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
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END:VTIMEZONE
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20150824T143000
DTEND;TZID=America/New_York:20150824T153000
LOCATION:MB106
URL:http://www.math.psu.edu/seminars/meeting.php?id=27301
SUMMARY:Computational and Applied Mathematics Colloquium - Global Riemann S
olver for Gas Flooding in Reservoir Simulation
DESCRIPTION:Seminar: Computational and Applied Mathematics Colloquium\nTitl
e: Global Riemann Solver for Gas Flooding in Reservoir Simulation\nSpeaker
: Wen Shen\, Penn State\nAbstract: In this talk we consider the model for
gas flooding with three component. The resulting model is a 2 × 2 system
of conservation law. The model is known to be non-hyperbolic\, with variou
s degeneracies. These include a curve and an area of linearly degeneracy\,
two curves of parabolic degeneracy. We present a construction of the glob
al Riemann Solver\, which takes advantage of the under- lining splitting p
roperty of the thermo-dynamics from the hydro-dymanics. This is a joint wo
rk with S. Khorsandi and R. Johns\, both from Department of Energy and Min
eral Engineering\, Penn State University.
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20150831T143000
DTEND;TZID=America/New_York:20150831T153000
LOCATION:MB106
URL:http://www.math.psu.edu/seminars/meeting.php?id=27303
SUMMARY:Computational and Applied Mathematics Colloquium - Effective decoup
ling for general purpose reservoir simulation
DESCRIPTION:Seminar: Computational and Applied Mathematics Colloquium\nTitl
e: Effective decoupling for general purpose reservoir simulation\nSpeaker:
Changhe Qiao\, Penn State\nAbstract: Reservoir simulation is one of the m
ost important tools for reservoir engineers to estimate\, predict and opti
mize the petroleum oil and gas production. By describing the dynamics of m
ultiphase flow in subsurface\, the evolution of production rate\, undergro
und pressure and optimal well placement can be accurately predicted based
on accurate geological data. The Black oil model and the compositional mod
el are two of the most popular models in the past few decades. This paper
aims to design the optimal decoupling and preconditioning technology for g
eneral purpose reservoir simulation.\nBased on a compositional formulation
\, the Jacobian matrix was analyzed based on the differential operators. T
he existing decoupling techniques were analyzed and convergence was shown
when the time step size approaches zero. An analytical decoupling techniqu
e at the partial differential equation level was proposed. Based on the an
alysis\, a new decoupling method\, which combined the analytical and algeb
raic methods\, was proposed. Numerical experiments demonstrated the benefi
t of the new decoupling method.
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20150907T143000
DTEND;TZID=America/New_York:20150907T153000
LOCATION:MB106
URL:http://www.math.psu.edu/seminars/meeting.php?id=27305
SUMMARY:Computational and Applied Mathematics Colloquium - TBA
DESCRIPTION:Seminar: Computational and Applied Mathematics Colloquium\nTitl
e: TBA
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20150914T143000
DTEND;TZID=America/New_York:20150914T153000
LOCATION:MB106
URL:http://www.math.psu.edu/seminars/meeting.php?id=27307
SUMMARY:Computational and Applied Mathematics Colloquium - Hollow Vortices
DESCRIPTION:Seminar: Computational and Applied Mathematics Colloquium\nTitl
e: Hollow Vortices\nSpeaker: Stefan Llewellyn Smith (Host: Andrew)\, Depar
tment of Mechanical and Aerospace Engineering\, UCSD\nAbstract: Hollow vor
tices are vortices whose interior is at rest. They posses vortex sheets o
n their boundaries and can be viewed as a desingularization of point vorti
ces. After giving a history of point vortices\, we obtain exact solutions
for hollow vortices in linear and nonlinear strain and examine the propert
ies of streets of hollow vortices. The former can be viewed as a canonica
l example of a hollow vortex in an arbitrary flow\, and its stability prop
erties depend on a single non-dimensional parameter. In the latter case\,
we reexamine the hollow vortex street of Baker\, Saffman and Sheffield an
d examine its stability to arbitrary disturbances\, and then investigate t
he double hollow vortex street. Implications and extensions of this work a
re discussed.
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20150921T143000
DTEND;TZID=America/New_York:20150921T153000
LOCATION:MB106
URL:http://www.math.psu.edu/seminars/meeting.php?id=27309
SUMMARY:Computational and Applied Mathematics Colloquium - The Fokker-Planc
k equation in bounded domains
DESCRIPTION:Seminar: Computational and Applied Mathematics Colloquium\nTitl
e: The Fokker-Planck equation in bounded domains\nSpeaker: Hyung ju Hwang
\, Postech\, Korea and Brown University\nAbstract: In this talk\, we consi
der the initial-boundary value problem for the Fokker-Planck equation in a
n interval or in a bounded domain with absorbing boundary conditions. We d
iscuss a theory of well-posedness of classical solutions for the problem a
s well as the exponential decay in time\, hypoellipticity away from the si
ngular set\, and the Holder continuity of the solutions up to the singular
set. This is a joint work with J. Jang\, J. Jung\, and J. Velazquez.
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20150928T143000
DTEND;TZID=America/New_York:20150928T153000
LOCATION:MB106
URL:http://www.math.psu.edu/seminars/meeting.php?id=27311
SUMMARY:Computational and Applied Mathematics Colloquium - A Hamilton-Jacob
i formalism to large deviation and related problems
DESCRIPTION:Seminar: Computational and Applied Mathematics Colloquium\nTitl
e: A Hamilton-Jacobi formalism to large deviation and related problems\nSp
eaker: Jin Feng (Host: Chun)\, University of Kansas\nAbstract: I plan to u
se this talk to provide a user's guide for a method described in the book
"Large deviations for stochastic processes" by Feng and Kurtz 2006. This i
s a Hamilton-Jacobi approach to the theory of large deviation for metric s
pace valued Markov processes.\n\nIn the first part\, I explain some basic
observations that lead to such a formulation. Then I will describe the who
le scheme and mathematical challenges associated with applications of the
theory to concrete examples.\n\nIn the second part\, I show one non-equili
brium statistical mechanics example of a mean-field type\, and one recent
example studied in Gibbs-Non-Gibbs transitions. I use this opportunity to
motivate the relevance of studying a class of Hamilton-Jacobi equations in
space of probability measures. Time permitting\, I present some ideas for
proving comparison principle (i.e. uniqueness) for such equations.
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20151005T143000
DTEND;TZID=America/New_York:20151005T153000
LOCATION:MB106
URL:http://www.math.psu.edu/seminars/meeting.php?id=27313
SUMMARY:Computational and Applied Mathematics Colloquium - Stability of Ens
emble Kalman Filters
DESCRIPTION:Seminar: Computational and Applied Mathematics Colloquium\nTitl
e: Stability of Ensemble Kalman Filters\nSpeaker: Xin Tong\, Courant Insti
tute\nAbstract: The ensemble Kalman filters are data assimilation methods
for high dimensional\, nonlinear dynamical models. Despite their widesprea
d usage\, very little is known about their long-time dynamical behavior. I
n this talk\, we discuss the criterions that guarantee the filter ensemble
to be time uniformly bounded and geometrically ergodic. Contradiction to
these criterions may lead to catastrophic filter divergence\, which can be
demonstrated by a simple example. Finally\, we show that a simple adapti
ve covariance inflation scheme can guarantee filter stability.
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20151012T143000
DTEND;TZID=America/New_York:20151012T153000
LOCATION:MB106
URL:http://www.math.psu.edu/seminars/meeting.php?id=27315
SUMMARY:Computational and Applied Mathematics Colloquium - From a priori er
ror estimates to a posteriori error estimates for the finite element appro
ximations of boundary value problems with singularities
DESCRIPTION:Seminar: Computational and Applied Mathematics Colloquium\nTitl
e: From a priori error estimates to a posteriori error estimates for the f
inite element approximations of boundary value problems with singularities
\nSpeaker: Serge Nicaise (Host: A Mazzucato)
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20151019T143000
DTEND;TZID=America/New_York:20151019T153000
LOCATION:MB106
URL:http://www.math.psu.edu/seminars/meeting.php?id=27317
SUMMARY:Computational and Applied Mathematics Colloquium - Energy driven pa
ttern formation in thin fluid layers: The good\, the bad and the beautiful
DESCRIPTION:Seminar: Computational and Applied Mathematics Colloquium\nTitl
e: Energy driven pattern formation in thin fluid layers: The good\, the ba
d and the beautiful\nSpeaker: Andrew Bernoff (Host: A Belmonte)\, Harvey M
udd College\nAbstract: A wide variety of physical and biological systems c
an be described as continuum limits of interacting particles. Their dynami
cs can often be described in terms of a monotonically decreasing interacti
on energy. We show how to exploit these energies numerically\, analyticall
y and asymptotically to characterize the observed behavior. Examples are d
rawn from the dynamics of thin fluid layers including ferrofluids.
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20151026T122000
DTEND;TZID=America/New_York:20151026T133000
LOCATION:MB114
URL:http://www.math.psu.edu/seminars/meeting.php?id=27318
SUMMARY:Computational and Applied Mathematics Colloquium - Preconditioners
for dense matrices using hierarchical matrices
DESCRIPTION:Seminar: Computational and Applied Mathematics Colloquium\nTitl
e: Preconditioners for dense matrices using hierarchical matrices\nSpeaker
: Eric Darve\, Stanford University\nAbstract: Building preconditioners for
iterative methods is a critical part of building an efficient linear solv
er. However\, general methods to do so are still lacking and many precondi
tioners remain problem specific. We will present a new class of preconditi
oners based on direct factorization of hierarchical matrices (e.g.\, fast
multipole method). These preconditioners have a computational cost in O(N)
\, with a tunable accuracy. They rely on algebraic manipulations and do no
t require insight into the underlying partial differential equation. We wi
ll discuss connections with incomplete Cholesky\, and algebraic multigrid.
Benchmarks will be presented with mesh deformation applications.
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20151026T143000
DTEND;TZID=America/New_York:20151026T153000
LOCATION:MB106
URL:http://www.math.psu.edu/seminars/meeting.php?id=27319
SUMMARY:Computational and Applied Mathematics Colloquium - Modeling 3D Ion
and Electron Transport in Li-Ion Battery and Enhancing Sparsity in High-Di
mensional Uncertainty Quantification
DESCRIPTION:Seminar: Computational and Applied Mathematics Colloquium\nTitl
e: Modeling 3D Ion and Electron Transport in Li-Ion Battery and Enhancing
Sparsity in High-Dimensional Uncertainty Quantification\nSpeaker: Guang Li
n\, Purdue University (Host: C Liu)\nAbstract: In the first part of the ta
lk\, I will present an efficient numerical algorithms for solving 3D stead
y-state Poisson-Nernst-Planck (PNP) equations with excess chemical potenti
als described by the classical density functional theory. Numerical result
s for ion and electron transport in solid electrolyte for lithium-ion batt
eries are shown to be in good agreement with the experimental data. In the
second part of the talk\, I will present our recent work in employing com
pressive sensing for high-dimensional uncertainty quantification. To enhan
ce sparsity in high-dimensional Hermite polynomial expansions\, we conside
r data-driven rotation-based linear mapping strategies to identify new bas
es for random variables\, and greatly improve the efficiency and accuracy
of the compressive sensing-based uncertainty quantification method. We dem
onstrate the effectiveness of the new method with applications in solving
stochastic partial differential equations and high-dimensional O(10^2) pro
blems.
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20151102T143000
DTEND;TZID=America/New_York:20151102T153000
LOCATION:MB106
URL:http://www.math.psu.edu/seminars/meeting.php?id=27321
SUMMARY:Computational and Applied Mathematics Colloquium - Parallel Multile
vel Algorithms for Fluid-Structure Interaction Problems with Applications
in Blood Flow Simulations
DESCRIPTION:Seminar: Computational and Applied Mathematics Colloquium\nTitl
e: Parallel Multilevel Algorithms for Fluid-Structure Interaction Problems
with Applications in Blood Flow Simulations\nSpeaker: Xiao-Chuan Cai\, De
partment of Computer Science\, University of Colorado Boulder\nAbstract: F
luid-structure interaction is a challenging multi-physics problem. In this
talk we discuss a parallel domain decomposition based framework for solvi
ng the implicitly discretized\, monolithically coupled system consisting o
f the Navier-Stokes equations for the fluid and the elasticity equation fo
r the solid. The algorithm involves an inexact Newton-Krylov algorithm wit
h a multilevel overlapping Schwarz preconditioner. We apply the algorithm
to a blood flow problem in 3D compliant arteries. We show that the propose
d algorithm is robust with respect to the physical parameters and scalable
in terms of the iteration count and the total compute time on a supercomp
uter with a large number of processors.
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20151109T143000
DTEND;TZID=America/New_York:20151109T153000
LOCATION:MB106
URL:http://www.math.psu.edu/seminars/meeting.php?id=27323
SUMMARY:Computational and Applied Mathematics Colloquium - Mathematical mod
els and numerical simulations of oil recovery
DESCRIPTION:Seminar: Computational and Applied Mathematics Colloquium\nTitl
e: Mathematical models and numerical simulations of oil recovery\nSpeaker:
Thormod Johansen
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20151113T143000
DTEND;TZID=America/New_York:20151113T153000
LOCATION:MB106
URL:http://www.math.psu.edu/seminars/meeting.php?id=30088
SUMMARY:Computational and Applied Mathematics Colloquium - Stability of the
Couette flow
DESCRIPTION:Seminar: Computational and Applied Mathematics Colloquium\nTitl
e: Stability of the Couette flow\nSpeaker: Pierre Germain\, Courant\, NYU
\nAbstract Link: http://www.cims.nyu.edu/~pgermain/indexenglish.html\nAbst
ract: The Couette flow is well-known to be linearly stable (for positive\n
viscosity)\, but often experimentally unstable. It was proposed by Lord\nK
elvin that this is due to the basin of attraction shrinking very rapidly\n
as the viscosity goes to zero. I will present analytical results\nestimati
ng the size of the basin of attraction in different topologies (ie\nfor mo
re or less regular perturbations). These analytical results give a\nvery c
lose agreement with recent numerical experiments\, which indicates\nthey s
hould be optimal. This is joint work with Jacob Bedrossian and Nader\nMasm
oudi
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20151116T143000
DTEND;TZID=America/New_York:20151116T153000
LOCATION:MB106
URL:http://www.math.psu.edu/seminars/meeting.php?id=27325
SUMMARY:Computational and Applied Mathematics Colloquium - On the homogeniz
ation of a transmission problem in scattering theory for highly oscillatin
g media
DESCRIPTION:Seminar: Computational and Applied Mathematics Colloquium\nTitl
e: On the homogenization of a transmission problem in scattering theory fo
r highly oscillating media\nSpeaker: Shari Moskow (Host: Anna)\, Drexel\nA
bstract: Here we study homogenization of a transmission problem for bounde
d scatterers\nwith periodic coecients modeled by the anisotropic Helmholtz
equation. The material property\ncoecients are assumed to be periodic fun
ctions over the unit cell for the fast variable. By way\nof multiple scale
s expansion\, we focus on the O(k)\, k = 1\; 2 bulk and boundary correctio
ns of\nthe leading-order (O(1)) homogenized transmission problem. The anal
ysis in particular provides\nthe H1 and L2 estimates of the error committe
d by the first-order-corrected solution considering i)\nbulk correction on
ly\, and ii) boundary and bulk correction. We treat explicitly the O(\\eps
ilon ) boundary\ncorrection for the transmission problem when the scattere
r is a unit square. We also establish the\nO(\\epsilon^2)-bulk correction
describing the mean wave motion inside the scatterer. The analysis here al
so\nhighlights a previously established\, yet scarcely recognized fact tha
t the O(\\epsilon ) bulk correction of the\nmean motion vanishes identical
ly.
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20151123T143000
DTEND;TZID=America/New_York:20151123T153000
LOCATION:MB106
URL:http://www.math.psu.edu/seminars/meeting.php?id=27327
SUMMARY:Computational and Applied Mathematics Colloquium - TBA
DESCRIPTION:Seminar: Computational and Applied Mathematics Colloquium\nTitl
e: TBA\nSpeaker: Thanksgiving
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20151130T143000
DTEND;TZID=America/New_York:20151130T153000
LOCATION:MB106
URL:http://www.math.psu.edu/seminars/meeting.php?id=27329
SUMMARY:Computational and Applied Mathematics Colloquium - An analysis of i
mplicit sampling in the small-noise limit
DESCRIPTION:Seminar: Computational and Applied Mathematics Colloquium\nTitl
e: An analysis of implicit sampling in the small-noise limit\nSpeaker: Kev
in Lin\nAbstract: Weighted direct samplers\, also known as importance samp
lers\,\nare Monte Carlo algorithms for generating independent\,\nweighted
samples from a given target probability\ndistribution. Such algorithms ha
ve a variety of\napplications in\, e.g.\, data assimilation and state\nest
imation problems involving stochastic and chaotic\ndynamics. One challeng
e in designing and implementing\nweighted samplers is to ensure the varian
ce of the weights\,\nand that of the resulting estimator\, are well-behave
d. In\nrecent work\, Chorin\, Tu\, Morzfeld\, and coworkers have\nintrodu
ced a class of novel weighted samplers called implicit\nsamplers\, which h
ave been shown to possess a number of nice\nproperties. In this talk\, I
will report on an analysis of\nthe variance of implicit samplers in the sm
all-noise limit\,\nand describe a simple method (suggested by the analysis
) to\nobtain higher-order implicit samplers. The algorithms are\ncompared
concrete test problems. This is joint work with\nJonathan Goodman and Ma
tthias Morzfeld.
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20151207T143000
DTEND;TZID=America/New_York:20151207T153000
LOCATION:MB106
URL:http://www.math.psu.edu/seminars/meeting.php?id=27331
SUMMARY:Computational and Applied Mathematics Colloquium - TBA
DESCRIPTION:Seminar: Computational and Applied Mathematics Colloquium\nTitl
e: TBA\nSpeaker: Richard Liu (Michigan State University) Host: Xiantao
END:VEVENT
END:VCALENDAR