信息系统信息技术中英文对照外文翻译文献

中英文资料外文翻译文献

Information Systems Outsourcing Life Cycle And Risks Analysis 1. Introduction

Information systems outsourcing has obtained tremendous attentions in the information technology industry.Although there are a number of reasons for companies to pursuing information systems (IS)outsourcing , the most prominent motivation for IS outsourcing that revealed in the literatures was “cost saving”. Costfactor has been a major decision factors for IS outsourcing.

Other than cost factor, there are other reasons for outsourcing decision.The Outsourcing Institute surveyed outsourcing end-users from their membership in 1998 and found that top 10 reasons companies outsource were:

Reduce and control operating costs,improve company focus,gain access to world-class capabilities,free internal resources for other purposes, resources are not available internally, accelerate reengineering benefits, function difficult to manage/out of control,make capital funds available, share risks, and cash infusion.

Within these top ten outsourcing reasons, there are three items that related to financial concerns, they are operating costs, capital funds available, and cash infusion. Since the phenomenon of wage difference exists in the outsourced countries, it is obvious that outsourcing companies would save remarkable amount of labor cost.According to Gartner, Inc.'s report, world business outsourcing services would grow from $110 billion in 2002 to $173 billion in 2007,a proximately 9.5% annual growth rate.

In addition to cost saving concern, there are other factors that influence outsourcing decision, including the awareness of success and risk factors, the outsourcing risks identification and management,and the project quality management. Outsourcing activities are substantially complicated and outsourcing project usually carries a huge array of risks. Unmanaged outsourcing risks will increase total project cost, devaluate

software quality, delay project completion time, and finally lower the success rate of the outsourcing project.Outsourcing risks have been discovered in areas such as unexpected transition and management costs, switching costs, costly contractual amendments, disputes and litigation, service debasement, cost escalation, loss of organizational competence, hidden service costs,and so on.

Most published outsourcing studies focused on organizational and managerial issues. We believe that IS outsourcing projects embrace various risks and uncertainty that may inhibit the chance of outsourcing success. In addition to service and management related risk issues, we feel that technical issues that restrain the degree of outsourcing success may have been overlooked. These technical issues are project management, software quality, and quality assessment methods that can be used to implement IS outsourcing projects.Unmanaged risks generate loss. We intend to identify the technical risks during outsourcing period, so these technical risks can be properly managed and the cost of outsourcing project can be further reduced. The main purpose of this paper is to identify the different phases of IS outsourcing life cycle, and to discuss the implications of success and risk factors, software quality and project management,and their impacts to the success of IT outsourcing.

Most outsourcing initiatives involve strategic planning and management participation, therefore, the decision process is obviously broad and lengthy. In order to conduct a comprehensive study onto outsourcing project risk analysis, we propose an IS outsourcing life cycle framework to be served as a yardstick. Each IS outsourcing phase is named and all inherited risks are identified in this life cycle framework.Furthermore,we propose to use software qualitymanagement tools and methods in order to enhance the success rate of IS outsourcing project.

ISO 9000 is a series of quality systems standards developed by the International Organization for Standardization (ISO).ISO's quality standards have been adopted by many countries as a major target for quality certification.Other ISO standards such as ISO 9001, ISO 9000-3,ISO 9004-2, and ISO 9004-4 are quality standards that can be applied to the software industry.Currently, ISO is working on ISO 31000, a risk management guidance standard. These ISO quality systems and risk management standards are generic in nature, however, they may not be sufficient for IS outsourcing practice. This paper, therefore,proposes an outsourcing life cycle framework to distinguish related quality and risk management issues during outsourcing practice.

The following sections start with needed theoretical foundations to IS outsourcing,including economic theories, outsourcing contracting theories, and risk theories. The IS outsourcing life cycle framework is then introduced.It continues to discuss the risk implications in precontract,contract, and post-contract phases. ISO standards on quality systems and risk management are discussed and compared in the next section. A conclusion and direction for future study are provided in the last section.

2. Theoretical foundations

2.1. Economic theories related to outsourcing

Although there are a number of reasons for pursuing IS outsourcing,the cost saving

is a main attraction that leads companies to search for outsourcing opportunities. In principle, five outsourcing related economic theories that lay the groundwork of outsourcing practice, theyare:(1)production cost economics,(2)transaction cost theory,(3)resource based theory,(4)competitive advantage, and(5)economies of scale.

Production cost economics was proposed by Williamson, who mentioned that “a firm seeks to maximize its profit also subjects to its production function and market opportunities for selling outputs and buying inputs”. It is clear that production cost economics identifies the phenomenon that a firm may pursue the goal of low-cost production process.

Transaction cost theory was proposed by Coase. Transaction cost theory implies that in an economy, there are many economic activities occurred outside the price systems. Transaction costs in business activities are the time and expense of negotiation, and writing and enforcing contracts between buyers and suppliers .When transaction cost is low because of lower uncertainty, companies are expected to adopt outsourcing.

The focus of resource-based theory is “the heart of the firm centers on deployment and combination of specific inputs rather than on avoidance of opportunities”. Conner suggested that “Firms as seekers of costly-to-copy inputs for production and distribution”.Through resource-based theory, we can infer that “outsourcing decision is to seek external resources or capability for meeting firm's objectives such as cost-saving and capability improving”.

Porter, in his competitive forces model, proposed the concept of competitive advantage. Besanko et al.explicated the term of competitive advantage, through economic concept, as “When a firm(or business unit within a multi-business firm) earns a higher rate of economic profit than the average rate of economic profit of other firms competing within the same market, the firm has a competitive advantage.” Outsourcing decision, therefore, is to seek cost saving that meets the goal of competitive advantage within a firm.

The economies of scale is a theoretical foundation for creating and sustaining the consulting business. Information systems(IS) and information technology(IT) consulting firms, in essence, bear the advantage of economies of scale since their average costs decrease because they offer a mass amount of specialized IS/IT services in the marketplace.

2.2. Economic implication on contracting

An outsourcing contract defines the provision of services and charges that need to be completed in a contracting period between two contracting parties. Since most IS/IT projects are large in scale, a valuable contract should list complete set of tasks and responsibilities that each contracting party needs to perform. The study of contracting becomes essential because a complete contract setting could eliminate possible opportunistic behavior, confusion, and ambiguity between two contracting parties.

Although contracting parties intend to reach a complete contract,in real world, most contracts are incomplete. Incomplete contracts cause not only implementing difficulties

but also resulting in litigation action. Business relationship may easily be ruined by holding incomplete contracts. In order to reach a complete contract, the contracting parties must pay sufficient attention to remove any ambiguity, confusion, and unidentified and immeasurable conditions/ terms from the contract. According to Besanko et al., incomplete contracting stems from the following three factors: bounded rationality, difficulties on specifying or measuring performance, and asymmetric information.

Bounded rationality describes human limitation on information processing, complexity handling, and rational decision-making. An incomplete contract stems from unexpected circumstances that may be ignored during contract negotiation. Most contracts consist of complex product requirements and performance measurements. In reality, it is difficult to specify a set of comprehensive metrics for meeting each party's right and responsibility. Therefore, any vague or open-ended statements in contract will definitely result in an incomplete contract. Lastly, it is possible that each party may not have equal access to all contract-relevant information sources. This situation of asymmetric information results in an unfair negotiation,thus it becomes an incomplete contract.

2.3. Risk in outsource contracting

Risk can be identified as an undesirable event, a probability function,variance of the distribution of outcomes, or expected loss. Risk can be classified into endogenous and exogenous ris ks. Exogenous risks are“risks over which we have no control and which are not affected by our actions.”. For example, natural disasters such as earthquakes and flood are exogenous risks. Endogenous risks are “risks that are dependent on our actions”.We can infer that risks occurring during outsource contracting should belong to such category.

Risk (RE) can be calculated through “a function of the probability of a negative outcome and the importance of the loss due to the occurrence of this outcome:

RE = ΣiP(UOi)≠L(UOi) (1) where P(UOi) is the probability of an undesirable outcome i, and L(UOi) is the loss due to the undesirable outcome i.”.

Software risks can also be analyzed through two characteristics :uncertainty and loss. Pressman suggested that the best way to analyze software risks is to quantify the level of uncertainty and the degree of loss that associated with each kind of risk. His risk content matches to above mentioned Eq.(1).Pressman classified software risks into the following categories: project risks, technical risks, and business risks.

Outsourcing risks stem from various sources. Aubert et al. adopted transaction cost theory and agency theory as the foundation for deriving undesirable events and their associated risk factors.Transaction cost theory has been discussed in the Section 2.2. Agency theory focuses on client's problem while choosing an agent(that is, a service provider), and working relationship building and maintenance, under the restriction of information asymmetry.Various risk factors would be produced if such agent–client relationship becomes crumble.

It is evident that a complete contract could eliminate the risk that caused by an incomplete contract and/or possible opportunistic behavior prompted by any contracting party. Opportunistic behavior is one of the main sources that cause transactional risk. Opportunistic behavior occurs when a transactional partner observes away of saving cost or removing responsibility during contracting period, this company may take action to pursue such opportunity. This type of opportunistic behavior could be encouraged if such contract was not completely specified at the first place.

Outsourcing risks could generate additional unexpected cost to an outsourcing project. In order to conduct a better IS outsourcing project, identifying possible risk factors and implementing matured risk management process could make information systems outsourcing more successful than ever.

https://www.sodocs.net/doc/d31458401.html,rmation system outsourcing life cycle

The life cycle concept is originally used to describe a period of one generation of organism in biological system. In essence, the term of life cycle is the description of all activities that a subject is involved in a period from its birth to its end. The life cycle concept has been applied into project management area. A project life cycle, according to Schwalbe, is a collection of project phases such as concept,development, implementation, and close-out. Within the above mentioned four phases, the first two phases center on “planning”activity and the last two phases focus on “delivery the actual work” Of project management.

Similarly, the concept of life cycle can be applied into information systems outsourcing analysis. Information systems outsourcing life cycle describes a sequence of activities to be performed during company's IS outsourcing practice. Hirsch heim and Dibbern once described a client-based IS outsourcing life cycle as: “It starts with the IS outsourcing decision, continues with the outsourcing relationship(life of the contract)and ends with the cancellation or end of the relationship, i.e., the end of the contract. The end of the relationship forces a new outsourcing decision.” It is clear that Hirsch heim and Dibbern viewed “outsourcing relationship” as a determinant in IS outsourcing life cycle.

IS outsourcing life cycle starts with outsourcing need and then ends with contract completion. This life cycle restarts with the search for a new outsourcing contract if needed. An outsourcing company may be satisfied with the same outsourcing vendor if the transaction costs remain low, then a new cycle goes on. Otherwise, a new search for an outsourcing vendor may be started. One of the main goals for seeking outsourcing contract is cost minimization. Transaction cost theory(discussed in the Section 2.1)indicates that company pursuing contract costs money, thus low transaction cost will be the driver of extending IS outsourcing life cycle.

The span of IS outsourcing life cycle embraces a major portion of contracting activities. The whole IS outsourcing life cycle can be divided into three phases(see Fig.1): pre-contract phase, contract phase, and post-contract phase. Pre-contract phase includes activities before a major contract is signed, such as identifying the need for outsourcing, planning and strategic setting, and outsourcing vendor selection. Contract phase starts

while an outsourcing contract is signed and then lasted until the end of contracting period. It includes activities such as contracting process, transitioning process, and outsourcing project execution. Post-contract phase contains those activities to be done after contract expiration, such as outsourcing project assessment, and making decision for the next outsourcing contract.

Fig.1. The IS outsourcing life cycle

When a company intends to outsource its information systems projects to external entities, several activities are involved in information systems outsourcing life cycle. Specifically, they are:

1. Identifying the need for outsourcing:

A firm may face strict external environment such as stern market competition,

competitor's cost saving through outsourcing, or economic downturn that initiates it to consider outsourcing IS projects. In addition to external environment, some internal factors may also lead to outsourcing consideration. These organizational predicaments include the need for technical skills, financial constraint, investors' request, or simply cost saving concern. A firm needs to carefully conduct a study to its internal and external positioning before making an outsourcing decision.

2. Planning and strategic setting:

If a firm identifies a need for IS outsourcing, it needs to make sure that the decision to outsource should meet with company's strategic plan and objectives. Later, this firm needs to integrate outsourcing plan into corporate strategy. Many tasks need to be fulfilled during planning and strategic setting stages, including determining outsourcing goals, objectives, scope, schedule, cost, business model, and processes. A careful outsourcing planning prepares a firm for pursuing a successful outsourcing project.

3. Outsourcing vendor selection:

A firm begins the vendor selection process with the creation of request for information (RFI) and request for proposal (RFP) documents. An outsourcing firm should provide sufficient information about the requirements and expectations for an outsourcing project. After receiving those proposals from vendors, this company needs to select a prospective outsourcing vendor, based on the strategic needs and project requirements.

4. Contracting process:

A contract negotiation process begins after the company selects a probable outsourcing vendor. Contracting process is critical to the success of an outsourcing project since all the aspects of the contract should be specified and covered, including fundamental, managerial, technological, pricing, financial, and legal features. In order to avoid resulting in an incomplete contract, the final contract should be reviewed by two parties' legal consultants.Most importantly, the service level agreements (SLA) must be clearly identified in the contract.

5. Transitioning process:

Transitioning process starts after a company signed an outsourcing contract with a vendor. Transition management is defined as “the detailed, desk-level knowledge transfer and documentation of all relevant tasks, technologies, workflows, people, and functions”.Transitioni ng process is a complicate phase in IS outsourcing life cycle since it involves many essential workloads before an outsourcing project can be actually implemented. Robinson et al.characterized transition management into the following components:“employee management, communication management, knowledge management, and quality management”. It is apparent that conducting transitioning process needs the capabilities of human resources, communication skill, knowledge transfer, and quality control.

6. Outsourcing project execution:

After transitioning process, it is time for vendor and client to execute their outsourcing project. There are four components within this“contract governance” stage:

project management, relationship management, change management, and risk management. Any items listed in the contract and its service level agreements (SLAs) need to be delivered and implemented as requested. Especially, client and vendor relationships, change requests and records, and risk variables must be carefully managed and administered.

7. Outsourcing project assessment:

During the end of an outsourcing project period, vendor must deliver its final product/service for client's approval. The outsourcing client must assess the quality of product/service that provided by its client. The outsourcing client must measure his/her satisfaction level to the product/service provided by the client. A satisfied assessment and good relationship will guarantee the continuation of the next outsourcing contract.

The results of the previous activity (that is, project assessment) will be the base of determining the next outsourcing contract. A firm evaluates its satisfaction level based on predetermined outsourcing goals and contracting criteria. An outsourcing company also observes outsourcing cost and risks involved in the project. If a firm is satisfied with the current outsourcing vendor, it is likely that a renewable contract could start with the same vendor. Otherwise, a new “precontract phase” would restart to s earch for a new outsourcing vendor.This activity will lead to a new outsourcing life cycle. Fig.1 shows two dotted arrowlines for these two alternatives: the dotted arrow line 3.a.indicates “renewable contract” path and the dotted arrow line 3.b.indicates “a new contract search” path.

Each phase in IS outsourcing life cycle is full of needed activities and processes (see Fig.1). In order to clearly examine the dynamics of risks and outsourcing activities, the following sections provide detailed analyses. The pre-contract phase in IS outsourcing life cycle focuses on the awareness of outsourcing success factors and related risk factors. The contract phase in IS outsourcing life cycle centers on the mechanism of project management and risk management. The post-contract phase in IS outsourcing life cycle concentrates on the need of selecting suitable project quality assessment methods.

4. Actions in pre-contract phase: awareness of success and risk factors

The pre-contract period is the first phase in information systems outsourcing life cycle (see Fig.1). While in this phase, an outsourcing firm should first identify its need for IS outsourcing. After determining the need for IS outsourcing, the firm needs to carefully create an outsourcing plan. This firm must align corporate strategy into its outsourcing plan.

In order to well prepare for corporate IS outsourcing, a firm must understand current market situation, its competitiveness, and economic environment. The next important task to be done is to identify outsourcing success factors, which can be used to serve as the guidance for strategic outsourcing planning. In addition to know success factors,an outsourcing firm must also recognize possible risks involved in IS outsourcing, thus allows a firm to formulate a better outsourcing strategy.

Conclusion and research directions

This paper presents a three-phased IS outsourcing life cycle and its associated risk factors that affect the success of outsourcing projects.Outsourcing life cycle is complicated and complex in nature. Outsourcing companies usually invest a great effort to select suitable service vendors However,many risks exit in vendor selection process. Although outsourcing costs are the major reason for doing outsourcing, the firms are seeking outsourcing success through quality assurance and risk control. This decision path is understandable since the outcome of project risks represents the amount of additional project cost. Therefore, carefully manage the project and its risk factors would save outsourcing companies a tremendous amount of money.

This paper discusses various issues related to outsourcing success, risk factors, quality assessment methods, and project management techniques. The future research may touch alternate risk estimation methodology. For example, risk uncertainty can be used to identify the accuracy of the outsourcing risk estimation. Another possible method to estimate outsourcing risk is through the Total Cost of Ownership(TCO) method. TCO method has been used in IT management for financial portfolio analysis and investment decision making. Since the concept of risk is in essence the cost (of loss) to outsourcing clients, it thus becomes a possible research method to solve outsourcing decision.

信息系统的生命周期和风险分析

1.绪言

信息系统外包在信息技术工业已经获得了巨大的关注。虽然有许多原因让公司推行信息系统（IS）外包，文献中显示IS外包最突出的动机是“节约成本”，成本因素是外包的一个重要的决定因素。

除了成本因素，还有其他一些原因决定了外包。外包研究所1998年从他们的成员中调查了外包最终用户，发现了公司外包的前十个原因：

减少和控制经营成本,改善公司的重点，获得世界一流的能力,将免费的内部资源用于其他目的，使用国内无法得到的资源，获得加速重组的好处，功能难以管理/失去控制，使资本资金可用，分担风险，和现金注入。

在这些外包的十大原因中，有三个涉及财务关注的项目，他们是经营成本，可获得的资本资金，和现金注入。由于在外包的国家中存在工资差别现象，显而易见的是，外包公司将节省大量的劳动力成本。根据Gartner公司的报告，世界商业外包服务在2002年到2007年，将从增长一千百点零亿美元到增长一千七百三十点零亿美元，近9.5％的年增长率。

除了关注节省成本，还有决定外包的其他影响因素，其中包括成功的意识和风险因素，外包的风险识别和管理，项目质量管理。外包活动基本上是复杂的并且外包项目通常带有一个巨大的风险。非托管外包的风险会增加项目总成本，贬值软件的质量，拖延项目的完工时间，最后还有成功率较低的外包项目。外包的风险在某些领域已经发现，如意外转型和管理费用，转换成本，昂贵的合同修正案，争端和诉讼，服务贬低，费用上涨的损失，组织能力，隐藏的服务费用，等等。

大多数关于外包的出版研究侧重于组织和管理问题。我们认为IS外包项目包括各种风险和不确定性，可能会抑制外包成功的机会。除了服务和管理有关的风险问题，我们认为，制约外包成功程度的技术问题可能已被忽视。这些技术问题是项目管理，软件质量，和可以用来推行IS外包项目的质量评估方法。非托管风险产生损失。我们打算在外包期间辨认技术风险，所以这些技术风险能够得到适当的管理并且外包项目的成本效益可以进一步降低。本文的主要目的确定IS外包的生命周期的不同阶段，并且讨论成功的影响和风险因素，软件的质量和项目管理，和它们对IT 外包成功的影响。

大多数外包举措涉及战略规划和管理，因此，决定的过程显然是广泛的和漫长的。为了在外包项目风险分析上进行全面的研究，我们提议将IS外包生命周期框架

PLC控制下的电梯系统外文文献翻译、中英文翻译、外文翻译

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中英文参考文献格式

中文参考文献格式 参考文献（即引文出处）的类型以单字母方式标识： M——专著，C——论文集，N——报纸文章，J——期刊文章，D——学位论文，R——报告，S——标准，P——专利；对于不属于上述的文献类型，采用字母“Z”标识。 参考文献一律置于文末。其格式为： （一）专著 示例 [1] 张志建.严复思想研究[M]. 桂林：广西师范大学出版社，1989. [2] 马克思恩格斯全集：第1卷[M]. 北京：人民出版社，1956. [3] [英]蔼理士.性心理学[M]. 潘光旦译注.北京：商务印书馆，1997. （二）论文集 示例 [1] 伍蠡甫.西方文论选[C]. 上海：上海译文出版社，1979. [2] 别林斯基.论俄国中篇小说和果戈里君的中篇小说[A]. 伍蠡甫.西方文论选：下册[C]. 上海：上海译文出版社，1979. 凡引专著的页码，加圆括号置于文中序号之后。 （三）报纸文章 示例 [1] 李大伦.经济全球化的重要性[N]. 光明日报，1998-12-27，（3） （四）期刊文章 示例 [1] 郭英德.元明文学史观散论[J]. 北京师范大学学报（社会科学版），1995（3）. （五）学位论文 示例 [1] 刘伟.汉字不同视觉识别方式的理论和实证研究[D]. 北京：北京师范大学心理系，1998. （六）报告 示例 [1] 白秀水，刘敢，任保平. 西安金融、人才、技术三大要素市场培育与发展研究[R]. 西安：陕西师范大学西北经济发展研究中心，1998. （七）、对论文正文中某一特定内容的进一步解释或补充说明性的注释，置于本页地脚，前面用圈码标识。 参考文献的类型 根据GB3469-83《文献类型与文献载体代码》规定，以单字母标识： M——专著（含古籍中的史、志论著） C——论文集 N——报纸文章 J——期刊文章 D——学位论文 R——研究报告 S——标准 P——专利 A——专著、论文集中的析出文献 Z——其他未说明的文献类型 电子文献类型以双字母作为标识： DB——数据库 CP——计算机程序 EB——电子公告

电子信息工程专业课程翻译中英文对照表

电子信息工程专业课程名称中英文翻译对照 （2009级培养计划）

实践环节翻译

高等数学Advanced Mathematics 大学物理College Physics 线性代数Linear Algebra 复变函数与积分变换Functions of Complex Variable and Integral Transforms 概率论与随机过程Probability and Random Process 物理实验Experiments of College Physics 数理方程Equations of Mathematical Physics 电子信息工程概论Introduction to Electronic and Information Engineering 计算机应用基础Fundamentals of Computer Application 电路原理Principles of Circuit 模拟电子技术基础Fundamentals of Analog Electronics 数字电子技术基础Fundamentals of Digital Electronics C语言程序设计The C Programming Language 信息论基础Fundamentals of Information Theory 信号与线性系统Signals and Linear Systems 微机原理与接口技术Microcomputer Principles and Interface Technology 马克思主义基本原理Fundamentals of Marxism 毛泽东思想、邓小平理论 和“三个代表”重要思想 概论 Thoughts of Mao and Deng 中国近现代史纲要Modern Chinese History 思想道德修养与法律基 础 Moral Education & Law Basis 形势与政策Situation and Policy 英语College English 体育Physical Education 当代世界经济与政治Modern Global Economy and Politics 卫生健康教育Health Education 心理健康知识讲座Psychological Health Knowledge Lecture 公共艺术课程Public Arts 文献检索Literature Retrieval 军事理论Military Theory 普通话语音常识及训练Mandarin Knowledge and Training 大学生职业生涯策划 （就业指导） Career Planning (Guidance of Employment ) 专题学术讲座Optional Course Lecture 科技文献写作Sci-tech Document Writing 高频电子线路High-Frequency Electronic Circuits 通信原理Communications Theory 数字信号处理Digital Signal Processing 计算机网络Computer Networks 电磁场与微波技术Electromagnetic Field and Microwave

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均是精品，欢迎下载学习！！！ 电力电子技术的发展及应用 朱磊1侯振义1张开2 （空军工程大学电讯工程学院陕西西安710077） （南京理工大学动力工程学院江苏南京210000） 摘要：本文通过介绍电力电子技术的发展及应用，阐述了电力电子技术在国民经济中的重要作用，结合国家政策，描绘出我国电力电子行业的大好前景。 关键词：电力电子技术功率器件逆变能源 电力电子技术，又称功率电子技术。它主要研究各种电力电子器件，以及这些电力电子器件所构成的各种各样高效地完成对电能的变换和控制的电路或装置。它既是电子学在强电（高电压、大电流）或电工领域的一个分支，又是电工学在弱电（低电压、大电流）或电子领域的一个分支，总之是强弱电相结合的新学科。 1 电力电子技术的发展 电力电子技术的发展与功率器件的发展密切相关，1948年普通晶体管的发明引起了电子工业革命，1957年第一只晶闸管的问世，为电力电子技术的诞生奠定了基础。 1.1 电力电子技术的晶闸管时代 由于大功率硅整流器能够高效率的把工频交流电转变为直流电，因此在60年代和70年代，大功率硅整流管和晶闸管的开发与应用得到大发展，这一时期称之为电力电子技术的晶闸管时代。 1.2 电力电子技术的逆变时代 20世纪70年代，随着自关断器件的出现，电力电子技术进入了逆变时代。七十年代出现了世界范围的能源危机，交流电机变频调速因节能效果显著而迅速发展。在70年代到80年代，随着变频调速装置的普及，大功率逆变用的晶闸管、巨型功率晶体管(GTR)和门极可关断晶闸管(GT0)成为当时电力电子器件的主角。这时的电力电子技术已经能够实现整流和逆变，但工作频率较低，仅局限在中低频范围内。 1.3现代电力电子时代 80年代末期和90年代初期发展起来的以功率MOSFET和IGBT为代表的集高频、高压和大电流于一身的功率半导体复合器件，使以低频技术处理问题为主的传统电力电子学，向以高频技术处理问题为主的现代电力电子学转变创造了条件，表明传统电力电子技术已经进入现代电力电子时代。 这一时期，各种新型器件应用大规模集成电路技术，向复合化、模块化的方向发展，使得器件及结构紧凑、体积缩小，并且能够综合了不同器件的优点。在性能上，器件的容量不断增大，工作频率不断提高，目前，市场化的碳化硅器件达(3500V\1200A),智能功率模块达到(1200V\800A),在斩波器的PWM开关频率可达1MHz。 这一时期，各种新的控制方法得到了广泛应用，特别是现代电力电子技术越来越多地运用了人工智能技术。在所有人工智能学科中，神经网络将对电力电子学产生的影响最大，利用混合人工智能技术(神经一模糊，神经一遗传，神经一模糊一遗传，模糊一遗传)开发强大的智能控制以及估计方法，单个神经模糊专用集成芯片能承担无传感器矢量控制，且具有在线故障诊断和容错控制能力。基于人工智能的模糊控制在参数变化和负载转矩扰动的非线性反馈系统中可能可以提供最好的鲁棒性，在故障监测和故障耐力控制中将会起到越来越重要的作用。 2电力电子的技术应用 随着科技的不断发展和人们要求的不断提高，电力电子技术的应用越来越广泛。当今世界先进工业国家正处于由“工业经济”模式向“信息经济”模式转变的时期。电力电子技术作为信息产业与传统产业之间的桥梁，是在非常广泛的领域内改造传统产业、支持高新技术发展的基础。因此，电力电子技术将在国民经济中扮演着越来越重要的角色。

英文引用及参考文献格式要求

英文引用及参考文献格式要求 一、参考文献的类型 参考文献（即引文出处）的类型以单字母方式标识，具体如下： M——专著C——论文集N——报纸文章 J——期刊文章D——学位论文R——报告 对于不属于上述的文献类型，采用字母“Z”标识。 对于英文参考文献，还应注意以下两点： ①作者姓名采用“姓在前名在后”原则，具体格式是：姓，名字的首字母.如：MalcolmRichardCowley应为：Cowley,M.R.，如果有两位作者，第一位作者方式不变，&之后第二位作者名字的首字母放在前面，姓放在后面，如：FrankNorris与IrvingGordon应为：Norris,F.&I.Gordon.； ②书名、报刊名使用斜体字，如：MasteringEnglishLiterature，EnglishWeekly。 二、参考文献的格式及举例 1.期刊类 【格式】[序号]作者.篇名[J].刊名，出版年份，卷号（期号）：起止页码. 【举例】 [1]王海粟.浅议会计信息披露模式[J].财政研究，2004,21(1)：56-58. [2]夏鲁惠.高等学校毕业论文教学情况调研报告[J].高等理科教育，2004(1):46-52. [3]Heider,E.R.&D.C.Oliver.Thestructureofcolorspaceinnamingandmemo ryoftwolanguages[J].ForeignLanguageTeachingandResearch,1999,(3):62–6 7. 2.专著类 【格式】[序号]作者.书名[M].出版地：出版社，出版年份：起止页码. 【举例】[4]葛家澍，林志军.现代西方财务会计理论[M].厦门：厦门大学出版社，2001：42. [5]Gill,R.MasteringEnglishLiterature[M].London:Macmillan,1985:42-45. 3.报纸类 【格式】[序号]作者.篇名[N].报纸名，出版日期（版次）. 【举例】 [6]李大伦.经济全球化的重要性[N].光明日报，1998-12-27(3). [7]French,W.BetweenSilences:AVoicefromChina[N].AtlanticWeekly,198 715(33). 4.论文集 【格式】[序号]作者.篇名[C].出版地：出版者，出版年份：起始页码. 【举例】 [8]伍蠡甫.西方文论选[C].上海：上海译文出版社，1979：12-17. [9]Spivak,G.“CantheSubalternSpeak?”[A].InC.Nelson&L.Grossberg(e ds.).VictoryinLimbo:Imigism[C].Urbana:UniversityofIllinoisPress,1988, pp.271-313.

管理信息系统外文翻译

管理信息系统外文翻译-标准化文件发布号：（9456-EUATWK-MWUB-WUNN-INNUL-DDQTY-KII

英文文献翻译 二〇年月日

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电力电子技术外文翻译

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考。晶闸管必须保持在反向电压，只有在这个时间，设备才有能力阻止它不是处于正向电压导通状态。 如果一个正向电压应用于晶闸管的这段时间已过，设备可能因为过早地启动并有可能导致设备和电路损害。数据表指定晶闸管通过的反向电压在这段期间和超出这段时间外的一个指定的电压上升率。这段期间有时被称为晶闸管整流电路的周期。 根据使用要求，各种类型的晶闸管是可得到的。在除了电压和电流的额定率，转弯时间，和前方的电压降以及其他必须考虑的特性包括电流导通的上升率和在关闭状态的下降率。 1。控制晶闸管阶段。有时称为晶闸管转换器，这些都是用来要是整顿阶段，如为直流和交流电机驱动器和高压直流输电线路应用的电压和电流的驱动。主要设备要求是在大电压、电流导通状态或低通态压降中。这类型的晶闸管的生产晶圆直径到10厘米，其中平均电流目前大约是4000A，阻断电压为5之7KV。 2。逆变级的晶闸管。这些设计有小关断时间，除了低导通状态电压，虽然在设备导通状态电压值较小，可设定为2500V和1500A。他们的关断时间通常在几微秒范围到100μs之间，取决于其阻断电压的速率和通态压降。 3。光控晶闸管。这些会被一束脉冲光纤触发使其被引导到一个特殊的敏感的晶闸管地区。光化的晶闸管触发，是使用在适当波长的光的对硅产生多余的电子空穴。这些晶闸管的主要用途是应用在高电压，如高压直流系统，有许多晶闸管被应用在转换器阀门上。光控晶闸管已经发现的等级，有4kV的3kA，导通状态电压2V、光触发5毫瓦的功率要求。 还有其它一些晶闸管，如辅助型关断晶闸管（关贸总协定），这些晶闸管其他变化，不对称硅可控（ASCR）和反向进行，晶闸管（RCT）的。这些都是应用。 B部分 功率集成电路 功率集成电路的种类 现代半导体功率控制相当数量的电路驱动，除了电路功率器件本身。这些控制电路通常由微处理器控制，其中包括逻辑电路。这种在同一芯片上包含或作

电子信息工程本科毕业中英文翻译

英语原文： Life of LED-Based White Light Sources The interest for using light-emitting diodes (LEDs) for display and illumination applications has been growing steadily over the past few years. The potential for long life and reduced energy use are two key attributes of this rapidly evolving technology that have generated so much interest for its use in the above mentioned applications. Traditionally, the lamp life of light sources commonly used in illumination applications is determined by subjecting them to a predetermined on/off cycle until half the number of light sources cease to produce light. Unlike these sources, LEDs rarely fail catastrophically; instead, their light output slowly degrades over time. Even if an LED is technically operating and producing light, at some point the amount of light produced by the LED will be insufficient for the intended application. Therefore, the life of an LED should be based on the amount of time that the device can produce sufficient light for the intended application,rather than complete failure. Based on this argument, a recent publication from an industry group defines the life of an LED device or system for use in general lighting applications as the operating time, in hours, for the light output to reach 70% of its initial value. The most widely used white LEDs incorporate a layer of phosphor over a GaN-based, short-wavelength light emitter. Usually, the phosphor is embedded inside an epoxy resin that surrounds the LED die. Some portion of the short-wavelength radiation emitted by the LED is down-converted by the phosphor, and the combined radiation creates white light.Early white LEDs were packaged similar to the indicator-style colored LEDs, specifically 5 mm and SMD (surface mount devices). Although these products demonstrated the concept of a white light source, they did not produce sufficient light for display and illumination applications. Furthermore, these indicator-style white LEDs had a relatively short life, 5000–10 000h to reach 70% light level under normal operating conditions. To address the higher luminous flux requirements, manufacturers have started to commercialize high-power illuminator LEDs that are presently producing over one hundred times the flux compared to indicator-style white LEDs. The higher light output is