浙江师范大学本科毕业设计(论文)外文翻译
译文：
仿真软件开发低大型复杂腔基于UG的二次开发
李建周江应富徐家栋
西北工业大学电子与信息学院
西安710129年山西,中国
ljz@https://www.doczj.com/doc/4017668529.html,电邮
摘要---射击和弹跳射线(SBR)二次开发的基础软件是由国标库(UG)。射线跟踪的核心算法是基于优化的非均匀有理b样(NURBS)曲线表面相交算法建立在UG,导致非常高的射线路径跟踪的准确性没有啮合从而保持原有的空腔模型的准确性。它也是有效的避免同任何复杂的蛀牙,因为即使工作屏蔽的过程。两腔的几何建模及其散射模拟成一个统一的平台,形成一个易用的综合和环球环境电磁建模复杂的蛀牙。在本文开发的软件对复杂腔散射建模引入了一些数值结果显示的准确性和效率
关键词--电大型复杂cavit; 雷达截面; UG的二次开发; 射击和弹跳射线(SBR); 射线跟踪
I.介绍
雷达截面(RCS)的分析电等大型复杂洞进口或出口,双面或三面角反射器等,是计算电磁学中最重要的主题之一。低大型复杂的空腔结构,只有基于高频方法如射击和弹跳射线(SBR)[1][2][3]是合适的。传统上,为三步骤采用SBR首先,模型腔的CAD软件和网格表面的内墙,然后出口信息网格的结果;其次发现表面上的光线的反射点ray-surface十字路口和屏蔽计算;最后计算RCS即将离任的射线从腔。虽然这些网基于射线跟踪可用于任意形状的蛀牙从理论上讲,它有不准确的缺点路径建立在复杂的蛀牙导致贫穷的RCS计算精度。电大型复杂的蛀牙,射线跟踪的效率很低,由于分离腔建模与RCS计算复杂的仿真过程。为了解决这些问题, 一个强大的CAD软件,模拟电大型复杂腔并计算其RCS在同一平台。开发的软件具有以下优势: 1)腔建模和RCS计算在UG集成,因此仿真过程大大简化。2)表面啮合没有必要而射线可以追踪精度高和效率在任何任意形状的空腔。3)开发的软件是通用的电磁散射的凹面反射镜结构,如蛀牙和角落。小说射线追踪方法的新的先进的软件是基于UG的二次开发将讨论下一步,和RCS仿真结果。
II.提出的方法
射击和弹跳射线(SBR
SBR的基本概念是一个平面波由足够大量的平行光管(这里使用三角射线管)事件上的孔腔开放,每个射线管的能量集中在中线反映空腔墙基于几何光学定律和最终的开孔和树叶射线管足迹在中央的场振幅计算射线通过考虑几何差异因素,极化和材料加载腔壁。的总散射提起腔由总结发现散射场计算每个管的基尔霍夫近似衍射场的足迹在这里rim是可以忽略的比较从腔背散射的主导部分。SBR的详细理论可以在[1]和[2]。b射线追踪方法基于UG的二次开发UG是先进的CAD / CAM / CAE软件,采用非均匀有理b样(NURBS)作为其主要的建模工具。它提供了强大的建模能力和任意复杂腔建模精度高
UG的二次开发工具UG /开放的API UG和外来的程序之间的交互。UG / Open API包含大约2000个函数可以直接调用c++环境中有两种不同的模式对UG /开放项目:内部模式和外部
模式。通过构建一个动态链接库允许访问几何模型及其相对日期在国标库会话直接使用UG /开放的API函数。内部模式是使用DLL链接,在连接速度快的优势,因此,本文选择了使用UG /开放api,可以建立一种有效的射线追踪方法和高精度优化基于NURBS曲线表面相交的算法。没有复杂的啮合和屏蔽程序,新的射线跟踪方法更容易比传统项目。图1显示了发现每个光线的反射点在腔室内的墙上发达的射线追踪方法。如果利用三角射线管,四个射线包括三条边和一个中央线管,需要追踪如上所述。请全部实现的蛀牙与平台结构通过跟踪只有中央射线正如上面所讨论的。后找到一个反射点内墙,飞机的数学表达式可以使用点的坐标和单位法向量,然后反射光线的三条边射线管根据解析后的飞机可以找到。这进一步进步会带来一个巨大的减少射线追踪的时间。
图1所示。射线路径发现的射线追踪方法基于UG的二次开发。这个图显示三个入射光线入射方向发射的,和路径从参考点的s形腔,然后反映在内墙,最后到达开孔。
事实上,这部小说SBR上面讨论不仅可以应用在蛀牙,但也提供了一种新方法的电大尺寸目标的散射计算考虑多个现场互动,和过程将大大简化由于避免啮合和屏蔽需要在传统的物理光学(PO)。该方法的过程
仿真过程的方法是:1)模型或在UG中导入一个腔会话。2)自动识别腔开放光圈。3)代表了入射波与数量足够大的平行光管开孔腔和发射射线追踪。4)计算每个即将离任的背散射场在开孔管足迹。5)总结的背散射场管足迹和计算RCS的腔。
软件是通用的相对任意蛀牙和凹结构由于小说射线追踪方法建立与UG /开放API函数和一个统一的平台整合腔在UG建模和RCS计算。RAM涂层蛀牙也可以轻松地在这个软件。一个用户友好的界面与UG / Open UIStyler发达,在UG提供的GUI工具
III.数值结果
本文模拟了使用矩形腔,一个三角形的三面角反射器和一个矩形入口压电陶瓷墙来演示开发的软件。计算环境是奔腾4 - 2.8 ghz处理器,1 gb内存和Windows XP操作系统。入射波频率10 GHz,一步是程度1°模拟,俯仰角度θ从+ z方向和方位角度φ从+ x方向的模型。A. RCS的矩形腔和效率分析
图2显示了RCS的矩形腔的比较10 _,_方形截面,30 _长度[7]和模拟结果与开发的软件在不同的N(N是每个波长的节点数量,有四个光管穿过每个网格开放,所以光管的数量N×N×4平方波长)。这个数字表明快速收敛的开发了SBR的基础上提出新的射线追踪与平台腔结构。结果得到收敛当N达到4,线管的数量是64平方波长在这种情况下,N是以下模拟设置为4。模拟结果与[7]中的结果吻合较好。
θ度数
图形2. RCS的矩形腔与不同的N,平行极化
表1显示了CPU时间不同N在上面模拟,演示了该方法的效率高。
表一、CPU时间不同的N
N 2 3 4 5
CPU时间(分钟) 1.70 4.01 8.37 17.49
B.三角形的三面角反射器的RCS
RCS计算的三角形三面角反射器5 _边长度是如图3所示.我们的结果再次同意与MLFMM FEKO的结果很好。微小的区别来自于衍射场不覆盖目前在我们的结果。. 需要1.67分钟和45分钟为我们的软件和FEKO分别模拟结果。如此高的效率使它适合计算电磁散射从电大型复杂腔没有要求额外的计算机内存。
C.矩形进气道的RCS
散射模拟飞机的入口,典型的电大型复杂腔,在计算电——磁学仍然是一个挑战性的任务。图4是一个矩形入口的模型[7]和其RCS模拟软件。需要16.58分钟,25.15分钟得到的结果装具(b)和(c)。找到优秀的协议与参考文献[7]中的结果。所有这些结果验证新的射线追踪方法的准确性对于复杂的蛀牙在我们开发的软件。
(a)个矩形入口的模型
图4.矩形进气道的RCS,平行极化
IV.结论
一个新颖的射线追踪方法和相应的SBR相对任意腔散射模拟软件开发基于UG的二次开发。软件的仿真程序进行了探讨。一些结果,显示良好的准确性和效率高的散射建模电大型复杂的蛀牙。
参考文献
[1]郝凌、周Ri-cheeShung-wu李。射击和弹跳射线:RCS的计算任意形状的空腔。IEEE反式天线progat,1989年,37(2):194 – 205
[2]角色h·帕沙克,罗伯特·j·霍尔德。模态、射线和梁的技术分析开放式波导腔的电磁散射。IEEE反式天线progat,1989年,37(5):635 - 647
[3]嬴政阮。电磁辐射的基本理论。成都电讯工程学院出版社,1984年
[4]傅雅宁。计算机图形学。国防工业出版社,2005
[5]李建州,徐家栋,等。基于国标库的设计评估软件。中国无线电科学学报,2005,20(2):222 - 225
[6]李建周,徐家栋等.综合RCS(雷达截面)计算一个更有效的RCS计算方法。西北工业大学学报,2003,21(4):449 - 452
[7]郝凌,Shung-wu李Ri-chee周。高高频RCS开放腔的矩形和圆形的横截面。IEEE反式天线progat,1989年,37(5):648 – 654
原文：
Development of RCS simulation software forelectrically large complex cavitiesbased on thesecondary development of UG
LI Jianzhou JIANG Yingfu XU Jiadong School of Electronics and Information, Northwestern
Polytechnical University,Xi’an Shanxi 710129, China
E-mail : ljz@https://www.doczj.com/doc/4017668529.html,
Abstrac ---t-A shooting and bouncing ray (SBR) basedsoftware is developed by the secondary development ofUnigraphics (UG).The core algorithm of ray tracing isbased on the optimized
Non-uniform Rational B-splines(NURBS) curve-surface intersection algorithm built inUG,which results in very high accuracy of ray pathtracing without meshing thus keeping the accuracy of theoriginal cavity model.It is also efficient even if work witha complex cavities because of avoiding of shielding
process.Both geometry modeling of cavity and itsscattering simulation are into a uniformplatform,which forms an easy-using integrative anduniversal environment for electromagnetic modeling ofcomplex cavities.。In this paper, the developed software forcomplex cavity scattering modeling has been introducedwith some numerical results todemonstrate the accuracyand efficiency
Key words-electrically large complex cavit; Radar CrossSection; secondary development of UG; shooting and
bouncing rays (SBR); ray-tracing
I. INTRODUCTION
Radar cross section (RCS) analysis ofelectricallylarge complex cavities such as inlet or outlet, dihedralor trihedral corner reflector etc.,。is one of the mostimportant topics in computational electromagnetics. Forelectrically large complex cavity structures, only highfrequency based method such as shooting and bouncingray (SBR)[1][2][3] is suitable. Traditionally, there arethree steps to employ SBR Firstly, to model the cavityin CAD software and mesh surfaces of its interior walls,then exports information of the mesh results; secondlyfinding the reflection points of the rays on the surfacesby ray-surface intersection and shielding calculation;finally calculates RCS from the outgoing rays from thecavity.Although such mesh based ray tracing can beused in arbitrarily shaped cavitiestheoretically,ithasthedisadvantage of inaccurate paths founding incomplex cavities which lead to a poor RCS calculationaccuracy。. For electrically large complex cavities, the
efficiency of ray tracing is very low due to the
separation of cavity modeling and RCScalculation witha complicated simulation procedure. To address theseproblems, an integrated simulation software isdeveloped based on secondary development ofUnigraphics (UG), , a powerful CAD software, to modelelectrically large complex cavity and calculate its RCSas well in the same platform. The developed softwarehas the
following advantages: 1) Cavity modeling and RCS calculation are integrated in UG, therefore thesimulation procedure is greatly simplified.2) Surfacemeshing is not necessary whereas rays can be tracedwith high accuracy and efficiency inside anyarbitrarilyshaped cavity.3) The developed software is universalfor electromagnetic scattering from any kind of concavestructures such as cavities and corner reflectors. A novel
ray tracing method of this newadvancedsoftwarewhich is based on the secondary development of UGwill be discussed next, andtheRCSsimulation resultsare followed.II. PROPOSED METHOD A. Shooting and bouncing rays (SBR)
The basic concept of SBR is that a plane waverepresented by a sufficiently large number of parallelray tubes (triangular ray tube is used here) incident ontothe aperture at the cavity open end, each ray tube withenergy concentrated on the centre line reflects from thecavity walls based on the law of geometrical optics andeventually comes to the opening aperture and leaves a ray-tube footprint on it The field amplitude of thecentral ray is calculatedbytakingconsideration ofgeometrical divergence factor, polarization and materialloading of the cavity walls. The total scattering filed ofthe cavity is found by summing up the scattering fieldcalculated by Kirchhoff’s approximation from eachindividual tubefootprint In here the diffracting field ofthe rim isnegligible comparingtothedominateportionofbackscattering from the cavity. The detail theory ofSBR can be found in [1] and [2]. B. Ray tracing method based on secondary
development of UG
UG is advanced CAD/CAM/CAE software whichuses Non-uniform Rational B-splines (NURBS) as itsmain modeling tool. It provides powerful modelingability and high accuracy for arbitrarily complex cavitymodeling. The secondary development tools UG/Open API ofUG interact between UG and extern program. UG/OpenAPI contains approximately 2000 functions whichcanbe called directly in C++ environment There are twodifferent modes for UG/Open programs: InternalModeand External Mode. By building adynamic-link libraryallows to access thegeometry model and its relativedate within a Unigraphics session using UG/Open APIfunctions directly. Internal Mode is using DLL linkwhich has the advantage of fastin speed linking,therefore it has been chosen in this paper By usingUG/Open APIs, an efficient ray tracing method can bebuilt with high accuracy based on optimized NURBScurve-surface intersection algorithm. Withoutcomplicated meshing and shielding procedures, thenovel ray tracing method is much easier to programthan the traditional one. Figure 1 shows finding thereflection points of each ray on cavity interior wallswith developed ray tracing method.
The procedure of ray tracing is based on the
secondary development of UG: 1) Get the identifier ofthe simulated cavity. Each item modeled in UG has itsown identifier (tag) from which all the geometryinformation can be identified
ray-surface intersectionfunctions in UG/Open API. The interested parametersincluding the coordinates of the intersection points onthe cavity walls, the unit normal vectors and the radiusof principal curvature can be extracted with a fewinputting information, such as cavity identifier, thecoordinates of the starting point and the incident
direction of the ray. 3) Use Snell’s law to find thereflection ray a t the interior intersection point, andrepeating the procedures above to find the next interiorintersection point till the ray shoot out the cavity fromthe opening aperture. Also the effect of RAM coatingcan be easily added to the developed SBR procedure. Ingeneral, if triangular ray tube is utilized, four rays
including three edges and one central ray of the tube,are needed to be traced as described above.。
be achieved
for the cavities with plat structures by tracing only thecentral ray as discussed above. After finding a reflectionpoint on the interior walls, themathematical expressionof the plane can be obtained using the coordinates andunit normal vector of that point and then the reflectionrays of the three edges of the ray tube can be found
according to the resolved plane. This further
improvement leads to a huge reduction of ray tracingtime.
Figure 1. The ray paths found by the ray tracing method based on
the secondary development of UG. This figure displays three incident
rays launched from the incident direction, and the paths start from the
reference points out of the S-shaped cavity, then reflect at the interior
walls, and finally arrive at the opening aperture.
In fact, the novel SBR discussed above not only canbe applied on cavities, but also provides a new way ofscattering calculation of electrically large targets withconsidering multiple field interaction, and the procedure
will be greatly simplified thanks to avoiding meshingand shielding needed in traditional physical optics (PO). C. Process of the Proposed Method
The simulation procedure of proposed method is: 1)Model or import a cavity in UG session.
2) Identify thecavity and opening aperture automatically. 3) Representthe incident wave with a sufficiently large number ofparallel ray tubes on the opening aperture and launchray tracing in the cavity. 4)Calculate the back scatteringfield of each outgoing tube footprint on the opening aperture. 5) Sum up the back scattering field of all thetube footprints and calculate RCS of the cavity.
The software is universal for relatively arbitrarycavities and concave structures due to the novel raytracing method built with UG/Open API functions and auniform platform integrating cavity modeling and RCS
computing in UG. RAM coated cavities can also beeasily performed in this software. A user friendlyinterface is developed with UG/Open UIStyler, the GUItool provided in UG.
III. NUMERICAL RESULTS
In this paper, the simulations have been done usinga rectangular cavity, a triangular trihedral cornerreflector and a rectangular inlet with PEC walls todemonstrate the developed software. The computation
environment is Pentium 4 - 2.8GHz processor, 1GBmemory with Windows XP operating system. Incidentwave frequency is 10 GHz, and the degree step is 1° forall the simulations, the pitching
angle θ starts from +zdirection and the azimuth angle φ starts from +xdirection in the models. A. RCS of rectangular cavity and theefficiencyanalysis
Figure 2 shows the comparison of RCS of a
rectangular cavity with 10_ by 10_ square cross section,30_ length in [7] and simulated results with developedsoftware in different N (N is the number of nodes perwavelength, there are four ray tubes going through eachgrid on the opening, so the number of ray tubes isN×N×4 in a square wavelength). This figure indicatesfastconvergence of the developed SBR based on the proposed novel ray tracing for a cavity with plat
structures. The results get convergent when N reaches 4,and the number of ray tubes is 64 in a squarewavelength in this case, so N is set to 4 for thefollowing simulations. The simulated results agree wellwith the results in [7].
θ（DEGREES)
Figure 2. RCS of rectangular cavity with different N, parallelpolarization
Table 1 shows CPU time for different N in abovesimulation, which demonstrates high efficiency of theproposed method. TABLE I. CPU TIME FOR DIFFERENT N
N 2 3 4 5
CPU time (min) 1.70 4.01 8.37 17.49
B. RCS of a triangular trihedral corner reflector
Calculated RCS of a triangular trihedral cornerreflector with 5_ edge length is shown in Figure 3. Ourresult again agrees very well with the MLFMM result of
FEKO. The slight difference comes from the diffraction
field which is not covered at the moment in our result. Ittakes 1.67min and 45min for our software and FEKOrespectively, to simulate the results. Such highefficiency makes it suitable for calculatingelectromagnetic scattering from electrically largecomplex cavities without requirement of additionalcomputer memory.
Figure 3. RCS of a triangular trihedral corner reflector,?= 45°,parallel polarization
C. RCS of a rectangular inlet
Scattering simulation of inlet of aircraft, typicalelectrically large complex cavity, remains a challengingtask in computational electro- magnetics. Figure 4 is themodel of a rectangular inlet[7] and its RCS simulatedby our software. It takes 16.58min and 25.15min to getthe result of Figure4 (b) and (c) respectively. Excellentagreement is found with the result in reference [7]. Allthese results validate the accuracy of the novel raytracing method for complex cavities within
ourdeveloped software.
(a) The model of a rectangular inlet
Figure 4. RCS of a rectangular inlet, parallel polarization
IV. CONCLUSION结论
A novel ray tracing method is presented and thecorresponding SBR software is developed for relativelyarbitrary cavity scattering simulation based onsecondary development of UG. The simulationprocedure of the software is discussed. Some results aregiven which show excellent accuracy and highefficiency in scattering modeling of electrically largecomplex cavities. REFERENCES
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of open cavities with rectangular and circular cross sections.
IEEE Trans, on Antennas progat, 1989, 37(5): 648-654
工业设计原著选读 优秀的产品设计 第一个拨号电话1897年由卡罗耳Gantz 第一个拨号电话在1897年被自动电器公司引入，成立于1891年布朗强，一名勘萨斯州承担者。在1889年，相信铃声“中央交换”将转移来电给竞争对手，强发明了被拨号系统控制的自动交换机系统。这个系统在1892年第一次在拉波特完成史端乔系统中被安装。1897年，强的模型电话，然而模型扶轮拨条的位置没有类似于轮齿约170度,以及边缘拨阀瓣。电话，当然是被亚历山大格雷厄姆贝尔（1847—1922）在1876年发明的。第一个商业交换始建于1878（12个使用者），在1879年，多交换机系统由工程师勒罗伊B 菲尔曼发明,使电话取得商业成功,用户在1890年达到250000。 直到1894年，贝尔原批专利过期，贝尔电话公司在市场上有一个虚拟的垄断。他们已经成功侵权投诉反对至少600竞争者。该公司曾在1896年，刚刚在中央交易所推出了电源的“普通电池”制度。在那之前，一个人有手摇电话以提供足够的电力呼叫。一个连接可能仍然只能在给予该人的名义下提出要求达到一个电话接线员。这是强改变的原因。 强很快成为贝尔的强大竞争者。他在1901年引进了一个桌面拨号模型，这个模型在设计方面比贝尔的模型更加清晰。在1902年，他引进了一个带有磁盘拨号的墙面电话，这次与实际指孔，仍然只有170度左右在磁盘周围。到1905年，一个“长距离”手指孔已经被增加了。最后一个强的知名模型是在1907年。强的专利大概过期于1914年，之后他或他的公司再也没有听到过。直到1919年贝尔引进了拨号系统。当他们这样做，在拨号盘的周围手指孔被充分扩展了。 强发明的拨号系统直到1922年进入像纽约一样的大城市才成为主流。但是一旦作为规规范被确立，直到70年代它仍然是主要的电话技术。后按键式拨号在1963年被推出之后，强发明的最初的手指拨号系统作为“旋转的拨号系统”而知名。这是强怎样“让你的手指拨号”的。 埃姆斯椅LCW和DCW 1947 这些带有复合曲线座位，靠背和橡胶防震装置的成型胶合板椅是由查尔斯埃姆斯设计，在赫曼米勒家具公司生产的。 这个原始的概念是被查尔斯埃姆斯（1907—1978）和埃罗沙里宁（1910—1961）在1940年合作构想出来的。在1937年，埃姆斯成为克兰布鲁克学院实验设计部门的领头人，和沙里宁一起工作调查材料和家具。在这些努力下，埃姆斯发明了分成薄片和成型胶合板夹板，被称作埃姆斯夹板，在1941年收到了来自美国海军5000人的订单。查尔斯和他的妻子雷在他们威尼斯，钙的工作室及工厂和埃文斯产品公司的生产厂家一起生产了这批订单。 在1941年现代艺术博物馆，艾略特诺伊斯组织了一场比赛用以发现对现代生活富有想象力的设计师。奖项颁发给了埃姆斯和沙里宁他们的椅子和存储碎片，由包括埃德加考夫曼，大都会艺术博物馆的阿尔弗雷德，艾略特诺伊斯，马尔塞布鲁尔，弗兰克帕里什和建筑师爱德华达雷尔斯通的陪审团裁决。 这些椅子在1946年的现代艺术展览博物馆被展出，查尔斯埃姆斯设计的新的家具。当时，椅子只有三条腿，稳定性问题气馁了大规模生产。 早期的LCW（低木椅）和DWC（就餐木椅）设计有四条木腿在1946年第一次被埃文斯产品公司（埃姆斯的战时雇主）生产出来，被赫曼米勒家具公司分配。这些工具1946年被乔治纳尔逊为赫曼米勒购买，在1949年接手制造权。后来金属脚的愿景在1951年制作，包括LCW（低金属椅）和DWC（就餐金属椅）模型。配套的餐饮和咖啡桌也产生。这条线一直
Load and Ultimate Moment of Prestressed Concrete Action Under Overload-Cracking Load It has been shown that a variation in the external load acting on a prestressed beam results in a change in the location of the pressure line for beams in the elastic range.This is a fundamental principle of prestressed construction.In a normal prestressed beam,this shift in the location of the pressure line continues at a relatively uniform rate,as the external load is increased,to the point where cracks develop in the tension fiber.After the cracking load has been exceeded,the rate of movement in the pressure line decreases as additional load is applied,and a significant increase in the stress in the prestressing tendon and the resultant concrete force begins to take place.This change in the action of the internal moment continues until all movement of the pressure line ceases.The moment caused by loads that are applied thereafter is offset entirely by a corresponding and proportional change in the internal forces,just as in reinforced-concrete construction.This fact,that the load in the elastic range and the plastic range is carried by actions that are fundamentally different,is very significant and renders strength computations essential for all designs in order to ensure that adequate safety factors exist.This is true even though the stresses in the elastic range may conform to a recognized elastic design criterion. It should be noted that the load deflection curve is close to a straight line up to the cracking load and that the curve becomes progressively more curved as the load is increased above the cracking load.The curvature of the load-deflection curve for loads over the cracking load is due to the change in the basic internal resisting moment action that counteracts the applied loads,as described above,as well as to plastic strains that begin to take place in the steel and the concrete when stressed to high levels. In some structures it may be essential that the flexural members remain crack free even under significant overloads.This may be due to the structures’being exposed to exceptionally corrosive atmospheres during their useful life.In designing prestressed members to be used in special structures of this type,it may be necessary to compute the load that causes cracking of the tensile flange,in order to ensure that adequate safety against cracking is provided by the design.The computation of the moment that will cause cracking is also necessary to ensure compliance with some design criteria. Many tests have demonstrated that the load-deflection curves of prestressed beams are approximately linear up to and slightly in excess of the load that causes the first cracks in the tensile flange.(The linearity is a function of the rate at which the load is applied.)For this reason,normal elastic-design relationships can be used in computing the cracking load by simply determining the load that results in a net tensile stress in the tensile flange(prestress minus the effects of the applied loads)that is equal to the tensile strength of the concrete.It is customary to assume that the flexural tensile strength of the concrete is equal to the modulus of rupture of the
E---MARKETING (From:E--Marketing by Judy Strauss,Adel El--Ansary,Raymond Frost---3rd ed.1999 by Pearson Education pp .G4-G25.) As the growth of https://www.doczj.com/doc/4017668529.html, shows, some marketing principles never change.Markets always welcome an innovative new product, even in a crowded field of competitors ,as long as it provides customer value.Also,Google`s success shows that customers trust good brands and that well-crafted marketing mix strategies can be effective in helping newcomers enter crowded markets. Nevertheless, organizations are scrambling to determine how they can use information technology profitably and to understand what technology means for their business strategies. Marketers want to know which of their time-ested concepts will be enhanced by the Internet, databases,wireless mobile devices, and other technologies. The rapid growth of the Internet and subsequent bursting of the dot-com bubble has marketers wondering,"What next?" This article attempts to answer these questions through careful and systematic examination of successful e-mar-keting strategies in light of proven traditional marketing practices. （Sales Promotion;E--Marketing；Internet；Strategic Planning ） 1.What is E--Marketing E--Marketing is the application of a broad range of information technologies for: Transforming marketing strategies to create more customer value through more effective segmentation ,and positioning strategies；More efficiently planning and executing the conception, distribution promotion,and pricing of goods,services,and ideas;andCreating exchanges that satisfy individual consumer and organizational customers` objectives. This definition sounds a lot like the definition of traditional marketing. Another way to view it is that e-marketing is the result of information technology applied to traditional marketing. E-marketing affects traditional marketing in two ways. First,it increases efficiency in traditional marketing strategies.The transformation results in new business models that add customer value and/or increase company profitability.
forced concrete structure reinforced with an overviewRein Since the reform and opening up, with the national economy's rapid and sustained development of a reinforced concrete structure built, reinforced with the development of technology has been great. Therefore, to promote the use of advanced technology reinforced connecting to improve project quality and speed up the pace of construction, improve labor productivity, reduce costs, and is of great significance. Reinforced steel bars connecting technologies can be divided into two broad categories linking welding machinery and steel. There are six types of welding steel welding methods, and some apply to the prefabricated plant, and some apply to the construction site, some of both apply. There are three types of machinery commonly used reinforcement linking method primarily applicable to the construction site. Ways has its own characteristics and different application, and in the continuous development and improvement. In actual production, should be based on specific conditions of work, working environment and technical requirements, the choice of suitable methods to achieve the best overall efficiency. 1、steel mechanical link 1.1 radial squeeze link Will be a steel sleeve in two sets to the highly-reinforced Department with superhigh pressure hydraulic equipment (squeeze tongs) along steel sleeve radial squeeze steel casing, in squeezing out tongs squeeze pressure role of a steel sleeve plasticity deformation closely integrated with reinforced through reinforced steel sleeve and Wang Liang's Position will be two solid steel bars linked Characteristic: Connect intensity to be high, performance reliable, can bear high stress draw and pigeonhole the load and tired load repeatedly.
Interaction design Moggridge Bill Interaction design，Page 1-15 USA Art Press, 2008 Interaction design (IxD) is the study of devices with which a user can interact, in particular computer users. The practice typically centers on "embedding information technology into the ambient social complexities of the physical world."[1] It can also apply to other types of non-electronic products and services, and even organizations. Interaction design defines the behavior (the "interaction") of an artifact or system in response to its users. Malcolm McCullough has written, "As a consequence of pervasive computing, interaction design is poised to become one of the main liberal arts of the twenty-first century." Certain basic principles of cognitive psychology provide grounding for interaction design. These include mental models, mapping, interface metaphors, and affordances. Many of these are laid out in Donald Norman's influential book The Psychology of Everyday Things. As technologies are often overly complex for their intended target audience, interaction design aims to minimize the learning curve and to increase accuracy and efficiency of a task without diminishing usefulness. The objective is to reduce frustration and increase user productivity and satisfaction. Interaction design attempts to improve the usability and experience of the product, by first researching and understanding certain users' needs and then designing to meet and exceed them. (Figuring out who needs to use it, and how those people would like to use it.) Only by involving users who will use a product or system on a regular basis will designers be able to properly tailor and maximize usability. Involving real users, designers gain the ability to better understand user goals and experiences. (see also: User-centered design) There are also positive side effects which include enhanced system capability awareness and user ownership. It is important that the user be aware of system capabilities from an early stage so that expectations regarding functionality are both realistic and properly understood. Also, users who have been active participants in a product's development are more likely to feel a sense of ownership, thus increasing overall satisfa. Instructional design is a goal-oriented, user-centric approach to creating training and education software or written materials. Interaction design and instructional design both rely on cognitive psychology theories to focus on how users will interact with software. They both take an in-depth approach to analyzing the user's needs and goals. A needs analysis is often performed in both disciplines. Both, approach the design from the user's perspective. Both, involve gathering feedback from users, and making revisions until the product or service has been found to be effective. (Summative / formative evaluations) In many ways, instructional
Journal of Industrial Textiles https://www.doczj.com/doc/4017668529.html,/ Optimization of Parameters for the Production of Needlepunched Nonwoven Geotextiles Amit Rawal, Subhash Anand and Tahir Shah 2008 37: 341Journal of Industrial Textiles DOI: 10.1177/1528083707081594 The online version of this article can be found at: https://www.doczj.com/doc/4017668529.html,/content/37/4/341 Published by: https://www.doczj.com/doc/4017668529.html, can be found at:Journal of Industrial TextilesAdditional services and information for https://www.doczj.com/doc/4017668529.html,/cgi/alertsEmail Alerts: https://www.doczj.com/doc/4017668529.html,/subscriptionsSubscriptions: https://www.doczj.com/doc/4017668529.html,/journalsReprints.navReprints: https://www.doczj.com/doc/4017668529.html,/journalsPermissions.navPermissions: https://www.doczj.com/doc/4017668529.html,/content/37/4/341.refs.htmlCitations: - Mar 28, 2008Version of Record >>
外文文献： Risk Analysis of the International Construction Project By: Paul Stanford Kupakuwana Cost Engineering Vol. 51/No. 9 September 2009 ABSTRACT This analysis used a case study methodology to analyse the issues surrounding the partial collapse of the roof of a building housing the headquarters of the Standards Association of Zimbabwe (SAZ). In particular, it examined the prior roles played by the team of construction professionals. The analysis revealed that the SAZ’s traditional construction project was generally characterized by high risk. There was a clear indication of the failure of a contractor and architects in preventing and/or mitigating potential construction problems as alleged by the plaintiff. It was reasonable to conclude that between them the defects should have been detected earlier and rectified in good time before the partial roof failure. It appeared justified for the plaintiff to have brought a negligence claim against both the contractor and the architects. The risk analysis facilitated, through its multi-dimensional approach to a critical examination of a construction problem, the identification of an effective risk management strategy for future construction projects. It further served to emphasize the point that clients are becoming more demanding, more discerning, and less willing to accept risk without recompense. Clients do not want surprise, and are more likely to engage in litigation when things go wrong. KEY WORDS:Arbitration, claims, construction, contracts, litigation, project and risk The structural design of the reinforced concrete elements was done by consulting engineers Knight Piesold (KP). Quantity surveying services were provided by Hawkins, Leshnick & Bath (HLB). The contract was awarded to Central African Building Corporation (CABCO) who was also responsible for the provision of a specialist roof structure using patented “gang nail” roof
(文档含英文原文和中文翻译) 中英文翻译原文：
DESIGN and ENVIRONMENT Product design is the principal part and kernel of industrial design. Product design gives uses pleasure. A good design can bring hope and create new lifestyle to human. In spscificity,products are only outcomes of factory such as mechanical and electrical products,costume and so on.In generality,anything,whatever it is tangibile or intangible,that can be provided for a market,can be weighed with value by customers, and can satisfy a need or desire,can be entiled as products. Innovative design has come into human life. It makes product looking brand-new and brings new aesthetic feeling and attraction that are different from traditional products. Enterprose tend to renovate idea of product design because of change of consumer's lifestyle , emphasis on individuation and self-expression,market competition and requirement of individuation of product. Product design includes factors of society ,economy, techology and leterae humaniores. Tasks of product design includes styling, color, face processing and selection of material and optimization of human-machine interface. Design is a kind of thinking of lifestyle.Product and design conception can guide human lifestyle . In reverse , lifestyle also manipulates orientation and development of product from thinking layer.
毕业论文外文文献翻译 毕业设计（论文）题目关于企业内部环境绩效审计的研究翻译题目最高审计机关的环境审计活动 学院会计学院 专业会计学 姓名张军芳 班级09020615 学号09027927 指导教师何瑞雄
最高审计机关的环境审计活动 1最高审计机关越来越多的活跃在环境审计领域。特别是1993-1996年期间，工作组已检测到环境审计活动坚定的数量增长。首先，越来越多的最高审计机关已经活跃在这个领域。其次是积极的最高审计机关，甚至变得更加活跃：他们分配较大部分的审计资源给这类工作，同时出版更多环保审计报告。表1显示了平均数字。然而，这里是机构间差异较大。例如，环境报告的数量变化，每个审计机关从1到36份报告不等。 1996-1999年期间，结果是不那么容易诠释。第一，活跃在环境审计领域的最高审计机关数量并没有太大变化。“活性基团”的组成没有保持相同的：一些最高审计机关进入，而其他最高审计机关离开了团队。环境审计花费的时间量略有增加。二，但是，审计报告数量略有下降，1996年和1999年之间。这些数字可能反映了从量到质的转变。这个信号解释了在过去三年从规律性审计到绩效审计的转变（1994-1996年，20％的规律性审计和44％绩效审计;1997-1999：16％规律性审计和绩效审计54％）。在一般情况下，绩效审计需要更多的资源。我们必须认识到审计的范围可能急剧变化。在将来，再将来开发一些其他方式去测算人们工作量而不是计算通过花费的时间和发表的报告会是很有趣的。 在2000年，有62个响应了最高审计机关并向工作组提供了更详细的关于他们自1997年以来公布的工作信息。在1997-1999年，这62个最高审计机关公布的560个环境审计报告。当然，这些报告反映了一个庞大的身躯，可用于其他机构的经验。环境审计报告的参考书目可在网站上的最高审计机关国际组织的工作组看到。这里这个信息是用来给最高审计机关的审计工作的内容更多一些洞察。 自1997年以来，少数环境审计是规律性审计（560篇报告中有87篇，占16％）。大多数审计绩效审计（560篇报告中有304篇，占54％），或组合的规律性和绩效审计（560篇报告中有169篇，占30％）。如前文所述，绩效审计是一个广泛的概念。在实践中，绩效审计往往集中于环保计划的实施（560篇报告中有264篇，占47％），符合国家环保法律，法规的，由政府部门，部委和/或其他机构的任务给访问（560篇报告中有212篇，占38％）。此外，审计经常被列入政府的环境管理系统（560篇报告中有156篇，占28％）。下面的元素得到了关注审计报告：影响或影响现有的国家环境计划非环保项目对环境的影响;环境政策;由政府遵守国际义务和承诺的10％至20％。许多绩效审计包括以上提到的要素之一。 1本文译自：S. Van Leeuwen.(2004).’’Developments in Environmental Auditing by Supreme Audit Institutions’’ Environmental Management Vol. 33, No. 2, pp. 163–1721
外文翻译 原文 Marketing Material Source：Marketing Management Author：Philip Kotler Marketing Channels To reach a target market, the marketer uses three kinds of marketing channels. Communication channels deliver messages to and receive messages from target buyers. They include newspapers, magazines, radio, television, mail, telephone, billboards, posters, fliers, CDs, audiotapes, and the Internet. Beyond these, communications are conveyed by facial expressions and clothing, the look of retail stores, and many other media. Marketers are increasingly adding dialogue channels (e-mail and toll-free numbers) to counterbalance the more normal monologue channels (such as ads). The marketer uses distribution channels to display or deliver the physical product or service to the buyer or user. There are physical distribution channels and service distribution channels, which include warehouses, transportation vehicles, and various trade channels such as distributors, wholesalers, and retailers. The marketer also uses selling channels to effect transactions with potential buyers. Selling channels include not only the distributors and retailers but also the banks and insurance companies that facilitate transactions. Marketers clearly face a design problem in choosing the best mix of communication, distribution, and selling channels for their offerings. Supply Chain Whereas marketing channels connect the marketer to the target buyers, the supply chain describes a longer channel stretching from raw materials to components to final products that are carried to final buyers. For example, the supply chain for women’s purses starts with hides, tanning operations, cutting operations, manufacturing, and the marketing channels that bring products to customers. This supply chain represents a value delivery system. Each company captures only a certain percentage of the total value generated by the supply chain. When a company acquires competitors or moves upstream or downstream, its aim is