系统的

In this paper, the basic principle and the power factor of conventional SERDS are discussed. Aiming at its shortage of low power factor, boost chopper type SERDS is adopted. The equivalent circuit of the new scheme is built up, and then vector diagram is used to analyze the power factor of the system, also the harmonic distortion of the system is discussed. The experiment device is established base on a 380F/7.5 kW induction motor and a passive soft switching scheme is applied in order to improve the working condition of IGBT. At last, the experimental results are shown.

本文在分析传统串级调速原理的基础上，对系统的功率因数进行分析；针对传统串级调速系统功率因数低的缺点，采用升压斩波式串级调速系统加以改进；建立了升压斩波式串级调速系统的等效电路并采用向量图法对该系统的功率因数进行详细分析；分析了系统的谐波情况；构建了以7.5kW／380V电机为调速对象的升压斩波式串级调速系统实验装置，给出相应的实验结果；针对斩波器中IGBT处于硬开关状态的缺点，应用无源无损软开关技术予以改善，包括对软开关电路工作原理的分析、参数的设计并给出相应的实验结果。

This paper introduces air conditioning schemes for villadom , such as rooftop air-cooled packaged air conditioning system, air-cooled heat pump plus water chiller option, the split system with the air-cooled heat pump.

介绍了可用于别墅建筑的冷风式成套热泵空调机组系统、风冷热泵冷水机组系统、风冷式热泵分体空调系统等供暖制冷系统的方案，并指出应根据不同的能源和气候条件，选择合适的系统，以满足用户和房地产商的利益要求。

cti-based water-power information system is an interactive voice response system using the voice server model.

基于cti的水电信息系统是一个采用声音服务器模型的交互式语音应答系统；深入的分析了水电信息系统的需求，给出了系统功能和系统结构图，绘制了语音子系统的工作步骤，给出了系统数据库的总体设计，同时给出了语音子系统与数据库交互的函数接口，较好的完成了远程汇报，查询和管理水电信息的任务。

Computer technologies including interruption technology, DMA technology, EMS technology and XMS technology are integrated in the system. The two key problems, real time multi-task processing and multi-circle uninterrupted measuring are effectively solved. Owing to the adoption of objectoriented technology, the software structure of the developing system is greatly simplified. As a result, the developing efficiency of the software is greatly improved.

本研究初步完成了电控开发系统的开发，该系统利用PC机和通用功能板等标准硬件，并开发了测控接口板和功率驱动板等专用部件，使所开发的电控开发系统具有开放式和组合式结构，减少了电控开发系统的成本，并使其具有很好的适应性和发展性，通过综合运用中断技术、DMA技术以及EMS和XMS技术等多项计算机技术，使电控开发系统不仅具有了ECU的功能，而且还具有多参数多循环同步测量和实时人机交互处理等能力。

The function is proved to be positive and its different sign can not be changed.By applying this method to the Y_series made in China,it can meet the needs of the industry driver system. different geometry ; two_order system ; variable gradient method ; alterate current induction motor stability function

在工程领域中，具有稳定特性的传动系统是非常需要的，当然，最好能够在系统运行前就能够判断出系统的稳定性区域，以便在设计系统的控制方法和选择系统控制量的时候能够避免系

In theory, firstly, the numerical simulation methods, such as the boundary element method, the finite difference method and the finite element method, were utilized to calculate the distribution of electric field intensity and potential of the electron-gun system, the focusing system and the whole equipment, respectively. Then, the trajectories of the electron-beam were traced by using of the Runge-Kutta method and the Monte-Carlo method associatively. The point spread function was also calculated.

在理论分析中，先后采用边界元方法、差分方法、有限元方法等科学数值计算方法，编制程序，对X射线源的电子枪发射系统、聚焦系统以及发射系统与聚焦系统的组合系统等的电场分布进行了严格的计算，在准确求得各系统电场内各个剖分点的电场场强、偏导数等参量的基础上，采用蒙特-卡罗模拟方法和不等距龙格-库塔方法相结合，追踪由LaB_6单晶阴极表面发射出的大量电子束在电场内的运动轨迹，求出点扩展函数，并根据点扩展函数的优劣，反复调节、大量计算对比，挑选出X射线源最佳的电极结构及其组合。

The achievement of this project can be briefly summed up as following:(1)the carbon contributing to karst processes mainly comes from ecological system itself under the condition of existence of vegetation and soil covers;(2)results indicates that the depositing processes of rainfall to CO2 is an important "sink" to global carbon cycle;(3)owing to the differences of vegetation and surface covering, the adjusting effect of ecosystem to environmental humidity, temperature and CO2 concentration near surface air which indicates different benefit of preventing water and soil from lose is marked;(4)the preponderant species of vegetation in the karst ecosystems which have different kinds of carbonate rocks are obviously variant, and this situation results to the clearly differences of the micro － habitat , structure of surface cover and water holding capacity;(5) the relevant study showed that the carpophagous animals and birds make a important role in the spreading of vegetation seeds. The designed experience for the study of seed reservoir was not able to obtain a satisfactory result.

主要研究成果包括：通过对表层系统碳库的研究，认为在有土壤和植被覆盖时，岩溶作用过程中的碳主要来自生态系统本身而不是母岩；降雨对大气碳具有重要&沉淀&作用，是碳的一个重要汇；不同植被类型表层岩溶系统对系统水份、空气湿度、气温、土温和近地表 CO2浓度等具有明显调节作用，具有不同的水土保持效益；不同母岩的岩溶生态系统的植被优势种、属差异明显，由此形成的小生境、地被物及其持水性差异巨大；对典型岩溶表层系统种子库的试验研究没有取得满意结果，但食果动物、鸟类对种子传播起到一定作用。

The spatial analysis is an important component of GIS and distinguishes GIS from the general cartographic system and management information system . The spatial analysis performance is an important performance of GIS .

空间分析是地理信息系统的一个极其重要的组成部分，是地理信息系统区别于一般的制图系统和信息管理系统的根本所在，其性能是地理信息系统的性能的重要标志。

For solving the Y2K problem, many large-scale overseas or home enterprises used ERP system to replace the old system in their enterprise. Many enterprises even used it as the foundation of electronic enterprise ,and integrated other information systems into it. However the organizational performance is not necessarily good. Some scholars think the performance of ERP will be influenced by the time length after ERP go-live and the different performance targets. Ross even thought the performance of ERP will assume a "V" path when improvementing an ERP,and get continuate improvement. Therefore this research is for discussing whether the ERP system can improve organizational performance. It used the different performance targets to evaluate the long-term organizational performance that ERP system brought.

摘要 在千禧年Y2K的推波助澜下，国内外许多大型企业纷纷使用企业资源规划(Enterprise Resource Planning，ERP)系统来取代企业内部的旧系统，甚至许多企业将ERP系统当作企业电子化的基础，进一步整合其他的资讯系统，但是不一定都能有好的绩效结果，因此有学者认为ERP绩效会受到系统上线后的时间长短或效益衡量标的的影响而改变，ROSS学者甚至认为ERP系统的绩效甚至会在上线后呈现V字型的改善路径，并且会呈现持续改善的状况。

It makes an all-round research, analysis and study to it with the extinctive theory, planning demand and systemic conservation of FM-200, including the design for automatic alarm systems and some essential claim for safety decentralization and the economy budget for the whole system.

本文根据深圳高阳万国电脑有限公司通讯楼的具体工程概况，采用全淹没式七氟丙烷（FM-200）灭火系统对其进行保护，同时对目前哈龙灭火系统替代产品的灭火性能、使用场所及对环境与人身安全影响进行了分析，对七氟丙烷（FM-200）气体灭火系统的灭火机理、设计要求以及系统维护进行了全面的调查、分析与研究，包括自动报警系统的设计和一些必要的安全疏散要求以及对系统的经济预算，完成了本文设计。

I can not make it blossom and suits me

我不能让树为我开花

When temperatures are above approximately 80 °C discolouration of the raceways or rolling elements is a frequent feature.

当温度高于 80 °C 左右时，滚道或滚动元件褪色是很常见的特征。