M. UML Models of Agents in a Multi-Agent E-Commerce System

Introduction to Artificial Intelligence智慧树知到课后章节答案2023年下哈尔滨工程大学哈尔滨工程大学第一章测试1.All life has intelligence The following statements about intelligence arewrong（）A:All life has intelligence B:Bacteria do not have intelligence C:At present,human intelligence is the highest level of nature D:From the perspective of life, intelligence is the basic ability of life to adapt to the natural world答案:Bacteria do not have intelligence2.Which of the following techniques is unsupervised learning in artificialintelligence?（）A:Neural network B:Support vector machine C:Decision tree D:Clustering答案:Clustering3.To which period can the history of the development of artificial intelligencebe traced back?（）A:1970s B:Late 19th century C:Early 21st century D:1950s答案:Late 19th century4.Which of the following fields does not belong to the scope of artificialintelligence application?（）A:Aviation B:Medical C:Agriculture D:Finance答案:Aviation5.The first artificial neuron model in human history was the MP model,proposed by Hebb.（）A:对 B:错答案:错6.Big data will bring considerable value in government public services, medicalservices, retail, manufacturing, and personal location services. （）A:错 B:对答案:对第二章测试1.Which of the following options is not human reason:（）A:Value rationality B:Intellectual rationality C:Methodological rationalityD:Cognitive rationality答案:Intellectual rationality2.When did life begin? （）A:Between 10 billion and 4.5 billion years B:Between 13.8 billion years and10 billion years C:Between 4.5 billion and 3.5 billion years D:Before 13.8billion years答案:Between 4.5 billion and 3.5 billion years3.Which of the following statements is true regarding the philosophicalthinking about artificial intelligence?（）A:Philosophical thinking has hindered the progress of artificial intelligence.B:Philosophical thinking has contributed to the development of artificialintelligence. C:Philosophical thinking is only concerned with the ethicalimplications of artificial intelligence. D:Philosophical thinking has no impact on the development of artificial intelligence.答案:Philosophical thinking has contributed to the development ofartificial intelligence.4.What is the rational nature of artificial intelligence?（）A:The ability to communicate effectively with humans. B:The ability to feel emotions and express creativity. C:The ability to reason and make logicaldeductions. D:The ability to learn from experience and adapt to newsituations.答案:The ability to reason and make logical deductions.5.Which of the following statements is true regarding the rational nature ofartificial intelligence?（）A:The rational nature of artificial intelligence includes emotional intelligence.B:The rational nature of artificial intelligence is limited to logical reasoning.C:The rational nature of artificial intelligence is not important for itsdevelopment. D:The rational nature of artificial intelligence is only concerned with mathematical calculations.答案:The rational nature of artificial intelligence is limited to logicalreasoning.6.Connectionism believes that the basic element of human thinking is symbol,not neuron; Human's cognitive process is a self-organization process ofsymbol operation rather than weight. （）A:对 B:错答案:错第三章测试1.The brain of all organisms can be divided into three primitive parts:forebrain, midbrain and hindbrain. Specifically, the human brain is composed of brainstem, cerebellum and brain (forebrain). （）A:错 B:对答案:对2.The neural connections in the brain are chaotic. （）A:对 B:错答案:错3.The following statement about the left and right half of the brain and itsfunction is wrong （）.A:When dictating questions, the left brain is responsible for logical thinking,and the right brain is responsible for language description. B:The left brain is like a scientist, good at abstract thinking and complex calculation, but lacking rich emotion. C:The right brain is like an artist, creative in music, art andother artistic activities, and rich in emotion D:The left and right hemispheres of the brain have the same shape, but their functions are quite different. They are generally called the left brain and the right brain respectively.答案:When dictating questions, the left brain is responsible for logicalthinking, and the right brain is responsible for language description.4.What is the basic unit of the nervous system?（）A:Neuron B:Gene C:Atom D:Molecule答案:Neuron5.What is the role of the prefrontal cortex in cognitive functions?（）A:It is responsible for sensory processing. B:It is involved in emotionalprocessing. C:It is responsible for higher-level cognitive functions. D:It isinvolved in motor control.答案:It is responsible for higher-level cognitive functions.6.What is the definition of intelligence?（）A:The ability to communicate effectively. B:The ability to perform physicaltasks. C:The ability to acquire and apply knowledge and skills. D:The abilityto regulate emotions.答案:The ability to acquire and apply knowledge and skills.第四章测试1.The forward propagation neural network is based on the mathematicalmodel of neurons and is composed of neurons connected together by specific connection methods. Different artificial neural networks generally havedifferent structures, but the basis is still the mathematical model of neurons.（）A:对 B:错答案:对2.In the perceptron, the weights are adjusted by learning so that the networkcan get the desired output for any input. （）A:对 B:错答案:对3.Convolution neural network is a feedforward neural network, which hasmany advantages and has excellent performance for large image processing.Among the following options, the advantage of convolution neural network is（）.A:Implicit learning avoids explicit feature extraction B:Weight sharingC:Translation invariance D:Strong robustness答案:Implicit learning avoids explicit feature extraction;Weightsharing;Strong robustness4.In a feedforward neural network, information travels in which direction?（）A:Forward B:Both A and B C:None of the above D:Backward答案:Forward5.What is the main feature of a convolutional neural network?（）A:They are used for speech recognition. B:They are used for natural languageprocessing. C:They are used for reinforcement learning. D:They are used forimage recognition.答案:They are used for image recognition.6.Which of the following is a characteristic of deep neural networks?（）A:They require less training data than shallow neural networks. B:They havefewer hidden layers than shallow neural networks. C:They have loweraccuracy than shallow neural networks. D:They are more computationallyexpensive than shallow neural networks.答案:They are more computationally expensive than shallow neuralnetworks.第五章测试1.Machine learning refers to how the computer simulates or realizes humanlearning behavior to obtain new knowledge or skills, and reorganizes the existing knowledge structure to continuously improve its own performance.（）A:对 B:错答案:对2.The best decision sequence of Markov decision process is solved by Bellmanequation, and the value of each state is determined not only by the current state but also by the later state.（）A:对 B:错答案:对3.Alex Net's contributions to this work include: （）.A:Use GPUNVIDIAGTX580 to reduce the training time B:Use the modified linear unit (Re LU) as the nonlinear activation function C:Cover the larger pool to avoid the average effect of average pool D:Use the Dropouttechnology to selectively ignore the single neuron during training to avoid over-fitting the model答案:Use GPUNVIDIAGTX580 to reduce the training time;Use themodified linear unit (Re LU) as the nonlinear activation function;Cover the larger pool to avoid the average effect of average pool;Use theDropout technology to selectively ignore the single neuron duringtraining to avoid over-fitting the model4.In supervised learning, what is the role of the labeled data?（）A:To evaluate the model B:To train the model C:None of the above D:To test the model答案:To train the model5.In reinforcement learning, what is the goal of the agent?（）A:To identify patterns in input data B:To minimize the error between thepredicted and actual output C:To maximize the reward obtained from theenvironment D:To classify input data into different categories答案:To maximize the reward obtained from the environment6.Which of the following is a characteristic of transfer learning?（）A:It can only be used for supervised learning tasks B:It requires a largeamount of labeled data C:It involves transferring knowledge from onedomain to another D:It is only applicable to small-scale problems答案:It involves transferring knowledge from one domain to another第六章测试1.Image segmentation is the technology and process of dividing an image intoseveral specific regions with unique properties and proposing objects ofinterest. In the following statement about image segmentation algorithm, the error is （）.A:Region growth method is to complete the segmentation by calculating the mean vector of the offset. B:Watershed algorithm, MeanShift segmentation,region growth and Ostu threshold segmentation can complete imagesegmentation. C:Watershed algorithm is often used to segment the objectsconnected in the image. D:Otsu threshold segmentation, also known as themaximum between-class difference method, realizes the automatic selection of global threshold T by counting the histogram characteristics of the entire image答案:Region growth method is to complete the segmentation bycalculating the mean vector of the offset.2.Camera calibration is a key step when using machine vision to measureobjects. Its calibration accuracy will directly affect the measurementaccuracy. Among them, camera calibration generally involves the mutualconversion of object point coordinates in several coordinate systems. So,what coordinate systems do you mean by "several coordinate systems" here?（）A:Image coordinate system B:Image plane coordinate system C:Cameracoordinate system D:World coordinate system答案:Image coordinate system;Image plane coordinate system;Camera coordinate system;World coordinate systemmonly used digital image filtering methods:（）.A:bilateral filtering B:median filter C:mean filtering D:Gaussian filter答案:bilateral filtering;median filter;mean filtering;Gaussian filter4.Application areas of digital image processing include:（）A:Industrial inspection B:Biomedical Science C:Scenario simulation D:remote sensing答案:Industrial inspection;Biomedical Science5.Image segmentation is the technology and process of dividing an image intoseveral specific regions with unique properties and proposing objects ofinterest. In the following statement about image segmentation algorithm, the error is ( ).A:Otsu threshold segmentation, also known as the maximum between-class difference method, realizes the automatic selection of global threshold T by counting the histogram characteristics of the entire imageB: Watershed algorithm is often used to segment the objects connected in the image. C:Region growth method is to complete the segmentation bycalculating the mean vector of the offset. D:Watershed algorithm, MeanShift segmentation, region growth and Ostu threshold segmentation can complete image segmentation.答案:Region growth method is to complete the segmentation bycalculating the mean vector of the offset.第七章测试1.Blind search can be applied to many different search problems, but it has notbeen widely used due to its low efficiency.（）A:错 B:对答案:对2.Which of the following search methods uses a FIFO queue （）.A:width-first search B:random search C:depth-first search D:generation-test method答案:width-first search3.What causes the complexity of the semantic network （）.A:There is no recognized formal representation system B:The quantifiernetwork is inadequate C:The means of knowledge representation are diverse D:The relationship between nodes can be linear, nonlinear, or even recursive 答案:The means of knowledge representation are diverse;Therelationship between nodes can be linear, nonlinear, or even recursive4.In the knowledge graph taking Leonardo da Vinci as an example, the entity ofthe character represents a node, and the relationship between the artist and the character represents an edge. Search is the process of finding the actionsequence of an intelligent system.（）A:对 B:错答案:对5.Which of the following statements about common methods of path search iswrong（）A:When using the artificial potential field method, when there are someobstacles in any distance around the target point, it is easy to cause the path to be unreachable B:The A* algorithm occupies too much memory during the search, the search efficiency is reduced, and the optimal result cannot beguaranteed C:The artificial potential field method can quickly search for acollision-free path with strong flexibility D:A* algorithm can solve theshortest path of state space search答案:When using the artificial potential field method, when there aresome obstacles in any distance around the target point, it is easy tocause the path to be unreachable第八章测试1.The language, spoken language, written language, sign language and Pythonlanguage of human communication are all natural languages.（）A:对 B:错答案:错2.The following statement about machine translation is wrong （）.A:The analysis stage of machine translation is mainly lexical analysis andpragmatic analysis B:The essence of machine translation is the discovery and application of bilingual translation laws. C:The four stages of machinetranslation are retrieval, analysis, conversion and generation. D:At present,natural language machine translation generally takes sentences as thetranslation unit.答案:The analysis stage of machine translation is mainly lexical analysis and pragmatic analysis3.Which of the following fields does machine translation belong to? （）A:Expert system B:Machine learning C:Human sensory simulation D:Natural language system答案:Natural language system4.The following statements about language are wrong: （）。

Social Patterns for Designing Multiagent SystemsT.Tung Do Manuel Kolp Alain Pirotte Information Systems Research Unit,Catholic University of Louvain, 1,Place de Doyens,1348Louvain-La-Neuve,BelgiumE-mail:{do,kolp,pirotte}@isys.ucl.ac.beAbstractMulti-Agent Systems(MAS)architectures now appear to be more appropriate than traditional ones for building latest generation software that is typically concurrent,dis-tributed,and dynamic.Since the fundamental concepts of multi-agent systems are social and intentional,rather than object,functional or implementation-oriented,the design of MAS architectures should be eased by using what we call social patterns rather than object-oriented design patterns. Social patterns are idioms inspired by social and intentional characteristics used to design the details of a system archi-tecture.The paper presents a framework called SK WY RL used to gain insight into social patterns and help to conduct the design of a MAS architecture in terms of these newly proposed idioms.We define the Booking social pattern,to illustrate the modeling dimensions of SK WY RL.A frame-work for code generation is also presented.1.IntroductionThe characteristics and expectations in new areas of in-formation technology,like e-business,knowledge manage-ment,peer-to-peer computing,or web services,are deeply modifying software engineering.Most of the systems de-signed for those areas are now concurrent and distributed. They tend to be open and dynamic in the sense that they exist in a changing organizational and operational environ-ment where new components can be added,modified,or removed at any time.To address those new needs,we advocate the use of mul-tiagent system(MAS)architectures that appear to be more flexible,modular,and robust than traditional ones.A MAS could be seen as a social organization of autonomous soft-ware entities(agents)that canflexibly achieve agreed-upon intentions by interacting with one another.MAS do allow dynamic and evolving structures which can change at run-time to benefit from the capabilities of new system entities or replace obsolete ones.An important technique that helps in the construction and documentation of architectures is the reuse of design experience and knowledge.Design patterns have become an attractive approach to do that(See e.g.[6]).Patterns de-scribe a problem commonly found in software design con-figurations and prescribe aflexible solution for the prob-lem,so as to ease the reuse of that solution.This solution is repeatedly applied from one design to another,produc-ing design structures that look quite similar across different applications.A social organization-based MAS development can help matching the system architecture with its operational envi-ronment.Taking real-world social behaviors as a metaphor together with considering the importance of design patterns for building MAS architectures,this paper focuses on social patterns.We define social patterns as design idioms based on social and intentional behavior for constructing MAS. By that,we mean that MAS are composed of autonomous intentional agents that socially interact and coordinate to achieve their intentions as in an organizational society.This work continues the research in progress in the Tro-pos project,whose aim is to construct and validate a soft-ware development methodology for agent-based software systems.The Tropos methodology[3]adopts ideas from MAS technologies and concepts from requirements engi-neering,where agents and goals have been used heavily for organizational modeling.The key premise of the project is that agents and goals can be used as fundamental concepts for analysis and design during all the phases of the software development life cycle,and not just for requirements analy-sis.In[10]we have overviewed a social ontology for Tro-pos to consider software as(built of)social and intentional structures all along the development life cycle.The on-tology considers organizational styles for architectural de-sign–where the global system architecture is defined in terms of subsystems,interconnected through data,control and other dependencies–and social patterns for detailed design–where behavior of each architectural component is defined in further anizational architectural styles for Tropos have been further detailed in[9].The present paper details the notion of social patterns. It focuses on the conceptualization of a framework called SK WY RL1to model these newly proposed idioms accord-ing tofive complementary dimensions:social,intentional, structural,communicational,and dynamic.We propose to apply the framework to help design the detail of MAS ar-chitectures.As an illustration,the paper defines and studies a social pattern called Booking.We also introduce the gen-eration of code from given social patterns into JACK[8],a JA V A agent-oriented development environment.The paper is organized as follows.Section2intro-duces some major social patterns.Section3proposes the SK WY RL framework,illustrates it through the Booking pattern and overviews the code generation.Finally,Section 4summarizes the results and points to further work.2.Social PatternsConsiderable work has been done in software engineer-ing for defining software patterns(see e.g.,[6]).Unfor-tunately,little emphasis has been put on social and inten-tional aspects.Moreover,the proposals of agent patterns that address these aspects(see e.g.,[1,4])are not intended to be used at a design level,but rather during implementa-tion when low-level issues like agent communication,infor-mation gathering,or connection setup are addressed.In the following,we present patterns focusing on social and intentional aspects that are recurrent in multi-agent and cooperative systems.In particular,the structures are in-spired by the federated patterns introduced in[7,9].We have classified them in two categories.The Peer patterns describe direct interactions between negotiating agents.The Mediation patterns feature intermediate agents that help other agents to obtain some agreement about an exchange of services.Some of the patterns are depicted byfigures that reflect their projections on a particular aspect(called modeling di-mension).The meaning of these modeling dimensions is detailed in Section3.2.1.Peer PatternsThe Booking pattern involves a client and a number of service providers.The client issues a request to book some resource from a service provider.The service provider can accept the request,deny it,or propose to place the client on a waiting list,until the requested resource becomes available when some other client cancels a reservation.The Call-For-Proposal pattern involves an initiator and a number of participants.The initiator issues a call for1Socio-Intentional ArChitecture for Knowledge Systems and Require-ments ELicitation(http://www.isys.ucl.ac.be/skwyrl/)proposals for a service to all participants and then accepts ”proposals”that offer the service for a specified”cost”. The initiator selects one participant who performs the contracted work and informs the initiator upon completion. Figure1shows the social and communicational dimensions of thispattern.Figure1.Call-For-Proposal Pattern The Bidding pattern involves an initiator and a number of participants.The initiator organizes and leads the bidding process.He publishes the bid to the participants and receives various proposals.At every iteration,the initiator can accept an offer,raise the bid,or cancel the process.2.2.Mediation PatternsIn the Monitor pattern,subscribers register for receiv-ing,from a monitor agent,notifications of changes of state in some subjects of their interest.The monitor accepts subscriptions,requests information from the subjects of interest,and alerts subscribers accordingly.In the Broker pattern,the broker agent is an arbiter and intermediary that requests services from a provider to satisfy the request of a consumer.Figure2models the social and communicational dimensions of thispattern.Figure2.BrokerIn the Matchmaker pattern,a matchmaker agent locates a provider for a given service requested by a consumer,and then lets the consumer interact directly with the provider, unlike brokers,who handle all interactions between con-sumers and providers.In the Mediator pattern,a mediator agent coordinates the cooperation of performer agents to satisfy the request of an initiator agent.While a matchmaker simply matches providers with consumers,a mediator encapsulates interac-tions and maintains models of the capabilities of initiators and performers over time.In the Embassy pattern,an embassy agent routes a service requested by an external agent to a local agent. If the request is granted,the external agent can submit messages to the embassy for translation in accordance with a standard ontology.Translated messages are forwarded to the requested local agent and the result of the query is passed back out through the embassy to the external agent.The Wrapper pattern incorporates a legacy system into a multi-agent system.A wrapper agent interfaces system agents with the legacy system by acting as a translator.This ensures that communication protocols are respected and the legacy system remains decoupled from the rest of the agent system.3.SK WY RL:A Social Patterns FrameworkThis section describes SK WY RL,a conceptual frame-work,based onfive complementary modeling dimensions, to introspect social patterns.Each dimension reflects a par-ticular aspect of a MAS architecture,as follows.•The social dimension identifies the relevant agents in the system and their intentional interdependencies.•The intentional dimension identifies and formalizes the services provided by agents to realize the intentions identified by the social dimension,independently of the plans that implement those services.This dimen-sion answers the question:”What does each service do?”•The structural dimension operationalizes the services identified by the intentional dimension in terms of agent-oriented concepts like beliefs,events,plans,and their relationships.This dimension answers the ques-tion:”How is each service operationalized?”•The communicational dimension models the temporal exchange of events between agents.•The dynamic dimension models the synchronization mechanisms between events and plans.The social and the intentional dimensions are specific to MAS.The last three dimensions(structural,communica-tional,and dynamic)of the architecture are also relevant for traditional(non-agent)systems,but we have adapted and extended them with agent-oriented concepts.The rest of the section details the dimensions.Each of them will be illustrated through the Booking pattern.3.1.Social DimensionThe social dimension specifies a number of agents inter-acting with each other and their intentional interdependen-cies using the i*social model[13].Agents are represented as circles and their intentional dependencies as ovals.An agent(the depender)depends upon another agent(the de-pendee)for an intention to be fulfilled(the dependum).To formalize the intentional interdependencies,we use Formal Tropos[5],a language that provides a textual no-tation for i*models and allows to describe dynamic con-straints among the elements of the specification in afirst-order temporallogic.Figure3.Social Diagram-Booking Figure3shows the social-dimension diagram for the Booking pattern.The Client depends on the Service Provider to provide resources and cancel existing reserva-tions.A provide resource intentional dependency could be defined in Formal Tropos as follows.Intention Provide ResourceMode:AchieveDepender:Client clDependee:Service ProviderFulfillment:(∀rr:ReservationRequest)request(cl,rr)→(∃sp:ServiceP rovider,rt:ResourceT ype)provide(sp,rt)∧ofT ype(rr,rt)∧♦assigned(sp,rt,rr.quantity,cl)[The Client cl wishes that,for his reservation request rr,some timein the future there will exist a Service Provider sp able to providert the resource type of rr–represented by ofType(rr,rt)–and thenumber of rt units–represented by rr.quantity–will be assignedhim.ReservationRequest and ResourceType are two entities thatstore information about the client reservation request and the typeof resource that the Service Provider can provide.]3.2.Intentional DimensionWhile the social dimension focuses on interdependen-cies between agents,the intentional view aims to model the rationale of an agent.In other words,it is concerned with the identification of services possessed by agents and avail-able to achieve the intentions identified by the social dimen-sion.Each service belongs to one agent.Service definitions can be formalized as intentions that describe the fulfillment condition of the service.The collection of services of an agent defines its behavior.Table1lists several services of the Booking pattern with an informal definition.Service Name Informal Definition Agent FindPotentialSP Find service providers that can Clientprovide the requested resourceFindSP Find service providers that can Clientprovide the requested resourceby the client’s own knowledge FindSPWithMM Find service providers that can Clientprovide the requested resourcewith the help of a matchmaker SendReservation Send a booking request to the Client Request potential service providersQueryResource Query the database for information Service Availability about the availability of the Providerrequested resourceSendReservation Send answer to client Service Decision Provider RecordSPRefusal Record a negative answer from Clientthe service providerRecordWLProposal Record a proposal for a Clientwaiting list optionRecordOffer Record an offer for a resource Client RecordSPRefusal Record a negative answer ServiceProvider Table1.Some Services of the Booking PatternThe FindPotentialSP service allows a client tofind service providers that can provide a requested resource.This service is fulfilled either by the FindSP or the FindSPWithMM services(the clientfinds po-tential service providers based on its own knowl-edge or via a matchmaker).The request is then sent to the potential service providers through the SendReservationRequest service.When re-ceiving such a request,a service provider queries its database using the QueryResourceAvailability service and then answers the client through the SendReservationDecision service.Three al-ternative answers are possible:(1)the resource cannot be supplied;(2)the resource can be supplied but not for the moment:a waiting list option is proposed to the client;(3)the resource can be provided and an offer is made to the client.The client processes these answers with services RecordSPRefusal,RecordWLProposal, and RecordOffer,respectively.The service provider also records its negative answers,for later reminiscence, through its RecordSPRefusal service.Services can be formalized in Formal Tropos as illus-trated below for the FindPotentialSP service.Service FindPotentialSPType:IntentionMode:AchieveAgent:Client clFulfillment:(∀rr:ReservationRequest)request(cl,rr)→(∃sp:ServiceP rovider,rt:ResourceT ype)(provide(sp,rt)∧ofT ype(rr,rt)∧♦known(cl,sp)[FindPotentialSP is fulfilled when the client has found(knownpredicate)some ServiceProvider(s)that is(are)able to perform(provide predicate)the reservation requested.]3.3.Structural DimensionUnlike the intentional dimension that answers the ques-tion”What does each service do?”,the structural dimen-sion answers the question”How is each service operational-ized?”.Services will be operationalized as plans,that is, sequences of actions.As already said,a MAS is a social organization of in-tentional autonomous software entities called agents.The knowledge an agent has(about itself or about the environ-ment to which it belongs)is stored in its beliefs.An agent can act in respond to the events it handles through its plans.A plan in turn,is used by the agent to read or modify its be-liefs and send(or post)events to other agents(or to itself).The structural dimension is modeled using a UML style class diagram extended for MAS engineering.The required agent concepts extending the class diagram model are defined below.The structural dimension of the Booking pattern illustrates them.3.3.1Structural conceptsFigure4depicts the concepts and their relationships, needed to build the structural dimension.Each concept defines a common template for classes of concrete MAS (for example,Agent in Figure4is a template for agent class ServiceProvider of Figure5).A Belief describes the knowledge that an agent has about itself and its environment.A belief is a tuple composed of a key and valuefields.Events describe stimuli,emitted by agents or automati-cally generated,in response to which the agents must takeaction.As shown by Figure4,the structure of an eventis composed of three parts:declaration of the attributes of the event,declaration of the methods to create the event, declaration of the beliefs and the condition used for an au-tomatic event.The third part only appears for automatic events.Events can be described along three dimensions:•External/Internal event:event that the agent sends to other agents/event that the agent posts to itself.This property is captured by the scope attribute.•Normal/BDI event:An agent has some alternative plans in response to a BDI event and only one plan in response to a normal event.Whenever an event oc-curs,the agent initiates a plan to handle it.If the plan execution fails and if the event is a normal event then the event is said to have failed.If the event is a BDI event,a set of plans can be selected for execution and these are attempted in turn,in order to try to achieve successful plan execution.If all the plans in the set of selected plans have failed,the event is also said to have failed.The event type is captured by the type attribute.•Automatic/Not Automatic event:an automatic event is automatically created when certain belief states arise.The create when statement specifies the logical condition which must arise for the event to be automatically created.The states of the beliefs that are defined by use belief is monitored to determine when to automatically create an event.A Plan describes a sequence of actions that an agent can take when an event occurs.As shown by Figure4,plans are structured in three parts:the Event part,the Belief part, and the Method part.The Event part declares events that the plan handles(i.e.,events that trigger the execution of the plan)and events that the plan produces.The latter can be either posted(i.e.,sent by an agent only to itself)or sent(i.e.,sent to other agents).The Belief part declares beliefs that the plan reads and those that it modifies. The Method part describes the plan itself,that is,the actions performed when the plan is executed.The Agent concept defines the behavior of an agent,in-cluding the type of events it posts and sends,the plans it uses to respond to the events it handles,and the beliefs it has as its knowledge.The agent structure is composed offive parts:declara-tion of its attribute,declaration of events it posts(or sends) explicitly(i.e.,without using its plans),declaration of its plans,declaration of its beliefs and declaration of its meth-ods.The beliefs of an agent can be of type private,agent, or global depending on how the agent can access beliefs0 . .*0 . .*0 .. *0 . .*10 . .*0 .. *110 .. *0 . .*1 .. *0 .. *0 . .*Agent EventPlanBeliefAttributeEventPlanBeliefMethodAttributeCreating MethodCreated AutomaticallyEventUsed BeliefMethodAttribut<plan>has beliefhandles <belief><belief><belief><logical condition><belief>posts / sendsplanusesusesbeliefuses beliefposts /sends<event><event><event><belief><belief> keyvalueprivate beliefagent beliefglobal beliefpostsend<event><event>Scope : <"Internal"> | <"External">Type : <"Normal"> | <"BDI">create whenuse beliefhandlepostsendreadmodifymain() {}FieldType FieldNameFieldType FieldNameCreatingMethodName (param. list) {}Figure4.Structural Diagram Templatedata.A private access means that the agent can read and modify independent of all other agents,even those of the same agent class;an agent access means that the agent has shared read-only access to the belief,but only with other agents of the same class;a global access means that the agent has shared read-only access to the belief with all other agents.3.3.2Booking Pattern Structural ModelAs an example,Figure5depicts the Booking pattern com-ponents.Due to lack of space,each construct described ear-lier is illustrated only through one Booking pattern com-ponent.Each of these components can be considered an instantiation of the(corresponding)template defined in the previous section.ServiceProvider is one of the two agents composing the Booking pattern.It uses plans such as QueryResourceAvailability, SendReservationDecision,etc.The plan name is also the name of the service that it operationalizes.The global belief ResourceType is used to store the resource type and its descriptions(e.g.,for an air ticket booking system,the resource type could be economic/ first class/business class;for a hotel room booking system the resource type could be single room /double room/...).This belief is declared as global since it will be used by both the client agent and the service provider agent.The other beliefs are declared as private since the service provider is the only agent that can manipulate them.WLDeadLineArisedAttribute// String rRCode // String clientID Type : « Normal » Scope : « Internal » // Date wLDeadLineCreating Method// createEvnt (String rRCode,// String ClientID, Date wLDeadLine)Created Automaticallycreate whencurrent time =AcceptedWLProposal.wLDeadLine use beliefAcceptedWLProposalAttributeEvent PlanString NameQueryResourceAvailability RecordSPRefusal SendReservationDecision ........ServiceProviderBeliefprivate belief ResourceInfoReservationRequest ........global belief ResourceTypeMethod// Constructorpublic ServiceProvider (String sPName)// load data to the beliefs of // the services providerpublic void loadBK_SP () ........value// String clientID Attributkey// String rRCode // Date wLDeadLineAcceptedWLProposalEventhandlepostsendAvailabilityQueried SPRefusedInternal SPRefusedExternal SendReservationDecisionSPWLProposedSPResourceProposed modifyReservationRequestMethodUsed Beliefmain(){// save reservation request to // ServiceProvider’s belief // post and send events upon the// resource availability and the price // provided by client}Figure 5.Structural Diagram -BookingThe constructor method allows to give a name to a service provider agent when created.This method may call other methods,for example loadBK SP(),to initiate agent beliefs data.SendReservationDecision is one of the Booking pattern plans the service provider uses to answer the client:the SPRefusedExternal event is sent when the answer is negative,SPResourceProposal when there is some resource available for the client,or SPWLProposal (Service Provider Waiting List Proposal)when the service provider is able to provide the type of resource asked by the client but not at the moment of the request since all these kind of resources are reserved.This plan is executed when the AvailabilityQueried event (containing the information about the availability of the resource type required by the client)occurs.This plan also modifies ReservationRequest ,the service provider’s belief storing the client’s reservation request before the service provider sends (or posts)his answer.AcceptedWLProposal is one of the service provider’s beliefs used to store the client’s accepted waiting list proposal.The reservation request code rRCode and the clientID form the belief key.The reservationInfoCode attribute that contains the correspondent code of the resource type requested by the client,and the wLDeadLine that contains the time-out before which the service provider must send a resource not available message to the client if no resource is proposed,are declared as value fields.WLDeadlineArised is an event that is posted automatically whenever the time-out wLDeadLine (of the AcceptedWLProposal belief)is reached.It will then invoke a plan to inform the client that the resource is not available.munication DimensionAgents interact with each other by exchanging events.The communicational dimension models,in a temporal manner,events exchanged in the system.We adopt the se-quence diagram model proposed in AUML [2]and extend it:agent name/Role:pattern name expresses the role (pat-tern name )of the agent (agent name )in the pattern;the ar-rows are labeled with the name of the exchangedevents.Figure munication Diagram -BookingFigure6shows the sequence diagram for our Book-ing pattern.The client(customer1)sends a reser-vation request(ReservationRequestSent)contain-ing the characteristics(place,room,etc.)of the re-source it wishes to obtain from service providers.The service provider may alternatively answer with a de-nial(SPRefusedExternal),a waiting list proposal (SPWLProposed)or an approval,i.e,a resource proposal when there exists such a resource that satisfies the charac-teristics the client sent.In the case of a waiting list proposal (SPWLProposed),when the client accepts it (AcceptedWLProposalSent),it sends a wait-ing list time-out(wLDeadLine)to the service provider.Before reaching the time-out,the service provider must send a refusal to the client,in the case it does notfind an available slot in the waiting list (ResourceNotAvailableMessageSent),or pro-pose a resource to the client.In the later case,the interaction continues as in the case that the resource proposal is sent to the client.A resource that is not available becomes available when some client(customer2in Figure6)cancels its reserva-tion.3.5.Dynamic DimensionAs described earlier,a plan can be invoked by an event that it handles and create new events.Relationships be-tween plans and events can rapidly become complex.To cope with this problem,we propose to model the synchro-nization and the relationships between plans and events with activity diagrams extended for agent-oriented systems. These diagrams specify the events that are created in paral-lel,the conditions under which an event is created,which plan handles which event,and so on.An internal event is represented by a dashed arrow and an external event by a solid arrow.As mentioned earlier,a BDI event may be handled by alternative plans.They are enclosed in a round-corner box.A plan is represented by a lozenge shape.Synchronization and branching are repre-sented as usual.Four activity diagrams actually model the dynamic di-mension of the Booking pattern;due to lack of space,we only present one,depicted by Figure7.It models theflow of control from the emission of a reservation request to the re-ception by the client of the answer from the service provider (refusal,resource proposal,or waiting list proposal).Two swimlanes,one for each agent of the Booking pattern,com-pose the diagram.MaxPrice stores the maximum value that the client can afford to obtain a resource unit;quantity stores the number of resource units the client wishes to book;reservedQuantity and maxQuantity respectively store the actual quantity of resource units that are reserved and the maximum number of resource units that the service provider can provide.At a lower level,each plan could also be modeled by an activity diagram for further detail if necessary.Figure7.Dynamic Diagram-Booking3.6.Code GenerationThe main motivation behind design patterns is the possi-bility of reusing them during system detailed design and im-plementation.Numerous CASE tools such as Rational Rose [11]and Together[12]have then included code generators for object-oriented design patterns.Programmers identify and parameterize,during system detailed design,the pat-terns that they use in their applications.The code skeleton for the patterns is then automatically generated.The work of programmers is made easier,as they only have to add the application code too specific to be generated.SK WY RL proposes a code generator for the social pat-terns introduced in Section2.Figure8shows the main win-dow of the tool.It is developed with and produces code for JACK[8],an agent-oriented development environment built on top of Java.JACK extends Java with specific capabili-ties to implement agent behaviors.On a conceptual point of view,the relationship of JACK to Java is analogous to that between C++and C.On a technical point of view,JACK source code isfirst compiled into regular Java code before being executed.With the code generator of SK WY RL,the programmer first chooses a social pattern to use and selects an appli-cation domain on which the pattern will be applied.For instance,for the Booking pattern,common domains such as AirlineTicket and HotelRoom have been already。

正确答案：A、B 你选对了Quizzes for Chapter 11 单选(1 分)图灵测试旨在给予哪一种令人满意的操作定义得分/ 5 多选(1 分)选择下列计算机系统中属于人工智能的实例得分/总分总分A. W eb搜索引擎A. 人类思考B.超市条形码扫描器B. 人工智能C.声控电话菜单该题无法得分/1.00C.机器智能 1.00/1.00D.智能个人助理该题无法得分/1.00正确答案：A、D 你错选为C、DD.机器动作正确答案： C 你选对了6 多选(1 分)选择下列哪些是人工智能的研究领域得分/总分2 多选(1 分)选择以下关于人工智能概念的正确表述得分/总分A.人脸识别0.33/1.00A. 人工智能旨在创造智能机器该题无法得分/1.00B.专家系统0.33/1.00B. 人工智能是研究和构建在给定环境下表现良好的智能体程序该题无法得分/1.00C.图像理解C.人工智能将其定义为人类智能体的研究该题无法D.分布式计算得分/1.00正确答案：A、B、C 你错选为A、BD.人工智能是为了开发一类计算机使之能够完成通7 多选(1 分)考察人工智能(AI) 的一些应用，去发现目前下列哪些任务可以通过AI 来解决得分/总分常由人类所能做的事该题无法得分/1.00正确答案：A、B、D 你错选为A、B、C、DA.以竞技水平玩德州扑克游戏0.33/1.003 多选(1 分)如下学科哪些是人工智能的基础？得分/总分B.打一场像样的乒乓球比赛A. 经济学0.25/1.00C.在Web 上购买一周的食品杂货0.33/1.00B. 哲学0.25/1.00D.在市场上购买一周的食品杂货C.心理学0.25/1.00正确答案：A、B、C 你错选为A、CD.数学0.25/1.008 填空(1 分)理性指的是一个系统的属性，即在_________的环境下正确答案：A、B、C、D 你选对了做正确的事。

得分/总分正确答案：已知4 多选(1 分)下列陈述中哪些是描述强AI (通用AI )的正确答案？得1 单选(1 分)图灵测试旨在给予哪一种令人满意的操作定义得分/ 分/总分总分A. 指的是一种机器，具有将智能应用于任何问题的A.人类思考能力0.50/1.00B.人工智能B. 是经过适当编程的具有正确输入和输出的计算机，因此有与人类同样判断力的头脑0.50/1.00C.机器智能 1.00/1.00C.指的是一种机器，仅针对一个具体问题D.机器动作正确答案： C 你选对了D.其定义为无知觉的计算机智能，或专注于一个狭2 多选(1 分)选择以下关于人工智能概念的正确表述得分/总分窄任务的AIA. 人工智能旨在创造智能机器该题无法得分/1.00B.专家系统0.33/1.00B. 人工智能是研究和构建在给定环境下表现良好的C.图像理解智能体程序该题无法得分/1.00D.分布式计算C.人工智能将其定义为人类智能体的研究该题无法正确答案：A、B、C 你错选为A、B得分/1.00 7 多选(1 分)考察人工智能(AI) 的一些应用，去发现目前下列哪些任务可以通过AI 来解决得分/总分D.人工智能是为了开发一类计算机使之能够完成通A.以竞技水平玩德州扑克游戏0.33/1.00常由人类所能做的事该题无法得分/1.00正确答案：A、B、D 你错选为A、B、C、DB.打一场像样的乒乓球比赛3 多选(1 分)如下学科哪些是人工智能的基础？得分/总分C.在Web 上购买一周的食品杂货0.33/1.00A. 经济学0.25/1.00D.在市场上购买一周的食品杂货B. 哲学0.25/1.00正确答案：A、B、C 你错选为A、CC.心理学0.25/1.008 填空(1 分)理性指的是一个系统的属性，即在_________的环境下D.数学0.25/1.00 做正确的事。

A Multi-Agent Framework for Execution of Complex ApplicationsAlexandru Cicortas, Victoria IordanComputer Science DepartmentFaculty of Mathematics and Computer ScienceUniversity of the West Timisoarae-mail: cico@info.uvt.ro, iordan@info.uvt.roAbstract: Complex applications execution needs a lot of conditions starting with hardware and software resources until the task sequencing and verifying the results of the execution. The needed resources can be found locally or on the Web and Grid. For an efficient usage the needed resources application and the effective resources found must be described in an appropriate and way and we propose the XML. The matching between the resources of the application and the Web/Grid resources is done in our proposal by the agents. As a new approach in the last years is the Service Oriented Architecture (SOA) that is developed as an efficient solution. The services are furnished by the providers and these are used by the clients in some specific conditions. The realization of the SOA technology presents a real opportunity to improve effectiveness. On the Web and Grid we dispose for services and these can be used in a given contest. SOA provides the application of well-founded concepts that exploits the ability of modern system resources to collaborate, independent of location across heterogeneous technologies.Keywords: multi-agent systems, grid, resource management, complex systems design, service oriented architecture.1 IntroductionReal world systems grow in complexity. The execution of complex applications implies adequate tools and also support for execution. The Web and Grid offer an efficient way for executing the requirements of companies that must interact in a very complex manner.The grid model, with its use of resources tends to be heterogeneous and distributed across multiple management domains. For example, in a grid environment shared resources must remain accessible, not but that the hardware configuration is dynamic, the resources can be available in a time instant, but in an another time instant these can disappear. In the grid key infrastructure services must be available, and virtual organizations must be maintained. It must also bepossible to detect report and deal with faults that may occur in any of the member domains.Effective system management is only possible if resources are manageable, and if tools are available to manage them. However, these tools tend to operate independently and to use proprietary interfaces and protocols to manage a limited set of resources, making it difficult for an organization to build an efficient, well-integrated management system. In order to allow the development of manageability standards that will enable conforming management tools to manage conforming resources in a uniform manner, and to interoperate with each other. In turn this will enable system administrators to choose their management tools and suppliers in the knowledge that, regardless of their origin, the tools can work cooperatively in an integrated management environment.As stated in [15] the resource management includes:•reservation, brokering and scheduling;•installation, deployment and provisioning;•metering;•aggregation (service groups, WSDM collections, etc.);•VO management;•security management;•monitoring (performance, availability, etc.);•control (start, stop, etc.);•problem determination and fault management.Some of other major problems are to use and discovery the resources.Beside resources, the grid offers also services. These services can be simple services or complex ones and use resources. Like resources the services must be represented in an adequate manner in order to be found and used. In many grid organizations the registers are used in order to furnish the resources and services that can be used or invoked.The problem of execution of complex applications that must be solved in an efficient manner using the grid requires a lot of complex tools. Some of aspects of the problem concern:•formulating the problem that is proposed to be solved;•expressing an adequate decomposition of the application in the tasks;•for every task to express the hardware and software resources that are needed;•giving an appropriate expression of the task sequencing and conditioning;•defining the services that will be invoked;•searching and discovering on the grid for the appropriate resources and services;•if there is the case to allow the migration of the software agents (SA) on the grid and also to install the needed (adequate) software;•defining the data that must be partially hosted for the future tasks (temporary storage of partial data or needed data for recovering in the case of failure);•defining the recoveries when some failure occurs.The execution of such grid application can be expressed in terms of workflow. This subject will be detailed in another paper. Concerning the workflow of the complex application on the grid, there are many works like [4], [16] that describe how the workflow must be designed.There exist a lot of works that threat partially or totally such a kind of approach in the grid context. The GLOBUS [11] UNICORE [18] and the works done for the Fraunhofer Resource Grid [10] solve in some partially sense the above requirements.Being in many cases a complex problem the jobs execution needs to overcome some of the exception situations as rollbacks and resuming in the incidents. In a framework it implies some additional activities like:•localization of the failed task;•analysis of the task execution;•the resuming of the task from an intermediary point if there exists a such point;•resuming the data bases implied in the same node or other nodes.There exist many frameworks that allow to the application designers to dispose for:•tools, standards and languages to define express and use the information concerning the evolution of the application during its execution;•an adequate Grid framework that allows to:o explore and find the grid resources;o establish in the grid context, the conditions for the task execution and in the failure cases the conditions for resuming the task (like thetemporary storage of data);o launching and controlling the task execution;o in order to obtain the desired results the framework must allow the rollbacks.We propose also a framework.Multi-agent systems are used in many domains and their strength allows developing complex systems. The agent abilities i.e., self adaptation, learning from own experience or from collectivity experience, the communication and collaboration are very expressive tools in order to reach the system goals.The following concepts [20] are closely related:•Choreography describes required patterns of interaction among services and templates for sequences (or more structures) of interactions;•Orchestration describes the ways in which business processes are constructed from Web services and other business processes, and how these processes interact;•Workflow is a pattern of business process interaction, not necessarily corresponding to a fixed set of business processes. All such interactions may be between services residing within a single data center or across a range of different platforms and implementations anywhere.The XML is used for expressing the appropriate information that can be processed using various platforms in most recent initiatives concerning the usage of adequate standards that are applied in many domains. In many of real projects the XML [22] is an adequate mean in order to allow expressing the needs and it in platform independent. Based on the previous experience in the following the XML will be used.The paper proposes:• a framework that uses the XML that allows to express and furnish the required information to the designer. The information concerns the grid its resources, its services, its location and also the details of the application concerning its decomposition in tasks, the sequencing of the tasks and consequently the resources and services needed for tasks execution;• a multi-agent system as a solution for solving such kind of problems;• a workflow model for the execution of the applications in the grid context.It will be the subject of another work and papers due the particularities of the workflow.The paper is structured as follows. The information used is shortly revised in the next Section. The third Section presents the concepts and tools used for modeling. The fourth Section, propose the multi-agent system as a possible solution. In Section 5 the framework is sketched and some details are given. The last Section contains some conclusions and future works.2 The Information for the Grid ResourcesSome of the resource Grid components usually are not described in the necessary detailed form in order that its description can be efficient used, i.e., all its attributes that specify if the resource or service can be used by certain service or software. For overtaking it we must define a function that allows to the user to receive the desired and detailed hardware resource attributes.The resources are basically hardware resources and software resources. The hardware resource is characterized by:•the resource type;•the resource name, in some cases can be used an ID(entifier);•the resource location;• a set of its attributes;• a set of its components; we can define in turn a structured resource.The software resource is characterized by:•the resource type;•the resource name, in some cases can be used an ID(entifier);•the needed support that is composed by a set of hardware resources every being quoted with appropriate attributes.The information concerning the authorization, access and security is not detailed here in order to simplify the presentation.The information that describes the hardware resource, software resource and the services, given as XML files, furnished by the grid will be processed in an appropriate way by the specific tools in order to fulfill the system requirements. In order to find the node where a task can be executed, a matching between the resource node in formation and the resource needed for the software resource (of the task) will be done.In [7] is given a detailed resource Schema as a XML file where the authors describe a resource that can contain a structured resource one, its components, and every component having its own attributes and being also a structured one. The resource Schema will be used for describing the resource on the Grid or on the Web and also the needed resource for a software resource or for a service offered by the Web or by the Grid. The main feature of the proposed schema is that it can describe a complex resource. Concerning its usage depending on the level of detail that is given the user that will be some specific agent must be able to parse it and match with the given information offered by the requester.3 The Concepts and Tools used in ModelingA complex application is composed from a set of tasks that generally must interact and that must be processed (executed) in a specified sequencing order. For its execution every task needs a set of specified resources. The resources are specific and every resource has particular properties. In order to define a complete specification for a resource we will use some conventions from [12] that will be extended.In many other grid projects are used various means for describing the dynamic behavior of complex grid applications. These means consist from coupled software components and appropriate data. The data is used for:•mapping the grid application onto the underlying grid middleware;•controlling the workflow and data flow of the grid application.Based on the previous, we need tools that allow describing: •resources of the grid;•basic resources that are required to define the grid job;•the model of the grid job workflow using various concepts like Directed Acyclic Graphs (DAG) [18] or Petri nets derivatives [1], [17].Directed Acyclic Graphs (Figure 1) are widely spread due their structure but they have some disadvantages like: being directed it is impossible to define bidirectional coupling schemes, it is also impossible to define loops. The DAGs describe only the behavior but not the state of the system. The Petri nets can be used to control the workflow of complex applications [1]. Details concerning Petri nets and their properties can be found in [17]. The models for workflow that use Petri nets can be found in papers of van der Aalst [1]. In Figure 2 is given an example of Petri net that is equivalent to the DAG from Figure 1.Figure 1Example of a Directed Acyclic Graph (DAG)Figure 2Example of a Petri Net equivalent to the DAG in Figure 1The Petri nets can be used for modeling the workflow and also to control the workflow of complex applications. In many cases the workflow within grid applications can be equivalent to the data flow. That means that the decision when a software component can be launched in execution depends upon the availability of the input data. As a consequence the tokens in the Petri net represent real data that is exchanged between the software components in the grid. So, the Petri net can be used to model the interaction between software components in the grid represented by software transitions and data resources represented by data places. In order to control the workflow due to the fact that in some cases the workflow is independent from the data flow is necessary to introduce control transitions and control places. In this case the tokens (that represent the process state) need some additional information that is the color of the token so the colored Petri nets [13]. The Petri nets used for modeling the workflow must have some particular properties that can be seen in [1]. These properties are:•the net has one input location and one output location;•the initial marking is that contains only one token in the input location;•the final marking contains only one token in the output location;•from any marking (state) between the initial marking and final marking there is a path to the final marking;•by placing one transition that has an input arc form the output location and an output arc to the input location the Petri net is safe.A formal verification of the modeled system can be used and it is based of the Petri net properties. This verification can be easy done and expressed in a mathematical form. Basic features that can be expressed like: conflict confusion, contact, trap, deadlock are well-defined properties of Petri nets that can be very useful during of the process of optimization of the workflow of a complex gridapplication. We do not enter into the details concerning the features that can be given for express in Petri nets terms of the execution in parallel, sequential execution, definitions of the conditions or loops. There exist many approaches to describe Petri nets with XML-based language, e.g., the Petri Net Markup Language (PNML) [14].Recently, UML activity diagrams [21] have been used for workflow modeling. There exist some approaches [9] that use the UML’s activity diagrams those was added some especially semantic in order to improve a better utility in workflow modeling. The ebXML [8] is used to model e-business services. In the ebXML the event features of activity diagrams are used quite extensively: events being the standard means of communication between different business partners.Business Process Modeling [23] offers also a set of standards and languages that allow expressing the workflow. Based on WfMC [23] documents was developed Business Process Modeling Notation (BPMN) [6] as a language that allows to describe a process that in our case can be a workflow.4 The Service Oriented ArchitectureThe Service Oriented Architecture (SOA) can be understood as the necessary structure that supports communications between services. The service can be defined as a unit of work to be performed on behalf on an entity that can be human user or another program. Service interaction is loosely coupled and self-contained, every interaction being independent one another. The implementation of SOA can use the Simple Object Access Protocol (SOA). The protocol independence of SOA allow to the different consumers to communicate with the service in different ways. A management layer between the providers and consumers ensures a real flexibility regarding implementation protocols.For an efficient usage of SOA, the Service Oriented Integration (SOI) and Service Oriented Management (SOM) were developed. SOI is used instead of the traditional Enterprise Application Integration (EAI). SOI has as significant characteristics:●well defined standardized interfaces-consumers are provided with wellunderstood and consistent access to the underlying service;●opaqueness- the technology and location of application providing thefunctionality is hidden behind the service interface;●flexibility- the service is constant both the provider of the service and theconsumer of the service can change.SOM constitutes the operational management of service delivery within a SOA. One of the major features of the SOM is to provide a differentiated service delivery capability during operation using specific objectives for driving the system behavior. A SOM solution supervises and controls the delivery of a service from a service provider to a service requester. A SOM solution can also be viewed as supervising and controlling the consumptions of services by a requester from a number of providers. A SOM solution should by able to manage any service from any technology without requiring code changes, special deployment, or special development environments.Using a SOA solution we obtain a set of advantages: lower costs, flexibility, the web services that are point to point and it can not solve all the problems, a higher security.5 The Multi-Agent SystemsDue of the complexity of problems around the development of grid applications an adequate and efficient solution can be developed using the agents that act in a multi-agent system. The agents must be designed in order to fulfill their own goals and also the system goals. The agents must cooperate and concur in order to obtain the needed resources. In many approaches is used the negotiation. Negotiation between intelligent agents is one of the basic issues in Distributed Artificial Intelligence and Multi-Agent Systems [3]. A negotiation process tends to modify the own plan of each agent in order to achieve agreement among a subset of agents in the system. One of the main works in this area Contract Net Protocol (CNP) [19] serves as a basis for a lot of variants that are already frequently used. The CNP was initially developed for decentralized task allocation and is a distributed negotiation model based on the notion of call for bids on markets. The relation between clients (managers, customers, buyers) and suppliers (bidders, contractors, sellers) is created in a call for bids and evaluation of the proposals submitted by the bidders to the managers. This CNP has several limits: As a multi-agent system is distributed, several managers can concurrently call for bids, so an agent may have to manage several negotiation processes in parallel in order to reduce the length of its negotiation processes. Some of the applications of the CNP force the contractors to sequence their negotiation processes, i.e., to answer with a single bid at a time. Sequencing the processing of contractor answers to the calls emitted by the various managers may make the contractors miss some contracts. When the multi-agent system is equipped with delay failure detectors, it may also force the managers to consider these contractor agents as failures.CNP-based applications enable the agent to break its commitments when the agent receives an offer for a better task in comparison with those for which the agent is committed. However breaking the commitments is not always a good solution because it makes managers call again for bids to find anew contractors for their tasks.6 The Proposed Framework Based on Multi-Agentand SOASOA is an architectural manner that has as objective to achieve loose coupling among interacting software agents. A service being a unit of work done by a service provider done by achieves desired results for a given consumer, both provider and consumer are roles played by software agents on behalf of their owners. The results of a service are usually the change of state for the consumer, or for the provider or for both. SOA achieve loose coupling among interacting software agents using as architectural constraints:● a small set of interface to all participant software agents. Only genericsemantics are encoded at the interfaces. The interfaces should be universal available for providers and consumers;●descriptive messages constrained by an extensive schema deliveredthrough the interfaces. An extensible schema allows new versions of services to be introduced without breaking existing services.Interfacing in SOA and in distributed applications is important and also expensive and error-prone. The interface prescribes the system behavior and this is very difficult to implement correctly across different platforms and languages. In some cases is recommended to reuse generic interfaces, but this implies that the designer expresses application-specific semantics in messages. Due to the fact that the architecture is service oriented the messages sent must comply with some specific rules:•the messages must be descriptive, rather that instructive, due to the fact that the service provider is responsible for solving the problem;•the vocabulary used must be clear for all (provider and consumer) and the structure of the messages must be also well defined for an efficient communication;•the extensibility allows to evolve the system and it is very important;•the SOA must give to the consumer a mechanism that enables the consumer to discover a service provider under the context of a service sought by the consumer. This mechanism can be flexible and it (if this ispossible) does not have to be a centralized registry (in the Grid the registry is frequently used especially for nodes).In order to improve its scalability, performance and reliability of the SOA the following constraints are needed:•stateless service - the message that a consumer sends to a provider must contain all necessary information for the provider to process it. This makesa service more scalable because the provider does not have to store stateinformation between requests. Each request can be treated as generic. In a way is improved visibility because the monitoring software can inspect one single request and figure out its intention. Due to the fact that there are no intermediate states to worry about the recovery from partial failure is relatively easy and the service becomes more reliable.•stateful service – between the particular situations that must be carefully designed are: the existence of a session between a consumer and a provider due to the reasons of efficiency; providing of a customized service. This kind of services requires both the consumer and the provider to share the same consumer-specific context that is either included in or referenced by messages exchanged between the provider and the consumer. The drawback of this constraint is that it may reduce overall scalability of the service provider because it may need to remember the shared context for each consumer. It also increases the coupling between a service provider and a consumer.•idempotent request – (it can be treated carefully due to the fact that means) duplicate requests received by a software agent have the same effect as a unique request. This allows providers and consumers to improve the overall service reliability by simply repeating the request if faults are encountered.Concerning the service it can be considered in SOA as a piece of functionality whose properties are:•the interface contract to the service is platform independent; the service can be consumed by a client from anywhere, on any OS and in any language;•the service can be dynamically located and invoked; it hints that a discovery service is available. The directory service enable a look-up mechanism where consumers can go to find a service based on some criteria;•the service is self contained, that is the service maintains its own state.In Figure 3 is illustrated the usage of a directory service.Figure 3The usage of a directory serviceIn [12] is proposed a very complex model that uses a Grid Application Definition Language (GADL). It contains a set of XML-based description languages in order to define and assemble complex grid applications for mapping these applications onto the available hardware and software resources and to control the workflow during the execution. The GADL is composed from description languages for resources, interfaces data and jobs. Based on these the user interfaces with by Task mapping, grid job builder and Grid job handler.The complex application executed on the grid (and not only) imposes a strong analysis concerning:•its decomposition in tasks with the specification of the resources that are needed during the task execution;•the tasks sequencing and where the case is the tasks correlation. It is a major challenge the tasks parallelization during their execution;•the failures and erroneous task execution that imposes: the rescheduling or reminded tasks for execution in the new contest; the temporary data storage imposed by the failure and the supplementary services that are required for replying the rest of the tasks execution.Concerning the execution, a task in characterized by:•its identifier;•the preconditioning of the task execution;•the post conditioning (that is unleashed by its execution);•the needed resources and their amount.All these are given in some forms, usually as XML files.The sequencing can be done in some ways, one of these being based on Colored Petri Nets. In this paper it is done in a simplified way using Place/Transition Petri Nets. Using such a representation we are able expressing the: concurrency (the parallelism) and synchronization between tasks (and tasks sequences).In the following figures, we present some of the possibilities that illustrate the modeling of the application execution. In the first one is represented the data flow. Tokens in the places are the data and the transitions are the tasks. The application execution in time is given by tokens flow in the net. Also a tool that manages the Petri net that manages the application execution is needed. The Petri nets used are timed Petri nets. In Figure 4, the data flow and the tokens in the places represent data and the transitions are the tasks execution. Here the sequence of tasks 42,t t and the sequence 53,t t can be executed concurrent (in parallel). The task 6t is synchronization (instant transition). The initial marking of Petri net is )0,0,0,0,0,0,0,0,0,1(i.e., the start of the application. This marking enables [17] the transition (the task 1t ) that fires and based on the Petri net rules the transitions 2t and 3tare enabled and also these transitions can fire.Figure 4 The Petri Net for an applicationA major lack of workflow models is that the case instantiation is treated in isolation. In real life that is not true. The major problem concerns to the resources their contention and sharing (these are not treated by workflow models). Based on an analysis done we propose that the following features to be used:。