Browsing Computational and Applied Mathematics by Title
Now showing items 413432 of 774

Joint Inversion Using the Convolutional Model
(200004)A detailed imaging of an acoustic medium via a seismic experiment requires an accurate representation of the source. A joint source and reflectivity inversion may provide the means to obtain the desired detail. Joint ... 
Karmarkar as a Classical Method
(198703)In this work we demonstrate that the Karmarkar algorithm for linear programs results from the classical approach of first transforming nonnegativity constraints into equality constraints by adding squaredslack variables ... 
Kinematics of ShotGeophone Migration
(200504)Prestack migration methods based on data binning produce {\em kinematic artifacts}, i.e. coherent events not corresponding to actual reflectors, in the prestack image volume. Shotgeophone migration, on the other hand, ... 
KrylovSecant Methods for Solving Systems of Nonlinear Equations
(199509)We present a novel way of reusing the Krylov information generated by GMRES for solving the linear system arising within a Newton method. Our approach departs from the theory of secant preconditioners developed by Martinez ... 
Landau Collision Integral Solver with Adaptive Mesh Refinement on Emerging Architectures
(2017)The Landau collision integral is an accurate model for the smallangle dominated Coulomb collisions in fusion plasmas. We investigate a high order accurate, fully conservative, finite element discretization of the nonlinear ... 
Large Time Asymptotics in Contaminant Transport in Porous Media
(199411)In this paper we derive large time solutions of the partial differential equations modelling contaminant transport in porous media for initial data with bounded support. While the main emphasis is on two space dimensions, ... 
Layered Velocity Inversion: A Model Problem from Reflection Seismology
(198810)A simple model problem in exploration seismology requires that a depthvarying sound velocity distribution be estimated from reflected sound waves. For various physical reasons, these reflected signals or echoes have very ... 
Learning Circulant Sensing Kernels
(201201)In signal acquisition, Toeplitz and circulant matrices are widely used as sensing operators. They correspond to discrete convolutions and are easily or even naturally realized in various applications. For compressive ... 
LeastChange Secant Update Methods with Inaccurate Secant Conditions
(198311)In this paper, we investigate the role of the secant or quasiNewton condition in the sparse Broyden or Schubert update method for solving systems of nonlinear equations whose Jacobians are either sparse, or can be ... 
Levetiracetam mitigates doxorubicininduced DNA and synaptic damage in neurons
(2016)Neurotoxicity may occur in cancer patients and survivors during or after chemotherapy. Cognitive deficits associated with neurotoxicity can be subtle or disabling and frequently include disturbances in memory, attention, ... 
Limited Memory Block Krylov Subspace Optimization for Computing Dominant Singular Value Decompositions
(2013)In many dataintensive applications, the use of principal component analysis and other related techniques is ubiquitous for dimension reduction, data mining, or other transformational purposes. Such transformations often ... 
Limited Memory Block Krylov Subspace Optimization for Computing Dominant Singular Value Decompositions
(201203)In many dataintensive applications, the use of principal component analysis (PCA) and other related techniques is ubiquitous for dimension reduction, data mining or other transformational purposes. Such transformations ... 
Linear and Nonlinear Deconvolution Models
(198604)This dissertation considers computational methods for solving linear and nonlinear least squares problems arising from deconvolution applications. For the linear problems we propose a new preconditioner to speed up the ... 
Linearly Convergent Decentralized Consensus Optimization with the Alternating Direction Method of Multipliers
(201304)In a decentralized consensus optimization problem, a network of agents minimizes the summation of their local objective functions on a common set of decision variables, allowing only information exchange among neighbors. ... 
Local Analysis of Inexact QuasiNewton Methods
(198205)QuasiNewton methods are well known iterative methods for solving nonlinear problems. At each stage, a system of linear equations has to be solved. However, for large scale problems, solving the linear system of equations ... 
Local and Superlinear Convergence for Truncated Projections Methods
(198110)Least change secant updates can be obtained as the limit of iterated projections based on other secant updates. We show that these iterated projections can be terminated or truncated after any positive number of iterations ... 
Local and Superlinear Convergence of Structured Secant Methods from the Convex Class
(198801)In this paper we develop a unified theory for establishing the local and qsuperlinear convergence of the secant methods from the convex class that take advantage of the structure present in the Hessian in constructing ... 
Local Error Analysis of Discontinuous Galerkin Methods for AdvectionDominated Elliptic LinearQuadratic Optimal Control Problems
(20120815)This paper analyzes the local properties of the symmetric interior penalty upwind discontinuous Galerkin (SIPG) method for the numerical solution of optimal control problems governed by linear reactionadvectiondiffusion ... 
Logarithmic Indicators and the Identification of Subgroups of Variables in InteriorPoint Methods
(199309)The identification of certain groups of variables in optimization problems is an important issue and can be used to computational advantage. In this paper new logarithmic indicators are introduced. It is demonstrated that ...