Ultra-high molecular weight polyethylene (UHMWPE) remains the most common bearing material for total joint arthroplasty. Advances in radiation cross-linking and other post-consolidation treatments have led to a rapid differentiation of polyethylene...
Brain tissue mechanics are an important biomarker for neurological disorders, yet methods to obtain tissue information yield inconsistent conclusions. These techniques can be invasive or require excised tissue, where tissue function is altered from...
A new type of analytic expansion for use in stability calculations is presented and applied to the question of the stability of laminar solutions of the Navier-Stokes equation. This leads in a natural way to a model of the transition from laminar...
Through a series of case studies, signal processing and statistical tools, analyses of dynamic sea ice processes of drift, deformation, and ice pack expansion and decay are investigated for the Weddell Sea region during 1992. Cavitating fluid (CAV)...
Coherent states. Quantum field theory. Nonlinear theories.
In this thesis we study the properties of time-dependent, nontopological configurations and their effect on the macroscopic properties of a system described by a nonlinear field theory. These structures seem to be ubiquitous in relativistic field...
Boundary integral methods have long been used to solve boundary value problems for elliptic partial differential equations with piecewise constant coefficients, since they have several numerical advantages over conventional volume discretization....
Plasma instabilities. ; Ionospheric electron density. ; Ionosphere.
As a result of an unstable plasma stratification the nighttime equatorial ionosphere is subject to a variety of plasma instabilities known commonly as equatorial spread-F. In its fully developed form spread-F consists of large wedges of depleted...
Three-dimensional imaging in medicine -- Mathematical models. ; Stereoencephalotomy.
In the past, clinicians skilled at image-guided neurosurgery have relied solely on pre-operative scans for their navigational information. Often in the course of surgery, tissue is purposely retracted/resected or inadvertently moved resulting in a...
Two-phase flow -- Mathematical models. ; Gas dynamics -- Mathematical models. ; Kinetic theory of gases.
The kinetic theory based gas-dynamical computational method, due to (Prendergast and Xu, 1993: Xu and Prendergast, 1994) is generalized to two-phase flow computations. The Bhatnagar-Gross-Krook kinetic model is generalized to the case of two...
Biological conversion of biomass to fuels and chemicals offers recognized benefits. The absence of systematic methodologies for scaling up such conversion is an important issue related to realizing these benefits. This thesis addresses this scale...
Snow -- Permeability. ; Snow surveys -- Antarctica -- East Antarctica. ; Surfaces -- Areas and volumes. ; Gas flow. ; Porosity.
Recent field investigations of a megadunes region of East Antarctica provide evidence that differences in grain size, thermal conductivity, and permeability across a megadune are due to relative accumulation patterns in the absence of significant...
Most theoretical and computational studies of turbulence in Navier-Stokes fluids and/or guiding-center plasmas have been carried out in the presence of spatially periodic boundary conditions. In view of the frequently-reproduced result that...
Decompression sickness (DCS, or the "Bends") is a condition that afflicts hundreds of divers each year and is cause for concern for both the Navy, the Air Force, and NASA. Despite the fact that bubble formation is the purported cause of DCS...
Diagnostic imaging -- Mathematics. Expectation-maximization algorithms. Imaging systems in medicine -- Mathematics.
We have developed a general-purpose registration algorithm for medical images and volumes. The transformation between images is modeled as locally affine but globally smooth, and explicitly accounts for local and global variations in image...
Renewable energy sources are becoming increasingly important as sustainable alternatives to fossil fuels. One of these renewable sources, cellulosic biomass, is a relatively inexpensive and abundant resource that can be converted into liquid fuels...