1. 研究目的与意义Since foreign language anxiety (FLA) was proposed by Horwitz in 1960s, there is so much research on English learning anxiety both from abroad and at home. Nevertheless, rare studies on foreign language learning anxiety have taken college English majors as subjects (Lin, 2018). Moreover, due to the test-oriented teaching model, English majors may have more anxiety than those of other majors in learning English when they are involved in thoughts about working in an English environment. As a result, further studies on the foreign language learning anxiety of English majors remains a piece of virgin land to be cultivated.In view of such a circumstance, the author intends to search out the current situation of students English learning anxiety of English majors at Nanjing University of Chinese Medicine. Meanwhile, by identifying the distribution of the three sources of English classroom anxiety (communication apprehension, test anxiety, and fear of negative evaluatio

1. 研究目的与意义（文献综述） 1.1研究目的 转杯纺纱技术是一种比较成熟且使用量巨大的纺纱技术。转杯纺纱的质量和产量直接取决于转杯的转速，目前限制转杯转速的主要有轴承和接头技术两个方面。纺纱转杯轴承是支撑高速转杯的关键部件，其支承精度，旋转速度和寿命直接影响纺纱的质量和企业的成本。一般来说，轴承的转速越高，纺纱的质量越好，但转速提升直接影响轴承寿命，所以转杯轴承的寿命研究对于转杯纺纱技术至关重要。 由于影响轴承疲劳寿命的因素多而繁杂，再加上当今国际上使用的轴承寿命理论并不十分统一，有很多需要完善的地方，进行轴承的寿命试验无疑成为评价轴承寿命指标的唯一有效途径。本次设计的主要目的是进行转杯轴承寿命测试实验台的传动链和底座的设计，从而配合加载机构为转杯轴承的寿命测试提�

1. 研究目的与意义 我国是世界上第一大工业生产国，焦化行业、冶炼行业、石油化工行业在生产过程中会产生大量含有多环芳烃（PAHs）、氰化物、氟化物、总石油烃、重金属等污染物的废水、废气、废渣，这些含有有毒有害物质的污染物经沉降、泄露、淋溶会进入焦化厂所在场地及周边地区的土壤中，造成土壤污染，从而对人群造成健康风险。综合已有的研究资料得出，化工行业主要场地土壤污染物主要为多环芳烃类和苯，而且在优控名单中的16种多环芳烃（PAHs）均可以检出，生产车间中主要是以气态的PAHs形式存在。 化工厂粉尘和废气经降雨、降尘进入土壤，对土壤造成严重污染。降落在地表的地面尘，通过雨水的冲刷而排入下水道，通过对郊区农作物灌溉，对土壤和农作物造成侵害。另外，地面尘会在下水道和排污区淤积成为淤泥，清理出的

1. 研究目的与意义In recent years, as more and more people pay attention to culture teaching in foreign language learning. In China, as a result of examination-oriented education system, teachers and students do not take culture learning as an important part of communication, thus students culture competence is being ignored. Researches suggested that their language competence was not consistent with culture competence. Therefore, knowing the situation of culture competence and culture teaching as well as putting forward solving strategies possess crucial practical and theoretical significance.2. 文献综述随着经济全球化的发展，我国的国际合作日益增多，对国际化人才的培养除了要注重语言能力的培养外，对跨文化交际能力的培养也必不可少。传统的外语教学基础学科语言学也从单纯的语言形式研究的禁锢中解放出来，衍生出了语用学、社会语言学等分支，进行了大量跨学科的研究，

1. 研究目的与意义、国内外研究现状（文献综述）传统的检测方法进行测量费时、费力, 且内部组织成分的测定需依靠破坏性检测方法受人工影响较大, 这严重影响了对萝卜进行快速、无损、准确的评价萝卜品质。无损检测是在不破坏被检测萝卜的情况下, 应用一定的检测技和分析方法对其外部品质和内部品质加以测定, 并按一定的标准对其做出评价的过程。高光谱检测萝卜内部品质可实现无损快速检测，提高经济效益和社会效益。张鹏，李江阔，孟宪军，等 可见/近红外漫反射光谱无损检测磨盘柿果实硬度的研究［J］.食品工业科技,2011.32:423-428.2. 研究的基本内容和问题利用高光谱图像技术研究萝卜内部品质时，光谱曲线随萝卜存放时间增长而改变。为了研究出光谱变化的根本原因，现以萝卜的呼吸强度、水分含量、糠心率、质构、粗纤维、木质素�

1. 研究目的与意义（文献综述） 随着现代数学方法的发展及应用数学方法研究金融经济问题的金融数学的问世，使得现代金融投资理论开始摆脱纯粹经验化操作和单纯描述性研究的状态，进入了定量分析这一高级阶段，并为投资者进行投资决策提供了指导．当今世界经济飞速发展，金融危机和市场波动频繁出现，我国的资本市场虽然在改革开放之后得到长足发展，但还不太完善和成熟，使得投资者面临越来越多错综复杂的金融投资决策的理论和实践问题，对投资组合优化问题的研究也越来越具有重要的理论和现实意义．目前,投资者对投资的需求越来越多样化,研究在投资过程中进行组合投资,最大化收益,最小化风险具有实际意义。近年来,智能算法的应用研究不断发展,智能算法应用于解决投资组合优化问题已经被越来越多的学者认同。 飞蛾火焰优�

1. 研究目的与意义（文献综述包含参考文献）The effect of context EFL reading 论语境对英语阅读的影响 Introduction The intention of this study is to explore the effect of context on EFL learners#8217; vocabulary learning ability. Context is closely related to an EFL learner#8217;s reading. So far much research has been done on the context (Urpo Kovala 2012; Robert S. Hatten 2014). But little has been done on the relationship between context and vocabulary learning ability. This study is aimed to make a comparison of vocabulary learning ability in different contexts in order to study the effect of context on EFL learners#8217; vocabulary learning ability Need for the study The motives for such research include the motives for much scientific inquiry. But in addition this knowledge of the relationship between context and vocabulary learning ability would have practical consequences. It might not only provide a proper method to improve vocabulary learning ability

1. 研究目的与意义（文献综述） 1.Purpose and significance This graduation design requires design the basic parameters through the given power, torque, maximum speed, braking conditions, driving conditions and national standards.Using previous knowledge to complete the structural design of the various parts of the chassis.And using the 3D software building the 3D modeling. Research background national and abroad In recent years, with the development of the science and technology and the improvement of living standard, people have put forward higher requirements for the reliability and comfort of the car.Driving axles is one of the most important parts in the automobile transmission system.In recent years,the cost of vehicle transportation is higher and higher because of the increase of oil prices,.Therefore, it is also important to improve fuel economy under the premise of ensuring vehicle power.In order to reduce fuel consumption,it is not only to save fuel

1. 研究目的与意义（文献综述包含参考文献） 文 献 综 述 1. 引言 小冲孔蠕变试验技术( Small Punch Creep Testing Technique， 简称SPC) 是1种在高温环境下，利用冲杆以一定速度冲压试样薄片并记录试样从变形到失效整个过程中的时间位移( 变形) 数据，借此分析得出材料各种性能参数的试验方法[1]。它源于小冲孔试验技术( Small Punch Testing Technique，简称SPT) ，本质上是一种微试样试验技术。 小冲孔试验技术是由Ames实验室Baik等人在上世纪80年代首先提出的[4]， 起源于受辐射材料性能的评定，随即在这个领域获得了广泛的应用。能评定从材料的塑性、韧性到断裂韧度，评定的材料从钢到各种金属、合金、复合材料和无机材料，应用的领域从原子能到化工、电力等。20多年来，小冲孔试验技术的主要研究工作是建立小试样与传统试样之间的关联性。经过

1. 研究目的与意义（文献综述包含参考文献）1. Introduction Along with the formation of the "global village", communication and exchanges between countries are increasingly frequent. English has already become the most common language in international communication. Skillfully using English is seemed as an indispensible part of modern people skills. English writing, as in a written form to convey information, emotion and communication ways, was naturally became the focus of English education. In our country, cultivating students' English writing ability has become a difficult point in English teaching. EFL Learners' second language writing competency is synergistically affected by many factors such as their language skills, vocabulary, grammar and thinking ability and so on. Apart from critical thinking abilities, the rest factors are easily acquired in classroom teaching. That is to say, the lack of critical thinking is becoming a common problem among most students i