机械设计制造及其自动化 外文翻译 外文文献 英文文献 有限元分析系统的发展现状与展望

专业：机械设计制造及其自动化

外文出处： Department of Mechanical Engineering &

(用外文写)

Biomechanics The University of Texas at San Antonio 附件1：外文资料翻译译文

The finite element analysis system development present situation and

prospect

Ravichandra Patchigolla and Yesh P. Singh

Along with the development of modern science and technology, people are constantly build more fast traffic tools, larger buildings, the more big

span Bridges, the more power generator sets and more precision mechanical equipment. All these require engineer in the designing phase can accurately

predict products and engineering technical performance, need to structure

strength and static and dynamic temperature field, flow field, electromagnetic field and seepage analysis of technical parameters. For

example analysis and calculation of the high-rise buildings and large span

bridge during an earthquake, look at the implications will happen destructive accidents; Analysis and calculation of the temperature field

of nuclear reactors, determine whether reasonable heat transfer and cooling system; Analysis of fluid dynamics in turbine blade, in order to improve

the operation parameters of efficiency. These can be summed up in solving

physical control problems partial differential equations is often impossible. In recent years in the computer technology and the numerical

Analysis method supports developed under Finite Element Analysis (FEA)

method and Finite Element, order is to solve the complicated engineering

Analysis and calculation problem which provides an effective way. Our

country of the ninth five-year plan period in promoting CAD technology, mechanical industry from the prevalence rate of large and medium-sized enterprises CAD 20% of the five-year "end" raised to current 70%. Along with

the enterprise CAD widely applied, Engineering and technical personnel, and already gradually dump board will focus in how to optimize the design, improve product quality, Engineering and Computer Aided Engineering analysis (CAE, Computer software and applicants Engineering) method will be the key technical factors. In engineering practice, finite element analysis software and the integrated application of CAD system make the design level occurred a qualitative leap, mainly displays in the following aspects: to increase the design function, reduce design cost;

? shorten design and analysis of cycle;

? increase the reliability of products and engineering;

? adopting the optimization design, reduce material consumpti on or cost; ? in products manufacturing or engineering construction advance found potential problem;

? simulate various test plan to reduce the time and money;

? mechanical accident analysis, found out the cause of the accident.

In promoting CAD technology today, from his bike to the space shuttle, all the design manufacture is inseparable from the finite element calculation and analysis, in the engineering design and analysis FEA will get more and more extensive attention. Below is the San Francisco bay bridge seismic response analysis of finite element analysis model.

Development direction and significant progress in early 20th century world at the end of the 1950s and early 1960s invested a lot of manpower and material resources development with powerful features of finite element analysis program. One of the most famous is by NASA (NASA) in 1965 entruststhe American computing science company and bel air system company developed the NASTRAN finite element analysis system. This system have been developed dozens of version, is the world's largest, the strongest function finite element analysis system. From then to now, the world's research institutions and universities are developing a batch of smaller but flexible, price lower special or general finite element analysis software, mainly in Germany PAFEC

ASKA, British, French SYSTUS, American ABQUS, ADINA, ANSYS, BERSAFE, BOSOR COSMOS, ELAS, MARC, STARDYNE etc products with. Today's international development of the FEA method and software shows the following some trends features:

1 from the pure structure mechanics calculation development to solve many problems of physical field finite element analysis method (from structured matrix analysis, evolved gradually extended to board, shell and entity etc continuum solid mechanics analysis, the practice has proved it is a very efficient numerical analysis method. And theoretically has also proof, as long as the unit used for solving the object of discrete small enough income can be enough solution in precision value approach. So in recent years has progressed to finite element method of fluid mechanics, temperature field, electric conduction, magnetic field, seepage and problems solving calculation of acoustic, and recently developed to solve several interdisciplinary problem. For example when air flows through a high tower, and the deformation of the tower in turn affect deformation airflow flow... This needs with solid mechanics and fluid dynamic finite element analysis results cross, the so-called "iteration fluidsolid coupled" problem.

2 by solving linear engineering problems progressed to the analysis nonlinear problems with the development of science and technology, linear theory has far can't meet the design requirements. For example the high-rise building and construction industry, the emergence of large-span suspension bridge is asked to consider structure of large displacement and large strain etc geometrically nonlinear; Aerospace and power engineering of high temperature parts existing thermal deformation and thermal stress, also want to consider material nonlinear problem; Such as plastic, rubber and composite materials, etc. Various kinds of new material appears, only on linear computation theory would not be sufficient to solve the problems of using nonlinear finite element algorithm, only to solve. As is known to all, nonlinear numerical calculation is very complex, it involves a lot of special

mathematics problems and operation skill, hard as general engineering technicians hands. Therefore in recent years abroad some company has spent a lot of manpower and investment and development such as MARC, ABQUS and ADINA specializes in solving nonlinear problems such as the finite element analysis software, and widely used in engineering practice. These software in common is efficient nonlinear solver and rich and practical nonlinear CaiLiaoKu.

3 enhance visual lead modeling and rear data processing functions early finite element analysis software research emphasis on solving method is a new high efficiency and high accuracy unit. Along with the gradual improvement method of numerical analysis, particularly the rapid development of computer operation speed, the whole calculation system for solving operations less time, and data preparation and operation result performance problem is getting more and more outstanding. In today's engineering workstation, solving a contains 10 million equation with the finite element model requires only a few minutes. But if use manual way to build the model, and then the calculation result is handling large amounts of time needs a few weeks. It is no exaggeration to say, engineers in analysis and calculation have an engineering problem more than 80% of the energy is spent on data preparation and analysis of the results. So now almost all the commercial finite element program system has powerful lead modeling and rear data processing module. In emphasizing "visual" today, many procedures are established to very User friendly GUI (with), little User with visual graphic User can quickly way grid directly generate finite element analysis, automatic dividing the data, and required the amount of calculation results consolidation deformation figure, equivalent to cloud, facilitate extremum distribution list of search and required data output.

4 and seamless integration of CAD software of finite element analysis system today with general another characteristic is the integration of CAD software in use namely, complete with CAD software components and parts after the

modelling design, automatically generating finite element mesh and calculate, if the analysis results do not comply with the design requirements are calculated to restart modelling and, until satisfaction, thus greatly improve the design level and efficiency. Today, engineers can in the integration of CAD and FEA software environment quickly solve a in the past can deal with complex engineering analysis problem. So today's all commercial finite element system developed and famous auto-producers CAD software (for example Pro/e, SolidEdge, SolidWorks Unigraphics, Bentley and AutoCAD, IDEAS, etc) interface.

5 in the development of the Wintel platform of early finite element analysis software are basically in large and medium-sized computers (mainly Mainframe) on the development or operation, and later developed to Engineering workstations (EWS, Engineering WorkStation) as a platform, their common characteristic is all adopt the UNIX operating system. The PC has made the application of computer fundamental changes happened on her desk, the engineer eager to finish complex engineering analysis dreams to become a reality. But early PC using 16-bit CPU and DOS operating system, the memory data block limited public, so was the size of the calculation model should not exceed 1 000 order equation. Microsoft Windows operating system and the Intel Pentium processor 32-bit for will launch the PC provides necessary for finite element analysis software and hardware of the support platform. Therefore the internationally famous finite element program research and development institutions have their software shifted to the Wintel platform. The table below lists the ADINA V7.3 version with the PC's Windows NT environment and SGI workstation and four engineering example calculated the time needed to solve. It shows the latest high-grade PC already and the solving ability of neck-and-neck EWS cheap.

Table V7.3 edition ADINA running time of several machines comparison Characteristics of computational problems

Equation several NEQ

Running time (in seconds)

PentiumII450MHZ

PentiumIII450MHZ

Engineering workstations

Nonlinear 3d contact

(calculation step)

51159

219

188

219

Linear static analysis

58707

262

234

249

Dynamic analysis frequency calculation

31205

311

258

287

Three-dimensional flow analysis

36162

218

183

208

For large and medium-sized computers and EWS in developed on finite element program shifted to PE machine, often need to adopt the Hummingbird company Exceed a simulation software. The result more troublesome, and can't make full use of the PC software and hardware resources. So recently some companies, such as IDEAS, ADINA and R&D began in Windows platform development

finite element program, called "Native Windows" versions, and on their PCS in the Linux operating system environment development of finite element program packages.

Domestic development situation and prospects of the United States in 1979 SAP5 linear structure static, dynamic analysis program to introduce transplant success, domestic application lifted the universal finite element program to the climax of the analysis and calculation of engineering problems. The climax continued until 1981 ADINA nonlinear structural analysis program has been introduced, at that time many cannot solve engineering problems are solved. Everybody also began to understand the finite element analysis program is really engineer for the analysis of the application of computer the important tool. But was limited to domestic large and medium-sized computers seldom, only about the hangzhou steam turbine factory Siemens7738 and shenyang blower factory IBM4310 installation of the program, so the user calculate very inconvenient and expensive. PC's emergence and its performance miraculously enhance, for transplantation and development PC version of the finite element program provides the necessary operation platform. Say the development of domestic FEA is always fuss around PC platforms. In domestic development more successful and have more users (100 more) finite element analysis system has dalian university of technology FIFEX95, the department of engineering force of Beijing university of science and engineering mechanics SAP84, China academy of machinery science MAS5.0 and hangzhou automation technology institute MFEP4. 0, etc. But as described above, foreign many famous finite element analysis company has shrugged off to a PC platform from years of development for keen, change the FEA program developers development domestic PC version, and should no longer has the advantage from the following several aspects effort: 1 research and development solution of a solid mechanics and interdisciplinary FEA program after decades of research and development, and to solve the finite element method and the solid mechanics software has

more mature, now the forefront of research problem is fluid dynamics, compressible and non-compressible fluid flow from solid mechanics and interdisciplinary problem. No similar functions to the domestic commercial software, so foreign software, they sell very expensive. In order to break the monopoly situation, we must develop have independent copyright, used to analyze the fluid is not solid mechanics and interdisciplinary software. Because fluid mechanics problem is far more complex than solid and rarely have a ready-made software can reference, therefore requires a lot of manpower and funds. It must have countries and large enterprise groups to support.

2 development with Chinese characteristics automatic modeling technology and GUI development modeling technology and the investment than mere the foregoing subject to GUI much less, but can greatly improve the performance of the FEA software and user acceptance, thus plays twice the result with half the effort. The domestic many people in this respect did a lot of work, but it was the PC graphics support environment is limited, therefore the development effect be not all very ideal. Windows provides for OpenGL graphics standard, PC application in visual graphics technology to developing GUI provides powerful tools. Today's international OpenGL is generally recognized high-performance graphics and interactive visual processing standards, apply it to the 3d graphics software developed by the endearment of professional and technical personnel in the world, now dominant computer companies have adopted this standard. As mentioned, in recent years the FEA program has cast abroad some simulation software, directly on Windows platform development finite element program. Hangzhou automation technology institute 1997-1999 using OpenGL graphics standard and the corresponding Visual c + + programming tools, such as in PC successfully developed a set of visualization finite element program packages. It can directly through the "menu", "the window", "dialog box" and "icon" visual graphic pictures and symbols such as the operation,

automatic establish finite element analysis model in an interactive method, and the calculation results of the type of realizing, and visualization processor can greatly improve the efficiency of limited the analysis and accuracy, also facilitate the user study and control.

3 and has the independent copyright in front of CAD software integration today had been told, an important feature of the finite element method and seamless integration of CAD software. As the development of our country proper motion, firstly, we must consider the FEA program and our independent copyright CAD software integration. Because the finite element analysis is mainly used in shape more complex components, so want to and with three-dimensional modeling functions and CAD software integration, which makes the design and analysis of combine closely, as a whole.

2：外文原文（复印件）

有限元分析系统的发展现状与展望

随着现代科学技术的发展，人们正在不断建造更为快速的交通工具、更大规模的建筑物、更大跨度的桥梁、更大功率的发电机组和更为精密的机械设备。这一切都要求工程师在设计阶段就能精确地预测出产品和工程的技术性能，需要对结构的静、动力强度以及温度场、流场、电磁场和渗流等技术参数进行分析计算。例如分析计算高层建筑和大跨度桥梁在地震时所受到的影响，看看是否会发生破坏性事故；分析计算核反应堆的温度场，确定传热和冷却系统是否合理；分析涡轮机叶片内的流体动力学参数，以提高其运转效率。这些都可归结为求解物理问题的控制偏微分方程式往往是不可能的。近年来在计算机技术和数值分析方法支持下发展起来的有限元分析（FEA，Finite Element Analysis）方法则为解决这些复杂的工程分析计算问题提供了有效的途径。我国在"九五"计划期间大力推广CAD技术，机械行业大中型企业CAD的普及率从"八五"末的20%提高到目前的70%。随着企业CAD应用的普及，工程技术人员已逐步甩掉图板，而将主要精力投身如何优化设计，提高工程和产品质量，计算机辅助工程分析（CAE，Computer Aided Engineering）方法和软件将成为关键的技术要素。在工程实践中，有限元分析软件与CAD系统的集成应用使设计水平发生了质的飞跃，主要表现在以下几个方面：增加设计功能，减少设计

成本；

?缩短设计和分析的循环周期；

?增加产品和工程的可靠性；

?采用优化设计，降低材料的消耗或成本；

?在产品制造或工程施工前预先发现潜在的问题；

?模拟各种试验方案，减少试验时间和经费；

?进行机械事故分析，查找事故原因。

在大力推广CAD技术的今天，从自行车到航天飞机，所有的设计制造都离不开有限元分析计算，FEA在工程设计和分析中将得到越来越广泛的重视。下图是美国旧金山海湾大桥地震响应计算的有限元分析模型。

发展方向及重大进展国际上早20世纪在50年代末、60年代初就投入大量的人力和物力开发具有强大功能的有限元分析程序。其中最为著名的是由美国国家宇航局（NASA）在1965年委托美国计算科学公司和贝尔航空系统公司开发的NASTRAN 有限元分析系统。该系统发展至今已有几十个版本，是目前世界上规模最大、功能最强的有限元分析系统。从那时到现在，世界各地的研究机构和大学也发展了一批规模较小但使用灵活、价格较低的专用或通用有限元分析软件，主要有德国的ASKA、英国的PAFEC、法国的SYSTUS、美国的ABQUS、ADINA、ANSYS、BERSAFE、BOSOR、COSMOS、ELAS、MARC和STARDYNE等公司的产品。当今国际上FEA方法和软件发展呈现出以下一些趋势特征：

1 从单纯的结构力学计算发展到求解许多物理场问题有限元分析方法最早是从结构化矩阵分析发展而来，逐步推广到板、壳和实体等连续体固体力学分析，实践证明这是一种非常有效的数值分析方法。而且从理论上也已经证明，只要用于离散求解对象的单元足够小，所得的解就可足够逼近于精确值。所以近年来有限元方法已发展到流体力学、温度场、电传导、磁场、渗流和声场等问题的求解计算，最近又发展到求解几个交叉学科的问题。例如当气流流过一个很高的铁塔产生变形，而塔的变形又反过来影响到气流的流动……这就需要用固体力学和流体动力学的有限元分析结果交叉迭代求解，即所谓"流固耦合"的问题。

2 由求解线性工程问题进展到分析非线性问题随着科学技术的发展，线性理论已经远远不能满足设计的要求。例如建筑行业中的高层建筑和大跨度悬索桥的出

现，就要求考虑结构的大位移和大应变等几何非线性问题；航天和动力工程的高温部件存在热变形和热应力，也要考虑材料的非线性问题；诸如塑料、橡胶和复合材料等各种新材料的出现，仅靠线性计算理论就不足以解决遇到的问题，只有采用非线性有限元算法才能解决。众所周知，非线性的数值计算是很复杂的，它涉及到很多专门的数学问题和运算技巧，很难为一般工程技术人员所掌握。为此近年来国外一些公司花费了大量的人力和投资开发诸如MARC、ABQUS和ADINA等专长于求解非线性问题的有限元分析软件，并广泛应用于工程实践。这些软件的共同特点是具有高效的非线性求解器以及丰富和实用的非线性材料库。

3 增强可视化的前置建模和后置数据处理功能早期有限元分析软件的研究重点在于推导新的高效率求解方法和高精度的单元。随着数值分析方法的逐步完善，尤其是计算机运算速度的飞速发展，整个计算系统用于求解运算的时间越来越少，而数据准备和运算结果的表现问题却日益突出。在现在的工程工作站上，求解一个包含10万个方程的有限元模型只需要用几十分钟。但是如果用手工方式来建立这个模型，然后再处理大量的计算结果则需用几周的时间。可以毫不夸张地说，工程师在分析计算一个工程问题时有80%以上的精力都花在数据准备和结果分析上。因此目前几乎所有的商业化有限元程序系统都有功能很强的前置建模和后置数据处理模块。在强调"可视化"的今天，很多程序都建立了对用户非常友好的GUI （Graphics User Interface）,使用户能以可视图形方式直观快速地进行网格自动划分，生成有限元分析所需数据，并按要求将大量的计算结果整理成变形图、等值分布云图，便于极值搜索和所需数据的列表输出。

4 与CAD软件的无缝集成当今有限元分析系统的另一个特点是与通用CAD软件的集成使用即,在用CAD软件完成部件和零件的造型设计后，自动生成有限元网格并进行计算，如果分析的结果不符合设计要求则重新进行造型和计算，直到满意为止，从而极大地提高了设计水平和效率。今天，工程师可以在集成的CAD和FEA软件环境中快捷地解决一个在以前无法应付的复杂工程分析问题。所以当今所有的商业化有限元系统商都开发了和著名的CAD软件（例如Pro/ENGINEER、Unigraphics、SolidEdge、SolidWorks、IDEAS、Bentley和AutoCAD等）的接口。

5 在Wintel平台上的发展早期的有限元分析软件基本上都是在大中型计算机（主要是Mainframe）上开发和运行的，后来又发展到以工程工作站（EWS，Engineering WorkStation）为平台，它们的共同特点都是采用UNIX操作系统。PC

机的出现使计算机的应用发生了根本性的变化，工程师渴望在办公桌上完成复杂工程分析的梦想成为现实。但是早期的PC机采用16位CPU和DOS操作系统，内存中的公共数据块受到限制，因此当时计算模型的规模不能超过1万阶方程。Microsoft Windows操作系统和32位的Intel Pentium处理器的推出为将PC机用于有限元分析提供了必需的软件和硬件支撑平台。因此当前国际上著名的有限元程序研究和发展机构都纷纷将他们的软件移值到Wintel平台上。下表列出了用ADINA V7.3版在PC机的Windows NT环境和SGI工作站上同时计算4个工程实例所需要的求解时间。从中可以看出最新高档PC机的求解能力已和中低档的EWS不相上下。

表 ADINA V7.3版几种机器上的运行时间比较

计算问题的特征

方程数NEQ

运行时间（秒）

PentiumII450MHZ

PentiumIII450MHZ

工程工作站

非线性三维接触

（计算一步）

51159

219

188

219

线性静力分析

58707

262

234

249

动力分析频率计算

31205

311

258

287

三维流动分析

36162

218

183

208

为了将在大中型计算机和EWS上开发的有限元程序移值到PE机上，常常需要采用Hummingbird公司的一个仿真软件Exceed。这样做的结果比较麻烦，而且不能充分利用PC机的软硬件资源。所以最近有些公司，例如IDEAS、ADINA和R&D开始在Windows平台上开发有限元程序，称作"Native Windows"版本，同时还有在PC 机上的Linux操作系统环境中开发的有限元程序包。

国内发展情况和前景1979年美国的SAP5线性结构静、动力分析程序向国内引进移植成功，掀起了应用通用有限元程序来分析计算工程问题的高潮。这个高潮一直持续到1981年ADINA非线性结构分析程序引进，一时间许多一直无法解决的工程难题都迎刃而解了。大家也都开始认识到有限元分析程序的确是工程师应用计算机进行分析计算的重要工具。但是当时限于国内大中型计算机很少，大约只有杭州汽轮机厂的Siemens7738和沈阳鼓风机厂的IBM4310安装有上述程序，所以用户算题非常不方便，而且费用昂贵。PC机的出现及其性能奇迹般的提高，为移植和发展PC版本的有限元程序提供了必要的运行平台。可以说国内FEA软件的发展一直是围绕着PC平台做文章。在国内开发比较成功并拥有较多用户（100家以上）的有限元分析系统有大连理工大学工程力学系的FIFEX95、北京大学力学与科学工程系的SAP84、中国农机科学研究院的MAS5.0和杭州自动化技术研究院的MFEP4. 0等。但正如上面所述，国外很多著名的有限元分析公司已经从前些年对PC平台不屑一顾转变为热衷发展，对国内FEA程序开发者来说发展PC版本不再具有优势，而应该从下面几方面加以努力：

1 研究开发求解非固体力学和交叉学科的FEA程序经过几十年的研究和发展，用于求解固体力学的有限元方法和软件已经比较成熟，现在研究的前沿问题是流体动力学、可压缩和不可压缩流体的流动等非固体力学和交叉学科的问题。由于国内没有类似功能的商品化软件，所以国外的软件就卖得非常贵。为了破这种垄断局面，我们必须发展有自主版权、用于分析流体等非固体力学和交叉学科的软件。因为流

体力学问题远比固体复杂得多，而且很少有现成的软件可以借鉴，所以需要投入大量的人力和经费。这就必须有国家和大型企业集团来支持。

2 开发具有中国特色的自动建模技术和GUI开发建模技术和GUI的投入比前述课题要少得多，但却可以大大提高FEA软件的性能和用户接受程度，从而起到事半功倍的效果。国内不少人在这方面做了很多工作，但是由于当时PC机上的图形支撑环境有限，所以开发的效果都不甚理想。Windows中提供了OpenGL图形标准，为在PC机上应用可视化图形技术开发GUI提供了强有力的工具。OpenGL是当今国际上公认的高性能图形和交互式视景处理标准，应用它开发出来的三维图形软件深受专业技术人员的钟爱，目前世界上占主导地位的计算机公司都采用了这一标准。正如前面所述，近年来国外有的FEA程序已抛开仿真软件，直接在Windows平台上开发有限元程序。杭州自动化技术研究院1997-1999年采用OpenGL图形标准和相应的Visual C++等编程工具，在PC机上成功地开发了一套可视化有限元程序包。它能直观地通过对"菜单"、"窗口"、"对话框"和"图标"等可视图形画面和符号的操作，自动建立有限元分析模型，并以交互方法式实现计算结果的可视化处理，因而可大大提高有限昂分析的效率和精确性，也便于用户学习和掌握。

3 与具有我国自主版权的CAD软件集成前面已经讲过，当今有限元方法的一个重要特点是和CAD软件的无缝集成。作为我国自行开发的FEA程序，首先要考虑和我国自主版权的CAD软件集成。因为有限元分析主要用于形状比较复杂的零部件，所以要和具有三维造型功能和CAD软件集成，使设计和分析紧密结合、融为一体。

英文文献翻译

中等分辨率制备分离的 快速色谱技术 W. Clark Still,* Michael K a h n , and Abhijit Mitra Departm(7nt o/ Chemistry, Columbia Uniuersity,1Veu York, Neu; York 10027 ReceiLied January 26, 1978 我们希望找到一种简单的吸附色谱技术用于有机化合物的常规净化。这种技术是适于传统的有机物大规模制备分离，该技术需使用长柱色谱法。尽管这种技术得到的效果非常好，但是其需要消耗大量的时间，并且由于频带拖尾经常出现低复原率。当分离的样本剂量大于1或者2g时，这些问题显得更加突出。近年来，几种制备系统已经进行了改进，能将分离时间减少到1-3h，并允许各成分的分辨率ΔR f≥（使用薄层色谱分析进行分析）。在这些方法中，在我们的实验室中，媒介压力色谱法1和短柱色谱法2是最成功的。最近，我们发现一种可以将分离速度大幅度提升的技术，可用于反应产物的常规提纯，我们将这种技术称为急骤色谱法。虽然这种技术的分辨率只是中等（ΔR f≥），而且构建这个系统花费非常低，并且能在10-15min内分离重量在的样本。4 急骤色谱法是以空气压力驱动的混合介质压力以及短柱色谱法为基础，专门针对快速分离，介质压力以及短柱色谱已经进行了优化。优化实验是在一组标准条件5下进行的，优化实验使用苯甲醇作为样本，放在一个20mm*5in.的硅胶柱60内，使用Tracor 970紫外检测器监测圆柱的输出。分辨率通过持续时间（r）和峰宽（w,w/2）的比率进行测定的（Figure 1），结果如图2-4所示，图2-4分别放映分辨率随着硅胶颗粒大小、洗脱液流速和样本大小的变化。

中英文文献翻译-加工中心数控技术

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零售企业营销策略中英文对照外文翻译文献

零售企业营销策略中英文对照外文翻译文献(文档含英文原文和中文翻译)

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旅游管理专业论文外文文献翻译

外文资料译文及原文 译文(一) 消费者体验旅游和品牌的结合 米契尔罗伯特 定义消费者体验旅游 制造工厂参观，公司博物馆和公司访客中心表现为被不同名字已知的观光事业片段：制造业观光事业，工业的吸引、工业的观光事业和工业的遗产观光事业。在每一个描述性的长期的共同目标是在消费者学习品牌，其运作，生产过程，历史和历史意义的时候建立一个消费者和品牌之间的纽带。有人建议在这里CET代表一个统一的主题的旅游。这个术语捕捉消费者的消费能力发现更多关于他们所消费的品牌，而制造商可以在与该工厂的客人接触的30-120分钟时间里建立与这些消费者更密切的关系。 参与的品牌 品牌经理寻求解决在三个层次消费者的需求： （1）功能（对消费者提供解决问题的办法）; （2）符号（提供心理欲望满意度）; （3）经历（提供感官快乐，品种，认知，刺激） CET可以通过视觉地介绍品牌，运作，生产工艺，历史和历史意义加强消费者和品牌之间的纽带。这种纽带可以被看作是个人品牌参与和品牌忠诚度的提高。认知参与反映了消费者对产品的兴趣（或学习更多）。CET可以通过刺激消费者对于品牌和生产过程的想象提高消费者的认知水平。此外，积极口碑沟通刺激满足旅客可能会比其他形式的促销更可信。 缺乏现有的直接研究关注 迄今为止，CET已经在行销文学中受到一点注意。米契尔和米契尔（2001年）对此内容这种的旅游网站进行了评估。此外，这些相同的作者已经评估食物和饮料工业中的现象（米契尔和米契尔，2000年），非营利部门（米契尔和米契尔，2001年b），和整体经济（米契尔等， 2001）。米契尔和米契尔（2002）为学者提出了格式，用来评估在当地的服务领域这些设施的地方利益。该主题通常包括对整合营销的简要讨论，但已收到直接研究的关注很有限。

计算机网络-外文文献-外文翻译-英文文献-新技术的计算机网络

New technique of the computer network Abstract The 21 century is an ages of the information economy, being the computer network technique of representative techniques this ages, will be at very fast speed develop soon in continuously creatively, and will go deep into the people's work, life and study. Therefore, control this technique and then seem to be more to deliver the importance. Now I mainly introduce the new technique of a few networks in actuality live of application. keywords Internet Network System Digital Certificates Grid Storage 1. Foreword Internet turns 36, still a work in progress Thirty-six years after computer scientists at UCLA linked two bulky computers using a 15-foot gray cable, testing a new way for exchanging data over networks, what would ultimately become the Internet remains a work in progress. University researchers are experimenting with ways to increase its capacity and speed. Programmers are trying to imbue Web pages with intelligence. And work is underway to re-engineer the network to reduce Spam (junk mail) and security troubles. All the while threats loom: Critics warn that commercial, legal and political pressures could hinder the types of innovations that made the Internet what it is today. Stephen Crocker and Vinton Cerf were among the graduate students who joined UCLA professor Len Klein rock in an engineering lab on Sept. 2, 1969, as bits of meaningless test data flowed silently between the two computers. By January, three other "nodes" joined the fledgling network.

机械类数控车床外文翻译外文文献英文文献车床.doc

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