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91.
92.
Li Yourong Jin Mingcong Tang Jingwen 《保鲜与加工》1993,(6):46-50
The concept of loss rate of available energy was introduced for evaluating heat exchanger performance. At the same time, the general expression of loss rate of available energy was obtained for heat exchangers of several typical. And NL criteria was recommended for evaluation of the loss rate of available energy of heat exchanger. Then. the influences of inlet temperatures ratio, heat capacity ratio of fluids, the number of heat transfer units and flow patterns of heat exchanger on ,VL criteria were also discussed. 相似文献
93.
Liu Yuwen Liang Xichang 《保鲜与加工》1993,(1):64-66
Based on the infroduction of the present process of quenched internal gear, a new technolgy of machining quenched internal gear-EDM generating technology is presented with its principle and machining processes. . 相似文献
94.
The mathematical relationship for assessing total energy consumption within a material life cycle is presented in this paper. According to the relationship,the procedure rationality of recycling waste may be assessed quantitatively. 相似文献
95.
This paper ainalyses the size effect of the fracture energy of concrete tested bythree point bending. It is shown that positive errors of test results of fracture energy increase,ornegative errors decrease with increasing of the specimen ize. The phenomenon is one of main causesresulting in the size effect of fracture energy. 相似文献
96.
In this paper the problem of energy consumption and environment in the birdhouse is introduced and the reconstructive measures aiming at energy savings are recommended. The measures include the limitation of temperature region, reconstruction of the building envelop and using the sunny board at the south side of the birdhouse roof. Finally, the energy efficiency of the reconstructive project is estimated. 相似文献
97.
BAI Xue lian 《保鲜与加工》2002,(8):77
It is proved that planting is effective to improve environment both indoor and outdoor resulted from the functions of plants to clean air and save energy. So the contradiction between saving energy and comfort,healthy demanded by people can be solved by planting. The planting have being emphasized and expanded during recent years,but in the planting plan,just the function of beautifying the environment is concerned and the function of ecological and saving energy are neglected. The analysis on the ooptimum system of planting is to make the planting system as an organic composition in the effectiveness structure and space layout of the city. Based on the study on equivalent relation of different effects on environment, the optimum system of planting structure will be determined in order to achieve the integrated effects of planting on environment. 相似文献
98.
Discussion about Saving Energy in Refrigeratory 总被引:1,自引:0,他引:1
Food refrigeration is regarded as a high energy consuming trade. Under the long period system of state operated enterprise,there are many phenomenons of ignoring energy management and wasting energy. Energy consuming is not very clear for production.Consuming in our country is far more than the international standard and there is a distance between the middle_westland and the eastland. As a enterprise that faces the international market,it is important for it to strength the management so that the cost can be reduced. Considering those phenomenons of ignoring energy management and wasting energy in refrigeratory at present, some measures such as improved the unreasonable operation process, strengthening the energy management and automation to realize automatizing operation are improved to reduce the cost for refrigeratory trades. 相似文献
99.
为降低建筑能耗影响因素间复杂相关性对模型性能的影响,建立了一种基于KPCA-WLSSVM的建筑能耗预测模型。利用核主元分析(KPCA)对输入变量进行数据压缩,消除变量之间的相关性,简化模型结构;进一步采用加权最小二乘支持向量机(WLSSVM)方法建立建筑能耗预测模型,同时结合一种新型混沌粒子群-模拟退火混合优化(CPSO-SA)算法对模型参数进行优化,以提高模型的预测性能及泛化能力。通过将KPCA-WLSSVM模型方法应用于某办公建筑能耗的预测中,并与WLSSVM、LSSVM及RBFNN模型相比,实验结果表明,KPCA-WLSSVM模型方法能有效提高建筑能耗预测精度。 相似文献
100.
Zhu Caichao Qin Datong Li Runfang Chen Zongyuan 《保鲜与加工》1997,(5):26-32
The epicyclic gear drive with internal tooth is analysed,a dynamic analysis model which is based on the compatibility conditions of deformation is set up.On the basis of this model,the analysis of dynamics and kinematics is made,and the influence of design parameters on dynamical characteristic is also studied. 相似文献