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101.
海河二道闸和防潮闸优化调度研究 总被引:1,自引:0,他引:1
汛期为腾空海河河道并保证二道闸下咸水不致上溯,二道闸闸下水位应控制在1.0m左右。利用一维非恒定流模型对海河自西河闸至入海口河段进行数值模拟,研究了西河闸分流量为80、100、120m3/s3种情况下,海河防潮闸和二道闸优化调度结果。 相似文献
102.
在喷灌工程规划设计过程中,正确地选用规划设计方案,实际是一个综合分析决策的过程。主要应考虑的因素中,有些可定量,有些则是无法定量的。如何对非定量因素作定量分析,进而对整个喷灌规划设计方案作出评价决策,层次分析法是解决这类问题简洁、有效、实用的方法。 相似文献
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104.
Wang Dongyun 《保鲜与加工》1988,(1)
On the basis of outlining our present situation of city water supply and itsgeological map compilation,this paper suggests a new principle which should befollowed in the compiling work of city water supply hydrogeological maps and themain contents of compilation and the ways of expression as one of the map com-piliing plans to be discussed in this field. 相似文献
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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
108.
It is important for enterprises' inventory management to find out the optimal production cycle and the length of shortage time,so that the total cost of inventory system can be reduced and the service level can be raised.Based on the classical EPQ model,this paper develops an EPQ model for deterioration items with different lost sale factor relative to the inventory level during shortage period.The existence of unique optimal solution is discussed by mathematic analysis and a numeric example.The sensitivity analysis shows that the parameter of losing sale has different impact on the costs of inventory system.The factors must be considered for the production inventory system to make management decision. 相似文献
109.
Voltage fluctuation and flicker is one of the main causation that imperils reliability of power supply. Steelmaking EAF with large load of distribution network produces large impact and interference on the public electric network in operation. So it is very important to control reactive power for voltage fluctuation and flicker mitigation. STATCOM possessing high response speed is an effective measure to mitigate voltage fluctuation and flicker of distribution network. Here, comparing to static var compensation, many advantages of STATCOM are analyzed. Operation principles COM mitigating voltage fluctuation and flicker, general control strategies and control method are introduced cussed. The researching pivot and trend in the future are also discussed. of STAT- and discussed. The researching pivot and trend in the future are also discussed. 相似文献
110.