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...
In the late 1960s, Ihara began work that led to the Ihara zeta function, a zeta function which is defined on a finite graph. This function is an interesting graph invariant which gives information on expansion properties of the graph. It also...
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...
Spectral theory is the subfield of differential geometry which provided the solution to Kac''s famous question, "Can you hear the shape of a drum?" That is, can we use the Laplace spectrum of a manifold to draw conclusions about its geometry or...
This thesis considers the two special sensor networks for future sensor network design: mobile sensor networks and hybrid network of sensors and robots. To investigate two types of networks, we abstract two most important aspects that are ingrained...
Optical tomography. ; Near infrared spectroscopy. ; Image analysis -- Mathematical models. ; Imaging systems -- Image quality -- Mathematical models. ; Image reconstruction -- Mathematical models. ; Least squares. Breast -- Tomography.
Diffuse optical tomography (DOT) has the potential to become a non-invasive and non-ionizing diagnostic imaging technique for breast cancer imaging. DOT uses near-infrared (NIR) light to illuminate the breast, generally through the use of fiber...
Brain -- Tomography. Magnetic resonance imaging -- Brain. Near infrared spectroscopy. Image processing -- Digital techniques.
Diffuse optical tomography (DOT) using near infrared (NIR) light has become a promising modality because it has the capability to non-invasively quantify oxygen saturation and hemoglobin content with potentially high temporal resolution and...
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...
Breast -- Cancer -- Tomography. Near infrared spectroscopy. Breast -- Cancer -- Imaging. Breast -- Cancer -- Diagnosis.
Near-infrared (NIR) light provides potential for a new approach to non-invasive detection, diagnosis and clinical management of breast cancer. Using NIR spectroscopic imaging techniques, the physiological information about breast tissue composition...
Microwave imaging (MI) is based on recovering dielectric properties (permittivity and conductivity) of materials. Over the last two decades, MI has attracted increasing interests in biomedical applications, in particular, for breast cancer...
This thesis investigates the embedding theory of orders in central simple algebras, placing a particular emphasis on the role that the phenomenon known as selectivity plays in the theory. Although the notion of selectivity is completely algebraic,...
Currently, the hypothesis that discrete auroral arcs are produced by fluxes of magnetospheric electrons accelerated along the ambient magnetic field into the ionosphere by linear/non-linear mechanisms associated with magnetic field-aligned currents...
Multiresolution image transformations have become commonplace tools for analyzing images for a number of applications, including enhancement and restoration. Powerful models for these applications have been developed in the transform domain of...
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...
Computer input-output equipment. ; Computational grids (Computer systems). ; High performance computing. ; Electronic data processing -- Distributed processing.
High-performance computing increasingly occurs on computational grids composed of heterogeneous and geographically distributed systems of computers, networks, and storage devices that collectively act as a single virtual computer. A key challenge...
Information retrieval -- Mathematical models. ; Electronic information resource searching. ; Computer algorithms. ; Decision making -- Data processing. ; Mathematical optimization.
This thesis presents a unified method for simultaneous solution of three problems in Information Retrieval--metasearch (the fusion of ranked lists returned by retrieval systems to elicit improved performance), efficient system evaluation (the...
We prove the existence of nontrivial multiparameter isospectral deformations of metrics on the classical compact simple Lie groups SO (n) (n = 9, n â‰¥11), Spin(n) (n = 9, n â‰¥11), SU (n) (n â‰¥7), and Sp (n) (n â‰¥5). The proof breaks into three...
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....
Motivated by quantum mechanics and geometric optics, it is a long-standing problem whether the length spectrum of a compact Riemannian manifold can be recovered from its Laplace spectrum. One route to proving that the length spectrum depends on the...
In this thesis, we study the dynamics of magnetic flows on compact nilmanifolds. Magnetic flows are generalizations of geodesic flows. They model the motion of a particle of unit mass and unit charge in a smooth manifold M in the presence of a...
'Orthogonal modular forms are algebraic modular forms arising from lattices in quadratic spaces. In this thesis, we define orthogonal modular forms, establish their basic properties, and then apply them to a case of ternary quadratic spaces to...
Arctic temperature and precipitation have been rising over recent decades, with implications for Greenland Ice Sheet (GrIS) mass balance, sea level rise, and thermohaline circulation via Arctic Ocean freshening. However, meteorological station data...
Brain mapping via EEG activation is a useful tool of basic neuroscience, and has wide clinical applications as well. The mapping is achieved by means of Event Related Potentials (ERPs), task-related changes in EEG time series. The methodology of...
Electroencephalography -- Data processing. ; Epilepsy -- Diagnosis. ; Signal processing -- Mathematics. ; Time-series analysis. ; Wavelets (Mathematics).
Visual interpretation of the EEG associated with an epileptic seizure (ictal EEG) can be cumbersome and sometimes misleading, due to rapid seizure spread, limited spatial resolution and the fact that signals of interest are often obscured by...
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...
Flexible fiber scopes are widely used in industry and medicine. Typical scopes are made using conventional optical components and order-packed flexible image bundles. The optical performance of a flexible scope is largely determined by that of the...
Plant genetic engineering. ; Plants -- Effect of cadmium on. ; Cadmium -- Physiological transport.
Iron plays a central role in key biological processes in both plants and animals. Lack of available iron commonly limits plant growth and nutritional value. Worldwide, dietary iron is primarily obtained from plant sources and, despite our best...
Breast -- Magnetic resonance imaging. Breast -- Tomography. Near infrared spectroscopy. Optical tomography. Imaging systems -- Design and construction. Diagnostic imaging -- Mathematical models.
We present new appearance editing algorithms that allow artists to perform complex editing operations on spatially-varying appearance datasets such as images and measured materials, in an intuitive and efficient manner. The goal is to develop...
We describe a set of natural image statistics that are built upon two multi-scale image decompositions, the quadrature mirror filter pyramid decomposition and the local angular harmonic decomposition. These image statistics consist of first- and...
Safety in transportation systems is a global concern with millions of road accidents happening worldwide every year. Despite sophisticated advancement in automotive design and accident serverity reduction technologies, traffic fatalities continue...