers is associated with a proliferation of oscillations in swimmer orientation, that diffusion acts as a smoothing parameter, and that at small-scales the system is controlled independently of the nature of the suspension. Finally a prediction about the onset of the instability as a function of the volume concentration of anterior actuated swimmers and a comparison with numerical simulations is made.
David Hu (Georgia Institute of Technology) The wet-dog shake
Abstract: Joint work with Andrew K. Dickerson, Zachary G. Mills, Paul C. Foster (School of Mechanical Engineering, Georgia Institute of Technology). While much attention has been devoted to the ability of animals to propel themselves through fluids, less work has been done on how they exploit fluids in their grooming habits. The problem of how animals clean and dry themselves involves complex flexible surfaces (hair, skin), unsteady speeds, and wetting/de-wetting of drops and fluid ligaments. In this experimental investigation, we investigate the ability of dogs, rats, mice and other hirsute mammals to rapidly oscillate their bodies in order to shed water droplets, nature's analogy to the spin cycle on a washing machine. High-speed videography and fur-particle tracking is employed to determine the angular position of the animal's shoulder skin as a function of time. We formulate the conditions for de-wetting and propulsion of water drops based on the balance of the forces of surface tension, centripetal forces (which tend to pull drops normally from the skin) and angular-acceleration forces (which tend to slide drops). We find that smaller animals shake fastest: specifically, shaking frequency scales as the shoulder radius to the -1/2 power, as is required for centripetal forces on drops to remain constant as animals grow. An important consideration in this process is the looseness of the skin with respect to the body, whose presence increases the peak speed and acceleration of their fur. The energy expenditure and remaining water moisture content of self-drying mammals is estimated.
Jifeng Hu (University of Minnesota), Qixuan Wang (University of Minnesota) Low Reynolds number swimming models of cell blebbing
Abstract: Plasma membrane blebs are dynamic cytoskeleton-regulated cell protrusions that have been implicated in apoptosis, cytokinesis, and cell movement. A variety of theoretical and experimental results support the hypothesis that nonapoptotic membrane blebbing plays a central role for cell migration and cancer cell invasion. For cancer cells crawling through a 3D matrix, there are two morphologically distinguished modes of invasion: one that appears as a mesenchymal cell movement that relies on proteolytic degradation of the surrounding matrix and another that adopts a rounded, more amoeboid mode of motility that frequently is accompanied by cell blebbing. Here we will focus on the latter mode--cell migration through a 3D matrix by cell blebbing. To date, because of the limitation of experimental systems, most mechanisms governing plasma membrane blebbing are derived from 2D standard cell cultures that display blebbing under certain conditions. For example, much has been done for blebbing cells crawling on a substrate by adhesion. When lifted to 3D environment, the mechanisms may be totally different, and in the absence of interaction between the cell and the extracellular matrix, we now come to the classic physical problem: swimming in low Reynolds number fluid. One possible propulsive mechanism in a low Reynolds number environment is cyclic deformation of the cell membrane. Two of the most important biological phenomena related to this cyclic cell shape deformation are the observed shape oscillations and cell blebbing. The former one may be well generalized to a single swimming sphere at low Reynolds number that exerts self-propulsion by means of small amplitude, high-frequency waves over the surface. However, for the cell blebbing problem, one sphere model may not be adequate. Instead, a minimal model may comprise several connecting spheres that can exchange mass among them. In the poster, we will first present a brief review of fundamental theories of swimming at low Reynolds number, together with some previous models. Next we will advance several of my models and discuss their properties.
Pieter Jan Antoon Janssen (University of Wisconsin) Flagellar bundling
Abstract: We numerically investigate the bundling between flagella. For this, we consider two flexible helices next to each other. Each helix is modeled as several prolate spheroids connected at the tips by springs. On the first spheroid, a constant torque is applied. Torsion springs at the connections provide bending and twisting resistance. Hydrodynamic interactions are incorporated via a modified non-singular Stokeslet. Additionally, there is a repulsive force and torque, based on the Gay-Berne potential to prevent crossing of the flagella. Our results provide some insights in the details of the bundling process. In the initial stage, rotlet interactions between the rotating helices ensures that both deflect each other. Due to the end point fixation, this deflection combined with the rotlet interaction leads to the flagella rotating around each other. Longer simulations show that the tips of a flagella pair only rotate about once around each other, in contrast with a more complicated entwinement suggested before. Flagella closer together bundle faster.
Sunghwan (Sunny) Jung (Virginia Polytechnic Institute and State University) Paramecium swimming near a wall
Abstract: Most micro-organisms often swim in a variety of complex environments as their natural habitat. For instance, Paramecium tend to congregate and swim near the boundaries. We investigate the locomotion of Paramecium in confined geometries while comparing its motion in the un-bounded fluid. A modified theoretical model based on Taylor’s sheet is developed to study the boundary effect on its motion. During experiments, we introduce Paramecium in capillary tubes of different sizes and measure the influence of the tube diameter on the swimming velocity. The data from the experiments is compared with the theoretical model to test its validity and understand the ciliary locomotion of organisms in a confined channel.
Eva Kanso (University of Southern California) Passive locomotion in unsteady flows
Abstract: The passive locomotion of a body placed in the flow of periodically-generated vortices is studied. This work is motivated by recent experimental evidence that live and dead trout exploit the vortices in the wake of an oscillating cylinder to swim upstream. We consider a simple model of a rigid body interacting dynamically with point vortices introduced periodically into the flow to emulate the shedding of vortices from an external source. We show the existence of periodic solutions where the body `swims' passively against the flow by extracting energy from the ambient vortices. We also find solutions where the body holds station in the incoming wake. However, for bodies of elongated geometries, rotational instabilities may hinder their motion. We propose active feedback control strategies to overcome these instabilities. (This is joint work with my graduate student Babak G. Oskouei)
Scott David Kelly (University of North Carolina - Charlotte) Idealized modeling of planar fishlike swimming for motion control
Abstract: Models for aquatic locomotion generally seek to balance fidelity and scope with analytical or computational tractability. When the goal in model development is a platform for model-based feedback control design, analytical structure is essential to provide a point of access for most current design techniques, but some fidelity may be sacrificed as long as the scope of the model encompasses the range of situations under which control will be applied. This talk will describe a model for simplified fishlike swimming based on the Hamiltonian equations governing the interaction of a free deformable body with a system of point vortices in a planar ideal fluid. The use of this model in designing motion-control strategies for a biologically inspired robotic vehicle will be discussed, with a particular focus on the realization of energy-efficient gaits for solitary swimming and energy-harvesting methods for controlled schooling.
Jeff Randall Knisley (East Tennessee State University) Learning by investigation: A context for integrating statistics, mathematics, and computation
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Jeff Randall Knisley (East Tennessee State University) The Integration of … modeling, statistics, computation and calculus at East Tennessee State University
Abstract: No Abstract
Mimi Koehl (University of California, Berkeley) Effects of ambient water flow on locomotion
Abstract: Keyword: waves, turbulence, walking, swimming, larvae, crabs Abstract: Turbulent ambient currents and waves in marine habitats impose forces on organisms. The locomotory performance of organisms swimming in the water column and moving across the substratum is affected by environmental fluid dynamic forces. Therefore, the functional significance of morphological features and kinematics of locomoting organisms can best be understood if studied under the range of flow conditions they experience in their natural habitats. Three examples will be discussed: 1) Many bottom-dwelling marine animals produce microscopic larvae that are dispersed to new sites by ambient water currents. How do these weakly-swimming larvae carried in wavy, turbulent water flow manage to land on the sea floor in suitable habitats? 2) Horseshoe "crabs", Limulus polyphemus, gather in the surf zone to mate. How can they crawl in the waves without being pushed in the wrong direction or overturned by the back-and-forth flow of the waves? 3) Shore crabs, Grapsus tenuicrustatus, also live on wave-swept shores, where they spend part of their time in air and part underwater. How do they run in air (where gravity predominates) versus underwater (where hydrodynamic forces are important), and what happens when a wave hits?
Arshad Kudrolli (Clark University) Collective diffusion of self-propelled rods
Abstract: We perform physical experiments with self-propelled rods which undergo directed random motion on a substrate motivated by collective behavior in various active living systems such as bacterial colonies and hoofed animal herds. In particular, we examine the persistent random motion of rods as a function of the area fraction ϕ and study the effect of steric interactions on their diffusion properties. Self-propelled rods of length l and width w are fabricated with a spherocylindrical head attached to a beaded chain tail, and show directed motion on a vibrated substrate. The mean square displacement on the substrate grows linearly with time t for ϕ<w/l, before displaying caging as ϕ is increased, and stops well below the close packing limit. Direction autocorrelations decay progressively slower with ϕ. We describe the observed decrease of SPR propagation speed c(ϕ) with a tube model [1]. Further, we discuss the observed collective behavior such as aggregation at the boundaries and swirling motion which arise because of physical interactions between individuals [2]. [1]: "Concentration Dependent Diffusion of Self-Propelled Rods," A. Kudrolli, Phys. Rev. Lett. 104, 088001 (2010). [2]: "Swarming and swirling in self-propelled granular rods," A. Kudrolli, G. Lumay, D. Volfson, and L. Tsimring, Phys. Rev. Lett. 100, 058001 (2008).
Amy Lang (University of Alabama) Experimental studies to reveal the boundary layer control mechanisms of shark skin
Abstract: Same abstract as the contributed talk.
Amy Lang (University of Alabama) Experimental studies to reveal the boundary layer control mechanisms of shark skin
Abstract: This experimental work is investigating a new and unique passive boundary-layer separation control methodology derived from shark skin, functioning at the micro-scale level. The skin and denticles (scales) of sharks represent over 400 million years of natural selection for swimming efficiency. Evolutionary adaptations in the morphological structure of the shark skin, to develop unique boundary layer control (BLC) mechanisms, stem from the ensuing decrease in drag, probable increase in fin performance (e.g. thrust production) and enhanced turning agility for fast-swimming sharks. Shark denticles have been documented to be capable of bristling. A bristled microgeometry mimicking shark skin results in the formation of a system of interlocking embedded cavity vortices. Three mechanisms have been hypothesized which lead to boundary layer control via deterrence of separation over the shark skin. The first mechanism is the formation of embedded micro-vortices that increase momentum in the very near-wall region due to the resulting partial slip condition. The second mechanism is that the preferential flow direction inherent in the surface geometry inhibits global flow reversal and leads to passive actuation via denticle bristling. The third mechanism involves turbulence augmentation, or an additional energizing of flow, in the near-wall region and cavities, leading to higher partial slip velocities. The study involves engineers, working together with biologists Dr. Phil Motta (University of South Florida) and Dr. Robert Hueter (Mote Marine Laboratory), to fully comprehend the morphological bristling mechanism of shark denticles. Initial results for scale angles and morphology on hammerhead and shortfin mako sharks along with flow measurements over shark skin models embedded in a turbulent boundary layer will be presented.
Ronald G. Larson (University of Michigan) Swimming dynamics of a run-and-tumble bacterium with helical flagella
Abstract: To study the hydrodynamics of swimming of multi-flagellated bacteria, such as Escherichia coli, we develop a simulation method using a bead-spring model to account for the hydrodynamic and the mechanical interactions between multiple flagella and the cell body, the reversal of the rotation of a flagellum in a tumble and associated polymorphic transformations of the flagellum. This simulation reproduces the experimentally observed behaviors of E. coli, namely, a three-dimensional random-walk trajectory in run-and-tumble motion and steady clockwise swimming near a wall. Here we show using a modeled cell that the polymorphic transformation of flagellum in a tumble facilitates the reorientation of the cell, and that the time-averaged flow field near a cell in a run has double-layered helical streamlines. Moreover, the instantaneous flow field, which is strongly time-dependent, is more than 10-fold larger in magnitude than the time-averaged flow, large enough to affect the migration behavior of surrounding chemoattractants, with the Péclet number for these molecules being larger than one near a swimming cell.
Eric Lauga (University of California, San Diego) Symmetry-breaking in small-scale locomotion: Synchronization and efficiency optimization
Abstract: Keywords: Low Reynolds number; locomotion; symmetry-breaking; synchronization; cilia; optimization Abstract: Fluid mechanics plays a crucial role in many cellular processes. One example is the external fluid mechanics of motile cells such as bacteria, spermatozoa, algae, and essentially half of the microorganisms on earth. The most commonly-studied organisms exploit the bending or rotation of a small number of flagella (short whip-like organelles, length scale from a few to tens of microns) to create fluid-based propulsion. As a difference, Ciliated microorganisms swim by exploiting the coordinated surface beating of many cilia (which are short flagella) distributed along their surface. In this talk, we consider two instances of symmetry-breaking arising in small-scale locomotion. First, we address the observed flagellar synchronization between eukaryotic cells swimming in close proximity. By using a two-dimensional model, we show analytically and computationally that synchronization between co-swimming cells can be driven by hydrodynamic interactions alone if there is a geometrical symmetry-breaking displayed by the their flagellar waveforms. In a second part, we pose the problem of ciliary propulsion as an optimization problem. Specifically, for a spherical body, we compute numerically and theoretically the time-periodic tangential deformations of the body surface which leads to swimming of the body with optimal hydrodynamic efficiency. We show that this calculation leads to symmetry-breaking in the surface actuation, and the emergence of waves, reminiscent of the metachronal waves displayed by real biological cilia.
David Lentink (Wageningen University and Research Center) Leading-edge vortices elevate lift of autorotating plant seeds
Abstract: Joint work with W. B. Dickson2, J. L. van Leeuwen1, and M. H. Dickinson2. As they descend, the autorotating seeds of maples and some other trees generate unexpectedly high lift, but how they attain this elevated performance is unknown. To elucidate the mechanisms responsible, we measured the three-dimensional flow around dynamically scaled models of maple and hornbeam seeds. Our results indicate that these seeds attain high lift by generating a stable leading-edge vortex (LEV) as they descend. The compact LEV, which we verified on real specimens, allows maple seeds to remain in the air more effectively than do a variety of nonautorotating seeds. LEVs also explain the high lift generated by hovering insects, bats, and possibly birds, suggesting that the use of LEVs represents a convergent aerodynamic solution in the evolution of flight performance in both animals and plants. 1 Experimental Zoology Group, Wageningen University, 6709 PG Wageningen, Netherlands. 2 Bioengineering and Biology, California Institute of Technology, Pasadena, CA 91125, USA. Science 12 June 2009:
Vol. 324. no. 5933, pp. 1438 - 1440
DOI: 10.1126/science.1174196
http://www.sciencemag.org/cgi/content/abstract/324/5933/1438
Zhi (George) Lin (University of Minnesota) A hydrodynamic model of biogenic mixing
Abstract: We consider the stirring of an inviscid or Stoksian fluid caused by the locomotion of bodies through it. The swimmers are approximated by non-interacting cylinders or spheres moving steadily along straight lines. We find the displacement of fluid particles caused by the nearby passage of a swimmer as a function of an impact parameter. We use this to compute the effective diffusion coefficient from the random walk of a fluid particle under the influence of a distribution of swimming bodies. We find good agreement between theoretical results with simulations and identifies regions of dominant contribution to mixing. Also It is shown that Stokesian squirmers yields a great boost in effective diffusivity. Joint work with Jean-Luc Thiffeault and Stephen Childress.
Michael Ludkovski (University of California, Santa Barbara) Optimal switching problems and applications in energy finance
Abstract: Optimal Switching models are concerned with sequential decision making where the controller has a finite number of policy regimes. Such models arise naturally in pricing of energy assets, including tolling agreements for electricity production, natural gas storage facilities, carbon emission permits, etc. I will discuss the general mathematical structure of optimal switching models, including their relation to multiple stopping problems. I will then describe some work in progress with R. Sircar on exploration control in exhaustible resource management. In the second part of the talk, I will focus on numerical methods and implementation issues for optimal switching, especially simulation tools that extend Monte Carlo methods for American options.
Enkeleida Lushi (New York University) The turning-particle chemotaxis model in suspensions of micro-swimmers
Abstract: Suspensions of micro-swimmers display complex dynamics in response to chemical substances. They preferentially move and orient toward gradients of such a chemo-attractant in a process called chemotaxis. We present a new chemotaxis model based on the kinetic theory of swimmer suspensions in low Reynolds number fluid that is coupled to the chemo-attractant dynamics. The chemotactic response is included as a phenomenon due to fluxes in the individual swimmer. Entropy and linear stability analysis indicates a chemotaxis-induced instability at finite wavelengths for pusher and puller bacteria alike and regardless of their shape ratio. Nonlinear dynamics are investigated using numerical simulations of the full system in two dimensions. We observe aggregation in suspensions of pullers and mixing in suspensions of pushers.
Hassan Masoud (Georgia Institute of Technology) Low Reynolds number aerodynamics of flexible flapping wings at resonance
Abstract: Using three-dimensional computer simulations, we examine hovering aerodynamics of flexible planar wings oscillating at resonance. We model flexible wings as tilted elastic plates whose sinusoidal plunging motion is imposed at the plate root. Our simulations reveal that large-amplitude, resonance oscillations of elastic wings drastically enhance aerodynamic lift and efficiency of low-Reynolds-number plunging. Driven by a simple sinusoidal stroke, flexible wings at resonance generate a hovering force comparable to that of small insects that employ a very efficient, but much more complicated stroke kinematics. Our results indicate the feasibility of using flexible wings driven by a simple harmonic stroke for designing efficient microscale flying machines.
Laura Ann Miller (University of North Carolina) Tradeoffs between swimming and feeding: The curious case of the upside down jellyfish
Abstract: When studying the mechanics of swimming and flying, engineers and scientists often pose questions in the form of optimization strategies. This approach has been quite useful when trying to understand the kinematics of insect flight or the frequency that fish beat their tails. Understanding the kinematics and the morphology of animals that multitask is not as straightforward. For example, the elaborate tails of male guppy fish are likely not optimized for swimming efficiency or speed, but they do increase the likelihood of attracting a mate. In this presentation, the fluid dynamics of the currents generated by the upside down jellyfish *Cassiopea sp. *will be presented in the context of swimming and feeding. Medusae of this genus are unusual in that they typically rest upside down on the ocean floor and pulse their bells to generate feeding currents, only swimming when significantly disturbed. The pulsing kinematics and fluid flow around these upside-down jellyfish is investigated using a combination of videography, digital particle image velocimetry, and numerical simulation. There is no evidence of the formation of a train of vortex rings as observed in oblate medusae exhibiting rowing propulsion. Instead, significant mixing occurs around and directly above the oral arms and secondary mouths. Numerical simulations using the immersed boundary method agree with experimental measurements and suggest that the presence of porous oral arms induce net horizontal flow towards the bell and the absence of coherent vortex structures. The implications of these results on feeding and swimming efficiency will be discussed.
Richard D. Neidinger (Davidson College) Automatic differentiation using MATLAB OOP
Abstract: No Abstract
Hoa Nguyen (Tulane University) Fluid dynamics of phytoplankton with spines in linear shear flow
Abstract: Spines and other thin projections from cell surfaces literally expand the volume of fluid with which a cell interacts and may provide effective levers on which the flow can act. We use an immersed boundary formulation to solve the coupled phytoplankton-fluid system to predict the 3D trajectories of the cells within a background flow. We examine the effect of spines on the period of rotation of phytoplankton in linear shear flow.
Clara O'Farrell (California Institute of Technology) Lagrangian coherent structures in the wake on an anguilliform swimmer
Abstract: Joint work with John O. Dabiri. We study the dynamics and stability of the vortex wakes of swimming fish, with the aim of quantifying the role of vortex dynamics in determining the performance and limitations of fish-like swimmers (cf the work on vortex rings and their relation to the performance of jetting swimmers by Gharib et al 1998, Krueger and Gharib 2003, Linden and Turner 2004, Dabiri et al 2010). In order to enable studies of the dynamics and stability of these vortex flows, we analyze wake kinematics using Lagrangian coherent structures (LCS) (Haller 2000, 2001). We computed FTLE field in both two and three dimensions to extract the 2D and 3D LCS in the wake of a numerically-simulated, self-propelled anguilliform swimmer (Kern and Koumoutsakos 2006). The attracting and repelling LCS in the flow were found to clearly bound the vortices shed by the swimmer (Green et al 2010, Shadden et al 2006), and the shedding of two vortex ring per cycle and formation of a double row of vortex rings in the wake was observed. Fluid transport in the wake was studied using passive drifters seeded into the flow, and we observed the formation of slender lobes along the length of the swimmer, which "pull" fluid into the wake such that fluid particles inside each of these lobes are entrained into separate vortices in the swimmer's wake. Changes in the LCS in a flow are known to correspond to changes in the structure and dynamics of the underlying vortices (Green et al 2010, O'Farrell and Dabiri 2010), thus future work will focus on analysis of changes in LCS structure as indicators of changes in the dynamics and stability of the underlying vortex flow. References:
1) M. Gharib. E. Rambod, and K. Shariff. A universal time scale for vortex ring formation. J. Fluid Mech., 360:121-140, 1998.
2) P. S. Krueger and M. Gharib. The significance of vortex ring formation to the impulse and thrust of a starting jet. Phys. Fluids. 15:1271-81, 2003.
3) P. F. Linden and J. S. Turner. 'Optimal' vortex rings and aquatic propulsion mechanisms. Proc. R. Soc. B, 271:647-53, 2004.
4) J. O. Dabiri, S. P. Colin, K. Katija, and J. H. Costello. A wake-based correlate of swimming performance and foraging behavior in seven co-occurring jelly fish species. J. Exp. Biol., 13 (8): 1217-25, 2010.
5) G. Haller. Finding finite-time invariant manifolds in two-dimensional velocity fields. Chaos, 10:99, 2000.
6) G. Haller. Distinguished material surfaces and coherent structures in three-dimensional flows. Physica D, 149:1851–61, 2001.
7) S. Kern and P. Komoutsakos. Simulations of optimized anguilliform swimming. J. Exp. Biol., 209:4841–57, 2006.
8) M. A Green, C. W. Rowley, and A. J. Smits. Using hyperbolic Lagrangian Coherent Structures to investigate vortices in bio-inspired fluid flows. Chaos, 20:017509, 2010.
9) S. .C. Shadden, J. O. Dabiri, and J. E. Marsden. Lagrangian analysis of fluid transport in empirical vortex ring flows. Phys. Fluids., 18:047105, 2006.
10) C. O’Farrell and J. O. Dabiri. A Lagrangian approach to identifying vortex pinch-off. Chaos, 20:017513, 2010.
Sarah Olson (Tulane University) An integrative model of sperm motility
Abstract: Calcium (Ca2+) dynamics in mammalian sperm are directly linked to motility. These dynamics depend on diffusion, nonlinear fluxes, Ca2+ channels specific to the sperm flagellum, and other signaling molecules. The goal of this work is to couple Ca2+ dynamics to a mechanical model of a motile sperm within a viscous, incompressible fluid. We will present recent progress on elements of this integrative model.
Yizhar Or (Technion-Israel Institute of Technology) Dynamic and stability of low-Reynolds-number swimming near a wall
Abstract: The dynamics of a simple micro-swimmer model near a no-slip wall is formulated and analyzed. The model consists of an assemblage of spheres where propulsion is generated by rotation of the spheres. The geometric structure of the dynamics is analyzed, and stability properties of translation parallel to the wall are derived. The results are demonstrated through simulations and motion experiments on a macro-scale robotic swimmer in viscous fluid. I will also present results of a recent joint work with Darren Crowdy on utilizing complex analysis to formulate an explicit two-dimensional dynamic model of a treadmilling swimmer near a wall, and discuss ongoing work on extension to shape-changing controlled swimmers such as Purcell’s three-link swimmer model near a wall.
Neelesh A. Patankar (Northwestern University) The balance between drag and thrust in undulatory propulsion and implications on balistiform and gymnotiform locomotion
Abstract: The underlying basis of how swimming organisms propel themselves forward against resistance from the surrounding fluid has been studied for almost a century. Many traditional analyses have centered on decomposing the total force on a swimming body into drag and thrust. The validity of this decomposition has been controversial since it is not expected to hold for finite Reynolds number swimming. Yet, we report an approximate drag-thrust decomposition for one class of undulatory propulsors - the ribbon fins of gymnotiform and balistiform swimmers. The conclusion is based on high-resolution numerical simulations to calculate the force acting on an undulatory ribbon fin of the black ghost knifefish (Apteronotus albifrons). We show that drag-thrust decomposition is possible because there is very little spatial overlap between the drag-associated flow field and the thrust-associated flow field. This decomposition is different from the decomposition due to Lighthill that has been widely discussed in literature over the past four decades. The results above are used to interrogate balistiform and gymnotiform swimmers that move by undulating elongated ribbon fins attached to a body that is held nearly rigid. The question of whether this evolutionary adaptation may have a hydrodynamic basis was considered by Lighthill and Blake. They proposed, based on Lighthill's elongated body theory, that the ability of the ribbon fin to generate thrust is enhanced by the presence of a rigid body. This mechanism, commonly referred to as “momentum enhancement”, has been widely discussed in literature over the past two decades. Our results show that there is no momentum enhancement. This is explained by noting that the dominant mechanism of thrust generation by ribbon fins is different from that assumed in the theoretical approach of Lighthill. Nevertheless, many features of the morphology of gymnotiform and balistiform swimmers do appear to have a hydrodynamic basis. Specifically, it is found that the observed height of the ribbon fin, for a given body size, is such that the mechanical energy spent per unit distance, i.e., the mechanical cost of transport (COT) is optimized. Many open issues remain. First, it remains to be explored whether the drag-thrust decomposition can be extended to anguilliform and carangiform swimming. Second, while we have found optimal fin height for gymnotiform and balistiform swimmers for a given body size, it is still unclear whether keeping part of the body rigid is hydrodynamically better compared to a mode of swimming where the entire body is undulated (like in anguilliform swimming). Preliminary results interrogating these aspects will be discussed.
Neelesh A. Patankar (Northwestern University) Drag-thrust decomposition and optimality in swimming
Abstract: A novel constraint-based formulation to simulate self-propulsion has been developed. The numerical approach is used to obtain the following results. A drag-thrust decomposition is found in the propulsion by undulatory ribbon fins of gymnotiform and balistiform swimmers. The height of the ribbon fin of a gymnotiform swimmer seems optimized with respect to the mechanical Cost of Transport (COT). This can be explained based on the drag-thrust decomposition. Optimization based on COT is also found to work in case of pectoral fin movements of larval zebrafish.
Neelesh A. Patankar (Northwestern University) How does muscle forcing lead to translational motion during undulatory swimming?
Abstract: A set of linearized equations of motion, using a spring-link model, is derived for undulatory swimming. The transverse translational and rotational equations of motion give natural deformation modes of the body which feeds energy to the axial translational motion. It is found, consistent with prior work, that anisotropy in drag is required to enable swimming. The first three deformation modes are excited the most and consequently contribute most to the forward swimming velocity. Typical imposed frequencies, for the case of eel considered here, are found to be lower than the lowest natural frequency of the deformation modes of the body. Thus, lower modes are found to be more easily triggered by the muscle forcing.
Jifeng Peng (University of Alaska) A vortex sheet model of jellyfish swimming
Abstract: Jellyfish represents a group of animals that have an axisymmetric body and swim by periodically contracting the body and generating axisymmetric jets and vortices. In this study, jellyfish is modeled as an axisymmetric swimmer with a thin, flexible body. The wake vortex generated by the swimmer is approximated by a circular vortex sheet. Using this approach, the fluid dynamics and characteristics of the fluid wake are investigated. Swimming performance is also evaluated to quantify the effects of body shape and swimming modes. The study provides insights on fluid dynamical basis of jellyfish swimming and how certain body kinematics of jellyfish enhance the swimming performance.
Leif Gibbens Ristroph (Cornell University) How flying insects keep stable, up-right, and on-course
Abstract: For animals and machines alike, maintaining balance during flight is a crucial and demanding task. The need for airplane flight stability led to a schism between aviators who sought built-in, or passive, stability and those who emphasized the need for active controls. How has this tension played out for the first flyers, the insects? Our group combines table-top experiments on fruit flies and lap-top physically-based simulations to study insect flight stability and control. First, we show how directly perturbing the flight of insects unlocks the physics of flapping-wing flight and also reveals some remarkable properties of these critters’ sensory-neural systems. Second, we argue that these sophisticated fight control systems are largely sculpted by the physical requirement of stability. This idea leads to a general theory that links the body plans of insects with the controllers that must suppress the growth of instabilities, and we apply this theory to a variety of modern insects, flapping-wing robots, and even the prehistoric insects that were the first to take to the air.
Leif Gibbens Ristroph (Cornell University) Fruit flies modulate passive wing pitching to generate in-flight turns
Abstract: Flying insects execute aerial maneuvers through subtle manipulations of their wing motions. Here, we measure the free-flight kinematics of fruit flies and determine how they modulate their wing pitching to induce sharp turns. By analyzing the torques these insects exert to pitch their wings, we infer that the wing hinge acts as a torsional spring that passively resists the wing’s tendency to flip in response to aerodynamic and inertial forces. To turn, the insects asymmetrically change the spring rest angles to generate asymmetric rowing motions of their wings. Thus, insects can generate these maneuvers using only a slight active actuation that biases their wing motion.
David Saintillan (University of Illinois at Urbana-Champaign) Emergence of coherent structures and large-scale flows in biologically active suspensions
Abstract: Active particle suspensions, of which a bath of swimming bacteria is a paradigmatic example, are characterized by complex dynamics involving strong fluctuations and large-scale correlated motions. These motions, which result from the many-body interactions between particles, are biologically relevant as they impact mean particle transport, mixing and diffusion, with possible consequences for nutrient uptake and the spreading of bacterial infections. To analyze these effects, a kinetic theory is presented and applied to elucidate the dynamics and pattern formation arising from mean-field interactions. Based on this model, the stability of both aligned and isotropic suspensions is investigated. In aligned suspensions, an instability is shown to always occur at finite wavelengths, in agreement with previous predictions and simulations. In isotropic suspensions, a new instability for the active particle stress is also found to exist, in which shear stresses are eigenmodes and grow exponentially at low wavenumbers, resulting in large-scale fluctuations in suspensions of pusher particles above a threshold concentration. Numerical simulations of the kinetic equations are also performed, and applied to study the long-time nonlinear dynamics, which are characterized by transient particles clusters that form and break up in time, as well as complex chaotic flows correlated on the system size. The predictions from the kinetic model are then tested using direct particle simulations accounting for multi-body hydrodynamic interactions between model microswimmers: these simulations confirm the existence of a transition to correlated motions and large-scale flows above a certain volume fraction, as demonstrated by a sharp increase in density fluctuations, velocity correlation lengths, and mean particle velocities. The effect of this transition on fluid mixing is also investigated, and the emergence of large-scale flows is shown to significantly enhance convective mixing. To conclude, consequences of particle activity on the effective rheology of the suspensions are briefly discussed. We demonstrate that the rheology is characterized by much stronger normal stress differences than in passive suspensions, and that tail-actuated swimmers result in a strong decrease in the effective shear viscosity of the fluid.
David Saintillan (University of Illinois at Urbana-Champaign) Instability regimes in flowing suspensions of swimming micro-organisms
Abstract: Joint work with Amir Alizadeh Pahlavan. The effects of an external shear flow on the dynamics and pattern formation in a dilute suspension of swimming micro-organisms are investigated using a linear stability analysis and three-dimensional numerical simulations, based on the kinetic model previously developed by Saintillan and Shelley [``Instabilities, pattern formation, and mixing in active suspensions,'' Phys.~Fluids textbf{20}, 123304 (2008)]. The external shear flow is found to damp the instabilities that occur in these suspensions by controlling the orientation of the particles. We demonstrate that the rate of damping is direction-dependent: it is fastest in the flow direction, but slowest the direction perpendicular to the shear plane. As a result, transitions from three- to two- to one-dimensional instabilities are observed to occur as shear rate increases, and above a certain shear rate the instabilities altogether disappear. The density patterns and flow structures that arise at long times in the suspensions are also analyzed from the numerical simulations using standard techniques from the literature on turbulent flows. The imposed shear flow is found to have an effect on both density patterns and flow structures, which typically align with the extensional axis of the external flow. The disturbance flows in the simulations are shown to exhibit similarities with turbulent flows. However, the flows described herein are also significantly different owing to the strong predominance of large scales, as exemplified by the very rapid decay of the kinetic energy spectrum, an effect further enhanced after the transitions to two- and one-dimensional instabilities.
William W. Schultz (University of Michigan) Tutorial: Introduction to fish locomotion
Abstract: No Abstract
Michael J. Shelley (New York University) Snakes crawling and worms pushing on surfaces
Abstract: Many creatures navigate their world through undulation – the unidirectional propagation of bending waves along the body. Undulatory locomotion in a fluid is well studied, at least at low Reynolds number. There, undulation breaks time-reversal symmetry and an organism can locomote by using the anisotropy of fluid drag with respect to body shape. On land, limbless creatures such as snakes also use undulation to traverse "featureless" surfaces with relative ease. I will discuss theoretical models and experimental observations that illustrate how snakes accomplish this by using the frictional anisotropy provided their scales, as well as selective body lifting. To provide another example of an undulator in action, I will discuss some recent modeling and experiments that show how swimming nematodes interact with microfluidic environments filled with immovable obstacles.
Jian Sheng (University of Minnesota) Shear induced three-dimensional swimming characteristics of Dunaliella Primolecta in a microfluidic channel
Abstract: Joint work with Ahammed Anwar Chengala. The effects of flow shear on the swimming behavior of halophilic microalga Dunaliella primolecta is examined by an in-house developed digital holographic microscopy and microfluidic channel. To investigate the shear-induced response, the algal culture is injected into a channel with a cross section of 3.5 x 0.4 mm at several fluid flow rates, generating shear rates that are consistent with the energy dissipation levels in estuaries, coastal waters, and lakes. We quantified the kinematics of D. primolecta by the estimates of 3D swimming velocities, auto-correlation swimming velocities, kinetic spectral densities and swimming-induced dispersion. Preliminary analysis indicate that swimming velocities and dispersion were strongly mediated by local fluid shear rates. On-going analysis is aimed to reveal scaling parameters and functional relationships among small-scale fluid motion and microorganism motility characteristics.
Jian Sheng (University of Minnesota) Hydrodynamic surface interactions of Escherichia coli at high concentration
Abstract: Joint work with Harsh Agarwal. There is growing interest in understanding microscale biophysical processes such as the kinematics and dynamics of swimming microorganisms, and their interactions with surrounding fluids. Statistically robust experimental observations on swimming characteristics of bacteria in a wall bounded shear flow are crucial for understanding cell attachment and detachment during the initial formation of a biofilm. In this paper, we integrate microfluidics and holography to measure 3-D trajectories of a model bacteria, Escherichia coli (AW405), subjecting to a carefully controlled shear flow. Experiments are conducted in a straight mchannel of 40x3x0.2 mm with shear rates up to 200 (1/s). Holographic microscopic movies recorded at 40X magnification and 15 fps are streamed real-time to a data acquisition computer for an extended period of time (>5 min) that allows us to examine long term responses of bacteria in the presence of flow shear. Three-dimensional locations and orientations of bacteria are extracted with a resolution of 0.185 μm in lateral directions and 0.5 μm in the wall normal direction. The 3-D trajectories are tracked by an in-house developed particle tracking algorithm. Over three thousand of 3D trajectories over a sample volume of 380×380×200 μm have been obtained for our control (quiescent flow). Swimming characteristics, i.e. swimming velocities, Lagrangian spectra, dispersion coefficients, is extracted to quantify the cell-flow and cell-wall interactions. Preliminary results have revealed that near wall hydrodynamic interactions, i.e. swimming in circles and reducing lateral migration, cause the reduction in wall-normal dispersion, subsequently are responsible for wall trapping and prompting attachment. On-going analysis is to understand the effects of shear flow on such a mechanism.
Henry Shum (University of Oxford) A boundary element approach to bacteria approaching boundaries
Abstract: Interest is growing rapidly in understanding the swimming behaviour of micro-organisms near solid surfaces. This is an important aspect of biofilm initiation and has significant implications for the shipping, water and medical industries. Through boundary element methods, we can accurately simulate hydrodynamic interactions between a single bacterium and solid surfaces even when the separation distance is small. Past experiments and analytical arguments have shown that bacteria propelled by a flagellum tend to follow curved trajectories rather than straight when swimming near a surface. Our simulations verify this and we find that there can also be a stable separation from the wall, leading to circular orbits. We show that parameters controlling the shape of the swimmer can significantly influence this equilibrium distance. Hence, this model suggests that certain "designs" of bacteria accumulate at boundaries while others do not.
Ronnie Sircar (Princeton University) Dynamic oligopolies and differential games. I
Abstract: We discuss Cournot and Bertrand models of oligopolies, first in the context of static games and then in dynamic models. The static games, involving firms with different costs, lead to questions of how many competitors actively participate in a Nash equilibrium and how many are sidelined or blockaded from entry. The dynamic games lead to systems of nonlinear partial differential equations for which we discuss asymptotic and numerical approximations. Applications include competition between energy producers in the face of exhaustible resources such as oil (Cournot); and markets for substitutable consumer goods (Bertrand).
Ronnie Sircar (Princeton University) Dynamic oligopolies and differential games. II
Abstract: No Abstract
Saverio Eric Spagnolie (University of California, San Diego) Swimming at low and intermediate Reynolds number
Abstract: A number of findings from recent works are presented. At intermediate Reynolds number, where both inertia and viscous dissipation are important, we have observed through experiment and numerical simulation a number of counter-intuitive behaviors in a flapping wing system with passive pitching [joint work with L. Moret, M. Shelley, and J. Zhang]. The behavior of shape-changing bodies are also considered, along with consequences on vortex shedding and vortex-interaction dynamics, driven either by a recoil force from internal oscillations (recoil) or by an external background flow (hovering) [joint work with M. Shelley, S. Childress, and T. Tokieda]. Other problems are investigated at low Reynolds number, where viscous dissipation dominates inertial effects. These include the effects of elastic bending costs on the optimal swimming shape of slender bodies, the locomotion of bilayer vesicles, and the swimming behavior and efficiency of a fluid-extruding body ("jet propulsion") at zero Reynolds number [joint work with E. Lauga and A. Evans].
Saverio Eric Spagnolie (University of California, San Diego) Jet propulsion without inertia
Abstract: A body immersed in a highly viscous fluid can locomote by drawing in and expelling fluid through pores at its surface. We consider this mechanism of jet propulsion without inertia in the case of spheroidal bodies, and derive both the swimming velocity and the hydrodynamic efficiency. Elementary examples are presented, and exact axisymmetric solutions for spherical, prolate spheroidal, and oblate spheroidal body shapes are provided. In each case, entirely and partially porous (i.e. jetting) surfaces are considered, and the optimal jetting flow profiles at the surface for maximizing the hydrodynamic efficiency are determined computationally. The maximal efficiency which may be achieved by a sphere using such jet propulsion is 12.5%, a significant improvement upon traditional flagella-based means of locomotion at zero Reynolds number. Unlike other swimming mechanisms which rely on the presentation of a small cross section in the direction of motion, the efficiency of a jetting body at low Reynolds number increases as the body becomes more oblate, and limits to approximately 162% in the case of a flat plate swimming along its axis of symmetry. Our results are discussed in the light of slime extrusion mechanisms occurring in many cyanobacteria. (Joint work with E. Lauga)
Wanda Strychalski (University of California, Davis) A computational model of bleb formation
Abstract: Blebbing occurs when the cytoskeleton detaches from the cell membrane, resulting in the pressure-driven flow of cytosol towards the area of detachment and the local expansion of the cell membrane. Recent interest has focused metastatic cancer cells that use blebs for cell motility. We present a dynamic computational model of the cell that includes mechanics of and the interactions between the intracellular fluid, the actin cortex, and the cell membrane. The cortex is an active, elastic, permeable material, which moves with a velocity distinct from that of the background fluid. The Immersed Boundary Method is modified to account for the relative motion between the cortex and the fluid. The computational model is used to explore several hypotheses for bleb formation, and these simulations are compared to experimental results. Additionally, a pressure threshold for bleb initiation, which depends crucially on the constitutive law for the membrane, is predicted based on reduced analytic models. These predictions are further explored in the full computational model and identified with underlying cellular processes.
Susan S. Suarez (Cornell University) Unsolved problems in the locomotion of mammalian sperm
Abstract: In order to develop better methods for diagnosis and treatment of infertility, as well as safer contraceptives, more must be learned about how mammalian sperm move through the female reproductive tract. Crucial phases of mammalian sperm transport include passage through the cervix and uterotubal junction, storage of sperm in the oviductal storage reservoir, release from the reservoir, and location of the egg. There is some evidence for the existence of special passageways for sperm in the cervix, but this needs to be demonstrated and the mechanism of guiding sperm through the cervix needs to be elucidated. Passage of sperm through the uterotubal junction requires sperm to have certain proteins, but how these proteins function is not known. There is evidence that sperm must undergo motility hyperactivation in order to be released from the oviductal storage reservoir; however, the process is not understood. Finally, it is not clear whether there are chemotactic agents that emanate from the vicinity of the egg to modulate sperm flagellar beating patterns in order to guide them toward the egg. There are three main areas in which bioengineers can provide crucial help for elucidating these mysteries: (1) by developing a method for measuring and comparing sperm flagellar bending patterns, (2) by improving optical equipment for viewing the movement of sperm within the female reproductive tract, and (3) by developing chambers that mimic the physical environment of the tract so that molecular mechanisms that regulate sperm movement can be elucidated. USDA CSREES NRICGP 2008-35203-19031 and NIH 1RO3HD062471-01.
Susan S. Suarez (Cornell University) Distinct Ca2+ signaling pathways turn mouse sperm in opposite directions
Abstract: Joint work with Haixin Chang (Cornell University) . Hyperactivation, a swimming pattern used by mammalian sperm in the oviduct, is essential for fertilization. It is characterized by highly asymmetrical flagellar beating and an increase of cytoplasmic Ca2+. We observed that some mouse sperm swimming in the oviduct produce high-amplitude pro-hook bends (bends in the direction of the hook on the head) while others produce high-amplitude anti-hook bends. Switching direction of the high-amplitude bends could serve to re-direct sperm toward oocytes. Our objective was to test the hypothesis that different Ca2+ cell signaling pathways produce pro-hook and anti-hook patterns. In vitro, sperm that hyperactivated during capacitation (a process that prepares sperm for fertilization) swam using large pro-hook bends, which resulted from influx of Ca2+ through plasma membrane CatSper channels. The anesthetic procaine and the K+-channel blocker 4-Aminopyridine (4-AP) also each induced large pro-hook bends. In contrast, thimerosal, which triggers Ca2+ release from an intracellular Ca2+ storage site, induced large anti-hook bends. When capacitated sperm were treated with thimerosal, 90% switched from pro-hook to anti-hook bending. Sperm loaded with the fluorescent Ca2+ indicator Fluo-4 AM revealed that thimerosal initiated a Ca2+ increase at the base of the flagellum, while 4-AP initiated an increase in the principal piece of the flagellum. Proteins were extracted from sperm for examination of phosphorylation patterns induced by Ca2+ signaling. Procaine and 4-AP treatments phosphorylated threonine and serine residues of some proteins, whereas thimerosal treatment dephosphorylated some proteins. Tyrosine phosphorylation was unaffected. We concluded that pro-hook hyperactivation, associated with sperm capacitation, can be modulated by a distinct Ca2+ signaling system to re-direct sperm toward oocytes. NIH 1R03HD062471-01.
Daniel See-Wai Tam (Massachusetts Institute of Technology) Dynamics of passive flexible wings
Abstract: Seed dispersal is the means by which plants expand and colonize new areas. To maximize their range, some plants have developed elaborate gliding, spinning or tumbling winged seedpods, whose aerodynamics enable them to extend their flight time and range. Such winged seedpods are often light and thin, which generally decreases their surface loading and hence their rate of descent. As a consequence, they can be flexible. We are broadly interested in elucidating the role of flexibility in passive flight. The influence of flexibility on the flight of autorotating winged seedpods is examined through an experimental investigation of tumbling rectangular paper strips freely falling in air. Our results suggest the existence of a critical length above which the wing bends. We develop a theoretical model that demonstrates that this buckling is prompted by inertial forces associated with the tumbling motion, and yields a buckling criterion consistent with that observed. We further develop a reduced model for the flight dynamics of flexible tumbling wings that illustrates the effect of aeroelastic coupling on flight characteristics and rationalizes experimentally observed variations in the wing's falling speed and range.
Russ Tedrake (Massachusetts Institute of Technology) Algorithms for nonlinear analysis, optimization, and control of locomotion
Abstract: Keywords: locomotion, motion planning, verification, control, robotic birds, perching Abstract: Locomotion in fluids (and on terrain) often involves complex nonlinear dynamics and non-trivial notions of stability including limit cycles and dynamically stable maneuvers. In this talk I will describe some new algorithms for automatically verifying stability (via a Lyapunov function) and estimating regions of attraction for dynamic nonlinear locomotion. These tools have important implications for motion planning and feedback design, which I will demonstrate by describing our attempts to build robots that fly like a bird and execute post- stall maneuvers to land on a perch.
Nizar Touzi (École Polytechnique) Stochastic target problems and viscosity solutions
Abstract: No Abstract
Nizar Touzi (École Polytechnique) Second order stochastic target problems
Abstract: No Abstract
Nizar Touzi (École Polytechnique) Backward stochastic differential equations and connection with semilinear PDEs
Abstract: No Abstract
Nizar Touzi (École Polytechnique) Second order backward stochastic differential equations and connection with fully nonlinear PDEs
Abstract: No Abstract
Nizar Touzi (École Polytechnique) Numerical methods for BSDEs and applications
Abstract: No Abstract
Marius Tucsnak (Université de Nancy I (Henri Poincaré)) Controllability by the shape of a low Reynolds number swimmer
Abstract: No Abstract
Jane Wang (Cornell University) Tutorial: Introduction to insect flight
Abstract: No Abstract
Sheng Xu (Southern Methodist University) Coupling the Newton dynamics and aerodynamics of insect flight in the immersed interface method
Abstract: I will first give an brief overview of the immersed interface method for fluid-solid interaction. I will then focus on the application of the method to numerical simulation of insect flight. In particular, I will present (1) a boundary condition capturing approach for the prescribed kinematics of an insect wing, (2) a matrix formulation of the Newton dynamics for insect flight, and (3) a coupling approach to couple the aerodynamics and Newton dynamics of insect flight.
Jeannette Yen (Georgia Institute of Technology) Kinematics of various swimming modes in Antarctic krill
Abstract: Joint work with D. W. Murphy1, D.R. Webster1, S. Kawaguchi2, R. King2, and F. Sotiropoulos3. The locomotion of Antarctic krill (Euphausia superba) is known to depend on the metachronal paddling of the animal’s five pairs of pleopods. A wave passing along these swimming appendages from posterior to anterior transfers momentum to the surrounding fluid, thus producing thrust. The kinematics of these pleopods, however, have not been fully characterized. Determining the kinematics of krill in various swimming modes will shed light on the fluid mechanics of krill locomotion and thereby deepen our understanding of krill sensing and schooling. High speed footage (250 fps) of freely swimming juvenile and adult Antarctic krill was acquired at the Australian Antarctic Division in Hobart, Tasmania. Various swimming modes were identified based on swimming angle and behavior, and two-dimensional kinematic parameters such as pleopod stroke frequency, amplitude, stroke overlap, and animal velocity were investigated as a function of these swimming modes. The variability of these parameters over time provides insight into the high sensitivity and responsiveness of krill to their hydrodynamic environment. Useful comparisons can also be made to previously gathered kinematics data for pacific krill (Euphausia pacifica), which live in a much lower viscosity environment. These parameters will prove necessary in future computational fluid dynamics (CFD) simulations of krill locomotion. 1 School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, GA 30332-0355 USA
2 Australian Antarctic Division, Kingston, Tasmania, Australia 7050
3 Saint Anthony Falls Laboratory, University of Minnesota, Minneapolis, MN 55414
Jianfeng Zhang (University of Southern California) Martingale representation theorem for the G-expectation
Abstract: In recent years Peng prososed a new notion called G-expectation, a type of nonlinear expectation motivated from dynamic risk measures with volatility uncertainty. On the other hand, a martingale under the G-expectation can be viewed as the solution to a "linear" Second Order Backward SDEs, the main subject of the short course which will be given by Nizar Touzi in this workshop. The theory has applications in many areas, e.g. Monte Carlo methods for fully nonlinear PDEs, finanancial problems in models with volatility uncertainty (volatility control, liquidity cost, Gamma constraint). Its main technical feature is the quasi-sure stochastic analysis, which invloves a class of mutually singular probability measures. In this talk we will introduce G-martingales, develop the quais-sure stochastic analysis, and establish the martingale epresentation theorem for G-martingales. This is a joint work with Mete Soner and Nizar Touzi.
Qiang Zhu (University of California, San Diego) Performance of ray fins in fish locomotion
Abstract: Joint work with Kourosh Shoele, Dept of Structural Engr, UCSD. Fins of bony fishes are characterized by a skeleton-reinforced membrane structure consisting of a soft collagen membrane strengthened by embedded flexible rays. Morphologically, each ray is connected to a group of muscles so that the fish can control the rotational motion of each ray individually, enabling multi-degree of freedom control over the fin motion and deformation. We have developed a fluid-structure interaction model to simulate the kinematics and dynamic performance of a structurally idealized fin. This method includes a boundary-element model of the fluid motion and a fully-nonlinear Euler-Bernoulli beam model of the embedded rays. Using this model we studied thrust generation and propulsion efficiency of the fin at different combinations of parameters. Effects of kinematic as well as structural properties are examined. It has been illustrated that the fish’s capacity to control the motion of each individual ray, as well as the anisotropic deformability of the fin determined by distribution of the rays (especially the detailed distribution of ray stiffness), are essential to high propulsion performance. Finally, we note that this structural design is a recurring motif in nature. Several similar biostructures will be discussed.
Visitors in Residence
Vittorio Addona Macalester College 6/30/2010 - 7/2/2010
Dhanapati Adhikari Oklahoma State University 5/31/2010 - 6/6/2010
Olcay Akman Illinois State University 6/29/2010 - 7/2/2010
Silas Alben Georgia Institute of Technology 6/1/2010 - 6/5/2010
Alexander Alexeev Georgia Institute of Technology 5/31/2010 - 6/5/2010
Arezoo Ardekani Massachusetts Institute of Technology 5/31/2010 - 6/5/2010
Giles Auchmuty University of Houston 6/23/2010 - 6/25/2010
Nusret Balci University of Minnesota 9/1/2009 - 8/31/2010
Erhan Bayraktar University of Michigan 6/9/2010 - 6/18/2010
Tsevi Beatus Cornell University 5/31/2010 - 6/5/2010
Arjun Beri University of Houston 6/6/2010 - 6/18/2010
Gordon Joseph Berman Princeton University 5/31/2010 - 6/5/2010
Andrew Beveridge Macalester College 6/14/2010 - 7/16/2010
Tracy Bibelnieks Augsburg College 6/30/2010 - 7/2/2010
Steven Bleiler Portland State University 6/6/2010 - 6/18/2010
Albert Boggess Texas A & M University 6/23/2010 - 6/25/2010
Adam Boucher University of New Hampshire 5/31/2010 - 6/6/2010
Luca Brandt Royal Institute of Technology (KTH) 5/31/2010 - 6/7/2010
Kenny Breuer Brown University 5/31/2010 - 6/4/2010
Jared C. Bronski University of Illinois at Urbana-Champaign 6/23/2010 - 6/25/2010
Russell Brown University of Kentucky 6/23/2010 - 6/25/2010
Michael Bulmer University of Queensland 6/29/2010 - 7/2/2010
Leslie Button Corning Incorporated 6/21/2010 - 6/25/2010
Maria-Carme T. Calderer University of Minnesota 9/1/2009 - 6/30/2010
James Caristi Valparaiso University 6/29/2010 - 7/2/2010
Guillaume Carlier Université de Paris-Dauphine 6/6/2010 - 6/13/2010
Rene Carmona Princeton University 6/6/2010 - 6/18/2010
Chi Hin Chan University of Minnesota 9/1/2009 - 8/31/2010
Feng Chen Purdue University 6/6/2010 - 6/18/2010
Guangliang Chen University of Minnesota 6/13/2010 - 6/24/2010
Xianjin Chen University of Minnesota 9/1/2008 - 8/31/2010
Huibin Cheng University of Pittsburgh 6/6/2010 - 6/18/2010
Laura Chihara Carleton College 6/14/2010 - 7/16/2010
Stephen Childress New York University 5/9/2010 - 6/6/2010
Howie Choset Carnegie Mellon University 6/3/2010 - 6/3/2010
Luis H. Cisneros University of Arizona 5/31/2010 - 6/5/2010
Myriam Cisneros Mexican Petroleum Institute 6/6/2010 - 6/18/2010
Julie M Clark Hollins University 6/29/2010 - 7/3/2010
Robert Coffman University of Wisconsin-River Falls 6/30/2010 - 7/2/2010
Fredric S Cohen Rush University Medical Center 5/31/2010 - 6/5/2010
Itai Cohen Cornell University 5/31/2010 - 6/6/2010
Peter Constantin University of Chicago 6/23/2010 - 6/25/2010
Aline J. Cotel University of Michigan 5/31/2010 - 6/5/2010
Darren G. Crowdy Imperial College London 5/31/2010 - 6/3/2010
Zhenlu Cui Fayetteville State University 5/31/2010 - 6/5/2010
Eric Cytrynbaum University of British Columbia 6/29/2010 - 7/3/2010
John O. Dabiri California Institute of Technology 6/1/2010 - 6/3/2010
Domenico D'Alessandro Iowa State University 4/15/2010 - 6/30/2010
Isabel K. Darcy University of Iowa 6/29/2010 - 7/2/2010
Jennifer L. Davidson Iowa State University 6/23/2010 - 6/25/2010
Robert Claude delMas University of Minnesota 6/30/2010 - 7/2/2010
Mark Denny Stanford University 5/31/2010 - 6/4/2010
Antonio DeSimone International School for Advanced Studies (SISSA/ISAS) 5/31/2010 - 6/4/2010
Luca Dieci Georgia Institute of Technology 6/23/2010 - 6/25/2010
Charles R. Doering University of Michigan 8/15/2009 - 6/10/2010
Tobin A. Driscoll University of Delaware 6/23/2010 - 6/25/2010
Oguz C. Durumeric University of Iowa 6/23/2010 - 6/25/2010
Deborah Edmund University of Michigan 5/31/2010 - 6/4/2010
Robert S. Eisenberg Rush University Medical Center 5/31/2010 - 6/5/2010
Ivar Ekeland University of British Columbia 6/9/2010 - 6/12/2010
Saber Elaydi Trinity University 6/29/2010 - 7/2/2010
Jeff D. Eldredge University of California, Los Angeles 5/31/2010 - 6/5/2010
Acmae El Yacoubi Cornell University 5/30/2010 - 6/4/2010
Julius Njome Esunge University of Mary Washington 6/6/2010 - 6/18/2010
Randy H. Ewoldt University of Minnesota 9/1/2009 - 8/31/2010
Emilie Ghislaine Gabrielle Fabre École Polytechnique 6/13/2010 - 6/20/2010
Robert Falgout Lawrence Livermore National Laboratory 6/23/2010 - 6/25/2010
Lisa J. Fauci Tulane University 5/31/2010 - 6/6/2010
Max Fehr London School of Economics and Political Science 6/5/2010 - 6/10/2010
Frank E. Fish West Chester University 5/31/2010 - 6/5/2010
Daniel Flath Macalester College 6/7/2010 - 7/16/2010
Hermes Gadêlha University of Oxford 5/30/2010 - 6/6/2010
Eamonn Andrew Gaffney University of Oxford 5/31/2010 - 6/6/2010
Albert Gilg Siemens 6/23/2010 - 6/25/2010
John Ginder Ford 6/23/2010 - 6/25/2010
Mark S. Gockenbach Michigan Technological University 6/23/2010 - 6/25/2010
Daniel Ivan Goldman Georgia Institute of Technology 5/31/2010 - 6/5/2010
Christophe Golé Smith College 6/29/2010 - 7/2/2010
Michael D. Graham University of Wisconsin 5/31/2010 - 6/5/2010
Olaf Hall-Holt St. Olaf College 6/14/2010 - 7/16/2010
Bernard Harris Northern Illinois University 6/23/2010 - 6/25/2010
Andong He Pennsylvania State University 5/30/2010 - 6/5/2010
Bruce Hendrickson Sandia National Laboratories 6/23/2010 - 6/25/2010
Alex A Himonas University of Notre Dame 6/6/2010 - 6/18/2010
Christel Hohenegger New York University 6/1/2010 - 6/5/2010
Nicholas Jon Horton Smith College 6/29/2010 - 7/2/2010
Natali Hritonenko Prairie View A&M University 6/6/2010 - 6/18/2010
Bei Hu University of Notre Dame 6/23/2010 - 6/25/2010
David Hu Georgia Institute of Technology 5/31/2010 - 6/5/2010
Jifeng Hu University of Minnesota 6/1/2010 - 6/5/2010
Xianpeng Hu University of Pittsburgh 5/31/2010 - 6/5/2010
Junming Huang University of Pittsburgh 6/6/2010 - 6/19/2010
Yan Huang Macalester College 6/13/2010 - 7/17/2010
Yu-Jui Huang University of Michigan 6/6/2010 - 6/18/2010
Yunkyong Hyon University of Minnesota 9/1/2008 - 8/31/2010
Rebekah R Isaak University of Minnesota 6/30/2010 - 7/2/2010
Volkan Isler University of Minnesota 6/14/2010 - 7/16/2010
Mark Iwen University of Minnesota 9/1/2008 - 7/31/2010
Pieter Jan Antoon Janssen University of Wisconsin 5/31/2010 - 6/5/2010
Srividhya Jeyaraman University of Minnesota 9/1/2008 - 6/8/2010
Lijian Jiang University of Minnesota 9/10/2008 - 8/31/2010
Mihailo Jovanovic University of Minnesota 9/11/2009 - 6/10/2010
Ning Ju Oklahoma State University 1/4/2010 - 6/25/2010
Sunghwan (Sunny) Jung Virginia Polytechnic Institute and State University 5/31/2010 - 6/3/2010
Eva Kanso University of Southern California 5/31/2010 - 6/5/2010
Daniel Kaplan Macalester College 6/30/2010 - 7/2/2010
Catherine G Kealey Beloit College 6/13/2010 - 7/16/2010
Markus Keel University of Minnesota 7/21/2008 - 6/30/2010
Changho Keem Seoul National University 6/19/2010 - 7/3/2010
Scott David Kelly University of North Carolina - Charlotte 5/31/2010 - 6/5/2010
Elisabeth Teudjeu Kemajou Southern Illinois University 6/7/2010 - 6/19/2010
Kimberly D. Kendricks Central State University 5/10/2010 - 7/19/2010
Boguk Kim University of Wisconsin 6/6/2010 - 6/18/2010
Hyejin Kim University of Minnesota 9/1/2009 - 8/31/2010
Jeff Randall Knisley East Tennessee State University 6/29/2010 - 7/2/2010
Mimi Koehl University of California, Berkeley 6/2/2010 - 6/4/2010
Pawel Konieczny University of Minnesota 9/1/2009 - 8/31/2010
Don Kreher Michigan Technological University 6/29/2010 - 7/2/2010
Arshad Kudrolli Clark University 6/1/2010 - 6/4/2010
Devadatta Kulkarni General Motors 6/23/2010 - 6/25/2010
Christopher Kuster Carroll University 6/29/2010 - 7/2/2010
Amy Lang University of Alabama 5/31/2010 - 6/5/2010
Ronald G. Larson University of Michigan 6/1/2010 - 6/5/2010
Eric Lauga University of California, San Diego 5/31/2010 - 6/4/2010
Anita Layton Duke University 5/31/2010 - 6/5/2010
Chiun-Chang Lee National Taiwan University 10/22/2009 - 6/9/2010
David Lentink Wageningen University and Research Center 5/31/2010 - 6/5/2010
Gilad Lerman University of Minnesota 6/14/2010 - 7/16/2010
Rachel Levy Harvey Mudd College 5/31/2010 - 6/5/2010
Marta Lewicka University of Minnesota 9/1/2009 - 6/30/2010
Congming Li University of Colorado 1/11/2010 - 6/15/2010
Jenny Li Pennsylvania State University 6/6/2010 - 6/13/2010
Wanyi Li Macalester College 6/14/2010 - 7/16/2010
Yongfeng Li University of Minnesota 9/1/2008 - 8/31/2010
Zhi (George) Lin University of Minnesota 9/1/2009 - 8/31/2010
Bin Liu New York University 5/31/2010 - 6/5/2010
Chun Liu University of Minnesota 9/1/2008 - 8/31/2010
Kun Liu Rice University 6/6/2010 - 6/18/2010
Jerome Loheac Université de Nancy I (Henri Poincaré) 5/31/2010 - 6/6/2010
Ellen K. Longmire University of Minnesota 9/1/2009 - 6/30/2010
Juan Lopez Arizona State University 6/23/2010 - 6/25/2010
Michael Ludkovski University of California, Santa Barbara 6/16/2010 - 6/18/2010
Evelyn Manalo Lunasin University of Arizona 5/25/2010 - 6/12/2010
Enkeleida Lushi New York University 5/31/2010 - 6/5/2010
Suping Lyu Medtronic 6/24/2010 - 6/24/2010
Krishnan Mahesh University of Minnesota 9/1/2009 - 6/30/2010
Kara Lee Maki University of Minnesota 9/1/2009 - 8/31/2010
Eric Marland Appalachian State University 6/29/2010 - 7/2/2010
Vasileios Maroulas University of Minnesota 9/1/2008 - 7/31/2010
Hassan Masoud Georgia Institute of Technology 5/31/2010 - 6/5/2010
Aaron J Maurer Carleton College 6/13/2010 - 7/16/2010
Anna L. Mazzucato Pennsylvania State University 1/12/2010 - 6/11/2010
Anna L. Mazzucato Pennsylvania State University 6/24/2010 - 6/24/2010
John M McCauley Haverford College 6/13/2010 - 7/17/2010
Richard P. McGehee University of Minnesota 6/30/2010 - 6/30/2010
Piotr Mikusinski University of Central Florida 6/23/2010 - 6/25/2010
Laura Ann Miller University of North Carolina 5/31/2010 - 6/5/2010
Michal Mlejnek Corning Incorporated 5/31/2010 - 6/5/2010
Kamran Mohseni University of Colorado 5/31/2010 - 6/2/2010
Donna Molinek Davidson College 6/29/2010 - 7/2/2010
Yoichiro Mori University of Minnesota 9/1/2009 - 6/30/2010
Roman Muraviev ETH 6/9/2010 - 6/19/2010
Richard D. Neidinger Davidson College 6/29/2010 - 7/2/2010
Hoa Nguyen Tulane University 5/31/2010 - 6/6/2010
Monika Nitsche University of New Mexico 5/31/2010 - 6/5/2010
Dongjuan Niu Capital Normal University 4/1/2010 - 6/15/2010
Clara O'Farrell California Institute of Technology 5/30/2010 - 6/5/2010
Sarah Olson Tulane University 5/31/2010 - 6/5/2010
Peter J. Olver University of Minnesota 6/23/2010 - 6/25/2010
Yizhar Or Technion-Israel Institute of Technology 5/31/2010 - 6/6/2010
Cecilia Ortiz-Duenas University of Minnesota 9/1/2009 - 8/31/2010
Hans G. Othmer University of Minnesota 9/1/2009 - 6/30/2010
Mary Therese Padberg University of Iowa 6/29/2010 - 7/2/2010
Mavis Pararai Indiana University of Pennsylvania 6/7/2010 - 6/19/2010
Jiyoon Park University of Minnesota 6/30/2010 - 7/2/2010
Neelesh A. Patankar Northwestern University 6/2/2010 - 6/5/2010
Michael Pearson Mathematical Association of America (MAA) 6/30/2010 - 7/2/2010
Jifeng Peng University of Alaska 6/1/2010 - 6/5/2010
Peter Polyakov University of Wyoming 6/23/2010 - 6/25/2010
Dylan Possamai École Polytechnique 6/13/2010 - 6/18/2010
Candice Renee Price University of Iowa 6/29/2010 - 7/2/2010
Randall Pruim Calvin College 6/29/2010 - 7/2/2010
Yuan-Wei Qi University of Central Florida 6/6/2010 - 6/13/2010
Juan Mario Restrepo University of Arizona 8/11/2009 - 6/15/2010
Leif Gibbens Ristroph Cornell University 5/31/2010 - 6/5/2010
John William Roberts Massachusetts Institute of Technology 5/31/2010 - 6/5/2010
Beatriz Rumbos Instituto Tecnologico Autonomo de Mexico 6/6/2010 - 6/18/2010
Rolf Ryham Rice University 5/13/2010 - 6/15/2010
David Saintillan University of Illinois at Urbana-Champaign 5/31/2010 - 6/5/2010
Tariq Samad, Corporate Fellow Honeywell 6/23/2010 - 6/25/2010
Bjorn Sandstede Brown University 6/30/2010 - 7/2/2010
Fadil Santosa University of Minnesota 7/1/2008 - 6/30/2011
Vishal Saraswat University of Minnesota 6/13/2010 - 7/16/2010
Arnd Scheel University of Minnesota 9/1/2009 - 6/30/2010
William W. Schultz University of Michigan 5/28/2010 - 6/5/2010
George R Sell University of Minnesota 9/1/2009 - 6/30/2010
Tsvetanka Sendova University of Minnesota 9/1/2008 - 8/31/2010
Chehrzad Shakiban University of Minnesota 6/23/2010 - 6/25/2010
Shuanglin Shao University of Minnesota 9/1/2009 - 8/31/2010
David H. Sharp Los Alamos National Laboratory 6/23/2010 - 6/25/2010
Michael J. Shelley New York University 6/1/2010 - 6/5/2010
Jian Sheng University of Minnesota 6/1/2010 - 6/5/2010
Sung-Chan Shin Korea Advanced Institute of Science and Technology (KAIST) 6/4/2010 - 6/19/2010
Ratnasingham Shivaji Mississippi State University 6/23/2010 - 6/25/2010
Gregory Shubin Boeing 6/23/2010 - 6/25/2010
Henry Shum University of Oxford 5/31/2010 - 6/5/2010
Ronnie Sircar Princeton University 6/13/2010 - 6/18/2010
Jake Socha Virginia Polytechnic Institute and State University 5/31/2010 - 6/3/2010
Saverio Eric Spagnolie University of California, San Diego 5/31/2010 - 6/6/2010
Adam Spiegler Loyola University 6/29/2010 - 7/2/2010
Konstantinos Spiliopoulos Brown University 6/6/2010 - 6/18/2010
Daniel Spirn University of Minnesota 9/8/2009 - 6/1/2010
Katie St. Clair Carleton College 6/30/2010 - 7/2/2010
Peter J. Sternberg Indiana University 6/23/2010 - 6/25/2010
Panagiotis Stinis University of Minnesota 9/1/2009 - 6/30/2010
Robert Mills Strain III University of Pennsylvania 6/23/2010 - 6/25/2010
Wanda Strychalski University of California, Davis 5/31/2010 - 6/5/2010
Susan S. Suarez Cornell University 5/31/2010 - 6/5/2010
Patrick Sullivan Valparaiso University 6/29/2010 - 7/2/2010
Vladimir Sverak University of Minnesota 9/1/2009 - 6/30/2010
Charles L Talbot University of Connecticut 6/14/2010 - 7/16/2010
Daniel See-Wai Tam Massachusetts Institute of Technology 5/31/2010 - 6/5/2010
Jeff Tecosky-Feldman Haverford College 6/29/2010 - 7/2/2010
Russ Tedrake Massachusetts Institute of Technology 5/31/2010 - 6/5/2010
Jean-Luc Thiffeault University of Wisconsin 9/1/2009 - 6/14/2010
Becca Thomases University of California, Davis 2/9/2010 - 6/12/2010
Giordano Tierra Chica University of Sevilla 4/6/2010 - 6/15/2010
Nathan Tintle Hope College 6/29/2010 - 7/2/2010
Edriss Saleh Titi University of California 3/28/2010 - 6/12/2010
Anthony Tongen James Madison University 6/29/2010 - 7/1/2010
Chad Michael Topaz Macalester College 9/1/2009 - 6/29/2010
Chad Michael Topaz Macalester College 6/30/2010 - 7/2/2010
Nizar Touzi École Polytechnique 6/14/2010 - 6/18/2010
Marius Tucsnak Université de Nancy I (Henri Poincaré) 5/30/2010 - 6/6/2010
Gunther A. Uhlmann University of Washington 6/20/2010 - 6/23/2010
Patrick Theodore Underhill Rensselaer Polytechnic Institute 5/31/2010 - 6/5/2010
Silviya D Valeva Mount Holyoke College 6/14/2010 - 7/16/2010
Eric van den Berg Telcordia 6/23/2010 - 6/25/2010
Peter B VanKoughnett Oberlin College 6/14/2010 - 7/16/2010
Peter Veerman Portland State University 6/23/2010 - 6/25/2010
Lalitha Venkataramanan Schlumberger-Doll 6/23/2010 - 6/25/2010
Steven Vogel Duke University 5/31/2010 - 6/5/2010
Shawn W. Walker New York University 5/30/2010 - 6/5/2010
Changyou Wang University of Kentucky 9/1/2009 - 6/15/2010
Jane Wang Cornell University 5/30/2010 - 6/5/2010
Qixuan Wang University of Minnesota 6/1/2010 - 6/5/2010
Yang Wang Michigan State University 6/23/2010 - 6/25/2010
Paul W. Webb University of Michigan 5/31/2010 - 6/5/2010
Yan Wei Michigan State University 6/6/2010 - 6/18/2010
Nathaniel Whitaker University of Massachusetts 5/31/2010 - 6/5/2010
Andrew J W White St. Olaf College 6/14/2010 - 7/16/2010
Sijue Wu University of Michigan 9/1/2009 - 6/5/2010
Yulong Xing University of Tennessee 6/23/2010 - 6/25/2010
Wei Xiong University of Minnesota 9/1/2008 - 8/31/2010
Jin Xu Shanghai University of Traditional Chinese Medicine 12/9/2009 - 6/9/2010
Sheng Xu Southern Methodist University 5/31/2010 - 6/5/2010
Xiang Xu Pennsylvania State University 1/13/2010 - 6/13/2010
Yuri Yatsenko Houston Baptist University 6/6/2010 - 6/18/2010
Jeannette Yen Georgia Institute of Technology 5/31/2010 - 6/5/2010
Tsuyoshi Yoneda University of Minnesota 9/4/2009 - 8/31/2010
Jianfeng Zhang University of Southern California 6/14/2010 - 6/16/2010
Jun Zhang New York University 5/31/2010 - 6/6/2010
Shiju Zhang St. Cloud State University 6/29/2010 - 7/2/2010
Peiyi Zhao St. Cloud State University 6/29/2010 - 7/2/2010
Weigang Zhong University of Minnesota 9/8/2008 - 9/30/2010
Qiang Zhu University of California, San Diego 5/31/2010 - 6/5/2010
Andrew Zieffler University of Minnesota 6/30/2010 - 7/2/2010
Paul Zorn St. Olaf College 6/14/2010 - 7/16/2010
Legend: Postdoc or Industrial Postdoc Long-term Visitor

IMA Affiliates:
Arizona State University, Boeing, Corning Incorporated, ExxonMobil, Ford, General Motors, Georgia Institute of Technology, Honeywell, IBM, Indiana University, Iowa State University, Korea Advanced Institute of Science and Technology (KAIST), Lawrence Livermore National Laboratory, Lockheed Martin, Los Alamos National Laboratory, Medtronic, Michigan State University, Michigan Technological University, Mississippi State University, Northern Illinois University, Ohio State University, Pennsylvania State University, Portland State University, Purdue University, Rice University, Rutgers University, Sandia National Laboratories, Schlumberger Cambridge Research, Schlumberger-Doll, Seoul National University, Siemens, Telcordia, Texas A & M University, University of Central Florida, University of Chicago, University of Delaware, University of Houston, University of Illinois at Urbana-Champaign, University of Iowa, University of Kentucky, University of Maryland, University of Michigan, University of Minnesota, University of Notre Dame, University of Pennsylvania, University of Pittsburgh, University of Tennessee, University of Wisconsin, University of Wyoming, US Air Force Research Laboratory, Wayne State University, Worcester Polytechnic Institute