In 1958 Lax conjectured that hyperbolic polynomials in three variables are determinants of linear combinations of three symmetric matrices. This conjecture is equivalent to a recent observation of Helton and Vinnikov. A homogeneous polynomial p on R n is hyperbolic with respect to a vector e ∈ R n if p(e) = 0 and, for all vectors w ∈ R n , the univariate polynomial t → p(w − te) has all real ro...

Experimental and Theoretical Studies of a Gadolinium-Water Neutron Detector for Cosmogenic Neutron Flux Measurements by Robert K. Lanza, Jr. Bachelors of Science in Physics University of California, Santa Barbara Harry N. Nelson, Advisor This work describes experimental and theoretical aspects of calibrations performed on a gadolinium/water neutron detector designed to measure the cosmogenic ne...

Let M be an n-dimensional complete simply connected Riemannian manifold with sectional curvature bounded above by a nonpositive constant −κ2. Using the cone total curvature TC(Γ) of a graph Γ which was introduced by Gulliver and Yamada [8], we prove that the density at any point of a soap film-like surface Σ spanning a graph Γ ⊂ M is less than or equal to 1 2π {TC(Γ)− κArea(p×Γ)}. From this den...

An application area of vertex enumeration problem (VEP) is the usage within objective space based linear/convex vector optimization algorithms whose aim to generate (an approximation of) Pareto frontier. In such algorithms, VEP, which defined in space, solved each iteration and it has a special structure. Namely, recession cone polyhedron be generated ordering cone. We consider give detailed de...

Assessing the condition of the alveolar bone before and after orthodontic treatment is important. Recently, cone-beam computed tomography has been widely accepted as a useful tool for orthodontic treatment. Moreover, using a three-dimensional (3D) structural analysis software enables gathering detailed information and quantifying data. The aim of this study was to introduce various quantitative...

A semi-distributed watershed model was developed that conceptualizes the catchment as a cascade of nonlinear storage elements whose geometric dimensions are derived from the Horton±Strahler ordering of the stream network. Each storage element represents quick storm runo€ over land or in a channel segment. The physically based groundwater submodel is parameterized through the application of the ...

This paper attempts to test the morale theory of nominal wage rigidity by identifying the causal effect of pay cuts on workers’ income satisfaction and work morale. This paper uses the current deflationary recession in Japan to estimate this causal effect. Our original survey of Japanese firms and their employees conducted in 2000 revealed that about 17 percent of our sample experienced a nomin...

We present results of a search for galaxies around the highly obscured giant radio galaxy PKS1343– 601 using the near-infrared DENIS survey. We compare our findings with surveys in the B-band, at the 21 cm line emission, and with 2MASS. Recession velocities of galaxies in this area suggest a low-velocity-dispersion group or cluster of galaxies including an X-ray confirmed Seyfert 2. The colours...

In all Friedman models, the cosmological redshift is widely interpreted as a consequence of the general-relativistic phenomenon of expansion of space. Other commonly believed consequences of this phenomenon are superluminal recession velocities of distant galaxies, and the distance to the particle horizon greater than c t (where t is the age of the Universe), in apparent conflict with special r...

We check the validity of the widely used classical apsidal motion formula as a function of orbital parameters, stellar structure, and stellar rotation rate by comparing dynamical calculations of the periastron advance with the static tidal formula. We nd that the classical formula gives very accurate results when the periods of the low order quadrupole g, f and p modes are smaller than the peri...