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....
Within a species, the abundance of individuals varies in time and space. This dissertation research examines processes giving rise to patterns of spatial and temporal variation in the abundance of multiple species of forest-breeding migratory...
Calanus finmarchicus -- Georges Bank. ; Calanus finmarchicus -- Maine Gulf of. ; Calanus finmarchicus -- North Atlantic Ocean.
Calanus finmarchicus, a kind of marine zooplankton, plays an important ecological role throughout the North Atlantic. Striking seasonal variations exist in its abundance and distribution in the Gulf of Maine/Georges Bank region. On the Bank in...
A fiber can transmit around 25 Tbit/s, but electronic signal processing today is performed at much slower speeds, usually 1-10 Gbit/s. To avoid this "bottleneck" in optical fiber communication systems, all signal processing will have to be done...
2-D and 3-D woven composites are becoming materials of choice for the forming of structural parts for an ever-increasing range of industries from infrastructure to aerospace. Research has shown that for a wide range of structural composites, in...
The Maine Coastal Current (MCC) flows south-westward along the New England coast in the Gulf of Maine. Red tides, river-borne pollutants, and biological species are hypothesized to be transported by the MCC. The transport pathways, and their...
Magnetic resonance elastography (MRE) is a technique to produce images of the mechanical properties of tissue, which are indicative of a variety of diseases. Tissue motions measured using MRI are used to solve an inverse problem to recover...
The main research objective of this thesis is to address distributed target tracking for mobile sensor networks. Based on real-life limitations, we are particularly interested in mobile sensors with Limited Sensing Range (LSR). There are three...
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...
'The control of waves using periodic structures is crucial for modern optical, electromagnetic and acoustic devices such as diffraction gratings, filters, photonic crystals, solar cells, sensors, and absorbers. We present a high-order accurate...
We study motion planning problems, finding trajectories that connect two configurations of a system, from two different perspectives: optimality and survivability. For the problem of finding optimal trajectories, we provide a model in which the...
Agent-based policy learning in complex and uncertain environments is challenged by escalating computational complexity with the size of the task space (action choices and environmental states) as well as the number of agents. Nonetheless, there is...
Breast -- Cancer -- Tomography. ; Breast -- Cancer -- Imaging. ; Breast -- Cancer -- Diagnosis. ; Near infrared reflectance spectroscopy. ; Image processing -- Digital techniques.
Near-infrared (NIR) light has the potential to be used as a non-invasive means of diagnostic imaging within the human breast. Due to the diffusive nature of light in tissue, computational model-based methods are required for functional imaging...
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...
Ocean circulation -- Georges Bank -- Mathematical models. ; Submarine topography -- Georges Bank.
A two-dimensional continuously-stratified model is derived for the study of instability properties of oceanic density fronts in the presence of sloping bottom topography. While the model retains several traditional assumptions, such as uniformity...
Motivated by the goal of investigating the dynamics of the electroweak phase transition in the early Universe, a study of dynamical aspects of nonlinear field-theoretical systems is performed. Symmetric and asymmetric double-well potentials in the...
Gene set testing has become a critical tool for interpreting the results of high-throughput genomic experiments. Despite the development of robust statistical methods and extensive gene set collections, however, the results from gene set testing...
In order to most effectively investigate protein structure and improve protein function, it is necessary to carefully plan appropriate experiments. The combinatorial number of possible experiment plans demands effective criteria and efficient...
Three-dimensional imaging in medicine -- Mathematical models. Diagnostic imaging -- Digital techniques. Brain -- Magnetic resonance imaging. Inverse problems (Differential equations).
An accurate registration between the preoperative images and the current surgical scene is critical to image-guided neurosurgery. However, during a neuro-surgical intervention, brain tissues shift and degrade the accuracy of the registration....
Protein complexes play vital roles in cellular processes within living organisms. They are formed by interactions between either different proteins (hetero-oligomers) or identical proteins (homo-oligomers). In order to understand the functions of...
Medical imaging methods have become increasingly important in diagnosing diseases and assisting therapeutic treatment. In particular, early detection of breast cancer is considered as a critical factor in reducing the mortality rate of women....
Breast -- Magnetic resonance imaging. Breast -- Tomography. Near infrared spectroscopy. Optical tomography. Imaging systems -- Design and construction. Diagnostic imaging -- Mathematical models.
Molecular imaging of cancer features is a critical part of advancing better tools for oncology management and drug discovery, yet it is still evolving as a useful tool. Diffuse Fluorescence Tomography (FT) is one approach to molecular imaging, used...
Microwave spectroscopy. Imaging systems -- Design and construction. Diagnostic imaging -- Digital techniques. Breast -- Cancer -- Diagnosis. Microwave imaging in medicine.
Microwave spectroscopy has been investigated as a possible modality for breast imaging because of the significant contrast in electrical properties between normal and malignant tissue over the microwave spectrum. A liquid-coupled, non-contacting...
Magneto-spectroscopy is used to characterize the confinement properties of strain-induced quantum wires and dots. The wires and dots are low energy regions in an ordinary GaAs/AlGaAs quantum well that are formed when microscopic...
As the ubiquitous complexity of common disease has become apparent, so has the need for novel tools and strategies that can accommodate complex patterns of association. In particular, the analytic challenges posed by the phenomena known as...
Optical tomography. Fluorescence. Imaging systems -- Design and construction. Diagnostic imaging -- Mathematical models. Brain -- Diseases -- Diagnosis. Brain -- Magnetic resonance imaging.
Fluorescent molecules targeted to reveal information on tissue function have been used as research tools in ex vivo and subsurface characterization of diseased tissue for years. Exploiting this specificity for in vivo imaging through centimeters of...
Electric generators -- Windings. Electric inductors -- Design and construction -- Mathematical models. Electric current converters -- Design and construction -- Mathematical models. Energy dissipation -- Mathematical models.
Magnetic components for high-frequency power conversion applications can have significant losses that compromise the performance of the converter. In particular, winding losses can be large due to high-frequency effects that are difficult to model...
In this thesis, the dynamics of long-lived, time-dependent, coherent field configurations, known as oscillons, are investigated in the presence of an expanding background. In a (1+1)-dimensional expanding spacetime, scalar-field oscillon lifetimes...
Infrared imaging. Image reconstruction. Optical images -- Mathematical models. Breast -- Imaging. Infrared radiation in medicine.
Finite element based reconstruction algorithms for optical property profiling in biological tissues have been developed, implemented and evaluated using simulated data and laboratory measurements obtained with near infrared continuous wave (cw) and...
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...