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Multiscale modeling and integration of physiological models carry challenges due to the complex nature of physiological processes. High coupling within and among scales present a significant challenge in constructing and integrating multiscale physiological models. In order to deal with such challenges in a systematic way, there is a significant need for an information technology framework together with related analytical and computational tools that will facilitate integration of models and simulations of complex biological systems. Physiological Model Simulation, Integration and Modeling Framework (Phy-SIM) is an information technology framework providing the tools to facilitate development, integration and simulation of integrated models of human physiology. Phy-SIM brings software level solutions to the challenges raised by the complex nature of physiological systems. The aim of Phy-SIM, and this paper is to lay some foundation with the new approaches such as information flow and modular representation of the physiological models. The ultimate goal is to enhance the development of both the models and the integration approaches of multiscale physiological processes and thus this paper focuses on the design approaches that would achieve such a goal. 相似文献
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The Tigris is one of the most important transboundary rivers in western Asia and originates in the Toros mountains of the Eastern Anatolia region of Turkey. Multivariate statistical techniques, such as cluster analysis (CA), principal component analysis (PCA) and factor analysis (FA), were applied for the evaluation of temporal/spatial variations and the interpretation of a water quality data set for the Tigris River, which was obtained during 1 year of monitoring. This study presents the usefulness of multivariate statistical techniques for the evaluation and interpretation of complex water quality data sets and apportionment of pollution sources/factors to obtain better information about water quality and the design of a monitoring network for the effective management of water resources. Hierarchical CA grouped 12 months into two periods (the first and second periods) and classified seven monitoring sites into three groups, that is, less polluted sites, medium polluted sites and highly polluted sites, based on similarities in the water quality characteristics. PCA/FA identified five factors in the data structure, which explained 77.5% of the total variance of the data set. This allowed us to group the selected parameters according to common features and to evaluate the influence of each group on the overall variation in water quality. Varifactors obtained from the factor analysis indicated that the parameters responsible for water quality variation were mainly related to soluble salts (natural), organic pollution and nutrients (anthropogenic). Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
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M. Jergel T. Melíšek H Allárová D. I. Belyj V. P. Kutepov A. J. Izrailev D. Synak J. Neuschl J. Ivan 《Journal of Materials Science》1982,17(6):1579-1584
The influence of the presence of oxygen in the Nb-Zr substrate upon some physical and mechanical properties of the Nb-ZrO2 substrate and/or Nb3Sn tape superconductor prepared from such a substrate has been studied. The results have shown that the Nb3Sn grains are much finer in the case of Nb-ZrO2, than those obtained on Nb-Zr substrate. As a result, both the electrical and mechanical properties have been substantially improved. The critical current at a field of 5 T increased by between 100 and 200 %, the alternating current losses decreased by about one order of magnitude, the tensile strength increased by about a factor of three and the microhardness value also increased by about a factor of three for oxygen contents in the range 0.03 to 0.70 wt%. The specific resistance of this substrate increased at the same time from 17 to 22 cm and the relative elongation decreased from 5 to 3 %. 相似文献
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Phase equilibrium relations in the V2O3-La2O3 system were investigated by X-ray powder diffraction and metallographic techniques. Binary mixtures, prepared from high-purity V2O3 and La2O3 powders, were equilibrated at 1600° C and then arc-melted under a partial pressure of argon. The specimens were heat-treated at various predetermined temperatures for prolonged periods and the phases present were identified by reflected-light microscopy and X-ray powder diffraction. The system consists of only one binary compound LaVO3. A eutectic between V2O3 and LaVO3 was established at 1750° C and 19 mol % La2O3 and also between LaVO3 and La2O3 at 1765° C and 75 moi % La2O3. No appreciable solid solubility was detected in the system. 相似文献
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Ayfer Sarac Dolunay Şakar Ozlem Cankurtaran Ferdane Yılmaz Karaman 《Polymer Bulletin》2005,53(5-6):349-357
Summary The retention diagrams of benzene, toluene, ethyl benzene, chloro benzene, n-propyl benzene, isopropyl benzene, methyl acetate, ethyl acetate, n-propyl acetate, n-butyl acetate and isoamyl acetate on the polycaprolactone were plotted at temperatures between 70 and 140oC by inverse gas chromatography technique. Percent crystallinity of polycaprolactone were obtained at temperatures below melting point from the retention diagrams of benzene, toluene and ethyl benzene. It was concluded that the data obtained by inverse gas chromatography were comparable those of obtained by differential scanning calorimetry. Specific retention volume, Vgo, Flory-Huggins polymer-solvent interaction parameters, 12, the weight fraction activity coefficients of the solvents at infinite dilution, 1, effective exchange energy parameters, Xeff were determined. Later, the partial molar heat of sorption, H1,sorp and the partial molar heat of mixing, H1 were obtained from the slope of the logarithm of specific retention volume, Ln Vgo versus 1/T plot and from the slope of the logarithm of the weight fraction activity coefficients, 1versus 1/T plot, respectively. 相似文献
100.
We have found experimentally that rf SQUID's working in a nonhysteretic mode with small critical currents give exactly at resonance and at very low rf bias a triangular pattern with a period equal to half of one elementary quantum of magnetic flux. We discuss a possible explanation of this peculiar result. 相似文献