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131.
通过对实际工况下LW-13/22型压缩机三级活塞的受力分析,建立了有限元分析模型,对整个载荷循环过程进行应力和变形分析,并由此得到了LW-13/22型压缩机三级活塞在实际工况时的应力分布特点及变形规律,求得了活塞最大应力位置和最大应力时的主轴转角。  相似文献   
132.
A new dynamical evolutionary algorithm (DEA) based on the theory of statistical mechanics is presented. This algorithm is very different from the traditional evolutionary algorithm and the two novel features are the unique of selecting strategy and the determination of individuals that are selected to crossover and mutate. We use DEA to solve a lot of global optimization problems that are nonlinear, multimodal and multidimensional and obtain satisfactory results. Foundation item: Supported by the National Natural Science Foundation of China (No. 60133010, NO. 60073043 and No. 700/1042) Biography: Zou Xiu-fen(1996-), female, Ph. D candidate, Associate professor, research direction: evolutionary computing, parallel computing.  相似文献   
133.
杜晓东 《甘肃科技》2003,19(8):60-61
探讨了点对点TCP/IP连接、动态IP地址的捕捉与发布,介绍了动态IP地址捕捉发布工具-DynamIP,分析了DynamIP的应用实例。  相似文献   
134.
A modified version of Young's experiment by Shahriar Afshar demonstrates that, prior to what appears to be a “which-way” measurement, an interference pattern exists. Afshar has claimed that this result constitutes a violation of the Principle of Complementarity. This paper discusses the implications of this experiment and considers how Cramer's Transactional Interpretation easily accommodates the result. It is also shown that the Afshar experiment is analogous in key respects to a spin one-half particle prepared as “spin up along x”, subjected to a nondestructive confirmation of that preparation, and post-selected in a specific state of spin along z. The terminology “which-way” or “which-slit” is critiqued; it is argued that this usage by both Afshar and his critics is misleading and has contributed to confusion surrounding the interpretation of the experiment. Nevertheless, it is concluded that Bohr would have had no more problem accounting for the Afshar result than he would in accounting for the aforementioned pre- and post-selection spin experiment, in which the particle's preparation state is confirmed by a nondestructive measurement prior to post-selection. In addition, some new inferences about the interpretation of delayed choice experiments are drawn from the analysis.  相似文献   
135.
对用熔体淬火再真空蒸发所制备的非晶态Te_(8l)Ge_(15)Sb_4薄膜的伏-安特性,直流电导率及玻璃转变温度等性能进行了研究。结果表明,这种材料具有较好的开关效应及较高的热稳定性,可用作开关器件等。  相似文献   
136.
本文利用样条能量配点法来分析高层框架结构。先将框架模拟成等效性质的正交异性连续体,然后选取样条函数与连续函数的乘积来构成该连续体位移函数,最后用能量配点法来求解。  相似文献   
137.
Summary Intraperitoneal injection of allogeneic liver cells from 43-day-old male fetuses into normal 60-day female goat fetuses resulted in persistent hemopoietic chimerism in surviving recipients without clinical evidence of graft-versus-host disease. Transplantation of normal fetal liver cells into preimmunocompetent goat fetuses affected with -D-mannosidosis may provide an alternative strategy for evaluating hemopoietic stem cell transplantation in the treatment of human lysosomal storage diseases.  相似文献   
138.
Summary A sensitive radioimmunoassay showed that circulating -interferon in the plasma of healthy individuals was low in children and reached the highest level in the young adult, then declined gradually with age. Circulating -interferon was 0.201±0.059 ng/ml in males (n=19) and 0.184±0.076 ng/ml in females (n=14) at ages 30–39 years old. It was noted that circulating -interferon was maintained up to a certain level even in elderly individuals.  相似文献   
139.
Summary A new potent antiauxin, -(5,7-dichloroindole-3-)isobutyric acid has been synthesized and shown to inhibit auxin-mediated elongation ofAvena coleoptiles and to stimulate root growth of rice seedlings. Its activity is stronger than -(p-chlorophenoxy)isobutyric acid and is comparable to that of 2,3,5-triiodobenzoic acid, which are typical antiauxins.  相似文献   
140.
切削刀具倒棱刃口挤压力的理论计算   总被引:1,自引:0,他引:1  
根据试验观察.揭出了刀具刃口带负倒棱时的切削模型。在此模型中,刀具刃口 存在一个“金属死区”。以新模型为基础.采用能量法,对高温、高应变率下刀具刃 口的挤压力进行了理论计算。所做工作的特点是:1)在材料变形分析中计入了挤压 层金属绕过刀具刃口时的过剩变形;2)进行有关材料变形与物理特性的计算时,考 虑了温度与应变率的影响。利用新研制的压电式切削测力仪进行验证试验,其结果表 明,理论计算值与实测数据较好一致。  相似文献   
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