电潜泵极限下泵深度的探讨

电动潜油泵是油田进入中后期开发阶段强有力的机械采油方法之一,在世界各主要产油国内均得到了较广泛的应用。本文从潜油多级离心泵泵轴的强度、刚度问题入手,应用纵横弯曲连续梁理论,探讨电潜泵的极限下泵深度。文末以国产200m~3/日电潜泵为例,说明了有关参数对泵轴的变形及强度影响的趋势,并对计算结果进行了分析讨论。     

KGT—3—WLT型微机励磁调节器

论述KGT-3-WLT型微机励磁调节器。它由单片微型计算机MCS-51构成,用以完成数字给定、数字触发和数字控制功能。介绍了该装置的原理、结构、功能和特性,并提供了详细的工业试验数据。     

An analytic approach to the height of binary search trees

By using analytic tools it is shown that the expected value of the heightH _n of binary search trees of sizen is asymptotically given by EH _n =c logn+ (log logn) and its variance by VH _n = ((log logn)²), wherec=4.31107 …. The same bounds have been obtained by Devroye and Reed [3] by completely different methods. Dedicated to Philippe Flajolet on the occasion of his 50th birthday This research was supported by the Austrian Science Foundation FWF, Grant P10187-MAT. Online publication September 22, 2000.     

适用于GIL-架空混合线路距离保护的整定方法

将GIL段串入架空线路后,线路阻抗特性会发生变化,对于阻抗参数敏感的距离保护,其保护范围会发生变化。为了使原有架空线路保护装置能够可靠保护混合线路,在理论分析的基础上,通过修改距离保护定值来维持保护装置保护范围,使得原架空线路保护装置在GIL-架空混合线路工况下仍然适用。计算方法在PSCAD仿真模型中得到了验证。     

Performance measurement of cross-culture supply chain partnership: a case study in the Chinese automotive industry

This study explores a performance measurement system for a dynamic supply chain partnership in a cross-cultural context. An initial framework is constructed by reviewing the existing literature, followed by an in-depth case study in the Chinese automotive industry, where the framework is refined to address the multi-cultural setting. A performance measurement, system which includes the relationship strategy and operational measurement criteria for a supply chain partnership, has been developed. The relationship strategy contains elements of strategy orientation, management style, interdependence, mutual organisational characteristics and common goals. The operational measurement criteria consist of commitment, trust, communication behaviour, information sharing, participation decision, quality, production performance, delivery, cost, supplier strength, attitude, compromise and loyalty. The last three operational measurement criteria are found to be particularly relevant to the cross-cultural feature. While existing studies tend to focus on either specific measures or individual organisations, this paper for the first time proposes a comprehensive framework to measure the performance of supply chain partnerships. The cross-cultural perspective provides a further unique view on how a performance measurement system can be responsive to the dynamics in practice.     

如何提高应用写作教学效果

进入21世纪以来,特别是随着素质教育的全面推进,写作教学更注重学生的心智培养及知识的内化过程,为此在教学实践中,力图一改传统的教学模式,尝试从激发学习兴趣、拓宽教学空间、运用“案例教学法”等几方面提高教学效果。     

Ergonomics--costs and benefits revisited

An earlier review reported a dozen cases where ergonomics applications had resulted in cost savings. A large number of publications which refer to the topics of the cost-effectiveness and cost-benefits of ergonomics can now be found. However, data showing the value of ergonomics applications remain scarce. Cost-benefit and cost-effectiveness studies are difficult to conduct for a number of reasons. While it is unlikely that the general case for the value of ergonomics can be proven, ergonomists must be in a position to discuss the potential costs and benefits of their work with clients. The Business case model is suggested as one way to structure an analysis of where a potential ergonomics application might reduce the risks to costs or the possibility of lost benefits.     

一种分析低压塑壳断路器分断过程的方法

提出一种分析低压塑壳断路器(MCCB)分断过程仿真的方法。该方法通过对ADAMS软件的二次开发,耦合电路、电磁场和机械运动方程,考虑电动斥力的作用,可分析各种因素对MCCB分断过程的影响。     

国外新一代塑壳断路器的现状和发展动向

介绍了近年来国外著名电气公司开发的新一代塑壳断路器(如双断点触头系统、电子脱扣器、可通信断路器、接地故障保护和剩余电流保护等)及其技术指标、产品结构特点和技术发展方向,对国外塑壳断路器的发展进行了全面的阐述。