英文文献及翻译

英文文献：

The application of e-commerce for SMEs

A great advantage of e-commerce is not only suitable for use in large enterprises, but also very beneficial to many small and medium enterprises. Relative to large enterprises, small and medium enterprises of human, financial, information technology, weak and small and medium enterprises to apply e-commerce is a new topic to be studied. Typically, the use of e-commerce has four types: information access, personal communication, shopping services, virtual enterprises.As e-commerce is a complex system engineering, it will use many new technologies, but the most important thing is the following: Electronic Data Interchange (EDI), bar codes, e-mail, Internet, WorldWideWeb, product data exchange and electronic form. The benefits of e-commerce use by SMEsFor small and medium sized e-commerce can give them to bring many new opportunities and challenges facing SMEs it can solve many difficulties and problems. The arrival of Internet for SMEs to open up a broader market space. As the information in the enterprise's competitive edge competitive play an increasingly important role, with e-commerce, information on SMEs and big business competition. Overall, the impact of electronic commerce for small and medium enterprises can be divided into the following areas: 1. Global markets, the competitiveness of SMEs traditional market can be strengthened; SMEs have more opportunities to sell the products to various countries and regions worldwide. 2. Market supply chain suppliers to provide design and engineering services required will increase; manufacturers will outsource more non-core businesses; customers will need more electronic communication for use in orders, billing and other business, when large

customers that request, which will have a big impact the supply chain; customers will require their suppliers to provide more inventory management services, such as data warehouse and order management; manufacturers will continue to reduce the total number of suppliers; supply chain links between the companies will more closely. 3. Internal operations and process control with greater use of networked information technology and system integration technology, the company will improve communications and collaboration; will use more automated manufacturing technology for integrating external data and internal operations to provide greater opportunities, such as EDI and MRP systems integration; enterprises will reduce the number of employees, but will increase the workload of each employee; business operations and management costs will be reduced.4. Customer service providers will try to shorten the manufacturing of new products and services of their available time; manufacturers will try to minimize the price; product quality will be greater attention; suppliers will find a need for faster and better to provide order status information (such as the production date); businesses will pay more attention to the product after-sales service; information and telecommunications services, competition will intensify between; available to manufacturers of information and the types of telecommunications services will increase; The new e-commerce products and services will appear; human resources and work structure; computer's role in the enterprise will become more important; small company in training employees to use computers, the more difficult than those of large companies. 5. Information as business assets, the information itself will become an important marketable commodities (such as databases); company data in decision-making will play an important role; through

networking, manufacturers will have more and better opportunities to access more widely useful in commercial and technical information. 6. Small business prospects and timely use of the network can access the latest business trends information to guide their production and sales. Determine the feasibility of e-commerce technology When SMEs decide to use e-commerce, it is necessary to meet these business needs to determine the technical feasibility of the various e-business initiatives. A basic principle is to use the most it can increase the operational capacity of e-commerce technology. Here are the most suitable technology for each number of e-commerce applications, can be used for small and medium enterprises in the choice of reference. 1.EDI the structured data into other Yingyong in (such as the use of customer orders to install the product); when the transaction volume can reduce costs; allow the trading of many Butong Huoban (such as customers, suppliers, manufacturers, etc.) trade between easier.2. Barcodes quickly determine and identify the merchandise; to determine the identity and integration into other applications and databases.3. E-mail to individuals or groups to provide free inquiry and exchange; need to send some simple information sharing to all members of the enterprise; by additional document (attachment) to share complex information; to make long-distance collaboration faster and more convenient.4.WorldWideWeb published information about the company to achieve the purpose of publicity companies; from a large number of data sources to retrieve information; e-commerce to buy / sell goods or services; collaboration between multiple users or information sharing.5. Product data exchange needs to be timely product information sent to trading partners; distance together with partners in product design.6. Spreadsheet better way to format a norm

concerning the management of data; when it comes to many different tasks simultaneously can track the entire process; artificial input data with data on the machine itself is integrated with; by integration of WWW and the implementation of internal systems to facilitate electronic commerce.Several issues should be notedRelative to large enterprises, small and medium enterprises in human, financial, information technology, weaker, and therefore the process of implementing e-commerce there are some issues warrant particular attention, even small enterprises need on the e-commerce system level of view, this process is very important.When companies feel the need of enterprise systems from anywhere in the process started e-commerce can make use of existing commercial enterprises or technology, you can also e-business from scratch for system-level planning and design. If the enterprise may resolve how to deal with excess inventory when the thought of starting e-commerce, while another company might choose through the implementation of e-commerce strategies to improve customer service levels. This is the advantage of a flexible small and medium enterprises, and large enterprises is different, in order to conduct e-commerce system-level on the need for comprehensive planning.

For small and medium terms, system-level programs can also be achieved at various stages of e-commerce start. Even if some companies have implemented e-commerce systems can also be quickly modified.For e-commerce may return to the business benefits to be in the business consequences and evaluate the technical feasibility of both. These two aspects will affect the implementation of e-business attitude and determination. One pair of their competition in the market its ability to company not necessarily can do it

well the new e-commerce technology,While the other wants to use the new e-commerce tools to expand their competitive advantage of companies, the pace of implementation of e-commerce may be larger.Because electronic commerce is a systematic project, required before the decision to use it make sure to do so can give enterprises the greatest benefits and minimum adverse effects, most important is to ensure the implementation of e-commerce can bring to the moreenterprise of interest returns.

中文翻译：

中小企业如何应用电子商务

电子商务的一个很大的优点是它不仅适合于大企业使用，而且对众多的中小企业也非常有利。相对于大型企业来说，中小型企业的人力、财力、信息技术实力较弱，中小企业如何应用电子商务是一个值得研究的新课题。

通常情况下，电子商务的用途具有四种类型：信息访问、个人通信、购物服务、虚拟企业。

由于电子商务是一个复杂的系统工程，因此它会用到许多新的技术，但最重要的还是以下几种：电子数据交换（EDI）、条形码、电子邮件、Internet、WorldWideWeb、产品数据交换和电子表格。

中小企业使用电子商务的好处：

对于中小企业来讲，电子商务能给它们带来许多新的机遇和挑战，它能够解决中小企业面临的许多困难和问题。Internet的到来可以为中小企业开辟更广泛的市场空间。由于信息

的竞争在企业的竞争优势中发挥着越来越重要的作用，有了电子商务，中小企业在信息方面就能够与大企业竞争。总的来讲，电子商务对中小企业带来的影响可以分为以下几个方面：1.全球市场

中小企业传统市场的竞争力可以得到加强；中小企业有更多的机会将产品销售到全球各个国家和地区。

2.市场供应链

对供应商提供设计和工程服务的要求将增加；厂商将外包更多的非核心业务；客户将需要更多的电子通信以用于下订单、记账等业务，当大的客户有这种要求时，这将对供应链产生大的影响；客户将要求他们的供应商提供更多的存货管理服务，如数据仓库和订单管理；制造商将继续减少供应商的总数量；供应链中各公司之间的联系将更加紧密。

3.内部操作和过程控制

随着更多地使用联网信息技术和系统集成技术，公司内的通信和协作将改进；将更多地使用自动化制造技术，为集成外部数据和内部操作提供更大的机会，如EDI和MRP系统的集成；企业雇员的数量将减少，但每个雇员的工作量将增加；企业的操作和管理成本将减少。

4.客户服务

制造商将试图缩短它们的新产品和服务面世的时间；制造商将试图将价格降到最低；产品质量将受到更大的重视；供应商将会发现有必要更好更快地提供有关订单状态的信息（如产品的生产日期等）；商家将会更加重视产品的售后服务；信息和电信服务之间的竞争将加剧；提供给制造商的信息和电信服务的种类将增加；新的电子商务产品和服务将出现；人力资源和工作结构；计算机在企业中的作用将更加重要；小公司在训练员工使用计算机方面，将比大公司更困难些。

5.信息作为商业资产

论文外文文献翻译3000字左右

南京航空航天大学金城学院 毕业设计（论文）外文文献翻译 系部经济系 专业国际经济与贸易 学生姓名陈雅琼学号2011051115 指导教师邓晶职称副教授 2015年5月

Economic policy,tourism trade and productive diversification （Excerpt） Iza Lejárraga,Peter Walkenhorst The broad lesson that can be inferred from the analysis is that promoting tourism linkages with the productive capabilities of a host country is a multi-faceted approach influenced by a variety of country conditions.Among these,fixed or semi-fixed factors of production,such as land,labor,or capital,seem to have a relatively minor influence.Within the domain of natural endowments,only agricultural capital emerged as significant.This is a result that corresponds to expectations,given that foods and beverages are the primary source of demand in the tourism economy.Hence,investments in agricultural technology may foment linkages with the tourism market.It is also worth mentioning that for significant backward linkages to emerge with local agriculture,a larger scale of tourism may be important. According to the regression results,a strong tourism–agriculture nexus will not necessarily develop at a small scale of tourism demand. It appears that variables related to the entrepreneurial capital of the host economy are of notable explanatory significance.The human development index(HDI), which is used to measure a country's general level of development,is significantly and positively associated with tourism linkages.One plausible explanation for this is that international tourists,who often originate in high-income countries,may feel more comfortable and thus be inclined to consume more in a host country that has a life-style to which they can relate easily.Moreover,it is important to remember that the HDI also captures the relative achievements of countries in the level of health and education of the population.Therefore,a higher HDI reflects a healthier and more educated workforce,and thus,the quality of local entrepreneurship.Related to this point,it is important to underscore that the level of participation of women in the host economy also has a significantly positive effect on linkages.In sum, enhancing local entrepreneurial capital may expand the linkages between tourism and other sectors of the host country.

快速外文文献翻译

快速外文文献翻译 在科研过程中阅读翻译外文文献是一个非常重要的环节，许多领域高水平的文献都是外文文献，借鉴一些外文文献翻译的经验是非常必要的。由于特殊原因我翻译外文文献的机会比较多，慢慢地就发现了外文文献翻译过程中的三大利器：Google“翻译”频道、金山词霸（完整版本）和CNKI“翻译助手"。 具体操作过程如下： 1.先打开金山词霸自动取词功能，然后阅读文献； 2.遇到无法理解的长句时，可以交给Google处理，处理后的结果猛一看，不堪入目，可是经过大脑的再处理后句子的意思基本就明了了； 3.如果通过Google仍然无法理解，感觉就是不同，那肯定是对其中某个“常用单词”理解有误，因为某些单词看似很简单，但是在文献中有特殊的意思，这时就可以通过CNKI的“翻译助手”来查询相关单词的意思，由于CNKI的单词意思都是来源与大量的文献，所以它的吻合率很高。 另外，在翻译过程中最好以“段落”或者“长句”作为翻译的基本单位，这样才不会造成“只见树木，不见森林”的误导。 注： 1、Google翻译：https://www.wendangku.net/doc/b71124014.html,/language_tools google，众所周知，谷歌里面的英文文献和资料还算是比较详实的。我利用它是这样的。一方面可以用它查询英文论文，当然这方面的帖子很多，大家可以搜索，在此不赘述。回到我自己说的翻译上来。下面给大家举个例子来说明如何用吧比如说“电磁感应透明效应”这个词汇你不知道他怎么翻译， 首先你可以在CNKI里查中文的，根据它们的关键词中英文对照来做，一般比较准确。 在此主要是说在google里怎么知道这个翻译意思。大家应该都有词典吧，按中国人的办法，把一个一个词分着查出来，敲到google里，你的这种翻译一般不太准，当然你需要验证是否准确了，这下看着吧，把你的那支离破碎的翻译在google里搜索，你能看到许多相关的文献或资料，大家都不是笨蛋，看看，也就能找到最精确的翻译了，纯西式的！我就是这么用的。 2、CNKI翻译：https://www.wendangku.net/doc/b71124014.html, CNKI翻译助手，这个网站不需要介绍太多，可能有些人也知道的。主要说说它的有点，你进去看看就能发现：搜索的肯定是专业词汇，而且它翻译结果下面有文章与之对应（因为它是CNKI检索提供的，它的翻译是从文献里抽出来的），很实用的一个网站。估计别的写文章的人不是傻子吧，它们的东西我们可以直接拿来用，当然省事了。网址告诉大家，有兴趣的进去看看，你们就会发现其乐无穷！还是很值得用的。https://www.wendangku.net/doc/b71124014.html, 3、网路版金山词霸（不到1M）：https://www.wendangku.net/doc/b71124014.html,/6946901637944806 翻译时的速度： 这里我谈的是电子版和打印版的翻译速度，按个人翻译速度看，打印版的快些，因为看电子版本一是费眼睛，二是如果我们用电脑，可能还经常时不时玩点游戏，或者整点别的，导致最终SPPEED变慢，再之电脑上一些词典（金山词霸等）在专业翻译方面也不是特别好，所以翻译效果不佳。在此本人建议大家购买清华大

外文文献及翻译

外文文献及翻译 题目：利用固定化过氧化氢酶 回收纺织品漂染的废水 专业食品科学与工程 学生姓名梁金龙 班级B食品072 学号0710308119 指导教师郑清

利用固定化过氧化氢酶回收纺织品漂染的废水 Silgia A. Costa1, Tzanko Tzanov1, Filipa Carneiro1, Georg M. Gübitz2 &Artur Cavaco-Paulo1,? 1纺织工程系, 米尼奥大学, 4810吉马尔, 葡萄牙 2环境生物技术系, 格拉茨技术大学, 8010格拉茨, 奥地利 ?作者联系方式(Fax: +351 253 510293; E-mail: artur@det.uminho.pt) 关键词：过氧化氢酶的固定化，酶稳定，过氧化氢，纺织印染 摘要 过氧化氢酶固定在氧化铝载体上并用戊二醛交联，在再循环塔反应器和CSTR反应器中研究贮存稳定性，温度和pH值对酶的活性。固定化酶的在的活性维持在44％，pH值11（30?C），对照组是活性为90％，pH值7（80?C），过氧化氢酶固定化的半衰期时间被提高到2小时（pH12，60?C）。用过氧化氢漂白织物后，洗涤过程中的残留水被固定化酶处理，可以用于再次印染时，记录实验数据。 1 序言 由于新的法规的出台，从生态经济的角度来看（Dickinson1984年），对于纺织行业中存在的成本和剩余水域的污染问题，必须给予更多的关注。过氧化氢是一种漂白剂，广泛应用于工业纺织工艺（Spiro & Griffith1997年）。在去除H2O2时，会消耗大量的水和能源（Weck 1991, St?hr & Petry 1995），以避免对氧气敏感的染料（Jensen 2000）产生后续问题。过氧化氢酶可用于降低过氧化氢的含量（Vasudevan & Thakur 1994, Emerson et al. 1996），从而减少水分消耗或方便回收印染洗涤液。过氧化氢酶的使用主要问题出在漂白时温度和清洗液碱度过高。以前，我们试图通过筛选新的嗜热嗜碱的微生物（Paar et al. 2001）或使用不同的酶稳定剂（Costa et al. 2001）来解决此问题。但是染料与蛋白质之间的潜在相互作用（Tzanov et al. 2001a, b）表明，可溶性过氧化氢酶的使用是不恰当的。固定化过氧化氢酶的使用还有一种选择(Costa et al. 2001, Amar et al. 2000)。在这项研究中，我们对氧化铝进行共价固定并使用戊二醛作为交联剂，这种方法在商业中得到验证。本项研究的目的就是探讨过氧化氢酶的固定化动力学，及其稳定性和工艺条件，这将使我们能够应用此系统，以处理可能被用于清洗染色的反复使用的酒。 2 材料和方法 2.1 酶 Terminox（EC1.11.1.6），50L以上，由AQUITEX- Maia提供，葡萄牙产。 2.2 过氧化氢酶的固定化 取Al2O3颗粒或薄片（Aldrich），直径分别为3和7毫米，在45摄氏度下，先经浓度4%的γ-氨丙基三乙氧基硅烷(Sigma)烷基化，再放入丙酮中浸泡24小时。用蒸馏水洗涤硅烷化载体后，放入浓度为2％戊二醛水溶液中室温下浸泡2小时（Aldrich），重复清洗一次并在60?C下干燥1小时。取五克的烷基化载体，室温24?C下浸泡在25毫升粗酶制剂中（Costa et al. 2001）。得出，每克Al2O3

毕业论文英文参考文献与译文

Inventory management Inventory Control On the so-called "inventory control", many people will interpret it as a "storage management", which is actually a big distortion. The traditional narrow view, mainly for warehouse inventory control of materials for inventory, data processing, storage, distribution, etc., through the implementation of anti-corrosion, temperature and humidity control means, to make the custody of the physical inventory to maintain optimum purposes. This is just a form of inventory control, or can be defined as the physical inventory control. How, then, from a broad perspective to understand inventory control? Inventory control should be related to the company's financial and operational objectives, in particular operating cash flow by optimizing the entire demand and supply chain management processes (DSCM), a reasonable set of ERP control strategy, and supported by appropriate information processing tools, tools to achieved in ensuring the timely delivery of the premise, as far as possible to reduce inventory levels, reducing inventory and obsolescence, the risk of devaluation. In this sense, the physical inventory control to achieve financial goals is just a means to control the entire inventory or just a necessary part; from the perspective of organizational functions, physical inventory control, warehouse management is mainly the responsibility of The broad inventory control is the demand and supply chain management, and the whole company's responsibility. Why until now many people's understanding of inventory control, limited physical inventory control? The following two reasons can not be ignored: First, our enterprises do not attach importance to inventory control. Especially those who benefit relatively good business, as long as there is money on the few people to consider the problem of inventory turnover. Inventory control is simply interpreted as warehouse management, unless the time to spend money, it may have been to see the inventory problem, and see the results are often very simple procurement to buy more, or did not do warehouse departments . Second, ERP misleading. Invoicing software is simple audacity to call it ERP, companies on their so-called ERP can reduce the number of inventory, inventory control, seems to rely on their small software can get. Even as SAP, BAAN ERP world, the field of

java毕业论文外文文献翻译

Advantages of Managed Code Microsoft intermediate language shares with Java byte code the idea that it is a low-level language witha simple syntax , which can be very quickly translated intonative machine code. Having this well-defined universal syntax for code has significant advantages. Platform independence First, it means that the same file containing byte code instructions can be placed on any platform; atruntime the final stage of compilation can then be easily accomplished so that the code will run on thatparticular platform. In other words, by compiling to IL we obtain platform independence for .NET, inmuch the same way as compiling to Java byte code gives Java platform independence. Performance improvement IL is actually a bit more ambitious than Java bytecode. IL is always Just-In-Time compiled (known as JIT), whereas Java byte code was ofteninterpreted. One of the disadvantages of Java was that, on execution, the process of translating from Javabyte code to native executable resulted in a loss of performance. Instead of compiling the entire application in one go (which could lead to a slow start-up time), the JITcompiler simply compiles each portion of code as it is called (just-in-time). When code has been compiled.once, the resultant native executable is stored until the application exits, so that it does not need to berecompiled the next time that portion of code is run. Microsoft argues that this process is more efficientthan compiling the entire application code at the start, because of the likelihood that large portions of anyapplication code will not actually be executed in any given run. Using the JIT compiler, such code willnever be compiled.

英文文献翻译

中等分辨率制备分离的 快速色谱技术 W. Clark Still,* Michael K a h n , and Abhijit Mitra Departm(7nt o/ Chemistry, Columbia Uniuersity,1Veu York, Neu; York 10027 ReceiLied January 26, 1978 我们希望找到一种简单的吸附色谱技术用于有机化合物的常规净化。这种技术是适于传统的有机物大规模制备分离，该技术需使用长柱色谱法。尽管这种技术得到的效果非常好，但是其需要消耗大量的时间，并且由于频带拖尾经常出现低复原率。当分离的样本剂量大于1或者2g时，这些问题显得更加突出。近年来，几种制备系统已经进行了改进，能将分离时间减少到1-3h，并允许各成分的分辨率ΔR f≥（使用薄层色谱分析进行分析）。在这些方法中，在我们的实验室中，媒介压力色谱法1和短柱色谱法2是最成功的。最近，我们发现一种可以将分离速度大幅度提升的技术，可用于反应产物的常规提纯，我们将这种技术称为急骤色谱法。虽然这种技术的分辨率只是中等（ΔR f≥），而且构建这个系统花费非常低，并且能在10-15min内分离重量在的样本。4 急骤色谱法是以空气压力驱动的混合介质压力以及短柱色谱法为基础，专门针对快速分离，介质压力以及短柱色谱已经进行了优化。优化实验是在一组标准条件5下进行的，优化实验使用苯甲醇作为样本，放在一个20mm*5in.的硅胶柱60内，使用Tracor 970紫外检测器监测圆柱的输出。分辨率通过持续时间（r）和峰宽（w,w/2）的比率进行测定的（Figure 1），结果如图2-4所示，图2-4分别放映分辨率随着硅胶颗粒大小、洗脱液流速和样本大小的变化。

英文文献及中文翻译

毕业设计说明书 英文文献及中文翻译 学院：专 2011年6月 电子与计算机科学技术软件工程

https://www.wendangku.net/doc/b71124014.html, Overview https://www.wendangku.net/doc/b71124014.html, is a unified Web development model that includes the services necessary for you to build enterprise-class Web applications with a minimum of https://www.wendangku.net/doc/b71124014.html, is part of https://www.wendangku.net/doc/b71124014.html, Framework,and when coding https://www.wendangku.net/doc/b71124014.html, applications you have access to classes in https://www.wendangku.net/doc/b71124014.html, Framework.You can code your applications in any language compatible with the common language runtime(CLR), including Microsoft Visual Basic and C#.These languages enable you to develop https://www.wendangku.net/doc/b71124014.html, applications that benefit from the common language runtime,type safety, inheritance,and so on. If you want to try https://www.wendangku.net/doc/b71124014.html,,you can install Visual Web Developer Express using the Microsoft Web Platform Installer,which is a free tool that makes it simple to download,install,and service components of the Microsoft Web Platform.These components include Visual Web Developer Express,Internet Information Services (IIS),SQL Server Express,and https://www.wendangku.net/doc/b71124014.html, Framework.All of these are tools that you use to create https://www.wendangku.net/doc/b71124014.html, Web applications.You can also use the Microsoft Web Platform Installer to install open-source https://www.wendangku.net/doc/b71124014.html, and PHP Web applications. Visual Web Developer Visual Web Developer is a full-featured development environment for creating https://www.wendangku.net/doc/b71124014.html, Web applications.Visual Web Developer provides an ideal environment in which to build Web sites and then publish them to a hosting https://www.wendangku.net/doc/b71124014.html,ing the development tools in Visual Web Developer,you can develop https://www.wendangku.net/doc/b71124014.html, Web pages on your own computer.Visual Web Developer includes a local Web server that provides all the features you need to test and debug https://www.wendangku.net/doc/b71124014.html, Web pages,without requiring Internet Information Services(IIS)to be installed. Visual Web Developer provides an ideal environment in which to build Web sites and then publish them to a hosting https://www.wendangku.net/doc/b71124014.html,ing the development tools in Visual Web Developer,you can develop https://www.wendangku.net/doc/b71124014.html, Web pages on your own computer.

外文文献及翻译

文献翻译 原文 Combining JSP and Servlets The technology of JSP and Servlet is the most important technology which use Java technology to exploit request of server, and it is also the standard which exploit business application .Java developers prefer to use it for a variety of reasons, one of which is already familiar with the Java language for the development of this technology are easy to learn Java to the other is "a preparation, run everywhere" to bring the concept of Web applications, To achieve a "one-prepared everywhere realized." And more importantly, if followed some of the principles of good design, it can be said of separating and content to create high-quality, reusable, easy to maintain and modify the application. For example, if the document in HTML embedded Java code too much (script), will lead the developed application is extremely complex, difficult to read, it is not easy reuse, but also for future maintenance and modification will also cause difficulties. In fact, CSDN the JSP / Servlet forum, can often see some questions, the code is very long, can logic is not very clear, a large number of HTML and Java code mixed together. This is the random development of the defects. Early dynamic pages mainly CGI (Common Gateway Interface, public Gateway Interface) technology, you can use different languages of the CGI programs, such as VB, C / C + + or Delphi, and so on. Though the technology of CGI is developed and powerful, because of difficulties in programming, and low efficiency, modify complex shortcomings, it is gradually being replaced by the trend. Of all the new technology, JSP / Servlet with more efficient and easy to program, more powerful, more secure and has a good portability, they have been many people believe that the future is the most dynamic site of the future development of technology. Similar to CGI, Servlet support request / response model. When a customer submit a request to the server, the server presented the request Servlet, Servlet responsible for handling requests and generate a response, and then gave the server, and then from the server sent to

毕业论文5000字英文文献翻译

英文翻译 英语原文： . Introducing Classes The only remaining feature we need to understand before solving our bookstore problem is how to write a data structure to represent our transaction data. In C++ we define our own data structure by defining a class. The class mechanism is one of the most important features in C++. In fact, a primary focus of the design of C++ is to make it possible to define class types that behave as naturally as the built-in types themselves. The library types that we've seen already, such as istream and ostream, are all defined as classesthat is,they are not strictly speaking part of the language. Complete understanding of the class mechanism requires mastering a lot of information. Fortunately, it is possible to use a class that someone else has written without knowing how to define a class ourselves. In this section, we'll describe a simple class that we canuse in solving our bookstore problem. We'll implement this class in the subsequent chapters as we learn more about types,expressions, statements, and functionsall of which are used in defining classes. To use a class we need to know three things: What is its name? Where is it defined? What operations does it support? For our bookstore problem, we'll assume that the class is named Sales_item and that it is defined in a header named Sales_item.h. The Sales_item Class The purpose of the Sales_item class is to store an ISBN and keep track of the number of copies sold, the revenue, and average sales price for that book. How these data are stored or computed is not our concern. To use a class, we need not know anything about how it is implemented. Instead, what we need to know is what operations the class provides. As we've seen, when we use library facilities such as IO, we must include the associated headers. Similarly, for our own classes, we must make the definitions associated with the class available to the compiler. We do so in much the same way. Typically, we put the class definition into a file. Any program that wants to use our class must include that file. Conventionally, class types are stored in a file with a name that, like the name of a program source file, has two parts: a file name and a file suffix. Usually the file name is the same as the class defined in the header. The suffix usually is .h, but some programmers use .H, .hpp, or .hxx. Compilers usually aren't picky about header file names, but IDEs sometimes are. We'll assume that our class is defined in a file named Sales_item.h. Operations on Sales_item Objects

文献综述,外文翻译,论文网站

文献综述怎么写 1) 什么是文献综述? 文献综述是研究者在其提前阅读过某一主题的文献后，经过理解、整理、融会贯通，综合分析和评价而组成的一种不同于研究论文的文体。 2) 文献综述的写作要求 1、文献综述的格式 文献综述的格式与一般研究性论文的格式有所不同。这是因为研究性的论文注重研究的方法和结果，而文献综述介绍与主题有关的详细资料、动态、进展、展望以及对以上方面的评述。因此文献综述的格式相对多样，但总的来说，一般都包含以下四部分：即前言、主题、总结和参考文献。撰写文献综述时可按这四部分拟写提纲，再根据提纲进行撰写工作。 前言，要用简明扼要的文字说明写作的目的、必要性、有关概念的定义，综述的范围，阐述有关问题的现状和动态，以及目前对主要问题争论的焦点等。前言一般200-300字为宜，不宜超过500字。 正文，是综述的重点，写法上没有固定的格式，只要能较好地表达综合的内容，作者可创造性采用诸多形式。正文主要包括论据和论证两个部分，通过提出问题、分析问题和解决问题，比较不同学者对同一问题的看法及其理论依据，进一步阐明问题的来龙去脉和作者自己的见解。当然，作者也可从问题发生的历史背景、目前现状、发展方向等提出文献的不同观点。正文部分可根据内容的多少可分为若干个小标题分别论述。 小结，是结综述正文部分作扼要的总结，作者应对各种观点进行综合评价，提出自己的看法，指出存在的问题及今后发展的方向和展望。内容单纯的综述也可不写小结。 参考文献，是综述的重要组成部分。一般参考文献的多少可体现作者阅读文献的广度和深度。对综述类论文参考文献的数量不同杂志有不同的要求，一般以30条以内为宜，以最近3-5年内的最新文献为主。 2、文献综述规定 1. 为了使选题报告有较充分的依据，要求硕士研究生在论文开题之前作文献综述。 2. 在文献综述时，研究生应系统地查阅与自己的研究方向有关的国内外文献。通常阅读文献不少于30篇，且文献搜集要客观全面 3. 在文献综述中，研究生应说明自己研究方向的发展历史，前人的主要研究成果，存在的问题及发展趋势等。 4. 文献综述要条理清晰，文字通顺简练。 5. 资料运用恰当、合理。文献引用用方括号[ ]括起来置于引用词的右上角。 6. 文献综述中要有自己的观点和见解。不能混淆作者与文献的观点。鼓励研究生多发现问题、多提出问题、并指出分析、解决问题的可能途径，针对性强。 7. 文献综述不少于3000字。 3、注意事项 ⒈搜集文献应尽量全。掌握全面、大量的文献资料是写好综述的前提，否则，随便搜集一点资料就动手撰写是不可能写出好的综述。 ⒉注意引用文献的代表性、可靠性和科学性。在搜集到的文献中可能出现观点雷同，有的文献在可靠性及科学性方面存在着差异，因此在引用文献时应注意选用代表性、可靠性和科学性较好的文献。 ⒊引用文献要忠实文献内容。由于文献综述有作者自己的评论分析，因此在撰写时应分清作者的观点和文献的内容，不能篡改文献的内容。引用文献不过多。文献综述的作者引用间接文献的现象时有所见。如果综述作者从他人引用的参考文献转引过来，这些文献在他人

英文文献及其翻译

步进电机的知识 什么是步进电机： 步进电机是一种把电脉冲转化为角位移的执行机构。通俗的说：当驱动程序收到一个步进脉冲信号，将驱动步进电机轴旋转一个固定的角度（步进角）。您可以通过控制脉冲个数来控制角位移，从而达到准确定位的目的;同时，你可以通过控制脉冲频率来控制电机的旋转速度和加速度，实现速度控制的目的。 步进电机的种类： 步进电机分为三种：永磁式（PM），反应式（VR）和混合式（HR）永磁式步进电机一般为两相，转矩和体积较小，步进角一步7.5度或15度;反应式一般有三相可以实现大转矩输出，步进角一般是1.5度，但噪声和振动大。在欧洲和美洲80个国家已被淘汰;混合式步进是混合了永磁式和反应的优势。它由两相和五相：一般两相的步距角是1.8度，而的五相步距角为0.72度。是使用最广泛的的步进电机。 步进电机允许的最高表面温度 步进电机温度过高首先会的磁性材料退磁，导致转矩降低甚至失步，电机表面温度允许的最大值取决于的磁性材料退磁点;一般来说，磁性材料退磁点在摄氏130度以上有些材料甚至高达摄氏200度高，所以步进电机表面温度在摄氏80-90度是正常的。 步进电机精度为多少？是否累积 一般步进电机的精度为步进角的3-5%，且不累积 如何确定步进电机驱动器直流电源 A.电压确定 混合式步进电机驱动器的电源电压范围较广（比如IM483的供电电压12?48VDC），电源电压通常根据电机的转速和响应要求来选择。如果要求较快的运行速度较高的响应速度就选用较高的电压，但注意电源电压的峰值不能超过驱动器的最大输入电压，否则可能会损坏驱动器。 B.电流确定 电源电流一般根据输出相电流I来确定。如果采用线性电源，电源电流一般可取I的1.1?1.3倍;如果采用开关电源，电源电流一般可取I的1.5?2.0倍。 步进电机的主要特性 在步进电机关机时要确保没有脉冲信号，当电机运行时 如果加入适当的脉冲信号，它会转过一定的角度（称为步距角是）。转速与脉冲频率成正比。 2龙式步进电机步距角7.5度，旋转360度，需要48个脉冲来完成。 3步进电机具有快速启动和停止的优良特性。 4只要改变脉冲，可以很容易地改变电机轴旋转的方向。 因此，目前的打印机，绘图仪，机器人设备以步进电机作为动力核心。 步进电机控制的例子 我们以四相单极步进电机为例： 四个相绕组引出四个相和两个公共线（连接到正极）。一相接地。会被激发，。我们使用四相八拍控制，即第1阶段第2阶段交替反过来，会提高分辨率。步距角0.9°，可以转移到控制电机励磁是为了转移如下： 如果电机反转的要求，传输的激励信号可以逆转的。2控制方案 控制系统框图如下