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...
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...
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....
The accelerated expansion of space in the Universe has been known for two decades. However, finding a plausible theory that describes this expansion is more difficult: Taking general relativity for granted requires us to stipulate the existence of...
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...
Digital cinematography. ; Cinematography -- Lighting -- Data processing -- Evaluation. ; Cinematography -- Special effects -- Data processing -- Evaluation. ; User interfaces (Computer systems) -- Evaluation.
We define appearance design as the creation and editing of scene content such as lighting and surface materials in computer graphics. The appearance design process takes a significant amount of time relative to other production tasks and poses...
Structural control (Engineering). ; Smart structures -- Vibration. ; Strains and stresses -- Computer simulation. ; Automatic control -- Sensitivity. ; Feedback control systems.
This thesis investigates vibration-based damage identification problems in smart structures. Vibration-based damage metrics suffer from small sensitivity of modal properties to damage, thus making it difficult to detect, locate, and determine the...
Second harmonic generation. ; Second harmonic generation -- Mathematical models. ; Glass -- Effect of infrared radiation on. ; Glass -- Electric properties.
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...
Continual improvements to clinical breast imaging technologies have led to ever earlier detections and increasingly accurate localizations of female breast cancers. While these advancements have certainly improved the prognoses of many patients,...
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...
Opinion dynamics is a complex procedure that entails a cognitive process when it deals with how a person integrates influential opinions to form revised opinion. Early research on opinion formation and social influence can be traced back to the...
In this thesis, we characterize and enumerate the permutations which are realized by the orbits of signed shifts, a family of discrete dynamical systems on words. The permutations, which are called patterns of the signed shifts, are given by the...
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....
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...
In the past decade, the use of ordinal patterns in the analysis of time series and dynamical systems has become an important tool. Ordinal patterns (otherwise known as a permutation patterns) are found in time series by taking n data points at...
Multimodality imaging is becoming the standard of care for research and clinical studies. Such an approach is able to provide complementary information which can detect and characterize tumors. Advancing instrumentation for diffuse near-infrared...
Arctic soils in the permafrost region store substantially more carbon than is contained in the atmosphere, and are undergoing rapid change associated with anthropogenic climate change. Soil decomposition is an important component of ecosystem...
We provide a theoretical model for a design involving a dc voltage biased Josephson junction (JJ) that strongly drives a high quality factor microwave cavity via the ac Josephson effect. We explore the rich classical dynamics of the resultant...
The performance of machine learning algorithms largely depends on data representation. As a critical step in machine learning, representation learning (feature learning) learns a transformation of training data to give a new representation that can...
Si-based quantum devices, including Si/SiGe quantum dots (QD), are promising candidates for spin-based quantum bits (quits), which are a potential platform for quantum information processing [1]. Meanwhile, qubit readout remains a challenging task...
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...
Interleukin-2 (IL-2) is an immunoregulatory cytokine whose biological effects are mediated through interaction with specific receptors (IL-2R) on the surface of target cells. Due to its presumed role in generating a normal immune response, IL-2 is...
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...
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...
The thesis is devoted to the effects of electromagnetic coupling between the Earth's magnetosphere and the active auroral ionosphere. The research has been focused, in particular, on the concept of ionospheric feedback instability. The feedback...
Magnetic resonance. ; Microwaves -- Physiological effect. ; Thermoelasticity. ; Neutron spin echoes. ; Microwave imaging in medicine. ; Imaging systems in medicine -- Design. ; Breast -- Magnetic resonance imaging.
Magnetic Resonance has been shown to detect tissue displacements generated by a mechanical stimulus or an ultrasound (US) field. Magnetic Resonance Microwave Absorption (MRMA) imaging uses MR to image microwave-induced thermoelastic waves as a...
Two localized spectroscopic imaging methods were investigated to detect and discriminate microscopic pathologies at the surface of excised breast tissues in order to improve resection completeness during breast conserving surgery. A scanning in...