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《电气》2011,(2):14-18
With the incessant development of power market reform,the existing cross-subsidy in electricity tariffs has become a critical problem in China’s power industry development.On the basis of the theories of cross-subsidy and electricity universal service,the authors take foreign countries’ experience as reference to design several solutions to cross-subsidies in electricity tariffs in different phases of China’s power industry development.Furthermore,the application and implementation of these solutions are analyzed in this paper.  相似文献   

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The author suggests that the confidence which many biologists have in problem-solving methods is unwarranted and that there are very important limitations in almost all current methods for solving biological problems. The standard problem solving approach that computer scientists use is outlined. An example of an error in an evolutionary tree problem-the case of the African Eve-is discussed  相似文献   

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无色透明材料形成的单层薄膜,其颜色由干涉色决定。以白光照射其表面,随薄膜厚度的增加,将出现一系列色彩,这是由薄膜干涉所致。我们可以根据薄膜颜色,估计薄膜厚度。显然,当厚度增大到后界面的影响可以忽略不计的程度(相当于只有一个界面的半无限大情形,本文简称“厚膜”),则“厚膜”颜色恢复为无色透明。半透明材料在基底上形成的薄膜系统,以白光照射所呈现的颜色,由于基底及吸收的影响,则不能简单地以薄膜干涉来分析。对于半透明薄膜系统,首先测量它的光强反射率谱和透射率谱,运用传递矩阵[1]方法计算出薄膜的介质光学常数,再以光学常数计算单层薄膜与“厚膜”的光强透射率谱与反射率谱及它们的色坐标。以菲涅耳公式计算出的反射率谱为半无限大介质反射率谱,这时的色坐标可视为“厚膜”的色坐标。  相似文献   

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A survey is provided of Japanese research on ceramic materials for substrates, microwave dielectric ceramics, piezoelectric ceramics, semiconducting ceramics, and superconducting ceramics. Novel processing technologies are described, covering the use of amorphous materials, superfine powders, lamination, multilayer thin films, porous ceramics, and superlattices  相似文献   

6.
Recent progress in inverse problems in electrocardiology   总被引:5,自引:0,他引:5  
The considerable progress achieved in the inverse problem of electrocardiography over the last decade has provided grounds for optimism about the possibility of approaching significant clinically relevant applications in the next decade. However, there are a number of basic questions that still remain. In addressing these questions, the authors feel it is important to seek solutions that emphasize physiological rather than mathematical significance. This approach leads to twin requirements for useful inverse solutions: accuracy, defined in a physiologically meaningful (and not just averaged and mathematical) sense, and reliability, not only to measurement noise but also to geometric modeling errors and other uncertainties that are inescapable in practical application. Studies using analytically tractable models may still be relevant, but it seems more important to find solutions to practical inverse problems, which will move the field toward wider acceptance and credibility  相似文献   

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我国阀控式铅蓄电池生产技术的进展   总被引:2,自引:0,他引:2  
本文为作者已发表的“国内阀控式铅蓄电池的生产技术经验”的续篇,主要叙述近四五年在这一方面的技术进展。  相似文献   

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龚源发  张晖文 《电力建设》2000,21(6):55-56,59
湖南省电力建设监理公司从1994年3月组建以来,在经营决策、规范管理、技术服务等方面都摸索出了一定的经验,创出了一批优秀成果.从1999年5月开始,按现代企业制度进行改组,2000年1月正式改组为湖南电力建设监理咨询有限责任公司,要求做到产权关系明晰、权责明确,政企分开、自主经营、机制健全、行为合理,管理科学、注重效率.  相似文献   

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提出了生产分时定向无功表和峰谷分时无功表的设想,以使现行的无功电能在与峰谷分时有功电能在相匹配,按峰、谷、平三个时段分别计算用户的功率因数数值,按三个时段分别计收功率因数调整电费,增加电网经济效益,改善电网电压质量。  相似文献   

10.
英国政府计划从2016年开始,所有新建住房都要达到碳零排放,并且制定了相关的标准。贝丁顿零能耗开发(Beddington zero energy development,简称BedZED)项目是一次有益的尝试,它是英国目前最大的低碳生态社区。社区坐落在伦敦的萨顿区,项目由英国政府开发商开发,包括可持续发展咨询公司、建筑师和工程师的设计团队联合设计了这个项目。  相似文献   

11.
Electroluminescence in insulating polymers in ac electric fields   总被引:1,自引:0,他引:1  
EL (electroluminescence) in several polymeric materials was investigated in the electric field range <90 kV/mm. We used polymeric films with semi-transparent gold electrodes: low density polyethylene, polypropylene, polytetrafluoroethylene and polyvinylchloride. The EL characteristics were very low EL inception fields (2 to 20 kV/mm) which strongly depend on the material and very low energy photon emission (mainly in the red region of 1.6 to 1.8 eV). These results reveal that EL emission occurs predominantly in the metal-polymer interface region rather than in the bulk of the polymer at the applied field. We present a model of EL emission in the metal-polymer interface region to explain our results qualitatively. In this model, the mechanism of EL emission is the radiative recombination of the electrons and holes trapped at the surface states of the polymer, which causes photon emission in the red region. The EL inception field and EL intensity depend on the density of the surface states of the polymers  相似文献   

12.
设计了一套基于超高频 (UHF)法的发电机定子局放检测系统 ,实验室研究结果表明该方法可检测到发电机定子各类局部放电 ,分析和比较了超高频信号在空气和金属导体中的传播规律。该系统与预先安装在某发电厂0 #机组上的方向传感器和中性点的电流传感器相结合 ,联合在线监测发电机的结果表明UHF法可准确检测到发电机中的局部放电信号 ,且信噪比极高  相似文献   

13.
赵学锋 《华中电力》2000,13(2):33-34
针对应用软件帮助文件存在的不足,设计中文帮助文件。介绍帮助文件基本概念和设计方法,可提高使用效率,有利于软件的推广 。  相似文献   

14.
分析了包头供电局对220 kV及以上变电站现行操作方式存在的问题,给出了变电站进行分组操作的方法,通过实例分析了进行分组操作的可行性及经济、社会效益.  相似文献   

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输电线路工程现已成为我国冻土工程的重要组成部分。通过分析发现,在世界各冻土大国输电线路的建设中,俄罗斯在多年冻土区输电线路建设历史最长,累积长度约接近10万公里,电压等级主要为220 kV和500 kV;在环境变化条件下,各国工程建设中均发现冻胀融沉、冻拔问题、不良冻土现象等冻融灾害对对塔基稳定性造成的严重影响;鉴于输电线路点线工程特性,可充分结合冻土发育规律、合理选线和设置杆塔,有效减少冻融灾害发生;桩基础是多年冻土区较为通用的塔基形式,冬季施工是重要的选择原则;热管等工程措施的采用是减少冻融灾害和维护塔基稳定性的有效途径。  相似文献   

17.
A paper describing advances in electronic PD site location devices through a system comprised of an added purpose-built analog-to-digital converter, which has been added to a previously developed, PC-based, digital PD detector  相似文献   

18.
微晶玻璃具有电阻率高、介电特性好、硬度高、机械强度大以及铁电性等特点,因而在电子元件中得到了广泛的应用。综述了近几年来电子元器件用微晶玻璃的研究进展。  相似文献   

19.
信息化工程参与传统产业企业升级改造,能够产生多大的发展空间?随着我国加入世界贸易组织,中国企业已经在本土和世界范围内直接参与了市场竞争。建设信息化工程,改变传统管理模式,提升核心竞争力,与全球经济一体化同步发展,是传统产业迈向现代化的重要途径。冰山集团大连三洋压缩机有限公司成功地应用了企业资源计划系统,在较短时间里,把企业的综合竞争能力提高到一个新的水平。在近期召开的现场示范及鉴定会上,本刊记者特地采访了大连冰山集团三洋压缩机公司总经理赵之海先生,以下即是这次采访的情况。  相似文献   

20.
Presents a study of streamer propagation in transformer oil, with point-plane and semi-uniform geometry. The latter is made of parallel plane electrodes, with a thin triggering point of calibrated size. By reducing the length of the point, it is possible to move progressively from a point-plane geometry to a quasi uniform geometry. The propagation of streamers is impeded by the presence of a metallic plane behind the triggering point, that reduces the field on propagating streamers. The effect varies widely according to the streamer type considered. The propagation of negative and fast positive streamers is nearly quenched, whereas slower filamentary positive streamers (usually responsible for breakdown in oil) are less affected. This shows that many results obtained in point-plane geometry can not be simply extrapolated to the more realistic case of uniform field  相似文献   

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