Now showing items 1-20 of 37

• #### Predicting solvation free energies and thermodynamics in polar solvents and mixtures using a solvation-layer interface condition ﻿

(2017)
We demonstrate that with two small modifications, the popular dielectric continuum model is capable of predicting, with high accuracy, ion solvation thermodynamics (Gibbs free energies, entropies, and heat capacities) in ...
• #### Reconstruction of Lamé Moduli and Density at the Boundary Enabling Directional Elastic Wavefield Decomposition ﻿

(2017)
We consider the inverse boundary value problem for the system of equations describing elastic waves in isotropic media on a bounded domain in $\mathbb{R}^3$ via a finite-time Laplace transform. The data are the dynamical ...
• #### An adaptive multiscale algorithm for efficient extended waveform inversion ﻿

(2017)
Subsurface-offset extended full-waveform inversion (FWI) may converge to kinematically accurate velocity models without the low-frequency data accuracy required for standard data-domain FWI. However, this robust alternative ...
• #### Topological Schemas of Cognitive Maps and Spatial Learning ﻿

(2016)
Spatial navigation in mammals is based on building a mental representation of their environment-a cognitive map. However, both the nature of this cognitive map and its underpinning in neural structures and activity remains ...
• #### A Topological Model of the Hippocampal Cell Assembly Network ﻿

(2016)
It is widely accepted that the hippocampal place cells' spiking activity produces a cognitive map of space. However, many details of this representation's physiological mechanism remain unknown. For example, it is believed ...
• #### Levetiracetam mitigates doxorubicin-induced 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, ...
• #### Modulation of Orthographic Decoding by Frontal Cortex ﻿

(2016)
Opinions are divided on whether word reading processes occur in a hierarchical, feedforward fashion or within an interactive framework. To critically evaluate these competing theories, we recorded electrocorticographic ...
• #### Scattering and dip angle decomposition based on subsurface offset extended wave-equation migration ﻿

(2016)
An angle-dependent reflection coefficient is recovered by seismic migration in the angle domain. We have developed a postmigration technique for computing scattering and dip angle common-image gathers (CIGs) from seismic ...
• #### Inverse Boundary Value Problem For The Helmholtz Equation: Quantitative Conditional Lipschitz Stability Estimates ﻿

(2016)
We study the inverse boundary value problem for the Helmholtz equation using the Dirichlet-to-Neumann map at selected frequencies as the data. A conditional Lipschitz stability estimate for the inverse problem holds in the ...
• #### A DEIM Induced CUR Factorization ﻿

(2016)
We derive a CUR approximate matrix factorization based on the discrete empirical interpolation method (DEIM). For a given matrix ${\bf A}$, such a factorization provides a low-rank approximate decomposition of the form ...
• #### Optimal Convergence Rates Results for Linear Inverse Problems in Hilbert Spaces ﻿

(2016)
In this article, we prove optimal convergence rates results for regularization methods for solving linear ill-posed operator equations in Hilbert spaces. The results generalizes existing convergence rates results on ...
• #### Residual-Based Adaptivity and PWDG Methods for the Helmholtz Equation ﻿

(2015)
We present a study of two residual a posteriori error indicators for the plane wave discontinuous Galerkin (PWDG) method for the Helmholtz equation. In particular, we study the $h$-version of PWDG in which the number of ...
• #### A Comparison of High Order Interpolation Nodes for the Pyramid ﻿

(2015)
The use of pyramid elements is crucial to the construction of efficient hex-dominant meshes [M. Bergot, G. Cohen, and M. Duruflé, J. Sci. Comput., 42 (2010), pp. 345--381]. For conforming nodal finite element methods with ...
• #### Convergence of a high order method in time and space for the miscible displacement equations ﻿

(2015)
A numerical method is formulated and analyzed for solving the miscible displacement problem under low regularity assumptions. The scheme employs discontinuous Galerkin time stepping with mixed and interior penalty discontinuous ...
• #### The Minimalﾠk-Core Problem for Modelingﾠ k-Assemblies ﻿

(2015)
The concept of cell assembly was introduced by Hebb and formalized mathematically by Palm in the framework of graph theory. In the study of associative memory, a cell assembly is a group of neurons that are strongly connected ...
• #### Cytoplasmic sphingosine-1-phosphate pathway modulates neuronal autophagy ﻿

(2015)
Autophagy is an important homeostatic mechanism that eliminates long-lived proteins, protein aggregates and damaged organelles. Its dysregulation is involved in many neurodegenerative disorders. Autophagy is therefore a ...
• #### Numerical method of characteristics for one-dimensional blood flow ﻿

(2015)
Mathematical modeling at the level of the full cardiovascular system requires the numerical approximation of solutions to a one-dimensional nonlinear hyperbolic system describing flow in a single vessel. This model is often ...
• #### An approximate inverse to the extended Born modeling operator ﻿

(2015)
Given a correct (data-consistent) velocity model, reverse time migration (RTM) correctly positions reflectors but generally with incorrect amplitudes and wavelets. Iterative least-squares migration (LSM) corrects the ...
• #### An Efficient Gauss--Newton Algorithm for Symmetric Low-Rank Product Matrix Approximations ﻿

(2015)
We derive and study a Gauss--Newton method for computing a symmetric low-rank product $XX^{{T}}$, where $X \in{\mathbb{R}}^{n\times k}$ for $k<n$, that is the closest to a given symmetric matrix \$A \in{\mathbb{R}}^{n\times ...
• #### Horizontal contraction in image domain for velocity inversion ﻿

(2015)
A kinematically correct choice of velocity focuses subsurface offset image gathers at a zero offset. Infinitesimal warping from the current image toward its focus can be approximated by a horizontal contraction. The image ...