金融学专业外文翻译原文

金融学专业外文翻译原文
金融学专业外文翻译原文

金融衍生工具和流通量的上升

流通的社会结构性成因

激增的短期投机资本,通过这种承受风险的衍生物的流通而变得具体和富有生气,似乎从正在进行的全球经济的基本社会结构的变革中反映,放大和升华(Eatwell and Taylor 2002)。上述现象更是使重要性日益增强的流动性与金融机构及工具的发展特别是在流动性资本方面的关系得到了不断的发展(Pryke and Allen2000)。这似乎是现代资本主义的内在动力强迫他们趋向于追逐更高的,更具全球范围意义的生产标准,那似乎是在产生那样一种能够连接自身成为社会结构价值的,逐渐上升的复杂标准。虽然在当时并没有发现,从二十世纪七十年代开始欧美工业生产的潜力已经耗尽了(Brenner 1998),需要一定的空间来补救和修复(Harvey 2000; James 2001)。许多行业需要探索新的途径来对更边缘的地区进行一体化(特别是南亚地区),以此来支撑受过度的产品生产和过多的资本积累强制驱动的,从而引发的关键性矛盾。正如斯皮罗所说(1999),欧美资本主义所产生和吸收的资本量(尤其是欧佩克成员国),在大部分现有的工业部门,已经超过了它能有利润的进行资本再投资的需求量。因此哈维(1982)所评论说“如果平衡被重新恢复,需要一个过程,即通过运行生产系统消除过剩的资本,那么资本过度积累的趋势将被自动抵消。”

宗主国响应的一个关键性方面是欧美公司全球性的重组,开始把大量工业原材料的生产和原件的制造外包给那些较先进的发展中国家的较发达地区。通常是南亚,特别是中国是这次重组的主要受惠者(Singh2002)。那些先进地区边缘的内陆地区也包括整个国家,比如巴基斯坦,也成为了原材料和手工劳动产品(例如:纺织品)的外包中心。尽管还有一些国家,特别是虽然不是只在沙哈拉以南的非洲地区,他们参加这个过程仅仅给人以边缘的和偶然的感觉。正如邦德(2001)的分析师认为,像莫桑比克和乍得这样的国家,似乎被全球经济所孤立除了那些最受剥削的方面。

生产的这一改组接连产生了那些传统解决办法不能解决的问题(Hoogvelt 1997)。与先前的国际贸易的形式形成对比,这种从二十世纪七十年代开始的重

1

组活动,引发并导致了生产过程在基本投入阶段的破裂(Jones 2000)。契约化外包服务(在给定的时间范围内提供产品的协议)的增值和机构化,使得那些公司必须去解决的风险增加了,并且风险被重新配置。新的、表面上看来,更不容易控制的风险,例如政治风险、交易对手风险和货币风险,即将出现。为了规避这些风险,正如希勒(1993)评论的那样,金融机构开始为企业客户开发衍生物及其市场。为了使那些衍生物变得富有效率,它们的市场需要是易变现的(具有流动性的),使公司负责人能够依照他们的需求来购买和销售。流动性需求连同这些市场自我扩张的结构,为吸收那些在宗主国过度积累的资本提供了新的出路和机会,孕育新的机构,比如对冲基金和新的银行业部门,那专门研究如何对管理投机资本。而且,因为资产池的不断扩大,及金融技术人员塑造出新的衍生工具合约来扩大投机资本的范围和最大限度的发挥投机资本的杠杆作用,加之新技术的运用使得在全球范围内不分昼夜的进行交易成为可能,这种资本的经济力量正在以指数方式增长。那些数字确实的让人惊奇:每年进行交易的金融衍生工具的价值已经接近一百万亿美元,而绝大多数在未受管制的场外交易市场(OTC)。根据美国财政部(2003),那些银行集团企业,JP摩根大通,目前已经有一个衍生成的有根基的能够控制超过两万亿美元外国货币的阵地,超过绝大多数国家的国民生产总值。因此生产的最重要的产物是迅速的成为连通性物流的生产活动,通信网络,金融工具和技术,用来援助和扩大其流通性。

投机资本,金融衍生品和风险

根据提示,金融衍生品是这个循环社会结构的一个组成部分,具有三个相互关联的因素。三个因素中首先是投机资本,这是一个巨大的,任意的,非生产导向性的和不断的扩大资金池移动性的,游动的,存在于绝大多数投资银行(例如:高盛),私自拥有对冲基金(e.g. LTCM)和特别是那些最大公司的财务部门(例如:通用电气财务公司)手中。这些银行、基金和部门坐落在文化和精神上,要不然的话就是欧洲和美国的地缘政治景观。第二个因素是金融衍生产品及其市场。这套联动体系在许多方面参与全球市场,其中最有意义的是扩大了这些产品的销售。这是重要的,因为金融衍生产品是投机资本在全球市场上所运用的最重要的工具。金融衍生产品在本质上是基于货币价格(即利率)或国家间货币的关系进行变动。从市场角度出发,它们似乎是必要的和自然的,因为它们被与在全球化

当中其核心作用的流动性有关的风险所激发。最后一个因素是最近铸造成的和具有决定性的风险概念:是新的,因为风险被从不确定的和限定的实体领域所抽取出来,因为它构成了这种产品和衍生物的价格。这些因素的构造和组合构成了金融流通文化的分子结构。虽然三者本身多不是新的,他们的组合,重新定义,制度化和技术放大在世界经济的运作方式上产生了根本性的转变,以流通的范围不断的扩大和自主性不断的增强为特点。

因此衍生金融工具是重要的,因为它们是市场上承担投机资本的有效形式(Saber1999),因为它们是流通最终的结构形态。

全球化危机。投机资本采用这种形式,因为衍生工具将客观的各种风险统一为单一的工具,那些来自合并风险的几乎无限制的杠杆效应和被用于对冲和投机的能力。核心是客观化的过程,因为衍生产品不具备具体的形态,但是社会想象的对象利用语言所具有的分类能力将那些有特色的和有独立关系的联系起来。因此客观化在这里是指通过当代金融界所表现出来的过程,像一个没有指挥的的管弦乐队一样运作,使一个社会的复杂融合具体化,政治的和经济的关系变为一个单一的可辨认的标的(衍生合约),然后似乎是不依赖于这些关系,因为这些关系不是那些标的或工具明显表现的一个部分。衍生工具看起来似乎是一个简单的合约,它允许买者和卖者进行投机和套期保值,虽然,就像它分析的展示那样,这将会变得清楚,这仅仅是一个相当复杂现象的表现。

出处:爱德华?里布马;本杰明?李.经济和社会34卷,2005年8月3号.

3

计算机专业毕业设计说明书外文翻译(中英对照)

Talking about security loopholes Richard S. Kraus reference to the core network security business objective is to protect the sustainability of the system and data security, This two of the main threats come from the worm outbreaks, hacking attacks, denial of service attacks, Trojan horse. Worms, hacker attacks problems and loopholes closely linked to, if there is major security loopholes have emerged, the entire Internet will be faced with a major challenge. While traditional Trojan and little security loopholes, but recently many Trojan are clever use of the IE loophole let you browse the website at unknowingly were on the move. Security loopholes in the definition of a lot, I have here is a popular saying: can be used to stem the "thought" can not do, and are safety-related deficiencies. This shortcoming can be a matter of design, code realization of the problem. Different perspective of security loo phole s In the classification of a specific procedure is safe from the many loopholes in classification. 1. Classification from the user groups: ● Public loopholes in the software category. If the loopholes in Windows, IE loophole, and so on. ● specialized software loophole. If Oracle loopholes, Apach e,

金融学专业外文翻译---对简便银行的简单见解

中文3696字 本科毕业论文外文翻译 出处:Infosys Strategic Vision 原文: Insights from Banking Simple By Ashok Vemuri Introduction “A simpler way of banking.We treat with you respect. No extraneous features. No hidden fees.” For the unini tiated, this is the mantra of BankSimple, a Brooklyn-based startup which has positioned itself as a consumer-friendly alternative to traditional banks. BankSimple pushes a message of user experience—sophisticated personal finance analytics, a single “do-it-all” card, superior customer service, and no overdraft fees.Though branchless and primarily online-based, BankSimple is also planning to provide some traditional customer service touches, including phone support and mail-in deposits. Interestingly, BankSimple will also likely not be a bank—at least not in the technical, FDIC sense of the word. Rather, BankSimple’s strategy is to be a front-end focused on the customer experience. The back-end core “bank” component will be FDIC-insured partner banks. Unfettered by years of IT investments and entrenched applications, BankSimple’s team has the freedom to build an innovative, user-friendly online interface, customer service program, and the associated mobile and social bells and whistles that more and more consumers are demanding. One way to look at it is as a wrapper insulating the consumer from the accounting, compliance, and technology challenges that many banks face. Like personal finance sites https://www.360docs.net/doc/f59749157.html, and Wesabe before it, BankSimple is looking to tap into a perceived gap between what major banks provide and what consumers want. A recent survey by ForeSee Results and Forbes found that consumers view online banking as more satisfying than banking done offline. Though good news for the industry as a whole, the survey also found that the five largest banks in the country scored the lowest in the study. Cheaper and more customer friendly, digital banking is the future—but many consumers are finding it is better done with credit unions, community banks, and (down-the-road) startups like BankSimple. As you read, significant investments are being made by banks to improve their online, mobile, and IVR customer-friendliness. Major banks are embracing these channels, and customer satisfaction will likely improve over time. Even so, startups like Bank- Simple should be viewed as a learning opportunity. Their ideas are disruptive and often highlight pain points that need to be addressed. BankSimple’s first two stated philosophies are a good place to start: “A simpler way of banking” and “We treat you with respect.”

ASP外文翻译原文

https://www.360docs.net/doc/f59749157.html, https://www.360docs.net/doc/f59749157.html, 是一个统一的 Web 开发模型,它包括您使用尽可能少的代码生成企业级 Web 应用程序所必需的各种服务。https://www.360docs.net/doc/f59749157.html, 作为 .NET Framework 的一部分提供。当您编写 https://www.360docs.net/doc/f59749157.html, 应用程序的代码时,可以访问 .NET Framework 中的类。您可以使用与公共语言运行库 (CLR) 兼容的任何语言来编写应用程序的代码,这些语言包括 Microsoft Visual Basic、C#、JScript .NET 和 J#。使用这些语言,可以开发利用公共语言运行库、类型安全、继承等方面的优点的https://www.360docs.net/doc/f59749157.html, 应用程序。 https://www.360docs.net/doc/f59749157.html, 包括: ?页和控件框架 ?https://www.360docs.net/doc/f59749157.html, 编译器 ?安全基础结构 ?状态管理功能 ?应用程序配置 ?运行状况监视和性能功能 ?调试支持 ?XML Web services 框架 ?可扩展的宿主环境和应用程序生命周期管理 ?可扩展的设计器环境 https://www.360docs.net/doc/f59749157.html, 页和控件框架是一种编程框架,它在 Web 服务器上运行,可以动态地生成和呈现 https://www.360docs.net/doc/f59749157.html, 网页。可以从任何浏览器或客户端设备请求 https://www.360docs.net/doc/f59749157.html, 网页,https://www.360docs.net/doc/f59749157.html, 会向请求浏览器呈现标记(例如 HTML)。通常,您可以对多个浏览器使用相同的页,因为 https://www.360docs.net/doc/f59749157.html, 会为发出请求的浏览器呈现适当的标记。但是,您可以针对诸如 Microsoft Internet Explorer 6 的特定浏览器设计https://www.360docs.net/doc/f59749157.html, 网页,并利用该浏览器的功能。https://www.360docs.net/doc/f59749157.html, 支持基于 Web 的设备(如移动电话、手持型计算机和个人数字助理 (PDA))的移动控件。

毕业设计外文翻译附原文

外文翻译 专业机械设计制造及其自动化学生姓名刘链柱 班级机制111 学号1110101102 指导教师葛友华

外文资料名称: Design and performance evaluation of vacuum cleaners using cyclone technology 外文资料出处:Korean J. Chem. Eng., 23(6), (用外文写) 925-930 (2006) 附件: 1.外文资料翻译译文 2.外文原文

应用旋风技术真空吸尘器的设计和性能介绍 吉尔泰金,洪城铱昌,宰瑾李, 刘链柱译 摘要:旋风型分离器技术用于真空吸尘器 - 轴向进流旋风和切向进气道流旋风有效地收集粉尘和降低压力降已被实验研究。优化设计等因素作为集尘效率,压降,并切成尺寸被粒度对应于分级收集的50%的效率进行了研究。颗粒切成大小降低入口面积,体直径,减小涡取景器直径的旋风。切向入口的双流量气旋具有良好的性能考虑的350毫米汞柱的低压降和为1.5μm的质量中位直径在1米3的流量的截止尺寸。一使用切向入口的双流量旋风吸尘器示出了势是一种有效的方法,用于收集在家庭中产生的粉尘。 摘要及关键词:吸尘器; 粉尘; 旋风分离器 引言 我们这个时代的很大一部分都花在了房子,工作场所,或其他建筑,因此,室内空间应该是既舒适情绪和卫生。但室内空气中含有超过室外空气因气密性的二次污染物,毒物,食品气味。这是通过使用产生在建筑中的新材料和设备。真空吸尘器为代表的家电去除有害物质从地板到地毯所用的商用真空吸尘器房子由纸过滤,预过滤器和排气过滤器通过洁净的空气排放到大气中。虽然真空吸尘器是方便在使用中,吸入压力下降说唱空转成比例地清洗的时间,以及纸过滤器也应定期更换,由于压力下降,气味和细菌通过纸过滤器内的残留粉尘。 图1示出了大气气溶胶的粒度分布通常是双峰形,在粗颗粒(>2.0微米)模式为主要的外部来源,如风吹尘,海盐喷雾,火山,从工厂直接排放和车辆废气排放,以及那些在细颗粒模式包括燃烧或光化学反应。表1显示模式,典型的大气航空的直径和质量浓度溶胶被许多研究者测量。精细模式在0.18?0.36 在5.7到25微米尺寸范围微米尺寸范围。质量浓度为2?205微克,可直接在大气气溶胶和 3.85至36.3μg/m3柴油气溶胶。

毕业设计外文翻译原文.

Optimum blank design of an automobile sub-frame Jong-Yop Kim a ,Naksoo Kim a,*,Man-Sung Huh b a Department of Mechanical Engineering,Sogang University,Shinsu-dong 1,Mapo-ku,Seoul 121-742,South Korea b Hwa-shin Corporation,Young-chun,Kyung-buk,770-140,South Korea Received 17July 1998 Abstract A roll-back method is proposed to predict the optimum initial blank shape in the sheet metal forming process.The method takes the difference between the ?nal deformed shape and the target contour shape into account.Based on the method,a computer program composed of a blank design module,an FE-analysis program and a mesh generation module is developed.The roll-back method is applied to the drawing of a square cup with the ˉange of uniform size around its periphery,to con?rm its validity.Good agreement is recognized between the numerical results and the published results for initial blank shape and thickness strain distribution.The optimum blank shapes for two parts of an automobile sub-frame are designed.Both the thickness distribution and the level of punch load are improved with the designed blank.Also,the method is applied to design the weld line in a tailor-welded blank.It is concluded that the roll-back method is an effective and convenient method for an optimum blank shape design.#2000Elsevier Science S.A.All rights reserved. Keywords:Blank design;Sheet metal forming;Finite element method;Roll-back method

计算机专业外文文献翻译6

外文文献翻译(译成中文2000字左右): As research laboratories become more automated,new problems are arising for laboratory managers.Rarely does a laboratory purchase all of its automation from a single equipment vendor. As a result,managers are forced to spend money training their users on numerous different software packages while purchasing support contracts for each. This suggests a problem of scalability. In the ideal world,managers could use the same software package to control systems of any size; from single instruments such as pipettors or readers to large robotic systems with up to hundreds of instruments. If such a software package existed, managers would only have to train users on one platform and would be able to source software support from a single vendor. If automation software is written to be scalable, it must also be flexible. Having a platform that can control systems of any size is far less valuable if the end user cannot control every device type they need to use. Similarly, if the software cannot connect to the customer’s Laboratory Information Management System (LIMS) database,it is of limited usefulness. The ideal automation software platform must therefore have an open architecture to provide such connectivity. Two strong reasons to automate a laboratory are increased throughput and improved robustness. It does not make sense to purchase high-speed automation if the controlling software does not maximize throughput of the system. The ideal automation software, therefore, would make use of redundant devices in the system to increase throughput. For example, let us assume that a plate-reading step is the slowest task in a given method. It would make that if the system operator connected another identical reader into the system, the controller software should be able to use both readers, cutting the total throughput time of the reading step in half. While resource pooling provides a clear throughput advantage, it can also be used to make the system more robust. For example, if one of the two readers were to experience some sort of error, the controlling software should be smart enough to route all samples to the working reader without taking the entire system offline. Now that one embodiment of an ideal automation control platform has been described let us see how the use of C++ helps achieving this ideal possible. DISCUSSION C++: An Object-Oriented Language Developed in 1983 by BjarneStroustrup of Bell Labs,C++ helped propel the concept of object-oriented programming into the mainstream.The term ‘‘object-oriented programming language’’ is a familiar phrase that has been in use for decades. But what does it mean? And why is it relevant for automation software? Essentially, a language that is object-oriented provides three important programming mechanisms:

金融学专业外文翻译(中英对照、翻译专业修改好了的)

论文题目:关于巴塞尔II:新巴塞尔资本协议的影响 学院名称:财经学院专业班级:金融0814班学生姓名:王庆贺 外文题目:Dealing with Basel II: the impact of the New Basel Capital Accord 出处:Balance Sheet,2003,Vol.11(No.4) 作者:Thomas Garside and Jens Bech 译文: 关于巴塞尔II:新巴塞尔资本协议的影响 托马斯·加赛德和杰尼斯·伯克 摘要:国际监管机构在2003年完成新资本协议,银行决定在2006年底执行这个协议。巴塞尔协议是对全球银行业改革的监管。在本文中,我们回顾新巴塞尔资本协议内容以及一些我们所期望对欧洲银行业发生的重要影响。正如在第一届巴塞尔协议修正案(Basel I)中,我们得出结论,新巴塞尔协议不仅对持有资本额的数量做了规定,还对银行业的战略格局进行展望。 关键词:银行,流动性,监管,风险管理 新巴塞尔资本协议的新规则 巴塞尔委员会虽然只是公布了三分之一,但这很可能是协商的最后新资本协议(Basel II)文件。这项建议如获通过,将会深刻地改变银行的偿付能力的方式,监管机构监管银行风险管理实施过程和银行必须对市场参与者公布的风险信息量,经过讨论会,巴塞尔委员会预计将在2003年底发布的新资本协议的最后草案。 目前的巴塞尔资本协议(Basel I)对达到加强国际金融体系的稳定的既定目标已经有了显著成效,通过在不同国家持续应用本协议的同时,增加了资本水平,创造了一个更公平的竞争领域。总的来说,目前的全球一级资本的平均水平从1993年的约6%升至8%,此外,巴塞尔资本协议已经应用于100多个国家,远远超过最初的预期。 尽管实现其最初目标的成效很明显,很显然,对于巴塞尔我有一些意想不到的不

中国的对外贸易外文翻译及原文

外文翻译 原文 Foreign T rade o f China Material Source:W anfang Database Author:Hitomi Iizaka 1.Introduction On December11,2001,China officially joined the World T rade Organization(WTO)and be c a me its143rd member.China’s presence in the worl d economy will continue to grow and deepen.The foreign trade sector plays an important andmultifaceted role in China’s economic development.At the same time, China’s expanded role in the world economy is beneficial t o all its trading partners. Regions that trade with China benefit from cheaper and mor e varieties of imported consumer goods,raw materials and intermediate products.China is also a large and growing export market.While the entry of any major trading nation in the global trading system can create a process of adjustment,the o u t c o me is fundamentally a win-win situation.In this p aper we would like t o provide a survey of the various institutions,laws and characteristics of China’s trade.Among some of the findings, we can highlight thefollowing: ?In2001,total trade to gross domestic pr oduct(GDP)ratio in China is44% ?In2001,47%of Chinese trade is processed trade1 ?In2001,51%of Chinese trade is conduct ed by foreign firms in China2 ?In2001,36%of Chinese exports originate from Gu an gdon g province ?In2001,39%of China’s exports go through Hong Kong to be re-exported elsewhere 2.Evolution of China’s Trade Regime Equally remarkable are the changes in the commodity composition of China’s exports and imports.Table2a shows China’s annu al export volumes of primary goods and manufactured goods over time.In1980,primary goods accounted for 50.3%of China’s exports and manufactured goods accounted for49.7%.Although the share of primary good declines slightly during the first half of1980’s,it remains at50.6%in1985.Since then,exports of manufactured goods have grown at a much

计算机专业外文翻译

专业外文翻译 题目JSP Technology Conspectus and Specialties 系(院)计算机系 专业计算机科学与技术 班级 学生姓名 学号 指导教师 职称讲师 二〇一三年五月十六日

JSP Technology Conspectus and Specialties The JSP (Java Server Pages) technology is used by the Sun micro-system issued by the company to develop dynamic Web application technology. With its easy, cross-platform, in many dynamic Web application programming languages, in a short span of a few years, has formed a complete set of standards, and widely used in electronic commerce, etc. In China, the JSP now also got more extensive attention; get a good development, more and more dynamic website to JSP technology. The related technologies of JSP are briefly introduced. The JSP a simple technology can quickly and with the method of generating Web pages. Use the JSP technology Web page can be easily display dynamic content. The JSP technology are designed to make the construction based on Web applications easier and efficient, and these applications and various Web server, application server, the browser and development tools work together. The JSP technology isn't the only dynamic web technology, also not the first one, in the JSP technology existed before the emergence of several excellent dynamic web technologies, such as CGI, ASP, etc. With the introduction of these technologies under dynamic web technology, the development and the JSP. Technical JSP the development background and development history In web brief history, from a world wide web that most of the network information static on stock transactions evolution to acquisition of an operation and infrastructure. In a variety of applications, may be used for based on Web client, look no restrictions. Based on the browser client applications than traditional based on client/server applications has several advantages. These benefits include almost no limit client access and extremely simplified application deployment and management (to update an application, management personnel only need to change the program on a server, not thousands of installation in client applications). So, the software industry is rapidly to build on the client browser multilayer application. The rapid growth of exquisite based Web application requirements development of

金融学毕业论文外文翻译中英文全

Improve the concept of financial supervision in rural areas1 Xun Qian Farmers in China's vast population, has some large-scale production of the farmers, but also survival-oriented farmers, huge differences between the financial needs of rural finance intermediation makes complex, together with agriculture itself is the profit low, natural and market risks high risk decision to weak agricultural industry characteristics, resulting in the cost of rural financial transactions is far higher than the city, also decided to organize the rural financial system in terms of operation or in the market has its own special characteristics. 20 years of financial reform, financial development while the Chinese city made impressive achievements, but the rural finance is the entire financial system is still the weakest link. Insufficient supply of rural finance, competition is not sufficient, farmers and agricultural enterprises in getting loans and other issues is also very prominent, backward rural financial system can no longer effectively support the development of modern agriculture or the transformation of traditional agriculture and the building of new socialist countryside, which to improve the rural financial supervision new topic. China's rural financial regulatory problems (A) the formation of China's financial regulatory system had "a line three commission " (People's Bank, the Securities Regulatory Commission, Insurance Regulatory Commission and the Banking Regulatory Commission) financial regulatory structure. Bank These stringent requirements, different management and diversification of monitoring has its positive role, but it also had some negative effects. First, inefficient supervision, supervision of internal consumption of high costs, limited financial industry business development and innovation space. Second, the regulatory agencies, regulatory bodies and the information asymmetry between central banks, banking, securities, and insurance mechanisms of coordination between regulatory bodies are not perfect. Information between central banks and regulatory agencies is difficult to share, is difficult to create effective monitoring force. Basically between the various 1American Journal of Agricultural Economics,2009.

英文翻译与英文原文.陈--

翻译文献:INVESTIGATION ON DYNAMIC PERFORMANCE OF SLIDE UNIT IN MODULAR MACHINE TOOL (对组合机床滑台动态性能的调查报告) 文献作者:Peter Dransfield, 出处:Peter Dransfield, Hydraulic Control System-Design and Analysis of TheirDynamics, Springer-Verlag, 1981 翻译页数:p139—144 英文译文: 对组合机床滑台动态性能的调查报告 【摘要】这一张纸处理调查利用有束缚力的曲线图和状态空间分析法对组合机床滑台的滑动影响和运动平稳性问题进行分析与研究,从而建立了滑台的液压驱动系统一自调背压调速系统的动态数学模型。通过计算机数字仿真系统,分析了滑台产生滑动影响和运动不平稳的原因及主要影响因素。从那些中可以得出那样的结论,如果能合理地设计液压缸和自调背压调压阀的结构尺寸. 本文中所使用的符号如下: s1-流源,即调速阀出口流量; S el—滑台滑动摩擦力 R一滑台等效粘性摩擦系数: I1—滑台与油缸的质量 12—自调背压阀阀心质量 C1、c2—油缸无杆腔及有杆腔的液容; C2—自调背压阀弹簧柔度; R1, R2自调背压阀阻尼孔液阻, R9—自调背压阀阀口液阻 S e2—自调背压阀弹簧的初始预紧力; I4, I5—管路的等效液感 C5、C6—管路的等效液容: R5, R7-管路的等效液阻; V3, V4—油缸无杆腔及有杆腔内容积; P3, P4—油缸无杆腔及有杆腔的压力 F—滑台承受负载, V—滑台运动速度。本文采用功率键合图和状态空间分折法建立系统的运动数学模型,滑台的动态特性可以能得到显著改善。

外文翻译原文

204/JOURNAL OF BRIDGE ENGINEERING/AUGUST1999

JOURNAL OF BRIDGE ENGINEERING /AUGUST 1999/205 ends.The stress state in each cylindrical strip was determined from the total potential energy of a nonlinear arch model using the Rayleigh-Ritz method. It was emphasized that the membrane stresses in the com-pression region of the curved models were less than those predicted by linear theory and that there was an accompanying increase in ?ange resultant force.The maximum web bending stress was shown to occur at 0.20h from the compression ?ange for the simple support stiffness condition and 0.24h for the ?xed condition,where h is the height of the analytical panel.It was noted that 0.20h would be the optimum position for longitudinal stiffeners in curved girders,which is the same as for straight girders based on stability requirements.From the ?xed condition cases it was determined that there was no signi?cant change in the membrane stresses (from free to ?xed)but that there was a signi?cant effect on the web bend-ing stresses.Numerical results were generated for the reduc-tion in effective moment required to produce initial yield in the ?anges based on curvature and web slenderness for a panel aspect ratio of 1.0and a web-to-?ange area ratio of 2.0.From the results,a maximum reduction of about 13%was noted for a /R =0.167and about 8%for a /R =0.10(h /t w =150),both of which would correspond to extreme curvature,where a is the length of the analytical panel (modeling the distance be-tween transverse stiffeners)and R is the radius of curvature.To apply the parametric results to developing design criteria for practical curved girders,the de?ections and web bending stresses that would occur for girders with a curvature corre-sponding to the initial imperfection out-of-?atness limit of D /120was used.It was noted that,for a panel with an aspect ratio of 1.0,this would correspond to a curvature of a /R =0.067.The values of moment reduction using this approach were compared with those presented by Basler (Basler and Thurlimann 1961;Vincent 1969).Numerical results based on this limit were generated,and the following web-slenderness requirement was derived: 2 D 36,500a a =1?8.6?34 (1) ? ??? t R R F w ?y where D =unsupported distance between ?anges;and F y =yield stress in psi. An extension of this work was published a year later,when Culver et al.(1973)checked the accuracy of the isolated elas-tically supported cylindrical strips by treating the panel as a unit two-way shell rather than as individual strips.The ?ange/web boundaries were modeled as ?xed,and the boundaries at the transverse stiffeners were modeled as ?xed and simple.Longitudinal stiffeners were modeled with moments of inertias as multiples of the AASHO (Standard 1969)values for straight https://www.360docs.net/doc/f59749157.html,ing analytical results obtained for the slenderness required to limit the plate bending stresses in the curved panel to those of a ?at panel with the maximum allowed out-of-?atness (a /R =0.067)and with D /t w =330,the following equa-tion was developed for curved plate girder web slenderness with one longitudinal stiffener: D 46,000a a =1?2.9 ?2.2 (2) ? ? ? t R f R w ?b where the calculated bending stress,f b ,is in psi.It was further concluded that if longitudinal stiffeners are located in both the tension and compression regions,the reduction in D /t w will not be required.For the case of two stiffeners,web bending in both regions is reduced and the web slenderness could be de-signed as a straight girder panel.Eq.(1)is currently used in the ‘‘Load Factor Design’’portion of the Guide Speci?cations ,and (2)is used in the ‘‘Allowable Stress Design’’portion for girders stiffened with one longitudinal stiffener.This work was continued by Mariani et al.(1973),where the optimum trans-verse stiffener rigidity was determined analytically. During almost the same time,Abdel-Sayed (1973)studied the prebuckling and elastic buckling behavior of curved web panels and proposed approximate conservative equations for estimating the critical load under pure normal loading (stress),pure shear,and combined normal and shear loading.The linear theory of shells was used.The panel was simply supported along all four edges with no torsional rigidity of the ?anges provided.The transverse stiffeners were therefore assumed to be rigid in their directions (no strains could be developed along the edges of the panels).The Galerkin method was used to solve the governing differential equations,and minimum eigenvalues of the critical load were calculated and presented for a wide range of loading conditions (bedding,shear,and combined),aspect ratios,and curvatures.For all cases,it was demonstrated that the critical load is higher for curved panels over the comparable ?at panel and increases with an increase in curvature. In 1980,Daniels et al.summarized the Lehigh University ?ve-year experimental research program on the fatigue behav-ior of horizontally curved bridges and concluded that the slen-derness limits suggested by Culver were too severe.Equations for ‘‘Load Factor Design’’and for ‘‘Allowable Stress Design’’were developed (respectively)as D 36,500a =1?4?192(3)? ?t R F w ?y D 23,000a =1?4 ?170 (4) ? ? t R f w ?b The latter equation is currently used in the ‘‘Allowable Stress Design’’portion of the Guide Speci?cations for girders not stiffened longitudinally. Numerous analytical and experimental works on the subject have also been published by Japanese researchers since the end of the CURT project.Mikami and colleagues presented work in Japanese journals (Mikami et al.1980;Mikami and Furunishi 1981)and later in the ASCE Journal of Engineering Mechanics (Mikami and Furunishi 1984)on the nonlinear be-havior of cylindrical web panels under bending and combined bending and shear.They analyzed the cylindrical panels based on Washizu’s (1975)nonlinear theory of shells.The governing nonlinear differential equations were solved numerically by the ?nite-difference method.Simple support boundary condi-tions were assumed along the curved boundaries (top and bot-tom at the ?ange locations)and both simple and ?xed support conditions were used at the straight (vertical)boundaries.The large displacement behavior was demonstrated by Mi-kami and Furunishi for a range of geometric properties.Nu-merical values of the load,de?ection,membrane stress,bend-ing stress,and torsional stress were obtained,but no equations for design use were presented.Signi?cant conclusions include that:(1)the compressive membrane stress in the circumfer-ential direction decreases with an increase in curvature;(2)the panel under combined bending and shear exhibits a lower level of the circumferential membrane stress as compared with the panel under pure bending,and as a result,the bending moment carried by the web panel is reduced;and (3)the plate bending stress under combined bending and shear is larger than that under pure bending.No formulations or recommendations for direct design use were made. Kuranishi and Hiwatashi (1981,1983)used the ?nite-ele-ment method to demonstrate the elastic ?nite displacement be-havior of curved I-girder webs under bending using models with and without ?ange rigidities.Rotation was not allowed (?xed condition)about the vertical axis at the ends of the panel (transverse stiffener locations).Again,the nonlinear distribu-

相关文档
最新文档