1,330 research outputs found
Parabolic bundles and representations of the fundamental group
Let X be as smooth complex projective variety with Neron-Severi group
isomorphic to Z, and D an irreducible divisor with normal crossing
singularities. Assume r is equal to 2 or 3. We prove that if the fundamental
group of X doesn't have irreducible PU(r) representations, then the fundamental
group of X-D doesn't have irreducible U(r) representations. The proof uses the
non-existence of certain stable parabolic bundles. We also obtain a similar
result for GL(2) when D is smooth and X is a complex surface.Comment: 13 pages, 1 figure, LaTeX2
Probabilistic Models for Droughts: Applications in Trigger Identification, Predictor Selection and Index Development
The current practice of drought declaration (US Drought Monitor) provides a hard classification of droughts using various hydrologic variables. However, this method does not yield model uncertainty, and is very limited for forecasting upcoming droughts. The primary goal of this thesis is to develop and implement methods that incorporate uncertainty estimation into drought characterization, thereby enabling more informed and better decision making by water users and managers. Probabilistic models using hydrologic variables are developed, yielding new insights into drought characterization enabling fundamental applications in droughts
A rapid method for the computation of equilibrium chemical composition of air to 15000 K
A rapid computational method has been developed to determine the chemical composition of equilibrium air to 15000 K. Eleven chemically reacting species, i.e., O2, N2, O, NO, N, NO+, e-, N+, O+, Ar, and Ar+ are included. The method involves combining algebraically seven nonlinear equilibrium equations and four linear elemental mass balance and charge neutrality equations. Computational speeds for determining the equilibrium chemical composition are significantly faster than the often used free energy minimization procedure. Data are also included from which the thermodynamic properties of air can be computed. A listing of the computer program together with a set of sample results are included
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