1. 研究目的与意义 阅读被认为是日常生活和工作中非常重要的一项技能。对于大多数外语学习者来讲,通过与目的语会话者面对面交流进行学习的机会是非常有限的,因此,最方便的方法便是通过阅读与之接触。在外语测试中,阅读理解部分在整个测试中占了非常大的比重,由此可见其重要性。因此,设计出好的阅读理解试题是保证其测试成功的一个重要方面。大学期间，说到英语考试，通常绕不开两个种类：外国英文考试（托福、雅思等）和中国英文考试（四六级）。二者虽然都是英文考试，但是因为主办方和目的的不同，考察重点和题型都有所区别，对于打算参加的考生来说，备考的方式自然也要有所区别。本文将重点对比研究各项考试中的阅读理解这一题型。 本文将参考大量对雅思托福及四六级考试中阅读理解考查方法及效度进行研究的中外文�

1. 研究目的与意义（文献综述） Unmanned electric vehicle is a kind of intelligent vehicle that can feel the surroundings with various sensors and control the steering and speed of the vehicle based on the acquired information such as roads condition, vehicle locations and obstacles, which reduces the effort of human factors on driving safety. At the same time, unmanned electric vehicles only needs to use electricity instead of oil which contributes to serious environmental pollution. Moreover electric energy can be obtained from wide range of resources: such as hydro, wind, nuclear materials, solar, etc. With the continuous development of technology, more and more unmanned electric vehicles can be developed in the near future. In early 1980s, the US Department of Defense gave large-scale funding of ALV (Autonomous Land Vehicle) research. Unmanned vehicles were first successfully applied to the highway with high degree of structural environment, some of the representat

1. 研究目的与意义 迄今为止，虽然世界上还没有真正意义的量子计算机，但是世界主要经济发达国家都在制定战略性规划，各国有代表性的实验室正以巨大的热情投入人财物，期望在新一代计算机的科学与技术上占据领导地位。正因为实现量子计算机的技术困难重重，而量子计算机的实现必将为信息科学与通信技术带来革命性的突破，所以量子可逆逻辑电路的设计、优化与测试等方法的研究作为量子信息与量子计算理论的基础研究越来越受到理论研究者与应用研究者的关注。 可逆电路的优化是可逆逻辑综合的关键问题之一。提出的许多可逆逻辑综合算法，虽可以较高效率综合出电路，但并非最优电路。除了穷举法之外，几乎所有可逆逻辑的综合方法均不能保证结果的最优性，所以可逆电路的优化有着广泛的需求。量子可逆电路优化的目标，�

1. 研究目的与意义（文献综述包含参考文献）文献综述 . 文献综述 1，水质污染近年来 在地下水总重迅速减少，水位持续下降的同时,地下水资源还面临着另外一个不容小觑的问题:日渐严重的污染。 当前，我国工业经济发展速度很快，各项工业经济指标快速增长，但是工业生产运用大量化学原料,排出大量重金属废料，会对水环境造成严重污染，依据相关部门在调查后给出的结论,如今,在国内超过半数的地区的地下水其水体质量都处在逐步的恶化中，被多种多样的工农业生产和日常生活产生的污染物乃至放射性物质所污染的地下水，正在逐步地侵蚀当地人民的健康状况。同时，地下水的水质恶化,特别是由放射物所引起的污染,正在进一步地向城市周边扩散污染,进而对农业用地的土壤资源造成严重的消极作用,导致农业生产受到严重的负面影响，使得我

1. 研究目的与意义一、内容甲型肝炎病毒IgG抗体检测试剂盒主要由预包被板、酶标记物、阴性对照、阳性对照、底物液AB、终止液、浓缩洗涤液组成。其中预包被板和酶标记物及阴性对照是最为重要的组成部分。预包被板的包被工艺以及抗体的浓度配比，抗原、酶的稀释倍数都会对检测结果的准确性、稳定性产生重要影响。所以在原有产品的基础上，对不同生产商的小样抗原抗体进行质量优先实验筛选，再对抗体浓度配比，抗原和酶的稀释倍数进行新的实验设计。最后使用酶标仪对优化生产工艺后的试剂盒产品进行定性检测，数据对照评估，得出结果。 二、意义甲型肝炎病毒IgG抗体检测试剂盒适用于临床甲型肝炎的辅助诊断或者疫苗效果检测，是一种比较简单便捷的甲型肝炎病毒IgG抗体检测方法。在原有甲型肝炎病毒IgG抗体检测试剂盒工艺的基础�

1. 研究目的与意义（文献综述包含参考文献）One of the environmental problems faced by people in the world is environmental pollution due to the general knowledge of the community about waste management. So that waste in the community does not accumulate, a special action is needed, namely recycling waste. The process of recycling waste is carried out differently according to its type. Organic waste can be recycled into compost or bio gas. Metal and non-metal inorganic waste can be recycled by means of reprinting, including printing or remelting without reducing the quality of the inorganic waste. In general, sorting waste is still done manually by hand. For example, to sort metal waste and non-metal waste from pile of garbage is still carried out by human hands manually. That matter less effective in terms of time and energy. With these conditions, one solution is to build a microcontroller implementation system Sorting Metal And Non-Metal Waste In The Trash.The proces

1. 研究目的与意义（文献综述） 在汽车的研发过程中，车辆的制动性和操纵稳定性的测试需要做成实际的样车，然后对其进行实验以及反复的修改，耗费巨大的人力、物力和时间成本，另外有一些实验具有很大的危险性，难以进行。然而，采用虚拟实验仿真平台则只需要样车的整车模型。做仿真实验时只需要修改整车模型的相关参数就可以的到不同的实验结果，直到得出满意的实验结果。这样的仿真实验大大缩短了设计周期，提高了产品的竞争力。 利用仿真模型进行模拟实验，能在设计过程更早阶段掌握更多的信息、尽可能减小设计风险，掌握产品设计机理；能在实物样机试制前对整车性能进行分析预测，在设计阶段研究产品结构对性能影响的规律，并可直接进行设计参数的分析、优化，提高设计质量；能避免多次修改实物样机、重复实物实�

1. 研究目的与意义（文献综述包含参考文献）文 献 综 述1.引言孔的特性直接影响到膜的性能和使用寿命，因此对孔的尺寸及其分布的测定是在膜的研究、制备、使用等过程中一项重要的内容。目前用于测孔的方法有直接法和间接法两类。前者主要通过各种显微镜( 如光学显微镜、扫描电子显微镜、透射电子显微镜、扫描隧道显微镜、原子力显微镜等[1-5])直接观察及测量材料表面和断面的孔径。间接法又包括泡点法(又称毛细流动法)、压汞法、氮气吸附法、液液置换法、气体渗透法、截留分子量法等[6-11]，这些方法都是通过测量与孔径相关的物理参数来间接计算过滤材料的等效孔径。其中，泡点法利用流体在孔道内流动的物理规律来测定孔径及其分布，较真实的反映了流体通过孔道的实际情况，能够较准确的测量孔喉直径，因此广泛应用于滤膜孔径�

全文总字数：17891字1. 研究目的与意义（文献综述） 1. Purpose and significance of the study With the development of economy, the improvement of people's living standard, the rapid increase of national automobile holding and the rapid increase of automobile quantity undoubtedly bring great pressure to the environment and resources. At present, most car companies have a high degree of recognition and attention to automotive lightweight technology. With the increase in the number of cars, gasoline consumption continues to increase. At present, our country's automobile oil accounts for 5% of the total oil consumption, and its external dependence is 55.5%, which has exceeded that of the United States. Facing the great pressure of energy and environmental protection, the development of automobile industry in our country is seriously restricted. The survey data show that our country consumed fuel per kilometer on average four years ago In order to achieve the goal o

全文总字数：18514字1. 研究目的与意义（文献综述） Ⅰ. Research Objective and Significance Asteering system is a series of devices used to change or keep a car moving orgoing backwards. The function of the steering system is to control thedirection of the car according to the driver's wishes. Car steering system isvery important to the safety of the car, is the car safety must pay attentionto one of the two systems, so the car steering system parts are called securityparts. Automobilesteering systems are divided into two categories: mechanical steering systemsand power steering systems. The mechanical steering system takes the driver'sphysical strength as the steering energy, and the power steering system is asteering system that USES both the driver's physical strength and the engine(or motor) power as the steering energy. Its emergence and development also hascertain process, the first is the traditional mechanical steering system, thenon the basis of th