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951.
加强企业能力建设向国际型工程公司模式发展 总被引:1,自引:0,他引:1
华北电力设计院工程有限公司在改制过程, 全面加强企业能力建设, 实现从“改革效益型”企业向“素质效益型”企业转变, 走国际型工程公司之路, 使企业竞争力不断提高。 相似文献
952.
953.
介绍了电力需求侧管理(PDSM)的基本概念和国外的实施情况,阐述了我国实施电力需求侧管理(PDSM)的紧迫性和可行性,分析了在我国实施电力需求侧管理(PDSM)的支持环境和技术支持措施,提出了有待进一步研究的问题。 相似文献
954.
DAIShaobin SONGMinghai HUANGJun 《武汉理工大学学报(材料科学英文版)》2005,20(2):109-110
The components of expansive soil were arwdyzed with EDAX, and it is shown that the main contents of expansive soil in the northern Hubei have some significant effects on engineering properties of expansive soil. Furthermore, the soil modified by lime has an obvious increase of Ca^2 and an improvement of connections between granules so as to reduce the expansibility and contractility of soil. And it also has a better effect on the modifted expansive soil than the one modified by pulverized fuel ash. 相似文献
955.
1Introduction Hyaluronan(HA)isakindofpolysaccharideofa highmoleculeweightcommonlyexistingintheextra cel lularmatrix(ECM)ofthevertebrate.Recentlymuchre searchhasbeendoneonapplyinghyaluronantothescaf foldintissueengineering[14].Preliminaryresultsofheat degradationhavebeenreportedforHA[5],howeverthe selectingofheatingtemperatureseemsabitrandom.In thisarticle,theauthorselectedtheheatingtemperature fromtheDTAcurve.Sincehyaluronaniscommonlyused underanimalheat(36.5℃40℃),thisstudydoesnot havec… 相似文献
956.
试验研究了捷达LPG/汽油两用燃料汽车的振动噪声特性。主要测量了发动机缸体和座椅的振动情况 ,对比分析了匀速和加速时燃用汽油和LPG的噪声特性。试验结果表明 :两用燃料汽车使用LPG时 ,发动机机体振动幅值比使用汽油时小 ;而加速过程中 ,在较低转速下使用汽油噪声较大 ,在较高转速下使用LPG噪声较大 相似文献
957.
A. G. Cherniavsky V. I. Gulyayev V. V. Gaidaichuk A. I. Fedoseev 《Canadian Metallurgical Quarterly》2005,18(3):139-145
This paper describes large space antenna projects based on application of a closed polygonal pantograph truss used for transforming, deploying, and prestressing the reflector structure. Their reflecting surfaces represent a flexible mesh fabric. Two means of maintaining the surface are discussed herein. The first technique is associated with employment of forces of the gravity field gradient. The second is based on the use of a flexible carcass prestressed by internal forces applied to the pantograph. Reflectors of the second kind have a rather complicated mechanical structure depending on the way of their attachment to a carrier. Provisions are made for supporting the reflector by an articulated arm linked with its central interface and through the use of tube beams, supporting the reflector periphery structures. During the design of the reflectors, special attention was paid to the problems of their structural simulations at the stages of their launching, deployment, and orbital motion. The deployable antennas considered can be enabling elements for many space missions ranging from communications to other satellite systems, including radar, remote sensing, interferometry, wireless power transmission, etc. They exhibit an enhanced stiffness of structure, required for the digit tele- and radio-communication and navigation, which makes it possible to diminish ray scattering, to raise the power of the accepted signals, and to prevent frequency losses. 相似文献
958.
Edgar M. Barriga Jae G. Jeong Makarand Hastak Matt Syal 《Canadian Metallurgical Quarterly》2005,21(2):91-98
A manufactured home is a factory-built house constructed in a controlled factory environment according to federal standards known as the Department of Housing and Urban Development (HUD) code. The manufactured home shares approximately 20% of the total housing units in the United States and plays an important role in providing affordable housing. However, in terms of material engineering, advanced techniques are scarcely used in the manufactured housing (MH) industry. The current material flow and control systems are characterized as independent demand systems that are based on the personal experience of the material managers. Although independent inventory control systems are widely used in many manufacturing industries, these systems lead to a large amount of inventory and have many drawbacks for the MH industry. On the other hand, dependent inventory systems can reduce unfavorable inventory levels using new techniques and present substantial benefits for the MH industry. This paper applies lean inventory control systems and supply chain management techniques to the current systems of the MH industry and proposes a new framework of material control systems as one of the system management tools. 相似文献
959.
介绍了空间网格结构分析设计软件的特点,阐述了其设计要点,提供了4个工程应用实例,可供工程设计参考。 相似文献
960.