查询词典 System

In this article two functional modes of the Fly-back Converter (Continuous Conduct Mode and Discontinuous Conduct Mode) are particularly analyzed, which include their characteristics, applications, the critical pattern of two functional modes is argued, both the exact boundary from the angle of circuit parameters is crystallized, at the same time, basic principle of PFC under the DCM mode is introduced, which settle theoretical basis for the subsequent design; by establishing the mathematic model of the converter, a further investigation of the configuration is made, qualitatively and quantitatively, analyzed to settle exactly theoretical basis for the subsequent emulation and the experimental parameter; from the angle of steady-state analysis, the transfer function of the system is deduced to establish dynamic small-signal state equation, emulating the system with the help of matlab, then according to the simulation result and the theory of PFC revise the system, lastly, we adopt the project which add a zero-pole compensator to the voltage loop, by this way, a satisfied system performance is gained and the PFC scheme is ensured successfully; finally, based on the previously-done work, we combining with the situation of specific design requirement, acquired the numerical value of each unit devices in this converter

详细分析了反激式变换器的两种工作状态，连续模式(Continuous Conduct Mode ，简称CCM)和断续模式(Discontinuous Conduct Mode，简称DCM)以及各自的特点、应用场合，论证了两种工作状态的临界模式，从电路参数的角度明确了二者的界限，同时还介绍了DCM模式下PFC的基本原理，为后面的设计奠定理论基础；通过对整个变换器系统建立准确的数学模型，对此变换器的电路结构做了进一步的研究，定性、定量地分析了变换器各部分的工作状态，为仿真和实验参数的确定以及电路参数的优化提供理论依据；从稳态分析的角度，为系统建立了动态小信号状态方程并推导出系统的传递函数，利用matlab对系统进行仿真，进而根据仿真结果以及PFC的相关理论对系统进行校正，采用在电压环加入零点—极点补偿器的设计方案，得到了满意的系统特性并且保证了PFC的顺利实现；最后，在前面所做工作的基础上，结合设计要求计算出此变换器系统中每个元器件的数值，利用Pspice对其进行了仿真、优化，然后根据仿真结果搭建了硬件电路。

Laboratory equipment managements system is a typical management information system, the system is a software system that adapts to the urgent need of management of laboratory equipments to school, the development including two aspects, one is the establishment and maintenance of the background database , the other is the development of fore-end application. After analysis and comparison, we decide to use ASP and SQL as the development to

实验室设备管理系统是一个典型的信息管理系统，本系统是一个为适应对学校实验室设备管理的迫切需求而设计开发的软件系统，其开发主要包括后台数据库的建立和维护以及前端应用程序的开发两个方面，经过分析和比较，我们决定使用ASP和SQL作为开发工具，利用其提供的各种面向对象的开发手段，尤其是数据窗口这一能方便而简洁操纵数据库的智能化对象，首先在短时间内建立系统应用原型，然后，对初始原型系统进行需求迭代，不断修正和改进，真到形成用户满意的可行系统。

In this study, the architecture of the remote alert system is:(1) the inner controller of the factory mechanical equipment connects to the webpage control server,(2) the webpage control server conveys the operation state of the equipment controller to the remote alert system by the network,(3) the fore-end process module of the alert system receives the equipment abnormal messages, according to the user define parameters, the rear-end process module of the alert system issues the alert.

本研究之示警系统架构为：(1)工厂机械设备之内部控制器接至网页控制伺服器，(2)网页控制伺服器经乙太网将设备控制器之重要运转态传送至示警系统伺服器，(3)示警系统之前置处模组接收设备常资讯，并依据设定之服务，调阅系统中引模组，并透过系统之讯息执模组进警示资讯的发布。

College Teacher Management Information System is a typical information management system. The basic information management and the query system is one of the foundation part of the whole system.The procedure's development includes the establishing and maintenance of backstage database and the forepart application two aspects.

高校教师管理系统是典型的管理信息系统，系统中的基本信息管理及查询子系统是整个系统的基础部分之一，其开发主要包括后台数据库的建立和维护以及前端应用程序的开发两个方面。

College Teacher Management Information System is a typical information management system. The basic information management and the query system is one of the foundation part of the whole system.The procedure's development includes the establishing and maintenance of backstage database and the forepart application two asp ects.

高校教师管理系统是典型的管理信息系统，系统中的基本信息管理及查询子系统是整个系统的基础部分之一，其开发主要包括后台数据库的建立和维护以及前端应用程序的开发两个方面。

Especially in the field of military , infrared small moving target detection technology holds an important position in advanced weapon system of Occident, including forewarn system of aeroplane carrier, infrared searching and tracing system of varies airplanes, infrared imaging guidance missile and warning system of some ground military facilities.

尤其在军事领域，目前在欧美国家的一些先进的武器系统，包括航空母舰的预警系统、各种飞机的红外搜索跟踪系统、红外成像制导导弹和一些地面军事设施的告警系统中，红外弱小目标的检测技术的地位举足轻重。

On the base of the analysis of the safety situation and the safety evaluation,this paper put forward that the mine produce system is constituted by person,thing and environment,and the system is complex disaster three-dimensional system in space distributing.So Mine safety evaluation ought to be established in person,thing and environment,and then analyze and judge on mine safety system from the danger factor,the safety evaluation index,the frame model of safety evaluation and the comprehensive evaluation m...

本文在分析我国矿山安全生产严峻局势和矿山矿井安全评价国内外现状的基础上，提出矿山井下生产系统是一个由人、机、环境三方面所组成的、空间分布极其复杂的灾害系统，其安全评价应立足于人、机、环境三方面进行系统的分析与判断，并从危险因素、安全评价指标及权重、隶属函数、安全评价结构模型、综合评价方法等方面出发，以掌握矿山矿井系统的安全状态，为矿山安全管理体系的整改提供依据。

On the design of index system, this paper introduces the idea of BSC to design the frame of index system, to explain the index system from the four dimensions of finance, custom, management, and development. The basal indexes of each dimension is filtered in the way of partial correlate of these indexes and EVA form the point of view of validity andindependence, and gets well indexes to make up the index system of Advanced Professional Executives performance evaluation.

在此框架下提出企业所有者对高级职业经理人绩效考核指标体系的设计模式，用平衡记分卡构建备选指标的框架，分别从财务维度、客户维度、内部营运维度、个人维度四个方面来考核高级职业经理人的绩效，在备选指标的基础上，运用相关性理论来考察指标的有效性和独立性，筛选出有效的指标构成高级职业经理人的绩效考核指标体系，保证绩效考核指标体系设计的科学性、合理性与简洁性。

The extrude characteristics of intelligent base station are its independent working and being a user for main franking system (common franking system, difference from Intelligent base station) when intelligent base station System communicate with other main franking system.

智能基站的突出特点是既可以独立运行，又可以作为主集群系统(其它集群系统，区别于智能基站)的终端进入主集群系统。

The extrude characteristics of intelligent base station are itsindependent working and being a user for main franking system(common franking system, difference from Intelligent base station)when intelligent base station System communicate with other mainfranking system.

智能基站的突出特点是既可以独立运行，又可以作为主集群系统(其它集群系统，区别于智能基站)的终端进入主集群系统。

When this condition occurs, inbound replication with the source partner is stopped on the destination domain controller and event ID 2042 is logged in the Directory Services event log.

计算机密码学是研究计算机信息加密、解密及其变换的科学，是数学和计算机的交义学科，也是一门新兴的学科。

Instructions: click on the thumbnails to see a larger image, then use the left-right arrow keys to scroll through the slideshow.

使用说明：滑鼠点在小图上即可放大观赏。开启后键盘左右键可用来换照片。