链

The article presents the developing condition of PWM and SVPWM first.Then the theory of SVPWM is discussed in detail.The SVPWM is based on the thought of magnetic chain tracking.It makes the ideal magnetic chain circle of three-phased sysmmetry electric motor supplied by three-phased sysmmetry sine wave voltage for basis,uses the practical magnetic chain vector formed by the different switch modes of three-phased inverter to track the basic magnetic chain circle.During the course of tracking,the inverter changes the switch modes properly to form the PWM waves.Then the modulation wave of SVPWM is analyzed in detail.The modulation wave of SVPWM is implicit,but the analogous modulation wave in A-B-C axis needs to be calculated in order to expose the internal relation of SVPWM and SPWM.That is to show the implicit modulation wave of SVPWM. SVPWM actually is a transformed SPWM ruly sampled by the modulation wave which is injected by the zero prefaces based on space vectors.

本文首先对脉宽调制技术的发展现状进行了综述，在此基础上分析了电压空间矢量脉宽调制技术的发展现状；接着对空间电压矢量脉宽调制技术的基本原理进行了详细的分析和推导，SVPWM是基于磁链追踪的思想，它以三相对称正弦波电压供电下三相对称电动机定子理想磁链圆为基准，由三相逆变器不同开关模式下所形成的实际磁链矢量来追踪基准磁链圆的，在追踪的过程中，逆变器的开关模式作适当的切换，从而形成PWM波；然后详细分析了电压空间矢量脉宽调制技术的调制波，虽然SVPWM法的调制波是隐含的，但是为了揭示SVPWM法与SPWM法的内在联系，需要求出SVPWM在A-B-C坐标系上的等效调制波，也就是将SVPWM的隐含调制波显化；SVPWM实质是一种基于空间矢量在三相正弦波中注入了零序分量的调制波进行规则采样的一种变形SPWM。

The website that lacks a link is not a good website, link respect can link website of authority of cause of person of the same trade appropriately, for instance news website, linking sina, Sohu is should, the first let sight-seer feel him website is authoritative, engine of the 2nd all alone letting search knows you also make news.

缺少链接的网站不是一个好网站，链接方面可以适当地链接到同行业权威网站，比如新闻网站，链接到新浪、搜狐是应该的，第一让游览者觉得自己网站权威，第二让搜索引擎知道你也是做新闻的。

At the same time can participate in the exhibition show the product and conveyor belt: rubber, flame retardant, metal, polyester, nylon conveyor belt, conveyor belt, chain, belt protection devices; ribbon, steel mesh, Teflon net, fiberglass net transport technology and equipment related products, as well as belts, hanging, sheet metal chain, differential chain, roller, telescopic type, sorting, electric rail car, rail, pipeline and other transportation lines, speed chain , plug-in, packing, shock absorber production line; hand push-type, sheet-style assembly line, electrical test line, pushing the ring line, coating line, automatic guided vehicles transport systems, pipeline systems, pipeline technology and equipment related products.

此次展览会是在青岛国际会展中心由中国机械工程学会物流工程分会与中国机械工程学会机械传动分会共同主办，同时由青岛海瀚会展有限公司承办的。同时在展会中可以参加展会的产品有输送带和网带：橡胶、阻燃、金属、聚脂、尼龙输送带，输送网带，输送链，皮带保护装置；织带，钢板网，铁氟龙网，玻纤网等输送技术与装备方面的相关产品，还有皮带、悬挂、钣链、差速链、辊道、伸缩型、分拣、电轨小车、轨道、管道等输送线，倍速链、插件、包装、减震器等生产线；手推式、钣式装配线，电器检测线，手推环形线，涂装流水线，自动导向车输送系统，输气管系统等流水线技术与装备的相关产品。

Our results show that the duality of self-dual tetrahedral link is "trivial", and the duality of hexahedral and octahedral link as well as dodecahedral and icosahedral link are "nontrivial".

从构型角度考虑，四面体链环的自对偶是&平凡&的，六面体链环和八面体链环，十二面体和二十面体链环的对偶是&非平凡&的。

This research is taking sea perch as the material, and cloning the Syntaxin 1B gene. After extracting RNA from sea perch tissue, we gained the first chain of cDNA by RT-PCR. Then designing a pair of primers according to the sequence of Syntaxin 1B from other organism. Based on the first chain of cDNA cloned from sea perch, the partial sequence of Syntaxin 1B gene is been cloned by using TD-PCR and we received the 751bp fragment at last.

本实验从鲈鱼脑组织中提取总RNA，通过反转录得到cDNA第一条链，根据已克隆出的其它生物的Syntaxin 1B基因序列，设计并合成引物，在妒鱼syntaxin1B基因部分序列克隆与分析 cDNA第一条链的基础上使用降落PCR，进行体外扩增妒鱼 Syntaxin IB基因的部分序列，得到长度为75 lbP的片断，在胶中洗脱下该片段，与pMD 18一T载体链接，转化入感受态细胞，挑取阳性克隆扩大培养，提取质粒，经HindIH和x一gaH两内切酶消化得到75 1 bp的片断，证明链接成功。

It was pointed that encoding is important to DNA computing, in the implement of the DNA algorithm, the technique was used which is to safeguard 3＇ margin or 5＇ margin of DNA sequence corresponding the two points in order to find out all chains, and electrophoresis could be applied to arrange all chains and to throw off all the chains whose length exceed summation of weigh in graph, The probe with biotin to observe and register intensity of bright point to filter all paths; finally the orders of all paths can be obtained to analyze the recordation of experimentation.

得到路序。指出编码问题在DNA计算中的重要性。在算法实现过程中，用保护两端点对应的DNA片段3'端或5'端的办法得到所有的链，并用电泳的方法对链进行排序以及去掉链长大于图权值总和的链；对探针进行生物素标记并且采用观察、记录亮点强度的办法筛选出所有的路；分析实验记录得到路序。

Based on aforementioned findings, the author disclosed China have gone through three wave of marketing since the open policy reform in the end of seventies in the last century: the first wave taken place from the end of seventies to the end of eighties of last century, during this period of time, enterprises commonly took a marketing tactics mix of unitary product, high gross-profit pricing, wholesale and information notification; the second wave happened from the end of eighties to the end of nineties in the last century, during the second wave, enterprises often took a marketing tactics mix of serialized products, medium gross profit pricing, regional distribution and advertisement on mass media; the third wave occurred from the end of nineties of last century to now, during the third wave, enterprises usually adopted a marketing tactics mix of segmented products, low gross profit pricing, outlet interception and tangible benefits promotion.

基于上述认识，本书进而揭示出，中国市场自上个世纪70年代末改革开放以来，已经经历了三次营销浪潮：第一次营销浪潮发生在20世纪70年代末至80年代末，期间，企业界普遍采取的是&单一化产品+高毛利政策+批发销售+信息告知&的链接标记营销策略组合。第二次营销浪潮发生在20世纪80年代末至90年代末，期间，企业界普遍采取的是&系列化产品+中毛利政策+区域链接标记分销+大众链接标记广告&的营销策略组合。第三次营销浪潮发生在20世纪90年代末至今，期间，企业界普遍采取的是&细分化产品+低毛利政策+链接标记终端拦截+实惠促销&的营销策略组合。

The chain conveyor uses models the steel link joint or the stainless steel link joint connection manufactures, thus may achieve certain lengths according to the request the transportation, in the rack installs loses/the curve nylon guide rail straight, causes the link joint when the transportation maintains parallel, steady.

链板输送机采用塑钢链板或不锈钢链板连接而制作，从而可根据要求达到若干长度的输送，机架中安装直输/转弯尼龙导轨，使链板在输送时保持平行，平稳。

Uses models the steel link joint or the stainless steel link joint connection manufactures, thus may achieve certain lengths according to the request the transportation, in the rack installs loses/the curve nylon guide rail straight, causes the link joint when the transportation maintains parallel, steady.

链板输送机采用塑钢链板或不锈钢链板连接而制作，从而可根据要求达到若干长度的输送，机架中安装直输/转弯尼龙导轨，使链板在输送时保持平行，平稳。

Other methods can only give approximate values. The presented method can be used in any roller chain drive where the two sides of the chain are straight.

非线性方程法可用于参数是任何值的链传动，可计算出链轮在任何位置时的链传动中心距，且可计算链传动中心距的最大值和最小值，是精确计算链传动中心距的方法之一。

Neither the killing of Mr Zarqawi nor any breakthrough on the political front will stop the insurgency and the fratricidal murders in their tracks.

在对危险的南部地区访问时，他斥责什叶派民兵领导人对中央集权的挑衅行为。

In fact,I've got him on the satellite mobile right now.

实际上 我们已接通卫星可视电话了