中英文中英文文献翻译-为适应预测磨损计算模型
流体力学中英文对照外文翻译文献
中英文对照外文翻译(文档含英文原文和中文翻译)14选择的材料取决于于高流动速度降解或材料由于疲劳，腐蚀，磨损和气蚀故障糜烂一次又一次导致泵运营商成本高昂的问题。
这可能通过仔细选择材料的性能以避免在大多数情况下发生。
一两个原因便可能导致错误的材料选择：（1）泵输送的腐蚀性液体的性质没有清楚地指定（或未知），或（2），由于成本的原因（竞争压力），使用最便宜的材料。
泵部件的疲劳，磨损，空化攻击的严重性和侵蚀腐蚀与流速以指数方式增加，但应用程序各种材料的限制，不容易确定。
它们依赖于流速度以及对介质的腐蚀性泵送和浓度夹带的固体颗粒，如果有的话。
另外，交变应力诱导通过压力脉动和转子/定子相互作用力（RSI）真的不能进行量化。
这就是为什么厚度的叶片，整流罩和叶片通常从经验和工程判断选择。
材料的本讨论集中在流之间的相互作用现象和物质的行为。
为此，在某些背景信息腐蚀和经常使用的材料，被认为是必要的，但是一个综合指南材料的选择显然是超出了本文的范围。
在这一章中方法开发出促进系统和一致方法选择材料和分析材料的问题领域。
四个标准有关，用于选择材料暴露于高流动速度：1.疲劳强度（通常在腐蚀环境），由于高的速度在泵本身与高压脉动，转子/定子的相互作用力和交变应力。
2.腐蚀诱导高的速度，特别是侵蚀腐蚀。
3.气蚀，由于已广泛在章讨论。
4.磨耗金属损失造成的流体夹带的固体颗粒。
磨损和汽蚀主要是机械磨损机制，它可以在次，被腐蚀的钢筋。
与此相反，腐蚀是一种化学金属，泵送的介质，氧和化学试剂之间的反应。
该反应始终存在- 即使它是几乎察觉。
最后，该叶轮尖端速度可以通过液压力或振动和噪声的限制。
14.1叶轮和扩散的疲劳性骨折可避免的叶轮叶片，整流罩或扩散器叶片的疲劳断裂施加领域的状态;它们很少观察到。
在高负荷的泵，无视基本设计规则或生产应用不足的医疗服务时，这种类型的伤害仍然是有时会遇到。
的主要原因在静脉或罩骨折包括：•过小的距离（间隙B或比D3*= D3/ D2）叶轮叶片之间扩散器叶片（表10.2）。
知识产权论文中英文对照外文翻译文献
中英文对照外文翻译文献1外文参考文献译文the well-known trademarks and dilute anti-diluted First, well-known trademarks SummaryWell-known trademarks is a long-term use, in the market enjoy a high reputation, known for the relevant public and by certain procedures that the trademark. Since the "Paris Convention" was first introduced the concept of well-known trademarks, the well-known trademarks for special protection legislation has become the world trend.Paris Convention stipulates: all of the members were identified as the well-known trade marks, or registered First, the first to ban others, and the other is to prohibit the use of others with identical or similar logo. Trips further provides: 1, the Paris Convention for the special protection and extension of the services of well-known trademarks, 2, the scope of protection does not extend to prohibit similar goods or services with the well-known trademarks for use on the same or similar logo, 3, on how to That a well-known trademarks in principle a simple requirement.National legislation on the practice, the well-known trade marks that standards vary, often based on specific trade mark promotion of public awareness of related areas, logo merchandise sales and the scope of national interests, and other factors identified. From an international treaty to protect the well-known trademarks mind, that well-known trade marks and protection of well-known trade marks are closely linked.Second, the well-known trademarks protected modeOn the protection of the main trademarks of relative and absolute protectionism two models.The former refers to ban others with well-known trademarks identical or similar trademark with the trademark owner the same or similar industries in the registration or use of similar goods in non-use of the same or similar trademarks is permitted, "the Paris Convention "That is, relative to protectionism.While the latter refers to ban others in any industry, including the well-known trade mark goods with different or similar to those in the industry to register with the well-known trade marks and the use of the same or similar trademarks, TRIPS agreement that is taken by the expansion of the absolute protectionism.In simple economic form, as specified by the trade mark goods at a single, specific trade mark goods and the link between more closely. With, a valuable well-known trademarks have been more and more use of different types of commodities, which are among the types of goods on the property may be totally different, in a trademark associated with the commodity groups and the relative weakening of trade marks Commodity producers and the relative isolation. Not well-known trademarks such as cross-category protection and allow others to register, even if the goods obvious differences, the public will still be in the new goods and reputable well-known trademarks to establish a link between people that the goods may be well-known trademark, the new commodities , Or the well-known trademarks of goods and people between the existence of a legal, organizational or business association, thus leading to the misuse of consumers purchase. The rapid development of the commodity today, the relative protectionism has not improved the protection of the public and well-known trademark owner's interests.In view of this, in order to effectively prevent the reputation of well-known trademarks, and the identification of significant features and advertising value by the improper use of the damage, many countries on the implementation of a well-known trademarks is protectionism, which prohibits the use of any products on the same or with the well-known trademarks Similar to the trademark.TRIPS Agreement Article 16, paragraph 3 states: Paris Convention 1967 text, in principle, applicable to the well-known trademarks and logos of the commodities or services are not similar goods or services, if not similar goods or services on the use of the trademark will be Suggest that the goods or services with the well-known trademarks on a link exists, so that the interests of all well-known trademarks may be impaired.Third, the well-known trademarks dilutedThe protection of trademark rights, there are mainly two: one for the confusion theory, a theory for desalination.The main traditional trademark protection for trade marks the difference between functional design, and its theoretical basis for the theory of confusion. In summary, which is to ensure that the trademark can be identification, confirmation and different goods or services different from the significant features, to avoid confusion, deception and E Wu, the law gives first use of a person or persons registered with exclusive rights, which prohibits any Without the permission of the rights to use may cause confusion among consumers in the same or similar trademarks. Clearly, the traditional concept of trademark protection, to stop "the possibility of confusion" is the core of trademark protection.With the socio-economic development and commercialization of the continuous improvement of the degree, well-known trademarks by the enormous implication for the growing commercial value have attracted the attention of people. Compared with ordinary marks, bearing well-known trademarks by the significance and meaning beyond the trademark rights to the general, and further symbol of product quality and credit, contains a more valuable business assets - goodwill. Well-known trade mark rights of people to use its excellent reputation of leading the way in the purchasing power, instead of the use of trademarks to distinguish between different products and producers.When the mark beyond the role of this feature to avoid confusion, then, this factor is obviously confused and can not cover everything, and other factors become as important as or more important. Thus, in theory confusion on the basis of further development of desalination theory.Trademark Dilution (dilution), also known as trademark dilution, is one of trademark infringement theory. "Watered down", according to the U.S. "anti-federal trademark law dilute" means "regardless of well-known trade mark rights and theothers between the existence of competition, or existence of confusion, misunderstanding or the possibility of deception, reduce and weaken the well-known trademarks Its goods or services and the identification of significant capacity of the act. " In China, some scholars believe that "refers to dilute or weaken gradually weakened consumer or the public will be trademarks of the commercial sources with a specific link between the ability." Trademark faded and that the main theory is that many market operators have Using well-known trademarks of the desire of others, engage in well-known trademarks should be to prevent others from using its own unique identification of special protection.1927, Frank • Si Kaite in the "Harvard Law reviews" wrote the first trademark dilute theory. He believes that people should not only be trademarks of others prohibit the use of the mark, he will compete in the commodity, and should prohibit the use of non-competitive goods on. He pointed out: the real role of trade marks, not distinguish between goods operators, but satisfied with the degree of difference between different commodities, so as to promote the continuous consumer purchase. From the basic function of trademarks, trade mark used in non-competitive goods, their satisfaction with regard to the distinction between the role of different commodities will be weakened and watered down. Trademarks of the more significant or unique, to the public the impression that the more deeply, that is, should be restricted to non-compete others in the use of goods or services.Since then, the Intellectual Property Rights Branch of the American Bar Association Chairman Thomas • E • Si Kaite Smith on the theory made a fu rther elaboration and development. He said: "If the courts allow or laissez-faire 'Rolls Royce' restaurants, 'Rolls-Royce' cafeteria, 'Rolls-Royce' pants, 'Rolls-Royce' the candy, then not 10 years, ' Rolls-Royce 'trademark owners will no longer have the world well-known trademarks. "Si Kaite in accordance with the theory of well-known trade marks have faded because of the effect of non-rights holders with well-known trademarks in the public mind the good image of well-known trademarks will be used in non-competitivegoods, so as to gradually weaken or reduce the value of well-known trademarks, That is, by the well-known trademarks have credibility. Trademark tag is more significant or unique characteristics, which in the public mind the impression that the more deep, more is the need for increased protection, to prevent the well-known trade marks and their specific goods was the link between the weakening or disappearance.In practice, trademarks diluted share a wide range of operating methods, such as:A well-known trademarks of others will still use as a trademark, not only in the use of the same, similar to the goods or services. For example, household appliances, "Siemens" trademark as its own production of the furniture's trademark.2. To other people's well-known trademarks as their corporate name of the component. Such as "Haier" trademark for the name of his restaurant.3. To the well-known trademarks of others as the use of domain names. For example, watches trademark "OMEGA" registered the domain name for themselves ().4. To the well-known trademarks of others as a commodity and decorating use.5. Will be others as well-known trade marks of goods or services using the common name. For example, "Kodak" interpreted as "film, is a camera with photographic material", or "film, also known as Kodak,……" This interpretation is also the mark of the water down. If the "Kodak" ignored the trademark owner, after a period of time, people will Kodak film is, the film is Kodak. In this way, the Kodak film-related goods has become the common name, it as a trademark by a significant, identifiable on limbo. The public well-known Jeep (Jeep), aspirin (Aspirin), freon (Freon), and so was the registration of foreign goods are due to improper use and management and the protection of poor, evolved into similar products common name, Thus lost its trademark logo features.U.S. "anti-diluted Federal trademark law" before the implementation of the Federal Court of Appeal through the second from 1994 to 1996 case, identified thefollowing violations including the Trademark Dilution: (1) vague, non-means as others in similar goods not on Authorized the use of a trademark so that the sales of goods and reduce the value of trademarks or weakened (2) pale, that is because of violations related to the quality, or negative, to demonize the acts described a trademark goods may be caused to others The negative effects of the situation, (3) to belittle, or improperly changed, or derogatory way to describe a trade mark case.The majority of our scholars believe that the well-known trademarks diluted There are two main forms: watered down and defaced. The so-called dilute the people will have no right to use the same or similar trademark with the well-known trademarks used in different types of commodities, thus making the mark with the goods weakened ties between the specific acts the so-called defaced is that people will have no right to use the same Or similar marks for the well-known trade marks will have to belittle good reputation, tarnished the role of different types of goods on the act.Some scholars believe that the desalination also refers to the three aspects of well-known trademarks damage. First, in a certain way to demonize the relevant well-known trademarks; Second, some way related to well-known trademark dark; Third is the indirect way so that consumers will distort trade mark goods for the general misunderstanding of the name.In general, can be diluted in the form summarized as follows:1, weakeningWeakening is a typical diluted form, also known as dark, is that others will have some visibility in the use of a trademark is not the same, similar to the goods or services, thereby weakening the mark with its original logo of goods or services The link between, weakening the mark was a significant and identifiable, thus bearing the trade mark by the damage caused by acts of goodwill. Weakening the mark of recognition of the significant damage is serious, it can be the recognition of trademark dilution, was significant, or even make it completely disappeared, then to the mark bycarrying the reputation of devastating combat.First, the weakening of the identification is the weakening and lower. Any unauthorized person, others will have some visibility in the use of a trademark is not the same, similar to the goods or services, will reduce its recognition of. But consumers were referred to the mark, it may no longer think of first is the original goods or services, not only is the original or goods or services, consumers simply will not even think of goods or services, but the Trademark Dilution of goods Or services. There is no doubt that this marks the recognition of, is a heavy blow.Weakening of the mark is significantly weakened and the lower. Mark is significantly different from other commercial trademark marked characteristics. A certain well-known trademarks, which in itself should be a very significant, very significant and can be quickly and other signs of its own separate. However, the Trademark Dilution of the same or similar trademarks used in different goods or services, so that was the trademark and other commercial marked difference in greatly reduced, to the detriment of its significant.Of course, regardless of the weakening of the mark was a significant or identifiable, are the ultimate impact of the mark by the bearer of goodwill. Because the trade mark is the carrier of goodwill, the mark of any major damage, the final performance for all bearing the trade mark by the goodwill of the damage.2, tarnishedMeans others will have some well-known trademarks in the use of the good reputation of the trademark will have to belittle, defaced role of the goods or services on the act. Contaminate the trademarks of others, is a distortion of trade marks to others, the use of the damage, not only reduced the value of the mark, even on such values were defaced. As tarnished reputation is a trademark of damage, so tarnished included in the diluted acts, is also relatively accepted view. Moreover, in the field of trademark faded, tarnished than the weakening of the danger of even greater acts, the consequences are more serious.3, degradationDegradation is due to improper use of trademarks, trade mark goods for the evolution of the common name recognition and loss of function. Trademark Dilution degradation is the most serious kind. Degradation of the event, will completely lose their identification marks, no longer has the distinction function as the common name of the commodity.Fourth, protection against diluteBased on the well-known trademarks dilute the understanding, and accompanied by a serious weakening of well-known trademarks, all countries are gradually legislation to provide for the well-known trademarks to protect anti-diluted. There are specific models:1, the development of special anti-dilute the protection of well-known trademarksThe United States is taking this protection on behalf of the typical pattern.1995, in order to prevent lower dilute "the only representative of the public eye, the unique image of the trademark" to protect "the trademark value of advertising," the U.S. Congress passed the National reunification of the "anti-federal trademark law watered down", so as to the well-known trademarks All provide the unified and effective national anti-dilute the protection.U.S. anti-diluted in trademark protection has been added a new basis for litigation, which is different from the traditional basis of trademark infringement litigation. Trademark infringement of the criteria is confusing, the possibility of deception and misleading, and the Trademark Dilution criteria is unauthorized to others well-known trademarks of the public to reduce the use of the trademark instructions for goods and services only and in particular of Feelings. It is clear that the U.S. law is anti-diluted basis, "business reputation damage" and the possibility of well-known trade mark was a significant weakening of the possibility of providingrelief. Moreover, anti-faded law does not require the application of competitive relations or the existence of possible confusion, which is more conducive to the exercise of trademark right to appeal.2, through the Anti-Unfair Competition Law ProtectionSome countries apply anti-unfair competition law to protect famous trademarks from being watered down. Such as Greece, "Anti-Unfair Competition Law," the first one: "Prohibition of the Use of well-known trademarks in order to take advantage of different commodities on the well-known trademarks dilute its credibility was significant." Although some countries in the Anti-Unfair Competition Law does not explicitly prohibits trademark faded, but the Trademark Dilution proceedings, the application of unfair competition litigation.3, through or under well-known trademark protection within the scope of trademark protectionMost civil law countries is this way. 1991, "the French Intellectual Property Code," Di Qijuan trademark law section L.713-5 of the provisions that: not in similar goods or services on the use of well-known trade marks to the trademark owner or a loss caused by the improper use of trademarks , Against people should bear civil liability.Germany in 1995, "the protection of trademarks and other signs of" Article 14 also stipulates that: without the consent of the trademark rights of third parties should be banned in commercial activities, in and protected by the use of the trademark does not like similar goods or services , And the use of the trademark identical or similar to any signs.4, in the judicial precedents in the application of anti-dilute the protection ofIn some countries there are no clear legislative provisions of the anti-dilute well-known trademarks, but in judicial practice, they are generally applicable civil law on compensation for the infringement of the debt to protect the interests of allwell-known trademarks, through judicial precedents to dilute the protection of applicable anti.China's well-known trademarks in the protection of the law did not "water down" the reference, but on the substance of the relevant legal provisions, protection of anti-diluted. 2001 "Trademark Law" amendment to increase the protection of well-known trademarks, in particular, it is important to the well-known trademarks have been registered to conduct cross-category protection. Article 13 stipulates: "The meeting is not the same as or similar to the trademark application for registration of goods is copied, Mofang, translation others have been registered in the well-known trademarks, misleading the public, the standard of the well-known trade mark registration may be the interests of the damage, no registration And can not be used. "But needs to be pointed out that this provision does not mean that China's laws for the well-known trademarks has provided an effective anti-dilute the protection. "Trademark Law" will prohibit only well-known trademarks and trademarks of the same or similar use, without the same or similar goods not on the behavior, but the well-known trade marks have faded in various forms, such as the well-known trademarks for names, domain names, such acts Detract from the same well-known trademarks destroyed the logo of the ability to make well-known trade mark registration of the interests of damage, this is not a legal norms.It must be pointed out that the trade mark that should be paying attention to downplay acts of the following:1, downplay acts are specifically for the well-known registered trade marks.Perpetrators diluted one of the main purpose is the free-rider, using the credibility of well-known trademarks to sell their products, and general use of trademarks do not have this value. That acts to dilute limited to well-known trademarks, can effectively protect the rights of trademark rights, have not excessively restrict the freedom of choice of logo, is right to resolve the conflict right point of balance. "Trademark Law" will be divided into well-known trademarks have beenregistered and unregistered, and give different protection. Anti-has been watered down to protect only against the well-known trade marks registration, and for China not only well-known trade marks registered in the same or similar ban on the registration and use of goods. This reflects the "Trademark Law" the principle of protection of registered trademarks.2, faded in the different categories of goods and well-known trademarks for use on the same or similar logo.If this is the same or similar goods with well-known trademarks for use on the same or similar to the logo should be in accordance with the general treatment of trademark infringement. There is also a need to downplay the use of the tags are similar to a well-known trademarks and judgments.3, not all the non-use of similar products on the well-known trade marks and logos of the same or similar circumstances are all faded.When a trademark has not yet become well-known trademarks, perhaps there are some with the same or similar trademarks used in other types of goods on. In the well-known trademarks, the original has been in existence does not constitute a trademark of those who play down.4, acts that play down the perpetrator does not need to consider the subjective mental state.Regardless of their out of goodwill or malicious, intentional or fault, is not watered down the establishment. But the acts of subjective mental state will assume responsibility for its impact on the manner and scope. Generally speaking, if the perpetrator acts intentionally dilute the responsibility to shoulder much weight, in particular, bear a heavier responsibility for damages, if the fault is the commitment will be less responsibility. If there are no mistakes, just assume the responsibility to stop infringement.5, due to anti-faded to protect well-known trade marks with a specific goods orservices linked to well-known trademarks a long time widely used in a variety of goods, will inevitably lead to trademark the logo of a particular commodity producers play down the link, well-known trademarks A unique attraction to consumers will also be greatly reduced. So that should not be watered down to conduct a source of confusion for the conditions of goods, after all, not all the water down will cause consumers confusion. For example, a street shop's name is "Rolls-Royce fruit shop," people at this time there will be no confusion and that the shop and the famous Rolls-Royce trademark or producers of the contact. However, such acts can not be allowed, a large number of similar acts will dilute the Rolls-Royce trademark and its products linked to undermine the uniqueness of the trademark, if things continue this way when the mention of Rolls-Royce trademark, people may think of is not only Automobile, food, clothing, appliances, etc.. That faded as to cause confusion for the conditions, some will not dilute norms and suppression of acts, makes well-known trade marks are not well protected. Therefore, as long as it is a well-known trademark detract from the logo and unique ability to act on the behavior should be identified as diluted.1. Zheng Chengsi: "Intellectual property law", legal publishers 2003 version.2. Wu Handong editor: "Intellectual Property Law," China Politics and Law University Press 2002 edition.3. Susan. Sela De: "The United States Federal trademark law dilute the anti-legislation and practice," Zhang Jin Yi, contained in the "Law on Foreign Translation" 1998 No.4.4. Kong Xiangjun: "Anti-Unfair Competition AFP theory," People's Court Press, 2001 edition.5. Liu Ping, Qi Chang: "On the special protection of famous trademarks", in "law and commercial" 1998 No.6.6. Well-Tao, Lu Zhou Li: "On the well-known trademarks to protect the anti-diluted", in "Law" 1998 No. 5.2 外文参考文献原文浅谈驰名商标之淡化与反淡化一、驰名商标概述驰名商标是指经过长期使用，在市场上享有较高声誉，为相关公众所熟知，并经一定程序认定的商标。
常用研磨机外文文献翻译、中英文翻译、外文翻译
常用研磨机外文文献翻译、中英文翻译、外文翻译Grinding machine is a crucial n processing method that offers high machining accuracy and can process a wide range of materials。
It is suitable for almost all kinds of material processing。
and can achieve very high n and shape accuracy。
even reaching the limit。
The machining accuracy of grinding device is simple and does not require complex ___.2.Types of Grinding MachinesGrinding machines are mainly used for n grinding of workpiece planes。
cylindrical workpiece surfaces (both inside and outside)。
tapered faces inside。
spheres。
thread faces。
and other types of ___ grinding machines。
including disc-type grinding machines。
shaft-type grinding machines。
ic grinding machines。
and special grinding machines.3.Disc-type Grinding MachineThe disc-type grinding machine is a type of grinding machine that uses a grinding disc to grind the ___。
科技文献中英文对照翻译
Sensing Human Activity:GPS Tracking感应人类活动:GPS跟踪Stefan van der Spek1,*,Jeroen van Schaick1,Peter de Bois1,2and Remco de Haan1Abstract:The enhancement of GPS technology enables the use of GPS devices not only as navigation and orientation tools,but also as instruments used to capture travelled routes:assensors that measure activity on a city scale or the regional scale.TU Delft developed aprocess and database architecture for collecting data on pedestrian movement in threeEuropean city centres,Norwich,Rouen and Koblenz,and in another experiment forcollecting activity data of13families in Almere(The Netherlands)for one week.Thequestion posed in this paper is:what is the value of GPS as‘sensor technology’measuringactivities of people?The conclusion is that GPS offers a widely useable instrument tocollect invaluable spatial-temporal data on different scales and in different settings addingnew layers of knowledge to urban studies,but the use of GPS-technology and deploymentof GPS-devices still offers significant challenges for future research.摘要：增强GPS技术支持使用GPS设备不仅作为导航和定位工具,但也为仪器用来捕捉旅行路线:作为传感器,测量活动在一个城市或区域范围内规模。
智能交通系统中英文对照外文翻译文献
智能交通系统中英文对照外文翻译文献(文档含英文原文和中文翻译)原文:Traffic Assignment Forecast Model Research in ITS IntroductionThe intelligent transportation system (ITS) develops rapidly along with the city sustainable development, the digital city construction and the development of transportation. One of the main functions of the ITS is to improve transportation environment and alleviate the transportation jam, the most effective method to gain the aim is to forecast the traffic volume of the local network and the important nodes exactly with GIS function of path analysis and correlation mathematic methods, and this will lead a better planning of the traffic network. Traffic assignment forecast is an important phase of traffic volume forecast. It will assign the forecasted traffic to every way in the traffic sector. If the traffic volume of certain road is too big, which would bring on traffic jam, planners must consider the adoption of new roads or improving existing roads to alleviate the traffic congestion situation. This study attempts to present an improved traffic assignment forecast model, MPCC, based on analyzing the advantages and disadvantages of classic traffic assignment forecast models, and test the validity of the improved model in practice.1 Analysis of classic models1.1 Shortcut traffic assignmentShortcut traffic assignment is a static traffic assignment method. In this method, the traffic load impact in the vehicles’ travel is not considered, and the traffic impedance (travel time) is a constant. The traffic volume of every origination-destination couple will be assigned to the shortcut between the origination and destination, while the traffic volume of other roads in this sector is null. This assignment method has the advantage of simple calculation; however, uneven distribution of the traffic volume is its obvious shortcoming. Using this assignment method, the assignment traffic volume will be concentrated on the shortcut, which isobviously not realistic. However, shortcut traffic assignment is the basis of all theother traffic assignment methods.1.2 Multi-ways probability assignmentIn reality, travelers always want to choose the shortcut to the destination, whichis called the shortcut factor; however, as the complexity of the traffic network, thepath chosen may not necessarily be the shortcut, which is called the random factor.Although every traveler hopes to follow the shortcut, there are some whose choice isnot the shortcut in fact. The shorter the path is, the greater the probability of beingchosen is; the longer the path is, the smaller the probability of being chosen is.Therefore, the multi-ways probability assignment model is guided by the LOGIT model:∑---=n j ii i F F p 1)exp()exp(θθ (1)Where i p is the probability of the path section i; i F is the travel time of thepath section i; θ is the transport decision parameter, which is calculated by the followprinciple: firstly, calculate the i p with different θ (from 0 to 1), then find the θwhich makes i p the most proximate to the actual i p .The shortcut factor and the random factor is considered in multi-ways probabilityassignment, therefore, the assignment result is more reasonable, but the relationshipbetween traffic impedance and traffic load and road capacity is not considered in thismethod, which leads to the assignment result is imprecise in more crowded trafficnetwork. We attempt to improve the accuracy through integrating the several elements above in one model-MPCC.2 Multi-ways probability and capacity constraint model2.1 Rational path aggregateIn order to make the improved model more reasonable in the application, theconcept of rational path aggregate has been proposed. The rational path aggregate,which is the foundation of MPCC model, constrains the calculation scope. Rationalpath aggregate refers to the aggregate of paths between starts and ends of the trafficsector, defined by inner nodes ascertained by the following rules: the distancebetween the next inner node and the start can not be shorter than the distance betweenthe current one and the start; at the same time, the distance between the next innernode and the end can not be longer than the distance between the current one and theend. The multi-ways probability assignment model will be only used in the rationalpath aggregate to assign the forecast traffic volume, and this will greatly enhance theapplicability of this model.2.2 Model assumption1) Traffic impedance is not a constant. It is decided by the vehicle characteristicand the current traffic situation.2) The traffic impedance which travelers estimate is random and imprecise.3) Every traveler chooses the path from respective rational path aggregate.Based on the assumptions above, we can use the MPCC model to assign thetraffic volume in the sector of origination-destination couples.2.3 Calculation of path traffic impedanceActually, travelers have different understanding to path traffic impedance, butgenerally, the travel cost, which is mainly made up of forecast travel time, travellength and forecast travel outlay, is considered the traffic impedance. Eq. (2) displaysthis relationship. a a a a F L T C γβα++= (2)Where a C is the traffic impedance of the path section a; a T is the forecast traveltime of the path section a; a L is the travel length of the path section a; a F is theforecast travel outlay of the path section a; α, β, γ are the weight value of that threeelements which impact the traffic impedance. For a certain path section, there aredifferent α, β and γ value for different vehicles. We can get the weighted average of α,β and γ of each path section from the statistic percent of each type of vehicle in thepath section.2.4 Chosen probability in MPCCActually, travelers always want to follow the best path (broad sense shortcut), butbecause of the impact of random factor, travelers just can choose the path which is ofthe smallest traffic impedance they estimate by themselves. It is the key point ofMPCC. According to the random utility theory of economics, if traffic impedance is considered as the negativeutility, the chosen probability rs p of origination-destinationpoints couple (r, s) should follow LOGIT model:∑---=n j jrs rs bC bC p 1)exp()exp( (3) where rs p is the chosen probability of the pathsection (r, s);rs C is the traffic impedance of the path sect-ion (r, s); j C is the trafficimpedance of each path section in the forecast traffic sector; b reflects the travelers’cognition to the traffic impedance of paths in the traffic sector, which has reverseratio to its deviation. If b → ∞ , the deviation of understanding extent of trafficimpedance approaches to 0. In this case, all the travelers will follow the path whichis of the smallest traffic impedance, which equals to the assignment results withShortcut Traffic Assignment. Contrarily, if b → 0, travelers ’ understanding error approaches infinity. In this case, the paths travelers choose are scattered. There is anobjection that b is of dimension in Eq.(3). Because the deviation of b should beknown before, it is difficult to determine the value of b. Therefore, Eq.(3) is improvedas follows:∑---=n j OD j OD rsrs C bC C bC p 1)exp()exp(，∑-=n j j OD C n C 11（4） Where OD C is the average of the traffic impedance of all the as-signed paths; bwhich is of no dimension, just has relationship to the rational path aggregate, ratherthan the traffic impedance. According to actual observation, the range of b which is anexperience value is generally between 3.00 to 4.00. For the more crowded cityinternal roads, b is normally between 3.00 and 3.50.2.5 Flow of MPCCMPCC model combines the idea of multi-ways probability assignment anditerative capacity constraint traffic assignment.Firstly, we can get the geometric information of the road network and OD trafficvolume from related data. Then we determine the rational path aggregate with themethod which is explained in Section 2.1.Secondly, we can calculate the traffic impedance of each path section with Eq.(2),Fig.1 Flowchart of MPCC which is expatiated in Section 2.3.Thirdly, on the foundation of the traffic impedance of each path section, we cancalculate the respective forecast traffic volume of every path section with improvedLOGIT model (Eq.(4)) in Section 2.4, which is the key point of MPCC.Fourthly, through the calculation processabove, we can get the chosen probability andforecast traffic volume of each path section, but itis not the end. We must recalculate the trafficimpedance again in the new traffic volumesituation. As is shown in Fig.1, because of theconsideration of the relationship between trafficimpedance and traffic load, the traffic impedanceand forecast assignment traffic volume of everypath will be continually amended. Using therelationship model between average speed andtraffic volume, we can calculate the travel timeand the traffic impedance of certain path sect-ionunder different traffic volume situation. For theroads with different technical levels, therelationship models between average speeds totraffic volume are as follows: 1) Highway: 1082.049.179AN V = (5) 2) Level 1 Roads: 11433.084.155AN V = (6) 3) Level 2 Roads: 66.091.057.112AN V = (7) 4) Level 3 Roads: 3.132.01.99AN V = (8) 5) Level 4 Roads: 0988.05.70A N V =(9) Where V is the average speed of the path section; A N is the traffic volume of thepath section.At the end, we can repeat assigning traffic volume of path sections with themethod in previous step, which is the idea of iterative capacity constraint assignment,until the traffic volume of every path section is stable.译文智能交通交通量分配预测模型介绍随着城市的可持续化发展、数字化城市的建设以及交通运输业的发展，智能交通系统（ITS）的发展越来越快。
建筑三维模型分析中英文资料对照外文翻译文献
建筑三维模型分析中英文资料对照外文翻译文献本文档对比了建筑三维模型分析方面的中英文资料，并提供了相应的外文翻译文献。
以下是对比内容：1. 中文资料：中文资料：建筑三维模型分析是基于三维建模技术，通过对建筑模型进行分析和评估，以帮助设计师评估和改进设计方案的可行性和性能。
这些模型可以用于预测建筑物的能源效率、结构强度、照明效果等方面的性能。
2. 英文资料：英文资料：- 文献1:标题："A Review of Three-Dimensional Model Analysis in Architecture"作者：John Smith来源：International Journal of Architectural Analysis摘要：本文综述了建筑领域中三维模型分析的研究进展。
通过分析现有文献，总结了三维模型分析在建筑设计中的应用、方法和技术。
文章还讨论了目前存在的挑战和未来的研究方向。
- 文献2:标题："Performance Analysis of Building Models Using Three-Dimensional Simulation"作者：Jane Doe来源：Journal of Building Performance摘要：本文介绍了利用三维模拟技术对建筑模型进行性能分析的方法。
通过模拟建筑物在不同环境条件下的行为，提供了对建筑物能源效率、照明效果和空气流动等方面性能的评估。
文章还讨论了如何利用这些分析结果来优化建筑设计。
3. 外文翻译文献：外文翻译文献：- 文献1：《建筑中三维模型分析的综述》- 翻译摘要：本文综述了建筑领域中三维模型分析的研究进展。
通过分析现有文献，总结了三维模型分析在建筑设计中的应用、方法和技术。
文章还讨论了目前存在的挑战和未来的研究方向。
翻译摘要：本文综述了建筑领域中三维模型分析的研究进展。
通过分析现有文献，总结了三维模型分析在建筑设计中的应用、方法和技术。
工程管理专业外文文献翻译(中英文)【精选文档】
xxxxxx 大学本科毕业设计外文翻译Project Cost Control: the Way it Works项目成本控制：它的工作方式学院（系）: xxxxxxxxxxxx专业: xxxxxxxx学生姓名: xxxxx学号： xxxxxxxxxx指导教师： xxxxxx评阅教师：完成日期：xxxx大学项目成本控制：它的工作方式在最近的一次咨询任务中，我们意识到对于整个项目成本控制体系是如何设置和应用的,仍有一些缺乏理解。
所以我们决定描述它是如何工作的.理论上，项目成本控制不是很难跟随。
首先，建立一组参考基线。
然后，随着工作的深入，监控工作,分析研究结果,预测最终结果并比较参考基准。
如果最终的结果不令人满意，那么你要对正在进行的工作进行必要的调整，并在合适的时间间隔重复。
如果最终的结果确实不符合基线计划，你可能不得不改变计划.更有可能的是，会 (或已经) 有范围变更来改变参考基线，这意味着每次出现这种情况你必须改变基线计划。
但在实践中，项目成本控制要困难得多，通过项目数量无法控制成本也证明了这一点。
正如我们将看到的，它还需要大量的工作，我们不妨从一开始启用它。
所以，要跟随项目成本控制在整个项目的生命周期.同时，我们会利用这一机会来指出几个重要文件的适当的地方。
其中包括商业案例，请求（资本)拨款（执行），工作包和工作分解结构，项目章程（或摘要),项目预算或成本计划、挣值和成本基线。
所有这些有助于提高这个组织的有效地控制项目成本的能力。
业务用例和应用程序（执行）的资金重要的是要注意，当负责的管理者对于项目应如何通过项目生命周期展开有很好的理解时,项目成本控制才是最有效的。
这意味着他们在主要阶段的关键决策点之间行使职责。
他们还必须识别项目风险管理的重要性，至少可以确定并计划阻止最明显的潜在风险事件。
在项目的概念阶段•每个项目始于确定的机会或需要的人.通常是有着重要性和影响力的人,如果项目继续,这个人往往成为项目的赞助。
中英文文献翻译pid控制器--大学毕业设计论文
附件1：外文原文PID controllerZuo Xin and Sun Jinming(Research Institute ofAutomation, University of Petroleum,Belting 102249,China)Received April 2，2005Abstract:Performance assessment of a proportional-integral-derivative(PID)controller is condueted using the PID achievable minimum variance as abenchmark．When the process model is unknown，we carl estimate the P／D·achievable minimum variance and the corresponding parameters by routine closed-loop operation data．Simulation results show that the process output variance is reduced by retuning controller parameters．Key words：Performance assessment，PID control，minimum varianceA proportional–integral–derivative controller (PID controller) is a generic .control loop feedback mechanism widely used in industrial control systems.A PID controller attempts to correct the error between a measured process variable and a desired setpoint by calculating and then outputting a corrective action that can adjust the process accordingly.The PID controller calculation (algorithm) involves three separate parameters; the Proportional, the Integral and Derivative values. The Proportional value determines the reaction to the current error, the Integral determines the reaction based on the sum of recent errors and the Derivative determines the reaction to the rate at which the error has been changing. The weightedsum of these three actions is used to adjust the process via a control element such as the position of a control valve or the power supply of a heating element.By "tuning" the three constants in the PID controller algorithm the PID can provide control action designed for specific process requirements. The response of the controller can be described in terms of the responsiveness of the controller to an error, the degree to which the controller overshoots the setpoint and the degree of system oscillation. Note that the use of the PID algorithm for control does not guarantee optimal control of the system or systemstability.Some applications may require using only one or two modes to provide the appropriate system control. This is achieved by setting the gain of undesired control outputs to zero. A PID controller will be called a PI, PD, P or I controller in the absence of the respective control actions. PI controllers are particularly common, since derivative action is very sensitive to measurement noise, and the absence of an integral value may prevent the system from reaching its target value due to the control action.Note: Due to the diversity of the field of control theory and application, many naming conventions for the relevant variables are in common use.1.Control loop basicsA familiar example of a control loop is the action taken to keep one's shower water at the ideal temperature, which typically involves the mixing of two process streams, cold and hot water. The person feels the water to estimate its temperature. Based on this measurement they perform a control action: use the cold water tap to adjust the process. The person would repeat this input-output control loop, adjusting the hot water flow until the process temperature stabilized at the desired value.Feeling the water temperature is taking a measurement of the process value or process variable (PV). The desired temperature is called the setpoint (SP). The output from the controller and input to the process (the tap position) is called the manipulated variable (MV). The difference between the measurement and the setpoint is the error (e), too hot or too cold and by how much.As a controller, one decides roughly how much to change the tap position (MV) after one determines the temperature (PV), and therefore the error. This first estimate is the equivalent of the proportional action of a PID controller. The integral action of a PID controller can be thought of as gradually adjusting the temperature when it is almost right. Derivative action can be thought of as noticing the water temperature is getting hotter or colder, and how fast, and taking that into account when deciding how to adjust the tap.Making a change that is too large when the error is small is equivalent to a high gain controller and will lead toovershoot. If the controller were to repeatedly make changes that were too large and repeatedly overshoot the target, this control loop would be termed unstable and the output would oscillate around the setpoint in either a constant, growing, or decaying sinusoid. A human would not do this because we are adaptive controllers, learning from the process history, but PID controllers do not have the ability to learn and must be set up correctly. Selecting the correct gains for effective control is known as tuning the controller.If a controller starts from a stable state at zero error (PV = SP), then further changes by the controller will be in response to changes in other measured or unmeasured inputs to the process that impact on the process, and hence on the PV. Variables that impact on the process other than the MV are known as disturbances and generally controllers are used to reject disturbances and/or implement setpoint changes. Changes in feed water temperature constitute a disturbance to the shower process.In theory, a controller can be used to control any process which has a measurable output (PV), a known ideal value for that output (SP) and an input to the process (MV) that will affect the relevant PV. Controllers are used in industry to regulate temperature, pressure, flow rate, chemical composition, speed and practically every other variable for which a measurement exists. Automobile cruise control is an example of a process which utilizes automated control.Due to their long history, simplicity, well grounded theory and simple setup and maintenance requirements, PID controllers are the controllers of choice for many of these applications.2.PID controller theoryNote: This section describes the ideal parallel or non-interacting form of the PID controller. For other forms please see the Section "Alternative notation and PID forms".The PID control scheme is named after its three correcting terms, whose sum constitutes the manipulated variable (MV). Hence:Where Pout, Iout, and Dout are the contributions to the output from the PID controller from each of the three terms, as defined below.2.1. Proportional termThe proportional term makes a change to the output that is proportional to the current error value. The proportional response can be adjusted by multiplying the error by a constant Kp, called the proportional gain.The proportional term is given by:WherePout: Proportional outputKp: Proportional Gain, a tuning parametere: Error = SP − PVt: Time or instantaneous time (the present)Change of response for varying KpA high proportional gain results in a large change in the output for a given change in the error. If the proportional gain is too high, the system can become unstable (See the section on Loop Tuning). In contrast, a small gain results in a small output response to a large input error, and a less responsive (or sensitive) controller. If the proportional gain is too low, the control action may be too small when responding to system disturbances.In the absence of disturbances, pure proportional control will not settle at its target value, but will retain a steady state error that is a function of the proportional gain and the process gain. Despite the steady-state offset, both tuning theory and industrial practice indicate that it is the proportional term that should contribute the bulk of the output change.2.2.Integral termThe contribution from the integral term is proportional to both the magnitude of the error and the duration of the error. Summing the instantaneous error over time (integrating the error) gives the accumulated offset that should have been correctedpreviously. The accumulated error is then multiplied by the integral gain and added to the controller output. The magnitude of the contribution of the integral term to the overall control action is determined by the integral gain, Ki.The integral term is given by:Iout: Integral outputKi: Integral Gain, a tuning parametere: Error = SP − PVτ: Time in the past contributing to the integral responseThe integral term (when added to the proportional term) accelerates the movement of the process towards setpoint and eliminates the residual steady-state error that occurs with a proportional only controller. However, since the integral term is responding to accumulated errors from the past, it can cause the present value to overshoot the setpoint value (cross over the setpoint and then create a deviation in the other direction). For further notes regarding integral gain tuning and controller stability, see the section on loop tuning.2.3 Derivative termThe rate of change of the process error is calculated by determining the slope of the error over time (i.e. its first derivative with respect to time) and multiplying this rate of change by the derivative gain Kd. The magnitude of the contribution of the derivative term to the overall control action is termed the derivative gain, Kd.The derivative term is given by:Dout: Derivative outputKd: Derivative Gain, a tuning parametere: Error = SP − PVt: Time or instantaneous time (the present)The derivative term slows the rate of change of the controller output and this effect is most noticeable close to the controller setpoint. Hence, derivative control is used to reduce the magnitude of the overshoot produced by the integral component and improve the combined controller-process stability. However, differentiation of a signal amplifies noise and thus this term in the controller is highly sensitive to noise in the error term, and can cause a process to become unstable if the noise and the derivative gain are sufficiently large.2.4 SummaryThe output from the three terms, the proportional, the integral and the derivative terms are summed to calculate the output of the PID controller. Defining u(t) as the controller output, the final form of the PID algorithm is:and the tuning parameters areKp: Proportional Gain - Larger Kp typically means faster response since thelarger the error, the larger the Proportional term compensation. An excessively large proportional gain will lead to process instability and oscillation.Ki: Integral Gain - Larger Ki implies steady state errors are eliminated quicker. The trade-off is larger overshoot: any negative error integrated during transient response must be integrated away by positive error before we reach steady state.Kd: Derivative Gain - Larger Kd decreases overshoot, but slows down transient response and may lead to instability due to signal noise amplification in the differentiation of the error.3. Loop tuningIf the PID controller parameters (the gains of the proportional, integral and derivative terms) are chosen incorrectly, the controlled process input can be unstable, i.e. its output diverges, with or without oscillation, and is limited only by saturation or mechanical breakage. Tuning a control loop is the adjustment of its control parameters (gain/proportional band, integral gain/reset, derivative gain/rate) to the optimumvalues for the desired control response.The optimum behavior on a process change or setpoint change varies depending on the application. Some processes must not allow an overshoot of the process variable beyond the setpoint if, for example, this would be unsafe. Other processes must minimize the energy expended in reaching a new setpoint. Generally, stability of response (the reverse of instability) is required and the process must not oscillate for any combination of process conditions and setpoints. Some processes have a degree of non-linearity and so parameters that work well at full-load conditions don't work when the process is starting up from no-load. This section describes some traditional manual methods for loop tuning.There are several methods for tuning a PID loop. The most effective methods generally involve the development of some form of process model, then choosing P, I, and D based on the dynamic model parameters. Manual tuning methods can be relatively inefficient.The choice of method will depend largely on whether or not the loop can be taken "offline" for tuning, and the response time of the system. If the system can be taken offline, the best tuning method often involves subjecting the system to a step change in input, measuring the output as a function of time, and using this response to determine the control parameters.Choosing a Tuning MethodMethodAdvantagesDisadvantagesManual TuningNo math required. Online method.Requires experiencedpersonnel.Ziegler–NicholsProven Method. Online method.Process upset, sometrial-and-error, very aggressive tuning.Software ToolsConsistent tuning. Online or offline method. May includevalve and sensor analysis. Allow simulation before downloading.Some cost and training involved.Cohen-CoonGood process models.Some math. Offline method. Onlygood for first-order processes.3.1 Manual tuningIf the system must remain online, one tuning method is to first set the I and D values to zero. Increase the P until the output of the loop oscillates, then the P should be left set to be approximately half of that value for a "quarter amplitude decay" type response. Then increase D until any offset is correct in sufficient time for the process. However, too much D will cause instability. Finally, increase I, if required, until the loop is acceptably quick to reach its reference after a load disturbance. However, too much I will cause excessive response and overshoot. A fast PID loop tuning usually overshoots slightly to reach the setpoint more quickly; however, some systems cannot accept overshoot, in which case an "over-damped" closed-loop system is required, which will require a P setting significantly less than half that of the P setting causing oscillation.3.2Ziegler–Nichols methodAnother tuning method is formally known as the Ziegler–Nichols method, introduced by John G. Ziegler and Nathaniel B. Nichols. As in the method above, the I and D gains are first set to zero. The "P" gain is increased until it reaches the "critical gain" Kc at which the output of the loop starts to oscillate. Kc and the oscillation period Pc are used to set the gains as shown:3.3 PID tuning softwareMost modern industrial facilities no longer tune loops using the manual calculation methods shown above. Instead, PID tuning and loop optimization software are used to ensure consistent results. These software packages will gather the data, develop process models, and suggest optimal tuning. Some software packages can even develop tuning by gathering data from reference changes.Mathematical PID loop tuning induces an impulse in the system, and then uses the controlled system's frequency response to design the PID loop values. In loops with response times of several minutes, mathematical loop tuning is recommended, because trial and error can literally take days just to find a stable set of loop values.Optimal values are harder to find. Some digital loop controllers offer a self-tuning feature in which very small setpoint changes are sent to the process, allowing the controller itself to calculate optimal tuning values.Other formulas are available to tune the loop according to different performance criteria.4 Modifications to the PID algorithmThe basic PID algorithm presents some challenges in control applications that have been addressed by minor modifications to the PID form.One common problem resulting from the ideal PID implementations is integralwindup. This can be addressed by:Initializing the controller integral to a desired valueDisabling the integral function until the PV has entered the controllable region Limiting the time period over which the integral error is calculatedPreventing the integral term from accumulating above or below pre-determined boundsMany PID loops control a mechanical device (for example, a valve). Mechanical maintenance can be a major cost and wear leads to control degradation in the form of either stiction or a deadband in the mechanical response to an input signal. The rate of mechanical wear is mainly a function of how often a device is activated to make a change. Where wear is a significant concern, the PID loop may have an output deadband to reduce the frequency of activation of the output (valve). This is accomplished by modifying the controller to hold its output steady if the change would be small (within the defined deadband range). The calculated output must leave the deadband before the actual output will change.The proportional and derivative terms can produce excessive movement in the output when a system is subjected to an instantaneous "step" increase in the error, such as a large setpoint change. In the case of the derivative term, this is due to taking the derivative of the error, which is very large in the case of an instantaneous step change.5. Limitations of PID controlWhile PID controllers are applicable to many control problems, they can perform poorly in some applications.PID controllers, when used alone, can give poor performance when the PID loop gains must be reduced so that the control system does not overshoot, oscillate or "hunt" about the control setpoint value. The control system performance can be improved by combining the feedback (or closed-loop) control of a PID controller with feed-forward (or open-loop) control. Knowledge about the system (such as the desired acceleration and inertia) can be "fed forward" and combined with the PID output to improve the overall system performance. The feed-forward value alone can often provide the major portion of the controller output. The PID controller can then be used primarily to respond to whatever difference or "error" remains between the setpoint (SP) and the actual value of the process variable (PV). Since the feed-forward output is not affected by the process feedback, it can never cause the control system to oscillate, thus improving the system response and stability.For example, in most motion control systems, in order to accelerate a mechanical load under control, more force or torque is required from the prime mover, motor, or actuator. If a velocity loop PID controller is being used to control the speed of the load and command the force or torque being applied by the prime mover, then it is beneficial to take the instantaneous acceleration desired for the load, scale that value appropriately and add it to the output of the PID velocity loop controller. This means that whenever the load is being accelerated or decelerated, a proportional amount of force is commanded from the prime mover regardless of the feedback value. The PID loop in this situation uses the feedback information to effect any increase or decrease of the combined output in order to reduce the remaining difference between the process setpoint and thefeedback value. Working together, the combined open-loop feed-forward controller and closed-loop PID controller can provide a more responsive, stable and reliable control system.Another problem faced with PID controllers is that they are linear. Thus, performance of PID controllers in non-linear systems (such as HV AC systems) isvariable. Often PID controllers are enhanced through methods such as PID gain scheduling or fuzzy logic. Further practical application issues can arise from instrumentation connected to the controller. A high enough sampling rate, measurement precision, and measurement accuracy are required to achieve adequate control performance.A problem with the Derivative term is that small amounts of measurement or process noise can cause large amounts of change in the output. It is often helpful to filter the measurements with a low-pass filter in order to remove higher-frequency noise components. However, low-pass filtering and derivative control can cancel each other out, so reducing noise by instrumentation means is a much better choice. Alternatively, the differential band can be turned off in many systems with little loss of control. This is equivalent to using the PID controller as a PI controller.6. Cascade controlOne distinctive advantage of PID controllers is that two PID controllers can be used together to yield better dynamic performance. This is called cascaded PID control. In cascade control there are two PIDs arranged with one PID controlling the set point of another. A PID controller acts as outer loop controller, which controls the primary physical parameter, such as fluid level or velocity. The other controller acts as inner loop controller, which reads the output of outer loop controller as set point, usually controlling a more rapid changing parameter, flowrate or accelleration. It can be mathematically proved that the working frequency of the controller is increased and the time constant of the object is reduced by using cascaded PID controller.[vague]7. Physical implementation of PID controlIn the early history of automatic process control the PID controller was implemented as a mechanical device. These mechanical controllers used a lever, spring and a mass and were often energized by compressed air. These pneumatic controllers were once the industry standard.Electronic analog controllers can be made from a solid-state or tube amplifier, a capacitor and a resistance. Electronic analogPID control loops were often found within more complex electronic systems, for example, the head positioning of a disk drive, the power conditioning of a power supply, or even the movement-detection circuit of a modern seismometer. Nowadays, electronic controllers have largely been replaced by digital controllers implemented with microcontrollers or FPGAs.Most modern PID controllers in industry are implemented in software in programmable logic controllers (PLCs) or as a panel-mounted digital controller. Software implementations have the advantages that they are relatively cheap and are flexible with respect to the implementation of the PID algorithm.References[1]Byung，S.K.(2000)On Performance Assessment of Feedback Control Loops．Austin：The University of Texas Austin[2]Desborough，L．and Harris，T.(1992)Performance Assessment Measures for Univariate Feedback Control. The Canadian Journal of Chemical Engineering,70(12)．1186-1197[3]Ender,D.B.(1993)Process Control Performance：Not as Good as You Think．Control Engineering，40(10)[4]Harris,T(1993)Pefformance Assessment Measllres for Univariate Feedforward/Feedback Control．The Canadian Journal of Chemical Engineering，71(8)，1186-1197[5]Qin，S．J．(1 998)Contr01 Performance Monitoring： A Review and Assessment．Com．Chem．Eng．，(23)，173．186[6]Sun,Jinming(2004)PID Performance Assessment and Parameters Tuning．Beijing：China University of Petroleum[7]Xu，Xi；Li，Tao and Bo，Xiaochen(2000)Matlab Toolbox Application--Control Engineering．Bering：Electron Industry Press附件2：外文资料翻译译文PID控制器左信孙金明（石油大学自动化研究所，北京，102249，中国）发表于2005.4.2摘要：一个比例积分微分（PID）控制器的性能评价进行使用PID实现的最小方差作为参照。
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英文原文Case StudyTheoretical and practical aspects of the wear of vane pumpsPart A. Adaptation of a model for predictive wear calculationAbstractThe aim of this investigation is the development of a mathematical tool for predicting the wear behaviour of vane pumps uscd in the standard method for indicating the wcar charactcristics of hydraulic fluids according to ASTM D 2882/DIN 51389.The derivation of the corresponding mathematical algorithm is based on the description of the combined abrasive andadhesive wear phenomena occurring on the ring and vanes of the pump by the shear energy hypothesis, in connection withstochastic modelling of the contacting rough surfaces as two-dimensional isotropic random fields. Starting from a comprehensive analysis of the decisive ring-vane tribo contact, which supplies essential input data for the wear calculation, the computational method is adapted to the concrete geometrical, motional and loading conditions of thetribo system vane pump and extended by inclusion of partial elastohydrodynamic lubrication in the mathematical modej.For comparison of the calculated wear behaviour with expenmental results, a test series on a rig described in Part B was carried out. A mineral oil-based lubricant without any additives was used to exclude the influence of additives which cannot be described in the mathematical model. A good qualitative correspondence between calculation and experiment regarding the temporal wear progress and the amount of calculated wear mass was achieved.Keywords: Mathematical modelling; Simulation of wear mechanisms; Wear testing devices; Hydraulic vane pumps; Elastohydrodynamic lubrication;Surface roughness1. IntroductionIn this study, the preliminary results of a newmethodological approach to the development of tribo- meters for complicated tribo sysLems are presented. The basic concept involves the derivation of a mathematical algofithm for wear calculation in an interactive process with experiments, which can be used model of the tribo system to be simulated. In this way, an additional design tool to achieve the correlation of the wear rates of the model and original system is created.The investigations are performed for the Vickers vane pump V104 C usedin the standard method forindicating the wear characteristics of hydraulic fluids according to ASTM D 2882/DIN 51 389. In a first step, a mathematical theory based on the description of abrasive and adhesive wear phenomena by the shear energy hypothesis, and including stochastic modelling of the contacting rough surfaces, is adapted to the tribological reality of the vane pump, extended byaspects of partial elastohydrodynamic lubrication and verified by corresponding experiments.Part A of this study is devoted to the mathematical modelling of the wear behaviour of the vane pump and to the verification of the resulting algorithm; experimental wear investigations represent the focal point of Part B, and these are compared with the results of the computational method derived in Part A.2. Analysis of the tribo contactThe Vickers vane pump V 104 C is constructed as a pump for constant volume flow per revolution. The system pressure is led to the bottom side of the 12 vanes in the rotor slots to seal the cells formed by each pair of vanes, the ring, the rotor and the bushings in the tribologically interesting line contact of the vane and inner curvature of the ring (Fig. 1). Simultaneously, all other vane sides are stressed with different and periodically alternating pressures of the fiuid. A comprehensive structure and stress analysis based on quasistatic modelling of all inertial forces acting on the pump, and considering the inner curvature of the ring, the swivel motion of the vanes in relation to the tangent of curvature and the loading assumptions, is described in Refs. [1-3]. Thereby, a characteristic graph for the contact force Fe as a function of the turn angle can be obtained, which depends on the geometry of the vanes used in each run and the system pressure. From this, the inner curvature of the ring can be divided into four zones of different loading conditions in vane-ring tribo contact (Fig. 2), which is in good agreement with the wear measurements on the rings: in the area of maximum contact force (zone n), the highest linear wear could be found [2,3] (see also PartB).3. Mathematical modelling3.1. Basic relations for wear calculationThe vane and ring show combined abrasive and adhesive wear phenomena (Fig. 3). The basic concepts of the theory for the predictive calculation of such wear phenomena are described in Refs. [4-6].Starting from the assumption that wear is caused by shear effects in the surface regions of contacting bodies in relative motion, the fundamental equation(1)for the linear wear intensity Ih in the stationary wear state can be derived, which contains the specific shear energy density es/ro, interpretable as a material constant, and the real areaArs of the asperity contacts undergoing shear. To determine this real contact area, the de- scription of the contacting rough surfaces as two-dimensional isotropic gaussian fields according to Ref.[7] is included in the modelling. Thus the implicit functional relationwith the weight function(2)is found, which can be used to calculate the surface ratio in Eq. (1) for unlubricated contacts from the hertzian pressure Pa acting in the investigated tribo contact by a complicated iterative process described in Refs. [6,8]. The concrete structure of the functions Fand c depends on the relative motion of the contacting bodies (sliding, rolling). The parameter a- （m0m4）/m22represents the properties of the rough surface by its spectral moments, which can be deter- mined statistically from surface profilometry, and the plasticity index妒= (mOm4)y4(E'/H) is a measure of the ratio of elastic and plastic microcontacts.3.2. Extension to lubricated contactsThe algorithm resulting from the basic relations for wear calculation was applied successfully to unlubricated tribo systems [8]. The first concepts for involving lubrication in the mathematical model are developed in Ref. [8]. They are based on the application of the classical theory of elastohydrodynamic lubrication (EHL) to the microcontacts of the asperities, neglecting the fact that there is also a "macrolubrication film" which separates the contacting bodies and is interrupted in the case of partial lubrication by the asperity microcontacts. Therefore their use for calculating practical wear problems leads to unsatisfactory results [9]. They are extended here by including the following assump- tions in the mathematical model.(1) Lubrication causes the separation of contacting bodies by a macrofilm with a mean thickness u. which can be expressed in terms of the surfaceroughness by [10](3)Where u0 is the mean film thinkness according to classical EHL theory between two ideally smooth bodies, which can be determined for line contact of the vane and ring by[11](2) In the case of partial lubrication, the macrofilm is interrupted during asperity contacts. A plastic microcontact is interpreted as a pure solid state contact, whereas for an elastic contact theroughness is superimposed by a microlubrication film. Because of the modelling of the asperities as spherical indenters, the microfilm thickness can be determined using the EHL theory for sphere-plane contacts, which is represented in the random model by the sliding number [8](5)(3) The hertzian pressure acting in the macrocontact works in two parts: as a hydrodynamic pressure pEH borne by the macrolubrication film and as a pressure pFK borne by the roughness in solid body contact.(4) For pure solid state contacts, it is assumed that the limit for the mean real pressure prFK which an asperity can resist without plastic deformation can be estimated by one-fifth to one-sixth of its hardness(6)Investigations on the contact stiffness in Ref. [11] have led to the conclusion that the elastic properties of the lubrication film cause a relief of the asperities, which means that the real pressure working on the asperity is damped. Therefore, in the mathematical model for lubricated tribo systems, an additional term fffin, which corrects the upper limit of the real pressure as a function of the film thickness, is introduced p,EH =prFK[1 -fcorr(U)] (7)This formula can be used to determine a modified plasticity index {PEH for lubricated contacts according to Ref. [8].Altogether, the basic model for wear calculation can be extended for lubricated tribo systems by replacing relation (2) by(8)(3)3.3. Adaptation to the tribo’system vane pumpTo apply the mathematical model for wear calculation to a concrete tribo system, all material data (specific material and fluid properties, roughness parameters) used by the algorithm must be determined (see Part B). Moreover, the model must be adapted to the mechanical conditions of the wear process investigated. On the one hand, this is related to the relative motion of the bodies in tribo contact, which influences the concrete structure of function f in formulae (2) and (8). In the case of vane-ring contact, sliding with superimposed rolling due to the swivel motion of the vanes was modelled(9)A detailed derivation of the corresponding formulae for fsliding and f.olling can be found in Refs.[8,9].On the other hand, the hertzian presstire Pa acting on tribo contact during the wear process has an esseritial importance in the wear calculation. For the tribo system vane pump, the mean contact force Fe in each loading zone can be regarded as constant, whereas the hertzianpressure decreases with time. The reason for this is the wear debris on the vane, which causes a change 'n the vane tip shape with time,leading to an increased contact radius and, accordingly, a larger contact areaTo describe this phenomenon by the mathematical wear model, the volume removal Wvl of one vane in terms of the respective contact radius Ri(t) at time t and the sliding distance SR(Rl(t》is given by(10)where the constants a and b can be determined by regression from the geometrical data of the tested vanes. The corresponding sliding distance necessary to reach a certain radius Ri due to vane wear can be expressed using the basic equation (1):(11)Thus, applying Eq. (11) together with Eq. (10) to the relation(12)it is possible to derive the following differential equation for the respective volume removal Wvll of the ring, which can be solved by a numerical procedure(13)The required wear intensities of the vane and ring can be calculated by Eq. (8) as a function of the contact radius from the hertzian pressures working in each loading zone, which are available from the contact force by the well-known hertzian formulae.3.4 Possibilities of verificationIf all input data are available for a concrete vane pump run (the concrete geometrical, material and mechanical conditions in the cartridge used and the specific fluid properties, see Part B), the mathematical model for the calculation of the wear of vane pumps derived above can describe quantitatively the following relations.(1) The sliding distance SR(RI) and, if the number of revolutions of the pump and the size of the inner ring surface are known, the respective run time t of the pump which is necessary to reach a certain shape of the vane tips due to wear.(2) The volume removal W,.:uri(t) and the wear masses WmW(t) of the vane and ring as a function of the run time t.(3) The mean local linear wear Wl(t) in every loading zone on the ring at time t.Thus an immediate comparison between the calculated and experimentally established wear behaviour, with regard to the wear progress in time, the local wear progress on the ring and the wear masses at a certain time t, becomes possible.4。