A Graphical Rule Language for Continuous Dynamic
Systems
Alonso G′o nzalez,Carlos J.Rodr′?guez Diez,Juan J.
Departamento de Inform′a tica
Universidad de Valladolid
Spain
e-mail:{calonso,juanjo}@infor.uva.es
Abstract.A graphical language to represent rules is described.It
has been designed for on-line applications on continuous systems.Rule
conditions are represented using pipe diagrams and its edition is simple
enough for a non-expert computer user.In order to use this language in
dynamic systems,elements to deal with uncertainty and time has been
introduced.Temporal expressions involving quali?ers like“always”and
“generally”over fuzzy sets like“x is high”are available.The syntax
and semantics of these primitives and of their combination is presented.
The graphical representation and edition of the previous elements is
discussed.An application based on this language has been developed
to allow the user to adapt the operation of a monitoring and diagnosis
system.The methodological approach to the application development
is brie?y discussed.
1Introduction
A di?culty in the generalised use of Knowledge Based Systems(KBSs)in some impor-tant domains is the necessity of constant update.This is particularly true in industrial applications,where factories with the same purpose may be very di?erent.Even the same factory can vary strongly its operation with time.
After some experience with KBSs working on line on continuous processes[2,3],it became evident that a necessary condition to obtaining full operative KBS applications was that system update and maintenance of the knowledge base must be done by the end users[11],experts in the domain but not professional programmers.And we thought that the basic step to achieve that objective was to endow the end user with a tool that supported a graphical,visual,language which allowed references to the basic concepts used by the users to reason about the problem domain.
Since most knowledge in expert systems is expressed with rules and this concept is simple enough to be understood by a user,we opted for a visual rule language.A visual environment is nowadays assumed,but visual languages[5,6]are less https://www.doczj.com/doc/565261929.html,ing a visual language to express rules allows a more intuitive programming and maintenance, even for a non-expert computer user.The same language can be used as a debugging mechanism and as an explanation aid to the user.The notation chosen to represent rule conditions was based on directed acyclic graphs,where the nodes are simple conditions. They allowed expressing simultaneously the logical(conjunction,disjunction)and the temporal issues(sequentiality,parallelism)of a condition.
In a language designed for continuous dynamic systems some consideration,regard-ing uncertainty[9]and temporal aspect[7],must be done.Keeping in mind that we
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wanted to represent sentences like“between8:00am.and8:30am.the pH was high”or “during the last three hours there has been some shortage of fuel”,we opted for a fuzzy logic[13,14]approach to uncertainty.A discrete linear point based time model was se-lected[1],allowing references towards the past with time stamps relative to the present evaluation time.Nevertheless,approximate values at precise time points weren’t enough to capture the rich temporal language commonly used at a factory control room.It seemed that vague properties held during time intervals were highly signi?cant.Hence, we extended the temporal model de?ning some fuzzy quali?ers[8],which operate on fuzzy values over time intervals.Another interesting temporal element is the possibility of future references.This is possible with the use of waits.
The paper is organised as follows.The language primitives and their combination to form rules in Sect.2.Section3discuses the graphical representation of the previous elements.An application that uses this language and some topics about its development are presented in Sect.4.Finally,Sect.5concludes.
2The Language
The majority of the data to be processed in a dynamic environment are temporal series arising form sensor interfaces.As we needed fuzzy values over historical sensors data, we de?ned indicators,which kept the present and past values of sensors,although an indicator value might be de?ned applying a function to any set of measurements. Indicators had associated situations,that allowed to de?ne fuzzy sets over the sensors’range.In this way,we paved the way to represent sentences like“the pH was high at8:00 am”,providing the time reference were in the scope of the historic data maintained by the indicator and assuming that the fuzzy membership function was time independent. In Table1is shown the structure of a situation-de?nition;the functions supported were the ramps(ascendant and descendant),that need two arguments,and the trapezium (4arguments)
Five temporal quali?ers(Table1)were de?ned.Now and Ago operate over fuzzy membership values at time points.Sometimes,Always and Generally operate over collections of membership values,for the same fuzzy set,in a time interval.Sometime is true in an interval if the variable have an historical value that is true,it could be considered as a multiple‘or’and its value is the maximum of all the values in the interval.Always is true if all the values in the interval are true,it’s the‘and’extended, and its value is the minimum of the values in the interval.
Generally pretends to express the idea that a logical variable is true most of the time,and it wasn’t so clear how it must be de?ned.The?rst consideration was that if a variable stayed constant in an interval,then“generally”of this variable must be equal to the value of the variable.The second extreme case considered was when all the values of the variable in the interval had values0or1.This is the same situation that if we were working with classical logic.If the variable is always true then“generally”of this variable will be true.If the variable is false more than the half of the time,then we can say that generally of the variable is false.This suggested that a ramp membership function could be used.Then,the chosen formula was:g(x)=max 0,1?s where
x.If s=0.5(its maximum value)then g(x)=max(0,2
3 situation-de?nition→situation‘for’indicator‘is’
((‘ascendant-ramp’|‘descendant-ramp’)
‘(’number‘,’number‘)’
|‘trapezium’‘(’number‘,’number‘,’number‘,’
number‘)’)
temporal-quali?er→‘now’
|temporal-point‘ago’
|(‘sometime’|‘always’|‘generally’)
(‘between’temporal-point‘and’|‘since’)
temporal-point‘ago’
temporal-expression→temporal-quali?er[function]
(functional-expression|indicator‘is’situation) simple-condition→temporal-expression|wait
|subcondition|procedure-invocation
subcondition-de?nition→subcondition‘is’compound-condition
compound-condition→simple-condition
|compound-condition(‘and’|‘or’)compound-condition
|‘not’compound-condition
antecedent→compound-condition
consequent→{action}
rule→antecedent‘implies’consequent
Table1:Grammar
values and it’s applied to every historical point in the interval.The typical example is the“not”operator,in expressions like“generally not(x)”.Moreover,it’s also possible to apply these quali?ers to functions,like“x2>a”,without de?ning an indicator(and keeping its historicals)for x2if we have an indicator(and historicals)for x.
A temporal expression was a simple-condition.They could be combined using con-junction,disjunction and negation to form compound conditions.Nevertheless,not every property of classical logic extend to that formalism.For instance,conjunction isn’t commutative and idempotence no longer holds:if a is a condition,it isn’t always the same as a∧a(i.e.,a is“wait5minutes∧b”).
Moreover,there are other types of simple conditions.A wait condition always is true,but the result is given only after a period of time has elapsed.This was useful to test a sequence of conditions,when some of them were expected to occur in the future. It was also possible to work with subconditions,that were references to compound conditions.As a last resort,another type of simple condition was the invocation of a procedure,that returns a truth value.
A rule had an antecedent and a consequent.The antecedent was a compound condition,while the consequent was a sequence of actions.The possible actions were assignations,waits,rule invocations and procedure calls.The assignations could be deferred;an expression is evaluated and after a period its value was assigned to a variable.
3Graphical Representation
A compound condition could be seen as a pipe diagram,where the simple conditions act as valves.If the condition is true,the valve is open,and if the condition is false the valve is closed.The compound condition is true if there exists a path of open valves from the origin to the destination.The conjunction must be expressed connecting two conditions in serial,and the disjunction connecting the conditions in parallel.Figure1
4
Figure1:Graphical representation example
shows a diagram using this notation.
This representation was chosen because it’s more intuitive,for our users,than the logical gates representation.Moreover,it allows to express temporal issues(sequen-tiality,parallelism).A problem arose with the negation,because it hasn’t an intuitive correspondence in this notation.The selected solution was that the negations are only possible in simple conditions.This wasn’t so problematic because it’s possible to work with subconditions as another type of simple condition,and negate all the subcondition.
The condition editor initially showed two nodes,the initial and the?nal nodes. Also,there were so many buttons as types of simple conditions,that added a node representing a condition.Then,it was possible to edit the simple condition of the node, to place it,and to connect with other nodes.To work with temporal expressions was needed that indicators and situations were de?ned.An example of this de?nition is shown in Fig.2.
This notation was used by the user to introduce conditions,but also showed the result of the last evaluation of a condition.This was useful to give explanations to the user.Although fuzzy logic was used,in the tracing a three-valued(true,false and unknown)logic was employed.A simple condition could be unknown because its evaluation returned an unknown value or because it hadn’t been necessary to evaluate it to obtain the value of the composite condition.Di?erent colours were used to show the three possible situations of a simple condition.The connections between simple conditions were also coloured.When a connection went into a node,the output of this
5 node is the minimum of the value of the input connection and the value of the node. When two input connections are joined,the resulting connection has a value that is the maximum of the values of the input connections.Figure1shows three true simple conditions,one false and one unknown.The global result is true.
4Application and Development
This graphical rule language was conceived to support the development of an application designed to adapt the behaviour of a monitoring and diagnosis system[10],already in use at a factory control room,to the real plant working conditions.Monitoring systems are usually constructed considering a set of hypothesis that could be named nominal conditions.The purpose of this application was to allow the user to specify the operation of the monitoring system when the working conditions were not nominal. The graphical rule language was used by the user to specify what conditions weren’t nominal,and what must be done in these circumstances.Typical actions were to disable and enable elements(modules,alarms...)of the monitoring system.
States were used to describe the working conditions of the factory.An state could have rules to detect its input and its output.Simple conditions and actions were added to deal with states in the antecedent and in the consequent of a graphical rule.Then, the system could detect the input and output of states,although the?nal decision was left to the user.Di?erent colors were used in the states to indicate if the state is established and/or detected.The condition in Fig.1was the input of one of these states.
In order to understand and describe the underlying monitoring system,the experi-ence analysis of KADS[12]was used.Nevertheless,the application wasn’t an expert system,although it could be considered as a tool to develop expert systems.Hence,a most general approach to application development was taken,and UML[4]was used to do the analysis and design in an object oriented way.The application was developed using the Expert Systems Development Tool G2,because the underlying monitoring system was developed with this tool.
5Conclusions
This work has proposed a rule based knowledge representation language emphasising two aspects:its visual nature and a particular ontology.These characteristics seemed to be basic for the intended application domain:decision rules were mainly rules of thumb,main users were non programmers,and uncertainty and properties of temporal series were innate to the domain.
The visual nature of the language tried to tackled the problem of an extremely changing application domain,were the underlying physical layout might change every year and the operation protocol might change quicker.This required that the end user could e?ectively modify the knowledge base.Considering also that the?nal users pro?le was wide,from factory director to control room operator,a visual language with a clear semantic and easy to manipulate was clearly a must.We think that the visual language proposed is a suitable tool in such environment.
Another essential aspect was the ontology,or language primitives available to the end user.We looked for a small number of primitives that could capture the typical reasoning often employed by the control room personal.The developed set included only?ve temporal quali?ers,that also took uncertainty into account.The combination
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of this primitives allowed to express,in a very simple way,highly complex conditions. Although the nature and extend of this ontology requires further research,the end users found them highly natural and expressive.
The developed tool was used to design and implement a rather sophisticated appli-cation that allowed control room personal to adapt on-line a monitoring and diagnosis system to the real factory working conditions.The application detected the set of states that de?ned the factory global performance and adjusted the supervisory system ac-cording to the present situation.More over,the end user could de?ne the conditions to establish the states and the actions to be consequently taken.This was a satisfactory test on the language utility.
Acknowledgements.
This work was partially supported by Sociedad General Azucarera Espa?n ola S.A., SGAE.We are also indebt for the challenge of its development and the great num-ber of ideas that,specially,D.Manuel Bolla′?n,initiated and discussed with us. References
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(一) 假定你是红星中学初三学生李华。你的美国朋友Jim在给你的邮件中提到他对中国新近出现的一种共享单车“mobike”很感兴趣，并请你做个简要介绍。请你给Jim回信，内容包括： 1. 这种单车的使用方法(如：APP查看车辆、扫码开锁等); 2. 这种单车的优势; 3. 你对这种单车的看法。 注意：1. 词数不少于80; 2. 开头和结尾已给出，不计入总词数。 提示词：智能手机smartphone, 二维码the QR code 参考范文 Dear Jim, I’m writing to tell you more about the new form of sharing bike mobike mentioned in your latest letter. It’s very convenient to use if you have a smartphone. What you do is find a nearest mobikethrough the APP, scan the QR code on the bike, and enjoy your trip. Compared to other forms of sharing bike, the greatest advantage of mobike is that you can easily find one and never worry about where to park it. It is becoming a new trend as a means of transportation, which relieves the traffic pressure and does good to the environment as well. Hope to ride a mobike with you in China. Yours, Li Hua (二) 最近很多大城市都投放了共享单车(shared bikes)，比如摩拜单车(Mobike)、Ofo共享单车等。由于它们方便停放，骑车也能起到锻炼身体的作用，作为代步工具很受大家欢迎。但是，各地也出现了很多毁车现象，比如刮掉车上的二维码(QR code)、上私锁等。 你对这种现象怎么看?你对共享单车公司有什么建议吗?写一篇符合逻辑的英语短文，80词左右。 参考词汇：bike-sharing companies 共享单车公司，Mobike 和Ofo 是两家共享单车公司，convenience 方便，register登记 参考范文 The shared bikes like Mobike and Ofo bring great convenience to people. You needn’t lock them by simply using your smart phone. They can take you where the subway and bus don’t go. And they can be left anywhere in public for the next user. However, bad things happen. Some people damage the QR code on the bike, or use their own lock, which causes trouble to other users. In my opinion, it’s difficult to turn these people’s ideas in a short time. Therefore, bike-sharing companies like Mobike and Ofo need to do something. For example, those who damage the bike should pay for their actions. Also, because people use their real name toregister as a user, it’s a good way to connect to one’s personal credit. In the end, what I want to say is to take good care of public services. (三) 共享单车(bicycle sharing)已成为时下最热的话题之一，请你就这一话题写一篇短文。内容须包括三方面：1. 共享单车蓬勃发展，成为社会热潮;2. 共享单车带来便利，但也存在问题;3. 我对解决问题的建议。 参考范文 Bicycle Sharing With the development of technology, bicycle sharing comes into people's lives. It becomes more and more popular and much news reported it. At the same time, we should see that there are some problems caused by bicycle sharing. On one side, bicycle sharing makes it very convenient of people traveling. You can find a bicycle anywhere at any time when you want to go out for a cycling, and the price of one trip is very low. It can save time for people. On the other side, its management is not perfect. Even kids can open the lock and ride the bicycle, there is no doubt that such behavior is very dangerous.
介绍北京的英语作文(2) AsBeijinghasbeenconfirmedhomecityofOlympics2008,the spiritofgreenOlympics,scientificOlympicsandhumanizedOlymp icwillsurelybringmoreandmorechangestoBeijing,promotethed evelopmentofsportsandOlympicsinChinaaswellasintheworld,a ndstrengthenthefriendlycommunicationsbetweenChineseandf oreignpeople. 篇六：Beijing BeijingisthecapitalofPeoplesRepublicofChinaandthenation scentreforpolitics,economyandculture.Itenjoysalongandrichhis tory.Therearenumerousheritagesitesandwonderfulexamplesof ancientarchitecture,suchastheworld-famousGreatWall,theTem pleofHeavenandtheForbiddenCity. Besidessightseeingplaces,therearemanydeliciousfoodsuch asPekingducksandBeijingsnacks.Beijingisreallyagoodplacetotr avel. 篇七：Beijing AsthecaptainofChina，Beijinghasbeenthemostpopularcityofchina。SomoreandmorepeoplewanttovisitBeijing.
3.1中介语理论产生的历史背景 60年代是对比分析的兴盛时期。70年代初开始衰落,反映了一种历史的必然,因为这种理论方法无论在理论上还是实践上都面临着严重的危机。 因此,语言学家们为语言教师勾画了这样一幅图景:首先,语言学家们通过两种语言系统(L1和L2)的对比,为语言教师提供一个详细的菜单。这个菜单包括两种语言的相同点与不同点。然后,语言教师便依据这些不同点来预测学习者的难点,并据此来编写教学大纲和教材。但是后来的教学研究和实践证明,语言学家的许诺仅仅是一幅理想的图画而已。70年代初,对比分析遭到激烈的批评。如果第二语言学习者产生的错误完全可以通过两种语言的对比来预测。由此推论,语言的差异等于学习的难点，学习的难点必然导致语言表达的错误。问题是,语言差异是语言学上的概念,学习的难点则是心理学上的概念。学习的难点无法直接从两种语言差异的程度来推测。教学实践也证明,依据对比分析确认的难点事实上并不完全导致错误的产生。对比分析的理论方法存在的致命弱点,如果归结为一句话,那就是,人们试图用简单的语言学的方法去解决复杂的心理学的问题。语言习得涉及到学习的主体和客体的方方面面,对比分析却仅仅局限于语言系统的对比,忽略了学习者这一主体以及作为学习客体的学习过程。由于对比分析在理论与实践上的危机,人们呼吁一种新的理论的诞生,并要求这种新的理论把目光投向学习的主体和客体。早期的中介语理论正是在这种历史背景下产生的。 3.2中介语的概念 于根元、鲁健骥等是在中国应用语言学领域，最早进行了介绍、评述和研究中介语的意义、特点和研究方法。我们来看他们是怎么界定中介语的。于根元认为，所谓中介语就是介于习得语和目的语之间的独立的语言系统，他是第二语言习得者创造的语言系统。鲁健骥认为，中介语指的是由于学习外语的人在学习过程中对于目的语的规律所做的不正确的归纳与推论而产生的一个语言系统,这个语言系统既不同于学习者的母语,又区别于他所学的目的语。 3.3中介语出现的根源 我们着重重复一下鲁健骥对中介语的定义：中介语指的是由于学习外语的人在学习过程中对于目的语的规律所做的不正确的归纳与推论而产生的一个语言
[标签:标题] 篇一：关于汽车的英语作文 好的 Nowadays, with the rapid improvement of people’s living standards, cars have become an indispensable part of people's lives,so that more and more people have a car of their own, especially in cities. It brings some benefits for us but also causes many problems at the same time. For one thing,there’s no doubt that cars provide much convenience for people to go where they want to quickly and easily. Especially on weekday,driving a car can save a lot of time for us to go to work.When some places are too far away from our home, driving our own car is also convenient, we can go wherever we want. However,for another, too many cars will lead to the pressure of public transport, a series of problems will appear.First of all,it will bring about more air pollution,a large amount of polluted air given off by cars do great harm to our health.What’s more, as the existing roads are not so wide for the increasing number of cars,undoubtedly,traffic jams will become more and more serious. Last but not least, cars also place burden on the public facilities in providing more parking lots. As far as I am concerned,everything has its advantages and disadvantages. It’s high time that effective action must be token to limit the ever growing number of cars, the government should take measures to control the air pollution from the cars. Some roads should be widened and more new roads should be constructed. Only in this way，will people benefit from the popularity of cars. 坏的 Nowadays, with the rapid improvement of people's living standards, cars have become an indispensable part of people's lives,so that more and more people have a car of their own, especially in cities.It brings some benefit for us but also causes many problems at the same time. For one thing,it's no doubt that that cars provide much convenience for people to go where they want to quickly and easily. Especially on weekday,driving a car can save a lot of time for us to go to work.When some places are too far away from our home, driving our own car is also convenient, we can go wherever we want. However,for another, too many cars will lead to the pressure of public transport, a series of problems will appear.First of all,it will bring about more air pollution,a large amount of polluted air given off by cars do great harm to our health .What's more, as the existing roads are not so wide for the increasing number of cars,undoubtedly,traffic jams will become more and more serious. Last but not least, cars also place burden on the public facilities in providing more parking lots. As far as I am concerned,everything has its advantages and disadvantages. It's high time that effective action must be token to limit the ever growing number of cars, the government should take measures to control the air pollution from the cars. Some roads should be widened and more new roads should be constructed. Only in this way,will people benefit from the popularity of cars. 篇二：雅思作文高分范文：私家车的利与弊 智课网IELTS备考资料 雅思作文高分范文：私家车的利与弊
中介语简介中介语理论是二语习得中的一个重要理论，它产生于20世纪70年代初并于80年代初被介绍到我国，对我国的外语教学产生了巨大的推动作用，人们也逐步认识到中介语在外语教学中的积极作用。Selinker在其论文Language Transfer （1969）中首次使用了“interlanguage”一词，并于1972发表了题为Interlanguage的研究论文。Selinker认为，中介语是第二语言学习者独立的语言系统，在结构上处于母语和目的语的中间状态（1972）。 中介语在英语学习中的干扰作用 一、中介语定义及特点 中介语（Interlanguage, 简称IL）一词是英国语言学家Selinker 1969 年首次提出. 现在又被译为过渡语、中间语、中继语、语际语等。它是指学习者在某一段时间内所创建的内在语言体系或学习者在整个学习过程中所构建的相互关联的语言体系。学习者在学习和使用第二语言时，不断接受和理解新的语音、语法知识，在此基础上逐渐形成自己的语言结构。并不断对其进行系统的预测调整，通过归纳和推论产生中介语。中介语的语言系统在结构上处于母语（Native Language）和目的语（Target Language）之间，具有独立性，并兼有两者的特点。综合国内外近来的研究,中介语有如下一些特征: 1．独立性 中介语是一个独立的语言系统，它既不同于母语, 又区别于外语, 也不能单纯的把它地看作外语学习过程中由于受母语的干扰而形成的混合体。中介语有其独特的语言规则，这些规则常常被学习者用来解释外语中固有而不规则的语言现象。 2．阶段性 中介语在逐渐进化的过程中，具有一定的阶段性。它是一个开放的体系，不是固定的一成不变的。这个体系在不断被新知识渗透的同时，修正原有知识，逐渐接近目的语。 3．动态性 在外语学习过程中，学习者的中介语在不断的发展变化。虽然它充满了错误，但由于新的语言规则有及强的扩展能力，它们处于不断的组合和变化中，因此中介语随着学习者的努力和交际需要而不断变化，由简而繁，由低而高，逐渐离开母语而接近目的语。如果我们设在母语与目的语之间的中介语为一个连续体，那么，在某一特定阶段，学习者的中介语可以用连续体上的某一点。中介语越接近目的语，说明学习者的外语水平越高。 4．系统性 中介语在每个阶段都表现出较强的系统性和内部一致性。它也是一个由内部要素构成的系统，就是说它有语音的、词汇的、语法的规则系统，而且自成体系。学习者对中介语的使
介绍北京的英语作文1篇 篇一MyFamily Ilovemyfamily,becauseIhaveahappyfamily. MyfatherisanEnglishteacher.HisnameisJacky.Heisthirty-eight.Helikesplay ingbasketball.What’smymotherjop?Issheateacher?Yes,you’reright!Mymotherisverykindandnice,sheisthirty-seven.Mymotherisalways laboriouswork.Ilovemyparents! OnStaurdayandSunday,Ioftengotothelibraryandplaythepiano,Myfathergot oplaybasketball.Sometimes,wewatchTVandlistentomusicathome. Ilovemyfamily.BecauseI’mveryhappytolivewithmyparentstogether! 篇二MyFamily MyFamily Everyonehasafamily.Weliveinitandfeelverywarm.Therearethreepersonsin myfamily,mymother,fatherandI.Welivetogetherveryhappilyandtherearema nyinterestingstoriesaboutmyfamily. Myfatherisahard-workingman.Heworksasadoctor.Healwaystrieshisbesttoh elpevery,patientandmakepatientscomfortable.Butsonetimesheworkssohard thathecan”trememberthedate.
中介语理论研究与第二语言教学 [摘要]中介语理论是第二语言习得研究领域中的一个认知理论。分析和研究中介语产生的根源和特点有助于了解第二语言习得机制,揭示第二语言习得的发展过程和规律。对提高教学效果有重大意义。[关键词]中介语;特点;教学 第二语言习得研究在近40年间取得了令人瞩目的成就。随着研究的不断深入和发展,人们越来越重视第二语言习得的心理过程。中介语理论把第二语言学习者的语言看作是一个内在的语言行为。因此,中介语的研究对外语教学方法论有着重要的意义。 一、中介语的概念 中介语(interlanguage)，也有人译为"过渡语"或"语际语",指的是第二语言学习者特有的一种目的语系统。是指在第二语言习得过程中,学习者通过一定的学习策略,在目的语输入的基础上所形成的一种既不同于其第一语言也不同于目的语,随着学习的进展向目的语逐渐过渡的动态的语言系统. 中介语理论认为，第二语言学习者在学习过程中所掌握和使用的目的语是一种特定的语言系统，这种语言系统在语音、词汇，语法、文化和交际等方面既不同于自己的第一语言，也不同于目的语，而是一种随着学习的进展向目的语的正确形式逐渐靠拢的动态的语言系统。由于这是一种介乎第一语言和目的语之间的语言系统，所以称之为“中介语”。 与lnterlanguage (中介语)相近的概念最早由Corder在论文《学习者错误的意义》中提出,他把学习者尚未达到的目的语语
言能力的外语能力称为过渡能力( transitional competence)。美国语言学Selinker于1969年在论文《语言迁移》中首先提出中介语假说(interlanguage)的概念。1971年,W. Nemsers在《外语学习者的相似系统》中提出了“approximative system”的概念。1972年Selinker在其著名论文《中介语》中提出的中介语假说, 对“中介语”这一概念进行较详细的阐述,是试图探索第二语言习得者在习得过程中的语言系统和习得规律的假说,在第二语言习得的研究史上有重大意义。从而确立了它在第二语言习得研究中的地位。Selinker指出:“中介语是一个独立的语言系统,它产生于学习者试图掌握第二语言所做的努力。”根据塞格林的定义,中介语既可是指第二语言学习者在学习过程中某一特定阶段中认知目标语的方式和结果的特征系统,即一种特定、具体的中介语言,也可以指反映所有学习者在第二语言习得整个过程中认知发生和发展的特征性系统,即一种普遍、抽象的中介语语言体系interlanguage continuum塞格林还指出中介语本身是一个阶段到过程的双重系统和庞大体系,即母语→中介语→目标语系统中的一个必然成分和过程。在这个系统中二语学习者从母语出发经过中介语到达目标语。并指出要到目标语必须经过中介语,中介语是第二语言认知中的必经之路。 二、中介语的产生 应用语言学领域中产生了对比分析方法(20世纪中期)。它通过对人们的母语以及所要学习的第二语言的语音、语法、词法、
get around/round to: do (something that you have intended to do for a long time.) e.g: I was meaning to see that film but I just never got around to it. 我一直想看那部电影，但始终还是没能去看。 just as well/as well: suggesting that something will be a good thing to do/or that it was luckily that something was done or happened. 正好，幸好，不妨 e.g: “Shall I phone to remind him? ” “That would be just as well.” It was just as well you’re not here. You wouldn’t like the noise. get by (Line 3): be good enough but not very good; manage to live or do things e.g: It is a bit hard for the old couple to get by on a small amount of pension. 如果我们坚持到底，我们就能熬过难关。 We’ll get by if we hold on to the end. get across: be understood Did your speech get across to the students? get away with: run away without being punished The teller had been stealing money from the bankand got away with it. 这个出纳一直在偷银行的钱却能侥幸逃脱。 get through (Line 45): come successfully to the end e.g: We’ve stored enough food and fuel to get through the cold winter. 为了度过寒冬，我们已经储备了足够的食物和燃料。 make it (Line 9) : be successful, fulfill the purpose e.g: Having failed for thousands of times, he eventually made it. 她最后成功地成为了一家大公司的总裁。 She finally made it as a CEO of a big corporation. haul (Line 16) v. transport, as with a truck, cart, etc. e.g: These farmers haul fruits and vegetables to the market on a cart in the early morning every day. v. pull or drag sth. with effort or force e.g: A crane has to be used to haul the car out of the stream. long-overdue (Line 20) adj. Being something that should have occurred much earlier. e.g: Changes to the tax system are long overdue .She feels she’s overdue for promotion. supplement (Line 21) v. add to sth. in order to improve it (followed by with) e.g: 1) Forrest does occasional freelance to supplement his income. 2) The doctor suggested supplementing my diet with vitamins E and A. supplementary adj. additional, auxiliary spray (Line 22): v. force out liquid in small drops upon (followed by with) eg: I’ll have to spray the roses w ith insecticide to get rid of the greenfly. freelance (Line 23) adj. doing particular pieces of work for different organizations rather than working all the time for a single 自由职业者的 e.g: Most of the journalists I know are/work freelance.
汽车的重要性《英语作文》 The automobile has become one of the most important means/ways of transportation in the world since it was invented. The automobile has completely changed the lifestyles of almost all the people in the world. In the past, animals like horses and camels were used for traveling and transporting goods. Automobiles are more comfortable and faster. Automobiles have also made it possible for us to transport large quantities of goods and people at the same time. Besides, the invention of the automobile has provided jobs for millions of people all over the world. 翻译： 汽车已经成为世界上最重要的交通工具之一，因为它是发明的。汽车已经完全改变了世界上几乎所有的人的生活方式。 在过去，像马和骆驼的动物被用来运送货物。汽车更舒适，更快速。汽车也使我们能够在同一时间运送大量货物和人。 此外，汽车的发明为全世界上百万的人提供了工作。
三一文库（https://www.doczj.com/doc/565261929.html,） 〔我想去北京英语作文〕 我想去北京的英语作文如何写？那么，下面是小编给大家整理收集的我想去北京英语作文，供大家阅读参考。 我想去北京英语作文1 I’d like to go to a beautiful place. I think it would be Beijing. Beijing is not only our capital city, but also a famous city with long history and wonderful culture. Beijing is also China’s political and cultural center. There’re many old places of great interest, such as the Great Wall, the Summer Palace, the Forbidden City, the Temple of Heaven, and Tiananmen Square. Once you see Tiananmen Square, you will think of Beijing. It has been the symbol of Beijing since 1949. 我想去北京英语作文2 I went to Beijing more than eight times. Beijing is the capital of China. It’s a big city. I am very familiar with Beijing. It takes an hour and forty minutes from Nantong to Beijing by plane. There are many tall buildings in Beijing. It’s a modern city. My family visited the Great Wall, the Summer
中介语石化现象
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浅谈中介语石化现象 1．引言 外语学习中存在一个普遍现象,绝大多数学习者的外语学习达到了一定程度后,就不再像学习的最初阶段稳步提高,而是处于停滞不前的徘徊状态,很难达到目的语这个理想的终点。1972年Selinker把这个现象定义为中介语的石化 (fossilization),此后相关研究、论著相继问世,中介语石化也成为目前二语和外语教育界研究的热门课题之一。 2．中介语石化现象的定义 中介语的石化概念是Selinker(1972)首先提出的:“石化就是母语的词条、规则和词系统倾向保留在与目的语相关的中介语中,不管学习者的年龄有多大,也不管学习者接受的解释和指导有多少,这种倾向都不会改变。”在外语学习中,学习者的语言是处于一种动态的发展变化状态,中介语是一种介于学习者母语与目的语之间的一个逐渐积累和逐渐完善的过程,整个过程形成一个连续体(continuum) 。其理论假设是,中介语的始点是学习者的母语,然后随着目的语、知识的不断摄人,中介语逐渐向目的语靠拢。外语学习过程就是一种以目的语为标准的不断调整和重组的连续体,是学习者在学习新语言过程中所使用的过渡语言。中介语是第二语言认知中的必经之路。理论上,随着语言习得的逐步发展,中介语会渐渐接近直到达到目的语水平。然而大量实验表明,当学习者达到一定程度后,中介语的某些特征就会趋于停滞状态,很难甚至无法消除,从而形成语言石化。 后来,Selinker (1992) 对石化现象进一步阐释:“语言的石化现象是指外语学习者的中介语的一些语言项目,语法规则和系统性知识趋向与固定下来的状态,年龄的增长和学习量的变化对改变这种固定状态不起作用。”Selinker 认为所有外语学习
汽车英文演讲稿 篇一：汽车英语演讲稿 Good morning everyone ,today, the topic of my lecture（演讲） is “Do you love automobiles（'tmbilz）”. before I start my speech ,I want to ask a question,did there anybody present had seen the movie”the Fast and the Furious['fjrs]”.There are many cars of different styles in the movie,for example ,when you see the movie,you can find roadsters（跑车） just like Porsche（保时捷） GT3,sports utility (通用的）vehicles （车）SUV such as Volkswagen ['f:lks,va:gn]Touareg ['twɑ:reɡ](大众途锐）,even armored cars ,all of them are so powerful and beautiful. When I was a child,I dreamed I can have a car like FORD GT 40,this racing bike（跑车） is amazing and fantastic,but as time goes on ,my hobby is changing,now my favorite car is Jeep Rubicon,this is a car I really want ,it’s dynamic performance（性能） and off-road （越野） performance is top-ranking（一流的） ,which other ordinary SUV is unable to compare; the shape and color of this car is magnificent (华丽的） [mg'nfs()nt],and it’s gear-shift system（齿轮转
小学一年级介绍北京的英语作文 Beijing is an ancient city with a long history. Back in 3000 years ago in Zhou dynasty, Beijing, which was called Ji at the moment, had been named capital of Yan. Thereafter, Liao, Jin, Yuan, Ming and Qing dynasty all made Beijing their capital. Therefore, Beijing was famous for "Capital of a thousand years". The long history leaves Beijing precious cultural treasure. Winding for several kilometers in Beijing area, the Great Wall is the only man-made structure that could been seen in the space. The Summer Palace is a classic composition of ancient royal gardens, and the Forbidden City is the largest royal palaces in the world. Tiantan is where the emperor used to fete their ancestors, and also the soul of Chinese ancient constructions. The four sites above has been confirmed world cultural heritage by UNESCO. However, the best representatives for Beijing are the vanishing Hutongs and square courtyards. Through hundreds of years, they have become symbol of Beijing's life. Tian'anmen square being still brilliant today with cloverleaf junctions and skyscrapers everywhere, the old-timey scene and modern culture are combined to present a brand new visage of Beijing. As Beijing has been confirmed home city of Olympics 2008, the spirit of "green Olympics, scientific Olympics and humanized Olympic" will surely bring more and more changes to Beijing, promote the development of sports and Olympics in China as well as in the world, and strengthen the friendly communications between Chinese and foreign people. 北京是一个有着悠久历史的古城。 早在 3000 年前的周朝,北京,这叫霁,被命 名为首都燕。此后,辽、金、元、明、清都是北京首都。因此,北京著名的一千年 的“资本”。 悠久的历史使北京宝贵的文化瑰宝。绕组在北京地区几公里,长城是唯一的 人造结构,可以在空间。 颐和园是古代皇家园林的经典组合,和故宫是世界上最大 的皇家宫殿。 天坛是皇帝用来祭祀他们的祖先的地方,也是中国古代建筑的灵魂。 上面的四个网站已经确认被联合国教科文组织世界文化遗产。然而,北京最好的 代表是消失的胡同和广场庭院。数百年来,他们已经成为北京的生活的象征。天 安门广场到处都在今天依然灿烂的蝶式路口和摩天大楼的,古色古香的场景和现 代文化相结合,提出一个全新的北京的面貌。 随着北京 2008 年奥运会已被证实的家乡,精神的“绿色奥运、科技奥
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