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991.
We have developed a three-dimensional toroidal gyrokinetic particle simulation to study tokamak turbulence. The gyrokinetic equations are a reduced set derived from the Vlasov-Maxwell equations by phase averaging over the ion gyromotion and keeping only the time and space scales relevant for describing tokamak plasmas. These large-scale simulations in complex geometry can produce gigabytes of data consisting of large 3D arrays evolving in time. Visualization plays a critical role in going from the raw nonlinear solution of these complex equations to a simplified theoretical model explaining the essential underlying physics  相似文献   
992.
Skeletal muscle glycogen synthase (encoded by GYS1 on chromosome 19q13.3) is the rate-limiting enzyme in insulin-mediated non-oxidative glucose disposal. Our previous studies have demonstrated an impairment of insulin-stimulated GYS1 activities in insulin-resistant Pima Indians, and associations of non-insulin-dependent diabetes mellitus (NIDDM) with the GYS1 locus were reported recently in Finnish and Japanese populations. We have performed linkage and association analyses of GYS1 and seven additional DNA markers on 19q with NIDDM, and with parameters of insulin action in the Pima Indians. We have found a significant association of NIDDM with GYS1 genotypes (p = 0.009), and with common GYS1 alleles (p = 0.022) in the Pima Indians. We have performed a detailed comparative analysis of the GYS1 gene, mRNA, and protein product in insulin-sensitive and insulin-resistant Pima Indians. No mutations in GYS1 coding sequences were detected; nor did we find alterations of GYS1 mRNA expression or of its basal enzymatic activity in insulin-resistant Pima Indians. These results contrasted with a 25% reduction of immunoreactive protein in insulin-resistant subjects as detected by Western blotting with an antibody specific for the C-terminal end of GYS1 (t-test p = 0.024; Wilcoxon's rank-sum test, p = 0.04). Because no mutations were detected in the DNA encoding this epitope, the difference in immunoreactivity may reflect post-translational modification(s) of the protein rather than a difference in the gene itself, or it could have occurred by chance. We conclude that our data do not indicate alterations in the GYS1 gene as the cause for the observed association, and that a different locus near GYS1 may be the contributing genetic element.  相似文献   
993.
The Santa Amalia building in Barcelona is a block of six flats incorporating a duct by which ligth is sent to the kitchens - previously without natural ligthing- and also allows natural ventilation. Moreover, the passive solar gains obtained from the extensive glazed surfaces and the conservation of internal heat gains, along with a high degree of isulation, give energy saving of 68% for heating.  相似文献   
994.
Summary The Polymer Section of the Santa Barbara Workshop on Modeling of Materials is briefly reviewed. Motivation and need for modeling in polymer-based materials are outlined and the recommendations resulting from the workshop reported.  相似文献   
995.
996.
997.
The accuracy and efficiency of the self-consistent (regarding the electric field) Monte Carlo model, nonself-consistent Monte Carlo model, and the soft-threshold lucky electron model (LEM) for the calculation of substrate currents in deep sub-μm n-MOSFET's are investigated. While the two Monte Carlo models are in good agreement with the experiment, the simpler LEM model still gives reasonable results even for a 0.16 μm n-MOSFET. On the other hand, huge differences in the CPU time consumption are found and the LEM is about four orders of magnitude faster than the self-consistent Monte Carlo simulations. The nonself-consistent calculations are only one order of magnitude slower than the LEM. The good agreement with the experiment is obtained without considering the so-called surface impact ionization or any fitting of parameters on the device level  相似文献   
998.
999.
On the Evolutionary Optimization of Many Conflicting Objectives   总被引:2,自引:0,他引:2  
This study explores the utility of multiobjective evolutionary algorithms (using standard Pareto ranking and diversity-promoting selection mechanisms) for solving optimization tasks with many conflicting objectives. Optimizer behavior is assessed for a grid of mutation and recombination operator configurations. Performance maps are obtained for the dual aims of proximity to, and distribution across, the optimal tradeoff surface. Performance sweet-spots for both variation operators are observed to contract as the number of objectives is increased. Classical settings for recombination are shown to be suitable for small numbers of objectives but correspond to very poor performance for higher numbers of objectives, even when large population sizes are used. Explanations for this behavior are offered via the concepts of dominance resistance and active diversity promotion.  相似文献   
1000.
The results of investigations performed by specialists at Research and Design Institute of Electrical Technology together with other enterprises, institutes, and organizations concerning the formulation of a strategy for the development of nuclear power in Russia in the first half of the 21st century are presented. The individual stages of the work, key assumptions, ideas, and recommendations, on which the strategy is based, the initiatives which the President of the Russian Federation advanced at the millennium summit held at the United Nations, and the international INPRO project initiated by Russia are examined. It is concluded that innovative development and a transition to building as quickly as possible nuclear power objects that meet the requirements and demands of the new century are necessary. __________ Translated from Atomnaya énergiya,Vol. 103, No. 1, pp. 5–15, July, 2007.  相似文献   
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