第一篇:新闻专业外文翻译
传播起什么作用
新闻与传播学院新闻07-1班武刚
我们是传播的动物;传播渗透到我们所做的一切事情中。它是形成人类关系的材料。它是流经人类全部历史的水流,不断延伸我们的感觉和我们的信思渠道。由于我们已实现从月球进行宽波段通讯联络,我们目前正在寻求同其它世界的其它生物进行交谈。传播是各种各样技能中最富有人性的。
但是,让我们更清醒地推敲一下这个说法。传播究竟能为我们做些什么,我们又利用传播做了什么?
这个问题乍听起来,好象问别人“为什么要吃饭?”或“为什么要睡觉?”一样愚蠢。我们吃饭是因为我们饥饿。我们睡觉是因为我们困倦。我们喊叫“救火!”是因为房子正在燃烧。我们说“对不起!”是因为我们碰撞了别人.
对我们说来,传播是一种自然而然的、必需的、无所不在的活动。我们建立传播关系是因为我们要同环境、特别是我们周围的人类环境相联系。正如上文引用的萨皮尔所写的那段话一样,社会是一个主要由传播所维持的这类关系组成的网。对一名观察者说来,传播就象血液流经人的心血管系统一样流过社会系统,为整个有机体服务,根据需要有时集中在这一部分,有时集中在另一部分,保持接触和平衡以及健康,我们已经习惯于生活在传播的汪洋大海中,以致于很难设想要是没有传播.我们将怎样生活。
不妨设想一个没有传播的社会是一个什么样的国际社会?近几年里,美国和中国之间的官方保持着毫无表情的沉默,但是却通过许多渠道进行了交流:经由大众媒介发表各种声明、采取显然是要转达讯息的政治行动、通过第三国彼此收集对方的情报。甚至有必要在中立国家安排大使级的“非官方”会议。双方交换了各种各样特殊的使节,如乒乓球运动员,通过他们,一个国家的高级官员能够异常坦率地向另一个国家的人民发表讲话。
在没有传播的情况下,群体社会又是什么样的社会呢?西多会有一个“沉默的”苦修会教派的寺院禁止交谈,但不禁止传播。僧侣们只有靠无数的行动传播:一瞥或一笑,行政管理行动,按日程办事,遵守成员们通过虔诚的行动互相交流的某种承诺和信仰上的团结一致。假定有一个隐士从人间世界退隐到他在山里的洞穴去冥思。他试图避免与他人交流,除非是有人来向他求教。但是,沉思冥想这个行为本身就意味着内心的传播。这个隐士是在挖掘自己过去储存的信息,加上从他的脱离人的环境所得到的信息,不断思考,自己同自已讨论。他是在同自己的每日祈祷书和自己的书籍进行交流,而旦在某种意义上说,是在同所有那些对他起过影响的思想进行交流。他的退隐到山洞是向全体人类传播一个讯息。而且他可能象圣方济一样同鸟类交谈。
因此,即使是在极其罕见的情况下,传播也照样在进行着。平时我们的大多数人对此是无意识的,除非有时自我意识到它。一名专业人员对于自己正在为一家杂志写的文章也许是很有自我意识和自我批评的。一个政治家对于自己正在背诵的演讲可能是有自我意识的。但是生活漫无目的的孩子们却是自然而然地发出和接受汛息,以他们整个有机体表现举止行动,不太考虑怎样做这种行动。他们知道喊一声“爸爸”和后来知道讲话时用‘请”字会受到父母的奖赏,但是即使这种表现也是自然形成的。他们喜欢看电视和回忆他们最喜欢的节目。他们到学校去,对自己必须写的作文题变得有点自我意识,或者就一个小伙子来说,对于第一次给一个姑娘打电话变得有点自我意识。但是,除非他们讲话有缺陷,或者是耳聋,或者其它某种痛苦的困难,他们都是以他们自然学会的方式进行传播,利用他们摸索学会的举止
来带来他们想取得的结果。
即使在儿童长大为成年人而且变得比较意识到传播的影响和以不同方式进行传播的后果时,他们也仍然觉得难以用言词描述为什么他们耍象他们所做的那样进行传播。几年前,纽约的报馆罢工,伯纳德?贝雷尔森利用这个机会对一批纽约人进行抽样调查,问他们在没有报纸的情况下感到失去了什么。他的目的当然是试图找出为什么他们读他们所读的东西。但是,这些人甚至很难说出他们失去了什么。他们可能列举出他们不再收到的一些服务性情报——如天气预报、电影上映时间表、晚间广播节目等——但是使他们烦恼的主要并不是因为失去这些情报。
许多人担心他们正在失去某些对自已有重要意义的具体情报:回答问题的好几位年纪大的人认为自己有些朋友可能死了而自己却一点也不知道。还有感到比较恼火的是隐隐约约觉得自己生活中好象缺少什么东西。有的人说,失去了“同世界的联系,失去了被接触的感觉”,或者简单地说少了“某件我每天都做的事”。这项调查的最重要发现也许是了解到读报行为已多么充分地纳入人们的日常生活中,这种传播行为已成了多么自然的事,以及最初采用传播的理由已多么深深地消失在过去的阴影中。
这就是为什么难以用言词说明“传播起什么作用”的一个原因,另一个原因是利用传播的各种理由往往是非常复杂而且不一定能从表面看出的。还有一个原因是明显(有意)的传播的功能,并不始终考虑潜伏(无意)的传播的功能。这是罗伯特.默顿说的话,实际上,他的意思是,传播的实际后果并不始终是有意的后果。例如,提醒别人可能患癌症的结果也许不是引导别人去体检,而是把他们吓得不敢去医院。见面时高兴地对人说一声“早上好”可能不是导致友谊。而是引起别人怀疑打招呼的人是想借钱。最后由于我们关于传播功能的分析大部分不得不从外部进行,我们发现自己总是试图看到黑匣子的里面。
但是,我们每人至少能看见一上黑匣子的里面,那就是我们自己的黑匣子。你进行传播的目的是什么?我为什么要传播?
今天早上我从家里走出来,看见一个穿运动衫的人,我朝他笑笑说“早晨好”。如果有人真的照字面译成新几内亚的部族语言可能会有困难。我不是说这是一个“好的”——就是说不错的——一早晨吗?不,这是一个天气恶劣的早晨,下着滂沱大雨,水从山上冲下来,几乎使我浸泡在水里。我是不是就象我们说“吉样的星期五”一样从某种道义上的角度谈起这个早晨的好呢?不,这一天跟其它日子一样。我是不是祝愿他有一个“好”—一就是说愉快的——早晨呢?在某种程度上有这个意思,但是他看上去完全能够安排他自已的早晨,而事实上我感到相当恼火的是因为他能够在海边度过这个早晨,而我却必须去上班。那么我同他说话的意思究竟是什么呢?我能够作出的最合理的解释是,我是在履行我们自己的部族礼仪。我是在向他传播,我属于他的群体,属于他的文化,不是一个外人,不是一个反叛者,也不是一个威胁。换句话说,我是在证实一种惬意的关系。
他向我说“你今天早晨好吗?”我怀疑他很关心我的健康。他是在做我刚才在做的事情——传播社会成员资格和某种程度的友谊。他期望我会说“很好”,我也的确这么说了。事实上,他们似乎是在向我们周围投射社交雷达射束,好比船只在雾中航行或飞机依靠仪器飞行一样,证实我们的身份以及在雷达屏上出现的别人的身份,证实我们在一个友好的文化群体中的成员资格,做着我们早就知道要我们去做的事。那些把人类关系说成是“晚间经过的船只”的作家,并不是描述我们最密切最亲密的关系,而是描述我刚才谈起的那种接触。而它们占了我们生活中的接触的很大一部分。尽管如此,传播对我们说来们起到雷达的作用,是说明身份的信号,也是预警系统。或者至少在一名观察者看来是如此。
再举个例子:在烟雾缭绕和大家闲聊的鸡尾酒会上,一位年青人问一位漂亮姑娘,“抽烟吗?”表面上,他是在问她要不要抽支烟。实际上,他是在传播兴趣,而且毫无疑问希望
她以同样的方式作出反应。他以问她要不要抽烟的方式传播自己在一种文化中的成员资格,他大概希望她以取一支烟的方式,或者至少以微笑谢绝方式,来证实她的成员资格,而不会因为她不赞成抽烟或认为男青年不应未经介绍就同姑娘说话而打他一记耳光。换句话说,这个局面同我们刚谈起过的局面是一样的:雷达、证明身份、预警。如果这个姑娘作出良好的反应。他接着要问的问题很可能是,“我在什么地方见过你吗?”实际上,这个问题同他究竟见没见过她是毫无关系的,这是一种搭讪,以便再多了解她一点,也许是要估计一下这个偶然的相识是否可能成为持久的相识。换句话说,雷达行为与手段行为合并了。再举个例子,我通常在每天傍晚六点钟左右听到教堂的钟声。我倾听钟声是因为很难做到不予理会,还因为它们的声音悦耳,同日落的景色和傍晚的荫影很调和。钟声使我产生一种满足和温暖的感觉。此外,钟声对我起了报时作用。如果我还在工作的话,那么是开始考虑作一次傍晚的游泳和喝一杯鸡尾酒的时候了。黄昏渐渐开始,是回顾我曾经制订的计划或答应的约会的时候了。此外,钟声提醒我.宗教是我所属的文化的一个组成部分,此刻,我的一部分邻居正在祈祷。钟声还在我脑海中构成令人悦目的图象:教堂、烛光、风琴、无伴奏齐唱乐和态度谦虚的人。
圣玛丽教堂通过那些钟声试图传播什么呢?它正在号召信徒做礼拜。但是,参加那个特定仪式的大多数人,有的也许是听到钟声来的,有的也许没有听到钟声就来的。钟声的目的也是要传播某种人们可以得到的精神援助,假如有人需要这种钟声所象征的精神援助的话。钟声的目的也许是要让我这样的罪人听到,提醒我们注意我们的宗教义务,尽管我们很难得进圣玛丽教堂。圣
玛丽教堂的钟声也许还在传播,它自已是一种古老和光荣的传统的一员,这种钟声作为这个传统的标志已整整好几个世纪。
因此,传播行为的全部意义是难以从表面上看出来的。每一个传播行为,每一个传播者和接受者,都各自有一套目的和原因。但是,我们不能满足于那种解释。传播行为相似之处多于不同之处。人类传播起什么作用,理应得到更系统的解释。
出处:[美]施拉姆《MEN,WOMEN,MESSAGES,AND MEDIA:UNDERSTANDING HUMAN COMMUNICATION》第二章,17-21页.
第二篇:测绘专业英语论文外文翻译
The measurement of the surveying and mapping in mine Since the seventy s, as the electronic technology and laser technology development, the type of surveying and mapping instruments with electronics(such as range finder, electronic tachometer, gyroscopes)to the traditional surveying and mapping instruments methods produced profound effect.In satellite remote sensing, global positioning system, as a representative of the space on earth observation technology in surveying and mapping application in the science of mature, computer technology, system scientifically based geographic information system and application for the emergence of surveying and mapping information source of access, analyze, management, processing and application fully provide strong technical support, automation and intelligence of surveying and mapping system is already in investigation, therefore we can say, the modern mapping technology is undergoing a profound revolution.Mining of measuring technology of an important application field, in the vast coal, metal mines, nonferrous mine production process played an important role.Mine survey of modern task is: in mine exploration, design, development and production of the different stages of the operation of the ground and underground mining area, the space, resources,(in mineral and land resources and environment are mainly)information acquisition, storage, processing, display and use for reasonable and effective development resources, protecting the resources, protecting the environment, management, industrial and environmental services for the continuous development of the station.In order to realize its modern task, mine measurement must be making full use of modern surveying and mapping instruments and techniques, put the advanced modern technology with mine surveying the actual work, specific characteristics, and the combination of broaden the living space mine survey and business scope, promote the reform and development of mine survey, adapt to the market economy system and mining system reform needs.Electronic tachometer, space information technology, the inertial measurement system and other modern surveying and mapping instruments have been in mine survey technology is used to further development and are constantly.This paper to modern surveying and mapping instruments of the development of the technology and its application in mine.1、Electronic tachometer and its application in mine survey: Electronic tachometer as the most widely used surveying and mapping instruments, is electronic technology and optical technology development of the combination of the photoelectric measuring instrument, is also set range finder, electronic advantages in a wide range of instruments, application prospects, the intelligent electronic tachometer is currently the biggest selling surveying and mapping instruments, is also the main future development direction.Intelligent electronic tachometer is with light, electricity and magnetism, machine of the latest scientific achievements, set the location, measuring Angle for the integration of advanced instrument.The international advanced electronic tachometer are on a memory card, internal memory or electronic hand book way, way of double record data transmission communication function, can receive external computer instruction by the computer input data, also can to outside the computer output data.The international advanced electronic tachometer have Japanese SOKKIA POWERSET series production of electronic tachometer and SET5F, SET6F, SET5W electronic tachometer, Swiss produces the TCA100 and TCA1800 electronic tachometer, Japan NIKON DTM-A series of electronic tachometer, etc.Our country has just south of the surveying and mapping instruments company production NTS-200 series electronic tachometer.Electronic tachometer has set up a file in the engineering survey, mine surveying, cadastral etc a wide range of applications, its development and application is in rapid developing.Electronic tachometer because and has the advantages of transit and range finder, and provide measurement results in digital form, its simple operation, stable performance, data can be through the electronic hand book and the computer to carry on the advantages of communication in the mine in the measurement of a wide range of applications.The ground control survey, topographic, engineering surveying all available is, contact measurement, the measurement work can also be used inunderground i To as a representative of the intelligent, digital instrument is minesurveying instrument one of the development direction in the future.Based on theelectronic tachometer and the modern computer technology can establish a mine 3 d data to be automatic collection, transmission,processing of mine surveying dataprocessing system, instead of traditional hand book records, manual entry, detailed calculation of repetitive work.In addition, electronic tachometer in mine surfacemovement monitoring, land reclamation project implementation, mine construction aspects also have been applied, each big ore measurement organizations are to instead of traditional instruments for routine measure the work, not only improves the efficiency, picked up speed, and reduced the development, and to ensure the accuracy
2、Space information technology and its application in the measurement of the mine.The core of spatial information technology and the subject is the “3 S” technology(Remote Sensing:RS)、(Global Positioning System GPS)、(Grographic Information System:GIS)Remote sensing including satellite remote sensing and remote sensing, remote sensing data topographic map surveying as the important means in practice has a wide range of applications, satellite remote sensing for mapping is also mine of study and has made some significant results, based on remote sensing data to build digital terrain model(DTM)and then used in surveying and mapping work has won more applications.GPS as a cause of surveying and mapping in the traditional concept of major change technology, has become a main technology of land measurement method, also is the most potential mobile technology, in mine measurement, control survey, project survey, environment monitoring, disaster prevention and reduction of the navigation transport plays a significant role.Because not only have all-weather GPS, high precision and high flexibility, and the advantages of the traditional measuring technology without strict control, compared the level measurement, don't take points between depending on the point, without the need to build standard, there is no error accumulation, the three dimensional positioning etc, and in the field measurement model, error sources and data processing to the traditional concept of surveying and mapping is a revolutionary change.The geographic information system as the geographical distribution of space of therelevant data collecting, processing, management, analysis of computer technology system, and its development and application of surveying and mapping the development of science is of great significance, is the modern mapping technology of important technical support.With “3 S” integration or integrated as the leading technology of space information system has gradually become the surveying and mapping learning or the earth informatics new technology system and the work pattern, its advanced nature, timeliness obvious.With the space information technology for technical support, modern surveying and mapping instruments, technology is in rapid development in.The measurement of the remote sensing technology in the mines application has experienced a long time, and has accumulated rich experience.For remote sensing, it can be used as remote sensing data mining on the data topographic map surveying data source, like a piece of correction, through visual interpretation, field adjustable draw the work, complete the topographic map surveying and mapping.Compared with the traditional mapping method, using remote sensing data of mapping speed, low cost, high precision, it is a kind of application very extensive mapping method.Remote sensing in mine measurement of the applications of the key theory and technology also is in the investigation.Application of remote sensing data mining area, can obtain real-time, dynamic and comprehensive information source, to the mining area environment monitoring of the mining area environment protection to provide decision support.Remote sensing data mining area for prospecting, geological conditions, roof and floor of coal seam in such aspects as research has been applied, all these, explains the application of remote sensing technique in mining measurement is mine surveying realize its modern task important guarantee.GPS technology in the measurement of the mine is mainly applied to replace traditional ground surveying and mapping work.Using GPS technology such as mining surface movement monitoring, hydrology monitoring, mining area control elevation hole net establishment or measure, reform, GPS receiver with performance to price has been rising, and its application in the measurement of mine work the ground has become a part of the modern mine survey is an important support technology.Used in mining area the geographic information system is for mine geographical information system, or called mine material source environment alinformation system(MRIES).MREIS has become the important developing direction mine survey.With mining area environment resources information system as a platform to all kinds of measurement techniques for data acquisition approach, can build a collection of data acquisition, processing, management, analysis and output in one of the automation, intelligent technology system, as the sustainable development of mining decision support system.Mine survey MREIS work is to establish the fist work, and to create a MREIS mine surveying is an inevitable trend.Therefore, the GPS in the mining area is first applied used in a mine measurement information system established measurement, and then based on this establish the mining area environment information system resources.Space information technology is mine surveying realize its modern task of important technical support and guarantee, “3 S” technology and other measuring instrument technology on the basis of the organic combination of the mining area environment information system is the spatial data information technology in mine survey of the applications of the comprehensive results.3.the inertial measurement system and its application in the measurement of the mine The inertial measurement system(Inertial ISS)is a kind of navigation and positioning technology, have all-w, autonomous, fast can flexible and advantages, the earth measurement, engineering surveying and mining measure the work of automation and versatility provided another kind of new technology.It is to use the principle of inertial navigation, and earn geodetic data(longitude and latitude, elevation, azimuth, gravity anomaly and vertical deflection, etc.)of a kind of technology system.ISS can be divided into two categories: platform utility system and type system in the field of surveying and mapping, ISS main application target includes:(1)control measure, such as the existing control point review, encryption, and aerial control, etc.;(2)pipeline monitoring, orientation, crustal deformation, the surface subsidence observation;(3)underground positioning, all kinds of engineering and construction measure;(4)earthquake, gravity survey, geophysical research;(5)shaft and cans of vertical way beam of monitoring, etc.GPS/ISS combination system is to meet high precision navigation and positioning of the development direction of the request.This combination system can make the GPS and the performance of theISS, can get a lot of complementary to the whole land measurement model dataprocessing, and make sure that 3 d coordinate and the positioning and the precision of the navigation unstable, and increased significantly.The inertial measurement system in mine to the measurement of the Lord is applied in application in themeasurement of the application, the activities of the underground measurement, and of course the ground also has been applied in many fields, such as stated above.ISS in mines in China, the application in the measurement of work is to carry out in-depth,continue to develop.With GPS + ISS combination system used in mines measurement is a promising a technologyFour other new technology in the new instrument of surveying and mapping application to the measurement of the mineOther modern surveying and mapping instruments, such as laser point to meter, the gyro th, digital levels and related technology are all mine surveying and mapping measurement is used, and with the instrument technology as the foundation, formed many mining measurement instrument, as mine survey for the application of modern instruments and techniques.Mine survey as a cross subject, the development and the progress and the mining technology and the development of the mining project, measuring instruments and equipment of science and technology and the development of other subjects like mathematical science, computer science, etc, the development are closely related.Modern mapping technology is based on the electronic technology, space technology, optical technology, computer technology based on comprehensive technology, and has the intelligence, automation and so on a series of advantages.Modern science and technology, the rapid development of surveying and mapping can surely promote the further development of mine survey.With modern technology, mining engineering surveying and mapping technology and related science and technology as the foundation, the mine survey will form and collect data acquisition, processing, management, transmission, analysis, expression, application, output for the integration of intelligence, automation technology system for mine resources, environmental information system establishment provide fundamental material, promoting mine sustainable development.测绘在矿山测量中的发展
七十年代以来,随着电子技术和激光技术的发展,光电结合型的测绘仪器(如测距仪、全站仪、陀螺仪)对传统的测绘仪器方法产生了深刻的影响。以卫星遥感、全球定位系统为代表的空间对地观测技术在测绘科学中的应用日趋成熟,以计算机技术、系统科学为基础的地理信息系统的出现和应用为多源测绘信息的获取、分析、管理、处理及其充分应用提供了有力的技术支持,自动化、智能化的测绘系统已处于研究之中,因此可以说,现代测绘技术正在经历着一场深刻的革命。矿山测量技术的一个重要应用领域,在广大的煤矿、金属矿山、有色矿山等的生产过程中发挥着重要的作用。矿山测量的现代任务是:在矿山勘探、设计、开发和生产运营的各个阶段,对矿区地面和地下的空间、资源、(以矿产和土地资源为主)和环境信息进行采集、存储、处理、显示、利用,为合理、有效地开发资源、保护资源、保护环境、治理环境服务,为工矿区的持续发展报务。为了实现其现代任务,矿山测量必须充分应用现代测绘仪器和技术,将先进的现代技术同矿山测量的实际工作、具体特点相结合,拓宽矿山测量的生存空间和业务范围,促进矿山测量的改革和发展,适应市场经济体制和矿山体制改革的需要。全站仪、空间信息技术、惯性测量系统等现代测绘仪器技术均已在矿山测量中得到了应用并正在不断向纵深发展。为此本文对现代测绘仪器技术的发展及其在矿山测量的应用进行系统的分析和研究,以使矿山测量更好地服务于矿山可持续发展。
现代测绘仪器、技术及其在矿山测量中的应用: 1 全站仪及其在矿山测量中的应用:
全站仪作为当前应用最为广泛的测绘仪器,是电子技术与光学技术发展结合的光电测量仪器,也是集测距仪、电子经纬仪的优点于一体的、应用前途广泛的仪器,智能化的全站仪是目前销量最大的测绘仪器,也是今后发展的主要方向。智能型全站仪是集光、电、磁、机的最新科学成果,集测距、测角为一体的先进仪器。国际上先进的全站仪均以存储卡、内部存储器或电子手簿的方式记录数据,具有双路传输的通讯功能,能接收外部计算机的指令,由计算机输入数据,也能向外部计算机输出数据。目前国际上较先进的全站仪有日本SOKKIA生产的POWERSET系列全站仪及其SET5F、SET6F、SET5W全站仪,瑞士Leica公司生产的TCA100及TCA1800全站仪,日本NIKON的DTM-A系列全站仪等。我国目前仅有南方测绘仪器公司生产的NTS-200系列全站仪。全站仪已在工程测量、矿山测量、地籍测量等领域得到了广泛的应用,其发展及应用正处在飞速发展之中。全站仪由于兼具有经纬仪和测距仪的优点,且以数字形式提供测量成果,其操作简便、性能稳定、数据可通过电子手簿与计算机进行通讯等优点使其在矿山测量中得到了广泛的应用。地面控制测量、地形测量、工程测量均可利用全站仪进行,联系测量、井下测量工作也可用全站仪进行。以全站仪为代表的智能化、数字化仪器是矿山测量仪器今后的发展方向之一。基于全站仪和现代计算机技术可建立矿山三维数据自动采集、传输、处理的矿山测量数据处理系统,取代传统的手簿记录、手工录入、繁琐计算等大量的重复性的工作。此外,全站仪在矿山地表移动监测、矿区土地复垦工程实施、矿区施工等方面也都得到应用,各大矿的测量机构正在以全站仪取代传统的仪器进行日常的测量工作,既提高了效益,加快了速度,又减少了开发,保证了精度。空间信息技术及其在矿山测量中的应用:
空间信息技术的核心和主体是“3S”技术,即遥感(Remote Sensing:RS)、全球定位系统(Global Positioning System: GPS)、地理信息系统(Grographic Information System:GIS)。遥感包括卫星遥感和航空遥感,航空遥感作为地形图测绘的重要手段已在实践中得到了广泛的应用,卫星遥感用于测图也正在矿究之中并已取得一些意义重大的成果,基于遥感资料建立数字地面模型(DTM)进而应用于测绘工作已获得了较多的应用。GPS作为一项引起传统测绘观念重大变革的技术,已经成为大地测量的主要技术手段,也是最具潜力的全能型技术,在矿山测量、控制测量、工程测量、环境监测、防灾减灾以及交通运输工具的导航方面发挥着重要的作用。由于GPS不仅具有全天候、高精度和高度灵活性的优点,而且与传统的测量技术相比,无严格的控制测量等级之分,不必考虑测点间通视,不需造标,不存在误差积累,可同时进行三维定位等优点,在外业测量模式、误差来源和数据处理方面是对传统测绘观念的革命性转变。地理信息系统作为对空间地理分布有关的数据进行采集、处理、管理、分析的计算机技术系统,其发展和应用对测绘科学的发展意义重大,是现代测绘技术的重大技术支撑。以“3S”一体化或集成为主导的空间信息技术体系已逐渐成为测绘学或地球信息学(Geoinformatics或Geomatics)新的技术体系和工作模式,其先进性、时效性明显。以空间信息技术为技术支撑,现代测绘仪器、技术正处于快速的发展之中。遥感技术在矿山测量中的应用已经历了较长的时间,并积累了丰富的经验。对于航空遥感来说,航空遥感资料可作为进行矿区地形图测绘的资料源,通过象片校正、目视判读、野外调绘等工作,完成地形图的测绘。较之传统的测图方法,利用遥感资料进行测图速度快、成本低、精度高,是一种应用极为广泛的测图方法。航天遥感在矿山测量中应用的关键理论与技术也正处于研究之中。应用遥感资料,可获取矿区实时、动态、综合的信息源,对矿区环境进行监测,为矿区环境保护提供决策支持。遥感资料用于找矿、矿区地质条件研究、煤层顶底板研究等方面都已得到应用,所有这些,都说明遥感技术应用于矿山测量是矿山测量实现其现代任务的重要保证。GPS技术在矿山测量中的应用主要是取代传统的地面测绘工作。如利用GPS技术进行矿区地表移动监测、水文观测孔高程监测、矿区控制网建立或复测、改造等。随着GPS接收机性能价格比的不断上升,其应用于矿山测量工作的地面部分已成为现代矿山测量的一项重要支撑技术。应用于矿区的地理信息系统即为矿区地理信息系统,或称为矿区资料源环境信息系统(MRIES)。MREIS已成为矿山测量的重要发展方向。以矿区资源环境信息系统为平台,以各种测量技术为数据获取的途径,可以建立集数据采集、处理、管理、分析、输出于一体的自动化、智能化的技术系统,作为矿山可持续发展的决策支持系统。矿山测量工作是建立MREIS的前提性工作,而建立MREIS则是矿山测量发展的必然趋势。因此,GPS在矿区应用首先就是应用于矿山测量建立矿山测量信息系统,然后以此为基础建立矿区资源环境信息系统。空间信息技术是矿山测量实现其现代任务的重要的技术支撑和保证,以“3S”技术和其他测量仪器技术的有机结合为基础的矿区资料环境信息系统就是空间信息技术在矿山测量中应用的综合性成果。惯性测量系统及其在矿山测量中的应用:
惯性测量系统(Inertial Surveying System: ISS)是一种导航定位技术,具有全天候、自主式、快速多能和机动灵活等优点,为大地测量、工程测量和矿山测量作业的自动化和全能性提供了另一种新的技术手段。它是利用惯性导航的原理,以同时获取多种大地测量数据(经纬度、高程、方位角、重力异常和垂线偏差等)的一种技术系统。ISS可分为两大类:平台式系统和捷联式系统,ISS在测绘领域的主要应用目标包括:(1)控制测量,如对已有控制点的检核、加密、航测控制等;(2)管线监测、定位、地壳形变、地表沉陷观测;(3)井下定位,各种工程和建筑测量;(4)地震、重力测量,地球物理研究;(5)井筒和罐道梁的垂直性监测等。GPS/ISS组合系统是满足高精度导航和定位要求的发展方向之一。这种组合系统可使GPS与ISS的性能得到很多互补,能够以整体大地测量模型进行数据处理,同时确定三维坐标和大地水准面,使定位和导航的精度稳定,且显著提高。惯性测量系统在矿山测量中的应用主是在矿山井下测量中的应用,进行井下测量的各项工作,当然其在地面也有广泛的应用领域,如前文所述。ISS在我国矿山测量中应用的工作尚未深入开展,有待继续发展。以GPS+ISS组合系统应用于矿山测量则是较有发展前途的一项技术 4 其他测绘新仪器新技术在矿山测量中的应用:
其他的现代测绘仪器如激光指向仪、陀螺经纬仪、数字式水准仪及相关的测绘技术等都在矿山测量中得到了应用,并以这些仪器技术为基础,形成了许多矿山测量的专用仪器,作为矿山测量应用的现代仪器和技术。结论:
矿山测量作为一门交叉性学科,其发展和进步与采矿技术和矿业工程的发展、测量科学技术与仪器设备的发展、其它学科如数理科学、计算机科学等的发展密切相关。现代测绘技术是建立在电子技术、空间技术、光学技术、计算机技术等基础上的综合性技术,并具有智能化、自动化等一系列优点。现代测绘科学技术迅猛发展,必然会促进矿山测量的进一步发展。以现代测绘技术、矿业工程技术和相关科学技术为基础的矿山测量,必将会形成集数据采集、处理、管理、传输、分析、表达、应用、输出为一体的智能化、自动化的技术系统,为矿区资源环境信息系统的建立提供基础性的资料,促进矿山可持续发展。
第三篇:外文翻译
当今时代是一个自动化时代,交通灯控制等很多行业的设备都与计算机密切相关。因此,一个好的交通灯控制系统,将给道路拥挤,违章控制等方面给予技术革新。随着大规模集成电路及计算机技术的迅速发展,以及人工智能在控制技术方面的广泛运用,智能设备有了很大的发展,是现代科技发展的主流方向。本文介绍了一个智能交通的系统的设计。该智能交通灯控制系统可以实现的功能有:对某市区的四个主要交通路口进行控制:个路口有固定的工作周期,并且在道路拥挤时中控制中心能改变其周期:对路口违章的机动车能够即时拍照,并提取车牌号。在世界范围内,一个以微电子技术,计算机和通信技术为先导的,一信息技术和信息产业为中心的信息革命方兴未艾。而计算机技术怎样 与实际应用更有效的结合并有效的发挥其作用是科学界最热门的话题,也是当今计算机应用中空前活跃的领域。本文主要从单片机的应用上来实现十字路口交通灯智能化的管理,用以控制过往车辆的正常运作。
研究交通的目的是为了优化运输,人流以及货流。由于道路使用者的不断增加,现有资源和基础设施有限,智能交通控制将成为一个非常重要的课题。但是,智能交通控制的应用还存在局限性。例如避免交通拥堵被认为是对环境和经济都有利的,但改善交通流也可能导致需求增加。交通仿真有几个不同的模型。在研究中,我们着重于微观模型,该模型能模仿单独车辆的行为,从而模仿动态的车辆组。
由于低效率的交通控制,汽车在城市交通中都经历过长时间的行进。采用先进的传感器和智能优化算法来优化交通灯控制系统,将会是非常有益的。优化交通灯开关,增加道路容量和流量,可以防止交通堵塞,交通信号灯控制是一个复杂的优化问题和几种智能算法的融合,如模糊逻辑,进化算法,和聚类算法已经在使用,试图解决这一问题,本文提出一种基于多代理聚类算法控制交通信号灯。
在我们的方法中,聚类算法与道路使用者的价值函数是用来确定每个交通灯的最优决策的,这项决定是基于所有道路使用者站在交通路口累积投票,通过估计每辆车的好处(或收益)来确定绿灯时间增益值与总时间是有差异的,它希望在它往返的时候等待,如果灯是红色,或者灯是绿色。等待,直到车辆到达目的地,通过有聚类算法的基础设施,最后经过监测车的监测。
我们对自己的聚类算法模型和其它使用绿灯模拟器的系统做了比较。绿灯模拟器是一个交通模拟器,监控交通流量统计,如平均等待时间,并测试不同的交通灯控制器。结果表明,在拥挤的交通条件下,聚类控制器性能优于其它所有测试的非自适应控制器,我们也测试理论上的平均等待时间,用以选择车辆通过市区的道路,并表明,道路使用者采用合作学习的方法可避免交通瓶颈。
本文安排如下:第2部分叙述如何建立交通模型,预测交通情况和控制交通。第3部分是就相关问题得出结论。第4部分说明了现在正在进一步研究的事实,并介绍了我们的新思想。
The times is a automation times nowadays,traffic light waits for much the industey equipment to go hand in hand with the computer under the control of.Therefore,a good traffic light controls system,will give road aspect such as being crowded,controlling against rules to give a technical improvement.With the fact that the large-scale integrated circuit and the computer art promptness develop,as well as artificial intelligence broad in the field of control technique applies,intelligence equipment has had very big development,the main current being that modern science and technology develops direction.The main body of a book is designed having introduccd a intelligence traffic light systematically.The function being intelligence traffic light navar’s turn to be able to come true has:The crossing carries out supervisory control on four main traffic of some downtown area;Every crossing has the fixed duty period,charges centrefor being able to change it’s period and in depending on a road when being crowded;The motro vehicle breaking rules and regulations to the crossing is able to take a photo immediately,abstracts and the vehicle shop sign.Within world range ,one uses the microelectronics technology,the computer and the technology communicating by letter are a guide’s,centering on IT and IT industry information revolution is in the ascendant.But,how,computer art applies more effective union and there is an effect’s brought it’s effect into play with reality is the most popular topic of scientific community,is also that computer applications is hit by the unparalleled active field nowadays.The main body of a book is applied up mainly from slicing machine’s only realizing intellectualized administration of crossroads traffic light,use operation in controlling the vehicular traffic regularity.Transportation research has the goal to optimize transportation flow of people and goods.As the number of road users constantly increases, and resources provided by current infras-tructures are limited, intelligent control of traffic will become a very important issue in thefuture.However, some limitations to the usage of intelligent tra?c control exist.Avoidingtraffic jams for example is thought to be beneficial to both environment and economy, butimproved traffic-flow may also lead to an increase in demand [Levinson, 2003].There are several models for traffic simulation.In our research we focus on microscopicmodels that model the behavior of individual vehicles, and thereby can simulate dynam-ics of groups of vehicles.Research has shown that such models yield realistic behavior[Nagel and Schreckenberg, 1992, Wahle and Schreckenberg, 2001].Cars in urban traffic can experience long travel times due to inefficient traffic light con-trol.Optimal control of traffic lights using sophisticated sensors and intelligent optimizationalgorithms might therefore bevery beneficial.Optimization of traffic light switching increasesroad capacity and traffic flow, and can prevent tra?c congestions.Traffic light control is acomplex optimization problem and several intelligent algorithms, such as fuzzy logic, evo-lutionary algorithms, and reinforcement learning(RL)have already been used in attemptsto solve it.In this paper we describe a model-based, multi-agent reinforcement learningalgorithm for controlling traffic lights.In our approach, reinforcement learning [Sutton and Barto, 1998, Kaelbling et al., 1996]with road-user-based value functions [Wiering, 2000] is used to determine optimal decisionsfor each traffic light.The decision is based on a cumulative vote of all road users standingfor a traffic junction, where each car votes using its estimated advantage(or gain)of settingits light to green.The gain-value is the difference between the total time it expects to waitduring the rest of its trip if the light for which it is currently standing is red, and if it is green.The waiting time until cars arrive at their destination is estimated by monitoring cars flowingthrough the infrastructure and using reinforcement learning(RL)algorithms.We compare the performance of our model-based RL method to that of other controllersusing the Green Light District simulator(GLD).GLD is a traffic simulator that allows usto design arbitrary infrastructures and traffic patterns, monitor traffic flow statistics such asaverage waiting times, and test different traffic light controllers.The experimental resultsshow that in crowded traffic, the RL controllers outperform all other tested non-adaptivecontrollers.We also test the use of the learned average waiting times for choosing routes of cars through the city(co-learning), and show that by using co-learning road users can avoidbottlenecks.
第四篇:外文翻译
设计一个位于十字路口的智能交通灯控制系统
摘要:本文模型使用模糊本体的交通灯控制域,并把它应用到控制孤立十字路口。本文最重要的目的之一是提出一个独立的可重复使用的交通灯控制模块。通过这种方式,增加软件的独立性和为其他的软件开发活动如测试和维护,提供了便利。专家对本体论进行手动的开发和评估。此外,交通数据提取和分类路口使用的人工神经网络的图像处理算法。根据预定义的XML架构,这种信息转化为XML实例映射到适合使用模糊推理引擎的模糊规则的模糊本体。把本系统的性能与其他类似的系统性能进行比较。比较结果显示:在所有的交通条件下,在每个周期中,对每辆车它有低得多的平均延迟时间与其他的控制系统相比。
关键词:模糊本体,智能代理,智能交通系统(ITS),交通信号灯控制(TLC),孤立的十字路口,图像处理,人工神经网络
1.引言
作为城市交通增加的结果,道路网络的能力有限和发展交通工具和方法的技术方面,许多实体,关系,情况和规则已经进入交通灯控制域和转化成为一个知识领域。这个领域的建模知识帮助交通代理和应用有效地管理关于实时条件下的交通。全面知识建模领域的一个最合适的方法是使用本体概念。“本体论是一个正式的、明确的一个共享的概念化的规范。以前的模型是基本的本体建设的基础,为下列建立一个共享的语义丰富的知识域。除了本体作为概念化的形式主义的重要性,它有可能超过所代表的数据。这种能力将提高有关性能的决定和其他非智能系统的功能特点。在近年来,本体论上的研究正成为一个新的热点话题在不同的活动,如人工智能,知识管理,语义网络,电子商务和几个其他应用领域。这些领域之一是智能交通系统。一些努力已制成这个通过展示和使用本体检测交通领域拥塞,管理非城市道路气象事件,驾驶阿德福—索里系统,共享和整合一个智能交通系统。本文的目的是介绍一个红绿灯有效控制孤立交叉口这方面的知识重用的控制本体。这种新的办法适用于智能代理使用知识决策模糊。该系统采用的图像来自安装了监控摄像机拍摄的路口。这些图像处理利用图像处理算法和神经网络的方法,然后发送到一个智能代理。第2节中,我们将简要地解释了在这项工作中运用的技术包括seman-TIC网络技术,智能代理技术和交通的回地面光控制方法。在第3节,新的系统架构是基于分层语义网络架构。第4节介绍交通灯控制的模糊本体的建设。第五节从路口提取的图像信息解释。在第6节,智能系统的运作被完整描述,最后在第7节对所提出的方法进行评估,对结论进行阐述。
2.背景
本节说明在这项工作中的应用技术包括语义网络技术,特别本体和模糊本体。此外,国家的交通灯控制的艺术方法是简要介绍。2.1.语义网络技术
语义网络被定义为当前Wed的延伸,这些网站的信息都给出明确的含义;使电脑与人更好的合作。有几层语义Web的建议源自伯纳斯滞后阶段。在此类别中的所有规则如表1所示。图.4显示输出模式的示意图。本次评选有助于智能系统,以确定下一步的阶段测序。
另一种模糊的规则类别涉及估计优化周期时间。这些规则的模糊变量是天气条件,时间,每天平均车辆拥堵情况。出于这个原因,60个模糊规则被定义了。从气象研究所取得气象条件。日期和时间也是在交通专家的知识的基础上以模糊变量形式预先定义的。图5显示日期,时间和周期时间的隶属函数。当天的参数是在日历基础上基于假期和正常的一天与周期时间量的关系预定义的。例如,假期期间的周期时间是较平日少。因此,平日的隶属度比假期多。
例如一个阶段选型的模糊规则如下所述:“如果一个路口的类型是四的方式,平均车辆拥堵低,平均行人拥堵是中等,然后相类型是简单的两阶段”。此外,为周期时间估计的模糊规则表示如下:“如果天气条件是晴天,时间是早晨,天是正常的,平均车辆拥堵是低,则周期时间短”。在此类别中的所有规则都列在附录A。
在此步骤结束时,应该对交通灯逻辑控制的项目的有效性进行评估。此功能是使用专家的意见。评价过程的主要目的是显示发展的本体和其相关的软件环境的用处。虽然所有的信息,尤其是交通灯控制规则已提取国际标准和科学交通文学,专家的知识优势是他们最后的正确性验证标准。所有模糊规则,包括优化周期时间和相位类型的规则,在这个过程中,准备以调查问卷形式和展现给一些专家包括从德黑兰警察局交通上校和两名来自德黑兰的交通组织工程师。由于德尔菲专家的意见,约有84%的淘汰型规则和优化周期时间的87%被接受。此外,所有交通逻辑控制的元素包括概念,关系,属性和公理都被这些专家进行了评估和验证。我们评估逻辑交通控制是基于理论知识的。在这个过程中进行了两项活动,包括检查的要求和能力的问题,并在目标应用环境测试本体。由于逻辑交通控制已建成的基础上,如指定要求优化循环时间,逐步淘汰型,交通的移动和优化绿灯时间,每个阶段的序列中,第一项活动是最好的结果。逻辑交通控制满足所有的交通灯控制的需求,并能回答的能力问题。绩效评估机制,可以支持这种说法。在部分实验结果我们验证了这一过程。
第五篇:外文翻译
中原工学院毕业设计(论文)译文
超声测距系统设计
原文出处:传感器文摘 布拉福德:1993年第13页
摘要:超声测距系统技校在工业场车辆导航水声工程等领域都具有了广泛的应用价值,目前已应用于物理测量,机器人自动导航以及空气中与水下的目标探测、识别定位等场合,因此,深入研究超声的探测理论和方法具有重要的实践意义,为了进一步提高测量的精确度,满足工程人员对测量精度测距量程和测距仪使用的要求,本文研制了一套基于单片机的使拱式超声测距系统。关键词:超声波 测距仪 单片机
1、前言
随着科技的发展,人们生活水平的提高,城市发展建设加快,城市给排水系统也有较大发展,其状况不断改善,但是,由于历史原因合成时间性的许多不可预见因素,城市给排水系统,特别是排水系统往往落后于城市建设,因此,经常出现开挖已经建设好的建筑设施来改造排水系统的现象。城市污水给人们带来的困扰,因此箱的排污疏通对大城市给排水系统污水理,人们生活舒适显得非常重要。而设计研制箱涵排水疏通移动机器人的自动控制系统,保证机器人在箱涵中自由排污疏通,是箱涵排水系统疏通机器人的设计研制的核心部分,控制系统核心部分就是超声波测仪的研制。因此,设计好的超声波测距仪就显得非常重要了。
1.1课题背景
随着经济的发展与汽车科学技术的进步,公路交通呈现出行驶高速化、车流密集化和驾驶员非职业化的趋势。同时,随着汽车工业的飞速发展,汽车的产量和保有量都在急剧增加。但公路发展、交通管理却相对落后,导致了交通事故与日剧增,城市里尤其突出。智能交通系统ITS是目前世界上交通运输科学技术的前沿技术,它在充分发挥现有基础设施的潜力,提高运输效率,保障交通安全,缓解交通赌塞,改善城市环境等方面的卓越效能,已得到各国政府的广泛关注。中国政府也高度重视智能交通系统的研究开发与推广应用。汽车防撞系统作为ITS 发展的一个基础,它的成功与否对整个系统有着很大的作用。从传统上说,汽车的安全可以分为两个主要研究方向:一是主动式安全技术,即防止事故的发生,该种方式是目前汽车安全研究的最终目的;二是被动式安全技术,即事故发生后的乘员保护。目前汽车安全领域被动安全研究较多,主要从安全气囊、ABS(防抱死系统)和悬架等方面着手,以保证驾乘人员的安全。从经济性和安全性两方面来说,中原工学院毕业设计(论文)译文
这些被动安全措施是在事故发生时刻对车辆和人员进行保护,有很大的局限性,因而车辆的主动安全研究尤为重要,引出了本文研究的基于单片机的超声波测距系统。这个系统是一种可向司机预先发出视听语音信号的探测装置。它安装在汽车上,能探测企图接近车身的行人、车辆或周围障碍物;能向司机及乘员提前发出即将发生撞车危险的信号,促使司机采取应急措施来应付特殊险情,避免损失。
1.2 课题设计的意义
随着现代社会工业化程的发展,汽车这一交通工具正为越来越多的人所用,但是随之而来的问题也显而易见,那就是随着车辆的增多,交通事故的频繁发生,由此导致的人员伤亡和财产损失数目惊人。对于公路交通事故的分析表明,80%以上的车祸事由于驾驶员反应不及所引起的,超过65%的车辆相撞属于追尾相撞,其余则属于侧面相撞。奔驰汽车公司对各类交通事故的研究表明:若驾驶员能够提早1S 意识到有事故危险并采取相应的正确措施,则绝大多数的交通事故都可以避免。因此,大力研究开发如汽车防撞装置等主动式汽车辅助安全装置,减少驾驶员的负担和判断错误,对于提高交通安全将起到重要的作用。显然,此类产品的研究开发具有极大的实现意义和广阔的应用前景。
1.3超声波测距在汽车上应用的介绍
超声波倒车测距仪(俗称电子眼)是汽车倒车防撞安全辅助装置,能以声音或者更为直观的数字形式动态显示周围障碍物的情况。其较早的产品是用蜂鸣器报警,蜂鸣声越急,表示车辆离障碍物越近。后继的产品可以显示车后障碍物离车体的距离。其大多数产品探测范围在0.4~1.5m,有的产品能达到0.35~2.5m,并有距离显示、声响报警、区域警示和方位指示,有些产品还具备开机自检功能。目前市场上还出现了具有语音报警功能的产品。这些产品存在的主要问题是测量盲区大,报警滞后,未考虑汽车制动时的惯性因素,使驾驶者制动滞后,抗干扰能力不强,误报也较多。汽车防撞雷达之所以能实现防撞报警功能,主要有超声波这把无形尺子, 它测量最近障碍物的距离, 并告诉给车主。其实超声测距原理简单: 它发射超声波并接收反射回波, 通过单片机计数器获得两者时间差t, 利用公式S=Ct/2计算距离, 其中S为汽车与障碍物之间的距离, C为声波在介质中的传播速度。
本文介绍的超声测距系统共有2只超声波换能器(俗称探头),分别布置在汽车的后左、后右2个位置上。能检测前进和倒车方向障碍物距离, 通过后视镜内置的
中原工学院毕业设计(论文)译文
显示单元显示距离和方位, 发出一定的声响, 起到提示和警戒的作用。系统采用一片STC89C52单片机对两路超声波信号进行循环采集。超声波是指频率高于20HHZ的机械波。为了以超声波作为检测手段,必须产生超生波和接收超声波。完成这种功能的装置就是超声波传感器,习惯上称为超声波换能器或超声波探头。超声波传感器有发送器和接收器,但一个超声波传感器也可具有发送和接收声波的双重作用。超声波传感器是利用压电效应的原理将电能和超声波相互转化,即在发射超声波的时候,将电能转换,发射超声波;而在收到回波的时候,则将超声振动转换成电信号。超声波测距的原理一般采用渡越时间法。首先测出超声波从发射到遇到障碍物返回所经历的时间,再乘以超声波的速度就得到二倍的声源与障碍物之间的距离。测量距离的方法有很多种,短距离的可以用尺,远距离的有激光测距等,超声波测距适用于高精度的中长距离测量。因为超声波在标准空气中的传播速度为331.45米/秒,由单片机负责计时,单片机使用12.0M晶振,所以此系统的测量精度理论上可以达到毫米级。由于超声波指向性强,能量消耗缓慢,在介质中传播距离远,因而超声波可以用于距离的测量。利用超声波检测距离,设计比较方便,计算处理也较简单,并且在测量精度方面也能达到要求。超声波发生器可以分为两类:一类是用电气方式产生超声波,一类是用机械方式产生超声波。本设计属于近距离测量,可以采用常用的压电式超声波换能器来实现触发单元。
利用超声波测距的工作,就可以根据测量发射波与反射波之间的时间间隔,从而达到测量距离的作用。其主要有三种测距方法:
(1)相位检测法,相位检测法虽然精度高,但检测范围有限;
(2)声波幅值检测法,声波幅值检测法易受反射波的影响;
(3)渡越时间检测法,渡越时间检测法的工作方式简单,直观,在硬件控制和软件设计上都非常容易实现。其原理为:检测从发射传感器发射超声波,经气体介质传播到接收传感器的时间,这个时间就是渡越时间。本设计的超声波测距就是使用了渡越时间检测法。在移动车辆中应用的超声波传感器,是利用超声波在空气中的定向传播和固体反射特性(纵波),通过接收自身发射的超声波反射信号,根据超声波发出及回波接收的时间差和传播速度,计算传播距离,从而得到障碍物到车辆的距离。
中原工学院毕业设计(论文)译文 超声波测距原理
2.1 压电式超声波发生器原理
压电式超声波发生器实际上是利用压电晶体的谐振来工作的。超声波发生器内部结构,它有两个压电晶片和一个共振板。当它的两极外加脉冲信号,其频率等于压电晶片的固有振荡频率时,压电晶片将会发生共振,并带动共振板振动,便产生超声波。反之,如果两极板间未加电压,当共振板接收到超声波时,将压迫压电晶片做振动,将机械能转换为电信号,这是它就成为超声波接收器了。
测量脉冲到达时间的传统方法是以拥有固定参数的接收信号开端为基础的。这个信号恰恰选于噪音水平之上,然而脉冲到达时间被定义为脉冲信号刚好超过界限的第一时刻。一个物体的脉冲强度很大程度上取决于这个物体的自然属性尺寸还有它与传感器的距离。进一步说,从脉冲起始点到刚好超过界限之间的时间段随着脉冲的强度而改变。结果,一种错误便出现了——两个拥有不同强度的脉冲在不同时间超过界限却在同一时刻到达。强度较强的脉冲会比强度较弱的脉冲超过界限的时间早点,因此我们会认为强度较强的脉冲属于较近的物体。
2.2 超声波测距原理
超声波发射器向某一方向发射超声波,在发射时刻的同时开始计时,超声波在空气中传播,途中碰到障碍物就立即返回来,超声波接收器收到反射波就立即停止计时。超声波在空气中的传播速度为340m/s,根据计时器记录的时间t,就可以计算出发射点距离障碍物的距离(s),即:s=340t/2
中原工学院毕业设计(论文)译文
3、超声波测距系统的电路设计
系统的特点是利用单片机控制超声波的发射和超声波自发射至接受往返时间的计时,单片机选用C51,经济易用,且片内有4K的ROM,便于编程。电路的原理如图1所示。
图1 电路原理图
中原工学院毕业设计(论文)译文
3.1 40kHz脉冲的产生与超声波发射
测距系统中的超声波传感器采用UCM40的压电陶瓷,它的工作电压是40kHz的脉冲信号,这由单片机执行下面的程序来产生。puzel:mov 14h,#12h
here: cp1.0;
nop;
nop;
nop;
djnz 14h,here;
Ret
前方测距电路的输出端接单片机P1.0端口,单片机执行上面的程序后,在P1.0端口输出一个40khz的脉冲信号,经过三极管T放大,驱动超声波发射头UCM40T,发出40khz的脉冲超声波,且持续发射200ms。右侧合作侧测距电路的输入端分别接P1.1和P1.2端口,工作原理和前方测距电路相同。
超声波发射持续200ms 输出40kHz方波
3.2 超声波的接收与处理
接收头采用与发射头配对的UCM40R,将超声波调制脉冲变为电压信号,经运算放大器ic1a和ic1b两级放大后加至IC2,。IC2是带有锁定环的音频译码集成块LM567,内部压控振荡器的中心频率f0=1/1.1R8C3,电容C4决定其带宽。调节R8在发射的载频上,则LM567输入信号大于25mv,输出端8脚由5由高电平跃变为低电平,作为中断请求信号,送至单片机处理。
前方测距电路的输出端接至单片机INT0端口,中断优先级最高,左、右测距电路的输出通过与门IC3A的输出接单片机的INT1端口,同时单片机P1.3和P1.4接到IC3A的输入端,中断源的识别由程序查询来处理,中断优先级为先右后左。部分源程序如下: receive1:push psw
push acc
clr ex1;关中断源1
jnb p1.1,right;P1.1引脚为0,转至右侧距电路中断服务程序
jnb p1.2,left;P1.2 引脚为0,转至左测距中断电路服务程序 returne:SETB EX1;
开外部中断1
pop acc
中原工学院毕业设计(论文)译文
pop psw
reti right:
...;
右测距电路中断服务程序入口
ajmp return
left:
...;
左测距电路中断服务程序入口
ajmp return
3.3 计算超声波传播时间
在启动发射电路的同时启动单片机内部的定时器T0,利用定时器的计数功能,记录超声波发射的时间和受到反射波的时间。当收到超声波反射波时,接受电路输出端产生一个负跳变,在INT0或INT1端产生一个中断请求信号,单片机响应外部中断请求,执行外部中断服务子程序,读取时间差,计算距离。其部分源程序如下:
RECEIVEO: PUSH PSW
PUSH ACC CLR EX0;
关外部中断0 读取时间值
MOV R7,TH0;MOV R6,TL0 CLR C MOV A,R6 SUBB A,#0BBH;MOV 31H,A;MOV A,R7 SUBB A,#3CH MOV 30H,A SETB EX0;POP ACC
POP PSW
RETI 对于一个平坦的目标,测量距离包括两个阶段:粗糙的测量和精细的测量。第一步:脉冲的传送产生一种简单的超声波
第二步:根据公式改变回波放大器的获得量直到回拨被检测到。第三步:检测两种回波的振幅与过零时间。
计算时间值 存储结果
开外部中断0
中原工学院毕业设计(论文)译文
第四步:设置回波放大器的所得规格输出,假定是3v。通过脉冲的周期设置下一个脉冲。根据第二部的数据设定时间窗。
第五步:发射两窜脉冲产生干扰波。测量过零时间与回波振幅。如果逆向发生在回波中,决定要不通过在低气压插入振幅。
第六步:通过公式计算距离y。
中原工学院毕业设计(论文)译文
4、超声波测距系统的软件设计
软件分为俩部分,主程序和中断服务程序。主程序完成初始化工作、各路超声波发射和接收顺序的控制。定时中断服务子程序完成三方向超声波的轮流发射,外部中断服务子程序主要完成时间值的读取、距离计算、结果的输出等工作。
中原工学院毕业设计(论文)译文
5、结论
对所要求测量范围30cm-200cm内的平面物体做了多次测量发现,其最大误差为1.5cm,且重复性好。可见基于单片机设计的超声波测距系统具有硬件结构简单、工作可靠、测量误差小等特点。因此,它不仅可用于移动机器人,还可以用在其他检测系统中。
思考:至于为什么不用接收管做放大电路,因为放大倍数搞不好,集成放大电路,还带自动电平增益控制,放大倍数为76db,中心频率是38k到40k,刚好是超声波传感器的谐振频率。
中原工学院毕业设计(论文)译文
参考文献
1.Fox,J.D.,Khuri-Yakub,B.T.and Kino,G.S.,“High Frequency Acoustic Wave Measurement in Air”,in Proceedings of IEEE 1983 Ultrasonic Symposium,October 31-2 November,1983,Atlanta,GA,pp.581-4.2.Martin Abreu,J.M.,Ceres,R.And Freire,T.,“Ultrasonic Ranging: Envelope Analysis Gives Improved Accuracy”,Sensor Review, Vol.12 No.1,1992,pp.17-21.3.Parrilla, M., Anaya,J.J and Fritsch C.,‖Digital Signal Processing Techniques for High Accuracy Ultrasonic Range Measurement:,IEEE Transactions: Instrumentation and Measurement.Vol.40 No.4, August 1991,pp.750-63.4.Canali, C., Cicco, G.D., Mortem, B., Prudenziati, M., and Taron, A., ―A Temperature Compensated Ultrasonic Sensor Operating in Air for Distance and Proxinmity Measurement‖, IEEE Trasaction on Industry Electronics, Vol, IE-29 No.4,1982, pp.336-41.5.Martin, J.M., Ceres, R., Calderon, L and Freire, T., ‖Ultrasonic Ranging Gets Themal Correction‖, Sensor Review, Vol, 9 No.3, 1989,pp.153-5.中原工学院毕业设计(论文)译文
Ultrasonic ranging system design Publication title: Sensor Review.Bradford:1993.Vol.13 ABSTRACT: Ultrasonic ranging technology has wide using worth in many field, such as the industrial locale, vehicle navigation and sonar engineering.Now it has been used in level measurement, self-guided autonomous vehicles, fieldwork robots automotive navigation, air and underwater target detection, identification ,location and so on.So there is an important practicing meaning to learn the ranging theory and ways deeply.To improve the precision of the ultrasonic ranging system in hand, satisfy the request of the engineering personal for the precision,the bound and the usage, a portable ultrasonic ranging system based on the single chip processor was developed.Keywords: Ultrasound r, Ranging System, Single Chip Processor
1.Introductive With the development of science and technology, the improvement of people’s standard of living, speeding up the development and construction of the city.Urban drainage system have greatly developed their situation is constantly improving.However, due to historical reasons many unpredictable factors in the synthesis of her time, the city drainage system.In particular drainage system often lags behind urban construction.Therefore, there are often good building excavation has been building facilities to upgrade the drainage system phenomenon.It brought to the city sewage, and it is clear to the city sewage and drainage culvert in the sewage treatment system.Confort is very important to people’s lives.Mobile robots designed to clear the drainage culvert and the automatic control system Free sewage culvert clear guarantee robot, the robot is designed to clear the culvert sewage to the core.Control System is the core component of the development of ultrasonic range finder.Therefore, it is very important to design a good ultrasonic range finder.1.1 subject background
With the development of economy and car scientific and technological progress, highway traffic presents driving fast pace, traffic dense is changed and the driver not professional trend.At the same time, along with the rapid development of auto industry, automobile yield and quantities are increased dramatically.But road development,中原工学院毕业设计(论文)译文
transportation management is relatively backward, leading to a large number of traffic accidents in some cities, especially prominent.Intelligent transportation system in the world, ITS transportation science and technology of advanced technology, ITS exerting existing infrastructure of potential, enhance the transport efficiency, safeguard traffic safety and ease traffic wager plug, improving urban environment aspects of outstanding performance, has received the governments of widespread concern.The Chinese government is also highly intelligent transportation system of the development and popularization applications.The automotive anti-collision system as ITS development of a base, ITS success to the whole system has a very significant role.Traditionally, auto safety said can be divided into two main research direction: first,it is active safety technology, including the prevention of accidents, the way is now automotive safety research ultimate purpose;second, it is passive safety technique, namely the occupant protection after the accident.Now automotive safety field passive safety more research, mainly from the airbag, ABS(antilock brakes)and suspension from the aspects such as to ensure safety of personnel rides.From the economic and safety two ways, these passive safety measures is the accident of vehicle and personnel moments protection, with great limitations, thus vehicle active safety research is particularly important, leads to a of this study is based on single chip ultrasonic ranging system.This system is a kind of can advance to the driver issued audio-visual speech signal detection devices.It is installed in cars that can detect trying to approach the body of a car pedestrians and vehicles or around obstacles, Can send to the driver and crew imminent danger ahead of the signal, prompting a crash drivers take emergency measures to cope with special danger, avoid the loss.1.2 question design significance
Along with the development of modern society industrialization process, car this traffic tools are used for more and more people, but any problem has obvious that along with the increase in vehicles, traffic accident, which led to the frequent occurrence of casualties and property losses number astonishing.For highway traffic accident analysis showed that more than 80% of the accident due to the driver reaction inferior things, caused more than 65% of vehicle collision, the rest belongs to tracing cauda collided belongs to the side collision.Mercedes-benz Automobile Company for all kinds of traffic accident research shows that: if the driver can early 1S are aware
中原工学院毕业设计(论文)译文
that a accident risk and take the appropriate corrective measures, the overwhelming majority of traffic accidents can be avoided.Therefore, vigorously research and development as the automotive anti-collision device etc active car auxiliary safe device, reduce the burden and misjudgments drivers to improve the traffic safety will play an important role.Obviously, this kind of product research and development has great realize meaning and broad application prospects.1.3 Ultrasonic ranging in automotive applications introduced
Ultrasonic back-draft rangefinder(known as electron optics)automotive anti-collision reversing device, can safe adjunct to sound or more intuitive digital form the dynamic display of around obstacles.Its earlier products is to use buzzer alarm, hum more anxious, and says vehicles from obstructions closer.Subsequent product can display the car from the body after the obstacles distance.Most of its products detection range in 0.4 ~ 1.5 m, some product can achieve 0.35 ~ 2.5 m, and have distance display, sound alarm, area-warning and azimuth instructions, some products also has the boot self-checking function.Still appeared on the market at present with voice alarm function of products.These products are the main problem is big, alarm measuring blind area lags behind, without considering the automobile braking inertial factors and make drivers brake lag, the anti-interference ability is not strong, misstatement or more.The automotive anti-collision radar is able to realize impact-proof alarm functions, basically have ultrasonic this intangible ruler, it recently obstacles distance measurement, and told to the owner.Actually ultrasonic range-finding principle simple: it emit ultrasonic echo, and receive reflected by microcontroller counter obtain both lag using formula S = t, Ct / 2 calculating distances, including S for cars and obstacles, C for the distance between the sound wave propagation in the medium speed.This paper introduces the ultrasonic ranging system only have 2 ultrasonic transducer(known as probe)respectively, decorate in cars left and right after after 2 position.Capable of detecting forward and reverse direction obstacle distance, the rearview mirror built-in display element display distance and direction, issued must be sound, plays the role of hints and alert.System USES a STC89C52 SCM two way ultrasonic signal cyclicly acquisition.Ultrasonic refers to the 20HHZ wave frequency is over.In order to use the ultrasonic detection means, must generate as ultrasonic wave and receiving damnation.Complete the functions of the device is called the
中原工学院毕业设计(论文)译文
ultrasonic sensor, habit, ultrasonic transducer or ultrasonic probe.Ultrasonic sensors have both transmitters and receivers, but a ultrasonic sensors can also has the sending and receiving the sound waves of the dual role.Ultrasonic sensors is using the principle of piezoelectric effect and ultrasonic energy conversion, be in namely emit ultrasonic, energy conversion, launch ultrasonic, And in the stockades, received echo ultrasonic vibration into electrical signal.Ultrasonic ranging principle generally USES the time method for the crossing.First measured ultrasonic from the launch to meet obstacles returns experience of time, again multiply ultrasonic speed of get twice the distance between the sound source and obstacles.Measuring distance a variety of ways, short can use ruler, long-range laser displacement etc, are suitable for high accuracy of ultrasonic ranging in long distance measurement.Because of ultrasound in standard air of propagation speed 331.45 meters per second, by single-chip microcomputer is responsible for timing, SCM use 12.0 M crystals, so the system of measurement precision theory can achieve mm level.Because of ultrasonic directivity strong, energy consumption is slow, in a medium transmission distance, thus ultrasonic can be used for distance measurement.Using ultrasonic detection distance, the design is more convenient, computing procese also relatively simple, and the measurement precision can also meet the requirements.Ultrasonic generator can be divided into two kinds: one kind is to use electrical means producing ultrasonic, one kind is with mechanical approach to producing ultrasonic.This design belongs to nearly distance measurement, can use commonly used the piezoelectric ultrasonic transducer to achieve trigger unit.Using ultrasonic ranging work, can according to measuring launch reflection wave wave and the time interval between the measured distance, so as to achieve the effect.It mainly have three ranging methods:
(1)phase assay, phase assays high precision, but detection though limited range,(2)sound amplitude assay, acoustic amplitude assay vulnerable reflection wave influence;
(3)ferrying more time assay, crossing the time assay way of working is simple, intuitive, in hardware control and software design are very easy to implement.Its principle is: from the launch emit ultrasonic detection sensor, the gas medium spread to receive sensor of time, this time is crossing the more time.This design is the use of ultrasonic ranging the crossing the time assay.In the mobile vehicles of the application 15
中原工学院毕业设计(论文)译文
of ultrasonic sensor is the use of ultrasound in air of directional spread and solid reflective characteristics(p-wave)and by receiving their launch ultrasonic reflecting signal, according to the ultrasonic issued and echo receiving the Windows and propagation speed, calculate transmission distance, thus obtains the obstacles to vehicle distance.中原工学院毕业设计(论文)译文
2.A principle of ultrasonic distance measurement
2.1 the principle of piezoelectric ultrasonic generator
Piezoelectric ultrasonic generator is the use of piezoelectric crystal resonators to work.Ultrasonic generator, the internal structure as shown, it has two piezoelectric chip and a resonance plate.When it’s two plus pulse signal, the frequency equal to the intrinsic piezoelectric oscillation frequency chip, the chip will happen piezoelectric resonance, and promote the development of plate vibration resonance, ultrasound is generated.Conversely, if the two are not inter-electrode voltage, when the board received ultrasonic resonance, it will be for vibration suppression, then it becomes the ultrasonic receiver.The traditional way to determine the moment of the echo’s arrival is based on thresholding the received signal with a fixed reference.The threshold is chosen well above the noise level, whereas the moment of arrival of an echo is defined as the first moment the echo signal surpasses that threshold.The intensity of an echo reflecting from an object strongly depends on the object’s nature, size and distance from the sensor.Further, the time interval from the echo’s starting point to the moment when it surpasses the threshold changes with the different intensities arriving exactly at the same tome will surpass the threshold at different moments.The stronger one will surpass the threshold earlier than the weaker, so it will be considered as belonging to a nearer object.2.2 The principle of ultrasonic distance measurement Ultrasonic transmitter in a direction to launch ultrasound, in the moment to launch the beginning of time at the same time, the spread of ultrasound in the air, obstracles on his way to return immediately, the ultrasonic reflected wave wave received by the reveiver immediately stop the clock.Ultrasonic in the air as the propagation velocity of 340m/s, according to the timer records the time t, we can calculate the distance between the launch distance barrier(s), that is:s=340t/2
中原工学院毕业设计(论文)译文
3.Ultrasonic Ranging System for the Second Circuit Design
System is characterized by single-chip microcomputer to control the use of ultrasonic transmitter and ultrasonic receiver since the launch from time to time, single-chip selection of 8751,economic-to –use, and the chip has 4K of ROM, to facilitate programming.Circuit schematic diagram shown in Figure 1.Figure 1 circuit principle diagram
中原工学院毕业设计(论文)译文
3.1 40 kHz ultrasonic pulse generated with the launch
Ranging system using the ultrasonic sensor of piezoelectric sensors UCM40, its operating voltage of the pulse signal is 40kHz, which by the single-chip implementation of the following procedures to generate.Puzel:mov 14h,# 12h;ultrasonic firing continued 200ms here:cpl pl.0;output 40 kHz square wave
nop;
nop;nop;djnz 14h, here;ret Ranging in front of single-chip termination circuit P1.0 input port, single chip implementation of the above procedure, the P1.0 port in a 40kHz pulze output signal, after amplification transistor T, the drive to launch the first ultrasonic UCM40T, issued 40kHz ultrasonic pulse, and the continued launch of 200ms.Ranging the right and the left side of the circuit, respectively, then input port P1.1 and P1.2, the working principle and circuit in front of the same location.3.2 Reception and processing of ultrasonic
Used to receive the first launch of the first pair UCM40R, the ultrasonic pulse modulation signal into an alternating voltage, the op-amp amplification IC1A and after polarization IC1B to IC2.IC2 is locked loop with audio decoder chip LM567, internal voltage-controlled oscillator center frequency of f0=1/1.1R8C3, capacitor C4 determine their target bandwidth.R8-conditioning in the launch of the carrier frequency on the LM567 input signal is greater than 25Mv, the output from the high jump 8 feet into a low-level, as interrupt request signals to the single-chip processing.Ranging in front of single-chip termination circuit port INT0 interrupt the highest priority, right or left location of the output circuit with output gete IC3A access INT1 port single-chip, while single-chip P1.3 and P1.4 received input IC3A, interrupted by the process to identify the source code is as follows: receivel:
push psw
push ace
中原工学院毕业设计(论文)译文
cir ex1: related external interrupt 1
jnb p1.1, right;P1.1 pin to 0, ranging from right to interrupt service rountine circuit
jnb p1.2, left;P1.2 pin to 0, to the left ranging circuit
interrupt service routine return:SETB EX1;open external interrupt 1
pop
acc pop
psw reti right:…;right location entrance circuit interrupt service rountine
Ajmp Return left:…;left Ranging entrance circuit interrupt service rountine
Ajmp Return
3.3 The calculation of ultrasonic propagation time
When you start firing at the same time start the single-chip circuitry within the timer T0, the use of timer counting function records the time and the launch of ultrasonic reflected wave received time when you receive the ultrasonic reflected wave, the receiver circuit outputs a negative jump in the end of INT0 or INT1 interrupt request generates a signal, single-chip microcomputer in response to external interrupt request, the implementation of the external interrupt service subroutine, read the time difference, calculating the distance.Some of its source is as follows: RECEIVE0: PUSH PSW PUSH ACC CLR EX0;related external interrupt 0 MOV R7, TH0;read the time value MOV R6, TL0 CLR C MOV A, R6 SUBB A,#0BBH;calculate the tome difference MOV 31H, A;storage results MOV A, R7 SUBB A,#3CH
中原工学院毕业设计(论文)译文
MOV 30H,A SETB EX0;open external interrupt 0 POP ACC POP PAW RETI For a flat target, a distance measurement consists of two phases: a coarse measurement and, a fine measurement: Step 1: Transmission of one pulse train to produce a simple ultrasonic
Wave.Step 2: Changing the gain of both echo amplifiers according to equation,until the echo is detected.Step 3:detection of te amplitudes anf zero-crossing times of both echoes.Step 4:setting the gains of both echo amplifiers to normalize the output at, say 3 volts.Setting the period of the next pulses according to the: period of echoes.Setting the time window according to the data of step 2.Step 5:sending two pulse trains to produce an interfered wave.Testing the zero-crossing in the echo,detemine to otherwise calculate to by interpolation using the amplitudes near the trough.Derive t sub ml and t sub m2.Step6: Calculation of the distance y using equation.中原工学院毕业设计(论文)译文
4.The ultrasonic ranging system software design
Software is divided into two parts, the main program and interrupt service routine.Completion of the work of the main program is initialized, each sequence of ultrasonic transmitting and receiving control.Tnterrupt service routines from time to complete three of the rotation direction of ultrasonic launch, the main external interrupt service subroutine to resd the value of completion time, distance calculation, the results of the output and so on.中原工学院毕业设计(论文)译文
5.Conclusions
Required measuring range of 30cm~200cm objects inside the plane to do a number of measurements found that the maximum error is 0.5cm, and good reproducibility.Single-chip design can be seen on the ultrasonic ranging system has a hardware structure is simple, reliable, small features such as measurement error.Therefore, it can be used not only for mobile robot can be used in other detection systems.Thoughts: As for why the receiver do not have the transistor amplifier circuit, because the magnification well, integrated amplifier, but also with automatic gain control level, magnification to 76dB, the center frequency is 38k to 40k, is exactly resonant ultrasonic sensors frequency.中原工学院毕业设计(论文)译文
REFERENCES 1.Fox,J.D.,Khuri-Yakub, B.T.and Kino, G.S., ‖High Frequency Acoustic Wave Measurement in Air‖, in Proceedings of IEEE 1983 Ultrasonic Symposium, October 31-2 November, 1983, Atlanta, GA, pp.581-4.2.Martin Abreu,J.M.,Ceres,R.and Freire, T.,‖Ultrasonic Ranging: Envelope Analysis Gives Improved Accuracy‖, Sensor Review, Vol.12No.1,1992, pp.17-21.3.Parrilla, M., Anaya,J.J and Fritsch C.,‖Digital Signal Processing Techniques for High Accuracy Ultrasonic Range Measurement:,IEEE Transactions: Instrumentation and Measurement.Vol.40 No.4, August 1991,pp.750-63.4.Canali, C., Cicco, G.D., Mortem, B., Prudenziati, M., and Taron, A., ―A Temperature Compensated Ultrasonic Sensor Operating in Air for Distance and Proxinmity Measurement‖, IEEE Trasaction on Industry Electronics, Vol, IE-29 No.4,1982, pp.336-41.5.Martin, J.M., Ceres, R., Calderon, L and Freire, T., ‖Ultrasonic Ranging Gets Themal Correction‖, Sensor Review, Vol, 9 No.3, 1989,pp.153-5.24