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881.
This paper develops a transient thermal model for line traps. The model was incorporated into a computer program that numerically integrates the governing nonlinear differential equation in time to predict critical temperatures and component short and long term ratings for a wide range of operating conditions. The model accounts for many factors including: variable air properties, variable material properties, environmental conditions, and a wide variety of component geometries and orientations. To verify the temperatures predicted by the thermal model, The Georgia Power Research Center carried out an extensive series of indoor laboratory tests to experimentally measure temperatures of energized line traps under transient loading conditions. Model predictions were within 8°C for 75 percent of the data. This paper presents the development of the governing equations and describes in detail the calculation of the convective and radiative components of heat transfer. Comparisons of the model predictions for two different line trap designs in different orientations to experimental data are presented to demonstrate the accuracy and flexibility of the thermal model 相似文献
882.
AMD engineers developed the K5 microarchitecture for AMD's first home grown x86-compatible microprocessor. We designed it to not only compete with Intel Pentium-class processors but, more importantly, to establish a baseline microarchitecture and implementation for ongoing development of a family of leading-edge x86-compatible microprocessors. The resulting AMD5K86 products can decode and issue up to four x86 instructions per cycle, with full out-of-order dependency-driven execution that takes place speculatively beyond unresolved branches. As a first-time, independent x86 implementation, the K5 microprocessor presented many unique challenges and constraints to its designers 相似文献
883.
Research in object-oriented manufacturing simulations:an assessment of the state of the art 总被引:1,自引:0,他引:1
S. Narayanan D.A. Bodner T. Govindaraj L.F. Mcginnis C.M. Mitchell U. Sreekanth 《IIE Transactions》1998,30(9):795-810
Object-oriented programming (OOP) has been revolutionizing software development and maintenance. When applied to simulation of manufacturing systems, OOP also provides an opportunity for developing new ways of thinking and modeling. In this paper, we identify existing large-scale, persistent OOP-based research efforts focusing on manufacturing system simulation, and present an integrating framework for discussing the associated modeling abstractions, implementation strategies, common themes, and distinctive features. The goal is to identify the fundamental research and application issues, assess the current state of the art, and identify key research needs. 相似文献
884.
Zaleski A. Sinha S.P. Ioannou D.E. Campisi G.J. Hughes H.L. 《Electron Devices, IEEE Transactions on》1995,42(9):1697-1700
By operating one channel of a typical SOI MOSFET in avalanche while keeping the opposite channel accumulated, charge injection into the opposite gate takes place. Three independent experiments are described that demonstrate the occurrence of this opposite-channel based charge injection. The experimental results are in agreement with PISCES numerical simulations 相似文献
885.
886.
Serendipitous events have been shown to affect the careers of prominent counseling psychologists. Why should this seem surprising? Unplanned events affect everyone's career. The surprise is due to the widespread but unfounded assumption that career decisions should be the logical outcome of a "true reasoning" process. Counseling psychologists need to (a) broaden their view so that the reluctance to make an occupational commitment in the face of unpredictable future events can be celebrated as open-mindedness, not denigrated as indecisiveness, (b) teach clients that unplanned events are a normal and expected part of the career development process, and (c) teach clients how to generate unplanned events that contribute to a more satisfying life. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
887.
PM Warnecke D Biniszkiewicz R Jaenisch M Frommer SJ Clark 《Canadian Metallurgical Quarterly》1998,22(2):111-121
Currently, the pig species is regarded as the most likely organ donor for human xenotransplantation in the future. However, it cannot be granted that the pig will be the optimal species of choice. We have studied human anti-sheep antibodies in comparison with anti-pig antibodies. The anti-sheep lymphocytotoxic and hemagglutination titers were in the range 8 to 128 and 2 to 32, respectively, in single individuals, which were considerably lower than the anti-pig titers of these individuals. Perfusion of sheep kidneys with human blood reduced the anti-sheep xenoantibody titers to zero as measured by lymphocytotoxic, hemagglutination, and sheep aortic endothelial cell antibody binding assays. The perfused kidneys showed generalised depositions of human IgM and C3c in the vascular tree and focal depositions of C1q and fibrin. Obliteration of capillaries by human platelets and polymorphonuclear cells were observed. Total neutral glycolipid fractions were isolated from sheep intestinal, pancreatic, and kidney tissues. By using a chromatogram binding assay, a monoclonal anti-Forssman antibody identified a single compound with five sugar residues in all organs. Several glycolipid bands were stained in all organs by the Gal(alpha)1-specific lectin I-B4 from Griffonia (Bandeiraea) Simplicifolia. A human AB serum pool showed staining by both IgG and IgM antibodies of the Forssman and Gal(alpha)1-terminating components as well as some other, not structurally identified, components. The Forssman and Gal(alpha)1-reactivity in human sera could be eliminated by immunoadsorption using Forssman and Gal(alpha)1-3Gal-immunoadsorbent columns, respectively. Immunostaining of sheep kidney tissue sections showed the presence of Gal(alpha)1-terminating epitopes by immunoperoxidase and immunogold silver staining techniques. Proximal convoluted tubules showed a strong staining, while thin loops of Henle, collecting ducts, urothelium, and vessels showed a weaker staining. Distal convoluted tubules and thick loops of Henle were completely negative. In summary, human serum contains anti-sheep xenoantibodies reacting mainly with the Forssman and Gal(alpha)1-determinants in sheep tissues and the anti-sheep antibody titers are lower than the corresponding anti-pig titers. 相似文献
888.
889.
L. A. Babkina M. I. Prokopenko V. L. Zinchenko N. A. Stepanyuk V. V. Topchii A. D. Gorbunov L. N. Alekhina 《Refractories and Industrial Ceramics》1996,37(1-2):27-28
Materials proposed for the production of a high-alumina mortar are investigated, namely, waste of melting of secondary aluminum, polishing powder of normal electrocorundum, and sintered corundum. A technology for the production of high-alumina mortars of three compositions has been developed for these materials. An experimental industrial batch of mortar composed of ShKN chamotte, polishing powder of normal electrocorundum, and DN2 clay has been manufactured and tested with a positive result. Production of the mortar has been introduced in the Belokamensk Refractory Plant.Translated from Ogneupory, No. 1, pp. 27 – 28, January, 1996. 相似文献
890.
S Gilfillan M Bachmann S Trembleau L Adorini U Kalinke R Zinkernagel C Benoist D Mathis 《Canadian Metallurgical Quarterly》1995,25(11):3115-3122
Mice with a null mutation in the terminal deoxynucleotidyl transferase (TdT) gene harbor immunoglobulin and T cell receptor repertoires essentially devoid of N-region diversity. Consequently, the CDR3 loops important for antigen recognition are shorter and considerably less diverse than those of wild-type controls. We find surprisingly normal immune responses in TdT0 mice, as regards both efficiency and specificity. This provokes a reconsideration of the assumption that N-region diversity is required for an effective T and B cell repertoire. 相似文献