英语2翻译

话题是social problems

1.适合小学生水平的。

节选自《中级美语阅读特训100篇》赖世雄著2011年出版外文出版社126个字

Overpopulation

One of the world’s most serious problems is overpopulation. There are too many people in the world. In 1994, the population of the world was 5.6 billion. Today, there are more than6 billion people. Today’s population growth is hard to believe and even alarming.

Most people admit that we must soon do something about overpopulation. It is

a problem that we must solve. If the population keeps growing, the world will

become a bad place to live. The natural environment will be destroyed. Forests will be cut down and wild animals will disappea r. There won’t even be enough food to eat. We have to decrease our population, or else people in the future will suffer. They will have to fight each other to stay alive.

当今世界最严重的问题之一就是人口过剩。这个世界的人口太多了。1994年，世界人口总数为56亿。如今，已经超过了60亿。当今人口的增长速度难以置信，甚至令人吃惊。

大多数人都承认，我们必须采取措施应对人口过剩。这是我们必须解决的问题。如果人口继续增长，这个世界将不适合居住。自然环境被破坏，森林被砍伐，野生动物也将消失。甚至没有足够的粮食养活人类。我们必须减少人口，不然子孙后代将会遭殃。他们也会为了生存而彼此争斗。

1.适合中学生水平的

节选自https://www.sodocs.net/doc/162605207.html,/tingli/news/voanews2010/133742.html

American Adults Obesity

In 1980, 15 percent of American adults were obese. Today, that number has doubled. Trust for America's Health, a non-profit group, has just issued its seventh report on obesity in America. "In 1991, there wasn't a single state that had an adult obesity rate over 20 percent," said Jeff Levi. "Now 38 states have adult obesity rates of more than 25 percent." Since last year, four more states reported adult obesity rates of more than 30 percent - meaning that at least 30 percent of their populations are obese. "There are many explanations," he said. "One, is we are just much less active than we used to be." Studies show a link between time on a computer or in front of a TV and obesity. Other studies point to high calorie fast food. But Levi says there are other risk factors. "Obesity is very much associated with poverty." said Levi. Fresh fruits and vegetables, lean meats and fish are expensive. And there are few grocery stores in low income neighborhoods. That means poor people find it difficult to buy

healthful food. "And poor people tend to live in neighborhoods that are less safe and have fewer opportunities for physical activity," he said. "So the combination of eating more calorie-dense food and having fewer opportunities for physical activity, that's what creates this obesity epidemic."

2.适合大学生的

《英语热点话题组合演练高一版》金民吕浙编著2012年出版湖北教育出版社273个字

Left-behind children

There are about 58 million left-behind children in rural china and over 40 million of them are under 14 years old, according to a report concerning the status of the left-behind children released by the All-China Women’s Federation early this February.

The report found mor e than half of the children left behind don’t live either parent. The telephone is often the only way they can contact their mother or father.

The report indicates that 8.7 percent left-behind children have no contact with their parents at all. The survey also found 49.7 percent of left-behind children prefer to live with their parents, and 44.1 percent of left-behind children do not want to live with their parents. 24.2 percent of left-behind children do not speak much with their caregiver.

Since most of these children are at critical stage of development, experts fear that they may develop psychological problems stemming from their parents’ absences.

Sun Yunxiao, a youth expert with the China Youth Research Center said: the younger the child is, the more family care the child requires. Intimate family care is necessary to every child’s growth. The biggest risk for left-behind children is that they lack family intimacy. They need good care and instructions in their everyday lives, including emotional suppo rt, study help and recreational time.”

Many provinces in China have now set up special schools to care for these children. Some provinces have also established charity funds for their future development. But experts add that with the numbers of left-behind children rising rapidly, more efforts will be needed by schools, society and rural families to care for children in China’s rural areas.

留守儿童

根据全国妇联在今年五月初发布的关于中国留守儿童地位的一份报告显示：中国农村地区共有5800万留守儿童，其中14岁以下的超过4000万。

报告显示，超过一半的留守儿童没有和父母的任何一方住在一起。电话是他们唯一联系父母的方式。该报告表明，8.7%的留守儿童从没有和父母联系过。调查还发现，49.7%的留守儿童更愿意和父母住在一起，44.1%的儿童不愿意和父母生活在一起，24.2%的留守儿童不愿意和他们的照顾着说话。

由于大多数的孩子正处于发展中的关键时期，许多专家担心，他们可能由于父母的缺席而产生一些心理问题。

中国青年研究中心的一位年青专家孙云晓说：“孩子越小，就越需要来自家

庭的关爱。亲密的家庭照顾对于每个孩子的成长都是必需的。留守儿童面临的最大风险就是缺少家庭的温暖。在日常生活中，孩子都是需要细心呵护和好的指导，包括情感支持，学习帮助和休闲时间。”

中国的许多省份现在已经建立了专门的学校来照顾这些留守儿童。有些省份也建立慈善基金也帮助孩子更好的发展。但是专家补充说，留守儿童人数的迅速增长，这需要学校，社会，和农村家庭付出更多的努力去关注中国农村地区的儿童。

高职高专实用英语第二册英语翻译

1.荷兰人在饭馆吃饭时真的会各自付账吗？ Do Dutch people really go Dutch at a restaurant? 2.另一方面来说，诚实的人会赢得别人的尊敬。 On the other hand, an honest man win other’s respect. 3.无论我说了什么，都请不要生我的气。 Whatever I say, please don’t be mad at me. 4.真是难以置信，这样简单的主意以前竟没有人想到。 It is incredible that no one had ever thought of such a simple idea before. 5.她的心情一会儿高兴，一会儿绝望。 Her mood alternate between happiness and despair. 6.我们必须相信我们所做的事情，即使别人不相信。 We must believe in what we do, even when others don’t. 7.在大城市里，在寒冷的冬季，许多老年人死于污染的空气。 During the cold winters in big cities, many old people die from the polluted air. 8.我过去习惯早起，并且在早餐前散步一小时。 I used to get up early, and take a walk for one hour before breakfast. 9.要在不到一周的时间内完成这项工作，时间困难的事情。 It is hard to finish this work in less than one week. 10.到这部戏剧的结尾部分，很多观众都被深深感动了。 A lot of audiences were deeply affected at the end of the drama. 11.他以前比现在上门出诊多得多。 He used to make many more house calls than he does now. 12.我们在阅兵场上肩并肩地排成一行。 We lined up on the parade ground shoulder to shoulder. 13.不管他在不在对我们的工作不会有影响。 Whether he is here or not will make no difference to our work. 14.关于这件事的说法实在令人难以置信。 That is a tall story about this event. 15.我们尽了最大的努力以确保仪式正常进行。 We have tried our best to keep the ceremony on the rails. 16.他在会议一开始就讲了几个笑话，让大家放松了一些。 He started the meeting with a couple of jokes to make us relax. 17.虽然生了一场大病，但他会赶上大家的。 He would catch up with the rest of us, although he had been ill seriously. 18.一旦人们看到有些东西确实有效，就更有可能接受它。 One people have seen that something really works, they are more likely to accept it. 19.除了法语外，他还得学日语。 In addition to French, he has to learn Japanese. 20.这影片如此感人以至我们禁不住流下泪来。 This movie is so impressive that we can’t help crying. 21.把这么多书分类整理要花很多的时间。 It takes plenty of time to sort so many books. 22.这次地震带来了相当大的灾难，同样也带来了经历和力量。 The earthquake brought considerable misfortunes and it also brought experience and strength. 23.大多数人对心理健康问题几乎一无所知。 Most people know little about the mental health problem. 24.他们容忍了儿子的行为。 They have put up with their son’s behavior. 25.他长期以来致力于高科技的研究和开发。 He has been devoted to the research and the development of high tech all the time. 26.今晚中央电视台将播出一部名为“同一个世界，同一个梦想”的纪录片。Tonight CCTV will air a documentary named “One word, one dream.” 27.这些课程吸引了各行各业的人。 These courses attract people from all walks of life. 28.他们正在研究如何在地震中更好的逃生。 They are studying better ways to survive in earthquake. 29.这种做法不符合我们的政策。 Such act would be in disaccord with our policy. 30.他称她为他最好的一半。 He refers to her as his better half. 31.我们所能做的就是培养自己去全力对付它，而不是去躲避它。 What we can do is to train ourselves to deal with it, not to avoid it. 32.他们设计将疾病控制在小范围内。 They manage to limit the disease within a small area. 33.我既没有钱也没有时间去旅行。 I have neither money nor time for travelling. 34.此外，购买新车也是主要消费之一。 In addition, purchasing a new car is also a major spending. 35.他的课业很好。 He is getting on well with his school work. 36.没有人确切地知道当初人们是如何学会保存食物的。 No one knows for sure how people first learned to preserve food. 37.她没有领会他话中的幽默。 She didn’t pick up on the humor in his words. 38.这是对我们共同度过的那些美好时光的留念。 This is a reminder of the good time we spent together. 39.每个国家、每个民族都有自己的历史文化传统。 Every country and every nation has its own historical and cultural traditions. 40.几年以后，那些山也将被树木覆盖。 In a few years’ time, those maintain will also be covered with forest. 41.光明的未来往往建立在对过去遗忘的基础之上。 The bright future will always be on the base of a forgotten past. 42.我们在父母家优美的环境中放松了一下午。 We spent the afternoon relaxing in the beautiful surroundings of my parent’s home. 43.我需要一把剪刀把这篇报纸文章剪下来。 I need a scissors to cue off the article of newspaper. 44.这是到目前为止我们所收到的最大一项捐赠。 This is the biggest donation we have received up to now. 45.我们对做这么多作业感到厌倦。 We are tired of doing so much homework. 46.拼写问题可能也和书写不整洁有关。 Spelling problems can be related to the untidy writings.

(完整版)医学专业英语翻译及答案

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钱：money 整发做花：hair setting 发型设计：hair design 手指卷法：pin curl 化妆：make up 按摩：massage 全套服务：full service 快速服务：quick service 免费服务：free service 指甲保养：nail care 产品(product)&工具(instrument)头发：hair 冷烫液： cold wave/ perm 洗发精：shampoo 护发霜：hair care/conditioner 发胶：gel 定型液：hair spary 染发剂：hair color 发雕：lotion 正常(一般)：normal 受损：danger

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测绘专业英语原文和部分翻译(1-39)

Table of Contents Uuit 1 What is Geomatics? （什么是测绘学） (2) Unit 2 Geodetic Surveying and Plane Surveying（大地测量与平面测量） (6) Unit 3 Distance Measurement（距离测量） (10) Unit 4 Angle and Direction Measurement（角度和方向测量） (14) Unit 5 Traversing （导线测量） (17) Unit 6 Methods of Elevation Determination（高程测量方法） (21) Unit 7 Robotic Total Station （智能型全站仪） (25) Unit 8 Errors in Measurement（测量工作中的误差） (29) Unit 9 Basic Statistical Analysis of Random Errors (32) Unit 10 Accuracy and Precision （准确度和精度） (35) Unit 11 Least-Squares Adjustment (38) Unit 12 Geodesy Concepts (40) Unit 13 Geoid and Reference Ellipsoid (42) Unit 14 Datums, Coordinates and Conversions (44) Unit 15 Map Projection (46) Unit 16 Gravity Measurment (48) Unit 17 Optimal Design of Geomatics Network (50) Unit 18 Construction Layout （施工放样） (53) Unit 19 Deformation Monitoring of Engineering Struvture (56) Unit 20 Understan ding the GPS（认识GPS） (59) Uuit 21 Understanding the GPS (II) 认识GPS(II) (62) Unit 22 Competition in Space Orbit（太空轨道上的竞争） (64) Unit 23 GIS Basics（GIS 的基础） (69) Unit 24 Data Types and Models in GIS GIS中的数据类型和模型 (75) Unit 25 Digital Terrain Modeling（数字地面模型） (79) Unit 26 Applications of GIS (83) Unit 27 Developments of photogrammetry (87) Unit 28 Fundamentals of Remote Sensing （遥感的基础） (90) Unit 29 Digital Image Processing and Its Applications in RS (94) Unit 30 Airborne Laser Mapping Technology（机载激光测图技术） (99) Unit 31 Interferometric SAR(InSAR) (102) Unit 32 Brief Introduction toApplied Geophysics (104) Unit 33 Origon of Induced Polarization (105) Unit 34 International Geoscience Organization (108) Unit 35 Prestigious Journals in Geomatics (110) Unit 36 Relevant Surveying Instrument Companies (115) Unit 37 Expression of Simple Equations and Scientific Formulsa (116) Unit 38 Professional English Paper Writing (119) Unit 39 Translation Techniques for EST (127)

机电工程专业英语翻译(2)

包含16、17、18、22、23、27单元 As the arbiter of quality via the deviation from drawing procedure, quality planning has the database to evaluate performance of the various shop and support functions.作为产品设计与制造偏差的评判者，质量规划部门可以通过数据库对产品的各个加工工序及制造情况进行评估Annealing is a generic term denoting a heat treatment that consists of heating to and holding at a suitable temperature followed by cooling at a suitable rate 退火：热处理的一个通用术语，指的是加热到一定温度并保温，然后以合适的速度冷却Apart from the smoothenss of operation thus obtained, a great improvement is usually found in the surface finish on the work and the tool can make heavier cuts without detriment and will last considerably longer without regrinding除了能使机床运行平稳之外，液压驱动在机床上还有许多其他优越之处。例如，可以改善工件表面的光洁度；可以在不损坏刀具的前提下增大刀具上的作用载荷；可以进行长时间的切削加工，而无需再次刃磨刀具等A robot is an automatically controlled, reprogrammable, multipurpose, manipulating machine with several reprogrammable axes, which may be either fixed in place or mobile for used in industrial automation applications机器人是一种自动控制，可编程，多功能的，由几个可重复编程的坐标系来操纵的机器装置，可固定或移动的方式应用于工业自动化中And, whether you know it or not, many papers are rejected by journal editors because of a faulty Discussion, even though the data of the peper might be both valid and interesting.不知你是否知道，尽管许多论文中的数据正确而有根据，且能够引起人们的兴趣，但讨论部分写得不好也会使其遭到期刊编辑的拒绝Because robots can perform certain basic tasks more quickly and accurately than humans, they are being increasingly used in various manufacturing industries.因为机器人可以比人更快更准确地完成某些基本任务，所以广泛地用于制造业By comparing those feedback signals with the values set by the programmer, the close-loop controller can conduct the robot to move to the precise position and assume the desired attitude, and effector can perform with very high accuracy as the close-loop control system can minimize the discrepancy between the controlled object and the predetermined references.通过将反馈信号与程序设定值相对比，闭环控制器能引导机器人向准确的位置运动并实现期望的状态。闭环控制系统可以使被控目标与预定值之间的误差达到最小，终端执行机构可以高度精确的运作Because it is not a sentence, with the usual subject, verb, object arrangement, it is really simpler than a sentence(or, at least, usually shorter), but the order of the words becomes even more important.它不必像通常的句子那样具有主语、谓语动词和宾语结构。它确实比句子简单（或者，至少通常比较短，但是也正因如此，词的排列顺序显得更为重要Don’t be shy;discuss the theoretical implications of your work, as well as any possible practical applicatons.大胆地论述研究工作的理论意义以及任何可能的实际应用Electrically driven oil pressure pumps establish an oil flow for energy transmission, which is fed to hydraulic motors or hydraulic cylinders,

定计划-简单实用英语翻译

定计划-简单实用英语翻译 451. What do you plan to do tomorrow? 明天你打算做什么？ 452. I doubt that I'll do anything tomorrow. 明天我恐怕什么也不做。 453. Please excuse me for a little while. I want to do something. 对不起，请稍等一会儿，我要办点事。 454. I imagine I'll do some work instead of going to the movies. 我想干点活，不去看电影了。 455. Will it be convenient for you to explain your plans to him? 你把你的计划向他讲一下，方便吗？ 456. There's nothing to do because tomorrow is a holiday. 明天是假日所以没事可做。 457. What's your brother planning to do tomorrow? 你的兄弟明天打算做什么？ 458. He can't decide what to do. 他决定不了要干什么。 459. It's difficult to make a decision without knowing all the facts.

不了解全部事实，很难作决定。 460. We're trying to plan our future. 我们正点想法替将来作打算。 461. That's a good idea. 那是个好主意。 462. I'm hoping to spend a few days in the mountains. 我希望在山区住几天。 463. Would you consider going north this summer? 今年夏天你考虑到北方去吗？ 464. If there's a chance you'll go, I'd like to go with you. 如果你有机会去，我想和你一起去。 465. After you think it over, please let me know what you decide. 等你想好了，请把你的决定告诉我。

力学专业英语部分翻译 孟庆元

1、应力和应变 应力和应变的概念可以通过考虑一个棱柱形杆的拉伸这样一个简单的方式来说明。一个棱柱形的杆是一个遍及它的长度方向和直轴都是恒定的横截面。在这个实例中，假设在杆的两端施加有轴向力F，并且在杆上产生了均匀的伸长或者拉紧。 通过在杆上人工分割出一个垂直于其轴的截面mm，我们可以分离出杆的部分作为自由体【如图1(b)】。在左端施加有拉力P，在另一个端有一个代表杆上被移除部分作用在仍然保存的那部分的力。这些力是连续分布在横截面的，类似于静水压力在被淹没表面的连续分布。 力的集度，也就是单位面积上的力，叫做应力，通常是用希腊字母，来表示。假设应力在横截面上是均匀分布的【如图1(b)】，我们可以很容易的看出它的合力等于集度，乘以杆的横截面积A。而且，从图1所示的物体的平衡，我们可以看出它的合力与力P必须的大小相等，方向相反。因此，我们可以得出 等式(1)可以作为棱柱形杆上均匀应力的方程。这个等式表明应力的单位是，力除以面积。当杆被力P拉伸时，如图所示，产生的应力是拉应力，如果力在方向是相反，使杆被压缩，它们就叫做压应力。 使等式(1)成立的一个必要条件是，应力，必须是均匀分布在杆的横截面上。如果轴向力P作用在横截面的形心处，那么这个条件就实现了。当力P没有通过形心时，杆会发生弯曲，这就需要更复杂的分析。目前，我们假设所有的轴向力都是作用在横截面的形心处，除非有相反情况特别说明。同样，除非另有说明，一般也假设物体的质量是忽略的，如我们讨论图1的杆

一样。 轴向力使杆产生的全部伸长量，用希腊字母δ表示【如图1(a)】，单位长度的伸长量，或者应变，可以用等式来决定。 L是杆的总长。注意应变ε是一个无量纲的量。只要应变是在杆的长度方向均匀的，应变就可以从等式(2)中准确获得。如果杆处于拉伸状态，应变就是拉应变，代表材料的伸长或者延长如果杆处于受压状态，那么应变就是压应变，这也就意味着杆上临近的横截面是互相靠近的。 当材料的应力和应变显示的是线性关系时，也就是线弹性。这对多数固体材料来说是极其重要的性质，包括多数金属，塑料，木材，混凝土和陶瓷。处于拉伸状态下，杆的应力和应变间的线性关系可以用简单的等式来表示。E是比例常数，叫做材料的弹性模量。 注意E和应力有同样的单位。在英国科学家托马斯·杨(1773 ~ 1829)研究杆的弹性行为之后，弹性模量有时也叫做杨氏模量。对大多数材料来说，压缩状态下的弹性模量与处于拉伸时的弹性模量的一样的。 2、拉伸应力应变行为 一个特殊材料中应力和应变的关系是通过拉伸测试来决定的。材料的试样通常是圆棒的形式，被安置在测试机上，承受拉力。当载荷增加时，测量棒上的力和棒的伸长量。力除以横截面积可以得出棒的应力，伸长量除以伸长发生方向的长度可以得出应变。通过这种方式，材料的完整应力应变图就可以得到。 图1所示的是结构钢的应力应变图的典型形状，轴向应变显示在水平轴，对应的应力以纵坐标表示为曲线OABCDE。从O点到A点，应力和应变之间是

专业英语翻译(路桥方向,第三版)2

Lesson9线形设计 竖直曲线和水平曲线的布置组成了高速公路的线形，竖曲线包括直的纵坡线和连接纵坡线的抛物线.平曲线包括直线段和连接它们并改变方向的圆曲线段.线形的设计主要依赖于高速公路设计速度的选择，与自然地形相符合的线形造价最小。通常这种情况是不可能的，然而，因为设计师必须遵循一定的设计标准，而这些标准也许并不能适应地形○1，重要的是既定部分的线形必须遵循一致的标准来避免高速路在竖直和水平定线时产生突变，同样，竖曲线和平曲线在设计是要相互补充协调，，这样才能设计出一条安全的和更有吸引力的高速公路。为了达到这一点，一个应该考虑的因素是适当地保持直线坡度和平曲线曲率的平衡，处理好平曲线和竖曲线间的相互位置。例如，在较大半径的陡坡上设置平曲线是一种较差的设计，同理，如果在一个明显的凸形竖曲线的顶部或附近设置小半径平曲线，或在明显的凹形竖曲线底部或附近设置小半径平曲线，，这将导致这里是一个危险部分。因而在初步设计阶段把竖曲线和平曲线的协调综合考虑是很重要的。 高速公路的竖向线形是有被称之为纵坡或切线的直线部分和与之相连的竖曲线组成，因而竖向线形的设计包括直线部分合适坡度的选择和竖曲线的设计。路线所穿越区域的地形对书香线形设计有极其重要的影响。 坡度对重交通路线的影响必须被考虑，，如果是陡坡或长坡会使重交通车辆的车速降低很快，注意到陡坡不仅影响重车的性能还影响轿车的性能，为了限制坡度对车辆的影响，任何高速路的最大坡度都应明智选择。高速公路的最大坡度取决于设计速度和设计车辆，普遍认为4%--5%的坡度对小客车的影响不大或没有影响，除非是重量与功率比比较高的车，例如那些小型车和微型车。○2当坡度大于5%时，客车在上坡时速度进一步降低在下坡时进一步增加，坡度对卡车的影响大于对客车的影响，广泛的研究结果表明，卡车在下坡时速度增加5%，而在上坡时减小接近7%，这取决于坡度比例和坡长。最大坡度的确立依据是高速公路上的设计车辆的操作性能，最大坡度的变化范围从设计时速70英里时的5%到设计时速为30英里时的7%-12%,这取决于高速公路的类型。另一方面，当坡长不足500英尺时，且下坡方向为单向路线时，最大纵坡或许可以提高1%-2%，特别是在交通量较低的乡村道路。 最小纵坡取决于排水条件，零坡度的道路被用在有足够横坡足以排尽路表水的路段，当路面有限定时，纵坡应能排尽纵向流动的路表水，在这种情况下习惯上选用最小0.5%的坡度，有时，在有合适路拱和硬地的高等级路面建设中，这个坡度可能会被减小到0.3%。 竖曲线通常用于直线纵坡间的逐渐过渡以利于车辆平顺的通过高速路，这些竖曲线通常是抛物线形的，竖曲线的最小长度的选定取决于所选抛物线的特性，竖曲线分凸形和凹形竖曲线。 竖曲线的设计应满足的主要标准有：能提供最小的停车视距，要有充足的排水，行车舒适，外观良好。凸形竖曲线仅需满足第一条标准，而凹形竖曲线四条标准都要满足。 水平线形有直线和平曲线组成，平曲线通常是被分割的圆曲线，他有一定的半径可使车辆平顺的通过。 因此，水平线性的设计必须确定最小半径，曲线长度，以及计算从切线到曲线的平面支距，以有助于曲线的定线，○4在有些情况下，为了避免直线段的曲率半径无限大到圆曲线段曲率半径为一定值之间的突变，通常需要在他们之间插入一段曲率半径逐渐变化的曲线，这种曲线称之为回旋线或缓和曲线。 有四种类型的水平曲线：简单曲线，复曲线，反向曲线，回旋线。 简单曲线是圆弧的一段,然而复曲线由两条或两条以上的转向相同的连续曲线组成，任何两条曲线都有一个相同的切点，，这些曲线可用来获取较理想的水平线形，特别是在立体交叉处，交叉匝道，特殊地形区情况下的高速公路，为了避免线形的突变，任何两条依次相连的简单曲线组成的复曲线半径不宜相差过大，。美国公路学会建议，在交叉路口复曲线半径的最大半径和最小半径之比不能超过2：1，在这里司机可以适应曲率和速度的突变,让人满意的立体交叉道的最大比率为1.75:1.虽然2:1也被使用。 为使大曲率曲线与急弯曲线间平缓过度，并使曲线半径的减小有一个合理的渐变率，每条曲线的长度不能太短。 反向曲线通常是由两条半径相等且具有同一切点转向相反的简单曲线组成，他们经常用于高速路的线形改变。 反向曲线很少被推荐使用是因为突变的线形是司机感到很难在同一车到驾驶，如果有必要设计反向线形，合理的设计是由简单曲线组成，中间插入一段有足够长度的直线以达到全超高。○5作为一种选择，简单曲线或许被等效长度的回旋线隔开。 缓和曲线设置在直线段与圆曲线段之间或两个不同半径的圆曲线之间，缓和曲线的作用是在车辆进入或离开圆曲线时为车辆提供一个逐渐增加或降低的向心力，设置直线段与圆曲线之间的缓和曲线的曲率由直线段末端的