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81.
农电企业降损节能工作的探讨 总被引:1,自引:0,他引:1
阐述了农网降损节能的意义和技术上,管理上的有效措施,指出在线损管理中,只有将理论计算,准确统计,科学分析,营业管理和严打窃电等一系列办法有机地结合起来,才会有良好的效果。 相似文献
82.
V. N. Reva 《Journal of Mining Science》2002,38(1):31-34
Using the energy approach as the base, the criteria are developed for brittle rock failure in outcropping in the workings driven in the rock masses of different degree of disturbance. A method is presented for estimating the stability of workings under conditions of zonal disintegration. 相似文献
83.
冬冷夏热地区户式空调设计与节能分析 总被引:3,自引:0,他引:3
以一单元式住宅的风道式户式空调系统为例,探讨了冬冷夏热地区户式空调的新风量确定方法,分析了户式空调的负荷特性,节能设计及户式空调系统的设计负荷与设计风量。 相似文献
84.
C. Ranganathaiah 《应用聚合物科学杂志》2002,86(13):3336-3345
I measured positron lifetime in natural polymer–cotton fibers as a function of isochronal annealing temperature in the range 27–290°C. The variations in the positron results indicated structural changes occurring in the cotton fibers and determined the glass‐transition temperature as 80°C. Activation energies were measured separately for the crystalline and amorphous regions, indicating the versatility of the technique. These values were close to the O? H bond dissociation energy, suggesting O? H bond dissociation, the most probable process occurring under thermal treatment. As an extension of the positron results, the molecular weight of the cotton fibers was determined to be 1,200,000 based on free volume, which was within the range suggested for cotton. There seemed to be an indication that crosslinking changed the spiral structure of cotton fibers to the network type. However, this needs to be validated by other measurements. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 3336–3345, 2002 相似文献
85.
An open‐cycle ocean thermal energy conversion (OC‐OTEC) system is one of the energy conversion methods used to generate electricity from ocean thermal energy. For the OC‐OTEC system, steam evaporated from the surface seawater due to flash evaporation drives the turbine. At that time, dissolved gas such as air is introduced into the low‐pressure system (OC‐OTEC system) as the noncondensable gas, which degrades the performance of condensation heat transfer. In this paper, a small‐scale OC‐OTEC experimental unit experimentally investigates the effect of noncondensable gas on the heat transfer performance in a condenser. The experimental results are discussed in comparison with theoretical estimation by the Sparrow–in method. It is shown that the condensation is occupied by heat and mass transfer near a condensation surface and that the condensation efficiency is affected by exhaust quantity of noncondensable gas at a relatively high concentration ratio of condensable gas. © 2005 Wiley Periodicals, Inc. Electr Eng Jpn, 154(1): 29–35, 2006; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20179 相似文献
86.
介绍了太阳能热风发电的产生背景、技术原理和特点。太阳能热风发电能够实现由太阳能到空气动能,最终到电能的转变,具有环保无污染、运行维护简单、缓解常规能源消耗等特点。简要介绍世界上第1座试验性质的太阳能热风发电站。对太阳能热风发电技术相关研究历程从试验研究和理论研究2个方面做了综述,重点介绍了澳大利亚电站的建设进展及最新相关学术研究进展,包括过渡段理论及试验研究、系统数值模拟和太阳能热风发电技术在高山地区的应用等。介绍我国太阳能资源情况,指出我国太阳能资源丰富,适合建造大型太阳能热风发电站。 相似文献
87.
Damiana Chinese Antonella Meneghetti Gioacchino Nardin Patrizia Simeoni 《国际能源研究杂志》2007,31(9):829-848
A mixed integer linear programming model combined with a more traditional design by scenarios is proposed to optimize facilities size and operation mode of a municipal energy system involving significant civil centres and a hospital. Moving from the need of a new heat and power station for the local hospital due to the construction of new pavilions, the opportunity of involving other centres in the neighbourhood in a distributed cogeneration system is analysed, increasing system complexity step by step. Smaller cogeneration units tailored to hospital needs are rewarding ventures with relatively low risks but, in a country whose traditional power generation systems heavily rely on fossil fuels and where energy policy and market conditions can make it profitable to sell surplus power, district heating systems foster the installation of larger cogenerators and lead thereby to higher profits and to better performance as for primary energy savings and greenhouse gases emission reduction. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
88.
Energy minimization and design for testability 总被引:6,自引:0,他引:6
Srimat T. Chakradhar Vishwani D. Agrawal Michael L. Bushnell 《Journal of Electronic Testing》1994,5(1):57-66
The problem of fault detection in general combinational circuits is NP-complete. The only previous result on identifying easily testable circuits is due to Fujiwara who gave a polynomial time algorithm for detecting any single stuck fault inK-bounded circuits. Such circuits may only contain logic blocks with no more thanK input lines and the blocks are so connected that there is no reconvergent fanout among them. We introduce a new class of combinational circuits called the (k, K)-circuits and present a polynomial time algorithm to detect any single or multiple stuck fault in such circuits. We represent the circuit as an undirected graphG with a vertex for each gate and an edge between a pair of vertices whenever the corresponding gates have a connection. For a (k, K)-circuit,G is a subgraph of ak-tree, which, by definition, cannot have a clique of size greater thank+1. Basically, this is a restriction on gate interconnections rather than on the function of gates comprising the circuit. The (k, K)-circuits are a generalization of Fujiwara'sK-bounded circuits. Using the bidirectional neural network model of the circuit and the energy function minimization formulation of the fault detection problem, we present a test generation algorithm for single and multiple faults in (k, K)-circuits. This polynomial time aggorithm minimizes the energy function by recursively eliminating the variables. 相似文献
89.
多缝式烧嘴点火器具有燃烧效率高,火焰长度易调,炉膛温度分布合理等优点,经工业试验证明,该点火器能满足攀钢烧结点火工艺要求,并有明显节能效果。 相似文献
90.
The stored energy and the energy release during SPD(superplastic deformation)of a Zn-5Al alloy were studied.The alloy after rolling process gains more stored energy,and the as-rolled speciment can obtain maximum elongation and minimum flow stress without hot loding treatment before SPD.Experimental results show that stroed energy release process is along with SPD process and is also an impetus to SPD.The as -rolled Zn-5Al alloy has 48J/mol stored energy which was measured with DSC(differential scanning calorimeter)and conforms well to the calcuated value.The as-rolled Zn-5Al alloy after SPD with an elongation of 2500% releases 112J/mol stored energy,Analysis shows that the strain rate is in direct ratio to the rate of stred energy release. 相似文献