1,581 research outputs found

    Collision Integrals for the Exponential Attractive Potential

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    Numerical integration calculation of collision integrals for exponential attractive potential of gase

    Hyper-Raman scattering analysis of the vibrations in vitreous boron oxide

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    Hyper-Raman scattering has been measured on vitreous boron oxide, v−v-B2_2O3_3. This spectroscopy, complemented with Raman scattering and infrared absorption, reveals the full set of vibrations that can be observed with light. A mode analysis is performed based on the local D3h_{3h} symmetry of BO3_3 triangles and B3_3O3_3 boroxol rings. The results show that in v−v-B2_2O3_3 the main spectral components can be succesfully assigned using this relatively simple model. In particular, it can be shown that the hyper-Raman boson peak arises from external modes that correspond mainly to librational motions of rigid boroxol rings.Comment: 13 pages, 11 figures, 2 table

    Inverse monoids and immersions of 2-complexes

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    It is well known that under mild conditions on a connected topological space X\mathcal X, connected covers of X\mathcal X may be classified via conjugacy classes of subgroups of the fundamental group of X\mathcal X. In this paper, we extend these results to the study of immersions into 2-dimensional CW-complexes. An immersion f:D→Cf : {\mathcal D} \rightarrow \mathcal C between CW-complexes is a cellular map such that each point y∈Dy \in {\mathcal D} has a neighborhood UU that is mapped homeomorphically onto f(U)f(U) by ff. In order to classify immersions into a 2-dimensional CW-complex C\mathcal C, we need to replace the fundamental group of C\mathcal C by an appropriate inverse monoid. We show how conjugacy classes of the closed inverse submonoids of this inverse monoid may be used to classify connected immersions into the complex

    Gabriel T. Csanady : understanding the physics of the ocean

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    Author Posting. © Elsevier B.V., 2006. This is the author's version of the work. It is posted here by permission of Elsevier B.V. for personal use, not for redistribution. The definitive version was published in Progress In Oceanography 70 (2006): 91-112, doi:10.1016/j.pocean.2006.07.002.Gabriel T. Csanady turned 80 in December 2005 and we celebrate it with this special Progress in Oceanography issue. It comprises 20 papers covering some of the many areas that Gabe contributed significantly throughout his professional career. In this introductory paper we briefly review Gabe’s career as an engineer, meteorologist and oceanographer, and highlight some of his major contributions to oceanography, both as a scientist as well as an educator. But we also use this opportunity to remember and thank Gabe, and his wife Joyce, for being such good friends and mentors to several generations of oceanographers. The authors of the collection of papers in this volume deserve special thanks for their efforts. We also are pleased to acknowledge the support of Progress in Oceanography’s editor, Detlef Quadfasel, and the many anonymous reviewers who generously contributed their time and expertise

    Predictors of placement from a juvenile detention facility

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    The purpose of this project was to determine whether certain personal, socioeconomic, and court-related factors are significantly related to the differential placement of delinquent and dependent children from the detention facility at the Donald E. Long Home. A stratified random sample was composed of 173 placements of children who were held in detention after a preliminary hearing. The review of literature revealed that little systematic. Information is known regarding the placement process as it is related to differential placement of children from a detention facility. A code sheet was developed for recording the information in the children’s records maintained by the court. Fourteen variables were ultimately selected for analysis of their relationship to differential placement. These variables were subjected to three statistical approaches; a descriptive analysis of the random sample, testing of the significance of each variable to the alternatives in placement by either Chi square or analyses of variance, and testing of several variables in combination by discriminant function. This study was limited by the fact that only demographic variables were tested. Although three individual variables were found to have a high degree of significance in relation to placement, the data as produced within the scope of this research project does not provide an effective placement profile. The need for additional research in the area of the differential placement process is clearly indicated. Suggestions are made for future research

    Spectroscopy of Quasar Candidates from SDSS Commissioning Data

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    The Sloan Digital Sky Survey has obtained images in five broad-band colors for several hundred square degrees. We present color-color diagrams for stellar objects, and demonstrate that quasars are easily distinguished from stars by their distinctive colors. Follow-up spectroscopy in less than ten nights of telescope time has yielded 22 new quasars, 9 of them at z>3.65z> 3.65, and one with z=4.75z = 4.75, the second highest-redshift quasar yet known. Roughly 80% of the high-redshift quasar candidates selected by color indeed turn out to be high-redshift quasars.Comment: 4 pages, 3 figures, to appear in the proceedings of "After the Dark Ages: When Galaxies were Young (the Universe at 2<z<5)", 9th Annual October Astrophysics Conference in Marylan
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