If A is a finite-dimensional algebra with automorphism group G, then varieties of generating r-tuples of elements in A, considered up to G-action, produce a sequence of varieties B(r) approximating the classifying space BG. I will explain how this construction generalizes certain well-known examples such as Grassmannians and configuration spaces...
Creator:
Williams, Ben (University of British Columbia)
Created:
2022-08-05
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
In an approach similar to Ewald's method for evaluating lattice sums, we split the application of Helmholtz Green's functions between the spatial and the Fourier domains and, for any finite accuracy, approximate their kernels.In the spatial domain we use a near optimal linear combination of decaying Gaussians with positive coefficients and, in t...
Creator:
Beylkin, Gregory (University of Colorado)
Created:
2010-08-04
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
Approximation of positive polynomials by sums of squares has importantapplications to polynomial optimisation. In this talk, I will surveythe main recent results achieved on that topic:I will consider positive (respectively, non-negative) polynomials oncompact (respectively, unbounded) semi-algebraic sets. I will discussrepresentations in the as...
Creator:
Kuhlmann, Salma (University of Saskatchewan)
Created:
2007-01-20
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
The approximation error approach was proposed in [J. Kaipio \& E. Somersalo, Statistical and Computational Inverse Problems, Springer, 2004] for handling modelling errors due to model reduction and unknown nuisance parameters in inverse problems. In this talk, we discuss the application of the approximation error approach for approximate margina...
Creator:
Kolehmainen, Ville (University of Eastern Finland)
Created:
2017-09-07
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
The Steiner polynomial of a solid body in R^d is of degree d and describes the volume as a function of the thickening parameter (parallel body). There are d+1 coefficients which are used to define the d+1 intrinsic volumes of the solid body. In d=2 dimensions, the first intrinsic volume is the length, and in d=3 dimensions, it is the total mean ...
Creator:
Edelsbrunner, Herbert (Institute of Science and Technology Austria (IST))
Created:
2014-03-04
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
The inverse photolithography problem is a key step in the production of integrated circuits. I propose a regularization and computation strategy for this optimization problem, whose key feature is a regularization procedure for a suitable thresholding operation. The validity of the method is shown by a convergence analysis and by numerical exper...
Creator:
Rondi, Luca (Università di Trieste)
Created:
2016-12-14
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
We present an approximation algorithm for network revenue management problems. In our approximation algorithm, we construct an approximate policy using value function approximations that are expressed as linear combinations of basis functions. We use a backward recursion to compute the coefficients of the basis functions in the linear combinatio...
Creator:
Topaloglu, Huseyin (Cornell University)
Created:
2018-10-04
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
We consider solving for a single component of the solution to a system of linear equations, Ax = b, where A is an n-by-n real-valued matrix, and b is a real-valued n dimensional vector. This equation can equivalently be written as x = Gx + z for an appropriate choice of G and z. We are interested in utilizing the sparsity of G (equivalently of A...
Creator:
Lee, Christina E (Massachusetts Institute of Technology)
Created:
2015-05-20
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
For discretizations of partial differential equations, the standard methods for numerically solving Lyapunov and Riccati equations (as for example implemented in matlab) are usually not suitable since the computational effort and storage requirements are too high. Analysis of the underlying partial differential equation shows that often good low...
Creator:
Opmeer, Mark (University of Bath)
Created:
2016-03-16
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
When developing CAD-type intersection algorithms forNonUniform Rational B-splines surfaces (NURBS) is importantto ensure that the algorithm identifies all intersectionbranches. For transversal intersections this is fairlystraight forward. For singular or near singular intersection,when the surfaces are close and near parallel, thetraditional app...
Creator:
Dokken, Tor (SINTEF)
Created:
2007-05-31
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
Duplex DNA, the genetic material in living cells, is an unusually inflexible biopolymer. The persistence length of duplex DNA corresponds to 150 base pairs under physiological conditions. Surprisingly, the physical origin of this DNA stiffness is unknown. In particular, the contribution of the high negative charge density of DNA to its stiffness...
Creator:
Maher, James (Mayo Clinic)
Created:
2007-09-20
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
Probabilistic Tsunami Hazard Assessment (PTHA) for a coastal community or harbor can be performed by running a tsunami propagation/inundation code with initial seafloor deformations sampled from some presumed probability distribution of possible earthquakes. In addition to uncertainty in the tsunami source, tidal uncertainty has to be incorporat...
Creator:
LeVeque, Randall J. (University of Washington)
Created:
2014-10-16
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
Day 3: We describe several possible approaches to extending the classical theory of OMT to the multivariate (matrix-valued) case. Some applications to spectral analysis will be given.
Creator:
Tannenbaum, Allen (State University of New York, Stony Brook (SUNY))
Created:
2014-06-11
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
10:50 - 11:00 a.m. Program Opens "If you wish..." (With Music Under) Program Closes: "... School of the Air." Music Out This program is about young people learning trades in colonial America.
Creator:
University of Minnesota. Radio Station KUOM
Created:
1975-11
Contributed By:
University of Minnesota Libraries, University Archives.
Joint work with Doug Oldenburg.Image appraisal in geophysical inverse problem can provide insight into theresolving capability and uncertainty of estimates. Although a rigorous approachto solve nonlinear appraisal analysis is still lacking but several methods havebeen proposed in the past such as linearized Backus-Gilbert analysis, funnelfunctio...
Creator:
Routh, Partha S. (Boise State University)
Created:
2005-10-18
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
Recently we introduced a framework for applying subgradient methods to solve general convex, conic optimization problems. The framework, once seen, is 'obvious,' but had not appeared in the literature, a blind spot. Quite recently we posted a refinement of the framework in the special case of hyperbolic programming. Hyperbolicity cones have alge...
Creator:
Renegar, James (Cornell University)
Created:
2016-01-26
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
Numerical grid generation, that is, structured grid generation, is the development of a generalized curvilinear coordinate system. Originally designed for solving computational fluid dynamics problems over oddly shaped domains, structured techniques have competed with various unstructured methods such as Voronoi or Delaunay triangulations and qu...
Creator:
Saunders, Bonita V. (National Institute of Standards and Technology)
Created:
2010-04-09
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
