变压器中低压后备保护与出线保护整定配合的研究

介绍了镇江电网变压器的中、低压侧后备保护的一般配置,阐述了变压器的中压侧或低压侧后备保护与出线有时不能相互逐级配合的情况,以及这种情况造成的危害。提出了解决这种上下级保护不能相互逐级配合的两种处理方法,并通过运行实践证明该方法是行之有效的。     

我国第一套国产化可控串补装置的阻抗控制

文章介绍了我国自行研制的第一套可控串补（TCSC）工程——甘肃220kV碧口——成县（简称碧成）线可控串补工程中可控串补系统的阻抗控制。系统试验证明：220kV碧成线可控串补系统能够平滑快速的进行阻抗调节，调节误差较小．响应速度满足工程要求。220kV碧成线可控串补系统控制器的设计已达到世界先进水平。     

封接工艺对玻璃与可伐合金结合性能的影响

采用正交试验方法研究了封接工艺对玻璃与可伐合金结合性能的影响。利用电子万能实验机和金相法分别测试了封接件的剪切强度和显微组织。结果表明：在封接工艺过程中，封接气氛(N2流量)是最主要的影响因素。封接温度次之，封接时间的影响最小。     

基于UC3638的PWM双极性电流控制器在TEC温控中的应用

阐述了基于UC3638的PWM双极性电流控制器构成的半导体热电致冷器（TEC）温控系统。对UC3638增强型PWM电机控制IC的特点进行了介绍。给出了由UC3638构成的TEC双极性电流驱动器的设计方法。给出的温控实验结果证明了基于UC3638的控制器是可行的。     

Application of Fuzzy-PID Control System in Full-Mechanized Coal Face

The control system, which includes structure, the composition of software and hardware, the form of PID control system and its systematic closed-loop, was used in No.4236 full-mechanized coal face of Xinlongzhuang mine.The typical fuzzy PID control system structure was investigated, and a simplified fuzzy PID control system was taken the place of the complex three-dimension fuzzy controller. Based on the parameter relation between fuzzy controller and normal PID controller, a common method of parameter adjustment of PID controller was summed up and the computer simulation was realized. This system can overcome the problems of large delay, nonlinear, poor running environment and great load change in the full-mechanized coal face. The simulating investigation indicates that the designing method of fuzzy controller is simple and feasible.     

Translation Surfaces with Zero Mean Curvature in （2+p）-Dimensional Pseudo-Euclidean Space E22+p or Ep2+p

Let Ep^2＋p（resp.E2^2＋p） be a （2＋p）-dimensional pseudo-Euclidean space with the index p （resp.2）. The maximal spacelike or minimal timelike translation surfaces M^2 in Ep^2＋p or E2^2＋p are considered and a complete classification is given.     

Heat regulating strategy in numerical control end milling for hard metal machining

The trend in die/mold manufacturing at present is towards the hard machining at high speed to replace the electron discharge machining. Failure forms of the A1TiN-coated micro-grain carbide endmill when used for the machining of/IS SKD61 (HRC 53), a widely used material in die/mold manufacturing, are investigated. The endmill shows a characteristic that tool life decreases greatly due to the chipping when overload occurs or the rapid increase of wear when over-heat accumulation in cutting edges. As a consequence of the investigation, a strategy to regulate heat generation in the end milling process is proposed. This is accomplished by controlling the cutting arc length, i.e. the length of each flute engaging workpiece in a cutting cycle. Case studies on the slot end milling and comer rounding are conducted. The results show that the proposed strategy suggests the optimal tool path as well as the optimal pitch between successive tool paths under the cutting time criterion.     

Water target based cross-calibration of CBERS-02 CCD camera with MODIS data

The CBERS-02, the second satellite of China Brazil Earth Resources Satellite series, was launched on Oct. 21, 2002. Onboard the satellite, there are three major sensors, a CCD camera, a wide field imager and an infrared multispectral scanner (http://www. cresda.com). The purpose of this paper is to calibrate the CCD camera with a methodol- ogy of cross-calibration. The spatial resolution of the multispectal bands of CCD camera is 19.5 m, the swath is about 115 km. It is capable of side…     

三维并行工程组织模块化产品开发

本文介绍了三维并行工程的概念与涵义，提出运用三维并行工程组织模块化产品开发的新方法，分为模块化设计、模块化制造、模块化定制与使用等。通过三维并行工程方法管理产品开发可以协调模块化设计、制造与使用之间的冲突。模块化策略部署矩阵、模块团队与交叉功能团队是实施模块化产品开发的有效方法。     

钛及钛合金仿生表面改性研究进展

钛及钛合金具有较好的生物相容性及优良的机械性能，在临床上得到了越来越广泛的应用。表面生物活性化能够进一步改善其表面性能，提高表面生物活性。本文对钛及其合金的仿生表面改性进行了综述，具体介绍了化学法、促形核剂法、自组装单分子法的活化机理，并对仿生表面改性的发展方向进行了探讨。