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971.
Yu. V. Sokolov 《Technical Physics Letters》2006,32(6):532-533
A carbon deposit formed during graphite spraying in an electric arc, as well as iron and chromium particles obtained by electrochemical deposition under certain conditions, possess fractal structures. Data on some physical properties, the size of fractal aggregates, and the fractal dimension D of carbon, iron, and chromium deposits are presented. Relations between the fractal dimensions and physical properties of deposits are considered. A possible mechanism of the fractal structure formation is discussed. 相似文献
972.
Hu P.J.-H. Tsang-Hsiang Cheng Chin-Ping Wei Chun-Hui Yu Chan A.L.F. Hue-Yu Wang 《IEEE transactions on systems, man, and cybernetics. Part A, Systems and humans : a publication of the IEEE Systems, Man, and Cybernetics Society》2007,37(4):481-492
Drug-related problems, particularly those that result from sub- or overtherapeutic doses of high-alert medications, have become a growing concern in clinical medicine. In this paper, we use a model-tree-based regression technique (namely, M5) and support vector machine (SVM) for regression to develop learning-based systems for predicting the adequacy of a vancomycin regimen. We empirically evaluate each system's accuracy in predicting patients' peak and trough concentrations in different clinical scenarios characterized by renal functions and regimen types. Our data consist of 1099 clinical cases that were collected from a major tertiary medical center in southern Taiwan. We also examine the use of bagging for enhancing the prediction power of the respective systems and include in our evaluation a salient one-compartment model for performance benchmark purposes. Overall, our evaluation results suggest that both M5 and SVM are significantly more accurate than the benchmark one-compartment model in predicting patients' peak and trough concentrations across all investigated clinical scenarios. M5 appears to benefit considerably from bagging, which has a positive but seemingly smaller effect on SVM. Taken together, our findings indicate supervised learning techniques that are capable of effectively supporting clinicians' use of vancomycin or similar high-alert drugs in their patient care and management. 相似文献
973.
974.
研究了实验室条件下1,3-溴氯丙烷的合成方法、工艺及合成操作要点。合成1,3-溴氯丙烷的最佳物料溴素、氯丙烯的配比为1.56:1,反应温度控制在20~25℃,收集沸点140-145℃的馏份即为成品。 相似文献
975.
穿着朴实,谈吐文雅,举止端庄,从他富有表情的脸上和那对炯炯有神的眼睛,折射出一个青年科技企业家特有的自信、干练、豁达与刚毅。他,就是上海上大玲珀化工科技有限公司的董事长朱勇强博士。在与他寒喧之际,记者感到朱博士是位思维敏捷、善于开拓、好学求进、富有创新精神和管理才能的既懂技术、又会经营的复合型人才。他谈吐中潜在的智慧、才干和创业的理念使记者佩服。 相似文献
976.
The main technical measures for increasing the nominal safety of the No. 5 unit of the Kursk nuclear power plant are presented:
optimization of the neutron-physical characteristics of the core, adoption of a comprehensive monitoring, control, and protection
system, switching to cluster-type control rods, adoption of a system for limiting radioactive emissions during anticipated
accidents with pipeline rupture outside the containment system.
__________
Translated from Atomnaya énergiya, Vol. 100, No. 4, pp. 320–327, April, 2006. 相似文献
977.
978.
Yu Lin Shiduan Cheng Wendong Wang Yuehui Jin 《Wireless Communications, IEEE Transactions on》2006,5(8):1971-1975
As a well-known multimedia stream transport protocol, TFRC provides smooth transfer rate under stable network conditions, and achieves good fairness to TCP. However, it is not flexible in heterogeneous mobile networks because the available bandwidth varies rapidly. This paper proposes a measurement based TFRC (MBTFRC) protocol, which uses passive bandwidth measurements at the receiver to improve the flexibility of TFRC. In addition, a window-based EWMA filter with two weights is used to achieve stability and fairness simultaneously. Simulation results verify the flexibility, stability and fairness of MBTFRC. 相似文献
979.
980.