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毕业设计(论文)外文翻译

毕业设计(论文)外文翻译
毕业设计(论文)外文翻译

外文原文

The technique development history of JSP

Brian Wright Michael Freedman

https://www.doczj.com/doc/7f10263506.html,/pdf/introduction-to-machine-learning/ The Java Server Pages( JSP) is a kind of according to web of the script plait distance technique, similar carries the script language of Java in the server of the Netscape company of server- side JavaScript( SSJS) and the Active Server Pages( ASP) of the Microsoft. JSP compares the SSJS and ASP to have better can expand sex, and it is no more exclusive than any factory or some one particular server of Web. Though the norm of JSP is to be draw up by the Sun company of, any factory can carry out the JSP on own system.

The After Sun release the JSP( the Java Server Pages) formally, the this kind of new Web application development technique very quickly caused the people's concern. JSP provided a special development environment for the Web application that establishes the high dynamic state. According to the Sun parlance, the JSP can adapt to include the Apache WebServer, IIS4.0 on the market at inside of 85% server product.

This chapter will introduce the related knowledge of JSP and Databases, and JavaBean related contents, is all certainly rougher introduction among them basic contents, say perhaps to is a Guide only, if the reader needs the more detailed information, pleasing the book of consult the homologous JSP.

A. Generalize

The JSP(Java Server Pages) is from the company of Sun Microsystems initiate, the many companies the participate to the build up the together of the a kind the of dynamic the state web the page technique standard, the it have the it in the construction the of the dynamic state the web page the strong but the do not the especially of the function. JSP and the technique of ASP of the Microsoft is very alike. Both all provide the ability that mixes with a certain procedure code and is explain by the language engine to carry out the procedure code in the code of HTML. Underneath we are simple of carry on the introduction to it.

JSP pages are translated into servlets. So, fundamentally, any task JSP pages can perform could also be accomplished by servlets. However, this underlying

equivalence does not mean that servlets and JSP pages are equally appropriate in all scenarios. The issue is not the power of the technology, it is the convenience, productivity, and maintainability of one or the other. After all, anything you can do on a particular computer platform in the Java programming language you could also do in assembly language. But it still matters which you choose.

JSP provides the following benefits over servlets alone:

? It is easier to write and maintain the HTML. Your static code is ordinary HTML: no extra backslashes, no double quotes, and no lurking Java syntax.

? You can use standard Web-site development tools. Even HTML tools that know nothing about JSP can be used because they simply ignore the JSP tags.

? You can divide up your development team. The Java programmers can work on the dynamic code. The Web developers can concentrate on the presentation layer. On large projects, this division is very important. Depending on the size of your team and the complexity of your project, you can enforce a weaker or stronger separation between the static HTML and the dynamic content.

Now, this discussion is not to say that you should stop using servlets and use only JSP instead. By no means. Almost all projects will use both. For some requests in your project, you will use servlets. For others, you will use JSP. For still others, you will combine them with the MVC architecture . You want the appropriate tool for the job, and servlets, by themselves, do not complete your toolkit.

B. Source of JSP

The technique of JSP of the company of Sun, making the page of Web develop the personnel can use the HTML perhaps marking of XML to design to turn the end page with format. Use the perhaps small script future life of marking of JSP becomes the dynamic state on the page contents.( the contents changes according to the claim of)

The Java Servlet is a technical foundation of JSP, and the large Web applies the development of the procedure to need the Java Servlet to match with with the JSP and then can complete, this name of Servlet comes from the Applet, the local translation method of now is a lot of, this book in order not to misconstruction, decide the direct adoption Servlet but don't do any translation, if reader would like to, can call it as" small service procedure". The Servlet is similar to traditional CGI, ISAPI, NSAPI etc. Web procedure development the function of the tool in fact, at use the Java Servlet hereafter, the customer need not use again the lowly method of CGI of efficiency, also

need not use only the ability come to born page of Web of dynamic state in the method of API that a certain fixed Web server terrace circulate. Many servers of Web all support the Servlet, even not support the Servlet server of Web directly and can also pass the additional applied server and the mold pieces to support the Servlet. Receive benefit in the characteristic of the Java cross-platform, the Servlet is also a terrace irrelevant, actually, as long as match the norm of Java Servlet, the Servlet is complete to have nothing to do with terrace and is to have nothing to do with server of Web. Because the Java Servlet is internal to provide the service by the line distance, need not start a progress to the each claimses, and make use of the multi-threading mechanism can at the same time for several claim service, therefore the efficiency of Java Servlet is very high.

But the Java Servlet also is not to has no weakness, similar to traditional CGI, ISAPI, the NSAPI method, the Java Servlet is to make use of to output the HTML language sentence to carry out the dynamic state web page of, if develop the whole website with the Java Servlet, the integration process of the dynamic state part and the static state page is an evil-foreboding dream simply. For solving this kind of weakness of the Java Servlet, the SUN released the JSP.

A number of years ago, Marty was invited to attend a small 20-person industry roundtable discussion on software technology. Sitting in the seat next to Marty was James Gosling, inventor of the Java programming language. Sitting several seats away was a high-level manager from a very large software company in Redmond, Washington. During the discussion, the moderator brought up the subject of Jini, which at that time was a new Java technology. The moderator asked the manager what he thought of it, and the manager responded that it was too early to tell, but that it seemed to be an excellent idea. He went on to say that they would keep an eye on it, and if it seemed to be catching on, they would follow his company's usual "embrace and extend" strategy. At this point, Gosling lightheartedly interjected "You mean disgrace and distend."

Now, the grievance that Gosling was airing was that he felt that this company would take technology from other companies and suborn it for their own purposes. But guess what? The shoe is on the other foot here. The Java community did not invent the idea of designing pages as a mixture of static HTML and dynamic code marked with special tags. For example, Cold Fusion did it years earlier. Even ASP (a product from the very software company of the aforementioned manager) popularized

this approach before JSP came along and decided to jump on the bandwagon. In fact, JSP not only adopted the general idea, it even used many of the same special tags as ASP did.

The JSP is an establishment at the model of Java servlets on o f the expression layer technique, it makes the plait write the HTML to become more simple.Be like the SSJS, it also allows you carry the static state HTML contents and servers the script mix to put together the born dynamic state exportation. JSP the script language that the Java is the tacit approval, however, be like the ASP and can use other languages( such as JavaScript and VBScript), the norm of JSP also allows to use other languages.

C. JSP characteristics

Is a service according to the script language in some one language of the statures system this kind of discuss, the JSP should be see make is a kind of script language. However, be a kind of script language, the JSP seemed to be too strong again, almost can use all Javas in the JSP.

Be a kind of according to text originally of, take manifestation as the central development technique, the JSP provided all advantages of the Java Servlet, and, when combine with a JavaBeans together, providing a kind of make contents and manifestation that simple way that logic separate. Separate the contents and advantage of logical manifestations is, the personnel who renews the page external appearance need not know the code of Java, and renew the JavaBeans personnel also need not be design the web page of expert in hand, can use to take the page of JavaBeans JSP to define the template of Web, to build up a from have the alike external appearance of the website that page constitute. JavaBeans completes the data to provide, having no code of Java in the template thus, this means that these templates can be written the personnel by a HTML plait to support. Certainly, can also make use of the Java Servlet to control the logic of the website, adjust through the Java Servlet to use the way of the document of JSP to separate website of logic and contents.

Generally speaking, in actual engine of JSP, the page of JSP is the edit and translate type while carry out, not explain the type of .Explain the dynamic state web page development tool of the type, such as ASP, PHP3 etc., because speed etc. reason, have already can't satisfy current the large electronic commerce needs appliedly, traditional development techniques are all at to edit and translate the executive way change, such as the ASP → ASP+;PHP3 → PHP4.

In the JSP norm book, did not request the procedure in the JSP code part( be called the Scriptlet) and must write with the Java definitely. Actually, have some engines of JSP are adoptive other script languages such as the EMAC- Script, etc., but actually this a few script languages also are to set up on the Java, edit and translate for the Servlet to carry out of. Write according to the norm of JSP, have no Scriptlet of relation with Java also is can of, however, mainly lie in the ability and JavaBeans, the Enterprise JavaBeanses because of the JSP strong function to work together, so even is the Scriptlet part not to use the Java, edit and translate of performance code also should is related with Java.

D. JSP mechanism

To comprehend the JSP how unite the technical advantage that above various speak of, come to carry out various result easily, the customer must understand the differentiation of" the module develops for the web page of the center" and" the page develops for the web page of the center" first.

The SSJS and ASP are all in several year ago to release, the network of that time is still very young, no one knows to still have in addition to making all business, datas and the expression logic enter the original web page entirely heap what better solve the method. This kind of model that take page as the center studies and gets the very fast development easily. However, along with change of time, the people know that this kind of method is unwell in set up large, the Web that can upgrade applies the procedure. The expression logic write in the script environment was lock in the page, only passing to shear to slice and glue to stick then can drive heavy use. Express the logic to usually mix together with business and the data logics, when this makes be the procedure member to try to change an external appearance that applies the procedure but do not want to break with its llied business logic, apply the procedure of maintenance be like to walk the similar difficulty on the eggshell. In fact in the business enterprise, heavy use the application of the module already through very mature, no one would like to rewrite those logics for their applied procedure.HTML and sketch the designer handed over to the implement work of their design the Web plait the one who write, make they have to double work- Usually is the handicraft plait to write, because have no fit tool and can carry the script and the HTML contents knot to the server to put together. Chien but speech, apply the complexity of the procedure along with the Web to promote continuously, the development method that take page as the center limits sex to become to get up obviously.

At the same time, the people always at look for the better method of build up the Web application procedure, the module spreads in customer's machine/ server the realm. JavaBeans and ActiveX were published the company to expand to apply the procedure developer for Java and Windows to use to come to develop the complicated procedure quickly by" the fast application procedure development"( RAD) tool. These techniques make the expert in the some realm be able to write the module for the perpendicular application plait in the skill area, but the developer can go fetch the usage directly but need not control the expertise of this realm.

Be a kind of take module as the central development terrace, the JSP appeared. It with the JavaBeans and Enterprise JavaBeans( EJB) module includes the model of the business and the data logic for foundation, provide a great deal of label and a script terraces to use to come to show in the HTML page from the contents of JavaBeans creation or send a present in return. Because of the property that regards the module as the center of the JSP, it can drive Java and not the developer of Java uses equally. Not the developer of Java can pass the JSP label( Tags) to use the JavaBeans that the deluxe developer of Java establish. The developer of Java not only can establish and use the JavaBeans, but also can use the language of Java to come to control more accurately in the JSP page according to the expression logic of the first floor JavaBeans.

See now how JSP is handle claim of HTTP. In basic claim model, a claim directly was send to JSP page in. The code of JSP controls to carry on hour of the logic processing and module of JavaBeanses' hand over with each other, and the manifestation result in dynamic state bornly, mixing with the HTML page of the static state HTML code. The Beans can be JavaBeans or module of EJBs. Moreover, the more complicated claim model can see make from is request other JSP pages of the page call sign or Java Servlets.

The engine of JSP wants to chase the code of Java that the label of JSP, code of Java in the JSP page even all converts into the big piece together with the static state HTML contents actually. These codes piece was organized the Java Servlet that customer can not see to go to by the engine of JSP, then the Servlet edits and translate them automatically byte code of Java.

Thus, the visitant that is the website requests a JSP page, under the condition of it is not knowing, an already born, the Servlet actual full general that prepared to edit and

translate completes all works, very concealment but again and efficiently. The Servlet is to edit and translate of, so the code of JSP in the web page does not need when the every time requests that page is explain. The engine of JSP need to be edit and translate after Servlet the code end is modify only once, then this Servlet that editted and translate can be carry out. The in view of the fact JSP engine auto is born to edit and translate the Servlet also, need not procedure member begins to edit and translate the code, so the JSP can bring vivid sex that function and fast developments need that you are efficiently.

Compared with the traditional CGI, the JSP has the equal advantage. First, on the speed, the traditional procedure of CGI needs to use the standard importation of the system to output the equipments to carry out the dynamic state web page born, but the JSP is direct is mutually the connection with server. And say for the CGI, each interview needs to add to add a progress to handle, the progress build up and destroy by burning constantly and will be a not small burden for calculator of be the server of Web. The next in order, the JSP is specialized to develop but design for the Web of, its purpose is for building up according to the Web applied procedure, included the norm and the tool of a the whole set. Use the technique of JSP can combine a lot of JSP pages to become a Web application procedure very expediently.

外文翻译

JSP技术发展史

Brian Wright Michael Freedman

https://www.doczj.com/doc/7f10263506.html,/pdf/introduction-to-machine-learning/ Java Server Pages(JSP)是一种基于web的脚本编程技术,类似于网景公司的服务器端Java脚本语言——server-side JavaScript(SSJS)和微软的Active Server Pages(ASP)。JSP比SSJS和ASP具有更好的可扩展性,并且它不专属于任何一家厂商或某一特定的Web服务器。尽管JSP规范是由Sun公司制定的,但任何厂商都可以在自己的系统上实现JSP。

在Sun正式发布JSP(Java Server Pages)之后,这种新的Web应用开发技术很快引起了人们的关注。JSP为创建高度动态的Web应用提供了一个独特的开发环境。按照Sun的说法,JSP能够适应市场上包括Apache WebServer、IIS4.0在内的85%的服务器产品。

本文将介绍JSP相关的知识,以及JavaBean的相关内容,当然都是比较粗略的介绍其中的基本内容,或者说仅仅是一个Guide,如果读者需要更详细的信息,请参考相应的JSP的书籍。

A. 概述

JSP(Java Server Pages)是由Sun Microsystems公司倡导、许多公司参与一起建立的一种动态网页技术标准,其在动态网页的建设中有其强大而特别的功能。JSP与Microsoft的ASP技术非常相似。两者都提供在HTML代码中混合某种程序代码、由语言引擎解释执行程序代码的能力。下面我们简单的对它进行介绍。

JSP页面最终会转换成servler。因而,从根本上,JSP页面能够执行的任何任务都可以用servler来完成。然而,这种底层的等同性并不意味着servler 和JSP页面对于所有的情况都等同适用。问题不在于技术的能力,而是二者在便利性、生产率和可维护性上的不同。毕竟,在特定平台上能够用Java编程语言完成的事情,同样可以用汇编语言来完成,但是选择哪种语言依旧十分重要。和单独使用servler相比,JSP提供下述好处:

JSP中HTML的编写与维护更为简单。JSP中可以使用常规的HTML:没有额外的反斜杠,没有额外的双引号,也没有暗含的Java语法。

能够使用标准的网站开发工具。即使对那些对JSP一无所知的HTML工具,我们也可以使用,因为它们会忽略JSP标签(JSP tags)。

可以对开发团队进行划分。Java程序员可以致力于动态代码。Web开发人员可以将经理集中在表示层(presentation layer)上。对于大型的项目,这种划分极为重要。依据开发团队的大小,及项目的复杂程度,可以对静态HTML和动态内容进行弱分离(weaker separation)和强分离(stronger separation)。

在此,这个讨论并不是让您停止使用servlets,只使用JSP。几乎所有的项目都会同时用到这两种技术。针对项目中的某些请求,您可能会在MVC构架下组合使用这两项技术。我们总是希望用适当的工具完成相对应的工作,仅仅是servlet并不能填满您的工具箱。

B. JSP的由来

Sun公司的JSP技术,使Web页面开发人员可以使用HTML或者XML标识来设计和格式化最终页面。使用JSP标识或者小脚本来生成页面上的动态内容(内容是根据请求来变化的)。

Java Servlet是JSP技术的基础,而且大型的Web应用程序的开发需要Java Servlet和JSP配合才能完成,Servlet这个名称源于Applet,现在国内的翻译方式很多,本书为了避免误会,决定直接采用Servlet而不做任何翻译,读者如果愿意,可以称之为“小服务程序”。Servlet其实和传统的CGI、ISAPI、NSAPI 等Web程序开发工具的作用是相同的,在使用Java Servlet以后,用户不必再使用效率低下的CGI方式,也不必使用只能在某个固定Web服务器平台运行的API方式来动态生成Web页面。许多Web服务器都支持Servlet,即使不直接支持Servlet的Web服务器也可以通过附加的应用服务器和模块来支持Servlet。得益于Java的跨平台的特性,Servlet也是平台无关的,实际上,只要符合Java Servlet规范,Servlet是完全与平台无关且是与Web服务器无关的。由于Java Servlet内部是以线程方式提供服务,不必对于每个请求都启动一个进程,并且利用多线程机制可以同时为多个请求服务,因此Java Servlet效率非常高。

但Java Servlet也不是没有缺点,和传统的CGI、ISAPI、NSAPI方式相同,Java Servlet是利用输出HTML语句来实现动态网页的,如果用Java Servlet 来开发整个网站,动态部分和静态页面的整合过程简直就是一场恶梦。为了解决Java Servlet的这种缺点,SUN推出了JSP。

许多年前,Marty受到邀请,参加一个有关软件技术的小型(20个人)研讨会.做在Marty旁边的人是James Gosling--- Java编程语言的发明者。隔几个位置,是来自华盛顿一家大型软件公司的高级经理。在讨论过程中,研讨会的主席提出了Jini的议题,这在当时是一项新的Java技术.主席向该经理询问他的想法.他继续说,他们会持续关注这项技术,如果这项技术变得流行起来,他们会遵循公司

的“接受并扩充(embrace and extend)”的策略.此时, Gosling随意地插话说“你的意思其实就是不接受且不扩充(disgrace and distend)。”

在此, Gosling的抱怨显示出,他感到这个公司会从其他公司那里拿走技术,用于他们自己的目的.但你猜这次怎么样?这次鞋子穿在了另一只脚上。Java社团没有发明这一思想----将页面设计成由静态HTML和用特殊标签标记的动态代码混合组成.。ColdFusion多年前就已经这样做了。甚至ASP(来自于前述经理所在公司的一项产品)都在JSP出现之前推广了这种方式。实际上,JSP不只采用了这种通用概念,它甚至使用许多和ASP相同的特殊标签。

JSP是建立在Java servlets模型之上的表达层技术,它使编写HTML变得更简单。像SSJS一样,它也允许你将静态HTML内容与服务器端脚本混合起来生成动态输出。JSP把Java作为默认的脚本语言,然而,就像ASP可以使用其他语言(如JavaScript和VBScript)一样,JSP规范也允许使用其他语言。

C. JSP的特点

按照脚本语言是服务于某一个子系统的语言这种论述,JSP应当被看作是一种脚本语言。然而,作为一种脚本语言,JSP又显得过于强大了,在JSP中几乎可以使用全部的Java类。

作为一种基于文本的、以显示为中心的开发技术,JSP提供了Java Servlet 的所有好处,并且,当与一个JavaBeans类结合在一起时,提供了一种使内容和显示逻辑分开的简单方式。分开内容和显示逻辑的好处是,更新页面外观的人员不必懂得Java代码,而更新JavaBeans类的人员也不必是设计网页的行家里手,就可以用带JavaBeans类的JSP页面来定义Web模板,以建立一个由具有相似的外观的页面组成的网站。JavaBeans类完成数据提供,这样在模板中就没有Java 代码,这意味着这些模板可以由一个HTML编写人员来维护。当然,也可以利用Java Servlet来控制网站的逻辑,通过Java Servlet调用JSP文件的方式来将网站的逻辑和内容分离。

一般来说,在实际的JSP引擎中,JSP页面在执行时是编译式,而不是解释式的。解释式的动态网页开发工具如ASP、PHP3等由于速度等原因已经满足不了当前大型电子商务应用的需要了,传统的开发技术都在向编译执行的方式改变,如ASP→ASP+;PHP3→PHP4。

在JSP规范书中,并没有明确要求JSP中的程序代码部分(称为Scriptlet)一定要用Java来写。实际上,有一些JSP引擎就是采用的其他脚本语言,如EMAC-Script、WebL等,但实际上这几种脚本语言也是构建在Java上面,编译为Servlet来实现的。按照JSP规范书写,和Java没有任何关系的Scriptlet 也是可以的,不过,由于JSP的强大功能主要在于能和JavaBeans、Enterprise

JavaBeans一起工作,所以即使是Scriptlet部分不使用Java,编译成的执行代码也应该是与Java相关的。

D. JSP的机制

要理解JSP怎样联合以上各种所提到的技术的优点,来轻而易举地实现各种效果,用户必须首先了解“组件为中心的网页开发”和“页面为中心的网页开发”的区别。

SSJS和ASP都是在几年前推出的,那时网络还很年轻,没有人知道除了把所有的商务、数据和表达逻辑统统堆进原始网页中之外还有什么更好的解决方法。这种以页面为中心的模型容易学习并且得到相当快速的发展。然而,随着时间的推移,人们认识到这种方法不适于构建大型的、可升级的Web应用程序。在脚本环境中书写的表达逻辑被锁在页面内,只有通过剪切和粘贴才能被重用。表达逻辑通常和商务及数据逻辑混在一起,这使得当程序员试图改变一个应用程序的外观而不想破坏与之紧密结合的商务逻辑时,应用程序的维护就像在蛋壳上走路一样困难。其实在企业中,可重用组件的应用早已经很成熟,没有人愿意为它们的应用程序重写那些逻辑。HTML和图形设计师把它们的设计的实施工作交给了Web编写者,使他们不得不加倍工作——常常是手工编写,因为没有合适的工具可以把服务器端脚本与HTML内容结合起来。简而言之,随着Web应用程序的复杂性不断提升,以页面为中心的开发方式的局限性变得明显起来。

与此同时,人们一直在寻找建立Web应用程序的更好方法,组件在客户机/服务器领域流行起来。JavaBeans和ActiveX被“快速应用程序开发”(RAD)工具发行商推广给Java和Windows应用程序开发者用来快速开发复杂的程序。这些技术使某领域内的专家可以为本领域内的垂直应用编写组件,而开发者可以直接拿来使用而不必掌握这一领域的专门技术。

作为一种以组件为中心的开发平台,JSP出现了。它以JavaBeans和Enterprise JavaBeans(EJB)组件包含商务和数据逻辑的模型为基础,提供大量标签和一个脚本平台用来在HTML页中显示由JavaBeans产生或回送的内容。由于JSP的以组件为中心的性质,它可以被Java和非Java开发者同样使用。非Java开发者可以通过JSP的标签(Tags)来使用高级Java开发者创建的JavaBeans。Java开发者不仅可以创建和使用JavaBeans,还能在JSP页中使用Java语言来更精密地控制基于底层JavaBeans的表达逻辑。

现在来看看JSP是如何处理HTTP请求的。在基本请求模型中,一个请求直接被送到JSP页中。JSP代码控制着进行逻辑处理时与JavaBeans组件的交互,并在动态生成的、混合了静态HTML代码的HTML页中显示结果。Beans 可以是JavaBeans 或EJB组件。另外,更加复杂的请求模型可看作从被请求页呼叫其他

JSP页或Java Servlets。

JSP引擎实际上要把JSP标签、JSP页中的Java代码甚至连同静态HTML内容都转换为大块的Java代码。这些代码块被JSP引擎组织到用户看不到的Java Servlet中去,然后Servlet自动把它们编译成Java字节码。这样,当网站的访问者请求一个JSP页时,在它不知道的情况下,一个已经生成的、预编译过的Servlet实际上将完成所有的工作,非常隐蔽而又高效。因为Servlet是编译过的,所以网页中的JSP代码不需要在每次请求该页时被解释一遍。JSP引擎只需在Servlet代码最后被修改后编译一次,然后这个编译过的Servlet就可以被执行了。由于是JSP引擎自动生成并编译Servlet,不用程序员动手编译代码,所以JSP能带给你高效的性能和快速开发所需的灵活性。

和传统的CGI相比较,JSP有相当的优势。首先,在速度上,传统的CGI程序需要使用系统的标准输入输出设备来实现动态网页的生成,而JSP是直接和服务器相关联的。而且对于CGI来说,每一个访问就需要新增加一个进程来处理,进程不断地建立和销毁对于作为Web服务器的计算机将是不小的负担。其次,JSP 是专门为Web开发而设计的,其目的是为了建立基于Web的应用程序,包含了一整套的规范和工具。使用JSP技术可以很方便地将一大堆JSP页面组合成为一个Web应用程序。

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毕业论文外文翻译模版

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1 外文翻译的基本内容 应选择与本课题密切相关的外文文献(学术期刊网上的),译成中文,与原文装订在一起并独立成册。在毕业答辩前,同论文一起上交。译文字数不应少于3000个汉字。 2 书写规范 2.1 外文翻译的正文格式 正文版心设置为:上边距:3.5厘米,下边距:2.5厘米,左边距:3.5厘米,右边距:2厘米,页眉:2.5厘米,页脚:2厘米。 中文部分正文选用模板中的样式所定义的“正文”,每段落首行缩进2字;或者手动设置成每段落首行缩进2字,字体:宋体,字号:小四,行距:多倍行距1.3,间距:前段、后段均为0行。 这部分工作模板中已经自动设置为缺省值。 2.2标题格式 特别注意:各级标题的具体形式可参照外文原文确定。 1.第一级标题(如:第1章绪论)选用模板中的样式所定义的“标题1”,居左;或者手动设置成字体:黑体,居左,字号:三号,1.5倍行距,段后11磅,段前为11磅。 2.第二级标题(如:1.2 摘要与关键词)选用模板中的样式所定义的“标题2”,居左;或者手动设置成字体:黑体,居左,字号:四号,1.5倍行距,段后为0,段前0.5行。 3.第三级标题(如:1.2.1 摘要)选用模板中的样式所定义的“标题3”,居左;或者手动设置成字体:黑体,居左,字号:小四,1.5倍行距,段后为0,段前0.5行。 标题和后面文字之间空一格(半角)。 3 图表及公式等的格式说明 图表、公式、参考文献等的格式详见《吉林化工学院本科学生毕业设计说明书(论文)撰写规范及标准模版》中相关的说明。

本科毕业设计方案外文翻译范本

I / 11 本科毕业设计外文翻译 <2018届) 论文题目基于WEB 的J2EE 的信息系统的方法研究 作者姓名[单击此处输入姓名] 指导教师[单击此处输入姓名] 学科(专业 > 所在学院计算机科学与技术学院 提交日期[时间 ]

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Optimum blank design of an automobile sub-frame Jong-Yop Kim a ,Naksoo Kim a,*,Man-Sung Huh b a Department of Mechanical Engineering,Sogang University,Shinsu-dong 1,Mapo-ku,Seoul 121-742,South Korea b Hwa-shin Corporation,Young-chun,Kyung-buk,770-140,South Korea Received 17July 1998 Abstract A roll-back method is proposed to predict the optimum initial blank shape in the sheet metal forming process.The method takes the difference between the ?nal deformed shape and the target contour shape into account.Based on the method,a computer program composed of a blank design module,an FE-analysis program and a mesh generation module is developed.The roll-back method is applied to the drawing of a square cup with the ˉange of uniform size around its periphery,to con?rm its validity.Good agreement is recognized between the numerical results and the published results for initial blank shape and thickness strain distribution.The optimum blank shapes for two parts of an automobile sub-frame are designed.Both the thickness distribution and the level of punch load are improved with the designed blank.Also,the method is applied to design the weld line in a tailor-welded blank.It is concluded that the roll-back method is an effective and convenient method for an optimum blank shape design.#2000Elsevier Science S.A.All rights reserved. Keywords:Blank design;Sheet metal forming;Finite element method;Roll-back method

毕业论文 外文翻译#(精选.)

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毕业设计外文翻译

毕业设计(论文) 外文翻译 题目西安市水源工程中的 水电站设计 专业水利水电工程 班级 学生 指导教师 2016年

研究钢弧形闸门的动态稳定性 牛志国 河海大学水利水电工程学院,中国南京,邮编210098 nzg_197901@https://www.doczj.com/doc/7f10263506.html,,niuzhiguo@https://www.doczj.com/doc/7f10263506.html, 李同春 河海大学水利水电工程学院,中国南京,邮编210098 ltchhu@https://www.doczj.com/doc/7f10263506.html, 摘要 由于钢弧形闸门的结构特征和弹力,调查对参数共振的弧形闸门的臂一直是研究领域的热点话题弧形弧形闸门的动力稳定性。在这个论文中,简化空间框架作为分析模型,根据弹性体薄壁结构的扰动方程和梁单元模型和薄壁结构的梁单元模型,动态不稳定区域的弧形闸门可以通过有限元的方法,应用有限元的方法计算动态不稳定性的主要区域的弧形弧形闸门工作。此外,结合物理和数值模型,对识别新方法的参数共振钢弧形闸门提出了调查,本文不仅是重要的改进弧形闸门的参数振动的计算方法,但也为进一步研究弧形弧形闸门结构的动态稳定性打下了坚实的基础。 简介 低举升力,没有门槽,好流型,和操作方便等优点,使钢弧形闸门已经广泛应用于水工建筑物。弧形闸门的结构特点是液压完全作用于弧形闸门,通过门叶和主大梁,所以弧形闸门臂是主要的组件确保弧形闸门安全操作。如果周期性轴向载荷作用于手臂,手臂的不稳定是在一定条件下可能发生。调查指出:在弧形闸门的20次事故中,除了极特殊的破坏情况下,弧形闸门的破坏的原因是弧形闸门臂的不稳定;此外,明显的动态作用下发生破坏。例如:张山闸,位于中国的江苏省,包括36个弧形闸门。当一个弧形闸门打开放水时,门被破坏了,而其他弧形闸门则关闭,受到静态静水压力仍然是一样的,很明显,一个动态的加载是造成的弧形闸门破坏一个主要因素。因此弧形闸门臂的动态不稳定是造成弧形闸门(特别是低水头的弧形闸门)破坏的主要原是毫无疑问。

本科毕业设计外文翻译

Section 3 Design philosophy, design method and earth pressures 3.1 Design philosophy 3.1.1 General The design of earth retaining structures requires consideration of the interaction between the ground and the structure. It requires the performance of two sets of calculations: 1)a set of equilibrium calculations to determine the overall proportions and the geometry of the structure necessary to achieve equilibrium under the relevant earth pressures and forces; 2)structural design calculations to determine the size and properties of thestructural sections necessary to resist the bending moments and shear forces determined from the equilibrium calculations. Both sets of calculations are carried out for specific design situations (see 3.2.2) in accordance with the principles of limit state design. The selected design situations should be sufficiently Severe and varied so as to encompass all reasonable conditions which can be foreseen during the period of construction and the life of the retaining wall. 3.1.2 Limit state design This code of practice adopts the philosophy of limit state design. This philosophy does not impose upon the designer any special requirements as to the manner in which the safety and stability of the retaining wall may be achieved, whether by overall factors of safety, or partial factors of safety, or by other measures. Limit states (see 1.3.13) are classified into: a) ultimate limit states (see 3.1.3); b) serviceability limit states (see 3.1.4). Typical ultimate limit states are depicted in figure 3. Rupture states which are reached before collapse occurs are, for simplicity, also classified and

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附件1:外文资料翻译译文 包装对食品发展的影响 一个消费者对某个产品的第一印象来说包装是至关重要的,包括沟通的可取性,可接受性,健康饮食形象等。食品能够提供广泛的产品和包装组合,传达自己加工的形象感知给消费者,例如新鲜包装/准备,冷藏,冷冻,超高温无菌,消毒(灭菌),烘干产品。 食物的最重要的质量属性之一,是它的味道,其影响人类的感官知觉,即味觉和嗅觉。味道可以很大程度作退化的处理和/或扩展存储。其他质量属性,也可能受到影响,包括颜色,质地和营养成分。食品质量不仅取决于原材料,添加剂,加工和包装的方法,而且其预期的货架寿命(保质期)过程中遇到的分布和储存条件的质量。越来越多的竞争当中,食品生产商,零售商和供应商;和质量审核供应商有显着提高食品质量以及急剧增加包装食品的选择。这些改进也得益于严格的冷藏链中的温度控制和越来越挑剔的消费者。 保质期的一个定义是:在食品加工和包装组合下,在食品的容器和条件,在销售点分布在特定系统的时间能保持令人满意的食味品质。保质期,可以用来作为一个新鲜的概念,促进营销的工具。延期或保质期长的产品,还提供产品的使用时间,方便以及减少浪费食物的风险,消费者和/或零售商。包装产品的质量和保质期的主题是在第3章中详细讨论。 包装为消费者提供有关产品的重要信息,在许多情况下,使用的包装和/或产品,包括事实信息如重量,体积,配料,制造商的细节,营养价值,烹饪和开放的指示,除了法律准则的最小尺寸的文字和数字,有定义的各类产品。消费者寻求更详细的产品信息,同时,许多标签已经成为多语种。标签的可读性是为视障人士的问题,这很可能成为一个对越来越多的老年人口越来越重要的问题。 食物的选择和包装创新的一个主要驱动力是为了方便消费者的需求。这里有许多方便的现代包装所提供的属性,这些措施包括易于接入和开放,处置和处理,产品的知名度,再密封性能,微波加热性,延长保质期等。在英国和其他发达经济体显示出生率下降和快速增长的一个相对富裕的老人人口趋势,伴随着更加苛

毕业论文外文翻译模板

农村社会养老保险的现状、问题与对策研究社会保障对国家安定和经济发展具有重要作用,“城乡二元经济”现象日益凸现,农村社会保障问题客观上成为社会保障体系中极为重要的部分。建立和完善农村社会保障制度关系到农村乃至整个社会的经济发展,并且对我国和谐社会的构建至关重要。我国农村社会保障制度尚不完善,因此有必要加强对农村独立社会保障制度的构建,尤其对农村养老制度的改革,建立健全我国社会保障体系。从户籍制度上看,我国居民养老问题可分为城市居民养老和农村居民养老两部分。对于城市居民我国政府已有比较充足的政策与资金投人,使他们在物质和精神方面都能得到较好地照顾,基本实现了社会化养老。而农村居民的养老问题却日益突出,成为摆在我国政府面前的一个紧迫而又棘手的问题。 一、我国农村社会养老保险的现状 关于农村养老,许多地区还没有建立农村社会养老体系,已建立的地区也存在很多缺陷,运行中出现了很多问题,所以完善农村社会养老保险体系的必要性与紧迫性日益体现出来。 (一)人口老龄化加快 随着城市化步伐的加快和农村劳动力的输出,越来越多的农村青壮年人口进入城市,年龄结构出现“两头大,中间小”的局面。中国农村进入老龄社会的步伐日渐加快。第五次人口普查显示:中国65岁以上的人中农村为5938万,占老龄总人口的67.4%.在这种严峻的现实面前,农村社会养老保险的徘徊显得极其不协调。 (二)农村社会养老保险覆盖面太小 中国拥有世界上数量最多的老年人口,且大多在农村。据统计,未纳入社会保障的农村人口还很多,截止2000年底,全国7400多万农村居民参加了保险,占全部农村居民的11.18%,占成年农村居民的11.59%.另外,据国家统计局统计,我国进城务工者已从改革开放之初的不到200万人增加到2003年的1.14亿人。而基本方案中没有体现出对留在农村的农民和进城务工的农民给予区别对待。进城务工的农民既没被纳入到农村养老保险体系中,也没被纳入到城市养老保险体系中,处于法律保护的空白地带。所以很有必要考虑这个特殊群体的养老保险问题。

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