6,944 research outputs found

    Data registration and integration requirements for severe storms research

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    Severe storms research is characterized by temporal scales ranging from minutes (for thunderstorms and tornadoes) to hours (for hurricanes and extra-tropical cyclones). Spatial scales range from tens to hundreds of kilometers. Sources of observational data include a variety of ground based and satellite systems. Requirements for registration and intercomparison of data from these various sources are examined and the potential for operational forecasting application of techniques resulting from the research is discussed. The sensor characteristics and processing procedures relating to the overlay and integrated analysis of satellite and surface observations for severe storms research are reviewed

    Configuration description and load analysis for the Atmospheric and Oceanographic Information Processing System (AOIPS)

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    A computer system for processing image data is described. It essentially consists of two minicomputer systems. System components are listed and discussed, and flow charts are shown

    Atmospheric and Oceanographic Information Processing System (AOIPS) system description

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    The development of hardware and software for an interactive, minicomputer based processing and display system for atmospheric and oceanographic information extraction and image data analysis is described. The major applications of the system are discussed as well as enhancements planned for the future

    Reflectance Spectra of Titan Tholins at Cryogenic Temperatures and Implications for Compositional Interpretation of Red Objects in the Outer Solar System

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    We report the visual and near-infrared (0.4-2.5 micron) laboratory bi-directional reflectance of Titan tholin at cryogenic temperatures (approx. 100-300 K). When compared with room temperature measurements, the visual and near-infrared color of Titan tholin becomes slightly redder by approx. 5% at low temperatures in the 0.4-1.3 micron region. We estimate the influence of these colr changes on the interpretation of the Centaur Pholus and find that the modest color changes will not significantly alter existing interpretations

    Understanding the patterns, characteristics and trends in the housing sector labour force-AHURI Final Report No.208

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    The focus of this study is the national policy problem of the gap between housing supply and demand, as identified and monitored by the National Housing Supply Council. Research to date has not focused upon the spatial distribution of labour supply and demand of the housing sector labour force (HSLF). Also research to date has not distinguished between labour engaged in building new dwellings and labour engaged in undertaking alterations and additions. In addressing this research gap, this Final Report presents the summative output of the AHURI research project entitled: Understanding the patterns, characteristics and trends in the housing sector labour force in Australia. It follows the publication of the Positioning Paper for the project (Dalton et al. 2011a).This chapter has presented a response to the secondary research question: What are the temporal dimensions of the HSLF as a whole and the new build and alterations and additions sub-sectors? It first described the categories, containing records of workers who worked in the housing industry, which were used to interrogate the census data. Using these categories, the data presented showed that, in aggregate, the size of the HSLF grew in the period 2001-06. In Victoria, the workforce grew from 72 000 to 89 000, an increase of 23 per cent in the five-year period 2001-06. The 44 per cent growth in the Queensland workforce was almost twice that of Victoria for the same period when it grew from 53 000 to 77 000. This aggregate data was then split to distinguish between workers who worked on 'new build' housing and those who worked on 'alterations and additions'. The results of this splitting showed that there had been growth in both sub-sectors. The rate of growth in the alterations and additions sub-sector was greater than for the new build sector, although this growth was from a lower base

    Hierarchical clustering and formation of power-law correlation in 1-dimensional self-gravitating system

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    The process of formation of fractal structure in one-dimensional self-gravitating system is examined numerically. It is clarified that structures created in small spatial scale grow up to larger scale through clustering of clusters, and form power-law correlation.Comment: 9pages,4figure

    Positively charged amino acids are essential for electron transfer and protein-protein interactions in the soluble methane monooxygenase complex from methylococcus capsulatus (Bath)

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    The soluble methane monooxygenase (sMMO) complex from Methylococcus capsulatus (Bath) catalyses oxygen- and NAD(P)H-dependent oxygenation of methane, propene and other substrates. Whole-complex sMMO oxygenase activity requires all three sMMO components: the hydroxylase, the reductase and protein B. Also, in the presence of hydrogen peroxide, the hydroxylase alone catalyses substrate oxygenation via the peroxide shunt reaction. We investigated the effect of amine cross-linking on hydroxylase activity in order to probe the role of a gross conformational change that occurs in the hydroxylase upon binding of the other protein components. The cross-linker inhibited hydroxylase activity in the whole complex but this effect was due to covalent modification of primary amine groups rather than cross-linking. Covalent modification of arginine side-chains on the hydroxylase had a similar effect but, most remarkably, neither form of modification affected the activity of the hydroxylase via the peroxide shunt reaction. It was shown that covalent modification of positively charged groups on the hydroxylase, which occurred at multiple sites, interfered with its physical and functional interactions with protein B and with the passage of electrons from the reductase. These results indicate that protein B and the reductase of the sMMO complex interact via positively charged groups on the surface of the hydroxylase to induce a conformational change that is necessary for delivery of electrons into the active site of the hydroxylase. Modification of positively charged groups on protein B had no effect on its function, consistent with the hypothesis that positively charged groups on the hydroxylase interact with negative charges on protein B. Thus, we have discovered a means of specifically inactivating the interactions between the sMMO complex while preserving the catalytic activity of the hydroxylase active site which provides a new method of studying intercomponent interactions within sMMO.</p

    Operational Status of the International Space Station Plasma Contactor Hollow Cathode Assemblies July 2001 to May 2013

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    The International Space Station has onboard two Aerojet Rocketdyne developed plasma contactor units that perform the function of charge control. The plasma contactor units contain NASA Glenn Research Center developed hollow cathode assemblies. NASA Glenn Research Center monitors the on-orbit operation of the flight hollow cathode assemblies. As of May 31, 2013, HCA.001-F has been ignited and operated 123 times and has accumulated 8072 hours of operation, whereas, HCA.003-F has been ignited and operated 112 times and has accumulated 9664 hours of operation. Monitored hollow cathode ignition times and anode voltage magnitudes indicate that they continue to operate nominally

    Operational Status of the International Space Station Plasma Contactor Hollow Cathode Assemblies from July 2011 to May 2013

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    The International Space Station has onboard two Aerojet Rocketdyne developed plasma contactor units that perform the function of charge control. The plasma contactor units contain NASA Glenn Research Center developed hollow cathode assemblies. NASA Glenn Research Center monitors the onorbit operation of the flight hollow cathode assemblies. As of May 31, 2013, HCA.001-F has been ignited and operated 123 times and has accumulated 8072 hours of operation, whereas, HCA.003-F has been ignited and operated 112 times and has accumulated 9664 hours of operation. Monitored hollow cathode ignition times and anode voltage magnitudes indicate that they continue to operate nominally

    Theory of Pseudomodes in Quantum Optical Processes

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    This paper deals with non-Markovian behaviour in atomic systems coupled to a structured reservoir of quantum EM field modes, with particular relevance to atoms interacting with the field in high Q cavities or photonic band gap materials. In cases such as the former, we show that the pseudo mode theory for single quantum reservoir excitations can be obtained by applying the Fano diagonalisation method to a system in which the atomic transitions are coupled to a discrete set of (cavity) quasimodes, which in turn are coupled to a continuum set of (external) quasimodes with slowly varying coupling constants and continuum mode density. Each pseudomode can be identified with a discrete quasimode, which gives structure to the actual reservoir of true modes via the expressions for the equivalent atom-true mode coupling constants. The quasimode theory enables cases of multiple excitation of the reservoir to now be treated via Markovian master equations for the atom-discrete quasimode system. Applications of the theory to one, two and many discrete quasimodes are made. For a simple photonic band gap model, where the reservoir structure is associated with the true mode density rather than the coupling constants, the single quantum excitation case appears to be equivalent to a case with two discrete quasimodes
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