超声波测距外文文献加中文翻译毕业设计

附录A 英文原文

ULTASONIC RANGING IN AIR

G. E. Rudashevski and A. A. Gorbatov

One of the most important problems in instrumentation technology is the remote,contactless measurement of distances in the order of to 10 m in a problem occurs,for instance,when measuring the relativethre edimensional position of separate machine members or structural possibilities for its solution are opened up by utilizing ultrasonic vibrations as an information physical properties of air,in which the measurements are made,permit vibrations to be employed at frequencies up to 500 kHz for distances up to 0.5 m between a member and the transducer,or up to 60 kHz when ranging on obstacles located at distances up to 10 m.

The problem of measuring distances in air is somewhat different from other problems in the a -pplication of the possibility of using acoustic ranging for this purpose has been known for a long time,and at first glance appears very simple,nevertheless at the present time there are only a small number of developments using this method that are suitable for practical main difficulty here is in providing a reliable acoustic

three-dimensional contact with the test object during severe changes in the air's characteristic.

Practically all acoustic arrangements presently known for checking distances use a method of measuring the propagation time for certain information samples from the radiator to the reflecting member and back.

The unmodulated acoustic(ultrasonic)vibrations radiated by a transducer are not in themselves a source of order to transmit some informational communication that can then be selected at the receiving end after reflection from the test member,the radiated vibrations must be this case the ultrasonic vibrations are the carrier of the information which lies in the modulation signal,.,they are the means for establishing the spatial contact between the measuring instrument and the object being measured.

This conclusion,however,does not mean that the analysis and selection of parameters for the carrier vibrations is of minor the contrary,the frequency of the carrier vibrations is linked in a very close manner with the coding method for the informational communication,with the passband of the receiving and radiating elements in the apparatus,with the spatial characteristics of the ultrasonic communication channel,and with the measuring accuracy.

Let us dwell on the questions of general importance for ultrasonic ranging in air,namely:on the choice of a carrier frequency and the amount of acoustic power received.

An analysis shows that with conical directivity diagrams for the radiator and receiver,and assuming that

the distance between radiator and receiver is substantially smaller than the distance to the obstacle,the

amount of acoustic power arriving at the receiving area Pr for the case of reflection from an ideal plane

surface located at right angles to the acoustic axis of the transducer comes to

where Prad is the amount of acoustic power radiated,B is the absorption coefficient for a plane wave in

the medium,L is the distance between the electroacoustic transducer and the test me -mber,d is the diameter

of the radiator(receiver),assuming they are equal,and c~is the angle of the directivity diagram for the

electroacoustic transducer in the radiator.

Both in Eq.(1)and below,the absorption coefficient is dependent on the amplitude and not on the

intensity as in some works[1],and therefore we think it necessary to stress this difference.

In the various problems of sound ranging on the test members of machines and structures,the

relationship between the signal attenuations due to the absorption of a planewave and due to the

geometrical properties of the sound beam are,as a rule,quite must be pointed out that the choice of the

geometrical parameters for the beam in specific practical cases is dictated by the shape of the reflecting

surface and its spatial distortion relative to some average position.

Let us consider in more detail the relationship betweenthe geometric and the power parameters of

acoustic beams for the most common cases of ranging on plane and cylindrical structural members.

It is well known that the directional characteristic W of a circular piston vibrating in an infinite baffle is a

function of the r atio of the piston's diameter to the wavelength d/λ as found from the following expression:

(2)

where Jl is a Bessel function of the first order and α is the angle between a normal to the piston and a

line projected from the center of the piston to the point of observation(radiation).

From Eq.(2)it is readily found that a t w o-t o-o n e reduction in the sensitivity of a radiator with respect

to sound pressure will occur at the angle

（3）

For angles α≤.(3)can be simplified to

（4） where c is the velocity of sound in the medimaa and f is the frequency of the radiated vibrations.

It follows from Eq.(4)that when radiating into air where c=330 m/s e c,the necessary diameter of the

radiator for a spedfied angle of the directivity diagram at the level of pressure taken with respect to the axis can befound to be fd

c 76.05.0≈

α

（5）

where disincm,f is in kHz,and α is in degrees of angle.

Curves are shown in plotted from Eq.(5)for six angles of a radiator's directivity diagram.

The directivity diagrm needed for a radiator is dictated by the maximum distance to be measured and by

the spatial disposition of the test member relative to the other structural order to avoid the incidence of

signals reflected from adjacent members onto the acoustic receiver,it is necessary to provide a small angle of

divergence for the sound beam and,as far as possible,a small-diameter two requirements are mutually

inconsistent since for a given radiation frequency a reduction of the beam's divergence angle requires an

increased radiator diameter.

In fact,the diameter of the"sonicated"spot is controlled by two variables,namely:the diameter of the

radiator and the divergence angle of the sound the general case the minimum diameter of

the"sonicated"spot Dmin on a plane surface normally disposed to the radiator's axis is given by

（6）

where L is the least distance to the test surface. The specified value of Dmin corresponds to a radiator with a diameter

（7）

As seen from Eqs.(,6)and(7),the minimum diameter of the"sonieated"spot at the maximum required

distancecannot be less than two radiator ,with shorter distances to the obstacle the size of the"sonicated"

surface is less.

Let us consider the case of sound ranging on a cylindrically shaped object of radius problem is to measure the distance from the electroacoustic transducer to the side surface of the cylinder with its

various possible displacements along the X and Y necessary angleαof the radiator's directivity diagram is

given in this case by the expression

（8） whereα is the value of the angle for th e directivity diagram,Ymax is the maximum displacement of the cylinder's center from the acoustic axis,and Lmin is the minimum distance from the center of the

electroacoustic transducer to the reflecting surface measured along the straight line connecting the center of

the m e m b e r with the center of the transducer.

It is clear that when measuring distance,the"running"time of the information signal is controlled by the

length of the path in a direction normal to the cylinder's surface,or in other words,the measure distance is

f

d α1400

≈f

cL d 5.1=f

cL

D 6min =min max

arcsin

L R y +≥α

always the shortest statement is correct for all cases of specular reflection of the vibrations from the test

simultaneous solution of Eqs.(2)and(8)when W= leads to the following expression:

(9) In the particular case where the sound ranging takes place in air having c=330 m/sec,and on the

asstunption that L min <

the fomula (10) where d is in cm and f is in kHz. Curves are shown in for determining the necessary diameter of the radiator as a function of the ratio

of the cylinder's radius to the maximum displacement from the axis for four radiation shown in this figure is

the directivity diagram angle as a function of R and Y rnax for four ratios of m i n i m u m distance to radius.

The ultrasonic absorption in air is the second factor in determining the resolution of ultrasonic ranging

devices and their range of results of physical investigations concerning the measurement of ultrasonic

vibrations air are given in[1-3].Up until now there has been no unambiguous explanation of the discrepancy

between the theoretical and expe -rimental absorption results for ultrasonic vibrations in ,for frequencies in

the order of 50 to 60 kHz at a temperature of+25o C and a relative humidity of 37%the energy absorption

coefficient for a plane wave is about m while the theoretical value is d B/ absorption coefficient B as a

function of frequency for a temperature of+25o Cand a humidity of 37%according to the data in[2]can be

described by Table 1.

The absorption coefficient depends on the relative ,for frequencies in the order of 10 to 20kHz the

highest value of the absorption coefficient occurs at 20%humidity[3],and at 40%humidity the absorption is

reduced by about two to frequencies in the order of 60 kHz the maximum absorption occurs at

humidity,dropping when it is increased to 98% or lowered to 10%by a factor of approximately four to one.

The air temperature also has an appreciable effect on the ultrasonic absorption[1].When the

temperature of the medium is increased from+10 to+30,the absorption for frequencies between 30 and 50

kHz increases by about three to one.

Taking all the factors noted above into account we arrive at the following approximate values for the

absorption coefficient:at a frequency of 60 kHz /3min =0.15 m -1 and~max=;at a frequency of 200 kHz/~min=0.6

m -1 and B max =2 m -1.

（11）

()max

min 76.0y L R d +=λmax

25fy R d ≈

The values for the minimum~min and rnaxil-num~max"transmittance"coefficients were obtained in the

a bsence of aerosols and difference is the result of the possible variations in temperature over the range

from -3 0 to+50~and in relative hmnidity over the range from 10 to 98%.The overall value of

the"transmittance"is obtained by multiplying the values of g and 0 for given values of L,f,and d.

L I T E R A T U R E C I T E D

Moscow(1957).

Moscow(1960).

附录B 中文翻译

在空气中超声测距

G. E. Rudashevski and A. A. Gorbatov

在仪器技术中远程是最重要的一个问题。在空气中，从0.2米至10米非接触式测量距离时，涉及到

了这个问题，例如，在测量时个别机件或结构单位的相对三维位置。有趣的是，是利用超声振动作为信

息运输工具，开启了解决办法的可能性.在空气这个自然道具中，进行测量的是雇用成员和传感器之间

距离0.5米的时候，允许振动频率高达500千赫，或当与障碍物之间修正距离延伸达10米时候，振动

频率高达60千赫兹。

应用超声波在空气中测量距离不同于其他的问题。虽然能否利用声波修正测距的可行性已经研究

了很长一段时间，乍一看似乎很简单，但是目前只有为数不多的新发明使用这种适合实际目的方法，主

要困难是在有严重特有变化的空气中提供一个可靠试验对象去接触三维声波。

几乎所有的目前已知用来校验距离使用的，都是为了某些来自用来反射成员和后面的散热器信息样

本，测量传播时间解决声音的办法。

该未解调的声（超声）振动由传感器辐射的，本身并不是一个信息来源. 在接收端，来自测试会员反射

后，为了传递一些情报信息，因而被选定后，辐射振动一定会被调制。在这种情况下，超声波振动是在

于调制信号的信息的承运人，即他们就是在测量仪器和测量稳定的对象之间建立了空间三维接触的手

段。

这一结论，但是，并不意味着分析和选择的参数承运人振动重要性小.正相反，承运人振动频率与

信息沟通编码方法，与接收通频带和仪器中的辐射元素，与超声波空间特有的沟通渠道，以及测量精度

是具有非常密切的联系方式。

让我们谈具有普遍意义的空气中超声波测距问题，即：载波频率和的被普遍认为标准的声音数额的选择。

（1）

在P rad 辐射声功率， B 是平面波在介质中吸收系数为， L 是声电传感器和测试箱之间的距离， D 是散热器（接收）的直径， C 是的电声换能器的散热器方向性图的角度。 24411?????? ??+=-d Ltg e P P L rad r αβ

αλπ

αλπsin sin 21

d d J W ??? ??=在均衡器 （ 1 ）及以下，和作品[ 1 ]一样，吸收系数依赖于振幅和而不是强度，因此，我们认为

有必要强调这种差异。

图1

图2

图3

在声音的各种问题上，包括成员测试设备和结构的关系，由于信号衰减吸收的平面和适当的几何性

质的声束是，作为一项规则，一定是相差甚远的.需要指出的是，选择的实际情况中光束具体的几何参

数，是基于形状的反射面和空间的一些失真相对平均排布。

让我们考虑一下更详细的几何关系和声束的动力参数这个最常见包括平面和圆柱结构的成员情况。

众所周知，定向特性瓦的一个圆形活塞振动无限挡板是一个活塞比例函数,d/ λ为下列表达式基础：

（2）

从均衡器（ 2 ）中很容易发现，在减少两到一个敏感性散热器方面,声压级角度将会引起注意。 （3） 表1 f0kHz 10 20 30 40 50 60 80 100 150 200 300 500

β0dB/m

2 4 6 9 16 40 对角可以简化为 α ≤ . （

3 ）

（4） 其中c 是中期声速 ,F 是辐射震动的频率 λα76.0arcsin 5.0=fd

c 76.05.0≈

α

它遵循均衡器（ 4 ） ，当辐射到空中，其中c = 300米/秒，在级的压力面，散热器为采取的轴的直径用于指定角度的方向性图上是必要的

（5） 其中d 是厘米，khz 是千赫， α是度角。

在图1中显示的曲线图是均衡器 （ 5 ）中 6个角度散热器的方向性图。

事实上，直径的“超声波降解标本”现场控制的两个变量，即：直径的散热器和发散角的声音束.一般情况下，最小直径的“超声波降解标本”在现场飞机表面处理，通常倾向于散热器的轴心 。 （6） L 是测试表面最小的距离。

对应的散热器直径 （7） （7）作为从均衡器（ 6 ）及（ 7 ） ，“声振”现场最小直径，最高要求散热器直径距离不得少于2.自然的，以短距离的障碍的大小， “声振“表面的更少。

其中d 是厘米，khz 的在千赫， α是度角 让我们考虑在半径为R 的中声波测距的情况。

问题是在X 和Y 中坐标轴上衡量从声电传感器的到圆柱形物体侧表面的距离 缸其各种可能的位移沿X 和Y 轴，散热器的方向性图角度α的必要性在这种情况下被用词组的形式表示出来。

（8） 在这里是α的价值角度的方向性图，y max 是声学轴中心最大位移气瓶，Lmin 是从中央电传感器的反射面测量沿直线连接的中心与中心会员的传感器之间最短距离

很显然，当测量距离，在信息信号“运行”时，对于在圆柱体表面来说在一个标准方向上 ， 轨迹的长度是受控制的。

或者换句话说，始终衡量距离是最短的一个。对于所有来自测试表面一次性往复震动镜面反射情况这个声明都是正确的。当W = 时决均衡器（ 2 ）及（ 8 ）的连立解有下面的表达式： （9）

在特定情况下发生的各种声音在空气中传播有速度是? = 300米/秒，并假定Lmin<

f

d α1400≈

f cL D 6min

=f cL

d 5.1=

min

max arcsin

L R y +≥α()max

min 76.0y L R d +=λmax

25fy R d ≈

在空气中超声的吸收是在决心解决超声波测距装置及其一系列功能的第二个因素. 在[ 1-3 ]中给出了空气中关于测量超声波振动物理调查结果。到目前为止，在空气中吸收超声波振动结果实验在理论解释和实验之间 已有没有明确的的差异，因此 ，对于频率为50至60千赫，在温度的25℃和相对湿度37 ％时，平面波能量吸收系数为m ，与此同时理论值为 d B/m 。吸收系数B ，温度25 ℃，湿度为37 ％时的数据显示在[ 2 ]表1中

吸收系数取决于相对湿度.因此 ，为了得到吸收系数最高价值为10到20kHz ，发生在湿度[ 3 ]时为20 ％，并在吸收湿度减少约二分之一时为40 ％。对于最大吸收频率为60千赫的情况， 在30℃时湿度下降，结果会提高到98 ％或下降到10 ％，其系数约为四比一。

空气温度超声吸收也有明显的影响 [ 1 ] 。当温度从+10℃升至中期+30℃，吸收的频率在30至50千赫期间增加了约三分之一 。

所有因素考虑进来我们获得了如下近似值：吸声系数：在频率为60khz 时 βmin= 0.15 m -1,βmax= 0.5 m -1 ;在频率为200khz 时βmin= 0.6 m -1,βmax = 2 m -1。

正在审议的关系，生动地显示在图3中。 在上部曲线图的G = F （L ）中将散热器的方向性总角度的价值分为五个，在那里

(11) 参考文献

Moscow(1957). Moscow(1960). 2

2311?????? ??+=fd Lc ξ

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关于力的外文文献翻译、中英文翻译、外文翻译

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平面设计中英文对照外文翻译文献

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设计，“其实质是使以信息，形成以思想，言论和感觉的经验”。 在唐朝（ 618-906 ）之间的第4和第7世纪的木块被切断打印纺织品和后重现佛典。阿藏印在868是已知最早的印刷书籍。 在19世纪后期欧洲，尤其是在英国，平面设计开始以独立的运动从美术中分离出来。蒙德里安称为父亲的图形设计。他是一个很好的艺术家，但是他在现代广告中利用现代电网系统在广告、印刷和网络布局网格。 于1849年，在大不列颠亨利科尔成为的主要力量之一在设计教育界，该国政府通告设计在杂志设计和制造的重要性。他组织了大型的展览作为庆祝现代工业技术和维多利亚式的设计。 从1892年至1896年威廉?莫里斯凯尔姆斯科特出版社出版的书籍的一些最重要的平面设计产品和工艺美术运动，并提出了一个非常赚钱的商机就是出版伟大文本论的图书并以高价出售给富人。莫里斯证明了市场的存在使平面设计在他们自己拥有的权利，并帮助开拓者从生产和美术分离设计。这历史相对论是，然而，重要的，因为它为第一次重大的反应对于十九世纪的陈旧的平面设计。莫里斯的工作，以及与其他私营新闻运动，直接影响新艺术风格和间接负责20世纪初非专业性平面设计的事态发展。 谁创造了最初的“平面设计”似乎存在争议。这被归因于英国的设计师和大学教授Richard Guyatt，但另一消息来源于20世纪初美国图书设计师William Addison Dwiggins。 伦敦地铁的标志设计是爱德华约翰斯顿于1916年设计的一个经典的现代而且使用了系统字体设计。 在20世纪20年代，苏联的建构主义应用于“智能生产”在不同领域的生产。个性化的运动艺术在俄罗斯大革命是没有价值的，从而走向以创造物体的功利为目的。他们设计的建筑、剧院集、海报、面料、服装、家具、徽标、菜单等。 Jan Tschichold 在他的1928年书中编纂了新的现代印刷原则，他后来否认他在这本书的法西斯主义哲学主张，但它仍然是非常有影响力。 Tschichold ，包豪斯印刷专家如赫伯特拜耳和拉斯洛莫霍伊一纳吉，和El Lissitzky 是平面设计之父都被我们今天所知。 他们首创的生产技术和文体设备，主要用于整个二十世纪。随后的几年看到平面设计在现代风格获得广泛的接受和应用。第二次世界大战结束后，美国经济的建立更需要平面设计，主要是广告和包装等。移居国外的德国包豪斯设计学院于1937年到芝加哥带来了“大规模生产”极简到美国;引发野火的“现代”建筑和设计。值得注意的名称世纪中叶现代设计包括阿德里安Frutiger ，设计师和Frutiger字体大学;保兰德，从20世纪30年代后期，直到他去世于1996年，采取的原则和适用包豪斯他们受欢迎的广告和标志设计，帮助创造一个独特的办法，美国的欧洲简约而成为一个主要的先驱。平面设计称为企业形象;约瑟夫米勒，罗克曼，设计的海报严重尚未获取1950年代和1960年代时代典型。 从道路标志到技术图表，从备忘录到参考手册，增强了平面设计的知识转让。可读性增强了文字的视觉效果。 设计还可以通过理念或有效的视觉传播帮助销售产品。将它应用到产品和公司识别系统的要素像标志、颜色和文字。连同这些被定义为品牌。品牌已日益成为重要的提供的服务范围，许多平面设计师，企业形象和条件往往是同时交替使用。

超声波测距仪外文资料翻译

Ultrasonic distance meter Document Type and Number:United States Patent 5442592 Abstract:An ultrasonic distance meter cancels out the effects of temperature and humidity variations by including a measuring unit and a reference unit. In each of the units, a repetitive series of pulses is generated, each having a repetition rate directly related to the respective distance between an electroacoustic transmitter and an electroacoustic receiver. The pulse trains are provided to respective counters, and the ratio of the counter outputs is utilized to determine the distance being measured. A.BACKGROUND OF THE INVENTION This invention relates to apparatus for the measurement of distance and, more particularly, to such apparatus which transmits ultrasonic waves between two points. Precision machine tools must be calibrated. In the past, this has been accomplished utilizing mechanical devices such as calipers, micrometers, and the like. However, the use of such devices does not readily lend itself to automation techniques. It is known that the distance between two points can be determined by measuring the propagation time of a wave travelling between those two points. One such type of wave is an ultrasonic, or acoustic, wave. When an ultrasonic wave travels between two points, the distance between the two points can be measured by multiplying the transit time of the wave by the wave velocity in the medium separating the two

10kV小区供配电英文文献及中文翻译

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英文文献及中文翻译

毕业设计说明书 英文文献及中文翻译 学院：专 2011年6月 电子与计算机科学技术软件工程

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基于51单片机的超声波测距仪之倒车雷达作品设计毕业论文

基于51单片机的超声波测距仪之倒车雷达作品设计毕业论文

毕业设计（论文）原创性声明和使用授权说明 原创性声明 本人郑重承诺：所呈交的毕业设计（论文），是我个人在指导教师的指导下进行的研究工作及取得的成果。尽我所知，除文中特别加以标注和致谢的地方外，不包含其他人或组织已经发表或公布过的研究成果，也不包含我为获得及其它教育机构的学位或学历而使用过的材料。对本研究提供过帮助和做出过贡献的个人或集体，均已在文中作了明确的说明并表示了谢意。 作者签名：日期： 指导教师签名：日期： 使用授权说明 本人完全了解大学关于收集、保存、使用毕业设计（论文）的规定，即：按照学校要求提交毕业设计（论文）的印刷本和电子版本；学校有权保存毕业设计（论文）的印刷本和电子版，并提供目录检索与阅览服务；学校可以采用影印、缩印、数字化或其它复制手段保存论文；在不以赢利为目的前提下，学校可以公布论文的部分或全部内容。 作者签名：日期：

学位论文原创性声明 本人郑重声明：所呈交的论文是本人在导师的指导下独立进行研究所取得的研究成果。除了文中特别加以标注引用的内容外，本论文不包含任何其他个人或集体已经发表或撰写的成果作品。对本文的研究做出重要贡献的个人和集体，均已在文中以明确方式标明。本人完全意识到本声明的法律后果由本人承担。 作者签名：日期：年月日 学位论文版权使用授权书 本学位论文作者完全了解学校有关保留、使用学位论文的规定，同意学校保留并向国家有关部门或机构送交论文的复印件和电子版，允许论文被查阅和借阅。本人授权大学可以将本学位论文的全部或部分内容编入有关数据库进行检索，可以采用影印、缩印或扫描等复制手段保存和汇编本学位论文。 涉密论文按学校规定处理。 作者签名：日期：年月日 导师签名：日期：年月日

英文论文及中文翻译

International Journal of Minerals, Metallurgy and Materials Volume 17, Number 4, August 2010, Page 500 DOI: 10.1007/s12613-010-0348-y Corresponding author: Zhuan Li E-mail: li_zhuan@https://www.wendangku.net/doc/8a430720.html, ? University of Science and Technology Beijing and Springer-Verlag Berlin Heidelberg 2010 Preparation and properties of C/C-SiC brake composites fabricated by warm compacted-in situ reaction Zhuan Li, Peng Xiao, and Xiang Xiong State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China (Received: 12 August 2009; revised: 28 August 2009; accepted: 2 September 2009) Abstract: Carbon fibre reinforced carbon and silicon carbide dual matrix composites (C/C-SiC) were fabricated by the warm compacted-in situ reaction. The microstructure, mechanical properties, tribological properties, and wear mechanism of C/C-SiC composites at different brake speeds were investigated. The results indicate that the composites are composed of 58wt% C, 37wt% SiC, and 5wt% Si. The density and open porosity are 2.0 g·cm–3 and 10%, respectively. The C/C-SiC brake composites exhibit good mechanical properties. The flexural strength can reach up to 160 MPa, and the impact strength can reach 2.5 kJ·m–2. The C/C-SiC brake composites show excellent tribological performances. The friction coefficient is between 0.57 and 0.67 at the brake speeds from 8 to 24 m·s?1. The brake is stable, and the wear rate is less than 2.02×10?6 cm3·J?1. These results show that the C/C-SiC brake composites are the promising candidates for advanced brake and clutch systems. Keywords: C/C-SiC; ceramic matrix composites; tribological properties; microstructure [This work was financially supported by the National High-Tech Research and Development Program of China (No.2006AA03Z560) and the Graduate Degree Thesis Innovation Foundation of Central South University (No.2008yb019).] 温压-原位反应法制备C / C-SiC刹车复合材料的工艺和性能 李专，肖鹏，熊翔 粉末冶金国家重点实验室，中南大学，湖南长沙410083，中国（收稿日期：2009年8月12日修订：2009年8月28日;接受日期：2009年9月2日） 摘要：采用温压?原位反应法制备炭纤维增强炭和碳化硅双基体(C/C-SiC)复合材

英文文献及中文翻译撰写格式

关于毕业设计说明书（论文）英文文献及中文翻译撰写格式 为提高我校毕业生毕业设计说明书（毕业论文）的撰写质量，做到毕业设计说明书（毕业论文）在内容和格式上的统一和规范，特规定如下: 一、装订顺序 论文（设计说明书）英文文献及中文翻译内容一般应由3个部分组成，严格按以下顺序装订。 1、封面 2、中文翻译 3、英文文献（原文） 二、书写格式要求 1、毕业设计（论文）英文文献及中文翻译分毕业设计说明书英文文献及中文翻译和毕业论文英文文献及中文翻译两种，所有出现相关字样之处请根据具体情况选择“毕业设计说明书” 或“毕业论文”字样。 2、毕业设计说明书（毕业论文）英文文献及中文翻译中的中文翻译用Word 软件编辑，英文文献用原文，一律打印在A4幅面白纸上，单面打印。 3、毕业设计说明书（毕业论文）英文文献及中文翻译的上边距:30mm；下边距:25mm；左边距:3Omm；右边距:2Omm；行间距1.5倍行距。 4、中文翻译页眉的文字为“中北大学2019届毕业设计说明书” 或“中北大学××××届毕业论文”，用小四号黑体字，页眉线的上边距为25mm；页脚的下边距为18mm。 5、中文翻译正文用小四号宋体，每章的大标题用小三号黑体，加粗，留出上下间距为：段前0.5行，段后0.5行；二级标题用小四号黑体，加粗；其余小标题用小四号黑体，不加粗。 6、文中的图、表、附注、公式一律采用阿拉伯数字分章编号。如图1.2，表2.3，附注3.2或式4.3。 7、图表应认真设计和绘制,不得徒手勾画。表格与插图中的文字一律用5号宋体。

每一插图和表格应有明确简短的图表名，图名置于图之下，表名置于表之上，图表号与图表名之间空一格。插图和表格应安排在正文中第一次提及该图表的文字的下方。当插图或表格不能安排在该页时，应安排在该页的下一页。 图表居中放置，表尽量采用三线表。每个表应尽量放在一页内，如有困难，要加“续表X.X”字样，并有标题栏。 图、表中若有附注时，附注各项的序号一律用阿拉伯数字加圆括号顺序排，如:注①。附注写在图、表的下方。 文中公式的编号用圆括号括起写在右边行末顶格，其间不加虚线。 8、文中所用的物理量和单位及符号一律采用国家标准，可参见国家标准《量和单位》(GB3100~3102-93)。 9、文中章节编号可参照《中华人民共和国国家标准文献著录总则》。

激光测距仪外文翻译

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