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991.
This paper deals with feasibility studies for a solar-assisted heating system for the University of Miami's Aquatic Center using the simulation program TRNSYS. The Aquatic Center is composed of an outdoor olympic size swimming pool and locker room building. The solar heating is accomplished by employing hot water generated by heat exchange with the solar collector working fluid. Two thermal storage tanks are employed for the collector and domestic use. The performance of the system is analyzed from both thermodynamic and economic standpoints and general conclusions are reached. 相似文献
992.
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Language-level support for object persistence frees programmers from having to confront a broad class of database issues from within their applications. By virtue of its metaobject protocol, CLOS is a language whose semantics can be tailored by individual programmers. We used the metaobject protocol to extend CLOS with support for object persistence. Our goal was to obtain a version of CLOS with persistence to which we could easily port a commercial geometric CAD modeling system. We describe the design and implementation of our persistence extension and highlight the strengths and weaknesses exhibited by the CLOS metaobject protocol during our experiment. For many aspects of the implementation we found that the metaobject protocol was ideal. In other cases we had to choose among paying a large performance penalty, extending the protocol, and bypassing the protocol by modifying the language implementation directly. 相似文献
995.
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997.
高速连续数据记录系统中双页缓存的设计和实现 总被引:2,自引:0,他引:2
在高速连续数据记录系统中,存储设备需要速度匹配单元来实现高速连续数据记录,文章讨论了双页缓存在高速连续记录系统中的作用,并以实际开发的记录系统为例,详细介绍了双页缓存的设计和实现。 相似文献
998.
关于职业技术学院英语教学的思考 总被引:2,自引:0,他引:2
马巧茹 《陶瓷研究与职业教育》2003,1(3):13-14
为了适应新形势、新需求,根据职业技术教育的实践,探讨如何调动学生英语学习的积极性,激发学生的学习动力,以改变被动学习和由此而产生的逆反心态,使英语学习收到好的效果。 相似文献
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1000.
The current model for the tricarboxylic acid cycle in Dictyostelium discoideum is based on extensive experimental studies of enzyme kinetics in vitro and of metabolite fluxes measured in vivo. In the previous papers (Shiraishi, F., and Savageau, M. A. (1992) J. Biol. Chem. 267, 22912-22918; 22919-22925; 22926-22933; 22934-22943) of this series we have carried out extensive analyses of the current model within the framework of biochemical systems theory with a view toward understanding the behavior of the integrated system. The model was found to be ill determined with respect to at least three of its features. In this paper we propose a minimal modification in the model that is consistent with previous experimental data but also includes recycling of amino acids for protein synthesis, one of the neglected features identified as important in the previous analysis. We again perform an analysis within the framework of biochemical systems theory to determine the systemic consequences of this change. The results show that the robustness of the modified model, as determined by the parameter sensitivities, is improved by 2 orders of magnitude over that of the previous model. Analysis of the dynamics shows that the turnover times for the pools of alanine, glutamate, and aspartate are reduced by 2 orders of magnitude and made more physiologically realistic. The distribution of flux is no longer rigidly fixed, and problems previously centered on the metabolism of pyruvate have been partially alleviated. Continued discrepancies lead us to question the degree to which kinetic data obtained with purified enzymes in vitro faithfully reflect the kinetic behavior of the integrated enzyme system in vivo. We must continue to re-examine the manner in which the kinetics of reactions in vivo are represented and to reassess the physical conditions that prevail in vitro and in vivo. Results in this paper direct our attention toward specific aspects of the system where these efforts should be focused. Thus, a minimal modification of the previous model has led to several improvements that make it more representative of the tricarboxylic acid cycle in D. discoideum, and the analysis in this paper leads to further predictions for improving the model. 相似文献