干货!SCI论文引言写作

　当你上课感觉就像打酱油时，当你对研究生很迷茫时，当你坐在电脑前孜孜不倦时，请看下面的文章，很受用，至少我心里现在没有以前浮躁。好的文章有时能改变一个人的精神状态，下面就是其中之一。

　 引言又称前言或绪论，属 SCI 论文的开场白，属引导读者进入论文的主题，让读者有心理准备，有总揽论文全局的重要性，是论文中非常难写的部分之一。

　 1. 内容与结构

　 引言在内容上，通常包括背景、目的、主要研究成果及与前人工作的关系等，研究热点、存在问题及所做工作的意义。引言在结构上，通常先介绍范围较宽泛的一般性事实，需要文献回顾，说明研究工作与过去工作的关系，对研究情况作横向比较，写明前人在本课题相关领域所做的工作及存在的空白或不足。然后将重点逐渐转入与论文所探讨的问题有密切联系的主题，指出有某个问题或现象仍值得进一步研究，进而将焦点转到要探讨的研究问题上。最后阐述研究目的，将作者的研究任务具体化，还可根据情况说明作者在已有工作基础上的贡献或创新。对篇幅较长、结构复杂的论文，其引言的结尾部分还应有论文构架或层次标题的简略说明。

　 2. 写作原则

　 引言写作基本要求是：内容全面，逐次展开；开门见山，不绕圈子；言简意赅，突出重点；尊重科学，实事求是。

　引言写作有以下原则：

　 （1）按引言写作要求和内容逐渐展开，不要将引言写成摘要的注释，不要重复摘要的内容，也不要在引言中展开讨论。

　 （2）视论文类别及研究领域来确定文献综述的长度（通常至少需要一两个段落），如果研究主题为许多其他学者曾经探讨的问题，则应该引用、讨论较多的文献；相反如果作者只是讨论别人最近才提出的问题，则可能引用、讨论少量的文献即可。

　 特别注意

　 学术论文通常需要在引言部分较详细进行文献综述，以清楚交待研究现状，引言的段落可能较多。学位论文的引言可单独写成一章，并用足够的文字详细叙述，以反映作者掌握了坚实的理论基础和系统的专门知识，具有开阔的科研视野，对研究方案做了充分论证，有必要详细回顾有关历史、综述前人工作以及进行理论分析等。

　 SCI 论文是面向国际读者的，作者应站在国际读者的角度来写，因此at home and abroad 和domestic 之类的表达在这种语境中出现不大妥当。

　 （3）要区分所指出的“存在的问题”的类别，并采用相应的叙述方法。一般来说主要有以下类别：

　 1 以前的学者尚未研究或处理不够完善的重要课题；

　 2 过去的研究衍生出的有待探讨的新问题；

　3 以前的学者曾经提出的互不相容而且需要进一步研究才能解决的问题；

　 4 可以扩充到新的题目或领域中的过去的研究成果；

　 5 可以扩展到新的应用范围内的以前提出的方法或技术。

　 （4）要慎重而有保留地叙述前人工作的欠缺及自己的创新之处。可以使用 limited to conditions（限于条件）和 there are few researches in this area（目前研究甚少）等谦虚用语，但不必对自己的研究或能力过谦。不宜用 have little talent and less learning（才疏学浅），limited to author’s level（水平有限），beg for your advice（恳求指教）和 throw away a brick in order to get a gem（抛砖引玉）等客套用语；也不要自吹自擂，抬高自己，贬低别人，除非是事实，一般不用 discovers…for the first time 或 presents…for the first time（首次发现、提出），has(have) very high academic value（有很高的学术价值），fill the gaps at home and abroad（填补了国内外空白），reach(es) international advanced level（达到国际先进水平）等评价式用语。

　 （5）要繁简适度地阐述研究背景，对所探讨问题的本质和范围的阐述要准确、简洁、清楚，内容选择不必过于分散、琐碎，措词要精练。复述潜在读者早已明白的教科书中的一般性知识不仅没有必要，而且容易使人厌烦，但如果对必要信息的叙述过于简略，则容易使读者感到突兀。

　（6）要引用最相关的文献，优先引用研究的经典、重要和最具说服力的文献，力戒刻意回避引用最重要的相关文献，甚至是对作者研究工作具有某种重要“启示”性意义的文献，也不要不恰当地大量引用作者本人的文献。

　 （7）要采取适当的方式强调作者在本次研究中的重要发现或贡献，让读者顺着逻辑的演进阅读全文，不要故意制造悬念。

　 （8）要使用规范的名词、名称、术语和缩略语，不要随意使用非公知公用的术语和缩略语。非公知公用的术语和缩略语首次出现时应对其给予解释或定义，以帮助阅读与理解。

　 （9）要适当地使用 We 或 The author 之类的词语，明确指出作者所做的工作，以避免难以区分别人和作者所做工作或引起误解。

　 3. 示例分析

　 2. 悬垂不定式

　 2. 悬垂不定式

　 下面列举一个引言示例，为了表述方便，后面还附上了所引用的参考文献。

　 【1】

　 1. Introduction

　 This paperaims to estimate the residual torque of torsion bar with circular cross sectionunder the predetermined torsion angle for a given period. Generally，such a physical experimentis impossible

　of achievement due to the long period of given time. Therefore，a method combiningdamage mechanics theory and experiment is proposed for solving this problem.

　 Firstly，based on the damagemechanics，establishthe functional relationships between torque and time in terms of twist angleand material constant，that is，the theoretical curveof torque versus time and the threshold relational expression between torqueand torsion shear stress. This expression indicates that，for some givenmaterials，the biggerthe twist angle provides，the fasterthe attenuation rate of torque with the course of time is.

　 Then，to shorten the periodof the experiment and research，anaccelerating experiment scheme is proposed based on the above theoreticalanalysis. A torsion experiment is performed in the case of large twist angle(far more than the predetermined torsion angle) to determinethe torque threshold. After that，the torsionshear strain threshold is determined according to damage mechanics.

　 Finally，torque threshold undersmall twist angle is inferred indirectly from the shear strain thresholdobtained under large twist angle on basis of damage mechanics.

　 However，it should be noted that the initialmaximum shear stress is close to the yield shear stress of the material underconditions of small twist angle. As a consequence，the bar

　must be in the elastic-plastic state of the material under largetwist angle. Thus，the experiment and theoreticalresearch on traditional solid mechanics and damage mechanics must be carriedout in the elastic-plastic zone of the material.

　 ［1］Zhang Xing，Zhao Jun. Applied fatigue damage mechanics ofmetal components ［M］. Beijing：National Defence Industry Press，1998. (in Chinese)

　 ［2］Zhang Xing，Zhao Jun，Huang Kezhi. A method of damage mechanics for the predictionof fatigue life［J］. KeyEngineering Materials，1998，145−149：433−442.

　 ［3］Zhang Xing，Zhao Jun，Zheng Xudong. Methodof damage mechanics for prediction of structure member fatigue lives［C／CD］//Handbook ofFatigue Crack Propagation in Metallic Structures. CARPINTERI Andrea，editor，Vol. I，ElsevierScience B. V.，Amsterdam，the Netherlands，1994.

　 ［4］Lemaitre J. A course on damage mechanics［M］. New York：Springer-Verlag，1992.

　 此例中，第 1 段主要指出研究目的；2～4 段主要以“指示性摘要”的形式叙述研究过程或内容；最后一段给出研究结果或结论。写作上存在的主要问题有：没有阐述研究背景；没有明确指出目前（写作当时）相关研究存在的问题；写了研究过程（可能与摘要中的内容重复）；

　没有明确指出作者研究的创新点或独到之处；没有标引文献，而且所引文献不具有代表性（数量、种类少，发表时间早，近年文献未引），不足以反映研究现状。

　 【2】

　 1. Introduction

　 Virtualmanufacturing cell(VMC) is first proposed by C. R. McLean，et al. on the basis of the extension of the traditionalmanufacturing cell in 1982. The main idea is generating manufacturing cell bychoosing appropriate resources from the shared resources database when theproduction task changes[1−2]. Thiscell is a whole or fragment entity extracted from the existing physicalresources without changing the physical layout of the original resources，and is only a kind of resources reconfiguration inlogic. A formation method of VMC is proposed in this paper based on machinepattern and set theory under the following assumptions：(1)Reconfigurableobjects are set of manufacturing resources which are composed of equipment withfixed physical locations；(2)Production task is a process of dynamic change；(3)A productiontask，such as product type，process route and the amount of the product，etc.，is fixed；(4)A workpiececan“visit” the same machine repeatedly at varioustimes of the production

　process；(5)Workpiece is conveyed by AGV；(6)The internalcause of reconfiguration is not covered.

　 此例中，首先介绍 VMC（虚拟制造单元）的概念首次由何人在何时提出，并引用两篇文献，然后阐述 VMC 的含义，最后指出作者在本文中给出的 VMC 生成方法。此引言存在未交代研究背景、引用文献太少、没有指出作者研究的意义等问题，写作上不完整、不规范。以下是修改后的引言：

　 1. Introduction

　 One of the common features of currentmanufacturing systems is the lack of reconfigurability. The change in the marketdemand will create a large number of idle and scraped facilities，resulting in waste of resources and energy. The fundamentalway to solve this problem is the implementation of reconfigurable manufacturingsystem(RMS).Essentially，reconfiguration is to obtain the maximumproduction flexibility by logical or physical configuration changes in wholelife cycle of manufacturing system[1−2].Related researches have been carried out from the developed countries since themid-1990s. However,researchers still don’t have a complete solution of RMS yet. Therefore,it’s of particularimportance to further study the implementing method of it.

　 RMS can be implemented by changing modularcomponents of the reconfigurable machine tool(RMT)，or by moving，replacingor

　adding reconfigurable devices，or by generating a virtual manufacturing cell(VMC)according tological reconfiguration method. At present，thedevelopment of RMT is still in the primary stage，and thereare still difficulties in implementation of RMS by changing the physicalconfiguration of it because the equipment used in current manufacturing systemsare generally conventional equipment and most of them are permanently fixed.However，the physical reconfiguration can be replacedby the logic reconfiguration using VMC. This is because the equipment in VMC isvirtual dynamic entity which can be nonadjacent and fixed at the physicallocation and interconnected in logic and concepts. The interconnection can beimplemented through the path network of logistics systems，such as automated guided vehicle(AGV)，without any need to change the existingphysical layout of the system. As a particular type of manufacturing cell，VMC is usually generated by using group technology. However，the technology suffers from two crucial shortcomings. Oneis completely ignoring the sharing behavior among workpieces as well as cells；the other is the pre-setting of someparameters before the formation of cells. For example，BABU，et al[3] proposed a cellformation algorithm to generate multiple cell configuration based on differentrank order clustering(ROC)，but did not consider the cells sharing in system，

　and moreover some parameters are needed to pre-setsubjectively. SARKER，et al[4] developed a formationmethod of VMC based on process routes and scheduling rather than cell sharing.The method can be used to find the shortest production route in the schedulingsystem involving multiple workpieces and multiple machines. RATCHEV[5]proposed a class-ability formation method of manufacturing cell based on“resourcecell”，which matches up the process requirementwith production capability of manufacturing system dynamically. KO，et al[6−7]presented a formation algorithms of VMC to implement the machine sharing basedon the concept of“machine pattern”. The current researches on manufacturingcell are mainly concentrated on the cell formation and planning，and the practical applications of manufacturing cell onRMS are sparse. In order to implement the logic reconfiguration of RMS，this paper presents the concept of“machine set pattern” based on similarity theory，and the formation method of VMC under some assumptionsis also provided.

　 修改后的引言，增加了对有关文献的引用和综述，清楚地阐明了研究的背景、理由及知识空白，写明了前人的工作以及作者现在所进行的研究内容，在写作上较为完整和规范。

　美辑编译(American Editor)SCI 论文润色服务由以英语为母语，有长

　期编辑论文经验的编辑完成英文论文润色。编辑团队的研究背景涉及临床医学、物理、化学、工程学、材料科学、地球与环境科学、人文社会学、商学等不同学科领域。