基于SSH的web技术介绍外文翻译

基于SSH的web技术介绍外文翻译
基于SSH的web技术介绍外文翻译

毕业设计外文资料翻译

题目名称:基于SSH的web技术介绍

学院:计算机科学技术学院

专业年级:网络工程12级

学生姓名:冯金明

班级学号:2班4号

指导教师:邵珠富

二○一六年四月三十日

译文题目:基于SSH的web技术介绍

原文题目:SSH based web technology introductio

原文出处:https://www.360docs.net/doc/be11612805.html,/view/7c5f2560f5335a8102d22073.html

SSH based on Web Technology

1、Introduction

One preface along with the Java technique of gradual mature and perfect, Be establishment business enterprise class application of standard terrace, the J2 EE terrace got substantial of development .Several technique asked for help from to include in the J2 EE norm : Enterprise JavaBean (EJB), Java Servlets (Servlet), Java Server Pages(JSP), Java Message Service(JMS)...etc., development many application system.But, also appeared some problem in the tradition J2 the EE the application of the development the process:

1)the antinomy of of data model and logic model. Currently the database of usage basically and all is relation type database, but the Java be essentially a kind of the language which face to object, object at saving with read usage SQL and JDBC carry on a database operation and lowered plait distance of efficiency and system of can maintenance;

2)tradition of J2 EE application much the adoption is according to the EJB heavy weight frame, this kind of frame suitable for develop a large business enterprise application, but usage the EJB container carry on development and adjust to try to need to be waste a great deal of time.For lowering the Ou of code to match sex, exaltation system of development efficiency, this text put forward 1 kind EE according to the J2 of the Struts frame and Spring frame and the Hibernate frame application development strategy.

2、Use the Struts realization MVC structure

use the Struts realization MVC structure MVC(Model-View-Controller) is put forward by the Trygve Reenskaug, first drive application in the environment SmallTalk-80, is many to hand over with each other with interface system of

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constitute foundation. According to the need of variable of the interface design, MVC hand over with each other constitute of system to resolve into model and see diagram, controller three part. Model(Model) is software processing problem logic at independence in outside manifestation under contents and form circumstance of inside abstract, packed the core data, logic of problem and function of calculation relation, independence in concrete of interface expression and I/O operation. See diagram(View) mean information and particular form demonstration of model data and logic relation and appearance to the customer. It acquire a manifestation information from the model, there can be many for homology of information dissimilarity of manifestation form or see diagram. The controller(Controller) is a processing the customer hand over with software with each other operation of, its job is control provide model in any variety of dissemination, insure a customer interface among the model of rightness should contact; It accept a customer of importation, give°the importation feedback model, then realization compute model control, is make model and see diagram to moderate work of parts. Usually 1 see a diagram rightness should a controller. Model, see separate of diagram and controller, make a model be able to have many manifestation to see diagram. If the customer pass a certain see the controller of diagram change the data of model, all other dependence in these see of data diagram all should reflection arrive these variety. When therefore and regardless occurrence what data variety, controller all would variety notice ally see diagram, cause manifestation of renewal. This is actually a kind of variety of model-dissemination mechanism.

The Struts frame is to be the item of Apache Jakarta to constitute part to publish luck to do at the earliest stage, it inherited MVC of each item characteristic, and did according to the characteristics of J2 EE correspond of variety with expand. The Struts frame was good to combine Jsp , Java Servlet , Java Bean, Talia etc. technique. In the Struts, what to undertake the controller role in the MVC be an ActionServlet. The ActionServlet is an in general use control module. This control module provided a processing all HTTP claim which send out Struts of entrance point. Its interception with distribute these claim to arrive correspond of action type.(these action all of type

is Action son type)Moreover the control module is also responsible for using to correspond of claim the parameter fill Action Form(FromBean), and pass action type(ActionBean).Action type the business logic of the interview core, then interview Java Bean or adjust to use EJB. End action type control the power pass follow-up of JSP document, from JSP document born see diagram. All these control logic make use of Struts-config.xml the document come to allocation. See diagram in the Struts frame main from JSP born page completion, the Struts provide abundant of JSP label database, this is advantageous to separating performance logic and procedure logic.The model is with 1 or the form existence of several Java Bean. In the Struts, main existence three kinds of Bean, respectively BE: Action, ActionForm, EJB perhaps Java Bean. The Struts frame have no concrete definition model layer of realization, in actually the development, model layer usually is close with business logic connect with each other, and want to carry on operation to the first floor data. The underneath's introduction is a kind of development strategy, lead the Hibernate into the model layer of Struts frame, usage it to carry on a data to pack with reflect to shoot, provide hold out for long time turn of support. 4 usage Hibernate and the Struts development J2 EE application 4.1 system structure diagram 3 manifestation according to Hibernate and Struts development strategy of system structure diagram.

3、Spring the Application Framework

Spring isn't particularly a web framework but a generic lightweight application framework with dedicated web support, and show the architectural differences to Struts and WebWork .In contrast to Struts or WebWork, Spring is an application framework for all layers: It offers a bean configuration foundation, AOP support, a JDBC abstraction framework, abstract transaction support, etc. It is a very non-intrusive effort: Your application classes do not need to depend on any Spring classes if not necessary, and you can reuse every part on its own if you like to. From its very design, the framework encourages clean separation of tiers, most importantly web tier and business logic: e.g. the validation framework does not depend on web

controllers. Major goals are reusability and testability: Unnecessary container or framework dependencies can be considered avoidable evils.

Of course, Spring's own web support is nicely integrated with the framework's general patterns. Nevertheless, replacing the web solution with Struts, WebWork, or the like is easy. Both with Spring's web support or a different one, Spring allows for building a true dedicated middle tier in the web container, with the option to reuse exactly the same business logic in test environments or standalone applications. And within J2EE, your business logic will not unnecessarily depend on container services like JTA or EJB - allowing complex, well-architected web applications to run in a "simple" container like Tomcat or Resin.Note that Spring doesn't generally aim to compete with existing solutions. It rather fosters seamless integration with standards like Servlet, JSP, JTA, JNDI, JDBC, and JDO, and well-suited tools like Hibernate, Velocity, Log4J, and Caucho's Hessian/Burlap. The framework is designed to grow with the needs of your applications, in terms of technology choice: For example, you will probably use JTA via Spring's JtaTransactionManager if you need distributed transactions - but only then, as there are perfect replacements for single databases, like DataSourceTransactionManager or HibernateTransactionManager.

4、The Design of Spring's Web Framework

Spring's web framework is designed around a DispatcherServlet that dispatches requests to handlers, with configurable handler mappings, view resolution, and locale and theme resolution. The default handler is a very simple Controller interface, just offering a "ModelAndView handleRequest(request,response)" method. This can already be used for application controllers, but you will prefer the included implementation hierarchy, consisting of AbstractController, AbstractCommandController, MultiActionController, SimpleFormController, AbstractWizardFormController. Application controllers will typically be subclasses of those. Note that you can choose an appropriate base class: If you don't have a form, you don't need a FormController. This is a major difference to Struts.

You can take any object as command or form object: There's no need to implement an interface or derive from a base class. Spring's data binding is highly flexible, e.g. it treats type mismatches as validation errors that can be evaluated by the application, not as system errors. So you don't need to duplicate your business objects' properties as Strings in your form objects, just to be able to handle invalid submissions, or to convert the Strings properly. Instead, it's often preferable to bind directly to your business objects. This is another major difference to Struts which is built around required base classes like Action and ActionForm - for every type of action. Compared to WebWork, Spring has more differentiated object roles: It supports the notion of a Controller, an optional command or form object, and a model that gets passed to the view. The model will normally include the command or form object but also arbitrary reference data. Instead, a WebWork Action combines all those roles into one single object. WebWork does allow you to use existing business objects as part of your form, but just by making them bean properties of the respective Action class. Finally, the same Action instance that handles the request gets used for evaluation and form population in the view. Thus, reference data needs to be modelled as bean properties of the Action too. These are arguably too many roles in one object.Regarding views: Spring's view resolution is extremely flexible. A Controller implementation can even write a view directly to the response, returning null as ModelAndView. In the normal case, a ModelAndView instance consists of a view name and a model Map, containing bean names and corresponding objects (like a command or form, reference data, etc). View name resolution is highly configurable, either via bean names, via a properties file, or via your own ViewResolver implementation. The abstract model Map allows for complete abstraction of the view technology, without any hassle: Be it JSP, Velocity, or anything else - every renderer can be integrated directly. The model Map simply gets transformed into an appropriate format, like JSP request attributes or a Velocity template model.

5、Hibernate the Application Framework

Data's holding out for long time layer and Hibernate is one piece according to

hold out for long time layer frame, is a kind of realization object and relation of the tool which reflect to shoot(O/R Mapping), it carried on the object of the lightweight to pack to the JDBC and make procedure member can usage object plait distance thought to operation database. It not only provided to shoot from Java to reflect of data form, but also provided a data a search and instauration mechanism. Opposite in usage JDBC and SQL to operation database, use Hibernate ability consumedly of exaltation realization of efficiency. The Hibernate frame use allocation document of the form come to the reflect of the definition Java object and data form to shoot relation, in the meantime at more deep of level of data form of relation explanation for the relations such as inherit of and containment etc. of Java object. Pass the usage HQL language sentence complications of relation the calculate way use the way of object description, to a large extent simplification logarithms according to of search, speed development of efficiency. Have in the Hibernate a simple but keep the API of view, used for to the database mean of object performance search. Want to establish or the modification be these objects, need in the procedure carry on with them to hand over with each other, then tell Hibernate to keep. So, a great deal of pack hold out for long time turn operation of business logic no longer demand write a trivial JDBC language sentence, make data last long thus the layer got biggest of simplification.

6、Use Hibernate and Struts to develop J2EE application

Development practice underneath combine a development practice, with in the J2 the EE the application very widespread customer register process for example, elucidation above-mentioned system structure is how concrete usage. The process of register is very clear: Customer from register page login.jsp importation register information, system to register the information carry on verification, if exactitude success register, otherwise hint correspond mistake information. In the development process, the usage Eclipse be used as development environment and added to carry to provide to the Struts and the Hibernate in the meantime better control and support of three square plug-in MyEclipse, Web server usage Tomcat, the database chose to use Mysql. Carry on an allocation to the Hibernate first, need to the system auto the born

hibernate.cfg. xml carry on modification, allocation good database conjunction of various parameter and definition the data reflect to shoot a document. Because the Hibernate take of conjunction pond main used for test, the function isn't very good, can pass JNDI will it modification is usage Tomcat of conjunction pond.

7、Summary

In this paper, we introduced the Struts application framework. And introduces some basic knowledge about Spring and Hibernate,. We also show how to use Hibernate and Struts development J2EE, and how it used to be servlets and JSP in combination in the same application. Now that you have a taste of the Strtus Web application, after that we will dig deeper into the theory and practice behind the Struts architectu

基于SSH的web技术介绍

1、引言

随着Java技术的逐渐成熟与完善,作为建立企业级应用的标准平台,J2EE 平台得到了长足的发展。借助于J2EE规范中包含的多项技术:Enterprise JavaBean(EJB)、Java Servlets(Servlet)、Java Server Pages(JSP)、Java Message Service(JMS)等,开发出了许多应用系统。但是,在传统J2EE应用的开发过程中也出现了一些问题:

1)数据模型和逻辑模型之间的矛盾。目前使用的数据库基本上都是关系型数据库,而Java本质上是一种面向对象的语言,对象在存储和读取时使用SQL和JDBC进行数据库操作,降低了编程的效率以及系统的可维护性。

2)传统的J2EE应用多采用基于EJB的重量级框架,这种框架适合于开发大型企业应用,但是使用EJB容器进行开发和调试需要耗费大量时间。为了降低代码的耦合性,提高系统的开发效率,本文提出了一种基于Struts框架、Spring框架和Hibernate框架的J2EE应用开发策略。

2、用Struts实现MVC架构

MVC(Model-View-Controller)由Trygve Reenskaug提出,首先被应用在SmallTalk-80环境中,是许多交互和界面系统的构成基础。根据界面设计可变性的需求,MVC把交互系统的组成分解成模型、视图、控制器三部分。模型(Model)是软件所处理问题逻辑在独立于外在显示内容和形式情况下的内在抽象,封装了

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问题的核心数据、逻辑和功能的计算关系,独立于具体的界面表达和I/O操作。视图(View)把表示模型数据及逻辑关系和状态的信息及特定形式展示给用户。它从模型获得显示信息,对于相同的信息可以有多个不同的显示形式或视图。控制器(Controller)是处理用户与软件的交互操作的,其职责是控制提供模型中任何变化的传播,确保用户界面于模型间的对应联系;它接受用户的输入,将输入反馈给模型,进而实现对模型的计算控制,是使模型和视图协调工作的部件。通常一个视图对应一个控制器。模型、视图与控制器的分离,使得一个模型可以具有多个显示视图。如果用户通过某个视图的控制器改变了模型的数据,所有其它依赖于这些数据的视图都应反映到这些变化。因此,无论何时发生了何种数据变化,控制器都会将变化通知所有的视图,导致显示的更新。这实际上是一种模型的变化-传播机制。

Struts框架最早是作为Apache Jakarta项目的组成部分问世运做,它继承了MVC 的各项特性,并根据J2EE的特点,做了相应的变化与扩展。Struts框架很好的结合了Jsp,Java Servlet,Java Bean,Taglib等技术。在Struts中,承担MVC中控制器角色的是ActionServlet。ActionServlet是一个通用的控制组件。这个控制组件提供了处理所有发送到Struts的HTTP请求的入口点。它截取和分发这些请求到相应的动作类(这些动作类都是Action类的子类)。另外控制组件也负责用相应的请求参数填充Action Form(FromBean),并传给动作类(ActionBean)。动作类访问核心商业逻辑,即访问Java Bean或调用EJB。最后动作类把控制权传给后续的JSP文件,由JSP文件生成视图。所有这些控制逻辑利用Struts-config.xml 文件来配置。在Struts框架中,视图主要由JSP生成页面完成,Struts提供丰富的JSP 标签库,这有利于分开表现逻辑和程序逻辑。模型以一个或多个Java Bean的形式

存在。在Struts中,主要存在三种Bean,分别是:Action,ActionForm,EJB或者Java Bean。Struts框架没有具体定义模型层的实现,在实际开发中,模型层通常是和业务逻辑紧密相连的,并且要对底层数据进行操作。下面介绍一种开发策略,将Hibernate引入到Struts框架的模型层中,使用它来进行数据封装和映射,提供持久化的支持。

3、Spring 应用构架

Spring明显区别于其他轻量级application framework,它将专注于web的支持,与struts和webwork有着明显的区别。在和struts和webwork的对比上,Spring是一个服务于所有层面的application framework:提供了bean的配置基础,AOP的支持,JDBC的提取框架,抽象事务支持,等等。它有一个非常显著的特点:在某个层面上如果你不需要Spring的支持,你就可以不使用String的class,只使用它的某一部分的功能。从它的设计理念,你可以看到String帮助你实现了真正的逻辑层和web层的分离:例如。一个校验应用将不用依靠controllers,就可以实现。这样的目标是更好的重用和易测:过分依靠不必要的容器和框架将不能实现这一点。

当然,Spring的自己的web支持和通常框架模式的细致完整.然而,Spring 替换struts,webwork或者其他的web方案非常的容易.对于Spring的web支持或者不同的地方,Spring 允许你在web容器里面建立一个中间层,在测试环境或者标准独立的应用里面来设置重用你的商务逻辑.还有在J2EE环境里面,你的商务逻辑不必依靠容器提供的服务,像JTA ,EJB的支持.良好的构架的web应用可以运行在任何容器上,如,Tomcat 或者Resin.值得注意的是,Spring不是和已经存在的解决方案进行竞争. 我们鼓励结合标准的技术,如,Servlet, JSP,

JTA, JNDI, JDBC, and JDO,和非常匹配的工具,如,Hibernate, Velocity, Log4J, and Caucho's Hessian/Burlap.这个框架的的设计思想是在你的应用需要改良的时候,你将会做一些技术的选择:例如,如果你需要分布式事务处理,你可能需要用Spring的Jta TransactionManager来实现JTA服务.或者,用DataSourceTransactionManager or HibernateTransactionManager 来实现美妙完美的单个数据库交换。

4、Spring web 框架的设计思想

Spring框架通过配置操作mappings,展示resolution,本地化和模版集成围绕着分派请求操作的servlet - DispatcherServlet设计的.缺省的操作是一个非常简单的控制接口, 他只提供了ModelAndView handleRequest(request,response)方法.这将用于一个应用的控制,但是,如果你想包含多个层次的控制,AbstractController, AbstractCommandController, MultiActionController, SimpleFormController, AbstractWizardFormController将帮助你完成.应用控制将代表那些子系统.注意,你可以选择一个适当的基类:如果你没有web form,你就不必用FormController.这就是和Struts最大的不同. 你可以通过命令或者form 对象来操作任何对象:这不需要接口工具或者一个基础类的驱动.Spring的数据邦定是非常的灵活的.举例来说,它描述了具有在应用范围内的校验错误的输入机制,但不是系统错误.所以在你的form对象里面你不必复制你的业务对象的string属性,只操作出错的子任务,或者适当地转换string.换句话说,它通常可以很好的直接邦定你的业务对象. 这也是和struts围绕请求基础类Action和ActionForm(每个action操作类型) 建立主要的不同之一. 对比WebWork,Sping 更多的区别在于对象角色:Sping支持控制器的感念,一个操作命令或者form对

象,和得到数据传递给视图的模式.这个模式通常包含命令和form对象,但有时也包含任意的参考数据.换句话说,一个WebWork Action联合所有这些角色到一个单独的对象.WebWork允许你用已经存在的业务对象作为你form的一部分,但是只生成各自Action 的bean属性. 最后,操作请求的Action实例在一个视图里面获得付值和form population. 然而,参考数据也需要作为Action的属性被模拟. 一个类里面有太多的角色是值得讨论的. 关于视图:Spring的视图方案非常的灵活. 一个控制器执行可以通过response返回ModelAndView对象null,就可以直接写到一个视图.在通常的状况下,一个ModelAndView实例结合了一个view 和一个model Map,包含了bean name和通讯对象(像命令或者form,参考数据等等). View名称是非常高端的的配置,不是通过bean name, 一个properties 文件就是通过你自己的ViewResolver.这个抽象的model Map允许你在视图层面完成提取,没有任何的争辩JSP/Velocity或者其他,每一种都可以直接完整使用.这个model Map 还可以简单得得到适当的格式化数据的转换,像JSP请求属性或者Velocity 模版模式.

5、Hibernate应用框架

数据持久层及Hibernate Hibernate是一个数据持久层框架,是一种实现对象和关系之间映射(O/R Mapping)的工具,它对JDBC进行了轻量级的对象封装,使程序员可以使用对象编程思想来操作数据库。它不仅提供了从Java类到数据表的映射,也提供了数据查询和恢复机制。相对于使用JDBC和SQL来操作数据库,使用Hibernate能大大的提高实现的效率。Hibernate框架用配置文件的形式来定义Java对象和数据表之间的映射关系,同时在更深的层面将数据表之间的关系解释为Java对象之间的继承及包含等关系。通过使用HQL语句将复杂的关系算法用对

象的方式描述,在很大程度上简化了对数据的查询,加快了开发的效率。在Hibernate中有一个简单而直观的API,用于对数据库所表示的对象执行查询。要创建或修改这些对象,只需在程序中与它们进行交互,然后告诉Hibernate保存即可。这样,大量封装持久化操作的业务逻辑不再需要编写烦琐的JDBC语句,从而使数据持久层得到了极大的简化。

6、运用Hibernate和Struts开发J2EE应用

以在J2EE应用中非常普遍的用户登录过程为例,来说明上述体系结构是如何具体运用的。登录的流程非常清晰:用户从登录页面login.jsp输入登录信息,系统对登录信息进行验证,如果正确则成功登录,否则提示相应错误信息。在开发过程中,使用Eclipse做为开发环境,同时加载了对Struts及Hibernate提供更好的控制和支持的第三方插件MyEclipse,Web服务器使用Tomcat,数据库选用了Mysql。首先对Hibernate进行配置,只需要对系统自动生成的hibernate.cfg.xml 进行修改,配置好数据库连接的各种参数以及定义数据映射文件。由于Hibernate 所带的连接池主要用于测试,性能不是很好,可以通过JNDI将其修改为使用Tomcat的连接池。

7、小结

在本文中,我们介绍了Struts应用框架。并介绍了一些基本知识,关于Spring,以及Hibernate。我们也说明了如何运用Hibernate和Struts开发J2EE,以及它如何用来将servlets和JSP 在结合在同一个应用之中。现在你已经有关于Strtus Web 应用程序模样的初步印象,以后我们将更深入的讨论Strtuts框架的理论和具体实践。

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供配电系统 摘要:电力系统的基本功能是向用户输送电能。lOkV配电网是连接供电电源与工业、商业及生活用电的枢纽,其网络庞大及复杂。对于所有用户都期望以最低的价格买到具有高度可靠性的电能。然而,经济性与可靠性这两个因素是互相矛盾的。要提高供电网络的可靠性就必须增加网络建设投资成本。但是,如果提高可靠性使用户停电损失的降低小于用于提高可靠性所增加的投资,那么这种建设投资就没有价值了。通过计算电网的投资和用户停电的损失,最终可找到一个平衡点,使投资和损失的综合经济性最优。 关键词:供配电,供电可靠性,无功补偿,负荷分配 1 引言 电力体制的改革引发了新一轮大规模的电力建设热潮从而极大地推动了电力技术革命新技术新设备的开发与应用日新月异特别是信息技术与电力技术的结合在很大程度上提高了电能质量和电力供应的可靠性由于技术的发展又降低了电力建设的成本进而推动了电网设备的更新换代本文就是以此为契机以国内外配电自动化中一些前沿问题为内容以配电自动化建设为背景对当前电力系统的热点技术进行一些较深入的探讨和研究主要完成了如下工作. (1)提出了配电自动化建设的两个典型模式即―体化模式和分立化模式侧重分析了分立模式下的配电自动化系统体系结构给出了软硬件配置主站选择管理模式最佳通讯方式等是本文研究的前提和实现平台. (2)针对配电自动化中故障测量定位与隔离以及供电恢复这一关键问题分析了线路故障中电压电流等电量的变化导出了相间短路工况下故障定位的数学描述方程并给出了方程的解以及故障情况下几个重要参数s U& s I& e I& 选择表通过对故障的自动诊断与分析得出了优化的隔离和恢复供电方案自动实现故障快速隔离与网络重构减少了用户停电范围和时间有效提高配网供电可靠性文中还给出了故障分段判断以及网络快速重构的软件流程和使用方法. (3)状态估计是实现配电自动化中关键技术之一本文在阐述状态估计方法基础上给出了不良测量数据的识别和结构性错误的识别方法针对状态估计中数据对基于残差的坏数据检测和异常以及状态量中坏数据对状态估计的影响及存在的问题提出了状态估计中拓扑错误的一种实用化检测和辩识方法针对窃电漏计电费问题独创性提出一种通过电量突变和异常分析防止窃电的新方法并在潍坊城区配电得到验证. (4)针对配电网负荷预测建模困难参数离散度大以及相关因素多等问题本文在分析常规负荷预测模型及方法基础上引入了气象因素日期类型社会环境影响等参数给出了基于神经网络的电力负荷预测方法实例验证了方法的正确性.

外文翻译- 液压系统概述

附录: 外文资料与中文翻译 外文资料: Hydraulic System Hydraulic presser drive and air pressure drive hydraulic fluid as the transmission is made according to the 17th century, Pascal's principle of hydrostatic pressure to drive the development of an emerging technology, the United Kingdom in 1795 ? Braman Joseph (Joseph Braman ,1749-1814), in London water as a medium to form hydraulic press used in industry, the birth of the world's first hydraulic press. Media work in 1905 will be replaced by oil-water and further improved. After the World War I (1914-1918) ,because of the extensive application of hydraulic transmission, espec- ially after 1920, more rapid development. Hydraulic components in the late 19th century about the early 20th century, 20 years, only started to enter the formal phase of industrial production. 1925 Vickers (F. Vikers) the invention of the pressure balanced vane pump, hydraulic components for the modern industrial or hydraulic transmission of the gradual establishment of the foundation. The early 20th century G ? Constantimscofluct- uations of the energy carried out by passing theoretical and practical research; in 1910 on the hydraulic trans- mission (hydraulic coupling, hydraulic torque converter, etc.) contributions, so that these two areas of develo- pment. The Second World War (1941-1945) period, in the United States 30% of machine tool applications in the hydraulic transmission. It should be noted that the development of hydraulic transmission in Japan than Europe

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毕业设计(论文)外文资料翻译 学院:电气信息学院 专业:电气工程及其自动化 姓名:郭骥翔 学号: 081001227 外文出处: Adaptive torque control of variable speed wind turbines 附件: 1.外文资料翻译译文;2.外文原文。 指导教师评语: 签名: 年月日(用外文写)

附件1:外文资料翻译译文 多种风力涡轮机的适应性转矩控制 4.5 使用SymDyn进行仿真 所有先前所描述的模拟是使用SimInt来演示的,其中,如前所述,包括唯一的转子角速度自由度,与复杂的仿真工具比,如SymDyn和FAST,他能够更快的运行。然而,为了确认目的,与其他更流行的仿真工具比较SimInt在适应运行上的增益是很有价值的。适应性的增加并不是期望它能够同等的适应每一个仿真工具,因为每个仿真工具都有其独到的涡轮机模型。但是如果每个涡轮机的造型都相同,如同本例,那么在SimInt 和SymDyn中则有着基本相似的适应性增益(CART)。在数据4-10中,这种相似性被明显的显示出来。 SimInt和SymDyn仿真工具都是由零时刻开始,而且大多数参数初值都相同,如M,角速度等。然而,尽管这两个涡轮机模型都设立了最佳转矩控制M*,但是CP表面却有着不同程度的峰值。因此为了使初始过程大致相同,初始Pfavg值应有相同的最大比例,而不是相同的绝对值。在显示标准化M值4-10的上图中,显示了合理的类似数据。但在30到60小时后,仿真工具的适应性增益开始出现分歧。但在此之后,他们再次互相接近,在从模拟开始100小时到模拟结束这段时间,他们保持基本重合。从下图中也可以清楚的观察出,每个仿真工具都在调整他们的增益M,并采集最大输出功率。 尽管SimInt仿真速度差不多是SymDyn仿真速度的五倍,在图4-10中所显示的SymDyn 数据是唯一一个可以验证适应性增益法则的模拟工具。在这个展示了两个模拟工具合理

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附录 Hydraulic System Hydraulic presser drive and air pressure drive hydraulic fluid as the transmission is made according to the 17th century, Pascal's principle of hydrostatic pressure to drive the development of an emerging technology, the United Kingdom in 1795 ?Barman Joseph (Joseph Barman, 1749-1814), in London water as a medium to form hydraulic press used in industry, the birth of the world's first hydraulic press. Media work in 1905 will be replaced by oil-water and further improved. After the World War I (1914-1918) ,because of the extensive application of hydraulic transmission, especially after 1920, more rapid development. Hydraulic components in the late 19th century about the early 20th century, 20 years, only started to enter the formal phase of industrial production. 1925 Vickers (F. Vickers) the invention of the pressure balanced vane pump, hydraulic components for the modern industrial or hydraulic transmission of the gradual establishment of the foundation. The early 20th century G ? Constantia scofluctuations of the energy carried out by passing theoretical and practical research; in 1910 on the hydraulic trans- mission (hydraulic coupling, hydraulic torque converter, etc.) contributions, so that these two areas of development. The Second World War (1941-1945) period, in the United States 30% of machine tool applications in the hydraulic transmission. It should be noted that the development of hydraulic transmission in Japan than Europe and the United States and other countries for

电力系统负荷预测及方法外文翻译.doc

电力系统负荷预测及方法(外文翻译)

Power system load forecasting methods and characteristics of Abstract: The load forecasting in power system planning and operation play an important role, with obvious economic benefits, in essence, the electricity load forecasting market demand forecast. In this paper, a systematic description and analysis of a variety of load forecasting methods and characteristics and that good load forecasting for power system has become an important means of modern management. Keywords: power system load forecasting electricity market construction Planning 1.Introduction Load forecasting demand for electricity from a known starting to consider the political, economic, climate and other related factors, the future demand for electricity to make predictions. Load forecast includes two aspects: on the future demand (power) projections and future electricity consumption (energy) forecast.

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Electric Power System Electrical power system refers to remove power and electric parts of the part,It includes substation, power station and distribution. The role of the power grid is connected power plants and users and with the minimum transmission and distribution network disturbance through transport power, with the highest efficiency and possibility will voltage and frequency of the power transmission to the user fixed .Grid can be divided into several levels based on the operating voltage transmission system, substructure, transmission system and distribution system, the highest level of voltage transmission system is ZhuWangJia or considered the high power grids. From the two aspects of function and operation, power can be roughly divided into two parts, the transmission system and substation. The farthest from the maximum output power and the power of the highest voltage grade usually through line to load. Secondary transmission usually refers to the transmission and distribution system is that part of the middle. If a plant is located in or near the load, it might have no power. It will be direct access to secondary transmission and distribution system. Secondary transmission system voltage grade transmission and distribution system between voltage level. Some systems only single second transmission voltage, but usually more than one. Distribution system is part of the power system and its retail service to users, commercial users and residents of some small industrial users. It is to maintain and in the correct voltage power to users responsible. In most of the system, Distribution system accounts for 35% of the total investment system President to 45%, and total loss of system of the half . More than 220kv voltage are usually referred to as Ultra high pressure, over 800kv called high pressure, ultra high voltage and high pressure have important advantages, For example, each route high capacity, reduce the power needed for the number of transmission. In as high voltage to transmission in order to save a conductor material seem desirable, however, must be aware that high voltage transmission can lead to transformer, switch equipment and other instruments of spending increases, so, for the voltage transmission to have certain restriction, allows it to specific circumstances in economic use. Although at present, power transmission most is through the exchange of HVDC transmission, and the growing interest in, mercury arc rectifier and brake flow pipe into the ac power generation and distribution that change for the high voltage dc transmission possible.

液压系统外文翻译

Hydraulic System Hydraulic presser drive and air pressure drive hydraulic fluid as the transmission is made according to the 17th century, Pascal's principle of hydrostatic pressure to drive the development of an emerging technology, the United Kingdom in 1795 ?Braman Joseph (Joseph Braman ,1749-1814), in London water as a medium to form hydraulic press used in industry, the birth of the world's first hydraulic press. Media work in 1905 will be replaced by oil-water and further improved. After the World War I (1914-1918) ,because of the extensive application of hydraulic transmission, espec- ially after 1920, more rapid development. Hydraulic components in the late 19th century about the early 20th century, 20 years, only started to enter the formal phase of industrial production. 1925 Vickers (F. Vikers) the invention of the pressure balanced vane pump, hydraulic components for the modern industrial or hydraulic transmission of the gradual establishment of the foundation. The early 20th century G ? Constan timscofluct- uations of the energy carried out by passing theoretical and practical research; in 1910 on the hydraulic trans- mission (hydraulic coupling, hydraulic torque converter, etc.) contributions, so that these two areas of develo- pment. The Second World War (1941-1945) period, in the United States 30% of machine tool applications in the hydraulic transmission. It should be noted that the development of hydraulic transmission in Japan than Europe and the United States and other countries for nearly 20 years later. Before and after in 1955, the rapid development of Japan's hydraulic drive, set up in 1956, "Hydraulic Industry." Nearly 20 to 30 years, the development of Japan's fast hydraulic transmission, a world leader. Hydraulic transmission There are many outstanding advantages, it is widely used, such as general industr- ial use of plastics processing machinery, the pressure of machinery, machine tools, etc.; operating machinery engineering machinery, construction machinery, agricultural machinery, automobiles, etc.; iron and steel indu- stry metallurgical machinery, lifting equipment, such as roller adjustment device; civil water projects with flo- od control and dam gate devices, bed lifts installations, bridges and other manipulation of institutions; speed turbine power

电力系统外文翻译

外文资料翻译 Electric Power System Introduction Electric Power System,components that transform other types of energy into electrical energy and transmit this energy to a consumer.The production and transmission of electricity is relatively efficient and inexpensive,although unlike other forms of energy,electricity is not easily stored and thus must generally be used as it is being produced. Components of an Electric Power System A modern electric power system consists of six main components:(1)the power station,(2)a set of transforms to raise the generated power to the high voltages used on the transmission lines,(3)the transmission,(4)the substations at which the power is stepped down to the voltage on the distribution lines,(5)the distribution lines,and(6)the transformers that lower the distribution voltage to the level used by the consumer's equipment. Power Station The power station of a power system consists of a prime mover,such as a turbine driven by water,steam,or combustion gases that operate a system of electric motors and generators.Most of the world's electric power is generated in steam plants driven by coal,oil,nuclear energyor gas.A smaller percentage of the world's electric power is generated by hydroelectric(waterpower),diesel,and internal-combustion plants. Transformers Modern electric power systems use transformers to convert electricity into different voltages.With transformers,each stage of the system can be operated at an appropriate voltage.In a typical system,the generators at the power station deliver a voltage of from 1,000 to 26,000 volts(V).Transformers step this voltage up to values ranging from 138,000 to 765,000 V for the long-distances.At the substation the voltage may be transformed down to levels of 69,000 to 138,000 V for further transfer on the distribution system.Another set of transformers step the voltage down again to a distribution level such as 2,400or 4,160 V or 15,27,or 33 kilovolts(KV).Finally the voltage is transformed once again at the distribution transformer near the point of use to 240 or 120 V. Transmission Lines The lines of high-voltage transmission systems are usually composed of wires of copper,aluminum,or copper-clad or aluminum-clad steel,which are suspend from tall latticework towers of steel by strings of porcelain insulators.By the use of clad steel wires and high towers,the distance between towers can be increased,and the cost of the transmission line thus reduced.In modern installations

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