14,241 research outputs found

    Remote sensing X-ray spectrometer

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    Spectrometer measures chemical composition of lunar rocks by remote sensing from orbit and senses lunar X-rays produced by interaction of solar X-rays and elements on the lunar surface. Instrument features high sensitivity, data handling system that accumulates and prepares data for telemetry, and automatic calibration

    Comment about pion electro-production and the axial form factors

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    The claim by Haberzettl (Phys.Rev.Lett.85 (2000) 3576) that the axial form factor of the nucleon cannot be accessed through threshold pion electroproduction is unfounded

    Seasonal Emergence Patterns of Black Flies (Diptera: Simuliidae) in Northwestern Pennsylvania

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    A two-year emergence trap study of black flies at four sites in northwestern Pennsylvania yielded 1%3 individuals of nine species. The collections included Prosimulium mixtum, P. jU5cum, Stegapterna mutata, Simulium aureum, S. excisum (recorded for the first time from Pennsylvania), S. gauldingi, S. sp. nr. innacens, S. vittatum, and S. tuberasum. Species richness for all sites peaked during May. Emergence collections below a sewage plant effluent outfall represented fewer individuals and species than collections above the effluent outfall. Chromosomal analysis of supplementary larval collections revealed the IIIL-l and IS-7 sibling species of S. vittatum and the FG sibling of S. tuberasum

    An Energy-Minimization Finite-Element Approach for the Frank-Oseen Model of Nematic Liquid Crystals: Continuum and Discrete Analysis

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    This paper outlines an energy-minimization finite-element approach to the computational modeling of equilibrium configurations for nematic liquid crystals under free elastic effects. The method targets minimization of the system free energy based on the Frank-Oseen free-energy model. Solutions to the intermediate discretized free elastic linearizations are shown to exist generally and are unique under certain assumptions. This requires proving continuity, coercivity, and weak coercivity for the accompanying appropriate bilinear forms within a mixed finite-element framework. Error analysis demonstrates that the method constitutes a convergent scheme. Numerical experiments are performed for problems with a range of physical parameters as well as simple and patterned boundary conditions. The resulting algorithm accurately handles heterogeneous constant coefficients and effectively resolves configurations resulting from complicated boundary conditions relevant in ongoing research.Comment: 31 pages, 3 figures, 3 table

    High Temperature Expansion Study of the Nishimori multicritical Point in Two and Four Dimensions

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    We study the two and four dimensional Nishimori multicritical point via high temperature expansions for the ±J\pm J distribution, random-bond, Ising model. In 2d2d we estimate the the critical exponents along the Nishimori line to be γ=2.37±0.05\gamma=2.37\pm 0.05, ν=1.32±0.08\nu=1.32\pm 0.08. These, and earlier 3d3d estimates γ=1.80±0.15\gamma =1.80\pm 0.15, ν=0.85±0.08\nu=0.85\pm 0.08 are remarkably close to the critical exponents for percolation, which are known to be γ=43/18\gamma=43/18, ν=4/3\nu=4/3 in d=2d=2 and γ=1.805±0.02\gamma=1.805\pm0.02 and ν=0.875±0.008\nu=0.875\pm 0.008 in d=3d=3. However, the estimated 4d4d Nishimori exponents γ=1.80±0.15\gamma=1.80\pm 0.15, ν=1.0±0.1\nu=1.0\pm 0.1, are quite distinct from the 4d4d percolation results γ=1.435±0.015\gamma=1.435\pm 0.015, ν=0.678±0.05\nu=0.678\pm 0.05.Comment: 5 pages, RevTex, 3 postscript files; To appear in Physical Review

    Introduction, Sypmosium Common Law Environmental Protection

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    Is the common law a viable means of addressing environmental problems? The first wave of environmental common law scholarship, together with the law and economics and classical liberal literatures, at least put the issue on the table for discussion. The response from the critics raised some important criticisms, ones that needed to be answered. Whatever the failings of the environmental regulatory state, the common law has failings of its own, including the failure to protect many ecological resources in the period before the enactment of federal environmental law. In some instances administrative regulation may have hampered or sabotaged common law protections, but in others the common law failed on its own. With the generous support of the Roe Foundation for the Property and Environment Research Center, we sought to expand the literature beyond the first round of discussion and to prompt a serious look at the common law\u27s potential, and potential weaknesses, in addressing environmental problems. We wanted to know where the case for the common law stood. The result is the set of articles and comments by the impressive group of authors included in this symposium
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