查询词典 main

A detailed analysis of the main circuit introduction, control method and working principle of the direct-drive wind energy conversion system are given to introduce the two important parts a of this paper: First part is the control method of the multiple boost convertor, the important instantaneous current control method of this paper is given through the analysis of the main circuit structure, control method and working principle. Then a steady-state analysis for low-frequency, a high-frequency component analysis, and a closed-loop tracking performance analysis for dynamic response are provided to analyze the method proposed; And the second part is the control method of invertor.

在系统变流器整体结构分析的基础上，引出本文重点研究的两个变流环节的控制：第一部分是系统升压斩波器的控制，通过分析相关主电路结构、原理，建立了数学模型，引出本文重点研究的瞬时值控制策略的概念和具体实现，并对升压斩波器的瞬时值控制策略进行了详细的高频、低频模型分析和稳态、动态性能分析；第二部分是系统并网逆变器的控制，通过对逆变器主电路的数学建模和控制要求分析，研究了并网逆变器的瞬时值控制策略，包括电感电流控制内环和直流电压控制外环的具体设计和实现方法。

This paper mostly presents the Ironworks' main work achievements in technical and management innovation s in recent years,strengthened moves in independently scientific and technological innovation and deepened enterprise management,further put forward the Ironworks' train of thought in innovation and main points of work for the next period.

主要介绍了炼铁厂近年来在技术创新、管理创新方面取得的主要工作成绩，以及加强科技自主创新、深化企业管理的举措，进一步提出了炼铁厂今后一个时期的创新工作思路及工作重点。

The main research methods are:(1)Theory analysis:from the 2D plane geometry analysis, dots continuity characteristics are found. The first time irrational fraction algorithm is used in FM program.(2)Experiments reaearch:experiments of condition halftone function are designed under the cross-experiment principles. The first time variable information printer and C# language are used in experiment.(3)Data processing:new type digital density apparatus is used to measure data. Compare is used in processing data and error cause are explained. The main works as follows:The dot area percentage has been gained and new condition halftone function has been set up.(2)After being corrected, speed of irrational fraction algorithm has been compared with multiplicative congruence algorithm's.

本文的主要研究方法有：(1)理论分析：运用数字加网原理，从二维平面几何分析入手，借助实验验证研究网点连续特性；首次系统地把无理数取尾法随机数生成器引入到调频加网系统中，根据实验修正生成器的模型，运用统计假设检验理论，对生成的随机数序列进行统计假设检验；(2)实验研究：根据正交实验法则设计实验，首次采用可变信息印刷机(HP Laser PS印刷机)输出实验样张，克服了用传统胶印机作实验影响因素多的缺陷；采用新型数字式密度仪测量密度值，提高了数据精度；采用最新编程语言编写调频加网程序；(3)数据处理与分析：利用平均值比较法处理数据，对误差产生的原因进行讨论。

The reference crop evapotranspiration(ET0) in Guanzhong region was calculated with the Penman-Monteith equation. The change characteristics of meteorological factors and ET0 over year were analyzed. The regressing relation between ET0 and geography factors was established. Space distribution of ET0 based digital elevation model was obtained. The water consumption model of main cropes was established using the crop cofficient method. The irrigation water requirement of main crop and it's space distribution based DEM under the different precipitation probability was obtained, which advanced the calculation precision of ET0 from spot scal to regional scal. The concept of water consumption under the irrigational scal was proposed. The water consumption model of different water user and model of groundwater balance based on the water consumption of Baojixia irrigation district was established. Which can refects the relation between water utilization, water consumption and change amount of groundwater resouces.

深入分析了关中地区气象要素的变化趋势，用Penman-Montainth 公式计算了参考作物蒸发蒸腾量（ET0），建立了ET0与地理要素的多元回归关系，获得了基于数字高程模型DEM的关中地区ET0的空间分布图；用作物系数法建立了关中主要作物生育期耗水模型，获得了主要作物在不同降雨条件下的灌溉需水，以及基于DEM的主要作物灌溉需水空间分布图，提高了作物蒸发蒸腾量由点到面尺度转换过程中的估算精度；界定了灌区尺度的耗水量的概念，包括用水耗水和非用水耗水，建立了灌区耗水量计算模型及基于耗水量变化的浅层地下水均衡模型，能较好地反映灌区引水量、耗水量及地下水蓄变量之间的内在关系。

Analyzing the relation between earthquake and structure distortion, main fault belt, crust, upper mantle, ground fracture, hotspring, geotherm, conductance frame, stress state in Guanzhong area is analyzed with earthquake mechanism, isoseismal line, crustal stress measure, fault displacement measure, and simulating test results. Earthquake formation mechanism is discussed with dynamics mechanism in Guanzhong base. There are 3 forces and a good medium environment, which are main reasons caused earthquake happened in Guanzhong area. The first force is NE and NEE level extrusion one which is parallel with long axis of Guanzhong base. The second one is level strain which is vertical with long axis of the base.

对地震与构造形变、主要断裂带、地壳及上地幔、地裂缝、温泉和地热、电性结构等关系进行了分析研究，通过震源机制解、地震等烈度线、地应力测量、断层位移测量及模拟试验等成果，分析了关中地区的地应力状态，从关中盆地的动力学机制，对该区的地震成因机制进行了探讨，认为与关中盆地长轴平行的NE和NEE向的水平挤压力、与盆地长轴方向垂直的水平张力及地幔上涌力三组力的作用，加之壳内高导层这一有利的介质环境，是导致关中地区地震发生的主要原因。

The main hall usually contains alter for praying to the gods and the worship of ancestors. The two sided of the main hall is the oldest father's room. The ells are the place where the juniority to live, if the population keepsincreasing then the ells can extend. The youngest have to live in the newest house and the newest should be shorter than the others. It represents the order and respects them.

正厅﹝俗称横屋﹞供奉祖先的排位，正厅左右两侧房间是辈分最长者的居处；厢房则为子孙辈居住的，若子孙陆续繁衍，厢房可向后延伸扩建，辈分低者住在新的房舍，且新建房舍不可高过旧屋，表示「长幼有序」的精神。

The thesis contains five chapters. The first chapter summarizes the development and research of switched reluctance drive, discusses the main research direction, and explains the main work in this paper. In chapter 2, hardware system which includes the design of power converter and various control circuit is discussed. TMS320LF2407 DSP is used to design the hardware circuits of SRM control system, and design details including the current detection, position sensing, fault protection, speed detecting, keyboard and display etc. are provided. Because of the full use of the abundant peripheral resources of DSP, it comes to the aim simplifying the circuit structure and heightening the reliability. In chapter 3, the application of neural network on SRM control system is introduced, a new the application of neural network and the method of sampling is proposed and a simulation system based on Matlab/Simulink is established. Chapter 4 discusses the routine designing issue. Because the modularized programming method is adopted, and multi-interrupt processing technique is used, operation efficiency of the control software is highly raised. At last, the foregoing SRM control system is tested. Speed adjustment is realized, and other targets on the research and design of SRM control system are reached, which establishes a good foundation for further research.

本文共分五章，第一章概述了开关磁阻电机调速系统(Switched Reluctance Drive，简称SRD)及其发展和研究现状，论述了其主要研究方向，并说明了本文的主要工作；接下来的一章主要讨论了SRM的硬件系统，主要包括功率变换器的设计和各种控制电路的设计，本文以TMS320LF2407为核心设计了开关磁阻电机控制系统硬件电路，给出了包括电流检测、位置检测、故障保护、测速电路及键盘和显示电路等部分电路的详细设计，充分利用了DSP的丰富外设资源，达到了简化电路结构、提高运行可靠性的目的；第三章介绍了人工神经网络在开关磁阻电机控制系统中的应用，提出了一种新的应用方式(利用GPFN神经网络调节PI参数)以及如何采取样本，搭建了基于Matlab/Simulink的仿真系统；在第四章中，讨论了开关磁阻电机控制软件的设计，采用模块化编程方法，采用基于多中断的控制程序，提高了控制软件的效率；最后，对所设计的开关磁阻电机控制系统进行了实验，实现了电机调速，达到了开关磁阻电机控制系统研究和设计的预期目标，为更近一步研究打下了基础。

In Tibetan Buddhism, the main art form of painting--thang kha techniques and materials for the main study, but also essential to involve the art form and aesthetic subjects.""

本文以藏传佛教艺术中最主要的绘画形式——"唐卡"的技法材料为主要研究对象，同时也必不可少地涉及到其艺术表现形式和审美意蕴。

Generally the transformer substation must install 2~3 main transformers; when 330 kilovolt and below, the main transformer usually uses the three-phase transformer, its capacity according to puts into 5 ~10 year anticipated load choices.

一般变电所需装2～3台主变压器；330 千伏及以下时，主变压器通常采用三相变压器，其容量按投入5 ～10年的预期负荷选择。

In fact it is the only main road in this area and some 5,000 displaced people who live right in that immediate vicinity have fled their homes and many of them are moving toward Uvira, which is one of the main regional centers in South Kivu.

他说：事实上，它是唯一的主要道路在这方面，有些5000谁生活在附近的权利流离失所人逃离家园，其中不少是toward乌维拉，这是在南基伍地区的主要中心之一动。

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。