This is an introduction to the lectures and the tutorials. We will study different topics, differential geometric topic using analysis for the lectures and topological topics with numerical experiments for the tutorials. A survey for the knot energies will also be given.
Creator:
O'Hara, Jun (Chiba University)
Created:
2019-06-17
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
Tuhin Sahai: Dynamical Systems and Continous Approximations for NP-hard Problems In this talk, we will explore the use of dynamical systems for approximating the solutions of NP-hard problems that arise in a wide variety of Industrial settings. In particular, we will investigate the use of dynamical systems for clustering networks and performing...
Creator:
Sahai, Tuhin (United Technologies Corporation); Swaminathan, Sumanth (W. L. Gore & Associates)
Created:
2015-04-20
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
Viktoria Averina: Algorithm Development for Medical DevicesImplantable cardiac devices such as pacemakers and defibrillators can track and analyze patient's physiological data. I will showcase key steps of research and development of device-based respiratory monitoring: how one measures patient's respiratory function, why one would want to track...
Creator:
Averina, Viktoria A. (Boston Scientific); Sachs, Jeff (Merck & Co., Inc.)
Created:
2015-04-21
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
What new things can we make from 2D Materials? The possibilities are incredibly varied, from novel quantum systems to functional nanoscale machines. In this talk, I'll discuss three things we've built: a tunable 2D exciton, a thermal guitar, and a new class of self-folding origami devices.
Creator:
McEuen, Paul (Cornell University)
Created:
2017-05-17
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
We begin with the generalization of electrostatic energy of charged knots, where we come across the difficulty of divergent integrals. Two kinds of regularization will be introduced, Hadamard regularization and the regularization via analytic continuation, both from the theory of generalized functions.
Creator:
O'Hara, Jun (Chiba University)
Created:
2019-06-18
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
Given a near-perfect X-ray source, such as a synchrotron, then what are the reasonable options for image reconstruction? Back-projection reconstruction has dominated, with lambda tomography not receiving the attention it deserves. Give the computation power a the beamline, is it reasonable to perform both reconstructions so as to discern object ...
Creator:
Butler, Les G. (Louisiana State University)
Created:
2006-01-12
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
I shall talk about building 3D models from image sequences, and inparticular about rendering new views of existing sequences in orderto create stereoscopic 3D from monocular footage. I shall show howexisting strategies for image-based rendering can be augmented usingimage-based priors to create realistic 3D views. In addition I willtalk about th...
Creator:
Fitzgibbon, Andrew (Microsoft Research)
Created:
2006-02-07
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
3D optical elements modulate light through interaction with an entirevolume of variable refractive index (as opposed to a sequence of surfacesused in traditional optics.) One commonly used form of 3D optics isgradient-index (GRIN) where the modulation is base-band. Instead, we haveemphasized use of modulations on a spatial carrier (grating.) We ...
Creator:
Barbastathis, George (Massachusetts Institute of Technology)
Created:
2005-11-11
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
In this talk I will describe recent results in the segmentationof relevant structures in electron tomography.We have developed novel techniques based onPDEs to work with this extremely hard data.I will describe the problem and the proposed solution,both at a tutorial level for a general audience.This is joint work with A. Bartesaghi and S. Subra...
Creator:
Sapiro, Guillermo R. (University of Minnesota, Twin Cities)
Created:
2006-01-11
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
We will see that Hadamard regularization and the regularization via analytic continuation give essentially the same information. This part is rather technical, although it will save complicated computation afterward.
Creator:
O'Hara, Jun (Chiba University)
Created:
2019-06-20
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
We apply the regularization via analytic continuation to generalized Riesz energies of submanifolds in Euclidean spaces to obtain Brylinski's beta function, which is a meromorphic function with simple poles. We study geometric information that can be derived from Brylinski's beta function.
Creator:
O'Hara, Jun (Chiba University)
Created:
2019-06-21
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
Carbonara, Joaquin (Buffalo State - SUNY); Spirn, Daniel (University of Minnesota, Twin Cities); Symes, William W. (Rice University); Vernescu, Bogdan M. (Worcester Polytechnic Institute)
Created:
2014-04-08
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
Hilbert bases, Graver bases and toric Gröbner bases are at the heart of many problems arising in mathematics or in practice. In this talk we present the main functionality and the algorithmic theory behind the software package 4ti2. Furthermore, we present applications (theoretical and computational) from various mathematical fields such as tori...
Creator:
Hemmecke, Raymond (Otto-von-Guericke-Universität Magdeburg)
Created:
2006-10-25
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
A method to construct M\"obius invariant weighted inner products on the tangent spaces of the knot space by using M\"obius invariant knot energies will be introduced. It gives M\"obius invariant gradients of such energies."
Creator:
O'Hara, Jun (Chiba University)
Created:
2019-06-25
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
This talk will describe a new approach for optimizing dynamic treatment regimes that bridges the gap between Bayesian inference and Q-learning. The proposed approach fits a series of Bayesian regression models, one for each stage, in reverse sequential order. Each model regresses the remaining payoff assuming optimal actions are taken at subsequ...
Creator:
Murray, Thomas (University of Minnesota, Twin Cities)
Created:
2018-11-07
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
The human world is full of things that move: people travelling, inbuses and trains and cars and taxis, goods being shipped anddelivered, etc. etc. Sensors for recording these movements arebecoming cheaper and more widespread, from GPS-equipped mobile phonesto smart commuter cards, and so there is an explosion in the amount ofmovement data that i...
Creator:
Wischik, Damon (Urban Engines)
Created:
2015-10-20
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
In an ab initio molecular dynamics calculation, the finite-temperature dynamics of a system is generated using forces obtained directly from electronic structure calculations performed 'on the fly' as the simulation proceeds. Within this approach, manybody forces, electronic polarization, and chemical bond-breaking and forming evnets are treated...
Creator:
Tuckerman, Mark E. (New York University)
Created:
2008-12-07
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
In this tutorial, we will show how to incorporate nuclear quantum effects into an ab initio molecular dynamics calculation via the Feynman path-integral formulation of quantum statistical mechanics. Important algorithmic advances needed to accelerate the convergence of the calculations will be discussed as well as approximation dynamical path-in...
Creator:
Tuckerman, Mark E. (New York University)
Created:
2008-12-07
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
Ablative Rayleigh-Taylor (R-T) instability is a special feature of the acceleration phase in inertial confinement fusion (ICF). Ablation stabilizes the disturbances with small wavelength, introducing a marginal wavelength. Due to a large temperature ratio, the conduction length-scale varies strongly across the wave, and the attention is limited ...
Creator:
Clavin, Paul (UMR CNRS-Universites d'Aix-Marseille I&II)
Created:
2008-07-15
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
Joint work with I Vitebskiy.Wave propagation in spatially periodic media, such as photonic crystals, can be qualitatively differentfrom any uniform substance. The differences are particularly pronounced when the electromagnetic wavelengthis comparable to the minimal translation of the periodic structure. In such a case, the periodic medium canno...
Creator:
Figotin, Alexander (University of California, Irvine)
Created:
2006-10-04
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
Joint work with Ahmet Ay2, Evan Dayringer2, Rupinder Sayal1, Chichia Chiu2, David N. Arnosti1.Cis regulatory information comprises a key portion of genetic coding,yet despite the abundance of genomic sequences now available,identifying and characterizing this information remains a majorchallenge. We are pursuing a unique "bottom-up" approach to ...
Creator:
Fakhouri, Walid (Michigan State University)
Created:
2008-03-04
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
Joint work with Sven Leyffer (Argonne National Laboratory)and Emilie Wanufelle (University of Namur).Motivated by problems related to power systems analysis which give riseto nonconvex mixed integer nonlinear programming (MINLP) problems,we propose a global optimization method based on ideas and techniquesthat can be easily extended to handle a ...
Creator:
Sartenaer, Annick (Facultés Universitaires Notre Dame de la Paix (Namur))
Created:
2008-11-18
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
In these two lectures, I will give a introduction to a few dissipative stochastic partial differential equations including existence and uniqueness of solutions. I try to emphasis what is different phenomenologically between SODEs (Stochastic Ordinary Differential Equations) and SPDEs (Stochastic Partial Differential Equations) when viewed as st...
Creator:
Mattingly, Jonathan C.
Created:
2013-01-11
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
The talk will briefly recall the basic features of Virtual Element Spaces, with different types of conformity: H1, H(div), H(curl), etc., together with their Serendipity variants. Special constructions (for incompressible fluids or for Hellinger-Reissner formulations of Elasticity) will also be mentioned, together with some hints on the actual a...
Creator:
Brezzi, Franco (Istituto di Matematica Applicata e Tecnologie Informatiche)
Created:
2017-06-30
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
Functions and theirepigraphs, convexity and semicontinuity.Set convergence and epigraphical limits. Variational geometry,subgradientsand subdifferential calculus.
Creator:
Wets, Roger J.B. (University of California, Davis)
Created:
2010-10-16
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
We study a Helmholtz-type spectral problem in a two-dimensional medium consisting of a fully periodic background structure and a perturbation in form of a line defect. The defect is aligned along one of the coordinate axes, periodic in that direction (with the same periodicity as the background), and bounded in the other direction. This setting ...
Creator:
Radosz, Maria (Rice University)
Created:
2016-12-13
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
In this talk I shall discuss some recent progresses in developing interior penalty discontinuous Galerkin (IPDG) methods and local discontinuous Galerkin (LDG) methods for high frequency scalar wave equation.The focus of the talk is to present some non-standard (h- and hp-) IPDG and LDG methods which are proved to be absolutely stable (with resp...
Creator:
Feng, Xiaobing Henry (University of Tennessee)
Created:
2010-11-02
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
In this talk we describe a mathematical model which couples the educationand labor markets, in which steady-steady competitive equilibria turn out to be characterized as the solutions to an infinite-dimensional linear program and its dual. In joint work with Erlinger, Shi, Siow and Wolthoff, we use ideas from optimal transport, to analyze this p...
Creator:
McCann, Robert (University of Toronto)
Created:
2015-04-28
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
We consider a Cahn-Hilliard functional with long-range interactions. This functional was introduced as a qualitative way of modeling self-assembly of diblock copolymers. We will consider the phase diagram from the point of view of numerical simulations. We will also describe analytical work, via Gamma convergence, on the asymptotics of the energ...
Creator:
Choksi, Rustum (Simon Fraser University)
Created:
2009-03-25
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
We survey rigorous, formal, and numerical results on the formation ofpoint-like singularities (or blow-up) for a wide range of evolutionequations. We use a similarity transformation of the original equation withrespect to the blow-up point, such that self-similar behaviour is mapped tothe fixed point of an infinite dimensional dynamical system. ...
Creator:
Eggers, Jens (University of Bristol)
Created:
2008-07-14
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
A long literature has illustrated the potentially severe consequences of subversion of feedback control within electric power grids, well before Stuxnet brought wide attention to the threat of industrial control system cyber-attacks. The electromechanical dynamics of the power system make it uniquely vulnerable. Power grids typically possess lig...
Creator:
DeMarco, Christopher L. (University of Wisconsin, Madison)
Created:
2016-05-10
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
In this talk we present two intimately related approaches in speeding-up molecular simulations via Monte Carlo simulations.First, we discuss coarse-graining algorithms for systems with complex, and often competing particle interactions, both in the equilibrium and non-equilibrium settings, which rely on multilevelsampling and communication. Seco...
Creator:
Katsoulakis, Markos A. (University of Massachusetts)
Created:
2010-10-22
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
PhotoAcoustic Tomography (PAT) has become established as a significant imaging modality allowing the qualitative imaging in 3D of absorbed optical energy in the visible and near-infrared range, with high resolution, by exploiting the conversion of optical to acoustic energy and the discontinuity preserving propagation of ultrasound under the ass...
Creator:
Arridge, Simon (University College London)
Created:
2019-04-29
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
The current trends in processor architecture design are driven by the end of so called era of Dennard scaling in around 2005. Thermal power dissipation issues associated with increasing processor clock frequency has instead led to processors being designed with many compute cores equipped with ever more numerous and wider vector units. The adven...
Creator:
Warburton, Timothy C. (Rice University)
Created:
2014-10-15
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
In this survey talk, I collect a lot of results from discrete and computational geometry, explaining the special role that 'touchings' (tangencies) play in te subject. These questions contributed to the early development of the theory of Davenport-Schinzel sequences, algorithmic motion planning, geometric graph theory, and incidence geometry. We...
Creator:
Pach, Jà¡nos (École Polytechnique Fédérale de Lausanne (EPFL))
Created:
2014-11-11
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
The crocodilia have multiple interesting characteristics thataffect their population dynamics. They are among severalreptile species which exhibit temperature-dependent sexdetermination (TSD) in which the temperature of eggincubation determines the sex of the hatchlings. Their lifeparameters, specifically birth and death rates, exhibitstrong age...
Creator:
Gallegos, Angela C. (Occidental College)
Created:
2009-04-03
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
In this talk we propose a probabilistic interpretation of the parameters in the system of differential equations describing a complex cellular brain metabolism model. Uncertainty in the parameter values, variability of the data over a population and errors in the collected data contribute to the variance of the distributions of the parameters. M...
Creator:
Calvetti, Daniela (Case Western Reserve University)
Created:
2010-10-20
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
The accumulation of photon impacts on a surface is the essence of photography. We will investigate the use of acumulation for both image and video fusion/restoration. Registration and patch based methods will be compared for several applications.
Creator:
Buades, Antoni (Université de Paris V (René Descartes))
Created:
2011-03-11
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
We consider a noisy observerfor an unknown solution u(t) of a deterministic model.The observer is a stochastic model similar to the original one,and it arises as a limit of frequent observations in filtering.Here noisy observations of the low Fourier modes of u(t)together with knowledge of the deterministic model are used to trackthe unknown sol...
Creator:
Blömker, Dirk (Universität Augsburg)
Created:
2012-10-24
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
Model order reduction is a pervasive and necessary activity in materials research. However, even though reduced order models are never perfect, their "imperfection" is almost never accounted for. In this talk, I will give an example of how the quality of an inference in materials research may be improved by accounting for the imperfection of a r...
Creator:
Demkowicz, Michael J (Massachusetts Institute of Technology)
Created:
2013-12-17
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
Nanofiltration (NF) using membranes with numerous nanopores has gained its popularity in water treatment like desalination. Overlapped electric double layer (EDL) in charged nanopores makes the membrane to be ion selective and reach high rejection rate for salts when driving electrolyte through nanopores by pressure. It has its advantage over re...
Creator:
Horng, Tzyy-Leng (Feng Chia University)
Created:
2015-07-22
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
Symbioses of grasses and fungal endophytes constitute aninteresting modelfor evolution of mutualism and parasitism. Grasses of allsubfamilies canharbor systemic infections by fungi of the familyClavicipitaceae. SubfamilyPoöideae is specifically associated with epichloëendophytes (speciesof Epichloë and their asexual derivatives, the Neotyphodi...
Creator:
Yoshida, Ruriko (University of Kentucky)
Created:
2007-03-09
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
Joint work with Michael Armbruster (TU Chemnitz), Marzena Fuegenschuh (TU Darmstadt), and Alexander Martin (TU Darmstadt).Semidefinite relaxations are known to deliver good approximationsfor combinatorial optimization problems like graph bisection. Usingthe spectral bundle method it is possible to exploit structuralproperties of the underlying p...
Creator:
Helmberg, Christoph (Technische Universität Chemnitz-Zwickau)
Created:
2008-11-19
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
We present a general comparison inequality between positively associated and independently distributed random variables, generalizing the Gaussian comparison inequality. The proof uses several combinatorial identities and the property of positive association. We also provide applications where the maxima of correlated r.v.s behaves in the same w...
Creator:
Dey, Partha Sarathi (University of Illinois at Urbana-Champaign)
Created:
2015-04-29
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
After a brief overview of electrohydrodynamics including Maxwell's electric stress tensor under AC fields where the medium has both conductive and dielectric characteristics, we focus on the problem of electrowetting actuation of sessile drops on a patterned array of electrodes with a thin dielectric coating. For both the case when the drop is e...
Creator:
Nadim, Ali (Claremont Graduate University)
Created:
2009-03-24
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
A prominent concern, in the age of machine learning and data analysis, is that left to their own devices, algorithms will propagate - even amplify - existing biases. Common definitions of fairness are group-based, typically requiring that a given statistic be equal across a few demographic groups, socially identified as deserving protection. Suc...
Creator:
Reingold, Omer (Stanford University)
Created:
2019-06-19
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
Kinetochores are nano-structures that mechanically couple chromosomesto dynamic microtubules to generate the forces necessary for properchromosome segregation during mitosis. Recent studies reveal newdetails of the kinetochore's molecular composition and structure,demonstrating the mechanically compliant nature of the kinetochorelinkage to the m...
Creator:
Odde, David J. (University of Minnesota, Twin Cities)
Created:
2013-05-16
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
This talk will discuss a substantial interplay of algebraic topology with numerical analysis which has developed over the last decade. During this period, de Rham cohomology and the Hodge theory of Riemannian manifolds have come to play a crucial role in the development and understanding of computational algorithms for the solution of problems i...
Creator:
Arnold, Douglas N. (University of Minnesota, Twin Cities)
Created:
2013-10-28
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
Recent progress has shown that the abstract space of persistence diagrams is Polish, and found necessary and sufficient conditions for a set to be compact. This also allowed for the definition of Frechet means, a construction which is possible for any metric space. Since the Frechet mean is a set, not an element, there were no guarantees that th...
Creator:
Munch, Elizabeth (University of Minnesota, Twin Cities)
Created:
2013-10-10
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
Joint work with Ida Moltke, Martin Thiim and Thomas Hamelryck (The Bioinformatics Center, University of Copenhagen)So far, the most common approach to modeling local RNA 3-D structure has been to describe the local conformational space as discrete in a non-probabilistic framework. We present an original approach to modeling local RNA 3-D structu...
Creator:
Frellsen, Jes (University of Copenhagen)
Created:
2007-10-29
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
We develop a continuum theory for thermoelectric bodies following the framework of continuum mechanics and conforming to general principles of thermodynamics. For steady states, the governing equations for local fields are intrinsically nonlinear. However, under conditions of small variations of electrochemical potential, temperature and their g...
Creator:
Liu, Liping (Rutgers, The State University Of New Jersey)
Created:
2012-09-14
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
Control systems theory has laid out a powerful framework for modularly analyzing and designing the dynamics of interconnected input/output dynamical systems, wherein an interconnection is traditionally viewed as a one-way interaction. Whether biomolecular networks can be modularly analyzed and designed is one of the most vexing questions in syst...
Creator:
Del Vecchio, Domitilla (Massachusetts Institute of Technology)
Created:
2015-09-30
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
Unit commitment and dispatch of generation in electricity markets involves the ISO sending target quantity instructions to each generator. Ideally, energy prices provide incentives for profit maximizing market participants to comply with efficient commitment and dispatch instructions in the short-term, and to develop new generation (based on ant...
Creator:
Baldick, Ross (The University of Texas at Austin)
Created:
2016-05-11
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
Several models have been proposed in order to describe cell communities self-organisation. One of them consists in coupling a multidimensional scalar conservation law with an elliptic equation which gradient determines the flux in the conservation law. In dimension larger than 1, the model looses all nice properties of hyperbolic conservation la...
Creator:
Perthame, Benoit (Université de Paris VI (Pierre et Marie Curie))
Created:
2009-07-21
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
Just as the number of real roots of a real univariate quadratic depends on the sign of the discriminant, the topological behavior of real zero sets depends on (more general) A-discriminant variety complements. More recently, in numerical linear algebra (and nonlinear work of Shub, Smale, Beltran, Pardo, and other authors), the relationship betwe...
Creator:
Rojas, J. Maurice (Texas A & M University)
Created:
2007-04-20
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
The complex system of actin filaments spanning the volume of amoving cell can be subdivided into distinct zones differing intheir dynamic behaviour, structure and function and ordered inspace sequentially beginning from the cell leading edge towardsthe cell interior. The first two zones are the lamellipodium,which underlies the cell membrane at ...
Creator:
Kozlov, Michael M. (Tel Aviv University)
Created:
2008-05-27
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
Clustering and ranking is often based on pairwise similarities (metric data) or comparisons (ordinal data). Most methods assume that the entire collection of all possible pairwise similarities or comparisons are known, but in high-dimensional settings there may be missing data and/or the costs of collecting this information may be prohibitive. T...
Creator:
Nowak, Robert (University of Wisconsin, Madison)
Created:
2011-09-26
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
We present a novel active learning algorithm for community detection on networks. Our proposed algorithm uses a Maximal Expected Model Change (MEMC) criterion for querying network nodes label assignments. MEMC detects nodes that maximally change the community assignment likelihood model following a query. Our work is inspired by detection in the...
Creator:
Kushnir, Dan (Nokia Bell Labs)
Created:
2020-11-06
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
In this work we discuss the problem of active learning. We present an approach 2 that is based on A-optimal experimental design of ill-posed problems and show 3 how one can optimally label a data set by partially probing it, and use it to train 4 a deep network. We present two approaches that make different assumptions on 5 the data set. The fir...
Creator:
Haber, Eldad (University of British Columbia)
Created:
2020-11-11
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
Adaptive sampling, also called 'Active Learning', uses informationgleaned from previous measurements (e.g., feedback) to guide and focusthe sampling process. Theoretical and experimental results have shownthat adaptive sampling can dramatically outperform conventionalnon-adaptive sampling schemes. I will review some of the mostencouraging theore...
Creator:
Nowak, Robert (University of Wisconsin, Madison)
Created:
2005-12-08
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
We begin from reviewing two concepts, motility in living systems, and active matter (also known as active materials). The main part of the talk is concerned with PDE models of two specific types of active matter: (i) suspensions of swimming bacteria and (ii) active gels that are networks of cross linked filaments subjected to action of energy tr...
Creator:
Berlyand, Leonid (The Pennsylvania State University)
Created:
2018-01-19
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
Contrasting the widespread application of data science methods and ever increasing volumes of data, human supervision capacities remain limited. Thus, the efficient allocation of limited resources is required, for example by selection of data for inspection, annotation, or processing.In this talk, we study active sampling approaches, which provi...
Creator:
Krempl, Georg (Otto-von-Guericke-Universität Magdeburg)
Created:
2016-09-15
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
Recent work with collaborators has been focused on understanding thedifferent features regarding well-posedness and regularity issues of the incompressible porous media and the surface quasi-geostrophic equation. In this talk we will discuss solutions with infinite energy and contour dynamics of patches.
Creator:
Cà³rdoba, Diego (Consejo Superior de Investigaciones Cientàficas (CSIC))
Created:
2010-02-23
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
Self-propelled bacteria are marvels of nature. If we can control their dynamics, we could use it to power microsystems of the future. Unfortunately, bacteria swim mostly randomly in isotropic liquids such as water. It is difficult to control their dynamics by factors other than transient gradients of nutrients; visual, acoustic and tactile commu...
Creator:
Lavrentovich, Oleg (Kent State University)
Created:
2018-01-16
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
Computer simulations based on the Hybrid Discrete-Continuous(HDC) mathematicalmodel of cancer invasion (Anderson et al., Cell. 2006,127:905)predict that the degree of severityof the tumor microenvironment (tmE) directly impacts on theemergence of invasion. Moreprecisely, harsh ME conditions (e.g., hypoxia, discontinuousmatrix, inflammation) sele...
Creator:
Quaranta, Vito (Vanderbilt University)
Created:
2008-03-05
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
The Metropolis Algorithm is an extremely useful and popular method of approximately sampling from complicated probability distributions. "Adaptive" versions automatically modify the algorithm while it runs, to improve its performance on the fly, but at the risk of destroying the Markov chain properties necessary for the algorithm to be valid. I...
Creator:
Rosenthal, Jeffrey (University of Toronto)
Created:
2021-03-23
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
The interplay of experimental observations with mathematical models often requires conditioning models on data---for example, inferring the coefficients or boundary conditions of partial differential equations from noisy functionals of the solution field. The Bayesian approach to these problems in principle requires posterior sampling in high or...
Creator:
Marzouk, Youssef (Massachusetts Institute of Technology)
Created:
2013-01-18
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
The Fock operator, which appears in the widely used Hartree-Fock theory and Kohn-Sham density functional theory with hybrid exchange-correlation functionals, plays a central role modern quantum chemistry and materials science. The computational cost associated with the Fock exchange operator is however very high. In a simplified setting, the Har...
Creator:
Lin, Lin (University of California, Berkeley)
Created:
2017-04-27
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
Adaptivity is an essential tool in modern scientific andengineering computation that allows one to optimize thecomputational effort by locating the degrees of freedom wherethey are most needed, that is in regions of rapid solutionvariation. Adaptive finite element methods (AFEM) are the mostpopular and effective numerical methods to solve ellipt...
Creator:
Nochetto, Ricardo H. (University of Maryland)
Created:
2010-11-29
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
I will present a computational method for simulating the dynamics of atomic systems on time scales much longer than can be accessed with classical dynamics. Possible reaction mechanisms available to the system are found by exploring the potential energy surface from minima to find nearby saddle points. Reaction rates are then calculated using ha...
Creator:
Henkelman, Graeme (The University of Texas at Austin)
Created:
2009-05-18
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
We propose a new approach to classical detection problem of discriminationof a true signal from an interferent signal. We show that the detectionperformance, as quantified by the receiver operating curve (ROC), can besubstantially improved when the signal is represented by a multi-componentdata set that is actively manipulated by a shaped probin...
Creator:
Levis, Robert J. (Temple University)
Created:
2005-11-09
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
The analysis of adaptive finite element methods for the approximation of partial differential equations is well established and has been successfully applied to a variety of problems (ranging from source problems to eigenvalue problems).In the framework of eigenvalue problems, we review the main issues related to the approximation of multiple ei...
Creator:
Boffi, Daniele (Università di Pavia)
Created:
2014-10-23
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
In this talk, we give an overview of adaptive wavelet methods for solving operator equations. In particular, we will focus on the following topics: The application of these methods to time evolution problems as parabolic problems and the instationary Stokes system; the advantage of the application of tensor product wavelets and the role of aniso...
Creator:
Stevenson, Rob (Universiteit van Amsterdam)
Created:
2010-11-03
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
A key issue in precision medicine is to uncover and utilize interactions between treatments and one's genetic and environmental risk factors. Due to the polygenic nature, testing for the interaction between a treatment and one's genetic features like a set of SNPs involves testing on a high-dimensional parameter. For such a purpose, it is critic...
Creator:
Pan, Wei (University of Minnesota, Twin Cities)
Created:
2018-11-08
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
Most supervised machine learning algorithms assume that each training data point is paired with an accurate training label (for classification) or value (for regression). However, obtaining accurate training label information is often time consuming and expensive, making it infeasible for large data sets, or may simply be impossible to provide g...
Creator:
Zare, Alina (University of Florida)
Created:
2018-10-26
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
In the past decade, big data has exploded onto the scene within the atmospheric science community. With advancements in computing technology and knowledge facilitating the development of high-resolution model simulations and observational analyses, a number of data sets exist for researchers within and outside this field of study. This talk will...
Creator:
Kennedy, Aaron (University of North Dakota)
Created:
2017-10-26
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
We have applied new experimental and computational approaches to understand the mechanical events of adherent cells. While the extensive use of flexible substrates has lead to excellent understanding of traction forces, introduction of long polymers into the cytoplasm has started to shed light on weak gradients of forces generated by the cortex....
Creator:
Wang, Yu-li (University of Massachusetts Medical School, Worcester Campus)
Created:
2008-05-28
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
In many physical systems it is believed that one can describe parts of the system by classical and parts of the system by quantum mechanics.In this lecture I explain how to rigorously derive such effective 'mixed quantum-classical' descriptions from the underlying quantum mechanicsfor the whole system. The important mechanism is adiabatic decoup...
Creator:
Teufel, Stefan (Eberhard-Karls-Universität Tübingen)
Created:
2009-01-11
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
Adiabatic perturbation theory is a general scheme that allows for the mathematically rigorous derivationof effective equations in quantum mechanical slow-fast systems. In this lecture I explain how to justify andcompute corrections to the time-dependent Born-Oppenheimer approximation. In the second part I presentsome recent results (jointly with...
Creator:
Teufel, Stefan (Eberhard-Karls-Universität Tübingen)
Created:
2009-01-16
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
We consider a system of hyperbolic-parabolic equations describinga material instability mechanism associated to the formation ofshear bands at high strain-rate plastic deformations of metals. We consider the case of adiabatic shearing and derive a quantitative criterion for the onset of instability: Using ideas from the theory of relaxation syst...
Creator:
Tzavaras, Athanasios E. (University of Maryland)
Created:
2009-07-28
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
Joint work with Chunyan Huang, Christoph Schwab and GerritWelper.The success of adaptive (wavelet) methods for operator equations relies on well-posedness ofsuitable variational formulations and on theavailability of Riesz bases (or frames) for the corresponding energy space provided thatthe corresponding representation of the operator is in a c...
Creator:
Dahmen, Wolfgang (RWTH Aachen)
Created:
2010-11-04
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
I will present a direct constrained minimization (DCM) algorithmfor solving the Kohn-Sham equations. The key ingredients of thisalgorithm involve projecting the Kohn-Sham total energy functionalinto a sequences of subspaces of small dimensions and seeking theminimizer of total energy functional within each subspace. Theminimizer of a subspace en...
Creator:
Yang, Chao (Lawrence Berkeley National Laboratory)
Created:
2008-10-02
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
We present a direct imaging algorithm for both the location and geometry of extended targets. Our algorithm is based on a physical factorization of the response matrix of an active array. A resolution and noise level based thresholding is used for regularization. Our algorithm is extremely simple and efficient since no forward solver or iteratio...
Creator:
Zhao, Hongkai (University of California, Irvine)
Created:
2005-10-20
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
Reflected Brownian motion (RBM) in a wedge is a 2-dimensional stochastic process $Z$ whose state space in $\mathbb{R}^2$ is given in polar coordinates by $S=\{(r,\theta): r \geq 0, 0 \leq \theta \leq \xi\}$ for some $0 < \xi < 2 \pi$. Let $\alpha= (\theta_1+\theta_2)/\xi$, where $-\pi/2 < \theta_1,\theta_2 < \pi/2$ are the directions of reflecti...
Creator:
Reed, Joshua (New York University)
Created:
2018-05-15
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
This talk will describe a new discontinuous Galerkin model that we've developed for use in many geophysical fluid dynamics including: 1) the atmosphere and 2) coastal ocean; we will focus on the coastal ocean in this talk. The strengths of this model include: 1) arbitrarily high-order spatial discretization via the discontinuous Galerkin method,...
Creator:
Giraldo, Frank (Naval Postgraduate School)
Created:
2014-10-15
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
Abstract: The Kaczmarz algorithm is a method for solving linear systems of equations that was introduced in 1937. The algorithm is a powerful tool with many applications in signal processing and data science that has enjoyed a resurgence of interest in recent years. We'll discuss some of the history of the Kaczmarz algorithm as well as describ...
Creator:
Weber, Eric (Iowa State University)
Created:
2022-04-26
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
UnitedHealthcare's Advanced Research and Analytics (ARA) teams solve business problems across all internal lines of business. During this presentation we will discuss 3-4 high impact business problems and how the ARA team solved or is trying to solve them. We will also discuss mathematics and applied problem solving in Healthcare with a focus on...
Creator:
Haupt, Jason (UnitedHealth Group)
Created:
2016-02-05
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
In presence of market prices, energy utilities have to evaluate and hedge theimpact of energy prices fluctuations on their Profit and Loss. This requires, in particular,to develop efficient computational methods to price, optimize and hedge physical assets(such as thermal power plants). Mathematically, the problem of pricing a thermal assetcan b...
Creator:
Oudjane, Nadia (Electricite de France (EDF))
Created:
2012-05-17
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
Recent advances in optical sensing technology (miniaturization and low-cost architectures for spectral imaging) and sensing platforms from which such imagers can be deployed (e.g. handheld devices, unmanned aerial vehicles) have the potential to enable ubiquitous multispectral and hyperspectral imaging on demand to support geospatial analysis. O...
Creator:
Prasad, Saurabh (University of Houston)
Created:
2018-10-25
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
The first completely sequenced genome, the virus Lambda at 50,000 nucleotides, was sequenced via the shotgun method by Sanger and coworkers at Cambridge in 1981. The shotgun method consists of randomly sampling and determining 500-700 nucleotide 'reads' and then assembling them to reconstruct the sampled sequence. It was long believed that this ...
Creator:
Myers, Gene (University of California, Berkeley)
Created:
2003-05-06
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
Self assembly is the idea of creating a system whose component parts spontaneously assemble into a structure of interest.In this talk I will outline our research program aimed at creating self-assembled structures out of very small spheres,that bind to each other on sticking. The talk will focus on (i) some fundamental mathematical questions inf...
Creator:
Brenner, Michael P. (Harvard University)
Created:
2009-12-10
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
Angiogenesis, consisting in the formation of blood vessels from preexisting ones, is of crucial importance in pathological situations such as cancer and diabetes and is a therapeutic target for these two diseases. We have developed protein and sugar arrays probed by surface plasmon resonance (SPR) imaging to identify binding partners of proteins...
Two major players in a smart grid are renewables and flexible consumption. The former is necessitated by global concerns of sustainability and greenhouse gas emissions, and dwindling resources of fossil fuels. The latter is enabled through the feasibility of fast and large-scale communication and the growing acceptance and economic potential of ...
Creator:
Annaswamy, Anuradha M. (Massachusetts Institute of Technology)
Created:
2016-05-12
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
Discretizations of PDEs have traditionally relied on structured meshes. Requirements for geometric flexibility, both to conform to highly irregular geometries as in topographical and urban features as well as to achieve local refinement in critical areas, have led to an increased use of unstructured meshes, often in the form of polygonal-type el...
Creator:
Flyer, Natasha (National Center for Atmospheric Research)
Created:
2014-10-17
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
In this talk, we present a simple and efficient method for rotating aspherical harmonic expansion. This is a well-studied problem, arisingin classical scattering theory, quantum mechanics and numericalanalysis, usually addressed through the explicit construction of theWigner rotation matrices. Existing fast algorithms, based onrecurrence relatio...
Creator:
Gimbutas, Zydrunas (New York University)
Created:
2010-08-04
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
In this talk I will introduce the back-and-forth method, a new algorithm to efficiently solve the optimal transportation problem for a general class of strictly convex transportation costs. Given two probability measures supported on a discrete grid with n points, the method computes the optimal map in O(n log(n)) operations using O(n) storage s...
Creator:
Jacobs, Matthew (University of California, Los Angeles)
Created:
2020-11-11
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
Data classification, where the goal is to divide data into predefined classes, is a fundamental problem in machine learning with many applications, including the classification of 3D sensory data. In this paper, we present a data classification method which can be applied to both semi-supervised and unsupervised learning tasks. The algorithm ...
Creator:
Rapinchuk, Ekaterina (Michigan State University)
Created:
2020-09-14
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.