BEGIN:VCALENDAR
PRODID:-//PSU Mathematics Department//Seminar iCalendar Generator//EN
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CALSCALE:GREGORIAN
METHOD:PUBLISH
X-WR-CALNAME:Computational and Applied Mathematics Colloquium
X-WR-TIMEZONE:America/New_York
BEGIN:VTIMEZONE
TZID:America/New_York
X-LIC-LOCATION:America/New_York
BEGIN:DAYLIGHT
TZOFFSETFROM:-0500
TZOFFSETTO:-0400
TZNAME:EDT
DTSTART:19700308T020000
RRULE:FREQ=YEARLY;BYMONTH=3;BYDAY=2SU
END:DAYLIGHT
BEGIN:STANDARD
TZOFFSETFROM:-0400
TZOFFSETTO:-0500
TZNAME:EST
DTSTART:19701101T020000
RRULE:FREQ=YEARLY;BYMONTH=11;BYDAY=1SU
END:STANDARD
END:VTIMEZONE
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20140113T143000
DTEND;TZID=America/New_York:20140113T153000
LOCATION:MB106
URL:http://www.math.psu.edu/seminars/meeting.php?id=19122
SUMMARY:Computational and Applied Mathematics Colloquium - Linear Theory fo
r Filtering Nonlinear Multiscale Systems with Model Error
DESCRIPTION:Seminar: Computational and Applied Mathematics Colloquium\nTitl
e: Linear Theory for Filtering Nonlinear Multiscale Systems with Model Err
or\nSpeaker: John Harlim\, Pennsylvania State University\nAbstract Link: h
ttp://www.personal.psu.edu/jzh13/\nAbstract: Fundamental issues in improvi
ng state estimation (or filtering) problems are model errors. This problem
is attributed to incomplete understanding of the underlying physics and o
ur lack of computational resources to resolve physical processes in variou
s time and length scales. In this talk\, we will discuss a linear theory f
or filtering multiscale dynamical systems with model error. In particular
\, we will use the notion of "consistency" to show the existence and uniqu
eness of an optimal filter with a reduced stochastic model. By optimality
\, we mean both the posterior mean and covariance estimates from the reduc
ed filter matches the true filtered statistical solutions. Subsequently\,
we will construct an accurate reduced filter in a simple\, yet challenging
nonlinear setting\, where the optimal filter is not available as in pract
ical situation. Finally\, we will discuss a stochastic parameterization st
rategy to account for model errors in filtering high-dimensional nonlinear
problems. We will demonstrate our stochastic parameterization method in a
numerical example by filtering an 81-dimensional model which exhibits man
y of the characteristics seen in practical applications using a 9-dimensio
nal reduced model.
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20140120T143000
DTEND;TZID=America/New_York:20140120T153000
LOCATION:MB106
URL:http://www.math.psu.edu/seminars/meeting.php?id=19123
SUMMARY:Computational and Applied Mathematics Colloquium - No seminar
DESCRIPTION:Seminar: Computational and Applied Mathematics Colloquium\nTitl
e: No seminar
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20140127T143000
DTEND;TZID=America/New_York:20140127T153000
LOCATION:MB106
URL:http://www.math.psu.edu/seminars/meeting.php?id=19124
SUMMARY:Computational and Applied Mathematics Colloquium - Initial and boun
dary value problems for the equations of the climate without viscosity: pr
imitive equations and shallow water equations.
DESCRIPTION:Seminar: Computational and Applied Mathematics Colloquium\nTitl
e: Initial and boundary value problems for the equations of the climate wi
thout viscosity: primitive equations and shallow water equations.\nSpeaker
: Cancelled due to weather: Roger Temam\, Indiana University--Bloomington
\nAbstract Link: http://mypage.iu.edu/~temam/\nAbstract: In this lecture w
e will first briefly show how the inviscid two-dimensional Shallow Water (
SW) equations relate to the Primitive Equations of the atmosphere and the
oceans\, in the context of the so-called Limited Area Models (LAM). We wil
l then survey a number of very recent results of existence and uniqueness
of solutions for linearized versions of the SW\, and for the full nonlinea
r SW equations. Although the (linear or nonlinear) SW equations are fully
hyperbolic\, their time independent part can be fully hyperbolic or partly
hyperbolic and partly elliptic. This gives an idea of the complexity of t
he problem and of the diversity of tools which are necessary.\nAll works a
re in collaboration with Aimin Huang .
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20140203T143000
DTEND;TZID=America/New_York:20140203T153000
LOCATION:MB106
URL:http://www.math.psu.edu/seminars/meeting.php?id=19125
SUMMARY:Computational and Applied Mathematics Colloquium - Stability result
s for functional inequalities and applications
DESCRIPTION:Seminar: Computational and Applied Mathematics Colloquium\nTitl
e: Stability results for functional inequalities and applications\nSpeaker
: Alessio Figalli\, University of Texas at Austin\nAbstract Link: http://w
ww.ma.utexas.edu/users/figalli\nAbstract: Geometric and functional inequal
ities play a crucial role in several\nproblems arising in the calculus of
variations\, partial differential\nequations\, geometry\, etc.\nMore recen
tly\, there has been a growing interest in studying the stability\nfor suc
h inequalities.\nThe basic question one wants to address is the following:
suppose we are\ngiven a functional inequality for which minimizers are kn
own. Can we prove\nthat if a function “almost attains the equality” th
en it is close (in some\nsuitable sense) to one of the minimizers?\nThe ai
m of this talk is to describe some ways to attack this kind of\nproblems\,
and to show some applications.\nThe talk is intended to be accessible to
graduate students.
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20140210T143000
DTEND;TZID=America/New_York:20140210T153000
LOCATION:MB106
URL:http://www.math.psu.edu/seminars/meeting.php?id=19126
SUMMARY:Computational and Applied Mathematics Colloquium - Stirring and Mix
ing
DESCRIPTION:Seminar: Computational and Applied Mathematics Colloquium\nTitl
e: Stirring and Mixing\nSpeaker: Gautam Iyer\, Carnegie Mellon University
\nAbstract Link: http://www.math.cmu.edu/math/faculty/iyer.html\nAbstract:
I will talk about various ``mixing'' questions that have attracted\n i
nterest recently. For instance\, ``Can you stir your coffee to keep\n i
t hot for longer''\, or ``How well can you stir cream into your\n coffe
e\, and at what cost?''.\n\n Mathematically these questions translate i
nto studying a negative\n Sobolev norm of a passively advected scalar.
The study of such\n questions also involves very interesting connection
Bressan's (still\n open!) rearrangement cost conjecture. I will spend
most of the talk\n surveying recent results\, and conclude with brief d
escription of\n joint work with A. Kiselev\, Xiaoqian Xu and myself.
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20140217T143000
DTEND;TZID=America/New_York:20140217T153000
LOCATION:MB106
URL:http://www.math.psu.edu/seminars/meeting.php?id=19127
SUMMARY:Computational and Applied Mathematics Colloquium - Diffusion Mapped
Delay Coordinates (DMDC) and the geometry of dynamical data
DESCRIPTION:Seminar: Computational and Applied Mathematics Colloquium\nTitl
e: Diffusion Mapped Delay Coordinates (DMDC) and the geometry of dynamical
data\nSpeaker: Tyrus Berry\, Penn State University\nAbstract: In this tal
k I will examine the geometry of attractor reconstruction and show how the
induced geometry of time-delay coordinates increasingly biases the recons
truction toward the stable directions as delays are added. This bias can b
e exploited\, using the diffusion maps approach to dimension reduction\, t
o extract dynamics on desired time scales from high-dimensional observed d
ata. I discuss the technique of Diffusion Mapped Delay Coordinates (DMDC)
and its application to video data from experiments. Time permitting I wil
l introduce Local Kernels as a generalization of the isotropic kernels use
d in Diffusion Maps which can access geometries other than the induced geo
metry.
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20140224T143000
DTEND;TZID=America/New_York:20140224T153000
LOCATION:MB106
URL:http://www.math.psu.edu/seminars/meeting.php?id=19128
SUMMARY:Computational and Applied Mathematics Colloquium - Finite element m
ethods for incompressible ows with moving interfaces
DESCRIPTION:Seminar: Computational and Applied Mathematics Colloquium\nTitl
e: Finite element methods for incompressible ows with moving interfaces\n
Speaker: Arnold Reusken\, INSTITUT FÜR GEOMETRIE UND PRAKTISCHE MATHEMATI
K\nAbstract Link: http://www.igpm.rwth-aachen.de/personen/reusken\nAbstrac
t: We consider a \now problem with two dierent immiscible incompressible
new-\ntonian phases (\nuid-\nuid or \nuid-gas). A standard model for this
consists of\nthe Navier-Stokes equations with a viscosity and density that
are discontinuous\nacross the interface and with a localized force at the
interface that describes\nsurface tension eects. This \nuid dynamics mod
el can be coupled with a model\nfor mass transport between the phases and
a model for transport of surfac-\ntants on the interface. We discuss why t
he ecient and accurate numerical\nsimulation of such models is a very cha
llenging problem. Two topics\, namely\nthe discretization of the mass tran
sport equation and the discretization of the\nsurfactant equation on the e
volving interface will be treated in more detail.
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20140225T160000
DTEND;TZID=America/New_York:20140225T170000
LOCATION:MB114
URL:http://www.math.psu.edu/seminars/meeting.php?id=22797
SUMMARY:Computational and Applied Mathematics Colloquium - Finite volume me
thods for elasticity and poro-elasticity
DESCRIPTION:Seminar: Computational and Applied Mathematics Colloquium\nTitl
e: Finite volume methods for elasticity and poro-elasticity\nSpeaker: Jan
Martin Nordbotten\, University of Bergen\nAbstract Link: http://folk.uib.n
o/nmajn/index-eng.html\nAbstract: We introduce a new class of cell-centere
d finite volume methods for elasticity and poro-elasticity. This class of
discretization methods has the advantage that the mechanical discretizatio
n is fully compatible (in terms of grid and variables) to the standard cel
l-centered finite volume discretizations that are prevailing for commercia
l simulation of multi-phase flows in porous media. \n\nFor a specific vari
ant of the proposed discretization\, we give an overview of a convergence
proof in the setting of isotropic elasticity\, and address from a theoreti
cal perspective the issues of a discrete Korn's inequality and robustness
with respect to locking. Furthermore\, we give numerical results for both
structured and unstructured grids for both elasticity and poro-elasticity.
The talk concludes with an application to simulation of fractured and fra
cturing porous media.
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20140303T143000
DTEND;TZID=America/New_York:20140303T153000
LOCATION:MB106
URL:http://www.math.psu.edu/seminars/meeting.php?id=19129
SUMMARY:Computational and Applied Mathematics Colloquium - Turbulent fluid
flow and the inviscid limit for the stochastic Navier-Stokes equations
DESCRIPTION:Seminar: Computational and Applied Mathematics Colloquium\nTitl
e: Turbulent fluid flow and the inviscid limit for the stochastic Navier-S
tokes equations\nSpeaker: Vlad Vicol\, Princeton University\nAbstract Link
: http://web.math.princeton.edu/~vvicol/\nAbstract: Turbulence theory aims
to make a precise connection between the ubiquitous complex patterns exhi
bited by fluids at high Reynolds number and the basic equations of fluid d
ynamics\, such as the Navier-Stokes and Euler equations. Given the inheren
t unpredictability of individual realizations in a turbulent regime\, it i
s crucial to develop a statistical approach. This is one of the fundamenta
l motivations for the mathematical study of stochastic partial differentia
l equations in the context of fluids. In particular\, invariant measures p
rovide a canonical object connecting the fluid equations to the heuristic
statistical properties of turbulent flows. In this talk we discuss recent
results concerning the inviscid limit of invariant measures for the 2D sto
chastic Navier-Stokes equations. We prove that the limiting measures are s
upported on bounded vorticity solutions of the 2D Euler equations\, thereb
y answering a question posed by S.~Kuksin. We also discuss connections bet
ween these limiting measures and the statistical mechanics based predictio
ns concerning the long-term dynamics of the 2D Euler equation.
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20140304T160000
DTEND;TZID=America/New_York:20140304T170000
LOCATION:MB114
URL:http://www.math.psu.edu/seminars/meeting.php?id=21700
SUMMARY:Computational and Applied Mathematics Colloquium - Hierarchical int
erpolative factorization
DESCRIPTION:Seminar: Computational and Applied Mathematics Colloquium\nTitl
e: Hierarchical interpolative factorization\nSpeaker: Lexing Ying\, Stanfo
rd University\nAbstract Link: http://math.stanford.edu/~lexing/\nAbstract:
I will discuss some recent results on developing new factorizations\nfor
matrices obtained from discretizing differential and integral\noperators.
A common ingredient of these new factorizations is the\ninterpolative deco
mposition for numerically low-rank matrices. As we\nshall see\, these fact
orizations offer efficient algorithms for\napplying and inverting these op
erators. This is a joint work with\nKenneth Ho.
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20140317T143000
DTEND;TZID=America/New_York:20140317T153000
LOCATION:MB106
URL:http://www.math.psu.edu/seminars/meeting.php?id=19131
SUMMARY:Computational and Applied Mathematics Colloquium - Numerical soluti
on of a poroelasticity problem by stabilized finite element method and mul
tigrid
DESCRIPTION:Seminar: Computational and Applied Mathematics Colloquium\nTitl
e: Numerical solution of a poroelasticity problem by stabilized finite ele
ment method and multigrid\nSpeaker: Carmen Rodrigo\, Universidad de Zarago
za\nAbstract: The classical quasi-static Biot model for soil consolidation
\, describes the time dependent interaction between the deformation of an
elastic porous material and the fluid flow inside of it. This model can be
formulated as a system of partial differential equations for the displace
ment of the solid and the pressure of the fluid. Due to a lack of compati
bility between the boundary and initial conditions\, a transient boundary
layer appears in the pressure field. In such case standard (non stabilize
d) approximation schemes produce non-physical oscillations in the numerica
l solution. Different stabilization strategies have been proposed to overc
ome this. We consider a stabilized linear finite element scheme for the po
roelasticity model\, based on the perturbation of the flow equation. Such
scheme uses low order (piece-wise linear) finite element spaces for both d
isplacements and pressure. The stabilization term results in numerical sol
ution without spurious oscillations\, independently of the discretization
parameters. The resulting linear algebraic system is of saddle point type
and we address its efficient solution by a geometric multigrid method. We
also present local Fourier analysis of the components of the multigrid alg
orithm on simplicial (triangular) grids.
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20140324T143000
DTEND;TZID=America/New_York:20140324T153000
LOCATION:MB106
URL:http://www.math.psu.edu/seminars/meeting.php?id=19132
SUMMARY:Computational and Applied Mathematics Colloquium - Examples of boun
dary layers in fluid mechanics
DESCRIPTION:Seminar: Computational and Applied Mathematics Colloquium\nTitl
e: Examples of boundary layers in fluid mechanics\nSpeaker: Anne-Laure Dal
ibard\, Ecole Normale Superieure de Paris\nAbstract Link: http://www.math.
ens.fr/~dalibard\nAbstract: Boundary layer phenomena occur in various phys
ical contexts (e.g. fluid dynamics\, thermodynamics). A boundary layer mig
ht appear whenever a problem is described by a singular perturbation opera
tor in a bounded domain. If the profile dictated by the singular operator
does not match the conditions on the boundary of the domain\, then the sol
ution must be corrected in the vicinity of the boundary. In this talk\, I
will explain a method which allows to construct boundary layers in a syste
matic way\, under some assumptions on the singular operator. I will also p
resent some examples which do not fit into this framework\, and for which
some kind of "degeneracy" occurs.
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20140331T143000
DTEND;TZID=America/New_York:20140331T153000
LOCATION:MB106
URL:http://www.math.psu.edu/seminars/meeting.php?id=19133
SUMMARY:Computational and Applied Mathematics Colloquium - From PDEs to Inf
ormation Science and Back
DESCRIPTION:Seminar: Computational and Applied Mathematics Colloquium\nTitl
e: From PDEs to Information Science and Back\nSpeaker: Russel Caflisch\, U
niversity of California\, Los Angeles\nAbstract Link: http://www.math.ucla
.edu/~caflisch/\nAbstract: The arrival of massive amounts of data from ima
ging\, sensors\, computation and the internet brought with it significant
challenges for information science. New methods for analysis and manipulat
ion of big data have come from many scientific disciplines. The first focu
s of this presentation is the application of ideas from PDEs\, such as var
iational principles and numerical diffusion\, to image and data analysis.
Examples include denoising\, segmentation\, inpainting and texture extract
ion for images. The second focus is the development of new ideas in inform
ation science\, such as soft-thresholding\, sparsity and compressed sensin
g. The subsequent application of these ideas to PDEs and numerical computa
tion is the third focus of this talk. Examples include soft-thresholding i
n multiscale computation\, solutions with compact support and “compresse
d modes” for PDEs that come from variational principles\, and applicatio
ns to density functional theory.
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20140407T143000
DTEND;TZID=America/New_York:20140407T153000
LOCATION:MB106
URL:http://www.math.psu.edu/seminars/meeting.php?id=19134
SUMMARY:Computational and Applied Mathematics Colloquium - Network formatio
n in Ionomer Membranes
DESCRIPTION:Seminar: Computational and Applied Mathematics Colloquium\nTitl
e: Network formation in Ionomer Membranes\nSpeaker: Keith Promislow\, Mich
igan State University\nAbstract Link: http://www.math.msu.edu/~kpromisl/\n
Abstract: Functionalized polymer membranes have a strong\naffinity for sol
vent\, imbibing it to form charge-lined networks which\nserve as charge-se
lective ion conductions in a host of energy conversion\napplications. We p
resent a continuum model\, based upon a reformulation\nof the Cahn-Hilliar
d free energy\, which incorporates solvation energy and counter-ion\nentro
py to stabilize a host of network morphologies. We derive geometric\nevolu
tion for co-dimension 1 bilayers and co-dimension two pore morphologies\na
nd show that the system possesses a simple mechanism for competitive\nevol
ution of co-existing networks through the common far-field chemical potent
ial.
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20140414T143000
DTEND;TZID=America/New_York:20140414T153000
LOCATION:MB106
URL:http://www.math.psu.edu/seminars/meeting.php?id=19135
SUMMARY:Computational and Applied Mathematics Colloquium - From 0 to High P
erformance Computing in one hour or five ways to do kriging
DESCRIPTION:Seminar: Computational and Applied Mathematics Colloquium\nTitl
e: From 0 to High Performance Computing in one hour or five ways to do kri
ging\nSpeaker: William Brouwer\, RCC Penn State\nAbstract: This presentati
on will give a resource overview of the Research Computing and Cyberinfras
tructure (RCC) unit at PSU\, formerly a unit of ITS\, now transitioning to
the Office of the Vice President for Research. Several consultation examp
les will be given\, encompassing research applications from physics\, chem
ical and electrical engineering. This will be followed by aspects of impor
tant parallel computing models including shared and distributed memory par
allelism\, and general purpose computation using Graphics Processing Units
(GPUs). This seminar will conclude with a hands on portion targeting scie
ntists interested in numerically intensive computing. RCC is a CUDA resear
ch center: https://research.nvidia.com/content/penn-state-crc-summary and
thus GPUs will feature prominently in the seminar overall.
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20140421T143000
DTEND;TZID=America/New_York:20140421T153000
LOCATION:MB106
URL:http://www.math.psu.edu/seminars/meeting.php?id=19121
SUMMARY:Computational and Applied Mathematics Colloquium - TBA
DESCRIPTION:Seminar: Computational and Applied Mathematics Colloquium\nTitl
e: TBA\nSpeaker: Katy Craig\, Rutgers University\nAbstract Link: http://ma
th.rutgers.edu/~katycc/math/katy_craig.html
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20140428T143000
DTEND;TZID=America/New_York:20140428T153000
LOCATION:MB106
URL:http://www.math.psu.edu/seminars/meeting.php?id=19120
SUMMARY:Computational and Applied Mathematics Colloquium - From Crawlers to
Swimmers- Mathematical and Computational Problems in Cell Motility
DESCRIPTION:Seminar: Computational and Applied Mathematics Colloquium\nTitl
e: From Crawlers to Swimmers- Mathematical and Computational Problems in C
ell Motility\nSpeaker: Hans G Othmer\, University of Minnesota\nAbstract L
ink: http://www.math.umn.edu/~othmer/\nAbstract: Cell locomotion is essent
ial for early development\,\n angiogenesis\, tissue regeneration\, the i
mmune response\, and\n wound healing in multicellular organisms\, and pl
ays a very\n deleterious role in cancer metastasis in humans. Locomotion
\n involves the detection and transduction of extracellular\n chemical
and mechanical signals\, integration of the signals\n into an intracell
ular signal\, and the spatio-temporal control\n of the intracellular bio
chemical and mechanical responses that\n lead to force generation\, morp
hological changes and directed\n movement. While many single-celled org
anisms use flagella or\n cilia to swim\, there are two basic modes of mo
vement used by\n eukaryotic cells that lack such structures -- mesenchym
al and\n amoeboid. The former\, which can be characterized as `crawling
'\n in fibroblasts or `gliding' in keratocytes\, involves the\n extens
ion of finger-like filopodia or pseudopodia and/or broad\n flat lamellip
odia\, whose protrusion is driven by actin\n polymerization at the leadi
ng edge. This mode dominates in\n cells such as fibroblasts when moving
on a 2D substrate. In the\n amoeboid mode\, which does not rely on stro
ng adhesion\, cells\n are more rounded and employ shape changes to move
-- in effect\n 'jostling through the crowd' or `swimming'. Here force\n
generation relies more heavily on actin bundles and on the\n control
of myosin contractility. Leukocytes use this mode for\n movement throug
h the extracellular matrix in the absence of\n adhesion sites\, as does
Dictyostelium discoideum when\n cells sort in the slug. However\, recent
experiments have shown\n that numerous cell types display enormous plas
ticity in\n locomotion in that they sense the mechanical properties of\n
their environment and adjust the balance between the modes\n accordin
gly by altering the balance between parallel signal\n transduction pathw
ays. Thus pure crawling and pure swimming\n are the extremes on a conti
nuum of locomotion strategies\, but\n many cells can sense their environ
ment and use the most\n efficient strategy in a given context. We will d
iscuss some of\n the mathematical and computational challenges that this
\n diversity poses.
END:VEVENT
END:VCALENDAR