Extraction of the Generalized Parton Distribution H(xi,xi,t) from DVCS

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《你是我的不二闺蜜—女性朋友间的话语解读》（第六章）翻译实践报告

A Report on the Translation of You’re the Only One I Can Tell: Inside theLanguage of Women’s Friendships（Chapter 6）ByLi QiuyuA Thesis Submitted to the Graduate Schoolof Sichuan International Studies UniversityIn Partial Fulfillment of the Requirementsfor the Degree ofMaster of Translation and InterpretingUnder the Supervision of Associate Professor Xia XindongMay, 2018《你是我的不二闺蜜——女性朋友间的话语解读》（第六章）翻译实践报告摘要本翻译报告的原文选自《你是我的不二闺蜜——女性朋友间的话语解读》一书中第六章。

该书由美国语言学教授黛博拉·坦嫩所著，探讨了过分亲密给友谊带来的潜在伤害。

本报告分为四章：第一章是介绍翻译报告的背景、目标、和结构。

第二章是介绍源文文本相关内容，包括介绍作者、源文内容以及对源文特征的分析。

根据彼得·纽马克的文本类型理论，源文属于信息型文本，翻译该类文本时，应该确保译文的可读性。

第三章主要是对翻译指导理论的选择和应用，同时本章还提到翻译过程中的相应策略。

本翻译报告以彼得·纽马克的交际翻译为理论基础，并结合自身翻译实践，探讨了其在翻译过程中的指导作用。

第四章是对翻译报告的总结，包括翻译过程中积累的经验教训及遗留的个别问题。

关键词：翻译报告；信息型文本；交际翻译；翻译技巧A Report on the Translation of You’re the Only One I Can Tell:Inside the Language of Women’s Friendships（Chapter 6）AbstractThis is a report on the translation of Chapter 6 of You’re the Only One I Can Tell: Inside the Language of Women’s Friendships authored by Deborah Tannen, an American academic professor. The book is about general information of intimacy and its potential harm to friendships. This translation report is mainly classified into four chapters: Chapter 1 gives a brief introduction to project background, objectives and structure of the translation report. Chapter 2 consists of the author’s basic information, publishing facts and main ideas of the original text. Based on Peter Newmark’s text theory, the source text belongs to informative texts. The translation of such text focuses on the accuracy. Chapter 3 contains a careful description of guiding theory and its direction to this translation project. For the reason that the source text is categorized into informative text, the translator adopts Newmark’s “communicative translation” strategy as guidance. Chapter 4 concludes with the experience and lessons from the translation as well as the problems to be resolved.Key words: translation project report; informative text; communicative translation; translation skillsAcknowledgementsUpon the completion of the project report, I would like to express my sincere gratitude to all the people who have helped me a lot in the two years.First of all, I would like to offer my deepest gratitude to my supervisor, Ms. Xia Xindong, who is very amiable and patient. She has spent much time reading through each of my draft and pointed out mistakes in the paper patiently. With her enlightening instructions and careful modifications, I have finished my paper.I also would like to express my heartfelt gratitude to all the teachers who have taught me over the past two years. They helped me to know translation better. Their words and deeds also have enormous influences on the formation of my personality.Moreover, I am deeply indebted to my parents and my friends, who are very considerate and kindhearted. They have accompanied and encouraged me in the writing of the translation project.Last but not least, my indebtedness also goes to those who are willing to spend their time and energy in reading this paper.CONTENTS摘要....................................................................................................................... i i Abstract . (iii)Acknowledgements .................................................................................................. i v Chapter 1 General Introduction (1)1.1Background of the Report (1)1.2Objectives of the Report (2)1.3Structure of the Report (2)Chapter 2 An Introduction to the Source Text (3)2.1About the Author (3)2.2 About the Source Text (4)2.2.1 Publishing Facts of the Source Text (4)2.2.2 Content of the Source Text (4)2.2.3 Linguistic Feature of the Source Text (5)Chapter 3 Theoretical Basis, Translation Difficulties and Solutions (6)3.1 Guiding Theory (6)3.1.1 Introduction to Communicative Translation (6)3.1.2 Application of Communicative Translation (7)3.2 Translation Difficulties (9)3.3 Translation Methods (11)3.3.1 Inversion (11)3.3.2 Conversion (12)3.3.3 Amplification (14)3.3.4 Sentence Division (15)Chapter 4 Conclusion (17)4.1 Lessons Learned from the Translation Practice (17)4.2 Problems to be Resolved (18)References (19)Appendix I Source Text (20)Appendix II 中文译文 (36)Chapter 1 General IntroductionThis chapter makes an introduction to the translation project, involving project background, objectives and structure of the report.1.1Background of the ReportAccording to a survey, most college students nowadays belong to the only child group. Those spoiled children tend to be self-centered and always fail to take others’ feelings into account. When they go to college, they find it hard to get on well with their roommates. In recent years, the media reported several tragic cases which resulted from disharmonious relationship among roommates. Since there are tragic accidents happening in dormitory, people begin to pay more attention to college students’ mental health. As for a generation of the only child, many college students have problems with people and some don’t even know how to interact with others. It is necessary for college students to gain some knowledge of interpersonal communication to deal with tricky things in their life. Thus, based on the translation of Chapter 6 of the book You’re the Only One I Can Tell, the significance of the project is mainly embodied in the following two aspects: firstly, it can make college students realize the subtlety of interpersonal communication and call their attention to behave themselves. Besides, by translating the book, it is hoped to instruct the translation practice and provide guidance for others in the future.This book is not like those theory-oriented ones. It offers many real-life examples which is easy to understand and more instructive. From casual chatting to intimate confiding, from talking about problems to telling what you had for dinner, Tannen uncovers the patterns of communication and miscommunication that affect friendships at different points in our lives. She shows how even the best of friends—with the best intentions—can say wrong things, and how words can repair the damage done by words. Through Tannen’s insight, humor, and ability to present pitch-perfect real-life dialogues, readers will see themselves and their friendships on every page. So, to translate this book will provide references for college students to better understand one another.1.2Objectives of the ReportThe translation report is based on the Chapter 6 named “Too Close for Comfort” which deconstructs the ways in which women friends talk and how those ways can bring friends closer or pull them apart. The project helps readers grasp the notion of “cutoffs” and “poaching” in friendship which are rarely realized by them and makes them understand friendship better. The translation of this text also aims to explain the multiple roles of friendships and to benefit college students who want to gain some knowledge of interpersonal communication from real-life examples. In addition, it is hoped that the translation of the text can help the author to understand Peter Newmark’s communicative translation better and make a summary of two-year studies as a postgraduate.1.3Structure of the ReportThe translation report includes the following chapters. Chapter 1 makes an introduction to the translation project, which involves project background, objectives and structure of the report. Chapter 2 gives a brief introduction to the author and an analysis of the source text, containing publishing information and main contents of the original. Chapter 3 offers a detailed description of “communicative translation” theory, followed by its guidance to this translation project. At the same time, this chapter also points out the difficulties encountered in the translation and the application of translation methods. Chapter 4 is the conclusion, which summarizes the lessons learnt from the translating process and the problems left to be solved.Chapter 2 An Introduction to the Source TextThis chapter is about the author and the analysis of the source text, containing publishing information and main contents of the original.2.1 About the AuthorYou’re the Only One I Can Tell: Inside the Language of Women’s Friendships is written by Deborah Tannen, who is an American academic and professor of linguistics at Georgetown University in Washington, D.C..Deborah Tannen focuses on the expression of interpersonal relationships especially in the conversational interaction. Tannen has researched conversational interaction and style differences at various levels and related to different situations, involving differences in conversation styles in connection with gender and cultural background. Particularly, Deborah Tannen has done many gender-linked researches and writing which put stress on miscommunications between men and women.Tannen also wrote some general-audience books about interpersonal communication and public discourse. She became a household name in the United States after the book You Just Don't Understand: Women and Men in Conversation, which was published in 1990. It has been on the New York Times Best Seller list for almost four years (eight months at No.1) and it was rendered into 30 other languages. She has also written several other books, such as:That's Not What I Meant!: How Conversational Style Makes or Breaks Relationships(published by William Morrow Paperbacks in 2011);The Argument Culture: Stopping America's War of Words (published by Ballantine Books in 1999); andI Only Say This Because I Love You: Talking to Your Parents, Partner, Sibs, and Kids When You're All Adults(published by Ballantine Books in 2002).2.2 About the Source Text2.2.1 Publishing Facts of the Source TextIn 2017, You’re the Only One I Can Tell: Inside the Language of Women’s Friendships was first published in the United States by Ballantine Books and in Great Britain by Virago Press. The Wall Street Journal and The Washington Post highly recommended the book. ISBN:9781101885802. Up to now, there is no Chinese version published.2.2.2 Content of the Source TextFriendship is to us what sunshine to trees. Friendship acts as multiple roles in our lives. Sometimes, friends instruct and encourage us like a mentor or a therapist; sometimes, friends take good care of us like a mother or a big sister. Now that friendship is so important, we should treasure it carefully. The goal of the book You’re the Only One I Can Tell: Inside the Language of Women’s Friendships is to help readers understand women’s friendships—how they work or fail, how they help and hurt, and how we can make them better.This book also aims to figure out what it means to be a friend and how we connect to other people. Apart from some occasional examples from novels and short stories, all the examples which the author gave are based on real ones.Though Deborah Tannen focuses on women’s friendships, but some of what she writes might also be true of friendships between women and men, and among men.In the chapter 6 “Too Close for Comfort”, Deborah Tannen explains friendship is like a double-edged sword which is “for your growth” but also “ for your pruning”. Especially when a friendship gets too close, it is more likely to be for your pruning. The translation project selects chapter 6 (10000 words) as the source text which gives a detailed introduction to “cutoffs” and “poaching” and makes some analyses.2.2.3 Linguistic Feature of the Source TextPeter Newmark is a famous British translation theorist, who classified texts into three categories: expressive text, informative text and vocative text on the basis of Karl Buhler’s theory of language and Katharina Reiss’s typology.According to Newmark, informative texts include textbooks, memos, reports, papers and so on, and put stress on the external situation, the topic and the reality beyond the language(Newmark, 1988, p.40), therefore, this type of text is to convey the information and mainly focuses on the content or topic. The target translation of this type calls for receptors’ response and understanding. Thus, Newmark advised adopting the approach of communicative translation, attempting to exert an effect on its receptors as close as possible to that obtained on the readers of the source text and stress the truth and accuracy during the translating process. In terms of this aspect, Newmark’s opinion is similar to Eugene Nida’s dynamic equivalence, that’s, the readers of a translated text should be able to comprehend it to the point that they can conceive of how the original readers of the text must have understood and appreciate it.(Nida,1982, p. 118)In the book You’re the Only One I Can Tell: Inside the Language of Women’s Friendships, Tannen applies case-study method by interviewing more than 80 women from all over the word ranging in age from 9-97 to explore how patterns of communication and miscommunication have influences on friendships; and the language of the source text is characterized by concision and dialogues. As is known, the focus of an informative text is to deliver plain facts or referential content and topic. The source text can be categorized into the informative text. “The target text (TT) of an informative text should transmit the full referential or conceptual content of the source text (ST). The translation should be in plain prose, without redundancy and with the use of explication when required.”(Munday, 2001, p.73) Thus, in the translation of You’re the Only One I Can Tell: Inside the Language of Women’s Friendships, the translator should pay attention to the linguistic differences and apply various translation skills so that the version is more understandable and readable for Chinese readers.Chapter 3 Theoretical Basis, Translation Difficulties and SolutionsThis chapter contains a careful description of guiding theory and its direction to this translation project. For the reason that the source text is categorized into informative text, the translator adopts Newmark’s “communicative translation” strategy as guidance.3.1 Guiding TheoryAccording to Newmark’s text typology, the source text is under the category of informative text. The focus of an informative text is to deliver plain facts, logical or referential content and topic. According to Katherina Reiss, the ideal translation would be one “in which the aim in the target language is equivalence as regards the conceptual content, linguistic form and communicative function of a source language text.”(Reiss, 1987, p.112) Hence, the translator selects the communicative translation theory of Peter Newmark as the guiding theory of the thesis, where the translator attempts to exert the same effect on the target text readers as the original produced on the source text readers to guarantee the target text readers can receive the same meaning as readers of the original language.3.1.1 Introduction to Communicative TranslationPeter Newmark is an English professor of translation at the University of Surrey. He is renowned for Approaches to Translation, About Translation and A Textbook of Translation and so on. He put forward two translation models: semantic translation and communicative translation. In A Textbook of Translation, he noted “while semantic translation is used for expressive texts, communicative translation is for informative and vocative texts” (Newmark, 1988, p.47) According to Newmark, “communicative translation attempts to produce on its readers an effect as close as possible to that obtained on the readers of the original.”(马会娟&苗菊, 2009, p. 33)“Communicative translation addresses itself solely to the second reader, whodoes not anticipate difficulties or obscurities, and would expect a generous transfer of foreign elements into his own culture as well as his language where necessary.”(马会娟&苗菊, 2009, p. 33)Normally, by making and adapting the thought and cultural content of the original，the translator makes the version more easier, smoother, clearer and more idiomatic to read. In this case, the translator has a high degree of freedom to explain the source text, adjust the style, eliminate the ambiguity and even correct the mistake of the original author.3.1.2 Application of Communicative TranslationThis project takes the communicative translation as the guiding theory. According to Newmark ,“communicative translation attempts to render the exact contextual meaning of the original in such a way that both content and language are readily acceptable and comprehensible to the readership.”(Newmark, 2001, p.47)Example 1ST: But friends can also be for your pruning.TT:但是朋友也会使你退步。

林超伦翻译笔记

发生巨大变化 to undergo yet more changes中国将更加遵循……原则 china will bring its own practices in linewith ……拉动世界经济 to provide/give/lend substantial impetus to the world economyrequire 这个词很重要比如“这都需要在国际合作的环境中才能实现”allof the above requires an environment of international cooperation给一个比较叼的说法“中国以敞开大门，张开双手”china has thrown its door wide open, and reached out with open arms 看起来比较还不多的哦，但是一个句子利用了两个open。

表示对下一步工作的继续进行，用continue 什么工作就好了。

有利于推动……的发展 be conductive to the development of sth做到……的统一 strike the balance of ……我们应该清楚地意识到 it is clear to us that保持经济的长盛不衰 perpetuate an economic boom……是有目共睹的 be there for all to see经济形势不是economic situation 而是economic climate国企改革问题、大量失业待业问题、生态环境破坏问题、金融风险问题、腐败问题等需要重点记住，这里不列英语了需要尽快找到解决方法 to require our immediate attention and effective solutions in the shortest time possible盲目发展 blind development调控 regulate这是一个把握分寸的问题 this is an issue of maintaining the right balance上市 seek listing on the stock market在金融全球化的潮流中急流勇进 to ride the wave of financial globalization表示数量很多的 a handful of省级银行 provincial level banks 重点看省级的即是怎么表示出来的法人在林超伦的翻译中是legal person，而经过我的查找，corporation和artificial person比较正确而且常见。

Concentration and energy fluctuations in a critical polymer mixture

a rXiv:c ond-ma t/9411013v12Nov1994Concentration and energy ﬂuctuations in a critical polymer mixture M.M¨u ller and N.B.Wilding Institut f¨u r Physik,Johannes Gutenberg Universit¨a t,Staudinger Weg 7,D-55099Mainz,Germany Abstract A semi-grand-canonical Monte Carlo algorithm is employed in conjunction with the bond ﬂuctuation model to investigate the critical properties of an asymmetric binary (AB)polymer mixture.By applying the equal peak-weight criterion to the concentration distribution,the coexistence curve separating the A-rich and B-rich phases is identiﬁed as a function of temperature and chemical potential.To locate the critical point of the model,the cumulant intersection method is used.The accuracy of this approach for determining the critical parameters of ﬂuids is assessed.Attention is then focused on the joint distribution function of the critical concentration and energy,which is analysed using a mixed-ﬁeld ﬁnite-size-scaling theory that takes due account of the lack of symme-try between the coexisting phases.The essential Ising character of the binary polymer critical point is conﬁrmed by mapping the critical scaling operator distributions onto in-dependently known forms appropriate to the 3D Ising universality class.In the process,estimates are obtained for the ﬁeld mixing parameters of the model which are compared both with those yielded by a previous method,and with the predictions of a mean ﬁeld calculation.PACS numbers 64.70Ja,05.70.Jk1IntroductionThe critical point of binary liquid and binary polymer mixtures,has been a subject of abidinginterest to experimentalists and theorists alike for many years now.It is now well established that the critical point properties of binary liquid mixtures fall into the Ising universality class(the default for systems with short ranged interactions and a scalar order parameter)[1]. Recent experimental studies also suggest that the same is true for polymer mixtures[2]–[11].However,since Ising-like critical behaviour is only apparent when the correlation length farexceeds the polymer radius of gyrationξ≫ R g ,the Ising regime in polymer mixtures is conﬁned(for all but the shortest chain lengths)to a very narrow temperature range nearthe critical point.Outside this range a crossover to mean-ﬁeld type behaviour is seen.Theextent of the Ising region is predicted to narrow with increasing molecular weight in a manner governed by the Ginsburg criterion[12],disappearing entirely in the limit of inﬁnite molecular weight.Although experimental studies of mixtures with diﬀering molecular weights appear to conﬁrm qualitatively this behaviour[5],there are severe problems in understanding the scaling of the so-called“Ginsburg number”(which marks the centre of the crossover region and is empirically extracted from the experimental data[13])with molecular weight Computer simulation potentially oﬀers an additional source of physical insight into polymer critical behaviour,complementing that available from theory and experiment.Unfortunately, simulations of binary polymer mixtures are considerable more exacting in computational terms than those of simple liquid or magnetic systems.The diﬃculties stem from the problems of deal-ing with the extended physical structure of polymers.In conventional canonical simulations, this gives rise to extremely slow polymer diﬀusion rates,manifest in protracted correlation times[14,15].Moreover,the canonical ensemble does not easily permit a satisfactory treat-ment of concentrationﬂuctuations,which are an essential feature of the near-critical region in polymer mixture.In this latter regard,semi-grand-canonical ensemble(SGCE)Monte Carlo schemes are potentially more attractive than their canonical counterparts.In SGCE schemes one attempts to exchange a polymer of species A for one of species B or vice-versa,thereby permitting the concentration of the two species toﬂuctuate.Owing,however,to excluded volume restrictions,the acceptance rate for such exchanges is in general prohibitively small, except in the restricted case of symmetric polymer mixtures,where the molecular weights of the two coexisting species are identical(N A=N B).All previous simulation work has therefore focussed on these symmetric systems,mapping the phase diagram as a function of chain length and conﬁrming the Ising character of the critical point[16,17,18].Tentative evidence for a crossover from Ising to meanﬁeld behaviour away from the critical point was also obtained [19].Hitherto however,no simulation studies of asymmetric polymer mixtures(N A=N B) have been reported.Recently one of us has developed a new type of SGCE Monte Carlo method that amelio-rates somewhat the computational diﬃculties of dealing with asymmetric polymer mixtures [20].The method,which is described brieﬂy in section3.1,permits the study of mixtures of polymer species of molecular weight N A and N B=kN A,with k=2,3,4···.In this paper we shall employ the new method to investigate the critical behaviour of such an asymmet-ric polymer mixture.In particular we shall focus on those aspects of the critical behaviour of asymmetric mixtures that diﬀer from those of symmetric mixtures.These diﬀerence are rooted in the so called‘ﬁeld mixing’phenomenon,which manifests the basic lack of energetic(Ising) symmetry between the coexisting phases of all realisticﬂuid systems.Although it is expected to have no bearing on the universal properties ofﬂuids,ﬁeld mixing does engender certain non-universal eﬀects in near-criticalﬂuids.The most celebrated of these is a weak energy-like critical singularity in the coexistence diameter[21,22],the existence of which constitutes afailure for the‘law of rectilinear diameter’.As we shall demonstrate however,ﬁeld mixing has a far more legible signature in the interplay of the near-critical energy and concentration ﬂuctuations,which are directly accessible to computer simulation.In computer simulation of critical phenomena,ﬁnite-size-scaling(FSS)techniques are of great utility in allowing one to extract asymptotic data from simulations ofﬁnite size[23].One particularly useful tool in this context is the order parameter distribution function[24,25,26]. Simulation studies of magnetic systems such as the Ising[25]andφ4models[27],demonstrate that the critical point form of the order parameter distribution function constitutes a useful hallmark of a university class.Recently however,FSS techniques have been extended toﬂuids by incorporatingﬁeld mixing eﬀects[28,29].The resulting mixed-ﬁeld FSS theory has been successfully deployed in Monte Carlo studies of critical phenomena in the2D Lennard-Jones ﬂuid[29]and the2D asymmetric lattice gas model[30].The present work extends this programme ofﬁeld mixing studies to3D complexﬂuids with an investigation of an asymmetric polymer mixture.The principal features of our study are as follows.We begin by studying the order parameter(concentration)distribution as a function of temperature and chemical potential.The measured distribution is used in conjunction with the equal peak weight criterion to obtain the coexistence curve of the model.Owing to the presence ofﬁeld mixing contributions to the concentration distribution,the equal weight criterion is found to break down near theﬂuid critical point.Its use to locate the coexistence curve and critical concentration therefore results in errors,the magnitude of which we gauge using scaling arguments.Theﬁeld mixing component of the critical concentration distribution is then isolated and used to obtain estimates for theﬁeld mixing parameters of the model. These estimates are compared with the results of a meanﬁeld calculation.We then turn our attention to theﬁnite-size-scaling behaviour of the critical scaling op-erator distributions.This approach generalises that of previousﬁeld mixing studies which concentrated largely on theﬁeld mixing contribution to the order parameter distribution func-tion.We show that for certain choices of the non-universal critical parameters—the critical temperature,chemical potential and the twoﬁeld mixing parameters—these operator distri-butions can be mapped into close correspondence with independently known universal forms representative of the Ising universality class.This data collapse serves two purposes.Firstly,it acts as a powerful means for accurately determining the critical point andﬁeld mixing param-eters of modelﬂuid systems.Secondly and more generally,it serves to clarify the sense of the universality linking the critical polymer mixture with the critical Ising magnet.We compare the ease and accuracy with which the critical parameters can be determined from the data collapse of the operator distributions,with that possible from studies of the order parameter distribution alone.It is argued that for criticalﬂuids the study of the scaling operator distri-butions represent the natural extension of the order parameter distribution analysis developed for models of the Ising symmetry.2BackgroundIn this section we review and extend the mixed-ﬁeldﬁnite-size-scaling theory,placing it within the context of the present study.The system we consider comprises a mixture of two polymer species which we denote A and B,having lengths N A and N B monomers respectively.The conﬁgurational energyΦ(which we express in units of k B T)resides in the intra-and inter molecular pairwise interactions between monomers of the polymer chains:N i<j=1v(|r i−r j|)(2.1)Φ({r})=where N=n A N A+n b N B with n A and n B the number of A and B type polymers respectively. N is therefore the total number of monomers(of either species),which in the present study is maintained strictly constant.The inter-monomer potential v is assigned a square-well formv(r)=−ǫr≤r m(2.2)v(r)=0r>r mwhereǫis the well depth and r m denotes the maximum range of the potential.In accordance with previous studies of symmetric polymer mixtures[16,17],we assignǫ≡ǫAA=ǫBB=−ǫAB>0.The independent model parameters at our disposal are the chemical potential diﬀerence per monomer between the two species∆µ=µA−µB,and the well depthǫ(both in units of k B T). These quantities serve to control the observables of interest,namely the energy density u and the monomer concentrationsφA andφB.Since the overall monomer densityφN=φA+φB is ﬁxed,however,it is suﬃcient to consider only one concentration variableφ,which we take as the concentration of A-type monomers:φ≡φA=L−d n A N A(2.3) The dimensionless energy density is deﬁned as:u=L−dǫ−1Φ({r})(2.4) with d=3in the simulations to be chronicled below.The critical point of the model is located by critical values of the reduced chemical potential diﬀerence∆µc and reduced well-depthǫc.Deviations ofǫand∆µfrom their critical values control the sizes of the two relevant scalingﬁeld that characterise the critical behaviour.In the absence of the special symmetry prevailing in the Ising model,oneﬁnds that the relevant scalingﬁelds comprise(asymptotically)linear combinations of the well-depth and chemical potential diﬀerence[21]:τ=ǫc−ǫ+s(∆µ−∆µc)h=∆µ−∆µc+r(ǫc−ǫ)(2.5) whereτis the thermal scalingﬁeld and h is the ordering scalingﬁeld.The parameters s and r are system-speciﬁc quantities controlling the degree ofﬁeld mixing.In particular r is identiﬁable as the limiting critical gradient of the coexistence curve in the space of∆µandǫ. The role of s is somewhat less tangible;it controls the degree to which the chemical potential features in the thermal scalingﬁeld,manifest in the widely observed critical singularity of the coexistence curve diameter ofﬂuids[1,22,31].Conjugate to the two relevant scalingﬁelds are scaling operators E and M,which comprise linear combinations of the concentration and energy density[28,29]:M=11−sr[u−rφ](2.6) The operator M(which is conjugate to the orderingﬁeld h)is termed the ordering operator, while E(conjugate to the thermalﬁeld)is termed the energy-like operator.In the special caseof models of the Ising symmetry,(for which s=r=0),M is simply the magnetisation while E is the energy density.Near criticality,and in the limit of large system size L,the probability distributions p L(M) and p L(E)of the operators M and E are expected to be describable byﬁnite-size-scaling relations having the form[25,29]:p L(M)≃a M−1L d−λM˜p M(a M−1L d−λMδM,a M LλM h,a E LλEτ)(2.7a)p L(E)≃a E−1L d−λE˜p E(a E−1L d−λEδE,a M LλM h,a E LλEτ)(2.7b) whereδM≡M−M c andδE≡E−E c.The functions˜p M and˜p E are predicted to be universal,modulo the choice of boundary conditions and the system-speciﬁc scale-factors a M and a E of the two relevantﬁelds,whose scaling indices areλM=d−β/νandλE=1/νrespectively.Precisely at criticality(h=τ=0)equations2.7a and 2.7b implyp L(M)≃a M−1Lβ/ν˜p⋆M(a M−1Lβ/νδM)(2.8a)p L(E)≃a E−1L(1−α)/ν˜p⋆E(a E−1L(1−α)/νδE)(2.8b) where˜p⋆M(x)≡˜p M(x,y=0,z=0)˜p⋆E(x)≡˜p E(x,y=0,z=0)(2.9) are functions describing the universal and statistically scale-invariantﬂuctuation spectra of the scaling operators,characteristic of the critical point.The claim that the binary polymer critical point belongs to the Ising universality class is expressed in its fullest form by the requirement that the critical distribution of theﬂuid scaling operators p L(M)and p L(E)match quantitatively their respective counterparts—the magneti-sation and energy distributions—in the canonical ensemble of the critical Ising magnet.As we shall demonstrate,these mappings also permit a straightforward and accurate determination of the values of theﬁeld mixing parameters s and r of the model.An alternative route to obtaining estimates of theﬁeld mixing parameters is via theﬁeld mixing correction to the order parameter(i.e.concentration)distribution p L(φ).At criticality, this distribution takes the form[29,30]:p L(φ)≃a M−1Lβ/ν ˜p⋆M(x)−sa E a M−1L−(1−α−β)/ν∂∂x (˜p⋆M(x)˜ω⋆(x)),is a function characterising the mixing of the critical energy-like operator into the order parameter distribution.Thisﬁeld mixing term is down on the ﬁrst term by a factor L−(1−α−β)/νand therefore represents a correction to the large L lim-iting behaviour.Given further the symmetries of˜ω(x)and˜p⋆M(x),both of which are even (symmetric)in the scaling variable x[29],theﬁeld mixing correction is the leading antisym-metric contribution to the concentration distribution.Accordingly,it can be isolated frommeasurements of the critical concentration distribution simply by antisymmetrising around φc= φ c.The values of s and r are then obtainable by matching the measured critical func-tion−s∂simply by cutting a B-type polymer into k equal segments.Conversely,a B-type polymer is manufactured by connecting together the ends of k A-type polymers.This latter operation is,of course,subject to condition that the connected ends satisfy the bond restrictions of the BFM.Consequently it represents the limiting factor for the eﬃciency of the method,since for large values of k and N A,the probability that k polymer ends simultaneously satisfy the bond restrictions becomes prohibitively small.The acceptance rate for SGCE moves is also further reduced by factors necessary to ensure that detailed balance is satisﬁed.In view of this we have chosen k=3,N A=10for the simulations described below,resulting in an acceptance rate for SGCE moves of approximately14%.In addition to the compositionalﬂuctuations associated with SGCE moves,it is also nec-essary to relax the polymer conﬁgurations at constant composition.This is facilitated by monomer moves which can be either of the local displacement form,or of the reptation(‘slith-ering snake’)variety[2].These moves were employed in conjunction with SGCE moves,in the following ratios:local displacement:reptation:semi-grandcanonical=4:12:1the choice of which was found empirically to relax the conﬁgurational and compositional modes of the system on approximately equal time scales.In the course of the simulations,a total ofﬁve system sizes were studied having linear extent L=32,40,50,64and80.An overall monomerﬁlling fraction of8φN=0.5was chosen, representative of a dense polymer melt[15].Here the factor of8constitutes the monomeric volume,each monomer occupying8lattice sites.The cutoﬀrange of the inter-monomeric√square well potential was set at r m=whereφ∗is a parameter deﬁning the boundary between the two peaks.Well below criticality,the value of∆µcx obtained from the equal weight criterion is in-sensitive to the choice ofφ∗,provided it is taken to lie approximately midway between the peaks and well away from the tails.As criticality is approached however,the tails of the two peaks progressively overlap making it impossible to unambiguously deﬁne a peak in the manner expressed by equation3.1.For models of the Ising symmetry,for which the peaks are symmetric about the coexistence concentrationφcx,the correct value of∆µcx can nevertheless be obtained by choosingφ∗= φ in equation3.1.In near-criticalﬂuids,however,the imposed equal weight rule forces a shift in the chemical potential away from its coexistence value in or-der to compensate for the presence of theﬁeld mixing component.Only in the limit as L→∞(where theﬁeld mixing component dies away),will the critical order parameter distribution be symmetric allowing one to chooseφ∗= φ and still obtain the correct coexistence chemical potential.Thus forﬁnite-size systems,use of the equal weight criterion is expected to lead to errors in the determination of∆µcx near the critical point.Although this error is much smaller than the uncertainty in the location of the critical point along the coexistence curve (see below),it can lead to signiﬁcant errors in estimates of the critical concentrationφc.To quantify the error inφc it is necessary to match the magnitude of theﬁeld mixing component of the concentration distribution w(δp L),to the magnitude of the peak weight asymmetry w′(δµ)associated with small departuresδµ=∆µ−∆µcx from coexistence:w(δp L)=w′(δµ)(3.2) Now from equation2.10w(δp L)≈ φNφ∗dφδp L(φ)∼L−(1−α−β)/ν(3.3) whilew′(δµ)≈ φNφ∗dφ∂p L(φ)3 m2 2(3.7)where m2and m4are the second and fourth moments respectively of the order parameter m=φ− φ .To the extent thatﬁeld mixing corrections can be neglected,the critical order parameter distribution function is expected to assume a universal scale invariant form. Accordingly,when plotted as a function ofǫ,the coexistence values of G L for diﬀerent system sizes are expected to intersect at the critical well depthǫc[26].This method is particularly attractive for locating the critical point inﬂuid systems because the even moments of the order parameter distribution are insensitive to the antisymmetric(odd)ﬁeld mixing contribution. Figure2displays the results of performing this cumulant analysis.A well-deﬁned intersection point occurs for a value G L=0.47,in accord with previously published values for the3D Ising universality class[36].The corresponding estimates for the critical well depth and critical chemical potential areǫc=0.02756(15)∆µc=0.003603(15)It is important in this context,that a distinction be drawn between the errors on the location of the critical point,and the error with which the coexistence curve can be determined.The uncertainty in the position of the critical point along the coexistence curve,as determined from the cumulant intersection method,is in general considerably greater than the uncertainty in the location of the coexistence curve itself.This is because the order parameter distribution function is much more sensitive to small deviations oﬀcoexistence(due toﬁniteǫ−ǫcx orﬁnite ∆µ−∆µcx)than it is for deviations along the coexistence curve,(ǫand∆µtuned together to maintain equal weights).In the present case,weﬁnd that the errors on∆µc andǫc are approximately10times those of the coexistence valuesǫcx and∆µcx near the critical point.The concentration distribution function at the assigned value ofǫc and the corresponding value of∆µcx,(determined according to the equal weight rule withφ∗=<φ>),is shown inﬁgure3for the L=40and L=64system sizes.Also shown in theﬁgure is the critical magnetisation distribution function of the3D Ising model obtained in a separate study[37]. Clearly the L=40and L=64data diﬀer from one another and from the limiting Ising form.These discrepancies manifest both the pure antisymmetricﬁeld mixing component of the true(ﬁnite-size)critical concentration distribution,and small departures from coexistence associated with the inability of the equal weight rule to correctly identify the coexistence chemical potential.To extract the inﬁnite-volume value ofφc from theﬁnite-size data,it is therefore necessary to extrapolate to the thermodynamic limit.To this end,and in accordance with equation3.6,we have plottedφcx(L),representing theﬁrst moment of the concentration distribution determined according to equal weight criterion at the assigned value ofǫc,against L(1−α)/ν.This extrapolation(ﬁgure4)yields the inﬁnite-volume estimate:φc=0.03813(19)corresponding to a reduced A-monomer densityφc/φN=0.610(3).Theﬁnite-size shift in the value ofφcx(L)is of order2%.We turn next to the determination of theﬁeld mixing parameters r and s.The value of r represents the limiting critical gradient of the coexistence curve which,to a good approxima-tion,can be simply read oﬀfromﬁgure1with the result r=−0.97(3).Alternatively(and as detailed in[29])r may be obtained as the gradient of the line tangent to the measured critical energy function(equation2.11)atφ=φc.Carrying out this procedure yields r=−1.04(6).The procedure for extracting the value of theﬁeld mixing parameter s from the concentra-tion distribution is rather more involved,and has been described in detail elsewhere[29,30]. The basic strategy is to choose s such as to satisfy∂δp L(φ)=−swhereδp L(φ)is the measured antisymmetricﬁeld mixing component of the critical concen-tration distribution[30],obtained by antisymmetrising the concentration distribution about φc(L)and subtracting additional corrections associated with small departures from coexistence resulting from the failure of the equal weight rule.Carrying out this procedure for the L=40 and L=64critical concentration distributions yields theﬁeld mixing components shown in ﬁgure5.The associated estimate for s is0.06(1).Also shown inﬁgure5(solid line)is the predicted universal form of the3D order parameterﬁeld mixing correction−∂u−rφ1−sr p L(E)=p Lsection2).This discrepancy implies that the system size is still too small to reveal the asymp-totic behaviour Nevertheless the data do aﬀord a test of the approach to the limiting regime, via the FSS behaviour of the variance of the energy distribution.Recalling equation2.14, we anticipate that this variance exhibits the same FSS behaviour as the Ising susceptibility, namely:L d( u2 −u2c)∼Lγ/ν(3.10) By contrast,the variance of the scaling operator E is expected to display the FSS behaviour of the Ising speciﬁc heat:L d( E2 −E2c)∼Lα/ν.(3.11) Figure9shows the measured system size dependence of these two quantities at criticality.Also shown is the scaled variance of the ordering operator L d( M2 −M2c)∼Lγ/ν.Straight lines of the form Lγ/νand Lα/ν,(indicative of the FSS behaviour of the Ising susceptibility and speciﬁc heat respectively)have also been superimposed on the data.Clearly for large L,the scaling behaviour of the variance of the energy distribution does indeed appear to approach that of the ordering operator distribution.4Meanﬁeld calculationsIn this section we derive approximate formulae for the values of theﬁeld mixing parameters s and r on the basis of a meanﬁeld calculation.Within the well-known Flory-Huggins theory of polymer mixtures,the mean-ﬁeld equation of state takes the form:∆µ=1N Bln(1−ρ)−2zǫ(2ρ−1)+C(4.1)In this equation,z≈2.7is the eﬀective monomer coordination number,whose value we have obtained from the measured pair correlation function.ρ=φ/φN is the density of A-type monomers and the constant C is the entropy density diﬀerence of the pure phases,which is independent of temperature and composition.In what follows we reexpressρby the concen-trationφ.The critical point is deﬁned by the condition:∂∂φ2∆µc=0(4.2) where∆µc=∆µ(φc,ǫc).This relation can be used to determine the critical concentration and critical well-depth,for which oneﬁndsφc1+1/√ǫc=z4N A N BN A+√where the expansion coeﬃcients take the formr ′=−2z (2φc φN b =(1+√3√k )4φ+−φ−(4.6)where φ−and φ+denote the concentration of A monomers in the A-poor phase and A-rich phases respectively.Thus to leading order in ǫ,the phase boundary is given by :∆µcx (ǫ)=∆µc +r ′δǫc +···(4.7)Consequently we can identify the expansion coeﬃcient r ′with the ﬁeld mixing parameter r (c.f.equation 2.5)that controls the limiting critical gradient of the coexistence curve in the space of ∆µand ǫ.Substituting for ∆µc and ǫc in equation 4.7and setting k =3,we ﬁnd r =−1.45,in order-of-magnitude agreement with the FSS analysis of the simulation data.In order to calculate the value of the ﬁeld mixing parameter s ,it is necessary to obtain the concentration and energy densities of the coexisting phases near the critical point.The concentration of A-type monomers in each phase is given byδφ±=φ±−φc =± b −2acδǫ2−φc =−2acδǫ2 z s +z (2ρ−1)2 =−φN φN −1)2+rδφ−2z2−u (φc )=−2za5zb δǫ+···(4.11)Now since (1−rs ) M = δφ −s δu vanishes along the coexistence line,equations 4.9and4.11yield the following estimate for the ﬁeld mixing parameter s :s = δφ 5zb 1+r cφN 20z √20z √[30].The sign of the product rs diﬀers however from that found at the liquid-vapour critical point.In the present context this product is given byrs10(√NB)2N A N B(4.13)However an analogous treatment of the van der Waalsﬂuid predicts a positive sign rs,in agreement with that found at the liquid vapour critical point[29,30].5Concluding remarksIn summary we have employed a semi-grand-canonical Monte Carlo algorithm to explore the critical point behaviour of a binary polymer mixture.The near-critical concentration and scal-ing operator distributions have been analysed within the framework of a mixed-ﬁeldﬁnite-size scaling theory.The scaling operator distributions were found to match independently known universal forms,thereby conﬁrming the essential Ising character of the binary polymer critical point.Interestingly,this universal behaviour sets in on remarkably short length scales,being already evident in systems of linear extent L=32,containing only an average of approximately 100polymers.Regarding the speciﬁc computational issues raised by our study,weﬁnd that the concen-tration distribution can be employed in conjunction with the cumulant intersection method and the equal weight rule to obtain a rather accurate estimate for the critical temperature and chemical potential.The accuracy of this estimate is not adversely aﬀected by the anti-symmetric(odd)ﬁeld mixing contribution to the order parameter distribution,since only even moments of the distribution feature in the cumulant ratio.Unfortunately,the method can lead to signiﬁcant errors in estimates of the critical concentrationφc,which are sensitive to the magnitude of theﬁeld mixing contribution.The inﬁnite-volume value ofφc must therefore be estimated by extrapolating theﬁnite-size data to the thermodynamic limit(where theﬁeld mixing component vanishes).Estimates of theﬁeld mixing parameters s and r can also be extracted from theﬁeld mixing component of the order parameter distribution,although in practice weﬁnd that they can be determined more accurately and straightforwardly from the data collapse of the scaling operators onto their universalﬁxed point forms.In addition to clarifying the universal aspects of the binary polymer critical point,the results of this study also serve more generally to underline the crucial role ofﬁeld mixing in the behaviour of criticalﬂuids.This is exhibited most strikingly in the form of the critical energy distribution,which in contrast to models of the Ising symmetry,is doubly peaked with variance controlled by the Ising susceptibility exponent.Clearly therefore close attention must be paid toﬁeld mixing eﬀects if one wishes to perform a comprehensive simulation study of criticalﬂuids.In this regard,the scaling operator distributions are likely to prove themselves of considerable utility in future simulation studies.These operator distributions represent the natural extension toﬂuids of the order parameter distribution analysis deployed so successfully in critical phenomena studies of(Ising)magnetic systems.Provided therefore that one works within an ensemble that aﬀords adequate sampling of the near-criticalﬂuctuations,use of the operator distribution functions should also permit detailed studies ofﬂuid critical behaviour. AcknowledgementsThe authors thank K.Binder for helpful discussions.NBW acknowledges theﬁnancial sup-port of a Max Planck fellowship from the Max Planck Institut f¨u r Polymerforschung,Mainz.。

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draft 法案,草案Government bill 政府议案to pass a bill, to carry a bill 通过议案to enact a law, to promulgate a law 颁布法律ratification, confirmation 批准law enforcement 法律的实施to come into force 生效decree 法令clause 条款minutes 备忘录report 判例汇编codification 法律汇编legislation 立法legislator 立法者jurist 法学家jurisprudence 法学legitimation 合法化legality, lawfulness 法制,合法legal, lawful 合法的,依法的to contravene a law, to infringe a law, to break a law 违法outlaw, outside the law 超出法律范围的offender 罪犯to abolish 废止,取消rescission, annulment 废除,取消repeal, revocation, annulment 废除(法律) cancellation, annulment, invalidation 废除(合同) cancellation (支票)作废annulment 撤消(遗嘱)repeal rescission 撤消(判决)revocation 撤消immunity 豁免,豁免权disability, legal incapacity 无资格nonretroactive character 不溯既往性prescription 剥夺公权attainder 公民权利的剥夺和财产的没收constitutional law 宪法canon law 教会法规common law 习惯法criminal law 刑法administrative law 行政法civil law 民法commercial law, mercantile law 商法law of nations 万国公法,国际法international law 国际法natural law 自然法labour laws 劳工法fiscal law 财政法Civil Suit Law, Code of civil law 民事诉讼法Criminal Law 刑事诉讼法Military Law 军法Conscript Law 兵役法Copyright Law 著作权法penal code 刑法典code of mercantile law 商法典civil rights 民事权利,公民权利right of asylum 避难权human rights, rights of man 人权(customs) duties 关税death duty, death tax 遗产税royalties 版税法律英语词汇2009-12-20 20:59:34| 分类：专业英语词汇阅读8 评论0 字号：大中小订阅管辖：jurisdiction级别管辖：jurisdiction by level地域管辖：territorial jurisdiction移送管辖：referral jurisdiction指定管辖：designation jurisdiction审判组织: trial organization回避withdrawal诉讼参加人participants in court诉讼当事人parties in court诉讼代理人agents ad litem期间：time periods送达service调解conciliation财产保全property preservation先予执行preliminary execution妨碍民事诉讼的强制措施：compulsory measures against impairment of civil actions 诉讼费：litigation costs第一审普通程序ordinary procedure of first instance第二审程序procedure of second instance起诉bring a lawsuit受理accept a case开庭审理trial in court诉讼中止suspension of a lawsuit诉讼终止conclusion of a lawsuit判决judgment裁定order简易程序summary procedure特别程序special procedure选民资格案件cases concerning certificates of voters宣告失踪proclamation of a person as missing宣告死亡proclamation of a person as dead无民事行为能力incompetent for civil conduct限制行为能力limited capacity for civil conduct无主财产property of ownerless执行申请application for execution执行移转referral of execution仲裁arbitration司法协助judicial assistanceAabsolute proof 绝对证明absolute property 绝对财产（权）abstract of title 产权书摘要acceleration clause 提前（偿还）条款acceptance 承诺accident report 事故报告accident insurance 意外保险accusation 指控；控告accusatorial procedure 控告程序accusatorial process of proof 控告证明过程（程序）accusatorial system 控告或诉讼程序accused 被指控者accuser 控告人acknowledgement 认知(书)acquittal 无罪判决act 条例；作为Act for the prevention of Frauds and Perjuries 《预防诈欺和伪证条例》action 诉讼；作为actual losses 实际损失adjudication 裁决；裁定administrative law 行政法administrative law judge 行政法法官administrative procedure 行政程序administrator 管理人；监管人admissible 可采的admissibility 可采性admit 采用；允许adoption 收养adulterous conduct 通奸行为ad valorem property tax 从价财产税adversarial hearing 对抗式听证会adversarial process 对抗式程序adversary 对手adversary trial system 对抗式（或抗辩）审判制度advocacy 出庭辩护；诉讼代理advocate 辩护人；诉讼代理人affidavit 正式书面陈述affirm 维持（原判）affirmation 保证书；证词affirmative 确保的agency （行政）机关agency action 机关（行政）机关agreed upon remedies 补救协议agreement 协议agreement-as-written 书面协议agreement -in-fact 事实协议alibi 阿里白（不在犯罪场的证明）alienation of affection 离间夫妻关系allegation 声称；指控allege 诉称；指控alleged offense 所控罪行alternate juror 替补陪审员amendment 修正案American Bar Association 美国律师协会American Law Institute 美国法学会analogy 类推Anglo-American Legal System英美法系anonymous accusation匿名控告appeal上诉appear出庭appellant上诉人appellate action上诉行为appellate court上诉法院appellee被上诉人appealer上诉人appropriate拨款appurtenant附属物arbiter仲裁人arbitrary武断的arbitration仲裁arraignment初审array陪审员名单arrest逮捕arrest warrant逮捕令（证）arrestee被捕人article条款，文章article of authority授权条款articles of confederation《联帮条例》articles of incorporation公司组织章程artificial person法人Asian American legal defense and education fund亚裔美国人法律辩护与教育基金会assault意图或威胁伤害assert主张，宣称asset资产assistant attorney助理法官associate judge副法官associate justice副大法官assumption违约合同，违约赔偿之诉assumption 假定attempt意图，企图attempted escape逃脱未遂attestation证词attorney代理人，律师attorney at law律师attorney general检察长authentication鉴定authority权力，法源，权威性依据automobile insurance机动车保险automobile tort机动车侵权行为autonomy自治（权）Bban禁令，禁止banishment流放bankruptcy 破产bankruptcy discharge破产债务解除bankruptcy judge破产法官bar律师职业bar association律师协会barrister出庭律师battery殴打bench trial法官审beneficiary受益人benefit收益，福得bigamy重婚罪bill of lading提单bill of right《人权法案》bind over具保，具结binder临时保险单binding有约束力binding contract有约束力的合同binding force约束力binding interpretation有约束力的解释black-letter law（普通接受之基本原则的）黑体字法black nation bar association全美黑人律师协会blue sky law蓝天法（关于股票买卖控制的法律）Board of Governors（ABA）（美国律师协会的）董事会body of law 法体bond 债券；保释金bond instrument 债券契据branding 鞭笞breach 违约；破坏bride 贿赂bribery 贿赂（罪）bright-line test 明显界限检验标准broker 中间人brokerage fee 佣金；中介费brother-sister corporation 兄弟公司；姊妹公司Bulk Sales Act《大宗销售条例》burden 责任burden of going forward with the evidence 先行举证责任burden of persuasion 说服责任；证明责任burden of producing evidence 举证责任burden of proof 证明责任burglary入室盗窃（罪）business corporation实业公司business law 实业法business organization 实业组织buy-out agreement（股权）承买协议buy-sell agreement（股权）买卖协议bylaws（内部）章程CCalifornia Penal Code《加州刑法典》capital account 资本帐户capital crime 可判死刑罪capital punishment 死刑capital surplus 资本盈余capitation tax 人头税career criminal 职业罪犯career judiciary 职业法官case briefing 案情摘要case-in-chief 主诉case law 判例法case method 案例教学法case report 判决报告case reports 判例汇编casualty insurance （意外伤害）保险catalog 商品目录（单）certificate 证书certificate of existence 实体存在证明（书）challenge 置疑；挑战challenge for cause有理回避chancery court 衡平法院charging instrument 控告文件checks and balances 制衡（原则）chief judge 首席法官chief justice 首席大法官child abuse 虐待儿童circuit court 巡回法院circuit judge 巡回法官circumstantial evidence 旁证；情况证据citation 引证cite 援引；传讯civil court 民事法civil forfeiture 民事罚没civil law 民法Civil Law Legal System 民法体系civil liability 民事责任civil Liberty 民事自由civil Litigation民事诉讼civil procedure 民事诉讼程序civil suit民事诉讼Civil trial 民事审判法律英语词汇（2）2009-12-20 21:02:17| 分类：专业英语词汇阅读10 评论0 字号：大中小订阅Civil right 民权Civil right law 民权法Civil War Income Tax Act 《内战所得税条例》Claim 诉讼请求，索赔Classification of law 法律分类Close corporation内部持股公司Closely held corporation 内部持股公司Closing 终结，成交，结帐Closing argument 最后论述Closing statement成交声明Code 法典Code of Judicial Conduct 《法官行为准则》Codify 编成法典Co-felon 共同重罪犯Cohabitation 同居Collateral contract 附属合同Collegiate bench 合议席Collegiate panel 合议庭Commercial clause 商务条款，贸易条款Commercial law 商法Commercial paper 商务文件Commission佣金Commit 交托，犯（罪）Commitment 犯罪，许诺，委托Commitment of financing 融资许诺Common law 普通法Common law damages 普通法赔偿金Common law legal system(family) 普通法法系Common law marriage 普通法婚姻Common property 共同财产Common stock 普通股票Community property 共同财产Comparative law 比较法Comparative negligence 比较过失Compensation 赔偿（金）Compensatory damage 应予赔偿之损害Competence 管辖权限Competency 有效性Complaint 控告，申诉Comprehensive Drug Abuse Prevention and Control Act 《滥用毒品的综合预防与控制条例》Compulsory license 强制性许可Concur附条件地同意Concurring opinion 并存（判决）意见Confer 授与Conference 协商会议Confidential information 保密信息Confiscation 没收Conflict law 冲突法Congress 国会Consent 同意，认可Consideration 对价，约因Constitution 宪法Constitutional Convention 制宪会议Constitutional law 宪法Constitutional tort 宪法性侵权Constitutionality 合宪性Construction （法律的）结构，解释Construe 解释，分析Consultation 磋商Consumer protection statute 消费者保护法律Consumption tax 消费税Continental Law Legal System(or Family) 大陆法系Contingent fee 胜诉酬金Continuance 诉讼延期Contract 合同Contract dispute 合同纠纷Contract formation 合同构成Contract interpretation 合同解释Contract law 合同法Contract performance 合同履行contractor 承包商contravence 触犯;违犯contributory negligence 共同过失controlling law 应适应之法律conversion 非法占有convey 转让conveyance 转让convertible bond 可转换债券conviction 有罪判决convincing evidence 使人信服的证据copyright 版权;著作权corporal punishment肉体刑corporate camsel 公司法律顾问corporate excise tax 公司执照税corporate law 公司法corporation 公司corporation aggregate 合有公司corporation code 公司法典corporation law 公司法corporation sole 独有公司corpus 尸体;本金Council on legal Education Opportunities 法律教育机会委员会counselor (法律)顾问;律师counselor-at-law 律师court 法院;法官court decision 法院判决court fee 诉讼费court of appeals 上诉法院court of chancery 衡平法法院court of claims 索赔法院court of customs and Patent Appeals 关税及专利上诉法院court of domestic relations 家庭关系法院court opinion 法院判决意见courtroom 法庭coverage 保险范围crime 犯罪crime code 刑法典crime homicide 有罪杀人crime justice system 刑事司法系统crime law 刑法crime liability 刑事责任crime procedure 刑事诉讼程序cross-examination 交叉盘问;盘诘cruel and unusual punishment 残忍和非常的刑罚cumulative evidence 累计证据curative 临时监护的curriculum guide 课程指南custody 监护custom duty 关税customary law 习惯法customary practice 惯例customs court 关税法院Ddamage 损害;损伤damage claim 损害赔偿请求damages 损害赔偿金deadlocked jury 僵局陪审团death penalty 死刑death tax 遗产税debenture 债单(券)debt securities 债权证券decide a case 判案deed 契约deed book 文契汇编defamation 诽谤default 不履行;违约defendant 被告人defence 辩护defence attorney 辩护律师defense's case-in-chief 辩护方主讼deficiency judgment 不足额判决degrees of murder (恶意)杀人罪的等级delegation 授权delegated legislation 授权立法deliberate intention 故意deliberation (陪审团)评议demonstrative evidence 示意证据deprivation 剥夺derogatory treatment of the work 对作品的贬毁性处理(或使用) designs 设计detract 毁损;贬低developer (土地)开发商dicta 判决附带意见dignity 尊严direct evidence 直接证据direct examination 直接盘问direct tax 直接税disa bility insurance 残疾保险disabled dependent child 无谋生能力的残疾儿童discharge 解雇;释放discount 贴现;折扣discovery 要求告知discrete risk transfer product 离散性风险转移(保险)产品discretion 自由裁量权discriminatory 歧视性税收dispense 执行;施行dispute 争议;纠纷disposition 处置(权)dissent 异议;反对dissenting opinion 异议;反对意见dissolution 解散distort 歪曲;误解district attorney 地区检查官database right 数据权dividend 股息division of title 产权分割divorce 离婚docket 备审案件目录doctrine 法则;原则doctrine of constitutional supremacy 宪法至上原则doctrine of Maranda Warnings 米兰达忠告原则document 文件;文书document of title 产权证书domant Commerce Clause 休眠的"贸易条款"domicile 住所地double jeopardy 一罪二审draft 起草;草拟draftman 起草者drug trade 毒品交易drug trafficking 毒品交易dry run 干转;排练due diligence 适当努力due process 正当程序Due Process Clause 正当程序条款due process test 正当程序检验标准duration 期限duress 强迫;胁迫duty 义务;关税duty of care 照看义务法律英语词汇（3）2009-12-20 21:03:22| 分类：专业英语词汇阅读16 评论0 字号：大中小订阅earnest money 定金easyment 地役权ecclesiastical court 宗教法庭economic law 经济法effective date 生效日期effective time 生效时间element of crime 犯罪要素(件)empower 授权enact 制定;颁布en banc 全体法官出庭审判encroachment 侵占encumbered property 抵押财产enforce 实施；执行enforceable 可强制执行的enforceability 可执行性enforcement of Law 执法English-American Legal System (or Family) 英吉利法系enjoin(衡平）强制令entail 限定继承entity 实体environmental impact statement 环境影响报告environmental Law 环境保护法Environmental protection Agency(EPA) 环境保护局environmental quality 环境质量equal protection clause 平等保护条款equitable relief 衡平救济equity 衡平法equity Law 衡平法equity precedent 衡平法判例equity securities 产权证券；衡平证券error 过错escape 逃走；逃脱escrow 第三者保存合同essential justice 实质公正estate财产；遗产estate tax 遗产税ＥＵDirective 欧盟指令evaluate 评价evict 逐出（租户）evidence 证据evidentiary presumption 证据推定evidentiary rule 证据规则ex aequo at bono 公平且善良examine 检查；盘问examination 检查；盘问exception 例外exception clause 例外条款excise tax 执照税exclude 排除exclusive listing 读家上市exclusive right 排他性权利exclusive tax situs 唯一征税地点excusable homicide 可宽恕之杀人execute 执行；签属execution 执行executive acts 行政条例executive branch 行政部门executive order 行政命令executor (遗嘱）执行人executor of estate 遗产执行人exemption 免除；豁免exhibit 展示物（证）exigent circumstance 紧急情况existing securities 上市证券exparte 单方面的expectation damages 预期赔偿金expert 专家（证人）expert testimony 专家证言expert witness 专家证人express contract 明示合同express statutory provision 法律明文规定express warranty 明示保证（保修）ex rel 依据告发face amount 面颊face value 面植facilitate 促使：利于fact 事实fact in issue 争议事实factor 因素；代理商Factors Lien Act 《代理商留置权条例》Fair trial 公平审判false imprisonment 非法拘禁family law 家庭法fault 过错fault principle 过错原则feasibility study 可行性研究Federal Administrative Procedure Act 《联邦行政程序》Federal Antitrust Law 《联邦犯托拉斯法》federal convention 联邦制宪会议federal crime of murder 联邦杀人罪Federal Housing Act 《联邦住房条例》Federal Income Tax Act 《联邦所得税条例》federal judge 联邦法官Federal rules of civil procedure 《联邦民事诉讼规则》Federal rules of criminal procedure 《联邦刑事诉讼规则》Federal rules of evidence 《联邦证据规则》Federal securities act 《联邦证券条例》federal supremacy 联邦至上（原则）Federal tort claims act 《联邦侵权索赔条例》felon 重罪犯felony 重罪felony-murder 重罪杀人fiduciary 受托人file 档案；注册file a petition 呈交诉状；提出请求fine 罚金fingerprint 手印fire insurance 火灾保险fire protection 消防first degree murder 一级谋杀first instance 一审fixture （不动产）附属物flogging 烙印force of law 法律效力forcible felony 暴力性重罪foreign exchange risk 外汇风险forfeiture 没收；罚没form contract 格式合同form of evidence 证据的形式formal adjudication 正式裁决formal rulemaking 正式规则制定formation 构成；鉴定franchise tax 特许经营税fraud 诈欺free enterprise system 自由企业制度free movement of goods 自由物流，货物的自由流通freedom of choice 选择自由frustrate 使受挫折fundamental law 基本法fundamental right 基本权利法律英语词汇（4）2009-12-20 21:04:29| 分类：专业英语词汇阅读12 评论0 字号：大中小订阅general acceptance standard (科学证据的)公认标准general partnership 一般合伙general property 一般财产（权）general provisions 总则gerontocratic 老人统治的gift tax 赠予税government tort 政府侵权（行为）grant of power 授权gross negligence 严重过失group insurance 团体保险guarantee 担保guardian 监护人guardianship 监护权guidelines for sentencing 量刑指南guilt 有罪guilty 有罪的guilty 有罪答辩Hhabitual offender 惯犯hail insurance 冰雹保险handcuff 手铐handwriting 笔迹health insurance 健康保险health regulation 卫生法规hearing 听证（会）hearing of jury 陪审团听审hearsay 传闻证据heir 继承人hierarchy 等级制度high crime 重罪hold 认定；裁定holding 认定；裁定holding device 拥有手段（形式）homicide 杀人（罪）homosexuality 同性恋house counsel （公司）专职法律顾问husband-wife relationship 夫妻关系husband-wife tort 夫妻侵权（行为）IId. 同上identification 认定；确认身份；身份证ignore 忽视；驳回illegal 非法的；违法的immaterial 无实质性的immigration law 移民法immovable property 不动产immunity 豁免（权）impair 损害；削弱impeachment 弹劾；质疑implementation 实施；执行implied contract 默认合同implied warranty 默认保证（保修）imprisonment 监禁imputable 可归罪于……的imputation 归罪in re 关于；案由in recess 休庭in rem 对物的（诉讼）in session 开庭inadmissible evidence 不可采证据incarceration 禁闭；监禁incest 乱伦income tax 所得税Income Tax Act 《所得税条例》income tax on corporations 公司所得税income tax on individuals 个人所得税incompetence 无行为能力；无法律资格incompetent 无行为能力的；无法律资格的incorporation 法人；公司；组成公司incorporator 公司创办人independent regulatory agency 独立规制机构indicative list 指导性名单indictment 起诉书indirect evidence 间接证据indirect tax 间接税individual choice 个人选择（权）individual freedom 个人自由individual omni competence 个人全权individual proprietorship 个体业主individual right 个人权利ineffective 失效的inequality 不平等infamous 罪恶的；丑恶的inference 推理;推论infliction 处罚informal adjudication 非正式裁决informal rulemaking 非正式规则制定information 信息; 控告书infomer 耳目;情报员initial ruling 初步裁定injunction 禁令;强制令injunctive relief 强制救济injure 伤害injustice 不公正innocence 无罪innocent 无罪的;无罪者innocent owner defense 无过错所有人辩护inquiry 调查inquisitiorial system 纠问式诉讼制度insane 精神失常insanity defense 精神失常辩护inspection 检查;审查installment land vendor 分期付款的土地出售人installment plan agreement 分期付款购物协议instruction 指示instrument 文件insurable interest 可保利益insurable loss 可保损失insurance agent 保险代理商insurance binder 临时保单insurance broker 保险中间人insurance card 保险卡insurance coverage 保险范围insurance law 保险法insurance policy 保险单;险种insurance premium 保险费insurance proceeds 保险收益insurance product 保险项目insured 被保险人insurer 保险人intangible 无形的intangible damage 无形损害intangible property 无形财产intangible personal property 无形的人身财产(权)inter alia 除了别的以外interfere 干涉;侵犯interlocutory injunction 临时强制令;(诉讼)中间的强制令intermediate appellate court 中级上诉法院intermetional business 调解interrogation 国际商务intentional 故意的intentional tort 故意侵权行为interest 利息;权益;利益interest rate risk 利率风险interview 询问invalid 无效的;不合法的invalidate 使无效invasion of privacy 侵犯隐私权investigation 侦查;调查investment 投资investment portfolio risk 投资风险组合investment securities 投资证券irrelevancy 无相关性irrelevant 不相关的irrelevant evidence 无相关性证据irrevocable 不可撤销的irrevocable life insurance trust 不可撤销的人寿保险信托itinerant judge 巡回法官法律英语词汇（5）2009-12-20 21:05:16| 分类：专业英语词汇阅读19 评论0 字号：大中小订阅Jjoint tenancy 共同租借(权)joint venture 合资企业joint venture corporation合资公司joint venture with Chinese and foreign investment中外合资企业judge法官judge-made law法官立法judge's chamber法官室judge's charge to jury法官对陪审团的指令judge's instruction to jury法官对陪审团的指示judgment判决，裁定judicial branch司法部门judicial clerkship法院书记员职位judicial decision 法官职位judicial district司法区judicial interpretation司法解释judicial notice司法任职judicial opinion法官判决意见judicial review司法审查judicial scrutiny司法检查judicial subjectivity审判主观性judicial system法院系统judiciary法官jurisdiction司法管辖区jurisprudence法理学juror陪审员jury陪审团jury charge法官对陪审团的指令jury pool待选陪审员库jury selection挑选陪审员jury trial陪审团制justice公正，大法官justice of the peace治安法官justifiable homicide正当杀人juvenile court未成年人法庭juvenile delinquency未成年人违法行为ＫKey man assurance关键人保险Key person insurance关键人保险Kickbacks回扣Kill杀人Killer杀人者Know-how技术秘密，商业秘密Ｌland use law土地使用法last clear chance doctrine最后明显机会法则law 法，法律law firm律师事务所law merchant商业习惯法law of evidence证据法law reform法律改革lawsuit诉讼，官司lawyer律师lawyer in government政府律师；官方律师lawyer in private practice私人开业律师lawyerette律师娘lawman外行人lay witness普通证人；非专家证人lease租赁lease agreement租赁协议legacy遗产legacy tax遗产税legal合法的legal advice法律咨询legal commentary法律评论legal education法律教育legal effect法律教育legal enforcement法律效力legal English法律英语legal family法系legal history 法律史legal instrument 法律文件legal mechanism法律机制legal memorandum 法律备忘录legal methodology 法律方法论legal order 法律秩序legal problem 法律问题legal profession 法律职业legal protection 法律保护legal relationship 法律关系legal representative 法律代表legal safeguard 法律保障（措施）legal system 法律体系；法律制度legal theorist 法学理论家legal writing 法律文书写作legalese 法律涩语legality 法制legislation 立法legislative branch 立法部门legislative history 立法史legislature 立法机关legitimate 合法的levy 征收（税）liability 责任；债务liability insurance 责任保险liberty 自由license plate （车）执照牌license tax 执照税lien 留置（权）life estate 终生财（遗）产life insurance 人寿保险limited partnership 有限合伙liquidated damages 预定违约金liquidity risk 流动资金风险literary property 著作产权litigant 诉讼当事人litigation 诉讼；打官司livestock insurance 家畜保险loan 贷款lord chancellor (英国)大法官loss of rights 丧失权利Jurisprudence，History of Legal Systems and Constitution按照法律规定according to law按照确定的份额分享权力：be entitled to rights in proportion to his proper share of the credit按照确定的份额分担义务：assume obligations in proportion to his proper share of the debt案例教学法case system案例汇编case book；case report；law report柏拉图Plato《保护人权与基本自由公约》（1950）Convention for the Protection of Human Rights and Fundamental Freedoms，1950（罗）被视为be deemed as被宣布为非法be outlawed；be declared illegal比较法comparative law比较法学comparative jurisprudence比较法学派school of comparative jurisprudence比较法制史comparative legal history比较分析法method of comparative analysis比较刑法comparative penal law比较刑法学comparative penal jurisprudence必然因果关系positive causal relationship边缘法学borderline jurisprudence变通办法adaptation；accommodation补充规定supplementary provision补救办法remedial measures不成文法unwritten law不成文宪法unwritten constitution不动产所在地法律law of the place where the real property is situated；lex loci rei immobilisci不可分割的权利impartible right不可抗力force majuere不可侵犯性inviolability不可让与性inalienability不履行法律义务non-performance of obligation不要式行为informal act不要因的法律行为non-causal juristic act不因实效而丧失的权利imprescriptible right不作为abstain from an act；act of omission部门法department law部门规章regulation参照consult参照具体情况in the light of actual conditions参照原文consult the original查士丁尼法典Code Justinian；Codex Justinianus查士丁尼法规汇编Authenticum超出法律范围的outside of law超出法律权限的extralegal超过权限exceed authority；beyond jurisdiction成文法written law成文宪法written constitution冲突法conflict of laws；rules of conflict冲突规则conflict rule；rule of conflict除（本法）另有规定外except for otherwise stipulated （by this law）除外条款provisory clause除外责任条款exclusion clause触犯公共利益encroach on the public interests触犯国际利益go against the state's interests触犯人民利益encroach on the interests of the people；go against the people's interests传统法律观念traditional ideas of law纯粹法学pure theory of law次要法规by law次要规则secondary rule从宽解释原则doctrine of liberal construction从权利accessory right达到法定年龄come of age大法the fundamental law大法官Lord High Chancellor大法官法院Court of Chancery大陆法系Continental Legal System大律师barrister《大明律》Criminal Law of the Ming Dynasty（中）大陪审团grand jury《大清律例》the Criminal Laws of the Qing Dynasty （中）《大宪章》（1215）Great Charter，1215（英）单行法规specific regulations单一法律体系unitary legal system单一制政府unitary government但书proviso当代法学动向current trend of jurisprudence当然解释natural interpretation党纪国法party discipline and the law of the country道德规范norm of morality道德义务moral obligation《德国民法典》German Civil code德拉古Draco地方各级人民代表大会local people's congresses at different levels 地方各级人民法院local people's courts at different levels地方各级人民检察院local people's procuratorates at different levels 地方各级人民政府local people's governments at different levels第二读second reading第三读third reading二元论the dualistic theory二元君主立宪制dual constitutional monarchy system二元论the dualistic theory二元论者dualist二元制bicameral system法的本质the nature of law法的变化changes of law法的定义definition of law法的发展development of law法的分类divisions of law法的概念concepts of law法的规范作用normalized usage of law法的继承succession of law法的精神spirit of law法的可预测性foreseeability of law法的类型types of law法的历史类型的更替the replacement of one historical mode of law by another 法的历史渊源historical origin of law法的连续性continuity of law法的内容contexts of law法的社会作用social usage of law法的生效operation of law法的实现realization of law法的特征character of law法的现象legal phenomenon法的消亡withering away of law法的形式渊源formal source of law法的要素elements of law法的渊源source of law法的职能function of law法的作用role of law法典code；statute book法典编纂codification of codes法定成年人的年龄age of majority；legal age法定程序legal procedure法定处罚statutory penalty法定代理人：agent ad litem法定解释statutory interpretation法定量刑情节legally prescribed circumstances of sentencing 法定年龄legal age；lawful age法定年龄限制 a statutory age limit法定期间prescribed time法定期限legal term法定权利legal right；right entitled by law法定权限limits of power prescribed by law法定人数quorum法定日appointed day法定时间appointed time法定时效statutory prescription法定条件legal condition法定限制statutory restrictions法定效力statutory force法定刑legally-prescribed punishment法定形式legal form法定责任statutory duty法定追溯期time of legal memory法定最高刑maximum statutory penalty；maximum statutory sentence 法官judge法官的自由裁量权judge's power of discretion法官权力范围extent of judge's power法官心证judge's mental impression法官中立原则Nemo debt esse judex in propria causa法规编纂condification of laws and regulations法规的解释interpretation of statutes法规汇编corpus of the laws and regulations《法国民法典》Code Civile de Francais （法）法理jurisprudence；principle of law法理学家jurisprudent法律保护legal protection法律编纂codification法律标准legal standards法律补救legal redress法律部门legal department法律草案draft regulations法律措施legal measures法律大全Corpus legum法律的本土化和改写the localization and adaptiion of laws 法律的本质essence of law法律的地位position of law法律的定义definition of law法律的废止abolishment of law法律的公共秩序论public order theory of law法律的规范性normalization of law法律的继承succession of law法律的理想ideal of law法律的权威authority of law法律的失效lapse of law法律的实施administration of law；law enforcement法律的适用application of law法律的统一unification of law法律的推定presumption of law法律的推理analogy of law法律的完整性integrity of law法律的效力范围force's scale of law法律的效力形式force's form of law法律的修改alteration of law法律的演进evolutin of law法律的原理principle of law法律地位平等equal in legal status法律对人的效力personal act of law编纂法律方法legal methodology法律分类classification of law法律赋予权力authority conferred by law法律改革law reform法律概念legal concept法律根据legal basis法律工作者legal professional法律关系legal relation法律关系的运行process of legal relation法律关系客体object of legal relation法律关系主体subject of legal relation法律规定provisions of law法律规范norm of law法律规范的逻辑结构logical structure of legal rule 法律规则体系system of legal rules法律含义intendment of law法律另有规定：otherwise stipulated by law法律现象legal phenomenon法律研究legal research法律要件legal requirement法律依据legal basis法律意见legal advice法律意见书legal opinion法律意识law-consciousness法律意义legal sense法律用语legal language法律与正义先验论 a prior theory of law and justice法律渊源source of law法律原本注释gloss法律原理legal doctrines法律原则principle of legality法律援助legal aid法律约束legal binding；legal restraint法律责任legal responsibility法律责任的道义基础moral basic of legal obligation法律责任的归结imputaton of legal responsibility法律责任的认定determination of legal responsibility法律责任的执行enforcement of legal responsibility法律责任客体object of legal responsibility法律责任主体subject of legal responsibility法律哲学philosophy of law；philosophie du droit （法）；philosophia juris 法律政策policy of the law法律职业道德legal ethics法律指导legal counsel法律制裁legal sanction法律制度regime of law；legal system法律秩序legal order法律主体资格capacity as a subject of law法律主张proposition of law法律属地原则territoriality of laws法律著述legal literature法律专家legal expert法律专业legal profession法律专著和教科书legal treati法律咨询legal advice法律尊严legal sanctity法盲legal illiterates法权right法社会学sociology of law法系legal system法协会law society法学jurisprudence法学博士doctor of jurisprudence法学导论leading principles of law法学的范畴体系the system of categories of jurisprudence法学的范畴意识the consciousness of category of jurisprudence 法学的基石范畴fundamental categories of jurisprudence法学方法method of jurisprudence法学方法论methodology of jurisprudence法学会law society法学教科书law textbooks。

A model of forum shopping, with special reference to standard setting organizations

A Model of F orum Shopping,with Special Reference to Standard SettingOrganizations∗Josh Lerner†Jean Tirole‡July21,2004AbstractOwners of intellectual property or mere sponsors of an idea(e.g.,authors,se-curity issuers,sponsors of standards)often need to persuade potential buyers oradopters of the worth of their property or idea.To this purpose,they often resortto more or less independent certiﬁers.This paper analyzes the strategic choice ofcertiﬁers in rival and non-rival situations in a three-stage game.First,the owner/sponsor selects among potential certiﬁers.Certiﬁers diﬀer in their degree of sym-pathy towards the owner/sponsor’s interests relative to their concern for qualitydelivered to the users.Second,the certiﬁer studies the oﬀering and renders an opin-ion.The opinion consists of an endorsement(or lack thereof)and,possibly,somefurther demands for changes involving prices or oﬀering characteristics.Third,theﬁnal users adopt or buy as a function of their perceived utility.In this context,the choice of certiﬁer involves a basic trade-oﬀ:trying a tougher certiﬁer reducesthe probability of a positive opinion,but makes the users more likely to adopt theoﬀering or willing to pay more for it in case of a positive opinion by the certiﬁer.The paperﬁrst analyzes the sponsor’s choices of certiﬁer and design,as well as social preferences regarding these choices.More attractive standards lead to morefriendly certiﬁcation and fewer concessions to users.Regulation cannot improveon private choices in case of mildly attractive standards,and partial regulationreduces social welfare in case of attractive standards.Furthermore,the sponsor cancostlessly delegate the design choice to the certiﬁer when she can have her preferredchoice of certiﬁer,but must make more concessions to users than she would wantto if the spectrum of certiﬁers is limited.The paper then extends the basic model to multiple categories of users,to the downstream presence of the sponsor,and to within-user-group network externalities.Finally,it studies strategic forum shopping by sponsors of competing standards.Keywords:forum shopping,certiﬁcation,standards.JEL numbers:D71,D82,L15,O31.∗We are grateful to a number of practitioners for helpful discussions and to Patrick Rey,Mike Roth-schild,and Lucy White for comments.Emmanuel Fahri provided superb research assistance.In partic-ular,he suggested and proved Propositions13and14.We thank Harvard Business School’s Division of Research and the U.S.National Science Foundation forﬁnancial support.All errors are our own.†Harvard University and NBER.‡IDEI and GREMAQ(UMR5604CNRS),Toulouse,CERAS(URA2036CNRS),Paris,and MIT.1IntroductionOwners of tangible or intangible property or mere sponsors of an idea need to persuade potential buyers or adopters of the worth of their property or idea.To this purpose,they often resort to more or less independent certiﬁers.Rather than just publishing works on the web or in non-refereed books,academics typically submit their research to journals, which vary in how demanding their standards are and in their sympathy for various topics. Authors attempt to convince reputable publishing houses to print their work,and search for endorsements from well-regarded peers.Issuers of bonds or stocks are eager to receive certiﬁcation from investment banks,analysts,and rating agencies,which diﬀer in their reputation and independence.Technology sponsors attempt to build standards around their technologies by having them validated by standard setting organizations(SSOs)that range from fully independent to largely captive special interest groups(SIG).This paper is aﬁrst pass at analyzing the strategic choice of certiﬁers in rival and non-rival situations.It employs a three-stage game.First,the owner/sponsor selects among potential certiﬁers.Certiﬁers diﬀer in their degree of sympathy towards the owner /sponsor’s interests relative to their concern for quality delivered to the users.Second, the certiﬁer studies the oﬀering and renders an opinion.The opinion consists of an endorsement(or lack thereof)and,possibly,some further demands for price changes or adjustments of the oﬀering characteristics.Third,theﬁnal users adopt or buy as a function of their perceived utility.In this context,the choice of certiﬁer involves a basic trade-oﬀ:trying a tougher certiﬁer reduces the probability of a positive opinion,but makes the users more likely to adopt the oﬀering or willing to pay more for it in case of a positive opinion by the certiﬁer.Because we discuss some case study evidence from standard setting in the next section, we couch the framework as one in which the certiﬁers are SSOs.But as the examples provided above illustrate,the theoretical part of the paper has much broader applicability.The paper is organized as follows.Section2provides some further motivation by dis-1cussing sponsors’choice of SSOs.The theoretical partﬁrst analyzes the sponsor’s choices of certiﬁer and design,as well as social preferences regarding these choices(Sections3and 4).The paper then extends the basic model to multiple categories of users,to downstream presence of the sponsor,and to within-user-group network externalities(Section5).Fi-nally it studies strategic forum shopping by sponsors of competing standards(Section6). Related literaturea)Literature on standardsDespite the copious research on standards,it is striking how little work has addressed the question of how SSOs should be organized or howﬁrms should choose between com-peting SSOs.Many of the papers in the literature focus only on de facto standard setting, where there is no role for a SSO in the model(e.g.,Farrell and Saloner1985).Alterna-tively,a number of works,both in economics and political science,have focused on settings where government bodies have played the key role in adjudicating between the desires of diﬀerent parties about possible standards(e.g.,Farrell and Shapiro1992).The economics literature analyzing SSOs has largely focused on just one role:that of a meeting room,i.e.,a setting where the parties can negotiate.1The other roles played by committees–such as facilitating information sharing,actively promoting design compromises,and certifying new standards–are ignored.And there is no need for more than one SSO in this setting,since the features of the SSO do not matter.Farrell(1996)and Simcoe(2003)model the standard-setting process as a“war of attrition”between two parties with their own proposed standards.As in the rest of the literature,the various participants receive a larger share of the proﬁts if their own standard is selected.Participants have private information about the quality of their proposed standard.These papers show that ultimately,the higher-quality technology will 1For example,in Farrell and Saloner(1988),twoﬁrms can choose between two incompatible technolo-gies.They can do so by repeatedly talking with each other(seen as akin to a SSO),by product market competition(de facto standard setting in the marketplace),or a hybrid between the two approaches.The authors show that the committee process is more likely to arrive at a high-value consensus than product market competition,but that it usually takes longer.The hybrid approach is likely to dominate both of the alternatives.2be selected,but that the delays will be a function of the presence of vested interests. In Simcoe’s model,which incorporates explicit voting by SSO participants,relaxing the hurdle needed to approve a standard will reduce delay,but may also reduce the probability that the best technology is selected.Reducing vested interests(e.g.,by adopting rules that limit the utilization of intellectual property used in standards)will reduce delays.When vested interests are already quite high,or when the dispersion of quality is high enough, decreasing vested interests will boost rather discourage the innovations undertaken by the twoﬁrms.The nature of SSO organizations,and the impact of these structures on the standards selected,has attracted little empirical attention as well.Most of the empirical pieces have been based on individual case studies(e.g.,Sirbu-Zwimpfer1985)or comparisons of a small number of cases(Besen-Johnson1985,Weiss-Sirbu1990).They have largely focused on a question somewhat diﬀerent from the one that we examine,namely the way in which an individual SSO chooses between competing standards that rivalﬁrms are championing.b)Literature onﬁnancial certiﬁcationManyﬁnancing decisions are characterized by insuﬃcient information held by poten-tial investors,that may result in a breakdown of the market.A large literature inﬁnancial economics,beginning with Diamond(1984),has highlighted the importance of intermedi-aries in certifyingﬁrms seeking to raise externalﬁnancing.2Among the institutions whose certiﬁcation role has been highlighted in theoretical and/or empirical studies have been commercial and investment banks,venture capitalists,large-block shareholders,analysts, auditors,and rating agencies.3This literature has largely ignored the strategic choice of 2E.g.,Admati-Pﬂeiderer(1994),Chemmanur-Fulghieri(1994),Lizzeri(1999),and Peyrache-Quesada (2003).3These intermediaries can play this role for three reasons.First,the intermediaries are able to gen-erate intensive knowledge about the issuingﬁrm due to their involvement with theﬁrm.Second,the intermediary must have acquired substantial reputational capital that it risks by certifying theﬁrm.If theﬁrm subsequently proves to have misstated its potential,then the intermediary’s reputation capital may be tarnished.Third,the intermediary may take aﬁnancial stake in theﬁrm.3certiﬁers byﬁrms(often assuming that the intermediary is a monopolist),as well as sev-eral other issues considered in this paper.A notable exception is Morrison-White(2004), in which banks apply to regulators with heterogenous abilities to screen.A successful ap-plication allows banks to raise more deposits,all the more so as the regulator’s screening ability is perceived as high.The focus and analysis in Morrison and White are rather diﬀerent from ours,as their primary interest lies in examining the impact of international ﬁnancial liberalization in allowing banks to beneﬁt from foreign supervision.c)Literature on real authorityThis paper is also related to the literature on real authority within organizations. Using the terminology of Aghion and Tirole(1997),in this paper,the sponsor selects a non-congruent SSO that will have real authority over the users.Although quite diﬀerent in motivation and execution,our work is therefore related to that of Dessein(2002).In his model,a principal delegates formal authority to a supervisor with preferences that are intermediate between hers and the agent’s.This step motivates the agent to exercise initiative,because he knows that the supervisor will listen to him.It is also related to Caillaud and Tirole’s(1999)work on ideological bias.They show that a party with partisan rank-and-ﬁle members is,in the eyes of uninformed voters,a more credible certiﬁer for the strength of the(optimally)centrist platform of its leadership than a party with a centrist rank-and-ﬁle.This relationship implies that partisan parties may defeat centrist ones even in a Downsian world,where the median voter dictates political choices.2An illustration4One way to illustrate these issues is to consider standard-setting organizations.Our interviews suggest two patterns that are consistent with the premises of the theoretical 4This section is based on interviews with SSO participants and corporate managers responsible for standards.4analysis below:•that SSOs diﬀer in terms of the extent to which they are attuned to user’s desires, and in the way sponsors have control over the standard;•that certiﬁcation is a real concern ofﬁrms sponsoring new proposed standards.Theﬁrst point can be illustrated by the fact that aﬁrm seeking to get a technology adopted as a new standard frequently faces a choice of three or four SSOs from which it could seek certiﬁcation.In making a choice between existing SSOs,or between new and existing organizations,the prestige of the body is an important consideration.While for manyﬁrms,the ideal standard is a de facto one,which it or perhaps a special interest group promulgates and everyone else adheres to,in many cases it cannot get a standard established without being approved by a prestigious established SSO.Relatedly,ﬁrms believe that SSOs diﬀer considerably in the extent to which a spon-soringﬁrm can inﬂuence the process.(The key variables include the composition of the membership and the rules employed in reviewing proposed standards.)SSOs also diﬀer in the extent of requirements regarding the disclosure and licensing of intellectual property.5 To illustrate these general points,consider two SSOs with similar mandates.(Even more extreme diﬀerences would have been seen if we compared an SSO and a special interest group.)The Internet Engineering Task Force(IETF)is responsible for engineer-ing and developing protocols for the Internet.It was formally established in1986,but predecessor organizations date back at least as far as the early1970s.The International Telecommunications Union(ITU)has been seeking to ensure the standardization of com-munications since a1865agreement to facilitate the interconnection of national telegraph systems.With a membership encompassing telecommunication policy-makers and regu-lators,network operators,equipment manufacturers,hardware and software developers, 5Firms’preferences diﬀer considerably across technologies.In some cases,they may very strongly feel that it is important that they not commit to licensing their key patents;in other cases,they do not mind making such commitments.5and regional standards-making organizations,today it seeks to develop standards and policies for all aspects of telecommunications.These two groups diﬀer along a number of dimensions.One aspect is the nature of the participants.At the IETF,individual members make decisions.At the ITU,national governments are the key voting bodies;that is,the governments typically have formal or informal bodies that seek to reconcile the divergent views of domesticﬁrms and to form a consensus,and in many cases the largestﬁrms have dominated these advisory bodies.6A second diﬀerence is the degree to which corporations can inﬂuence the process.This reﬂects the way in which the two SSOs are organized,particularly the role that the area directors play.At the ITU,the area director is primarily responsible for the managing the standard-setting process.At the IETF,the area director has responsibility for both the technical quality and process.This often leads to a more activist approach.As a result, eﬀorts by corporations to shape the standard-setting agenda were often less successful. This point can be illustrated by considering the process of initiating new projects at the ITU and IETF.At the ITU,a proposal for a new project is brought to a study group.After reaching a consensus,the work begins while formal approval is solicited.The proposed research agenda is circulated to the membership at large,an advisory group,and the body of chairs of the various working groups.While all parties are free to suggest changes,the study group is relatively free to accept or reject the proposed modiﬁcations.At the IETF, however,the area(an equivalent of a study group)must begin with a written proposal to their area director before initiating a project.The area director will discuss the proposal with his peers,and then commence a formal evaluation procedure that entails holding one or two meetings of prospective contributors.The area director will assess both the number of attendees and the quality of the discussion at the meetings before giving permission 6It should be noted that while in itsﬁrst decades,engineers largely did participate in the IETF as objective individual experts,regardless of their corporate aﬃliations,and the agendas of theseﬁrms and decisions were largely driven by technological considerations,today this has changed somewhat.The much greater stakes associated with the adoption of particular standards(particularly in light of the bleak commercial environment for Internet and communicationsﬁrms)implies that pressure is put on engineers in some cases to conform to corporate priorities during the decision-making process.6whether to proceed with the project or not.While there is an appeal process,the area director’s decision typically is the last word.As a result of the diﬃculty that individual ﬁrms frequently encounter in shaping the IETF agenda,it has been argued that the ITU is a much more sympathetic venue for proposals by large telephone companies.3Forum shopping:basics3.1ModelWe now present a simple model of sponsor’s choice among SSOs.In subsequent sections, we introduce some reﬁnements.Sponsors and users:Consider the sponsor(or group of sponsors)of a potential standard. The standard,if adopted,will yield proﬁtπ>0to the sponsor,and utility U for the users of the standard.For the moment,we distinguish between sponsor and users;later on,the sponsor will also have a downstream presence.Also,users should be understood in a broad sense,and include in particular future innovators building on the technology. Users adopt the standard only if they perceive U to be positive.SSOs:The sponsor chooses an SSO.SSOs are characterized by their user-friendliness,or more generally,by the ease with which a sponsor can get his standard approved by the SSO.A SSO has objective functionU+απ.For analytical convenience,we will assume in much of the paper that there is"free entry in the SSO market":there is a continuum of SSOs indexed byα∈[0,∞).Free entry in the SSO market is a strong assumption,but it allows us to useﬁrst-order conditions to capture our main points in a very simple manner.The parameterα(which is common knowledge for each SSO)measures the conﬂict of interest.It may be very large for a SIG,and very low for an SSO with a user orientation. In general,αreﬂects,among other factors:•the ease with which a yes vote can be obtained:simple majority rule,absence of a7requirement of multiple interoperable implementations,and so forth,•the composition of the board(users versus members of SIG),•whether the users are direct or indirect users(downstreamﬁrms that compete with each other may pass through some of their cost increases–or,in Section4,an increase in the royalty rate–to theﬁnal consumer,and therefore their stake may be smaller than that of users as a whole),•the SSO’s reputational concern vis-à-vis users.Users’utility:Users have utilityU=a+b,where a is common knowledge and serves to calibrate the initial strength of the pro-posed standard.This strength depends on common-knowledge technical merits and on the existence of alternative technologies.In particular,a is smaller in the presence of an alternative technology,since the users’utility must be taken net of the opportunity cost of adopting this particular technology.The parameter b is unknown to both sponsor and users and reﬂects the unobserved quality of the proposed standard for the users:How promising is the technology itself?Is the technology likely to be blocked by(valid)patents?Or,if the technology is composed of multiple pieces of intellectual property owned by several sponsors,how well do those pieces interact with each other to beneﬁt the users?Allowing for some private information about b held by the sponsor would complicate the analysis but not reverse our main conclusions, as discussed below.Note also that SSOs all observe the same b.Thus,the sponsor,if she uses multiple SSOs,will not do so because she wants a second opinion after aﬁrst negative one.7Let F(b)denote the cumulative distribution function.We assume that F has the standard monotone hazard rate property:f/[1−F]is increasing.This property in turn 7Morrison and White(2004)develop a model in which certiﬁers make mistakes and economic agents looking for certiﬁcation may sequentially go down the list of certiﬁers.Meyer and Rothschild(2004) adds incomplete information to the standard matching model,and apply this to sequential acceptation processes.8implies thatm(b)≡E h e b¯¯¯e b≥b igrows with b at a rate lower than1(e.g.,An[1998]).Furthermore:m0(b)≡h f(b)i[m(b)−b].TimingWe consider the following three-stage game:(1)The sponsor chooses an SSO,that isα.(2)The SSO learns b(more generally,it could learn a signal of b),and then chooses whether to recommend the standard.(3)Users decide whether to adopt the standard.We believe these assumptions about timing are plausible.SSOs do indeed frequently involve end users,and consequently can get a sense of a proposed standard’s potential value.Because many technologies are still in their early stages at the time that the standard is endorsed,users frequently defer the decision whether to employ the standard until after it has been endorsed.In this bare-bones version of the model,the SSO plays a pure certiﬁcation role.In practice,besides this central function,SSOs play the auxiliary roles of setting constraints on sponsors(e.g.,disclosure and licensing requirements)and of inducing a convergence of rival sponsors on a unique standard.Such roles,which are discussed in the next sections,are less fundamental in that the sponsor(s),unlike for the certiﬁcation function,can achieve the outcomes by themselves.3.2Equilibrium forum shoppingAt stage(2),the SSO approves the standard when facing signal b if and only if8[a+b]+απ≥0.8We ignore the"babbling equilibria"in which the users never adopt the standard and the SSO approves randomly(this equilibrium exists if a+E[b]<0)or else the SSO always recommends and users adopt regardless of the recommendation(this equilibrium exists if a+E[b]>0).Given this,the continuation equilibrium outcome for a givenαis unique.9A higherαmeans a more likely approval.Users adopt the standard when approved by the SSO if and only if9E[a+b|a+b+απ≥0]≥0,ora+E[b|b≥−(a+απ)]≥0.(1) The left-hand side of inequality(1)decreases withαand increases with a.The sponsor chooses the highest possibleαsubject to the credibility constraint(1). Hence:•If a+E[b]≥0,thenα∗=∞:the technology will be adopted as a de facto standard anyway,and so there is no point risking being turned down by a standard setting organi-zation.•If a+E[b]<0(the interesting case),thena+E[b|b≥−(a+α∗π)]=0ora+m(b∗)=0,whereb∗≡−(a+α∗π).(2) Because the conditional mean m(·)has slope between0and1,equation(2)deﬁnes a single and increasing solutionα∗(a).Note also that the sponsor has no incentive to apply to a more sympathetic SSO (α>α∗)when turned down,as the standard will then not be adopted anyway:a+E[b|−(a+α∗π)>b≥−(a+απ)]<0.9In order to avoid“openness problems,”we will assume that users adopt with probability one if(1) is satisﬁed with equality(this is indeed the only equilibrium possibility).10Proposition1The weaker the proposed standard,the more credible the SSO selected by the sponsor:α∗increases with a.The sponsor’s expected payoﬀis then[1−F(−a−α∗(a)π)]π.In the conversations we had withﬁrms active in the standard-setting process,this proposition was repeatedly corroborated.Our interviewees emphasized that they only selected as strong a SSO as was needed to gain widespread acceptance of the standard.We may compare the allocation resulting from the sponsor’s choice of SSO and that that would obtain under a social planner putting an exogenous relative weight w on the sponsor’s interests relative to the users’.Such a social planner would want adoption whenever b≥b b,where a+b b+wπ=0For attractive standards(α∗(a)>w),the sponsor chooses an SSO that is too friendly from a social viewpoint,and so the social planner would like to impose a less complacent SSO.For less attractive standards(α∗(a)<w),by contrast,the social plannerﬁnds users to be too reluctant to adopt the technology(as they do not internalize the sponsor’s beneﬁt).Yet there is nothing that the social planner can do.An SSO that was more friendly thanα∗(a)would be unable to get users on board by endorsing the standard.Proposition2From the point of view of a social planner putting relative weight w on the sponsor’s interests relative to the users’,the sponsor’s choice of SSO is•too complacent if the technology is very attractive(α∗(a)>w),•constrained optimal if the technology is less attractive(α∗(a)·w).3.3Can the sponsor do better?One may wonder whether the strategy described in Section3.2is overall optimal for the sponsor.We have indeed assumed that the sponsor applies to a single SSO;the sponsor11could apply to multiple SSOs either simultaneously or sequentially.Also,the SSO issues a0/1recommendation;the SSO could convey more information(for example,announce b).It turns out that,in our model,the sponsor cannot deviate from the simple strategy analyzed thus far and obtain a higher payoﬀ:Proposition3The sponsor cannot achieve an expected payoﬀhigher than the one(de-ﬁned in Proposition1)that she obtains by applying to a single SSO with characteristic α∗(a)and issuing a yes/no recommendation.Proof:For any extensive form of the standardization game10and for any b,let X(b)∈[0,1] denote the present discounted probability of adoption by the users when the state of nature is b.11An upper bound on the sponsor’s payoﬀismax {X(·)}E[X(b)π]s.t.E[X(b)(a+b)]≥0and0·X(b)·1for all b.Theﬁrst constraint comes from the users’individual rationality:Were they to expect a negative utility,then they might as well never adopt.Lettingβdenote the shadow price of this constraint,theﬁrst-order condition is:X(b)=1ifπ+β(a+b)>0=0ifπ+β(a+b)<0.10For example,the sponsor could apply to an arbitrary number n0of SSOs of her choice at date0,who would then issue recommendations,resulting in either user adoption,or in non-adoption,in which case at date1the sponsor could apply to an arbitrary number n1of SSOs,and so forth.11For example,ifδis the discount factor and x t(b)denotes the equilibrium unconditional probability that the standard is adopted by the users when b obtains(0·Σ∞0x t(b)·1),thenX(b)=Σ∞0δt x t(b).12The corresponding allocation is implemented through the choice of an SSO with char-acteristic:α=1.¥Our interviewees indeed expressed skepticism about approaching a number of SSOs simultaneously.It is unclear that a second SSO’s endorsement necessarily leads to enough additional certiﬁcation to make it worth the trouble.12Obviously,we do not want to imply that sponsors will always apply to a single SSO. Indeed,the sponsor in this model might want to apply to multiple SSOs if the latter observed only noisy measures of users’utility.Furthermore,Section5.2and Section 6will demonstrate that applying to multiple SSOs may beneﬁt a sponsor when either users are heterogeneous or there is competition from another technology.13Proposition3, however,identiﬁes a robust factor encouraging sponsors to focus on a single SSO:There is no point being more ambitious than needed for adoption,as the stigma from rejection by a tough SSO undoes the beneﬁcial impact of endorsement by a more friendly one.3.4Sponsor has private information about user beneﬁtWe have assumed that the sponsor has no information on the SSO’s future assessment b of user beneﬁt.Suppose by way of contrast that the sponsor receives a signalσabout b with joint distribution H(σ,b)and conditional distribution G(b|σ).Proposition4When the sponsor receives a private signalσregarding the SSO’s assess-ment variable b:(i)it is still an equilibrium for the sponsor to choose SSO with preferenceα∗(a),regard-less of her informationσabout the SSO’s later assessment of the standard’s user beneﬁt; 12Another reason raised by interviewees is related to the concessions that are made by the sponsors: They asserted that it is almost inevitable that multiple standards will emerge:each group is likely to have its own approach,which will lead to them making diﬀerent choices.13A third reason why a sponsor may apply to multiple SSOs is that the latter may make mistakes:see Morrison-White(2004).13。

3. the spirit of law

• • • • • • • • • • • • •
conspire [kən'spaiər] v 阴谋，密谋（against）阴谋，密谋（） conspiracy [kən'spirəsi] n 阴谋 stab [stæb] v 刺杀 odious ['əudiəs] a 讨厌的，可恶的讨厌的， inflame [in'fleim] v 使燃烧，使愤怒使燃烧， regency ['ri:dʒənsi]n摄政期摄政期 exasperate [ig'zɑ:spəreit] əris] n贪婪贪婪 abet [ə'bet] v教唆,唆使;煽动教唆, 教唆唆使; lavish ['læviʃ] a 慷慨的，大方的 ʃ 慷慨的， enjoin [in'dʒɔin] v 命令，禁止（from）命令，禁止（ ɔ ） ordain [ɔ:'dein] v 规定，决定，颁布命令规定，决定， ɔ toll [təul] n （路桥隧道等的）通行费路桥隧道等的）
• 一个叫做贝欧尼乌斯的人是奥赛尔城的伯爵；他派其儿子一个叫做贝欧尼乌斯的人是奥赛尔城的伯爵；穆莫路斯带着银钱给贡特兰，企图继续他的职位；穆莫路斯带着银钱给贡特兰，企图继续他的职位；这个儿子以自己的名义出了钱，并取得了他父亲的位置。子以自己的名义出了钱，并取得了他父亲的位置
• The kings had already begun to spoil their own favours. favours.
1. ----- Changes in the Offices and in the Fiefs
(官职和采地的变更官职和采地的变更) 官职和采地的变更 • in the reign of Clovis’s grandchildren 在克罗维斯的子孙时代 In the reign of 在…朝代，在…统治时期朝代，朝代统治时期 eg. in the reign of Song/ Tang / Qing Dynasty in the reign of Mao Zedong/ Deng Xiaoping

2022年考研考博-考博英语-中国社会科学院考试全真模拟易错、难点剖析AB卷(带答案)试题号：63

2022年考研考博-考博英语-中国社会科学院考试全真模拟易错、难点剖析AB卷（带答案）一.综合题(共15题)1.单选题He doesn’t know much about politics,but he’s always shooting off his mouth about how good he is. He is somewhat of a/an（）.问题1选项A.dogmatistB.adventurerC.braggartD.humbler【答案】C【解析】考查名词辨析。

A选项dogmatist“教条主义者；独断家”；B选项adventurer“冒险家”；C选项braggart“吹牛者；好自夸者”；D选项humbler“谦虚的人”。

句意：他不了解政治，但他总脱口而出夸赞自己有多好。

他多少是个……。

C选项符合题意。

2.单选题The truth about alliances and their merit probably lies somewhere between the travel utopia presented by the players and the evil empires portrayed by their critics.问题1选项A.collaborationB.worthC.triumphD.defect【答案】B【解析】merit“优点，价值，功绩”。

A选项collaboration“合作，勾结”；B选项worth“价值，财产”；C选项triumph“生理，凯旋”；D选项defect“缺点，不足之处”。

B选项与merit“价值”这一意思相近，因此B选项符合题意。

3.单选题Cultural continuities with Africa were not dependent on importation and （）of specific folktales in their pristine form.问题1选项A.perpetuationB.perceptibilityC.perpetrationD.perplexity【答案】A【解析】考查形近名词辨析。

Information Extraction from Single and Multiple Sentences

Information Extraction from Single and Multiple SentencesMark StevensonDepartment of Computer ScienceRegent Court,211Portobello Street,University of SheﬃeldSheﬃeldS14DP,UKmarks@AbstractSome Information Extraction(IE)systemsare limited to extracting events expressedin a single sentence.It is not clear what ef-fect this has on the diﬃculty of the extrac-tion task.This paper addresses the prob-lem by comparing a corpus which has beenannotated using two separate schemes:onewhich lists all events described in the textand another listing only those expressedwithin a single sentence.It was found thatonly40.6%of the events in theﬁrst anno-tation scheme were fully contained in thesecond.1IntroductionInformation Extraction(IE)is the process of identifying speciﬁc pieces of information in text, for example,the movements of company execu-tives or the victims of terrorist attacks.IE is a complex task and a the description of an event may be spread across several sentences or para-graphs of a text.For example,Figure1shows two sentences from a text describing manage-ment succession events(i.e.changes in corpo-rate executive management personnel).It can be seen that the fact that the executives are leaving and the name of the organisation are listed in theﬁrst sentence.However,the names of the executives and their posts are listed in the second sentence although it does not mention the fact that the executives are leaving these posts.The succession events can only be fully understood from a combination of the informa-tion contained in both sentences.Combining the required information across sentences is not a simple task since it is neces-sary to identify phrases which refer to the same entities,“two top executives”and“the execu-tives”in the above example.Additional diﬃ-culties occur because the same entity may be referred to by a diﬀerent linguistic unit.For ex-ample,“International Business Machines Ltd.”may be referred to by an abbreviation(“IBM”),Pace American Group Inc.said it notiﬁed two top executives it intends to dismiss them because an internal investigation found ev-idence of“self-dealing”and“undisclosedﬁ-nancial relationships.”The executives are Don H.Pace,cofounder,president and chief executive oﬃcer;and Greg S.Kaplan,senior vice president and chiefﬁnancial oﬃcer. Figure1:Event descriptions spread across two sentencesnickname(“Big Blue”)or anaphoric expression such as“it”or“the company”.These complica-tions make it diﬃcult to identify the correspon-dences between diﬀerent portions of the text de-scribing an event.Traditionally IE systems have consisted of several components with some being responsi-ble for carrying out the analysis of individual sentences and other modules which combine the events they discover.These systems were of-ten designed for a speciﬁc extraction task and could only be modiﬁed by experts.In an ef-fort to overcome this brittleness machine learn-ing methods have been applied to port sys-tems to new domains and extraction tasks with minimal manual intervention.However,some IE systems using machine learning techniques only extract events which are described within a single sentence,examples include(Soderland, 1999;Chieu and Ng,2002;Zelenko et al.,2003). Presumably an assumption behind these ap-proaches is that many of the events described in the text are expressed within a single sen-tence and there is little to be gained from the extra processing required to combine event de-scriptions.Systems which only attempt to extract events described within a single sentence only report results across those events.But the proportion of events described within a single sentence is not known and this has made it diﬃcult to com-pare the performance of those systems against ones which extract all events from text.This question is addressed here by comparing two versions of the same IE data set,the evaluation corpus used in the Sixth Message Understand-ing Conference(MUC-6)(MUC,1995).The corpus produced for this exercise was annotated with all events in the corpus,including those described across multiple sentences.An inde-pendent annotation of the same texts was car-ried out by Soderland(1999),although he only identiﬁed events which were expressed within a single sentence.Directly comparing these data sets allows us to determine what proportion of all the events in the corpus are described within a single sentence.The remainder of this paper is organised as follows.Section2describes the formats for rep-resenting events used in the MUC and Soder-land data sets.Section3introduces a common representation scheme which allows events to be compared,a method for classifying types of event matches and a procedure for comparing the two data sets.The results and implications of this experiment are presented in Section4. Some related work is discussed in Section5.2Event Scope and Representation The topic of the sixth MUC(MUC-6)was management succession events(Grishman and Sundheim,1996).The MUC-6data has been commonly used to evaluate IE systems.The test corpus consists of100Wall Street Jour-nal documents from the period January1993 to June1994,54of which contained manage-ment succession events(Sundheim,1995).The format used to represent events in the MUC-6 corpus is now described.2.1MUC RepresentationEvents in the MUC-6evaluation data are recorded in a nested template structure.This format is useful for representing complex events which have more than one participant,for ex-ample,when one executive leaves a post to be replaced by another.Figure2is a simpliﬁed event from the the MUC-6evaluation similar to one described by Grishman and Sundheim (1996).This template describes an event in which “John J.Dooner Jr.”becomes chairman of the company“McCann-Erickson”.The MUC tem-plates are too complex to be described fully here but some relevant features can be discussed. Each SUCCESSION EVENT contains the name of <SUCCESSION_EVENT-9402240133-2>:=SUCCESSION_ORG:<ORGANIZATION-9402240133-1>POST:"chairman"IN_AND_OUT:<IN_AND_OUT-9402240133-4>VACANCY_REASON:DEPART_WORKFORCE<IN_AND_OUT-9402240133-4>:=IO_PERSON:<PERSON-9402240133-1>NEW_STATUS:INON_THE_JOB:NOOTHER_ORG:<ORGANIZATION-9402240133-1>REL_OTHER_ORG:SAME_ORG<ORGANIZATION-9402240133-1>:=ORG_NAME:"McCann-Erickson"ORG_ALIAS:"McCann"ORG_TYPE:COMPANY<PERSON-9402240133-1>:=PER_NAME:"John J.Dooner Jr."PER_ALIAS:"John Dooner""Dooner"Figure2:Example Succession event in MUC formatthe POST,organisation(SUCCESSION ORG)and references to at least one IN AND OUT sub-template,each of which records an event in which a person starts or leaves a job.The IN AND OUT sub-template contains details of the PERSON and the NEW STATUSﬁeld which records whether the person is starting a new job or leav-ing an old one.Several of theﬁelds,including POST,PERSON and ORGANIZATION,may contain aliases which are alternative descriptions of theﬁeldﬁller and are listed when the relevant entity was de-scribed in diﬀerent was in the text.For ex-ample,the organisation in the above template has two descriptions:“McCann-Erickson”and “McCann”.It should be noted that the MUC template structure does not link theﬁeldﬁllers onto particular instances in the texts.Conse-quently if the same entity description is used more than once then there is no simple way of identifying which instance corresponds to the event description.The MUC templates were manuallyﬁlled by annotators who read the texts and identiﬁed the management succession events they contained. The MUC organisers provided strict guidelines about what constituted a succession event and how the templates should beﬁlled which the an-notators sometimes found diﬃcult to interpret (Sundheim,1995).Interannotator agreementwas measured on30texts which were examined by two annotators.It was found to be83%when one annotator’s templates were assumed to be correct and compared with the other.2.2Soderland’s Representation Soderland(1999)describes a supervised learn-ing system called WHISK which learned IE rules from text with associated templates. WHISK was evaluated on the same texts from the MUC-6data but the nested template struc-ture proved too complex for the system to learn. Consequently Soderland produced his own sim-pler structure to represent events which he de-scribed as“case frames”.This representation could only be used to annotate events described within a single sentence and this reduced the complexity of the IE rules which had to be learned.The succession event from the sentence “Daniel Glass was named president and chief executive oﬃcer of EMI Records Group,a unit of London’s Thorn EMI PLC.”would be represented as follows:1@@TAGS Succession{PersonIn DANIEL GLASS}{Post PRESIDENT AND CHIEF EXECUTIVE OFFICER} {Org EMI RECORDS GROUP}Events in this format consist of up to four components:PersonIn,PersonOut,Post and Org.An event may contain all four components although none are compulsory.The minimum possible set of components which can form an event are(1)PersonIn,(2)PersonOut or(3) both Post and Org.Therefore a sentence must contain a certain amount of information to be listed as an event in this data set:the name of an organisation and post participating in a management succession event or the name of a person changing position and the direction of that change.Soderland created this data from the MUC-6evaluation texts without using any of the existing annotations.The texts wereﬁrst pre-processing using the University of Mas-sachusetts BADGER syntactic analyser(Fisher et al.,1995)to identify syntactic clauses and the named entities relevant to the management suc-cession task:people,posts and organisations. Each sentence containing relevant entities was examined and succession events manually iden-tiﬁed.1The representation has been simpliﬁed slightly for clarity.This format is more practical for machine learning research since the entities which par-ticipate in the event are marked directly in the text.The learning task is simpliﬁed by the fact that the information which describes the event is contained within a single sentence and so the feature space used by a learning algorithm can be safely limited to items within that context. 3Event Comparison3.1Common Representation andTransformationThere are advantages and disadvantages to the event representation schemes used by MUC and Soderland.The MUC templates encode more information about the events than Soderland’s representation but the nested template struc-ture can make them diﬃcult to interpret man-ually.In order to allow comparison between events each data set was transformed into a com-mon format which contains the information stored in both representations.In this format each event is represented as a single database record with fourﬁelds:type,person,post and organisation.The typeﬁeld can take the values person in,person out or,when the di-rection of the succession event is not known, person move.The remainingﬁelds take the person,position and organisation names from the text.Theseﬁelds may contain alternative values which are separated by a vertical bar (“|”).MUC events can be translated into this format in a straightforward way since each IN AND OUT sub-template corresponds to a sin-gle event in the common representation.The MUC representation is more detailed than the one used by Soderland and so some in-formation is discarded from the MUC tem-plates.For example,the VACANCY REASON ﬁled which lists the reason for the manage-ment succession event is not transfered to the common format.The event listed in Figure2would be represented as follows: type(person in)person(‘John J.Dooner Jr.’|‘John Dooner’|‘Dooner’)org(‘McCann-Erickson’|‘McCann’)post(chairman)Alternativeﬁllers for the person and org ﬁelds are listed here and these correspond to the PER NAME,PER ALIAS,ORG NAME and ORG ALIASﬁelds in the MUC template.The Soderland succession event shown in Section 2.2would be represented as follows in the common format.type(person in)person(‘Daniel Glass’)post(‘president’)org(‘EMI Records Group’)type(person in)person(‘Daniel Glass’)post(‘chief executive officer’)org(‘EMI Records Group’)In order to carry out this transformation an event has to be generated for each PersonIn and PersonOut mentioned in the Soderland event. Soderland’s format also lists conjunctions of post names as a single slotﬁller(“president and chief executive oﬃcer”in this example).These are treated as separate events in the MUC for-mat.Consequently they are split into the sepa-rate post names and an event generated for each in the common representation.It is possible for a Soderland event to consist of only a Post and Org slot(i.e.there is nei-ther a PersonIn or PersonOut slot).In these cases an underspeciﬁed type,person move,is used and no personﬁeld listed.Unlike MUC templates Soderland’s format does not contain alternative names forﬁeldﬁllers and so these never occur when an event in Soderland’s for-mat is translated into the common format.3.2MatchingThe MUC and Soderland data sets can be com-pared to determine how many of the events in the former are also contained in the latter. This provides an indication of the proportion of events in the MUC-6domain which are express-ible within a single sentence.Matches between Soderland and MUC events can be classiﬁed as full,partial or nomatch.Each of these possi-bilities may be described as follows:Full A pair of events can only be fully match-ing if they contain the same set ofﬁelds.In addition there must be a commonﬁller for eachﬁeld.The following pair of events are an example of two which fully match.type(person in)person(‘R.Wayne Diesel’|‘Diesel’)org(‘Mechanical Technology Inc.’|‘Mechanical Technology’)post(‘chief executive officer’)type(person in)person(‘R.Wayne Diesel’)org(‘Mechanical Technology’)post(‘chief executive officer’)Partial A partial match occurs when one event contains a proper subset of theﬁelds of an-other event.Eachﬁeld shared by the two events must also share at least oneﬁller.The following event would partially match either of the above events;the orgﬁeld is absent therefore the matches would not be full.type(person in)person(‘R.Wayne Diesel’)post(‘chief executive officer’)Nomatch A pair of events do not match if the conditions for a full or partial match are not met.This can occur if correspondingﬁelds do not share aﬁller or if the set ofﬁelds in the two events are not equivalent or one the subset of the other.Matching between the two sets of events is carried out by going through each MUC event and comparing it with each Soderland event for the same document.The MUC event isﬁrst compared with each of the Soderland events to check whether there are any equal matches.If one is found a note is made and the matching process moves onto the next event in the MUC set.If an equal match is not found the MUC event is again compared with the same set of Soderland events to see whether there are any partial matches.We allow more than one Soder-land event to partially match a MUC event so when one is found the matching process con-tinues through the remainder of the Soderland events to check for further partial matches.4Results4.1Event level analysisAfter transforming each data set into the com-mon format it was found that there were276 events listed in the MUC data and248in the Soderland set.Table1shows the number of matches for each data set following the match-ing process described in Section3.2.The countsunder the“MUC data”and“Soderland data”headings list the number of events which fall into each category for the MUC and Soderland data sets respectively along with corresponding percentages of that data set.It can be seen that 112(40.6%)of the MUC events are fully cov-ered by the second data set,and108(39.1%) partially covered.Match MUC data Soderland data Type Count%Count%Full11240.6%11245.2% Partial10839.1%11847.6% Nomatch5620.3%187.3% Total276248Table1:Counts of matches between MUC and Soderland data.Table1shows that there are108events in the MUC data set which partially match with the Soderland data but that118events in the Soderland data set record partial matches with the MUC data.This occurs because the match-ing process allows more than one Soderland event to be partially matched onto a single MUC event.Further analysis showed that the diﬀerence was caused by MUC events which were partially matched by two events in the Soderland data set.In each case one event contained details of the move type,person in-volved and post title and another contained the same information without the post title.This is caused by the style in which the newswire sto-ries which make up the MUC corpus are writ-ten where the same event may be mentioned in more than one sentence but without the same level of detail.For example,one text contains the sentence“Mr.Diller,50years old,succeeds Joseph M.Segel,who has been named to the post of chairman emeritus.”which is later fol-lowed by“At that time,it was announced that Diller was in talks with the company on becom-ing its chairman and chief executive upon Mr. Segel’s scheduled retirement this month.”Table1also shows that there are56events in the MUC data which fall into the nomatch cat-egory.Each of these corresponds to an event in one data set with no corresponding event in the other.The majority of the unmatched MUC events were expressed in such a way that there was no corresponding event listed in the Soder-land data.The events shown in Figure1are examples of this.As mentioned in Section2.2, a sentence must contain a minimum amount of information to be marked as an event in Soder-land’s data set,either name of an organisation and post or the name of a person changing po-sition and whether they are entering or leaving. In Figure1theﬁrst sentence lists the organisa-tion and the fact that executives were leaving. The second sentence lists the names of the exec-utives and their positions.Neither of these sen-tences contains enough information to be listed as an event under Soderland’s representation, consequently the MUC events generated from these sentences fall into the nomatch category. It was found that there were eighteen events in the Soderland data set which were not in-cluded in the MUC version.This is unexpected since the events in the Soderland corpus should be a subset of those in the MUC corpus.Anal-ysis showed that half of these corresponded to spurious events in the Soderland set which could not be matched onto events in the text.Many of these were caused by problems with the BAD-GER syntactic analyser(Fisher et al.,1995) used to pre-process the texts before manual analysis stage in which the events were identi-ﬁed.Mistakes in this pre-processing sometimes caused the texts to read as though the sentence contained an event when it did not.We exam-ined the MUC texts themselves to determine whether there was an event rather than relying on the pre-processed output.Of the remaining nine events it was found that the majority(eight)of these corresponded to events in the text which were not listed in the MUC data set.These were not identi-ﬁed as events in the MUC data because of the the strict guidelines,for example that historical events and non-permanent management moves should not be annotated.Examples of these event types include“...Jan Carlzon,who left last year after his plan for a merger with three other European airlines failed.”and“Charles T.Young,chiefﬁnancial oﬃcer,stepped down voluntarily on a‘temporary basis pending con-clusion’of the investigation.”The analysis also identiﬁed one event in the Soderland data which appeared to correspond to an event in the text but was not listed in the MUC scenario tem-plate for that document.It could be argued that there nine events should be added to the set of MUC events and treated as fully matches. However,the MUC corpus is commonly used as a gold standard in IE evaluation and it was de-cided not to alter it.Analysis indicated that one of these nine events would have been a fullmatch and eight partial matches.It is worth commenting that the analysis car-ried out here found errors in both data sets. There appeared to be more of these in the Soderland data but this may be because the event structures are much easier to interpret and so errors can be more readily identiﬁed.It is also diﬃcult to interpret the MUC guidelines in some cases and it sometimes necessary to make a judgement over how they apply to a particular event.4.2Event Field AnalysisA more detailed analysis can be carried out examining the matches between each of the fourﬁelds in the event representation individu-ally.There are1,094ﬁelds in the MUC data. Although there are276events in that data set seven of them do not mention a post and three omit the organisation name.(Organisa-tion names are omitted from the template when the text mentions an organisation description rather than its name.)Table4.2lists the number of matches for each of the four eventﬁelds across the two data sets. Each of the pairs of numbers in the main body of the table refers to the number of matching in-stances of the relevantﬁeld and the total num-ber of instances in the MUC data.The column headed“Full match”lists the MUC events which were fully matched against the Soderland data and,as would be expected, allﬁelds are matched.The column marked “Partial match”lists the MUC events which are matched onto Soderlandﬁelds via partially matching events.The column headed“No-match”lists the eventﬁelds for the56MUC events which are not represented at all in the Soderland data.Of the total1,094eventﬁelds in the MUC data727,66.5%,can be found in the Soderland data.The rightmost column lists the percent-ages of eachﬁeld for which there was a match. The counts for the type and personﬁelds are the same since the type and personﬁelds are com-bined in Soderland’s event representation and hence can only occur together.Theseﬁgures also show that there is a wide variation between the proportion of matches for the diﬀerentﬁelds with76.8%of the person and typeﬁelds be-ing matched but only43.2%of the organisation ﬁeld.This diﬀerence betweenﬁelds can be ex-plained by looking at the style in which the texts forming the MUC evaluation corpus are writ-ten.It is very common for a text to introduce a management succession event near the start of the newswire story and this event almost in-variably contains all four eventﬁelds.For ex-ample,one story starts with the following sen-tence:“Washington Post Co.said Katharine Graham stepped down after20years as chair-man,and will be succeeded by her son,Don-ald E.Graham,the company’s chief executive oﬃcer.”Later in the story further succession events may be mentioned but many of these use an anaphoric expression(e.g.“the company”) rather than explicitly mention the name of the organisation in the event.For example,this sen-tence appears later in the same story:“Alan G. Spoon,42,will succeed Mr.Graham as presi-dent of the company.”Other stories again may only mention the name of the person in the suc-cession event.For example,“Mr.Jones is suc-ceeded by Mr.Green”and this explains why some of the organisationﬁelds are also absent from the partially matched events.4.3DiscussionFrom some perspectives it is diﬃcult to see why there is such a diﬀerence between the amount of events which are listed when the entire text is viewed compared with considering single sen-tences.After all a text comprises of an ordered list of sentences and all of the information the text contains must be in these.Although,as we have seen,it is possible for individual sentences to contain information which is diﬃcult to con-nect with the rest of the event description when a sentence is considered in isolation.The results presented here are,to some ex-tent,dependent on the choices made when rep-resenting events in the two data sets.The events listed in Soderland’s data require a min-imal amount of information to be contained within a sentence for it to be marked as con-taining information about a management suc-cession event.Although it is diﬃcult to see how any less information could be viewed as repre-senting even part of a management succession event.5Related WorkHuttunen et al.(2002)found that there is varia-tion between the complexity of IE tasks depend-ing upon how the event descriptions are spread through the text and the ways in which they are encoded linguistically.The analysis presented here is consistent with theirﬁnding as it hasFull match Partial match Nomatch TOTAL% Type112/112100/1080/56212/27676.8% Person112/112100/1080/56212/27676.8% Org112/1126/1080/53118/27343.2% Post111/11174/1080/50185/26968.8% Total447/447280/4320/215727/109466.5% Table2:Matches between MUC and Soderland data atﬁeld levelbeen observed that the MUC texts are often written in such as way that the name of the organisation in the event is in a diﬀerent part of the text to the rest of the organisation de-scription and the entire event can only be con-structed by resolving anaphoric expressions in the text.The choice over which information about events should be extracted could have an eﬀect on the diﬃculty of the IE task.6ConclusionsIt seems that the majority of events are not fully described within a single sentence,at least for one of the most commonly used IE evaluation sets.Only around40%of events in the original MUC data set were fully expressed within the Soderland data set.It was also found that there is a wide variation between diﬀerent eventﬁelds and some information may be more diﬃcult to extract from text when the possibility of events being described across multiple sentences is not considered.This observation should be borne in mind when deciding which approach to use for a particular IE task and should be used to put the results reported for IE systems which extract from a single sentence into context. AcknowledgementsI am grateful to Stephen Soderland for allowing access to his version of the MUC-6corpus and advice on its construction.Robert Gaizauskas and Beth Sundheim also provided advice on the data used in the MUC evaluation.Mark Hep-ple provided valuable comments on early drafts of this paper.I am also grateful to an anony-mous reviewer who provided several useful sug-gestions.ReferencesH.Chieu and H.Ng.2002.A Maximum Entroy Approach to Information Extraction from Semi-structured and Free Text.In Pro-ceedings of the Eighteenth International Con-ference on Artiﬁcial Intelligence(AAAI-02), pages768–791,Edmonton,Canada.D.Fisher,S.Soderland,J.McCarthy,F.Feng, and W.Lehnert.1995.Description of the UMass system as used for MUC-6.In Pro-ceedings of the Sixth Message Understand-ing Conference(MUC-6),pages221–236,San Francisco,CA.R.Grishman and B.Sundheim.1996.Mes-sage understanding conference-6:A brief history.In Proceedings of the16th Interna-tional Conference on Computational Linguis-tics(COLING-96),pages466–470,Copen-hagen,Denmark.S.Huttunen,R.Yangarber,and R.Grishman. plexity of Event Structures in IE Scenarios.In Proceedings of the19th Interna-tional Conference on Computational Linguis-tics(COLING-2002),pages376–382,Taipei, Taiwan.MUC.1995.Proceedings of the Sixth Mes-sage Understanding Conference(MUC-6), San Mateo,CA.Morgan Kaufmann.S.Soderland.1999.Learning Information Ex-traction Rules for Semi-structured and free text.Machine Learning,31(1-3):233–272. B.Sundheim.1995.Overview of results of the MUC-6evaluation.In Proceedings of the Sixth Message Understanding Conference (MUC-6),pages13–31,Columbia,MA.D.Zelenko,C.Aone,and A.Richardella.2003. Kernel methods for relation extraction.Jour-nal of Machine Learning Research,3:1083–1106.。

2022年gre考试考生如何把握答题节奏

gre考试考生如何把握答题节奏如何提升考试分数?你首先需要把握的是gre考试答题节奏，下面我就和大家共享gre考试考生如何把握答题节奏，来观赏一下吧。

gre考试考生如何把握答题节奏?gre考试的时间安排和答题节奏始终是同学们关注的话题。

虽然每个人都知道时间和节奏的重要性，但在现实生活中，很难避开忽视细节。

gre考试的用途究竟是什么是许多同学都在问的一个问题，对于有些人来说是特别重要的，gre规章在复习时应当被理解，这一环节往往被忽视。

GRE考试时间如何安排和掌控，始终以来都是GRE考生绕不过去的一道坎。

哪怕是再简洁的题目，一旦扯上限时完成难度就会大增。

因此，掌握好考试时间和答题节奏就成了考生的必修课。

那么，考生怎样才能保证在长达4个小时的GRE考试中始终把握好gre考试答题节奏呢?对于同学来说，有三个gre考试答题技巧要点需要多加留意。

1. 学会区分时间消耗问题GRE考试最大的干扰之一就是耗时的问题。

GRE考试有各种各样的问题和不同程度的难度。

有些问题好像很简洁，但往往需要候选人花许多时间来解决。

这些是考生在考试中需要特殊留意的最耗时的问题，由于它们往往会打乱考试的节奏。

由于并不难所以不情愿放弃，这些问题往往是利用考生的心态来度过你珍贵的时间。

因此，我们必需学会识别这些问题并准时实行措施。

gre考试介绍,新gre考试策略无论是投入时间，还是查找一种快速的解决方法，或者只是猜想答案然后跳过它，都要确保你能尽快做出打算。

准时的决策可以关心考生摆脱因时间消耗问题造成的影响和损失。

没有练习就不要去考场答题节奏不同于学问点，有些考生可能上考场前某个题型或者详细学问点还没彻底把握，但考试中恰好没遇到因此侥幸没有受到影响。

但答题节奏PACE却不存在这种侥幸。

没练好PACE直接上考场后果往往很严峻。

难题花时间太多还没做好，简洁题目时间又不够用做不完，最终得分惨不忍睹。

许多第一次接触GRE考试的考生，只是复习了各类学问点，做了一些练习，在没有参与过水平测试实际体验过GRE时间压力的状况下，就直接上了考场。

Comparison of extraction versus nonextraction orthodontic treatment outcomes for borderline

ORIGINAL ARTICLEComparison of extraction versus nonextraction orthodontic treatment outcomes for borderline Chinese patientsTian-Min Xu,a Yan Liu,b Min-Zhi Yang,b and Wei Huang bBeijing,ChinaIntroduction:The purpose of this study was to compare orthodontic treatment outcomes in Chinese patientswith borderline problems treated with and without extractions.Methods:Records of39borderline patients treated at the Faculty Clinic of the Peking University Orthodontic Department were evaluated retrospectivelyby5associate professors.Sixteen patients had been treated without extractions,and23had4ﬁrst or second premolars extracted.Each judge evaluated the posttreatment records independently for tooth alignment,overbite,overjet,midline symmetry,lateral occlusion,and facial proﬁle,and rated them on a scalefrom1to5.Results:The only statistically signiﬁcant difference between the extraction and nonextraction groups was for facial proﬁle,with the judges preferring the extraction proﬁles.Fifteen soft-tissue cephalo-metric variables were measured to determine the source of the difference,and6showed statisticallysigniﬁcant differences.When proﬁle changes from pretreatment to posttreatment were examined,signiﬁcant differences in treatment-associated changes between extraction and nonextraction groups were all relatedto the lower lip and chin.Conclusions:In this sample of Chinese borderline orthodontic patients,Chinese clinicians had a statistically signiﬁcant preference for the facial proﬁles of the extraction patients,but no statistically signiﬁcant preferences for tooth alignment,overbite,overjet,midline symmetry,or posterior occlusion.Extraction treatment increases the inclination of the chin and reduces protrusion of the lower lip compared with nonextraction treatment,and this might explain the difference.(Am J Orthod Dentofacial Orthop2006;129:672-7)T he decision to extract teeth as part of orthodon-tic treatment is governed mainly by concernsabout facial appearance.Some investigators have reported a remarkable consistency in the criteria for facial attractiveness across cultures and ethnic groups,1-7 but others have reached different conclu-sions.8-12 The purpose of this study was to assess preferences of Chinese orthodontic specialists for treat-ment outcomes related to tooth alignment,overbite, overjet,midline symmetry,lateral occlusion,and facial proﬁle in a sample of growing Chinese children who receivedﬁxed-appliance extraction or nonextraction orthodontic treatment.Soft-tissue cephalometric mea-surements were made to investigate the reasons for the proﬁle differences between the extraction and the nonextraction patients.MATERIAL AND METHODSThe study was conducted in the Orthodontic Depart-ment,Peking University School of Stomatology.The sample comprised39patients classiﬁed as“borderline”by the following method:5associate professors evaluated the pretreatment records(study casts,facial photographs, lateral cephalograms,and panoramic x-rays)of patients who had started treatment2years ing a method modiﬁed from that of Baumrind et al,13 the 5 judges independently classiﬁed each subject in1of3 categories:extraction,nonextraction,or borderline.If it was unanimous(5to0)or a clear majority(4to1)vote of the judges for either the extraction or the nonextraction category,the subject was assigned to that category.If the judges were unanimous or had a clear majority for the borderline classiﬁcation,or if more than3judges failed to agree on extraction or nonextraction,those subjects were assigned to the borderline group.In this way,39patients were chosen as our borderline sample.The distributions by extraction or nonextraction assignment,age,sex,and Angle classiﬁcation are shown in Table I.From the Department of Orthodontics,Peking University School of Stomatol-ogy,Peking University,Beijing,China.a Professor.b Assistant professor.Supported by the Ministry of Health PR China.Reprint requests to:Dr Tian-Min Xu,Department of Orthodontics,Peking University School of Stomatology,Peking University,22#ZhongGuanCun South Street,HaiDian District,Beijing100081,China;e-mail,tmxu@ or tmxu2004@Submitted,December2004;revised and accepted,December2004.0889-5406/$32.00Copyright©2006by the American Association of Orthodontists.doi:10.1016/j.ajodo.2005.12.007672The judges’decisions were based solely on the examination of pretreatment records.The treating orth-odontists were also full-time faculty members in the department.Each orthodontist was blinded with respect to the judges’decisions,and each patient was treated with fullﬁxed appliances solely on the basis of the orthodontist’s treatment decision.The sample included 12boys and27girls.Their mean age at the beginning of treatment was12.4Ϯ1.4years.The sample included 18subjects with Angle Class I malocclusions,19Class II subjects,and2Class III subjects.After treatment,it was found that the orthodontists had treated16patients without extractions,14with extraction of the4ﬁrst premolars,and9with extraction of the4second premolars.After treatment,5faculty judges evaluated the posttreatment records of each patient independently according to an analog scale from1to5for tooth alignment,overbite and overjet,midline symmetry, lateral occlusion,and facial proﬁle.Three of the5 judges had been members of the classifying panel;the other2were full-time associate professors but had not previously participated in the study.The scores from different groups were compared with the rank sum test.To explain proﬁle preferences between the extrac-tion and nonextraction groups,soft-tissue cephalomet-ric measurements were made for33patients(6were excluded because the quality of the soft-tissue images was poor).The distributions by extraction or nonex-traction assignment,age,sex,and Angle classiﬁcation for these 33 patients are shown in Table II.Two third-year residents located the landmarks on the screen,and the average values were obtained by the computer for cephalometric analysis.Independent sam-ple t tests were used for comparison between extraction and nonextraction groups,and between the2extraction patterns.RESULTSThe average treatment period,and the scoring of treatment results on tooth alignment,overbite and overjet,midline symmetry,lateral occlusion,and facial proﬁle, of the 39 subjects are summarized in Table III. Comparison of the extraction and nonextraction groups showed that the extraction group had a higher score than the nonextraction group only on facial proﬁle (Table III). The rank sum test among the 4 ﬁrst-premolar(4PM1)extraction group,the4second-pre-Table I.Demographic distribution of39borderline subjectsSex(n)Angle classiﬁcation(n)Age(y)at start Male Female Total Class I Class II Class III Total Mean SD Nonextraction6101611501612.1 1.09 Extraction*6172371422312.3 1.65 Total1227391819239*Extraction category includes4PM1patients(nϭ14)and4PM2patients(nϭ9).Table II.Demographic distribution of33borderline subjectsSex(n)Angle classiﬁcation(n)Age(y)at start Male Female Class I Class II Class III Total Mean SD Extraction51661322112.47 1.66 4PM1494811312.46 1.71 4PM217251812.50 1.69 Nonextraction667501212.08 1.08Table III.Average scoring of treatment results evaluated by5specialists and treatment periods of each groupnAlignment(meanϮSD)OB and OJ(meanϮSD)Midline(meanϮSD)Occlusion(meanϮSD)Proﬁle(meanϮSD)Treatment time(meanϮSD)(mo)Nonextraction16 4.28Ϯ0.2 4.53Ϯ0.3 4.55Ϯ0.3 4.18Ϯ0.3 4.18Ϯ0.322.1Ϯ8.3 Extraction23 4.17Ϯ0.2 4.40Ϯ0.4 4.60Ϯ0.3 4.28Ϯ0.2 4.47Ϯ0.324.7Ϯ8.2 4PM114 4.22Ϯ0.2 4.31Ϯ0.5 4.63Ϯ0.3 4.31Ϯ0.2 4.47Ϯ0.325.2Ϯ7.7 4PM29 4.08Ϯ0.3 4.54Ϯ0.3 4.56Ϯ0.3 4.24Ϯ0.3 4.48Ϯ0.223.9Ϯ9.3 OB,Overbite;OJ,overjet.Volume129,Number5molar(4PM2)extraction group,and the nonextraction group showed no statistically signiﬁcant differences except for facial proﬁle between the4PM1extraction group and the nonextraction group,and between the 4PM2extraction group and the nonextraction group. The4PM2extraction group received the highest score, and the nonextraction group received the lowest score.The soft-tissue cephalometric measurements are shown in Table IV. (The results for 4PM1 and 4PM2 extraction treatments are reported separately in Tables V, VI,and VII,which are available online at www.mosby. com/AJODO.)DISCUSSIONThe concept of the borderline patient has been widely discussed in orthodontics,but few attempts have been made to deﬁne the term exactly. Carey,14 who was probably among theﬁrst to use the term in the litera-ture,used it in a somewhat different sense from that in which it is used today.He suggested that patients with arch-length discrepancies of less than2.5mm should be treated by nonextraction,whereas those with discrep-ancies of more than5mm should be treated by extraction of the4ﬁrst premolars.Intermediate,or borderline, patients with2.5to5mm of discrepancy were to be treated by extraction of the4second premolars.With improved understanding,orthodontists now believe that the decision of whether to extract is multifactorial,de-pending also on such additional factors as incisor protru-sion,arch width,curve of Spee,growth pattern and potential,facial proﬁle,stability,and the clinician’s edu-cation or training.Also,in modern usage,borderline now refers to patients for whom it is uncertain as to whether extractions should be performed.In this context, Luppanapornlarp and Johnston15 and Paquette et al16 used discriminant-function analysis to identify various borderline cephalometric measure-ments for which some clinicians would treat nonextrac-tion whereas others would treat with premolar extrac-tions.With a somewhat similar line of reasoning, Baumrind et al13 pointed out that any clinician planning treatment for a patient must ultimately decide either to extract or not to extract.Hence,they believed that borderline appropriately refers to patients for whom some skilled clinicians,each given all appropriate diagnostic information,would be likely to make oppo-site decisions.To our knowledge,our study is theﬁrst in which reviewing clinicians have been asked to identify borderline patients.It provides a new method for comparing clinical controversies.When the charts of the patients who had completed active treatment were checked1year after the study began,it was found that,among the39patients,16had received nonextraction treatment and23had received extraction treatment.Among the extraction patients,14 hadﬁrst premolars extracted and9had second premo-lars extracted, an approach that, in Carey’s sense,14 could be considered a compromise between extraction and nonextraction.The comparisons among these3 groups are the focus of this study.Clinician’s preference for treatment resultsA successful treatment is difﬁcult to quantify.Ceph-alometric analysis is used to determine abnormal valuesTable parison of extraction group and nonextraction groupPretreatment Posttreatment Changes Extraction Nonextraction P Extraction Nonextraction P Extraction Nonextraction P Ns-Sn-Pos165.7Ϯ7.2165.4Ϯ6.1.914164.6Ϯ4.4163.8Ϯ4.5.594Ϫ1.1Ϯ4.9Ϫ1.6Ϯ4.4.728 Cm-Sn-UL97.8Ϯ12.395.7Ϯ12.3.646105.2Ϯ9.9100.4Ϯ10.3.1977.4Ϯ11.4 4.7Ϯ9.1.484 LL-Bs-Pos134.2Ϯ9.0128.2Ϯ16.2.182134.7Ϯ9.0136.2Ϯ11.5.6790.5Ϯ7.38.0Ϯ11.3.028* AsUL-FH61.1Ϯ7.958.1Ϯ7.6.29667.0Ϯ6.161.3Ϯ8.8.037* 5.9Ϯ7.4 3.2Ϯ8.5.346 BsLL-FH38.3Ϯ8.738.4Ϯ12.3.97944.7Ϯ8.144.6Ϯ8.7.963 6.4Ϯ5.2 6.2Ϯ11.7.937 PosBs-FH84.1Ϯ9.390.2Ϯ7.2.06290.0Ϯ9.488.4Ϯ4.4.575 5.9Ϯ6.7Ϫ1.8Ϯ5.5.002†UL-EPϪ0.4Ϯ2.1 1.0Ϯ3.8.183Ϫ1.6Ϯ1.50.1Ϯ2.1.014*Ϫ1.2Ϯ1.7Ϫ0.9Ϯ2.4.755 LL-EP 2.7Ϯ2.5 2.0Ϯ3.1.5090.2Ϯ1.8 1.6Ϯ1.1.023*Ϫ2.4Ϯ1.9-0.4Ϯ3.4.031* UL-SnPos7.0Ϯ2.18.2Ϯ3.1.220 5.8Ϯ1.57.5Ϯ1.9.008†Ϫ1.3Ϯ1.8Ϫ0.7Ϯ1.8.380LL-SnPos 6.7Ϯ2.8 6.0Ϯ2.7.474 4.6Ϯ2.1 6.1Ϯ1.1.021*Ϫ2.1Ϯ2.00.2Ϯ2.6.007†Bs-LiPos 4.7Ϯ0.9 5.4Ϯ1.7.139 5.0Ϯ0.8 5.1Ϯ1.3.8670.4Ϯ0.7Ϫ0.3Ϯ1.0.044* As-E-lineϪ6.4Ϯ2.3Ϫ5.1Ϯ2.8.177Ϫ7.2Ϯ1.7Ϫ6.5Ϯ2.1.280Ϫ0.8Ϯ2.2Ϫ1.3Ϯ3.0.570 H-angle16.8Ϯ3.919.0Ϯ6.0.21815.4Ϯ3.118.3Ϯ3.5.021*Ϫ1.5Ϯ2.3Ϫ0.7Ϯ3.9.506 Bs-E-lineϪ3.2Ϯ1.8Ϫ4.3Ϯ1.8.092Ϫ4.9Ϯ1.5Ϫ4.2Ϯ1.3.179Ϫ1.7Ϯ1.50.1Ϯ1.0.001†UL-Ns-LL 4.1Ϯ1.4 5.2Ϯ2.5.111 4.0Ϯ1.3 4.3Ϯ1.8.510Ϫ0.1Ϯ1.6Ϫ0.9Ϯ1.2.165 *pϽ0.05.†pϽ0.01.May2006from means,but mean value does not mean good result.“Aesthetics is certainly personal and interpretive,and the norms are based on a combination of the author’s concept of aesthetics and the sample that the author uses to establish his norms,which in turn is biased by his view of aesthetics.”17 Some indexes, such as the peer assessment rating (PAR)and the index of orthodontic treatment need (IOTN),can be used to evaluate dentition and occlusion,but each was designed for a special purpose.The IOTN is used to prioritize orthodontic treatment.18 The weighting system of the PAR is also affected by the panel of orthodontists.19-21 However, patients and doctors have standards in their minds about whether a treatment is good and which treatment result is better than the others,without measuring anything.This study is based on clinicians’mental standards to evaluate the treatment results of a borderline sample of Chinese patients to determine what orthodontists prefer for face,teeth,and occlusion achieved by extraction or nonextraction treat-ment,respectively.The results showed that,on average,5experienced orthodontists preferred the extraction pa-tients’facial proﬁles over the proﬁles of the nonextraction patients.Tooth alignment,overbite and overjet,midline symmetry,lateral occlusion,and treatment period were almost the same for the patients treated by either extrac-tion or nonextraction in our sample.That encouraged us todetermine what made the difference in the facial proﬁles of the extraction or nonextraction borderline patients.Because hard-tissue relationships are invisible to clini-cians,this study focused on soft-tissue analysis.Cephalometric comparison of pretreatment soft-tissue proﬁlesFacial prognathism is an important factor in planning for extraction or nonextraction.Generally,protrusive lips dictate extraction.But for borderline patients,it is not clear.Table IV shows that none of the pretreatment measurements showed statistically signiﬁcant differences between the extraction and nonextraction groups,imply-ing that the soft-tissue proﬁle does not determine extrac-tion or nonextraction in borderline patients.However,the Ns-Sn-Pos angle (Fig 1) of the 4PM1 extraction group was much smaller than that of the 4PM2extraction group at the P ϭ.014level,indicating that the 4PM1and 4PM2extraction groups should not be combined into 1group.When comparing each group with the nonextraction group, the PosBs/FH angle (Fig 2) of the 4PM1 extraction group was much smaller than in the nonextraction group,but none of the 15soft-tissue measurements showed a statistically signiﬁcant difference between the 4PM2ex-traction group and the nonextraction group.It canbeFig 1.Ns-Sn-Pos angle was smaller in 4PM1group than in 4PM2group in borderlinepatients.Fig 2.PosBs/FH angle was smaller in 4PM1group than in nonextraction group in borderline patients.Extraction treatment can increase this angle.Volume 129,Number 5concluded from the pretreatment soft-tissue comparison that the soft-tissue morphology of the4PM2extraction group was similar to that of the nonextraction group, whereas the4PM1extraction group was different from the other groups.Cephalometric comparison of posttreatmentsoft-tissue proﬁleAlthough the pretreatment soft-tissue morphologies were almost the same between the extraction and nonex-traction groups for borderline patients,6of15posttreat-ment soft-tissue measurements had statistically signiﬁcant differences(Table IV),all related to lip protrusion that was reduced more in the extraction group,as expected. The interestingﬁnding is that when splitting the extraction group into4PM1and4PM2groups and comparing each with the nonextraction group for facial proﬁles,the situ-ation is just the opposite to that of pretreatment.None of the15soft-tissue measurements had statistically signiﬁ-cant differences between the4PM1extraction group and the nonextraction group;however,6of the15measure-ments had statistically signiﬁcant differences between the 4PM2extraction group and the nonextraction group.This implies that the choice between the two extraction patterns may have made the difference in the posttreatment soft-tissue proﬁles.Because all6signiﬁcant measurementsreﬂect less lip protrusion,we tentatively believe that the reason for the4PM2extraction group’s high score(Table III)is that Chinese orthodontists prefer less protrusive lips. Differences in facial attractiveness preferences of clini-cians of various ethnicities and cultural backgrounds are now under investigation between2orthodontic departments—Peking University in China and Univer-sity of the Paciﬁc in the United States. Cephalometric comparison of soft-tissueproﬁle changesOrthodontists care more about treatment changes,the difference in the direction of the changes,and the amount of change caused by extraction and nonextraction.Table IV shows that signiﬁcant differences of treatment-associ-ated changes between these2methods are all related to lower lips and chin.Because there was no signiﬁcant difference between the changes of the2extraction pat-terns,we paid more attention to the changes between 4PM1extraction and nonextraction,and between4PM2 extraction and nonextraction.The results show that,with either4PM1or4PM2extraction,the more sensitive items related to soft-tissue changes are chin inclination to FH plane (PosBs-FH; Fig 2), lower lip prognathism (LL-SnPos; Fig 3), and soft-tissue B-point to esthetic plane (Bs-EP; Fig 4). Extraction treatment increases chin incli-nation but decreases lower lip and soft-tissue B-point prognathism.The interestingﬁnding is that,although orthodontists care more about upper-lip prognathism, extraction treatment did not change it signiﬁcantly more than nonextraction treatment did.The probable reasons are(1)the average pretreatment prognathism for the extraction and nonextraction groups of borderline patients are similar,and,because are usually not very bad at the beginning,orthodontists would not change them much; and(2)orthodontists might have“ideal”or“standard”upper lip positions in their minds,so that they move the molars distally for nonextraction patients or mesially for extraction patients after they set the goals for upper-lip position.That makes the signiﬁcant difference between the changes of extraction and nonextraction treatment limited to the lower-lip and the chin areas;orthodontists pay less attention to these in their treatment plans,al-though the changes affect their subjective evaluations,as shown in this study.CONCLUSIONSTreatment of borderline patients,whether by extrac-tion or nonextraction,achieved generally similar results for tooth alignment,overbite and overjet,midline symme-try,and lateral occlusion as judged by Chinese clinicians in this Chinese sample.In the group of borderline subjects,extraction of either 4ﬁrst premolars or4second premolars resulted infacial Fig3.LL-SnPos.Extraction treatment makes lower lip prognathism decrease more than nonextraction treatment.May2006proﬁles that were preferred by a group of Chinese orth-odontists,compared with nonextraction treatment.The probable reason is that Chinese clinicians prefer less protrusive facial proﬁles.In the group of borderline subjects,the pretreatment soft-tissue morphology of the 4PM2patients was similar to that of the nonextraction group;the soft-tissue morphol-ogy of the 4PM1group was different from the other 2groups.The main differences between changes caused by extraction or nonextraction treatment are in the lower-lip and chin areas;these might affect clinicians’preferences in facial proﬁles.SUPPLEMENTARY DATASupplementary data associated with this article can be found, in the online version, at doi:10.1016/j.ajodo.2005.12.015.REFERENCES1.Owens EG,Goodacre CJ,Loh PL,Hanke G,Okamura M,Jo KH,et al.A multicenter interracial study of facial appearance.Part 1:a comparison of extraoral parameters.Int J Prosthodont 2002;15:273-82.2.Hall D,Taylor RW,Jacobson A,Sadowsky PL,Bartolucci A.The perception of optimal proﬁle in African Americans versus white Americans as assessed by orthodontists and the lay public.Am J Orthod Dentofacial Orthop 2000;118:514-25.3.Farrow AL,Zarrinnia K,Azizi K.Bimaxillary protrusion in black Americans—an esthetic evaluation and the treatment consider-ations.Am J Orthod Dentofacial Orthop 1993;104:240-50.4.Martin JG.Racial ethnocentrism and judgment of beauty.J Soc Psychol 1964;63:59-63.5.Udry JR.Structural correlates of feminine beauty preferences in Britain and the United States:a comparison [abstract].Sociol Soc Res 1965;49:330.6.Ford CS,Prothro ET,Child IL.Some transcultural comparisons of esthetic judgment.J Soc Psychol 1966;68:19-26.7.Child IL,Iwao S.Personality and esthetic sensitivity:extension of ﬁndings to younger age and different culture.J Pers Soc Psychol 1968;8:308-12.8.Sutter RE Jr,Turley PK.Soft tissue evaluation of contemporary Caucasian and African American female facial proﬁles.Angle Orthod 1998;68:487-96.9.Miyajima K,McNamara JA Jr,Kimura T,Murata S,Iizuka T.Craniofacial structure of Japanese and European-American adults with normal occlusions and well-balanced faces.Am J Orthod Dentofacial Orthop 1996;110:431-8.10.Lew KK,Ho KK,Keng SB,Ho KH.Soft-tissue cephalometricnorms in Chinese adults with esthetic facial proﬁles.J Oral Maxillofac Surg 1992;50:1184-90.11.Hashim HA,AlBarakati SF.Cephalometric soft tissue proﬁleanalysis between two different ethnic groups:a comparative study.J Contemp Dent Pract 2003;4:60-73.12.Sim RS,Smith JD,Chan parison of the aesthetic facialproportions of southern Chinese and white women.Arch Facial Plast Surg 2000;2:113-20.13.Baumrind S,Korn EL,Boyd RL,Maxwell R.The decision toextract:part 1—interclinician agreement.Am J Orthod Dentofa-cial Orthop 1996;109:297-309.14.Carey CW.Diagnosis and case analysis in orthodontics.Am JOrthod 1951;38:149-61.15.Luppanapornlarp S,Johnston LE Jr.The effects of premolarextraction:a long-term comparison of outcomes in “clear-cut”extraction and nonextraction Class II patients.Angle Orthod 1993;63:257-72.16.Paquette DE,Beattie JR,Johnston LE Jr.A long-term compar-ison of nonextraction and premolar extraction edgewise therapy in “borderline”Class II patients.Am J Orthod Dentofacial Orthop 1992;102:1-14.17.Bramante MA.Controversies in orthodontics.Dent Clin NorthAm 1990;34:91-102.18.Brook PH,Shaw WC.The development of an index for orth-odontic treatment priority.Eur J Orthod 1989;11:309-32.19.Richmond S,Shaw WC,O’Brien KD,Buchanan IB,Jones R,StephensCD,et al.The development of the PAR index (peer assessment rating):reliability and validity.Eur J Orthod 1992;14:125-39.20.DeGuzman L,Bahiraei D,Vig KWL,Vig PS,Weyant RJ,O’Brien K.The validation of the peer assessment rating index for malocclusion severity and treatment difﬁculty.Am J Orthod Dentofacial Orthop 1995;107:172-6.21.Hamdan AM,Rock WP.An appraisal of the peer assessmentrating (PAR)index and a suggested new weighting system.Eur J Orthod1999;21:181-92.Fig 4.Bs-EP.Extraction treatment makes soft-tissue B-point prognathism decrease compared with nonex-traction.Volume 129,Number 5。

#x #

Abstract We consider uniqueness theorems in classical analysis having the form (+) ∀u ∈ U, v1 , v2 ∈ Vu G(u, v1 ) = 0 = G(u, v2 ) → v1 = v2 , where U, V are complete separable metric spaces, Vu is compact in V and G : U × V → IR is a constructive function. If (+) is proved by arithmetical means from analytical assumptions (++) ∀x ∈ X ∃y ∈ Yx ∀z ∈ Z F (x, y, z ) = 0 only (where X, Y, Z are complete separable metric spaces, Yx ⊂ Y is compact and F : X × Y × Z → IR constructive), then we can extract from the proof of (++) → (+) an eﬀective modulus of uniqueness, i.e. (+ + +) ∀u ∈ U, v1 , v2 ∈ Vu , k ∈ IN |G(u, v1 )|, |G(u, v2 )| ≤ 2−Φuk → dV (v1 , v2 ) ≤ 2−k . Such a modulus Φ can e.g. be used to give a ﬁnite algorithm which computes the (uniquely determined) zero of G(u, ·) on Vu with prescribed precision if it exists classically. The extraction of Φ uses a proof–theoretic combination of functional interpretation and pointwise majorization. If the proof of (++) → (+) uses only simple instances of induction, then Φ is a simple mathematical operation (on a convenient standard representation of X , e.g. on f together with a modulus of uniform continuity for X = C [0, 1]). Various uniqueness theorems in best approximation theory have the form (+) and are proved using only analytical tools of the form (++). We analyse the most common proof of uniqueness for the best Chebycheﬀ approximation of f ∈ C [0, 1] by polynomials of degree ≤ n given by de La Vall´ ee Poussin and obtain explicit moduli of uniqueness and uniform constants of strong unicity. In a subsequent paper two further proofs of this uniqueness will be analysed yielding better estimates (due to the fact that mainly (++)–lemmas are used) which allow us to improve results obtained prior by D. Bridges signiﬁcantly.

TransverseSpinPh...

Transverse Spin Physics:Recent DevelopmentsFeng Yuan1,2∗1-Nuclear Science Division,Lawrence Berkeley National Laboratory,Berkeley,CA94720,USA 2-RIKEN BNL Research Center,Brookhaven National Laboratory,Upton,NY11973,USATransverse-spin physics has been very active and rapidly developing in the last fewyears.In this talk,I will brieﬂy summarize recent theoretical developments,focusingon the associated QCD dynamics in transverse spin physics.There have been strong experimental interests on transverse spin physics around the world,from the deep inelastic scattering experiments such as the HERMES collaboration at DESY,SMC at CERN,and Hall A and CLAS at JLab,the proton-proton collider experiment from RHIC at Brookhaven,and the very relevant e+e−annihilation experiment from BELLE at KEK.One of the major goals in transverse spin physics is to study the quark transversity distribution,the last unknown leading-twist quark distribution in nucleon.As discussed by several talks in this conference,we can study the quark transversity distributions from many processes[1,2,3,4,5],such as the double transverse spin asymmetry in Drell-Yan lepton pair production in pp collision,single hadron and two hadron production in semi-inclusive deep inelastic scattering,and other processes.We are now starting to have aﬁrst glimpse about the quark transversity distribution from the experiments(see from example[5]).Besides the quark transversity distribution,the transverse spin physics also opened a new window to explore the partonic structure of nucleon,the so-called transverse momen-tum dependent(TMD)parton distributions[4].TMD parton distribution is an exten-sion to the usual Feynman parton distributions.These distributions allow us to study the three-dimension picture of partons inside the nucleon,and they are also closely related to the generalized parton distributions[6]and the parton orbital angular momenta.Es-pecially,the single transverse spin asymmetry(SSA)phenomena in high energy hadronic processes have attracted many theoretical and experimental investigations.The SSA is deﬁned as the asymmetry when one of the hadrons’transverse spin isﬂipped,A N∼(dσ(S⊥)−dσ(−S⊥))/(dσ(S⊥)−dσ(−S⊥)).It has been a great theoretical challenge in the understanding of these phenomena.This is because the leading partonic contribution to the SSA vanish in the leading order,whereas the experimental observation show that these SSAs are in tens of percentage in the forward scattering of the polarized nucleon.Recent theoretical developments have made great progress in the exploration of the underlying physics for the single spin phenomena.It is impossible to cover all these exciting physics in this short talk.Rather,I would like to focus on one important subject,i.e.,the nontrivial QCD dynamics associated with transverse spin physics:the QCD factorization, and the universality of the parton distributions and fragmentation functions.Among those TMD parton distributions and fragmentation functions,two functions have been mostly discussed:the Sivers quark distribution and the Collins fragmentation func-tion.The Sivers quark distribution represents a distribution of unpolarized quarks in a ∗This work was supported in part by the U.S.Department of Energy under contract DE-AC02-05CH11231.We are grateful to RIKEN,Brookhaven National Laboratory and the U.S.Department of Energy(contract number DE-AC02-98CH10886)for providing the facilities essential for the completion of this work.transversely polarized nucleon,through a correlation between the quark’s transverse mo-mentum and the nucleon polarization vector.The Collins function represents a correlation between the transverse spin of the fragmenting quark and the transverse momentum of the hadron relative to the “jet axis”in the fragmentation process.Although they both belong to the so-called “naive-time-reversal-odd”functions,they do have diﬀerent universality prop-erties.For the quark Sivers function,because of the initial/ﬁnal state interaction diﬀerence,they diﬀer by signs for the SIDIS and Drell-Yan processes [7,8,9,10].On the other hand,there have been several studies showing that the Collins function is universal between diﬀer-ent processes,primarily in the SIDIS and e +e −annihilation [11,12,13,14],and recently in pp collisions [15].In the following,I will take the example of the Collins contribution to the azimuthal asymmetric distribution of hadrons inside a high energy jet in the transversely polarized pp collision to demonstrate this universality property,p (P A ,S ⊥)+p (P B )→jet (P J )+X →H (P h )+X ,(1)where a transversely polarized proton with momentum P A scatters on another proton with momentum P B ,and produces a jet with momentum P J .The three momenta of P A ,P B and P J form the so-called reaction plane.Inside the produced jet,the hadrons are distributed around the jet axis,where we deﬁne transverse momentum P hT relative to the jet axis.The correlation between P hT and the polarization vector S ⊥introduces the Collins contribution to the single spin asymmetry in this process.Figure 1:Gluon exchange diagrams contributions to the Collins asymmetry in pp collisions.The short bars indicate the pole contributions to the phase needed for a non-vanishing SSA.The additional two cuts in (d)cancel out each other.We need to generate a phasefrom the scattering amplitudes tohave a non-vanishing SSA.If thephase comes from the vertex asso-ciated with the fragmenting quarkand the ﬁnal state hadron,or from the dressed quark propa-gator,it is easy to argue the universality of the Collins func-tion between this process and theSIDIS/e +e −process,because theyare the same.The main issueof the universality discussion con-cerns the extra gluon exchangecontribution between the specta-tor of the fragmentation process and hard partonic part.In Fig.2,we have shown all these inter-actions for a particular partonic channel qq →qq contribution,in-cluding the gluon attachments to the incident quarks (a,c),and ﬁnal state balancing quark (d)and theinternal gluon propagator (b).The contributing phases of the diagrams in Fig.2come from the cuts through the internal propagators in the partonic scattering amplitudes.In Fig.2,we labeled these cut-poles by short bars in the diagrams.From the calculations,we will ﬁnd that all these poles come from a cut through the exchanged gluon and the fragmenting quarkin each diagram,and all other contributions either vanish or cancel out each other.For ex-ample,in Fig.2(d),we show two additional cuts,which contribute however opposite to each other and cancel out completely.Therefore,by using the Ward identity at this particular order,theﬁnal results for all these diagrams will sum up together into a factorized form, where the cross section is written as the hard partonic cross section for q(S⊥)q →q(s⊥)q subprocess multiplied by a Collins fragmentation function.The exchanged gluon in Fig.2 is now attaching to a gauge link from the fragmentation function deﬁnition.Similar calcu-lations can be performed for the other two processes SIDIS and e+e−annihilation,and the same Collins function will be observed.This argument can also be extended to two-gluon exchange diagrams[15].The key steps in the above derivation are the eikonal approximation and the Ward iden-tity.The eikonal approximation is valid when we calculate the leading power contributions in the limit of P hT P J.The Ward identity ensure that when we sum up the diagrams with all possible gluon attachments we shall get the eikonal propagator from the gauge link in the deﬁnition of the fragmentation function.The most important point to apply the Ward identity in the above analysis is that the eikonal propagator does not contribute to the phase needed to generate a nonzero SSA.This observation is very diﬀerent from the SSAs associated with the parton distributions, where the eikonal propagators from the gauge link in the parton distribution deﬁnition play very important role[4,7,8,9,10,16].It is the pole of these eikonal propagators that contribute to the phase needed for a nonzero SSA associated with the naive-time-reversal-odd parton distributions,which also predicts a sign diﬀerence for the quark Sivers function between the SIDIS and Drell-Yan processes.More complicated results have been found for the SSAs in the hadronic dijet-correlation[17,18],where a normal TMD factorization breaks down[19].The reason is that the eikonal propagators from the initial andﬁnal state interactions in dijet-correlation process do contribute poles in the cross section[18,19]. Because of this,the Ward identity is not applicable,and the standard TMD factorization breaks down,although a modiﬁed factorization may be valid if we modify the deﬁnition of the TMD parton distributions to take into account all the initial andﬁnal state interaction eﬀects[17].In particular,there is a sign change between the SSAs in SIDIS and Drell-Yan pro-cesses[7,8],Sivers SSA|DY=−Sivers SSA|DIS.(2) This nontrivial result of the opposite signs between the above two processes will still hold when gluon radiation contributions are taken into account,where the large transverse mo-mentum Sivers function is generated from the twist-three quark-gluon correlation func-tion[20,21].It is of crucial to test this nontrivial QCD predictions by comparing the SSAs in these two processes.The Sivers single spin asymmetry in SIDIS process has been observed by the HERMES collaboration,and the planned Drell-Yan measurement at RHIC and other facility will test this prediction.Another interesting probe for the initial/ﬁnal state interaction eﬀects is the SSA in heavy quark and antiquark production in hadronic process.Because the heavy quark and antiquark can be detected by their decay products,their SSAs can be measured separately.The heavy quark and antiquark produced in short distance partonic processes will experience diﬀerent ﬁnal state interactions with the nucleon spectator due to their diﬀerent color charges,and therefore the SSAs for heavy quark and antiquark will be diﬀerent.Detailed calculationsshow that the diﬀerence could be as large as a factor of3if the quark-antiquark channel contribution dominates[22].In summary,the universality of the parton distribution and fragmentation functions are very diﬀerent in the single transverse spin asymmetry.These properties are still under theoretical and experimental investigations.These important physics,together with other exciting features have shown that the transverse spin physics is playing a very important role in the strong interaction physics for hadronic spin physics.We will learn more about QCD dynamics and nucleon structure from these studies.References[1]K.Tanaka,these proceedings.[2]G.Goldstein,these proceedings.[3]M.Radici,these proceedings.[4]P.Mulders,these proceedings.[5] A.Prokudin,these proceedings.[6]T.Teckentrup,these proceedings.[7]S.J.Brodsky,D.S.Hwang and I.Schmidt,Phys.Lett.B530,99(2002);Nucl.Phys.B642,344(2002).[8]J.C.Collins,Phys.Lett.B536,43(2002).[9]X.Ji and F.Yuan,Phys.Lett.B543,66(2002);A.V.Belitsky,X.Ji and F.Yuan,Nucl.Phys.B656,165(2003).[10] D.Boer,P.J.Mulders and F.Pijlman,Nucl.Phys.B667,201(2003).[11] A.Metz,Phys.Lett.B549,139(2002).[12]J.C.Collins and A.Metz,Phys.Rev.Lett.93,252001(2004).[13]L.P.Gamberg,A.Mukherjee and P.J.Mulders,Phys.Rev.D77,114026(2008).[14]L.Gamberg,these proceedings.[15] F.Yuan,Phys.Rev.Lett.100,032003(2008);Phys.Rev.D77,074019(2008).[16] C.Pisano,these proceedings.[17] C.J.Bomhof,P.J.Mulders and F.Pijlman,Phys.Lett.B596,277(2004);Eur.Phys.J.C47,147(2006);JHEP0702,029(2007);A.Bacchetta,C.J.Bomhof,P.J.Mulders and F.Pijlman,Phys.Rev.D72,034030(2005);C.J.Bomhof and P.J.Mulders,arXiv:0709.1390[hep-ph].[18]J.W.Qiu,W.Vogelsang and F.Yuan,Phys.Lett.B650,373(2007);Phys.Rev.D76,074029(2007);W.Vogelsang and F.Yuan,Phys.Rev.D76,094013(2007).[19]J.Collins and J.W.Qiu,Phys.Rev.D75,114014(2007);J.Collins,arXiv:0708.4410[hep-ph].[20]X.Ji,J.W.Qiu,W.Vogelsang and F.Yuan,Phys.Rev.Lett.97,082002(2006);Phys.Rev.D73,094017(2006);Phys.Lett.B638,178(2006).[21] A.Bacchetta,these proceedings.[22] F.Yuan and J.Zhou,arXiv:0806.1932[hep-ph].。

被害人参加国际刑事法院诉讼的申请及其审查

分庭对申请的审查和处理。
一被害人填写并提交申请表
根据《规则》第８９条的规定，国际刑事法院采取被害人申请参加诉讼的制度。简言之，被
害人必须通过书记官处提出参加的申请，获得相关分庭的准许后方能参加。申请参加的具体程序
为：被害人向书记官长提交申请书，书记官长收到申请后，将该申请书转交给相关分庭，同时给
ＩＣＣ，ＳｉｔｕａｔｉｏｎｉｎＵｇａｎｄａ， “Ｄｅｃｉｓｉｏｎｏｎｖｉｃｔｉｍｓａｐｐｌｉｃａｔｉｏｎｓｆｏｒｐａｒｔｉｃｉｐａｔｉｏｎａ／００１０／０６，ａ／００６４／０６ｔｏａ／００７０／０６，ａ／００８１／０６，
ａ／００８２／０６，ａ／００８４／０６ｔｏａ／００８９／０６，ａ／００９１／０６ｔｏａ／００９７／０６，ａ／００９９／０６，ａ／０１００／０６，ａ／０１０２／０６ｔｏａ／０１０４／０６，ａ／０１１１／
０６，ａ／０１１３／０６ｔｏａ／０１１７／０６，ａ／０１２０／０６，ａ／０１２１／０６ａｎｄａ／０１２３／０６ｔｏａ／０１２７／０６”，１４Ｍａｒｃｈ２００８，ｐａｒａｓ４－６
ＩＣＣ，ＰｒｏｓｅｃｕｔｏｒｖＬｕｂａｎｇａ，ＩＣＣ⁃０１／０４⁃０１／０６⁃６０１⁃ｔＥＮ，６Ｏｃｔｏｂｅｒ２００６，ｐ８
ａｎｄｔｈｅＯｆｆｉｃｅｏｆＰｕｂｌｉｃＣｏｕｎｓｅｌｆｏｒｔｈｅＤｅｆｅｎｃｅａｇａｉｎｓｔＰｒｅ－ＴｒｉａｌＣｈａｍｂｅｒＩｓＤｅｃｉｓｉｏｎｏｆ６Ｄｅｃｅｍｂｅｒ２００７” ，１８Ｊｕｎｅ２００８，

双重任务-4：一款具有集成陷阱和积分泵的蒸汽陷阱产品名称和型号说明书

ApplicationWhen there is modulating control on heat exchange equipment there is a possibility that the system will stall (no longer be able to drain condensate). If only a steam trap is used in this case condensate could flood the heatexchange equipment causing corrosion, water hammer, and poor temperature control. The Double Duty™ - 4 has a steam trap with an integral pump to prevent the system from stalling. If the condensate floods the body of theDouble Duty™ - 4 and reaches its upper trip point high pressure steam will enter the body and push the condensate out. This prevents condensate from accumulating in the heat exchange equipment.Suggested Accessories• Stainless steel discharge check valve • Gauge glass assembly for pump • Gauge glass assembly for receiver • Pressure gauge assembly pump body • Pressure gauge assembly receiver• Pressure gauge assembly motive steam• Pressure gauge assembly heat exchange equipment • ReceiverFeatures1.The trap has an integral pump to prevent flooding of the heat exchange equipment. It uses steam motive with no electricity or special mechanical seals required.2.The majority of parts are attached to the cap which can be removed from the body without taking it out of the condensate line.This bulletin should be used by experienced personnel as a guide to the installation and maintenance of the Armstrong DD4 or DD4 package.Selection or installation of equipment should always be accompanied by competent technical assistance. We encourage you to contact Armstrong or its local representative if further information is required.2OperationOperating as a trap (system pressure greater than back pressure)As the condensate flows through the inlet check valve (5), the float (P)(7) becomes buoyant and rises with the fluid level. The upward movement of the float causes trap valve (P)(3) to open. If the system pressure is greater than the back pressure the condensate will flow through the steam trap valve into the condensate return.Operating as a pump (system pressure less than or equal to back pressure)If the system pressure is less than the back pressure liquid floods the body. When the condensate reaches theupper trip point of the mechanism the motive inlet valve (6) opens and the vent valve closes. The open motive valve allows the motive fluid to enter and pressurize the body. The pressure inside the body shuts the inlet check valve and when it is greater than the back pressure pushes the water through the discharge check valve into thecondensate return line. The float lowers with the water level and when it reaches the lower trip point the motive inletvalve closes and the vent valve opens. This relieves the pressure in the body and allows it to fill again.InstallationInstructions1.Before installing make sure the piping is clean and free of debris. When installing take care to not allow pipe tapeor similar items to enter the product.* Debris can affect proper operation and performance2.Check the condensate inlet, condensate outlet, motive inlet, and vent outlet ports before connecting piping.3.The DD4 must be installed with the vent vertical and the condensate inlet and outlet horizontal.* The product will not function properly if not installed in the correct orientation4.Connect pipes securely5.When connecting pipes unions should be used close to the DD4 connections. This reduces the amount of timeneeded for maintenance and repair.6.Avoid water hammer. If water hammer is experienced if could injure personnel or damage the equipment.7.Do not disassemble product. If the product is disassembled the function or performance of the unit could becompromised.8.Attach strainer with blow down valve on motive steam inlet.9.Attach check valve on condensate discharge.3Height required for disassemblySpace for maintenanceOperating proceduresCaution1.Make sure all connections are secure before opening valves2.Open valves slowly to reduce the chance of water hammerStart-up1.Open isolation valve(s) in condensate discharge.2.Open isolation valve in equalizing line.3.Open motive isolation valve. Confirm that the steam does not flow into the pump body or equalizing line bychecking pressure gauges.4.Open the isolation valve on the thermostatic air vent.5.Open the isolation valve on the condensate inlet.6.The start-up is complete if the Double Duty™ - 4 Four performs trap operation or pump operation and isconfirmed by use of the gauge glasses and pressure gauges.Maintenance and InspectionMost failures occur because of debris in the piping.Caution1.Before starting any maintenance make sure the Double Duty™ - 4 Four is completely isolated from the system2.Make sure the system is at atmospheric pressurePeriodic inspection (once a year)1.Close all isolation valves2.remove plug from top of unit and flow water into this connection3.Confirm a clicking noise when the mechanism trips4.Remove plug from the bottom of unit to drain the water out of the body5.Confirm clicking noise when mechanism trips*if mechanism does not trip replace mechanism and float6.Disassemble motive strainer and check visually*if strainer is clogged it should be cleaned or replaced45Trouble shootingBody (1)Valve seat (4)Check valve seat (6)Valve (P) (3)Float (P) (7)Hexagon nut (18)Bolt (10) A set of inlet valves (6) Inlet valve seat gasket (17)Vent valve seat (15)Vent valve seat gasket (16)Gasket (9)Cover (2)Bolt (11)Name plate (14)Strainer (8)Strainer gasket(20)Strainer cap (19)Plug (12)Plug (13)Vent valve section ofvalve (P)Valve section ofvalve (P)Check valve (5)6Disassembly and Assembly Procedure Caution and WarningBefore disassembly or inspection, release internal pressure of the product, pipes, and devices completely and cool down the product. Do not touch the product with bare hands when it is still hot.*You may get burned or injured due to remaining pressure.1.Internal condensate flows out during disassembly.*Without a container for the removal of draining condensate, peripheral devices might get dirty.2.Check that there are no flaws, dents or stains on the seat suction such as the valve seat. If any stains are found clean them.If flaws or dents are found, replace parts.*Flaws, dents, or stains might result in malfunction.3.Assemble the parts securely. Tighten the bolts evenly in the diagonal order.*Improper assembly or uneven tightening of bolts might result in malfunction or e regular parts for repair of products. Never modify the products.*If the product is modified, you might get burned or injured due to product damange, steam, condensate or abnormal operation.5.Replace the gasket with a new one.*The gasket is a replaceable item. If it is reused, leakage might occur.Disassembly procedure (see Figure 11)Tools Required• Spanner (13mm, 17mm, 24mm)• Adjustable end wrench (width = 0-25mm)• Closed wrench (19mm, 27mm)• Hexagon socket wrench (width across flat: 5mm)• Ratchet handle (used with hexagon socket wrench)Step 1:Remove strainer cap (19) using a closed wrench (width across flat: 27mm). Next remove the strainer (8) and strainer gasket (20).Step 2:Attach the hexagon wrench to the ratched handle. Remove the bolt (11). Move up and remove the cover (2) andgasket (9) from the body (1).7Step 3:Fix the float arm section of valve (P) (3) using the adjustable end wrench. Set the spanner (width across flat 17 mm)at the hexagon section of the float (P) and remove the float (P) (7). The hexagon nut (18) is located at the float arm section. The hexagon nut is necessary for the float (P) assembly.Step 4:Remove two bolts (10) attached to the cover using a spanner (width across flat 13mm) and remove the valve (P) (3).Step 5:Remove a set of the inlet valve (6) using the closed wrench (width across flat 19 mm) and remove the inlet valve seat gasket (17).Step 6:Remove the vent valve seat (15) using a spanner (width across flat 24mm).Remove the vent valve seat gasket (16).Float Arm SectionAdjustable End WrenchSpannerStep 7:Remove the check valve (5) from the body (1) manually.Assembly procedure (see Figure 11)Tools Required• Torque wrench: Contents (size nominal, etc.)• Spanner-type torque wrench (spanner width across flat 17mm - for items that be tightened by 15N•m)(spanner width across flat 19mm - for items that be tightened by 50N•m)(spanner width across flat 24mm - for items that be tightened by 80N•m)• Spanner: (13mm)• Closed wrench: (27mm)• Adjustable end wrench: (Width 0-25mm)• Hexagon socket wrench: (Width across flat 5mm)Step 1:Attach check valve (5) to the body (1). Note the installation direction of the check valve. Face the processing surface (with a dent at the center) toward the screw side.Processed Surface(with a dent)Step 2:Assemble the vent valve seat (15) and vent valve seat gasket (16) to the cover (2). Apply lubricant to the vent valve seat gasket and assemble it with the vent valve seat. Tighten the vent valve seat with the torque of 80N•m using the spanner-type torque wrench (width across flat 24mm).Spanner TypeTorque Wrench(width across flat 24mm)8Step 3:Assemble a set of the inlet valve (6) and inlet valve seat gasket (17) with the cover (2). Apply lubricant to the inlet valve seat gasket and assemble it with the inlet valve seat. Tighten the inlet valve seat with the torque of 50N•m using the spanner-type torque wrench (width across flat 19mm).Step 4:To assemble the valve (P) (3) with the cover (2), align the two cover pins with the valve (P). Use two bolts (10) for assembly with the spanner (width across flat 13mm).Step 5:Assemble the float (P) (7) with the valve (P)(3). Insert the hexagon nut (18) to the float arm. Fix the float arm using an adjustable end wrench. Tighten the hexagon section (width across flat 17 mm) of the float (P) with the torque of 15 N•m using a spanner-type torque wrench.Step 6:Replace the gasket (9) with a new one. Before assembling a new one, apply the paste on the entire surface and inside surface of the gasket.9Spanner Type Torque Wrench(width across flat 24mm)Vent Valve SeatInlet ValveCover2 PinsFloat Arm Section Adjustable End WrenchSpanner Type Torque Wrench(width across flat 17mm)Inside Surface10Step 7:Attach the new gasket to the body (1). Confirm that the gasket is completely set to two pins on the body.Step 8:Attach the cover (2) to the body (1). Confirm that the valve section of valve (P) (3) is completely inserted to the valve seat inside. (see drawing below) Attach the cover. Tighten the bolt (11) with the torque of 35 N?m using the torque wrench of the hexagon socket wrench (width across flat 5 mm).* Please confirm that the cover (2) attaches to the bolt (2 places) on the body (1) before tighten the hexagon bolt (11). Failure to do so may results in a broken bolt or inadequate assembly.* Do not use the hexagon L-type wrench for tightening; otherwise, the hexagon hole might be damaged or assembly failures might occur due to insufficient tightening.Step 9:Attach the strainer (8) (cylindrical), strainer gasket (20), and strainer cap (19) to the cover (2). Insert the strainer and strainer gasket to the strainer cap, and screw them into the cover using the closed wrench (width across flat 27 mm).›N ormal×AbnormalPin PositionGasketValve SeatPin PositionValve SectionValve Seat(cross section diagram)Valve Section is SeparatedValve SeatTorque WrenchHexagon Socket WrenchNormal AbnormalReplacement procedure of partsReplacement procedure of gasketDisassemble the gasket in the procedure of step 2 of 9.5.2 Disassembly method. Replace and assemble it in the procedure of steps 6, 7, and 8 of 9.5.3 Assembly procedure.Replacement procedure of float (P)Disassemble the float in the procedure of steps 2 and 3 of 9.5.2 Disassembly method. Replace and assemble it in the procedure of steps 5, 6, 7, and 8 of 9.5.3 Assembly procedure.Replacement procedure of valve (P)Disassemble the valve in the procedure of steps 2, 3, and 4 of 9.5.2 Disassembly procedure. Replace and assemble it in the procedure of steps 4~8 of 9.5.3 Assembly procedure.Replacement procedure of a set of inlet valveDisassemble the inlet valve in the procedure of steps 2~5 of 9.5.2 Disassembly procedure. Replace and assemble it in the procedure of steps 3~8 of 9.5.3 Assembly procedure.Replacement procedure of vent valve seatDisassemble the vent valve seat in the procedure of steps 2, 3, 4 and 6 of 9.5.2 Disassembly procedure. Replace and assemble it in the procedure of steps 4~8 of 9.5.3 Assembly procedure.Replacement procedure of check valveDisassemble the check valve in the procedure of steps 2 ~7 of 9.5.2 Disassembly procedure. Replace and assemble it in the procedure of steps 1, 6~8 of 9.5.3 Assembly procedure.Replacement procedure of strainer and strainer gasketDisassemble the strainer and strainer gasket in the procedure of step 1 of 9.5.2 Disassembly procedure. Replace and assemble it in the procedure of step 9 of 9.5.3 Assembly procedure.WasteTo dispose (classify and dispose) the product, check the materials of each part, referring to the delivery drawings.Armstrong Condensate Management Group, 221 Armstrong Blvd., Three Rivers, MI 49093 – USA Phone: (269) 279-3601 Fax: (269) 279-3150www.armstrong IB-118 9/07。

Extraction

i 0 i i i i i 0 i i i i i 0 i i i i
II. The alபைடு நூலகம்orithm
2
are transformed into simpler, hypercuboidal decision regions 5], 6]. We will not discuss this problem here. Logical (linguistic) input variables s for continuous input data components x may be obtained by dividing the data in distinct (for crisp logic) sets: IF (x 2 X ) THEN (s = T). For example, s = s may designate the fact that the feature s is small, and s = :s that it is not small. Each quantized feature s will have two or more values represented by a vector V 1 = (+1 ;1 ;1:::) for the rst value, V 2 = (;1 +1 ;1:::) for the second value etc. Interpretation of the activation of the MLP network nodes is not easy 7]. To facilitate such an interpretation a smooth transition from MLP to a logical-type of network performing similar functions is advocated. This is achieved by: a) increasing the slope of sigmoidal functions to obtain crisp decision regions b) simplifying the network structure by inducing the weight decay through a penalty term c) enforcing the integer weight values 0 and 1, interpreted as 0 = irrelevant input, +1 = positive and ;1 = negative evidence. These objectives are achieved by modifying the error function: 2 E(W) = 1 Y ( ) ; M X( ) + 21 W 2 + 22 W 2 (W ; 1)2(W + 1)2 (1) 2 Two additional terms are added to the standard mean square error. The rst term, scaled by 1 hyperparameter, encourages weight decay, leading to skeletonization of the network and elimination of irrelevant features. The second term, scaled by 2 , forces the remaining weights to approach 1, facilitating easy logical interpretation of the network function. In the backpropagation training algorithm these new terms lead to the additional change of weights: 1 W + 2 W (W 2 ; 1)(3W 2 ; 1). This approach may also be justi ed from the Bayesian point of view 8]. The cost function speci es our prior knowledge about the probability distribution P (W jM) of the weights in our model M. Since we model a network for classi cation tasks and expect crisp logical decision the prior probability of the weight values is:

parallel manipulators

A general strategy based on the Newton±Euler approach for the dynamic formulation of parallel manipulatorsBhaskar Dasgupta a,*,Prasun Choudhury baDepartment of Mechanical Engineering,Indian Institute of Technology,Kanpur 208016,India b Department of Mechanical Engineering,Northwestern University,2145Sheridan Ave,Evanston,IL 60208,USAReceived 6June 1997;received in revised form 31August 1998;accepted 3September 1998AbstractThis paper presents a general strategy based on the Newton±Euler approach to the dynamic formulation of parallel manipulators.It is shown that,for parallel manipulators,through appropriate selection and ordering of the equilibrium equations,the Newton±Euler method can be used with advantage not only for inverse dynamics computations,but also for the derivation of dynamic equations in closed form.The proposed strategy has been illustrated through its application to several planar and spatial manipulators.Cases of parallel manipulators requiring particular considerations are also discussed with recommendations of special measures to be taken in di erent classi®ed cases.#1998Elsevier Science Ltd.All rights reserved.1.IntroductionEuler±Lagrange formulation and Newton±Euler formulation are the two broadly adopted approaches for dynamic analysis of robot manipulators.In the Euler±Lagrange approach,the complete physical description of the manipulator is ®rst incorporated in the Lagrangian in terms of a set of generalized coordinates and velocities,and then a systematic procedure is followed to develop the Lagrangian equations of motion.On the other hand,in the Newton±Euler approach,Newton's law and Euler's equation for linear and angular motion are directly applied to individual bodies.It is held that the Newton±Euler approach is numerically e cient so far as inverse dynamics computation is concerned and the Euler±Lagrange approach is Mechanism and Machine Theory 34(1999)801±8240094-114X/99/$-see front matter #1998Elsevier Science Ltd.All rights reserved.PII:S0094-114X(98)00081-0*Corresponding author.Tel.:++91-512-597095;fax:++91-512-590260.E-mail address:dasgupta@iitk.ac.in (B.Dasgupta)better suited for the derivation of closed-form dynamic equations of the system (see p.142of Fu et al.[1],for example).While the above statement is by and large true for conventional serial manipulators,the case of parallel manipulators warrants closer exploration in this regard.The kinematics and dynamics of parallel manipulators show signi®cant contrasts to that of serial manipulators (see Waldron and Hunt [2]for an elegant description)and often necessitate radical departures from conventional methods for their analysis as discussed by Dasgupta [3].Again,joint variables appear as the natural choice for generalized coordinates in the case of serial manipulators while the actuated joint variables are not enough for complete description of parallel manipulators.In the case of parallel manipulators,a joint-space formulation leads to a system of di erential algebraic equations involving Lagrange multipliers.The computations of Lagrange multipliers in the inverse dynamics can be avoided by the method of Nakamura and Ghodoussi [4],but it involves the so-called virtual actuations (in lieu of Lagrange multipliers)which have to be eliminated for developing the closed-form dynamic paratively,it is generally easier to derive the dynamic equations of parallel manipulators in the task-space.In the tutorial on the Newton±Euler method for derivation of closed-form dynamic equations of serial manipulators,Driels et al.[5]observed that ``as the complexity of the robot model increases,the NE method becomes a viable competitor with Lagrangian methods for closed-form equation generation''.This fact is more apparent in the case of a parallel manipulator,the Lagrangian of which is very complicated.So far as the Newton±Euler method is concerned,the only major di culty in the derivation of closed-form dynamic equations is in the elimination of the joint reactions,as mentioned by Kane and Levinson [6].However,contrary to the view expressed in [6],the application of the Newton±Euler approach is more economical in the case of parallel (or hybrid)manipulators than in serial manipulators,as shown in the present paper.The idea is to reduce the computational burden by a selective consideration of equilibrium equations such that many of the joint reactions never come into picture and others are eliminated by taking the appropriate components of forces/torques in a manner similar to the method of Sugimoto [7]by the orthogonalization of screws.First of all,it is noted that,for parallel and closed-loop manipulators,development of dynamic equations is more straightforward in task-space than in joint-space.Secondly,Newton's law and Euler's equation can be directly applied in an economical way in the sense that only those equilibrium equations of individual bodies need to be considered which contribute in relating the end-e ector motion to the actuation forces and torques.In view of these two aspects,the Newton±Euler method has been recently applied to a few speci®c parallel manipulators [8±10]with signi®cant advantage.The present paper focuses on the dynamic analysis of parallel manipulators in general by the Newton±Euler approach through the generalization of the above-mentioned strategy and enumerates systematic guidelines for both the inverse dynamics problem and the derivation of closed-form dynamic equations.Although these two procedures use the same set of equations,the two strategies di er from each other in the sense that for inverse dynamics all accelerations are determined from the (known)acceleration components of the end-e ector,while for derivation of closed-from dynamic equations they are evaluated as linear functions of the (unknown)acceleration components of the end-e ector.Although the inverse dynamics also can be solved from the dynamic equations,it is noticed that the alternative suggested results in a computationallyB.Dasgupta,P.Choudhury /Mechanism and Machine Theory 34(1999)801±824802e cient scheme.The above procedure has been applied to a few parallel and hybrid manipulators to demonstrate the versatility of the approach.In the next section,the salient features of the proposed strategy and the algorithmic steps are outlined.In Section3,the considerations necessary in various cases of robot architectures are recommended.In Sections4and5,the application of the method is illustrated by various planar and spatial examples.Finally,in the last section,the work presented in the paper is summarized with a discussion on the scope and applicability of the proposed method.2.The dynamic formulation strategyThe Newton±Euler method of dynamic formulation is based on the direct application of Newton's law and Euler's equation in the formF m a 1andMrÂF r cgÂm a I a oÂI o 2to individual bodies.This yields six scalar equations for each body.The subject matter of this section is the set of principles for selection and ordering of the appropriate equations for various bodies in order to relate the end-e ector acceleration components to the actuator forces/torques for parallel manipulators.A parallel robot manipulator is one which has its end-e ector(platform)connected to the frame(base)through a number of partially actuated kinematic chains(legs)in-parallel.A parallel manipulator in the strict sense would have a single actuation in each leg.Similar manipulators with more than one actuations in a leg,in fact,constitute a sub-class of hybrid manipulators,but can be analyzed by the methods pertaining to parallel manipulators.In the case of open-chain serial manipulators,the con®guration can be completely described in terms of the actuated joint variables and the direct kinematics is straightforward and unique. This makes the joint-space formulation attractive for the dynamics of serial manipulators.On the other hand,the direct kinematics of parallel manipulators is found to be quite complicated with possibilities of branching.Therefore,a joint-space formulation of dynamics is both complicated and undesirable for parallel manipulators.For parallel manipulators,the inverse kinematics is comparatively simpler which makes task-space dynamic formulation appropriate. In this paper,the dynamic formulation of parallel manipulators is considered in task-space. The salient features and steps of the strategy are described in the following.2.1.Decoupling of the legsFor a task-space dynamic formulation,the aim is to develop the equations of motion (namely,Newton's and Euler's equations)for the platform.For writing these equations,the forces/torques exerted by the legs on the platform appear as unknowns.Thus,it is necessary to analyze each leg with the intent to evaluate its contribution to the force system acting on theB.Dasgupta,P.Choudhury/Mechanism and Machine Theory34(1999)801±824803platform in terms of the actuation(s)in that leg.The ®rst step in the strategy is to determine the position,velocity and acceleration of the platform-connection-point of each leg in terms of the task-space coordinates and their derivatives.Once this is done,each leg gets decoupled from the rest of the system and its kinematics and dynamics have to be analyzed for its reaction at the platform-connection-point.2.2.Kinematics and dynamics of a legFrom the position,velocity and acceleration of the platform-connection-point,the kinematics of the leg is solved up to the evaluation of the linear acceleration of the centres of gravity and the angular accelerations of all the links in the leg.In addition,from the con®guration of the leg,the moment of inertia of each link is transformed to the global basis.The next step is to consider the dynamics of the leg and to select the appropriate components from the equilibrium equations.At this point,let us assume that the number of task-space coordinates is equal to the number of degrees of freedom of the manipulator and also equal to the DOF's allowed to the platform by each leg.Let us call this situation the ``standard''case 1of parallel manipulators.Then,the number of reaction components at the platform-connection-point will be the same as the number of freedoms available in the leg (except those at the platform-connection),i.e.number of task-space coordinates less the degrees of freedom of the platform-connection.For example,in a 6-DOF standard parallel manipulator with spherical joint at the platform-connection-point,there will be three components of force (and no moment)reaction and the leg should have joints giving a total of three degrees of freedom.From the above,it is apparent that considering only those components of equilibrium equations where freedom is available is su cient to determine the reaction of the leg to the platform in terms of the actuations in the leg.First,the equilibrium of the most distal (farthest from the base)link is considered and the forces or moments (or a combination,as the case may be)on it along the screw of freedom available at the preceding joint are equilibrated.Examples of various choices depending upon the preceding joint are as follows:1.Prismatic joint :force equilibrium along the sliding directionÐone scalar equation.2.Revolute joint :moment equilibrium about the revolute axisÐone scalar equation.3.Screw joint :appropriate linear combination of force and moment equilibrium along and about the screw axisÐone scalar equation.4.Cylindrical joint :force equilibrium along the joint axis and moment equilibrium about itÐtwo independent scalar equations.5.Universal joint :moment equilibrium about both the axes of freedomÐtwo independent scalar equations6.Spherical joint :moment equilibriumÐa vector equation with three independent scalar components.1Measures to be taken in ``non-standard''cases will be discussed in Section 3B.Dasgupta,P.Choudhury /Mechanism and Machine Theory 34(1999)801±824804Next,the combined equilibrium of the farthest and the penultimate links is considered and the equation(s)involving components corresponding to the joint preceding the penultimate link is/ are retained.Repeating this procedure,at the®nal step,the equilibrium of the entire leg is considered and component(s)corresponding to the freedom allowed by the base joint is/are taken.Thus,we get exactly the requisite number of equations necessary for solving the reaction components at the platform-connection in terms of the actuator force/torques.These equations are solved,either together or in some preferred order(depending upon the manipulator structure),and the reaction at the platform-connection-point is determined.It is to be noted that the above method ensures that the reactions of the joints in the leg are automatically eliminated from these equations.2.3.Algebraic manipulations for standard expressionsThe above exercise often results in complicated expressions involving the quantity X, representing platform acceleration,in multiple products of vectors in various terms.For inverse dynamics computations,where X is known,the expressions can be evaluated numerically at each step and the®nal expression for the reaction of the leg to the platform is easily obtained in the formF h X t c X, X, X 3 For the purpose of deriving the dynamic equations in closed form,however,X is to be treated as unknown and all the terms involving X have to be clubbed in the form QX,where Q is a matrix of appropriate dimension.For this purpose,apart from the usual operations of vector algebra,the following two working rules will be used for correspondence between vector algebra and matrix notations.Rule I.With arbitrary vectors a and b,ÀaÁ X Áb bÀaÁ XÁbÀa T XÁba T XRule II.With arbitrary vector a,for planar systems(X$R2)aÂ X a1 X2Àa2 X1 Àa2a1 X a T c Xwhere a_is the vector obtained by rotating vector a by a right angle in anticlockwise(positive) sense;and for spatial system(X$R3)aÂ X ~a XwhereB.Dasgupta,P.Choudhury/Mechanism and Machine Theory34(1999)801±824805~a P R 0Àa 3a 2a 30Àa 1Àa 2a 10Q S is the skew symmetric matrix corresponding to the vector a .Using these rules in the dynamic equations and carrying out the necessary algebraic manipulations,the reaction of the leg to the platform can be expressed in the formF h X t Q X X V X , X 42.4.Kinematics and dynamics of the platformAfter the expressions for the reactions of the legs 2are developed,the equilibrium of the platform is considered and dynamic equations for the platform are written.These equations now relate the actuator forces/torques to the platform acceleration.In inverse dynamics computations,using Eq.(3),all the actuator forces/torques can be solved from a linear system.On the other hand,for developing closed-form dynamic equations,Eq.(4)can be used to develop the complete dynamic equation of the system in task-space in the formM X XZ X , X H X t R Ext 5 whereM M platlegs M leg and Z Z plat legs Z legincorporate the contributions from all the legs as well as from the platform.The force transformation matrix H transforms the actuator forces/torques to task-space while R Ext is the external force system acting from the environment on the platform (end-e ector).2.5.SummaryThe steps involved in the proposed strategy of dynamic formulation can be summarized as below.1.For each leg,1.1.Find the position,velocity and acceleration of the platform-connection-point from (or in terms of)the task-space coordinates and their derivatives.1.2.Solve the kinematics of the leg for position,velocity and acceleration.1.3.Let m be number of links in series in the leg.Let l 1,l 2,F F F ,l m denote the m links and j 1,2Analysis for all legs can be performed in parallel due to the decoupling of legs from one another.B.Dasgupta,P.Choudhury /Mechanism and Machine Theory 34(1999)801±824806B.Dasgupta,P.Choudhury/Mechanism and Machine Theory34(1999)801±824807j2,F F F,j m denote the joints,starting from the base.Then,for i=1±m,consider the equilibrium of links l mÀi+1to l m and take its component(s)corresponding to the freedom(s)allowed by joint j mÀi+1.1.4.From the equations obtained above,solve the reaction at the platform-connection-pointin terms of the actuation(s)in the leg(for inverse dynamics)or express the reaction in terms of the actuations and the platform accelerations X(for deriving closed-form dynamic equations).2.Consider equilibrium of the platform and write Newton's and Euler's equations for it.Solve the actuator forces/torques from these equations(for inverse dynamics)or simplify the equations to the standard form(resulting in the closed-form dynamic equations).Two parallel strategies for inverse dynamics and for deriving closed-form dynamic equations based on the same theme have been described above.This might seem redundant because the inverse dynamics can be solved from the dynamic equations also.However,it should be noted that,compared with deriving the equations in closed form and then using them,following the direct strategy turns out to be signi®cantly economical for the inverse dynamics problem.In the examples presented in the paper,however,only the derivation of closed-form dynamic equations will be demonstrated for the sake of brevity and the inverse dynamics problem will not be pursued separately.3.Various standard and non-standard casesIn the above,we designated as the``standard''case the situation in which the number of task-space coordinates is the same as the number of degrees of freedom of each leg.When the task-space coordinates are greater or lesser in number,we have``non-standard''cases that warrant special considerations for dynamic formulation.Even in``standard''cases,there are di erent situations due to the possible hybrid nature of the manipulator or due to redundancy. Although all standard cases can be modeled by the strategy as explained in Section2,without any modi®cation,the form of the resulting system of equations may vary from case to case.All these standard and non-standard cases are brie¯y discussed in the binations of various cases are also possible where measures necessary for individual cases taken together will su ce to yield a complete and consistent modeling.3.1.Ordinary non-redundant parallel manipulatorsThis is the simplest case of parallel manipulators where(1)number of task-space coordinates (n)is the same as the number of degrees of freedom of the manipulator and also as the number of legs,and(2)each leg has n degrees of freedom exactly one of which is actuated. Examples of this case are®ve-bar2-DOF manipulators,the eight-bar3-DOF manipulators and the Stewart platform with six UPS(universalÐprismaticÐspherical)legs.The resulting system of dynamic equations(Eq.(5))will have a square H matrix with one column per leg(i.e.per actuation).Although this is a standard case and the so-called simplest one so far as theformulation is concerned,the equations can turn out to be quite complicated depending upon the kinematic structures of the legs.Legs comprising of fewer links (and hence multi-DOF joints)facilitate the application of the Newton±Euler formulation.In the most complicated cases,for example 6-DOF parallel manipulator with six 6R legs,the Newton±Euler method will have marginal or no advantage over the Euler±Lagrange method so far as derivation of closed-form dynamic equations is concerned.The task-space analysis,however,will still retain the advantage.3.2.Hybrid manipulatorsThe complete class of hybrid manipulators is quite wide with numerous possibilities of kinematic structures and is beyond the scope of the present paper.However,platform manipulators with multiple actuations in at least one leg constitute a sub-class of hybrid manipulators and can be analyzed by the methods for analysis of parallel manipulators.Examples of such hybrid manipulators are the single-loop six-bar 3-DOF planar manipulator discussed in Section 4and the two three-legged (3-PRPS and 3-RRRS)manipulators discussed in Section 5.These also are standard cases for the proposed method and no special measure is necessary.However,task-space formulation has reduced advantage in these manipulators.With fewer legs and more number of actuations in individual legs,joint-space analysis may become competitive and in the extreme case,pletely serial manipulator,joint-space analysis is ideal.3.3.Manipulators with static redundancyRedundant manipulators are characterized by more number of actuations than degrees of freedom.If the platform is supported by more number of (actuated)legs than necessary,we have static redundancy.The concept of static redundancy in parallel manipulators and its role in singularity reduction has been detailed by Dasgupta and Mruthyunjaya [11].Examples of statically redundant parallel manipulators can be the four-legged 3-DOF planar parallel manipulator or a seven-legged version of the Stewart platform.These are also examples of standard cases for the proposed method with force transformation matrix H being rectangular to accommodate the redundant actuation and the summation for M and Z being carried over all the legs.In case the redundant leg is not actuated (kept free),the matrix H can be made square,although the dynamic terms (M and Z )have to account for the unactuated leg(s)also.3.4.Manipulators with actuation redundancyParallel manipulators can have actuation redundancy if some of the passive joints are replaced by active ones.For example,the ®ve-bar 2-DOF manipulator discussed in Section 4can be made to have actuation redundancy by providing actuations to both the joints in one (or both)of the legs.This is also a standard case and modeling is similar to the case of hybrid manipulators,although the H matrix in the ®nal system turns out to be rectangular.B.Dasgupta,P.Choudhury /Mechanism and Machine Theory 34(1999)801±8248083.5.Manipulators with kinematic redundancyKinematically redundant parallel(rather hybrid)manipulators constitute a non-standard case for the proposed strategy.They are characterized by one or more of the legs having more degrees of freedom than the number of task-space coordinates with additional actuator(s)as well.For example,replacing one of the legs of the3-RRRS manipulator by an RRRRS leg and actuating three of the revolute joints will introduce kinematic redundancy in that leg.Such redundancy can be useful in avoiding kinematic singularities,obstacles or interference of legs. In such situations,the task-space coordinates alone cannot describe the con®guration completely due to the in®nite possible con®gurations of the redundant leg(s).To apply the Newton±Euler method to such a manipulator,from each kinematically redundant leg, additional joint variables(equal in number to the degree of redundancy)can be included in the set of generalized coordinates and the steps in the procedure will automatically generate an equal number of additional equations.The®nal system of dynamic equations can be expressed in a partitioned form asM xx M x y M y x M yy !Xy!Z x Zy!H x Hy!t R Ext0!6where X and y consist of task-space variables and additional joint-space variables,respectively.3.6.Manipulators with passive freedomLegs of a parallel manipulator can have passive degrees of freedom which do not contribute to kinematic/static relationships,but do a ect the dynamics through inertia coupling,coriolis and gravity terms.A good example of this case is the Stewart platform with SPS legs,i.e.legs with spherical joints at both the base and the platform,giving the passive freedom of axial rotation of legs.Such manipulators exhibit a non-standard case and can be tackled by the proposed strategy by including additional coordinates corresponding to the passive freedoms in the set of generalized coordinates.Since dynamic analysis of a leg is performed by the method on the basis of joint freedoms,additional dynamic equations corresponding to these freedoms are generated as a matter of routine procedure.The®nal system of equations can be arranged in the formM xx M x f M f x M ff !XF!Z xZ f!H x t0!R Ext0!7In fact,this non-standard case can be considered as a sub-case of kinematically redundant one with the redundant actuation®nally set to zero.3.7.Manipulators with inadequate actuationsWhen the degrees of freedom allowed to the platform through legs is less than the natural dimension of the task-space,the degrees of freedom of the manipulator is still lesser and the actuators are unable to give arbitrary motion to the platform.Although a set of coordinatesB.Dasgupta,P.Choudhury/Mechanism and Machine Theory34(1999)801±824809out of the natural task-space variables can be chosen for control as the ``output'',these coordinates cannot describe the platform pose completely.The 3-RPS parallel manipulator discussed in Section 5is an example of this case.The ®ve-bar 2-DOF manipulators discussed in Section 4also will fall under this case if a point on any of the distal links other than their connection-point is considered as the output,thereby making the orientation also necessary to determine the connection-point in terms of the task-space variables.In such a case,the dynamic analysis of a leg does not yield all the reaction components at the platform-connection.The required number of equations are,however,found by considering the equilibrium of the platform.The resulting system turns out to be a system of di erential algebraic equations with constraints on the legs.4.Planar manipulatorsIn this section,the dynamic formulation strategy is illustrated with two rudimentary planar manipulators,namely ®ve-bar 2-DOF manipulators with prismatic and revolute actuations.In addition,3-DOF planar manipulators are also discussed in brief.4.1.Five-bar with prismatic actuationsThe ®ve-bar mechanism shown in Fig.1is a 2-DOF regional manipulator with the end-e ector at point ``p'',the position of which is denoted by t and gives the generalized coordinates.In this case,as the output-point itself is the platform-connection-point (for the point-platform),the analysis starts with the legs.For each of the legs,denoting the leg vector,leg length and unit vector along the leg by S ,L and s ,respectively (omitting the leg-index for convenience),the position kinematics yieldsS t Àb ;L k S k ;s S aLFig.1.Five-bar with prismatic actuations.B.Dasgupta,P.Choudhury /Mechanism and Machine Theory 34(1999)801±824810From this,the centres of gravity of the lower and upper parts of the leg are transformed to a ®xed frame at the base point parallel to the global frame and are denoted by r d and r u.The sliding velocity at the prismatic joint and the angular velocity of the entire leg are given byL sÁ t;W scÁ t a Lwhere the subscript_denotes anticlockwise rotation of a vector through a right angle. Acceleration analysis of the leg gives the sliding acceleration at the prismatic joint and the angular acceleration of the entire leg asL sÁ t W2L 8 andA 1LÀs cÁ tÀ2W LÁ9From this the accelerations of the centres of gravity of the lower and upper links are given bya d A r d cÀW2r d 10a u L s A r u cÀW2r u 2 LW s c 11 To get the reaction forces at the output point,we®rst consider the force balance of theupper part of the leg in the direction of the leg and thereafter take into account the moment equilibrium of the entire leg about the base point yielding the required equilibrium equations asm u sÁ gÀa u f F a 12 andm u r uÂg m d r dÂg Àm u r uÂa u Àm d r dÂa d À I u I d A LF p 13 where F a and F p denote the components along and perpendicular to the leg respectively,while f is the actuation force at the prismatic joint.The resultant reaction force is expressed asF F a s F p s cwhich upon substitution from Eqs.(12)and(13)and simpli®cation yieldsF f sÀQ t U 14 whereQ m u ss T a1L2s c s T cm u r uÂsLÀss T c s c s TÁ。

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a r X i v :h e p -p h /0207103v 1 8 J u l 20021Extraction of the Generalized Parton Distribution H (ξ,ξ,t )from DVCSV.A.Korotkovdx B dyd |t |dφ=α3x B y1+4x 2B M 2/Q2T2to the azimuthal angleφ(see Eq.s(25-27)in Ref.[6]).Note that for the DVCS process the skewedness variable can be determined byξ=x B/(2−x B).2.Projection for a future DVCS measurement at HERMESThe HERMES collaboration will upgrade their apparatus with a recoil detector[8] to measure the single beam-spin and the beam-charge asymmetries using an unpolar-ized proton target.Prospects for a measurement of the single beam-spin asymmetry are investigated in this paper.For the projection of the expected statistical accuracy the the-oretical approach of Ref.[6]was adopted.In the analysis described belowﬁve diﬀerent versions of parameterizations for twist-2GPDs are used.They are referred to as(A)to (E)(for details see Ref.[9]).The twist-3GPDs were taken to be zero for simplicity. The projections of the statistical accuracy for measurements of the single beam-spin asymmetry at HERMES were calculated for an integrated luminosity of2fb−1,corre-sponding to one nominal year of data taking.The HERMES acceptance for the detection of the scattered electron,the real gamma and the recoil proton has been taken into account.The following kinematic cuts were applied:E e′>3.5GeV,Eγ>0.8GeV, P p′>0.2GeV/c,W2>4GeV2,Q2>1GeV2,and15<Θγγ∗<70mrad.Here, W2=(P2+q2)2andΘγγ∗is the polar angle between virtual and real photons.The remarkably improved accuracy in measuring the variable t with the recoil detector will allow accurate studies of kinematic dependences of the asymmetry.For this purpose it is convenient to deﬁne an appropriate sinφmoment1of the asymmetry:A sinφLU=2· 2π0dφsinφ{dσ(−→e p)/dφ−dσ(←−e p)/dφ}(2−x B)2 4(1−x B) HH∗+ H H∗ −x2B HE∗+EH∗+ H E∗+ E H∗− x2B+(2−x B)2t4M2 E E∗ .(3)3x B10Figure 1.Projected statistical accuracy for a future HERMES measurement of the A sin φLU moment of the DVCS single beam-spin asymmetry as a function of x B for two regoins in −t .The calculations,using GPD model version (E)(see Ref.[9]),are based on an integrated luminosity of 2fb −1.The numerator of Eq.(2)is proportional to Im C Iunp ,where C I unp =F 1H +x B4M 2F 2E (4)Here,F 1and F 2are the Dirac and Pauli form factors.From the expressions (3)and (4)it may be seen that at small values of t and x B the main contributions come from the ﬁrst terms of both expressions.This observation can be checked numerically using diﬀerent models for GPDs.In the following the region of small −t (<0.15GeV 2)is considered.Expression (3)can be regrouped into two terms,C DVCSunp =B 1+B 2,with B 1=41−x B4-0.200.20.40.60.811.210-1-0.200.20.40.60.811.210-1x B BH DVCSDVCS (B 1)DVCS (B 2)a)x Bb)R e l a t i v e C o n t r i b u t i o nFigure 2.Relative contribution of the BH and DVCS cross sections to the denominator of Eq.(2).The relative contributions coming from the DVCS cross section parts proportional to B 1and B 2are shown also.Results for the GPD versions (A)and (B)are shown in panels a)and b),respectively.-0.200.20.40.60.811.210-1-0.200.20.40.60.811.210-1x B HH∼Ea)x Bb)R e l a t i v e C o n t r i b u t i o nFigure 3.Relative contribution of terms from Eq.(4)induced to the numerator of Eq.(2)due to the amplitudes H , H,and E .Results for GPD versions (A)and (B)are shown in panels a)and b),respectively.be analysed as a function of Im H only,appears to be quite reasonable.In this scenario,the moment (2)can be expressed in the following form:A sin φLU=2·d Ωsin φdσI0/d Ω·Im H5 extract Im H in a parameterized form from future HERMES measurements.A simple parameterization with two free parameters c1and c2,Im H(ξ)=c1ξc2,(7) was adopted following an observation made in Ref.[10].Fits to the projected moment asymmetry in the region−t<0.15GeV2,performed on the basis of Eq.s(6)and(7),show good descriptions of the x B-dependence of A sinφLU.The results of theﬁts to the projected moments for GPD model versions(A)and(B),taken as examples,are shown in Fig.4. Typical values ofχ2/nd f are(4÷6)/6if every point is varied in limits of±3σof its projected error.Deviations of the extracted function Im H from that used as input for the projections are found to be small within the expected statistical accuracy.10xBxB10Figure4.Results of aﬁt to the projected moments for GPD model versions(A)and(B) on the basis of Eq.s(6)and(7),calculated for−t<0.15GeV2.To leading order inαs,the determination of Im H corresponds to a measurement of the quantity q e2q(H q(ξ,ξ,t)−H q(−ξ,ξ,t)),taken along the diagonals x=±ξ(cf.e.g. Eq.(19)in Ref.[9]).The fully correlated1σerror bands for a future measurement of this quantity at HERMES in the region−t<0.15GeV2,as obtained after theﬁt,are shown in Fig.5for GPD model versions(A)and(B).The systematic uncertainty of this simple analysis method,as depicted in Fig.5,was estimated to be the average of the deviations between reconstructed and input functions for all versions of GPDs and was found to be smaller than the envisaged statistical uncertainty.4.ConclusionsNumerical studies carried out for diﬀerent models of GPDs have shown that the mostsigniﬁcant contribution to A sinφLUat small−t and0.03<x B<0.3is originating from Im H.This observation allows to develop a procedure for the extraction of the General-ized Parton Distribution H from future HERMES measurements of the single beam-spin asymmetry.A simple parameterization of Im H with two free parameters allows to de-scribe a dependence of A sinφLUon x B at small t.Deviations of the extracted function6Im H from that used as input for the projections are small inside the expected statistical accuracy.34567891020304010-210-1ξ(A)(B)Σ e q 2 ( H q(ξ,ξ,t ) - H q(-ξ,ξ,t ) )Figure 5.Projection for a future HERMES measurement,based on 2fb −1,of q e 2q (H q (ξ,ξ,t )−H q(−ξ,ξ,t )),shown in dependence of ξand x B simultaneously.The fully correlated 1σerror bands (solid lines)show the projected statistical accuracy for the two GPD model versions (A)and (B),chosen as examples (see Ref.[9]).The hatched bands represent the linear sum of the statistical 1σerror and a systematic error estimated to be due to the approximations inherent in the used analysis method.We are grateful to M.Diehl and R.Kaiser for a careful reading of the manuscript.REFERENCES 1. 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