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211.
The implement of enterprise knowledge management gives rise to extensive research on its measurement. Based on the existing measurement theories and evaluation index systems of enterprise knowledge management during the past three years in China, this paper analyzes the problems in measuring target and designing the evaluation index system in the existing research findings, and explains detailedly why measurement target of enterprise knowledge management should be "level evaluation" instead of "performance evaluation", and definitely points out the meanings of enterprise knowledge management level and significance of its evaluation. This paper also indicates that the design of the evaluation index system should be complete, reasonable, proper and operable. 相似文献
212.
In this paper, in allusion to the three kinds of serious overvaluation (the budgetary estimate of project construction exceeds the rough estimate, the budget exceeds the budgetary estimate and the final accounts exceed the budget) causing uncontrollable project investment often appeared in domestic project construction,the main causes for that are analyzed. That is, the frequent project change and the malpractice of the cost managing system. In this paper, according to some real projects,the kinds and causes of project change are clarified and the malpractice of the cost managing system is analyzed. The effective approaches of reducing the project change, especially the united surveying and improving the cost managing system in order to make the effective control of the project investment are realized. 相似文献
213.
When analysing the performance of casting powders in a specific casting machine, the thickness of liquid slag is a very important parameter. If the liquid slag thickness is not kept above a certain minimum value during the continuous casting operation,the surface and internal quality of the cast products will be jeopardised because lubrication between the strand and the mould is impaired . It is necessary, therefore , to choose the appropriate type of mould powder .In the industrial experiments, it is very difficult and expensive to study this sensitivity by introducing controlled variation in one parameter while keeping all the other constant. Numerical and computer simulation methods are used in the study .They can predict the liquid slag thickness developed above the liquid steel and distribution of the temperature. The sensitivity of the liquid slag thickness to variations can be determined in the material properties of the mould powders. 相似文献
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215.
Peng Xiaodong Qian Hancheng Zhang Xiaomei 《保鲜与加工》1992,(5):77-82
The spraying codeposition process is used to produce metal matrix paniculate composites, whose technical procedure and main processing parameters are analyzed. The microstructure of the composites is examined and the properties are tested. The solidification characteristics in the spraying deposition and solidification process are discussed. The results indicate that several problems involved in conventional methods can be overcome with this technique to preduce metal matrix paniculate composites. The reinforce particles are dispersed in the matrix homogeneously without solidification segregation. Compared with the matrix alloy,the composite proves to be harder and has excellent wear resistance. 相似文献
216.
鸡新城疫油佐剂灭活疫苗的研究 总被引:3,自引:2,他引:3
采用ND Lasota株为种毒,福尔马林为灭活剂,7号白油为佐剂,吐温80、司本80为乳化剂,硫柳汞为防腐剂,高压匀浆泵为乳化工具,研制出ND油佐剂灭活疫苗。其剂型为双相型(W/O/W),呈稀薄乳状液,粒度为1um左右,粘度≤1s,通针性好。4 ̄8℃有效保存期1年。效力≥70PD50,最早产生免疫时间为12天(100%保护),生产中常用免疫剂量为2月龄内每只0.5ml,2月龄以上每只1.0ml皮下 相似文献
217.
ZHENG Zhao-xiang XIONG Yi-jie LIU Qian-ling QianXi County Water Conservancy Bureau QianXi China 《华北农学报》2006,(Z3)
建国以来,黔西县小水电建设在省、地主管部门的关心支持和当地党委、政府的正确领导下,经过多年努力取得了一定成绩。但近年来由于种种原因,小水电建设未能继续向前发展,致使全县水能开发利用率极为低下。当前,农村小水电正面临着前所未有的大好发展机遇,分析全县农村小水电建设管理工作中存在的问题及其原因,研究相应的对策,对农村小水电的发展具有重要意义。 相似文献
218.
以樊口泵站的工程实际为背景,运用CFD数值模拟技术和方法,以肘型进水流道,屈膝式出水流道及40CJ-95型轴流泵为具体对象,对泵装置整体进行全面系统的研究.在额定转速下,改变叶片安装角,分别模拟各种不同叶片安装角下的工况,预测水泵性能,并和实际特性曲线进行比较;分别改变转速和叶片安装角,针对模拟结果分析预测装置性能,与模型试验值进行对比.结果表明:用基于有限体积法的双方程紊流模型对泵装置整体进行数值仿真研究,是可行、有效的;并且通过与已有实验成果比较,得出模拟计算结果与试验值吻合较好,表明计算结果可信. 相似文献
219.
220.