矢量

Is a vector dot product.

是矢量的点积。

Since scalars are independent of the coordinate system, the dot product of two vectors is called a scalar invariant

因为标量与坐标系无关，故两个矢量的点积称为标量不变量。

ABSTRACT: A Rockwell PowerFlex7000 Variable Frequency Drive is used in JiuZHou Electric medium voltage drive test bay as the converter. Because of it belong to the current source drive, it has the function of the four quadrant, it can achieve the energy feedbackmake the motor brake,also has the advanced vector control technology, so it can achieve all kinds of load test, there are no other drives can replace it in simulate motor load. PowerFlex7000 drive has ability to achieve the full load test before the drive leave factory.

摘 要：罗克韦尔PowerFlex7000变频器在九洲中压变频实验站测试系统中作为变流逆变器使用，由于本身属于电流源型变频器，具有四象限运行功能，能够实现能量的回馈和对电机的制动，先进的矢量控制技术，可以实现各种复杂多变的负载特性，在模拟电机负载方面起到了其他变频器无可替代的作用，实现了变频器出厂之前的满负荷测试。

The structure of knowledge base for mechanism kinematic schemes, screw theory and dual vector representation are introduced briefly.

简要介绍了机械运动系统方案设计知识库的结构和螺旋理论及对偶矢量表达。

The topology of two-stage matrix converter given based on the concept of fictitious DC link of matrix converter and dual space vector modulation strategy of TSMC was studied.

在矩阵变换器虚拟直流环节的思想上，给出了双级矩阵变换器的电路拓扑，仿真研究了双级矩阵变换器的双空间矢量调制策略。

In order to improve the modernization and convenience of communication network,the given design and key applied technologies of management system based on GIS,which is about long-distance communication trunk transfer network,take advantage of vector maps and dynamic data exchange of GIS.

为提高通信网管理的现代化和易用性，利用GIS系统的矢量地图和属性数据动态交互的优势，给出了基于GIS的长途通信干线传输网络管理信息系统的设计方案及其关键的实现技术，从而很好的解决了长途通信干线网络资源的地域性和空间性难以描述的问题，大大增强了系统的操作性和信息表现能力。

It realizes dynamic store and management of mining data and finishes inputting of mining data,3D visualization of mining area,establishing model of terrain surface,inquiring and analyzing spatial data,collection of DEM vector and image and so on.More convenience will be bring to mining manager.

系统实现了对矿业数据动态存储和管理，可完成矿业数据输入、矿区三维可视化、地形表面建模、矿区空间查询分析、DEM矢量影像数据集成等功能，必将给矿业管理工作者带来很大方便。

In order to change ability of weaker sustainable development of Three gorges reservoir area, instability of ecology, promotion effectuation strategic objective of land sustainable use in Three gorges reservoir area, it is necessary to integrated control present situation , potentiality of land use and driving forces of land use change, to search main obstacle on land use, to research and analyse

取得以下主要结果及结论： 1、通过图件、数据资料的收集，并结合2005年53个乡镇的土地利用实地变更调查，在landstar软件的支持下，采用图形扫描、矢量化和属性录入的方法建立了三峡库区万州土地利

The dielectric discontinuities in waveguides Eire analysed by finite element method in combination with perfectly matched layers.

本文将矢量有限元法与完全匹配层相结合对波导介质不连续性问题进行分析。

In this paper, we present a frequency conversion electromotor system organized by voltage vector transducer and induction-motor.

本文研究了用电压矢量变频器和感应电动机构成的变频电动机系统。

We have no common name for a mime of Sophron or Xenarchus and a Socratic Conversation; and we should still be without one even if the imitation in the two instances were in trimeters or elegiacs or some other kind of verse--though it is the way with people to tack on 'poet' to the name of a metre, and talk of elegiac-poets and epic-poets, thinking that they call them poets not by reason of the imitative nature of their work, but indiscriminately by reason of the metre they write in.

索夫农 、森那库斯和苏格拉底式的对话采用的模仿没有一个公共的名称；三音步诗、挽歌体或其他类型的诗的模仿也没有——人们把&诗人&这一名词和格律名称结合到一起，称之为挽歌体诗人或者史诗诗人，他们被称为诗人，似乎只是因为遵守格律写作，而非他们作品的模仿本质。

The relationship between communicative competence and grammar teaching should be that of the ends and the means.

交际能力和语法的关系应该是目标与途径的关系。