12 research outputs found
Designing and trusting multi-agent systems for B2B applications
This thesis includes two main contributions. The first one is designing and implementing B usiness-to-B usiness (B2B ) applications using multi-agent systems and computational argumentation theory. The second one is trust management in such multi-agent systems using agents' credibility. Our first contribution presents a framework for modeling and deploying B2B applications, with autonomous agents exposing the individual components that implement these applications. This framework consists of three levels identified by strategic, application, and resource, with focus here on the first two levels. The strategic level is about the common vision that independent businesses define as part of their decision of partnership. The application level is about the business processes, which are virtually integrated as result of this common vision. Since conflicts are bound to arise among the independent applications/agents, the framework uses a formal model based upon computational argumentation theory through a persuasion protocol to detect and resolve these conflicts. Termination, soundness, and completeness properties of this protocol are presented. Distributed and centralized coordination strategies are also supported in this framework, which is illustrated with an online purchasing case study followed by its implementation in Jadex, a java-based platform for multi-agent systems. An important issue in such open multi-agent systems is how much agents trust each other. Considering the size of these systems, agents that are service providers or customers in a B2B setting cannot avoid interacting with others that are unknown or partially known regarding to some past experience. Due to the fact that agents are self-interested, they may jeopardize the mutual trust by not performing the actions as they are supposed to. To this end, our second contribution is proposing a trust model allowing agents to evaluate the credibility of other peers in the environment. Our multi-factor model applies a number of measurements in trust evaluation of other party's likely behavior. After a period of time, the actual performance of the testimony agent is compared against the information provided by interfering agents. This comparison process leads to both adjusting the credibility of the contributing agents in trust evaluation and improving the system trust evaluation by minimizing the estimation error
IngĂ©nierie et Architecture dâEntreprise et des SystĂšmes dâInformation - Concepts, Fondements et MĂ©thodes
L'ingĂ©nierie des systĂšmes d'information s'est longtemps cantonnĂ©e Ă la modĂ©lisation du produit (objet) qu'est le systĂšme dâinformation sans se prĂ©occuper des processus d'usage de ce systĂšme. Dans un environnement de plus en plus Ă©volutif, la modĂ©lisation du fonctionnement du systĂšme dâinformation au sein de l'entreprise me semble primordiale. Pendant les deux derniĂšres dĂ©cennies, les pratiques de management, dâingĂ©nierie et dâopĂ©ration ont subi des mutations profondes et multiformes. Nous devons tenir compte de ces mutations dans les recherches en ingĂ©nierie des systĂšmes dâinformation afin de produire des formalismes et des dĂ©marches mĂ©thodologiques qui sauront anticiper et satisfaire les nouveaux besoins, regroupĂ©s dans ce document sous quatre thĂšmes:1) Le systĂšme dâinformation est le lieu mĂȘme oĂč sâĂ©labore la coordination des actes et des informations sans laquelle une entreprise (et toute organisation), dans la diversitĂ© des mĂ©tiers et des compĂ©tences quâelle met en Ćuvre, ne peut exister que dans la mĂ©diocritĂ©. La comprĂ©hension des exigences de coopĂ©ration dans toutes ses dimensions (communication, coordination, collaboration) et le support que lâinformatique peut et doit y apporter deviennent donc un sujet digne dâintĂ©rĂȘt pour les recherches en systĂšme dâinformation.2) Le paradigme de management des processus dâentreprise (BPM) est en forte opposition avec le dĂ©veloppement traditionnel des systĂšmes dâinformation qui, pendant plusieurs dĂ©cennies, a cristallisĂ© la division verticale des activitĂ©s des organisations et favorisĂ© ainsi la construction dâĂźlots dâinformation et dâapplications. Cependant, les approches traditionnelles de modĂ©lisation de processus ne sont pas Ă la hauteur des besoins dâingĂ©nierie des processus dans ce contexte en constant changement, que ce dernier soit de nature contextuelle ou permanente. Nous avons donc besoin de formalismes (i) qui permettent non seulement de reprĂ©senter les processus dâentreprise et leurs liens avec les composants logiciels du systĂšme existant ou Ă venir mais (ii) qui ont aussi lâaptitude Ă reprĂ©senter la nature variable et/ou Ă©volutive (donc parfois Ă©minemment dĂ©cisionnelle) de ces processus.3) Les systĂšmes dâinformation continuent aujourdâhui de supporter les besoins classiques tels que lâautomatisation et la coordination de la chaĂźne de production, lâamĂ©lioration de la qualitĂ© des produits et/ou services offerts. Cependant un nouveau rĂŽle leur est attribuĂ©. Il sâagit du potentiel offert par les systĂšmes dâinformation pour adopter un rĂŽle de support au service de la stratĂ©gie de lâentreprise. Les technologies de lâinformation, de la communication et de la connaissance se sont ainsi positionnĂ©es comme une ressource stratĂ©gique, support de la transformation organisationnelle voire comme levier du changement. Les modĂšles dâentreprise peuvent reprĂ©senter lâĂ©tat actuel de lâorganisation afin de comprendre, de disposer dâune reprĂ©sentation partagĂ©e, de mesurer les performances, et Ă©ventuellement dâidentifier les dysfonctionnements. Ils permettent aussi de reprĂ©senter un Ă©tat futur souhaitĂ© afin de dĂ©finir une cible vers laquelle avancer par la mise en Ćuvre des projets. Lâentreprise Ă©tant en mouvement perpĂ©tuel, son Ă©volution fait partie de ses multiples dimensions. Nous avons donc besoin de reprĂ©senter, a minima, un Ă©tat futur et le chemin de transformation Ă construire pour avancer vers cette cible. Cependant planifier/imaginer/se projeter vers une cible unique et, en supposant que lâon y arrive, croire quâil puisse exister un seul chemin pour lâatteindre semble irrĂ©aliste. Nous devons donc proposer des formalismes qui permettront de spĂ©cifier des scenarii Ă la fois pour des cibles Ă atteindre et pour des chemins Ă parcourir. Nous devons aussi dĂ©velopper des dĂ©marches mĂ©thodologiques pour guider de maniĂšre systĂ©matique la construction de ces modĂšles dâentreprise et la rationalitĂ© sous-jacente.4) En moins de cinquante ans, le propos du systĂšme dâinformation a Ă©voluĂ© et sâest complexifiĂ©. Aujourdâhui, le systĂšme dâinformation doit supporter non seulement les fonctions de support de maniĂšre isolĂ©e et en silos (1970-1990), et les activitĂ©s appartenant Ă la chaĂźne de valeur [Porter, 1985] de lâentreprise (1980-2000) mais aussi les activitĂ©s de contrĂŽle, de pilotage, de planification stratĂ©gique ainsi que la cohĂ©rence et lâharmonie de lâensemble des processus liĂ©s aux activitĂ©s mĂ©tier (2000-201x), en un mot les activitĂ©s de management stratĂ©gique et de gouvernance dâentreprise. La gouvernance d'entreprise est l'ensemble des processus, rĂ©glementations, lois et institutions influant la maniĂšre dont l'entreprise est dirigĂ©e, administrĂ©e et contrĂŽlĂ©e. Ces processus qui produisent des âdĂ©cisionsâ en guise de âproduitâ ont autant besoin dâĂȘtre instrumentalisĂ©s par les systĂšmes dâinformation que les processus de nature plus opĂ©rationnels de lâentreprise. De mĂȘme, ces processus stratĂ©giques (dits aussi âde dĂ©veloppementâ) nĂ©cessitent dâavoir recours Ă des formalismes de reprĂ©sentation qui sont trĂšs loin, en pouvoir dâexpression, des notations largement adoptĂ©es ces derniĂšres annĂ©es pour la reprĂ©sentation des processus dâentreprise.Ainsi, il semble peu judicieux de vouloir (ou penser pouvoir) isoler, pendant sa construction, lâobjet âsystĂšme dâinformationâ de son environnement dâexĂ©cution. Si le sens donnĂ© Ă lâinformation dĂ©pend de la personne qui la reçoit, ce sens ne peut ĂȘtre entiĂšrement capturĂ© dans le systĂšme technique. Il sera plutĂŽt apprĂ©hendĂ© comme une composante essentielle dâun systĂšme socio-technique incluant les usagers du systĂšme dâinformation technologisĂ©, autrement dit, les acteurs agissant de lâentreprise. De mon point de vue, ce systĂšme socio-technique qui mĂ©rite lâintĂ©rĂȘt scientifique de notre discipline est lâentreprise. Les recherches que jâai rĂ©alisĂ©es, animĂ©es ou supervisĂ©es , et qui sont structurĂ©es en quatre thĂšmes dans ce document, visent Ă rĂ©soudre les problĂšmes liĂ©s aux contextes de l'usage (l'entreprise et son environnement) des systĂšmes dâinformation. Le point discriminant de ma recherche est l'intĂ©rĂȘt que je porte Ă la capacitĂ© de reprĂ©sentation :(i) de l'Ă©volutivitĂ© et de la flexibilitĂ© des processus d'entreprise en particulier de ceux supportĂ©s par un systĂšme logiciel, dâun point de vue microscopique (modĂšle dâun processus) et macroscopique (reprĂ©sentation et configuration dâun rĂ©seau de processus) : thĂšme 2(ii) du systĂšme dâentreprise dans toutes ses dimensions (stratĂ©gie, organisation des processus, systĂšme dâinformation et changement) : thĂšme 3Pour composer avec ces motivations, il fallait :(iii) sâintĂ©resser Ă la nature mĂȘme du travail coopĂ©ratif et Ă lâintentionnalitĂ© des acteurs agissant afin dâidentifier et/ou proposer des formalismes appropriĂ©s pour les dĂ©crire et les comprendre : thĂšme 1(iv) se questionner aussi sur les processus de management dont le rĂŽle est de surveiller, mesurer, piloter lâentreprise afin de leur apporter le soutien quâils mĂ©ritent du systĂšme dâinformation : thĂšme
Requirement validation with enactable descriptions of use cases.
The validation of stakeholder requirements for a software system is a pivotal activity for any nontrivial software development project. Often, differences in knowledge regarding development issues, and knowledge regarding the problem domain, impede the elaboration of requirements amongst developers and stakeholders. A description technique that provides a user perspective of the system
behaviour is likely to enhance shared understanding between the developers and stakeholders. The Unified Modelling Language (UML) use case is such a notation. Use cases describe the behaviour of a system (using natural language) in terms of interactions between the external users and the system. Since the standardisation of the UML by the Object Management Group in 1997, much research has been devoted to use cases. Some researchers have focussed on the provision of writing guidelines for use case specifications whereas others have focussed on the application of formal techniques. This thesis investigates the adequacy of the use case description for the specification and validation of
software behaviour. In particular, the thesis argues that whereas the user-system interaction scheme underpins the essence of the use case notation, the UML specification of the use case does not provide a mechanism by which use cases can describe dependencies amongst constituent interaction steps. Clarifying these issues is crucial for validating the adequacy of the specification against stakeholder expectations. This thesis proposes a state-based approach (the Educator approach) to use case specification where constituent events are augmented with pre and post states to express both intra-use case and
inter-use case dependencies. Use case events are enacted to visualise implied behaviour, thereby enhancing shared understanding among users and developers. Moreover, enaction provides an early "feel" of the behaviour that would result from the implementation of the specification. The Educator approach and the enaction of descriptions are supported by a prototype environment, the EducatorTool,
developed to demonstrate the efficacy and novelty of the approach. To validate the work presented in this thesis an industrial study, involving the specification of realtime
control software, is reported. The study involves the analysis of use case specifications of the subsystems prior to the application of the proposed approach, and the analysis of the specification where the approach and tool support are applied. This way, it is possible to determine the efficacy of the Educator approach within an industrial setting
Factors affecting the development of sophisticated database marketing systems.
In the late 1980s, companies in a wide variety of industries began to implement segmented marketing strategies using database marketing (DBM) systems. Several surveys noted that some organisations were developing sophisticated DBM systems to achieve competitive advantage, while others, in similar marketplaces, seemed unable, or unwilling, to exploit the potential benefits of these powerful systems. Alternatively, evidence from industrial reports suggested that most companies were failing to fully exploit the capabilities oftheir systems. Hence, this research was designed to determine the factors affecting levels of sophistication in database marketing (DBM) systems.
First, theories from marketing and information systems were synthesised to develop a generic model of DBM systems. Next, notions about the sources of competitive advantage were reviewed to identify potential factors promoting the development of sophisticated DBM systems. This review resulted in four such factors being hypothesised: market orientation as a specific organisation culture, database size (i.e. number of customers) as a key resource, locus of control of the senior marketing manager as an important individual characteristic, and the difference between consumer and business markets as a factor in firms' external environment.
Empirical data were collected from two random samples of senior marketing managers in US catalogue companies using postal surveys. Data from the first sample (36 observations) were used to develop a valid and reliable construct to measure the level of sophistication in DBM systems. Further data were collected from a second random sample using two further postal surveys (69 observations), which confirmed and replicated the results obtained from the first sample.
Overall, the research findings show that the development of sophisticated DBM systems is positively associated with two factors: market orientation of organisation culture, and database size. The other two factors - locus of control and type of market - failed to show any association with the level of sophistication in DBM systems. Further data analyses revealed a strong association between the elements of sophisticated OBM systems and marketing notions of sources of competitive advantage
Requirement validation with enactable descriptions of use cases
The validation of stakeholder requirements for a software system is a pivotal activity for any nontrivial software development project. Often, differences in knowledge regarding development issues, and knowledge regarding the problem domain, impede the elaboration of requirements amongst developers and stakeholders. A description technique that provides a user perspective of the system behaviour is likely to enhance shared understanding between the developers and stakeholders. The Unified Modelling Language (UML) use case is such a notation. Use cases describe the behaviour of a system (using natural language) in terms of interactions between the external users and the system. Since the standardisation of the UML by the Object Management Group in 1997, much research has been devoted to use cases. Some researchers have focussed on the provision of writing guidelines for use case specifications whereas others have focussed on the application of formal techniques. This thesis investigates the adequacy of the use case description for the specification and validation of software behaviour. In particular, the thesis argues that whereas the user-system interaction scheme underpins the essence of the use case notation, the UML specification of the use case does not provide a mechanism by which use cases can describe dependencies amongst constituent interaction steps. Clarifying these issues is crucial for validating the adequacy of the specification against stakeholder expectations. This thesis proposes a state-based approach (the Educator approach) to use case specification where constituent events are augmented with pre and post states to express both intra-use case and inter-use case dependencies. Use case events are enacted to visualise implied behaviour, thereby enhancing shared understanding among users and developers. Moreover, enaction provides an early "feel" of the behaviour that would result from the implementation of the specification. The Educator approach and the enaction of descriptions are supported by a prototype environment, the EducatorTool, developed to demonstrate the efficacy and novelty of the approach. To validate the work presented in this thesis an industrial study, involving the specification of realtime control software, is reported. The study involves the analysis of use case specifications of the subsystems prior to the application of the proposed approach, and the analysis of the specification where the approach and tool support are applied. This way, it is possible to determine the efficacy of the Educator approach within an industrial setting.EThOS - Electronic Theses Online ServiceGBUnited Kingdo
Health Sciences handbook
2004 handbook for the faculty of Health Science