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....
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...
As the visual effect and movie industries are striving for realism and high fidelity images, physically based lighting, global illumination, realistic materials, and highly tessellated geometry are gradually accepted and used in movie and game...
We begin with a result on the refocussing of null geodesics in space-times. We show that all oriented refocussing 2-dimensional Lorentz manifolds are also strongly refocussing. We also introduce a theory of virtual Legendrian knots. We show that...
In Chapter 2 we look at the distribution of permutation statistics in the context of pattern-avoiding permutations. The first part of this chapter deals with a recursively defined bijection of Robertson [37] between 123- and 132-avoiding...
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...
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....
For ordinary knots in R 3 , there are no degree one Vassiliev invariants. For virtual knots, however, the space of degree one Vassiliev invariants is infinite dimensional. We introduce a sequence of three degree one Vassiliev invariants of virtual...
There are no Vassiliev invariants of degree one for classical knots. A. Henrich proved the existence of a sequence of three Vassiliev invariants of degree one for virtual knots. The invariants get stronger and stronger, and the final invariant is...
'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...
This thesis is divided into 2 parts. In the first part of the thesis, we describe a software based approach to speeding up the Magnetic Resonance Imaging modality. In the second part of the thesis, we describe Significance Tree Quantization, which...
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...
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...
We present results from a modeling effort of simple shock phenomena in the Cygnus Loop and Cassiopeia A. Using multi-epoch MDM observations of a small, isolated cloud in the southwest region of the Cygnus Loop, we measure the velocity of the...
Robots -- Control systems. ; Robots -- Motion. ; Computer algorithms. ; Electronic data processing -- Distributed processing.
Self-reconfiguring robots are robots composed of many physically connected modules which can change their structural configuration to support multiple functionalities. We claim that self-reconfiguring robots are more versatile, extensible, and...
In an undercooled environment any protuberance or bump on a planar solid/liquid interface that extends into the melt enhances its growth since the surrounding temperature gradient is greater than that about the planar surface. Consequently, the...
Space plasmas. ; Magnetopause. ; Solar wind. ; Magnetic flux. ; Plasma astrophysics.
Two types of two-dimensional (2-D), coherent (time-stationary) space plasma structures, described by one-fluid, magnetostatic and isotropic plasma theory, are examined. One is the internal structure of the Earth's magnetopause and the other is...
Riemannian manifolds. Singularities (Mathematics). Laplacian operator. Spectral theory (Mathematics). Riemann surfaces. Curves on surfaces. Geometry
Historically, inverse spectral theory has been concerned with the relationship between the geometry and the spectrum of compact Riemannian manifolds, where spectrum means the eigenvalue spectrum of the Laplace operator as it acts on smooth...
Macrocyclic tetrapyrroles are essential to life. In nature, they play important roles in living organisms, such as oxygen transportation and photosynthesis. Pentynoic acids are versatile precursors for preparing pyrrolines and higher homologues....
For a long-lived metastable system, the decay of the survival probability is typically exponential. However, deviations are known to exist at short times (the quantum Zeno effect) and at long times (algebraic tails in classical hydrodynamic...
Manifolds (Mathematics) Geodesics (Mathematics) Space and time.
We investigate weak and strong refocusing of light rays in a space-time and related concepts. A strongly causal space-time ( X^ n +1 , g ) is emphstrongly refocusing at x ∈ X if there is a point y ≠ x such that all null-geodesics through y pass...