1,083 research outputs found

    Neutron spectral measurements in the upper atmosphere

    Get PDF
    An experiment to measure neutrons in the upper atmosphere was performed on a balloon flight from Palestine, Texas, at an altitude of about 32 km. The experimental arrangement is discussed briefly, and results of a preliminary analysis of the data for neutrons in the energy range 3 to 30 MeV are given

    Topic Maps For Improving Services In Disaster Operations Management

    Get PDF
    Disaster operations management is an increasingly important application area for the developing techniques of service science. This paper examines the use of topic maps, a semantic technology, within this environment, and provides a preliminary discussion of the benefits that its implementation can provide in the capture and exchange of contextual information. The discussion is motivated by a look at the different phases of disaster operations management in a services context, and focuses on the need for effective and relevant information exchange as an important part of the services process. As the amount and complexity of information increases within such processes, semantic technologies are becoming increasingly important as a means representing and managing contextual information. This paper seeks to help further the understanding of the relevance of such tools as part of the study of service science

    USING INTERACTION IN TWO-WAY DATA TABLES

    Get PDF
    Agronomists and breeders frequently collect yield data for a number of genotypes in a number of environments (site-years), resulting in a two-way data table. The Additive Main effects and Multiplicative Interaction (AMMI) model combines regular analysis of variance (ANOVA) for additive main effects with principal components analysis (PCA) for multiplicative structure within the interaction (that is, within the residual from ANOVA). AMMI is effective for (1) understanding genotype-environment interaction, (2) improving the accuracy of yield estimates, (3) increasing the probability of successfully selecting genotypes with the highest yields, (4) imputing missing data, and (5) increasing the flexibility and efficiency of experimental designs. Ultimately these advantages imply larger selection gains in breeding research and more reliable recommendations in agronomy research. AMMI is ordinarily the statistical method of choice when main effects and interaction are both important

    Temperature dependence of the response of lithium-drifted germanium detectors to gamma rays

    Get PDF
    Temperature dependence of lithium-drifted germanium detector response to gamma radiatio

    Lateral Control by Spoilers at the DVL

    Get PDF
    The present report describes the development of spoiler control at the DVL from the end of 1936 until the beginning of 1939. The authors are fully aware that the present report also forms only a contribution to the problem of spoiler control and offers at best a possibility of extrapolation regarding the behavior of the control in modern airplanes. A modern airplane (Me 109) is being reconstructed for conversion to spoiler control. Experience has shown, however, that the construction and testing of such a model requires at least a year. Thus it seems appropriate to report summarily now in order to keep the understanding and cooperation of the interested departments aroused. The following reports are only a section of a long development partly evolved abroad

    Diethyl 2,5-bis­[(1E)-(1H-pyrrol-2-yl­methyl­idene)amino]­thio­phene-3,4-dicarboxyl­ate

    Get PDF
    In the crystal structure of the title compound, C20H20N4O4S, the azomethine group adopt E conformations. The pyrrole units are twisted by 10.31 (4) and 18.90 (5)° with respect to the central thio­phene ring. The three-dimensional network is close packed and involves N—H⋯O, N—H⋯N, C—H⋯N and C—H⋯O hydrogen bonding

    Evaluation of Cathode Gas Composition and Temperature Influences on Alkaline Anion Exchange Membrane Fuel Cell (AAEMFC) Performance

    Full text link
    The effects of different temperatures (55, 65, 75 and 85 °C) and cathode gas compositions (O2, synthetic air, air and 90% synthetic air+10% CO2) on alkaline anion exchange membrane fuel cell (AAEMFC) were evaluated. Membrane electrode assemblies (MEA) were fabricated using commercial anion exchange membrane (AEM) in OH- form and Pt catalyst. Polarization curves and voltage responses during constant current were performed in order to describe the influences of temperature and gas composition on the AAEMFC performance. The experimental results showed that the fuel cell performance increases with elevating temperatures for all applied gas compositions. Highest power density of 34.7 mW cm-2 was achieved for pure O2 as cathode feed. A decrease to 20.3 mW cm-2 was observed when cathode gas composition was changed to synthetic air due to reduction of the O2 partial pressure. The presence of CO2 in atmospheric air applied to the cathode stream caused a further drop of the maximum power density to 15.2 mW cm-2 driven by neutralization of OH- ions with CO2

    The spin state transition in LaCoO3_{3}; revising a revision

    Get PDF
    Using soft x-ray absorption spectroscopy and magnetic circular dichroism at the Co-L2,3L_{2,3} edge we reveal that the spin state transition in LaCoO3_{3} can be well described by a low-spin ground state and a triply-degenerate high-spin first excited state. From the temperature dependence of the spectral lineshapes we find that LaCoO3_{3} at finite temperatures is an inhomogeneous mixed-spin-state system. Crucial is that the magnetic circular dichroism signal in the paramagnetic state carries a large orbital momentum. This directly shows that the currently accepted low-/intermediate-spin picture is at variance. Parameters derived from these spectroscopies fully explain existing magnetic susceptibility, electron spin resonance and inelastic neutron data

    REVIEW OF THE ORR SHIELD FOR 30-Mw OPERATION

    Get PDF
    • …
    corecore