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61.
The authors conduct the experimental study and optimal computing for the condenser of automobile air conditioner. The especially the properties of heat transfer and flow at the side of air when using shutter fin. The authors the influence of several combinations of fin's geometry parameter to heat transfer and flow resistance. The maximal heat transfer is used as a criterion relation to select the fin's geometry parameters in the same facing air area of condenser. Furthermore, a program is designed to conduct optimal computing, and the computing results are basically consistent with experimental results. It shows that the optimal method is reasonable and the results can be applied to engineering practice. 相似文献
62.
63.
《保鲜与加工》1997,(6):58-62
In this paper,in terms of the measured data(including the deflection and slope at the ground surface of the pile,the maximum bending moment and its position),the biparameter method is used to analyze the pile-soil parameters.Two examples show that the method in present paper is reasonable and reliable,and it provides the reference value for the engineering design. 相似文献
64.
Liu Mingyu 《保鲜与加工》1997,(3):26-31
Through the analysis in this paper,the optimum relation of the discharging current peak interval t m ,the discharging loop equivalent inductance L and equivalent resistance R is obtained.This paper analyze the original discharging loop equivalent inductance L ,which provides an effective method for adjustment and selection of inductance L to realize the optimization energy saving design of the welding machine. 相似文献
65.
Liu Chongde Wang Xiaoming Gu Lan 《保鲜与加工》1992,(6):10-17
A optimal design with whole structure parameters and its program are carried out. A reasonable model is established. Using the method a optimal design with whole structure parameters by original parameters of American P&H2300xp excavator was calculated. The size,carried out by the method,approximates to the size of P&H2300xp excavator very well. 相似文献
66.
Huang Zongming 《保鲜与加工》1996,(3):42-48
Parameters dominating elasto- plastic earthquake response of SDOF systems,relation between ground motion amplitude and elasto- plastic response of SDOF systems are presented in this paper. 相似文献
67.
In system controlled,Sampling these parameters and with parameters for controller in time, it is an object to adaptive control. The article presents a scheme that the structure parameters on it's model and model parameters is robust identified by on line, while to optimal of algorithm on adaptive control is fulfilled. In control scheme, method of intelligent identifying to the structure parameters(levels of model) and algorithm of robust pole placement are introduced also It is advancer for already mentioned scheme. Whole scheme presents new model on adaptive control. 相似文献
68.
Development Management (DM) in decision phase, Project Management on behalf of the owner (OPM) in implementation phase and Facility Management (FM) in operation phase are three isolated management tools during traditional life cycle management of construction project. As a result, a lot of potential disadvantages are aroused. In recent years, many research organizations try to reform the traditional method using different integration means. This paper tries to explore into integration of DM, OPM and FM to overcome the malpractice of traditional life cycle management of construction project. The research focuses on three aspects: 1.putting forward the concept of Life Cycle Integrated Management (LCIM), based on management integration theory; 2. Raising a new idea to owner's (operator's) management organization design, which emphasizes on the balance of life cycle objectives; 3. Analyzing an information module, level and method of system integration of Life Cycle Integrated Management Information System. 相似文献
69.
70.
由于对边坡强度参数统计特性考虑不全面,使得边坡可靠性指标计算值偏小,对应的失效概率偏大,常常超过10%,设计中难以采纳,造成地基可靠度规范的制定和执行进展缓慢。以某高速公路全风化花岗岩土质高边坡为工程背景,在分析土质参数统计特性的基础上,采用极限平衡理论和蒙特卡罗模拟法,系统地分析了土质强度参数的均值不定性、变异性、相关性、区间特性和空间变化性等对边坡稳定可靠性的影响。结果表明:土性参数的各种统计特性对边坡稳定可靠性均具有不同程度的影响。可靠性指标计算值随抽样距离的减小而增加,随c或φ均值的增大而增加,随c和φ的变异系数的增大而减小,随c和φ相关系数绝对值的增大而增加,考虑区间性后可靠性指标计算值也明显变大。即变异性对边坡稳定不利,而相关性、区间性和空间变化性对边坡稳定有利。因此,准确而全面地考虑土质参数的统计特性,尤其是在参数变异性和相关性的基础上加以考虑土性参数空间变化性和区间性会更加符合工程实际,且计算结果趋于安全,有利于地基可靠度规范的推广运用和边坡工程的安全评价。 相似文献