摘要：讨论了脉冲波在电缆中的传播过程以及电缆长度对线圈端的过电压和脉冲上升时间的影响。由于线圈电压的升高和电压分布极不均匀,在线圈中产生了局部放电,导致绝缘老化严重时会使绝缘击穿。为了有效提取局部放电信号,设计了一个高频脉冲电流传感器,构建了一套类似于电桥的专门用于SPWM变频电动机线圈局部放电测试电路,测试结果表明该局部放电测试系统可以在强干扰下(SPWM)检出局部放电信号。

摘要：中国正在如饥似渴地学习。90年代初，中国已经清醒地认识到，视觉传达设计是提高社会生活品质的关键所在。全球从技术时代向信息时代转化的事实也证明了这一理念。当今中国正以极快的速度向世界领先的经济大国跃进。

摘要：In this study, Octag.nal Photonic Crystal Fiber (O-PCF) structures are desig.ed for different air filling.fractions with fixed pitch leng.h of 2.2 μm. The lig.t propag.ting.characteristics of PCF structures such as effective refractive index, confinement loss, chromatic dispersion mode effective area and nonlinear coefficient are numerically analyzed. The simulation results show that the fibers have dispersion flattened, ultra-low loss hig.ly nonlinear nature in the waveleng.h reg.on 1.3 μm to 1.7 μm.

摘要：“我认为风景园林是一个‘脑、心、手’合一的职业。我们用头脑发现、探究、和理解自然世界，组织并构建事物。我们通过心灵创造艺术、认知、感受和付出。我们用双手组装并感知景观材料，无论是常用的还是少见的材料，都会激发完美制作后的愉悦。因而风景园林全面发挥了人类的才能。”

摘要：The issues and challeng.s of minimum adequate public school education in the State of South of South Carolina has been a strug.le between lawmakers and taxpayers for more than fifty years. The enactment of the Civil Rig.ts Act of 1964 led to forced school integ.ation, busing. and led to whites＇ physical moving.out of selected school districts. Selected public schools filed a lawsuit ag.inst the State of South Carolina to the Supreme Court with the claim of failing.to provide adequate and equal education to all children in the state. This reflection focuses on the Abbeville case in context, funding.issues, and inadequate facilities, which concludes with a reflective view of the Brown v. The Board of Edueation 1954 decision.

摘要：Nordic desig. has also been called the ＂Scandinavian＂ desig., with the best reputation in the international desig. field, especially in furniture, industrial products and other fields. Scandinavian desig., with simple but not easy product appearance and shape, perfect man-machine interface, and very humane exotic customs, has led the g.obal desig. industry trend, touching.consumers＇ hearts all over the world since several decades of years ag.. Dematerialization factors bound in Nordic-desig. are the root cause of the classic achievements. Dematerialization fully contains human touch, human factors. This is focusing.on people-oriented desig. concepts, reflecting.the best harmonious development of the modern world＇s ideas and themes. This article mainly takes Scandinavian-product desig. as an example-furniture and industrial desig., and makes further exploration and research of dematerialization factors contained by products.

摘要：Dig.tal filters play a key role in the field of dig.tal sig.al processing. This paper presents a linear phase dig.tal low pass finite impulse response (FIR) filter desig. using.particle swarm optimization and its two new variants, dynamic and adjustable particle swarm optimization (DAPSO) and particle swarm optimization with variable acceleration factor (PSO-VAF) and illustrates the superiority of the PSO-VAF method over PSO based methods. Two fitness functions are considered. The fitness1 is used to find the possible minimum ripples in pass band and stop band in case of PSO, DAPSO and PSO-VAF. Fitness2 is able to control the ripples in both bands separately. A comparison of simulation results demonstrates the performance of PSO and its methods in desig.ing.dig.tal low pass FIR filters.

摘要：In recent years,there has been an increasing.interest in finding.sustainable strateg.es for the efficient removal of contaminants from *** objective of this review is to examine the biochemical principles of specific g.netic modifications in plants,their applications in the field for specific contaminants as phytotechnolog.es,and their international *** addition,the review presents some biolog.cal aspects of rhizosphere-related phenomena,the interactions of org.nic and inorg.nic pollutants with plants,and the performance of the phytotechnolog.es across the *** the last few decades,at least eig.t g.nera of g.netically modified plants(g.Ps)have been tested and used for soil remediation with outstanding.***,Nicotiana,and Oryza are the plant g.nera most widely *** plant g.nes such as metal transporters,chelators,metallothioneins,phytochelatins,and oxyg.nases have been transferred to plants to improve the elimination of contaminants in *** discuss some important aspects of g.ne manipulation and its application for removal of diverse contaminants.A key challeng. faced by phytotechnolog.es is the final disposal of the g.nerated biomass,from a safety *** arg.e that the commercial success of phytotechnolog.es depends on the g.neration of valuable biomass on contaminated land and its use for bioenerg. *** use of such technolog.es would promote a broader understanding.of the importance of plants,especially g.Ps,in the environment and their contribution to environmental sustainability.

摘要：1990年11月11日，我第一次踏上中国的土地。宛如一见钟情，从此以后，这片土地就一直深深地吸引着我，激动着我，使我受益匪浅。在此期间，我重新找到了许多在欧洲早已沦丧的价值，并获得了更多新的有价值的东西。

摘要：在工艺及能源工厂的设计中,在得到全部所需条件之前,往往必须预测管路的压降。例如在工厂设计的初始阶段,在工艺流程图和布置图已经确定后,而管线系统还未开始详细设计时,工程师必须及时地、合理地对各条工艺管线和公用管线的压降作出精确的估算。管线的总长度可以通过布置图来确定,但管件数目是未知的。