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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Distributed knowledge sharing and production through collaborative e-Science platforms

Gaignard, Alban 15 March 2013 (has links) (PDF)
This thesis addresses the issues of coherent distributed knowledge production and sharing in the Life-science area. In spite of the continuously increasing computing and storage capabilities of computing infrastructures, the management of massive scientific data through centralized approaches became inappropriate, for several reasons: (i) they do not guarantee the autonomy property of data providers, constrained, for either ethical or legal concerns, to keep the control over the data they host, (ii) they do not scale and adapt to the massive scientific data produced through e-Science platforms. In the context of the NeuroLOG and VIP Life-science collaborative platforms, we address on one hand, distribution and heterogeneity issues underlying, possibly sensitive, resource sharing ; and on the other hand, automated knowledge production through the usage of these e-Science platforms, to ease the exploitation of the massively produced scientific data. We rely on an ontological approach for knowledge modeling and propose, based on Semantic Web technologies, to (i) extend these platforms with efficient, static and dynamic, transparent federated semantic querying strategies, and (ii) to extend their data processing environment, from both provenance information captured at run-time and domain-specific inference rules, to automate the semantic annotation of ''in silico'' experiment results. The results of this thesis have been evaluated on the Grid'5000 distributed and controlled infrastructure. They contribute to addressing three of the main challenging issues faced in the area of computational science platforms through (i) a model for secured collaborations and a distributed access control strategy allowing for the setup of multi-centric studies while still considering competitive activities, (ii) semantic experiment summaries, meaningful from the end-user perspective, aimed at easing the navigation into massive scientific data resulting from large-scale experimental campaigns, and (iii) efficient distributed querying and reasoning strategies, relying on Semantic Web standards, aimed at sharing capitalized knowledge and providing connectivity towards the Web of Linked Data.
12

Web Service Composition Under Resource Allocation Constraints

Karakoc, Erman 01 April 2007 (has links) (PDF)
Web service composition is an inevitable aspect of web services technology, which solves complex problems by combining available basic services and ordering them to best suit the problem requirements. Automatic composition gives us flexibility of selecting best candidate services at composition time, this would require the user to define the resource allocation constraints for selecting and composing candidate web services. Resource allocation constraints define restrictions on how to allocate resources, and scheduling under resource allocation constraints to provide proper resource allocation to tasks. In this work, web service composition system named as CWSF (Composite Web Service Framework) constructed for users to define a workflow system in which a rich set of constraints can be defined on web services. On the contrary many technologies and studies, CWSF provides a user-friendly environment for modeling web service composition system. The output of the framework is the scheduling of web service composition in which how and when web services are executed are defined. With this work, a language, CWSL is defined to describe workflow, resource allocation constraints, selection and discovery rules of web services and associated semantic information. An important property of CWSF system is converting web service composition problem into a constraint satisfaction problem to find the best solution that meet the all criteria defined by user. Furthermore, CWSF has ability to display other possible solutions to provides users flexibility. This study also includes semantic matching and mapping facilities for service discovery.
13

Semantic Processes For Constructing Composite Web Services

Kardas, Karani 01 September 2007 (has links) (PDF)
In Web service composition, service discovery and combining suitable services through determination of interoperability among different services are important operations. Utilizing semantics improves the quality and facilitates automation of these operations. There are several previous approaches for semantic service discovery and service matching. In this work, we exploit and extend these semantic approaches in order to make Web service composition process more facilitated, less error prone and more automated. This work includes a service discovery and service interoperability checking technique which extends the previous semantic matching approaches. In addition to this, as a guidance system for the user, a new semantic domain model is proposed that captures semantic relations between concepts in various ontologies.
14

Automatic Composition Of Semantic Web Services With The Abductive Event Calculus

Kirci, Esra 01 September 2008 (has links) (PDF)
In today&#039 / s world, composite web services are widely used in service oriented computing, web mashups and B2B Applications etc. Most of these services are composed manually. However, the complexity of manually composing web services increase exponentially with the increase in the number of available web services, the need for dynamically created/updated/discovered services and the necessity for higher amount of data bindings and type mappings in longer compositions. Therefore, current highly manual web service composition techniques are far from being the answer to web service composition problem. Automatic web service composition methods are recent research efforts to tackle the issues with manual techniques. Broadly, these methods fall into two groups: (i) workflow based methods and (ii) methods using AI planning. This thesis investigates the application of AI planning techniques to the web service composition problem and in particular, it proposes the use of the abductive event calculus in this domain. Web service compositions are defined as templates using OWL-S (&quot / OWL for Services&quot / ). These generic composition definitions are converted to Prolog language as axioms for the abductive event calculus planner and solutions found by the planner constitute the specific result plans for the generic composition plan. In this thesis it is shown that abductive planning capabilities of the event calculus can be used to generate the web service composition plans that realize the generic procedure.
15

Abductive Planning Approach For Automated Web Service Composition Using Only User Specified Inputs And Outputs

Kuban, Esat Kaan 01 February 2009 (has links) (PDF)
In recent years, web services have become an emerging technology for communication and integration between applications in many areas such as business to business (B2B) or business to commerce (B2C). In this growing technology, it is hard to compose web services manually because of the increasing number and compexity of web services. Therefore, automation of this composition process has gained a considerable amount of popularity. Automated web service composition can be achieved either by generating the composition plan dynamically using given inputs and outputs, or by locating the correct services if an abstract process model is given. This thesis investigates the former method which is dynamicly generating the composition by using the abductive lanning capabilities of the Event Calculus. Event calculus axioms in Prolog language, are generated using the available OWL-S web service descriptions in the service repository, values given to selected inputs from ontologies used by those semantic web services and desired output types selected again from the ontologies. Abductive Theorem Prover which is the AI planner used in this thesis, generates composition plans and execution results according to the generated event calculus axioms. In this thesis, it is shown that abductive event calculus can be used for generating web services composition plans automatically, and returning the results of the generated plans by executing the necessary web services.
16

Automatic Web Service Composition With Ai Planning

Kuzu, Mehmet 01 July 2009 (has links) (PDF)
In this thesis, some novel ideas are presented for solving automated web service composition problem. Some possible real world problems such as partial observability of environment, nondeterministic effects of web services, service execution failures are solved through some mechanisms. In addition to automated web service composition, automated web service invocation task is handled in this thesis by using reflection mechanism. The proposed approach is based on AI planning. Web service composition problem is translated to AI planning problem and a novel AI planner namely &ldquo / Simplanner&rdquo / that is designed for working in highly dynamic environments under time constraints is adapted to the proposed system. World altering service calls are done by conforming to the WS-Coordination and WS-Business Activity web service transaction specifications in order to physically repair failure situations and prevent undesired side effects of aborted web service composition efforts.
17

A Monolithic Approach To Automated Composition Of Semantic Web Services With The Event Calculus

Okutan, Cagla 01 September 2009 (has links) (PDF)
In this thesis, a web service composition and execution framework is presented for semantically annotated web services. A monolithic approach to automated web service composition and execution problem is chosen, which provides some benefits by separating the composition and execution phases. An AI planning method using a logical formalism called Event Calculus is chosen for the composition phase. This formalism allows one to generate a narrative of actions and temporal orderings using abductive planning techniques given a goal. Functional properties of services, namely input/output/precondition/effects(IOPE) are taken into consideration in the composition phase and non-functional properties, namely quality of service (QoS) parameters are used in selecting the most appropriate solution to be executed. The repository of OWL-S semanticWeb services are translated to Event Calculus axioms and the resulting plans found by the Abductive Event Calculus Planner are converted to graphs. These graphs can be sorted according to a score calculated using the defined quality of service parameters of the atomic services in the composition to determine the optimal solution. The selected graph is converted to an OWL-S file which is executed consequently.
18

Providing Scalability For An Automated Web Service Composition Framework

Kaya, Ertay 01 June 2010 (has links) (PDF)
In this thesis, some enhancements to an existing automatic web service composition and execution system are described which provide a practical significance to the existing framework with scalability, i.e. the ability to operate on large service sets in reasonable time. In addition, the service storage mechanism utilized in the enhanced system presents an effective method to maintain large service sets. The described enhanced system provides scalability by implementing a pre-processing phase that extracts service chains and problem initial and goal state dependencies from service descriptions. The service storage mechanism is used to store this extracted information and descriptions of available services. The extracted information is used in a forward chaining algorithm which selects the potentially useful services for a given composition problem and eliminates the irrelevant ones according to the given problem initial and goal states. Only the selected services are used during the AI planning and execution phases which generate the composition and execute the services respectively.
19

Vers une plateforme dédiée à la composition automatique et l'exécution de services : Applications E-Tourisme / Toward a framework for automated service composition and execution : E-tourism Applications

Na lumpoon, Pathathai 12 May 2015 (has links)
Les systèmes de services contextualisés ont connu un grand essor ces dernières années dans des domaines variés tels que la santé, la logistique ou bien le tourisme. Cette thèse s'intègre dans un projet plus global, nommé E-Tourism, qui vise à réaliser une plateforme de fourniture de services sensibles au contexte à des utilisateurs en situation de mobilité. Le travail de cette thèse se focalise sur la problématique de composition de services web et de leur exécution. La composition de services web permet la réutilisation de services existants afin d'en faire une synthèse répondant au besoin de l'utilisateur. Cette composition se fait en général au niveau de la phase conceptuelle ce qui limite le choix de services potentiels. Cette thèse présente une nouvelle approche de la composition de services Web automatisé et une plateforme d'exécution. Notre approche vise à composer les opérations de services qui répondent aux besoins des utilisateurs mobiles exprimées dans une logique propositionnelle et exécuter le service composé en agrégeant plusieurs services composants. Nous avons proposé une plateforme d'exécution de services et nous avons introduit un nouvel algorithme de planification intégré à cette plateforme. Nous avons défini un contexte basé sur le modèle BPMN. Afin de valider notre modèle sémantique nous avons utilisé une approche de type « model-checking » . Enfin, nous avons réalisé un prototype sous forme d'une plateforme de composition de services et d'exécution automatique en Java. Nous avons implémenté les règles d'inférence et les modèles BPMN en prolog. Enfin, nous avons intégré ces algorithmes dans l'ensemble du système. En perspectives, nous prévoyons d'étendre notre travail actuel et prendre en compte des scénarios plus complexes nécessitant des services web dynamiques. / Recently, distributed computing systems based on context awareness have been proposing in several domains such as healthcare, logistics and tourism. The study described in this thesis is a part of a broader project of E-Tourism system that provides nomad user, context-aware personalized services. The work of this thesis focuses on the issues raised by web service composition and execution. Web service composition brings benefits of reusing existing services to synthesize the new resulting service that meets users needs. The way to create web service composition normally happens at design time, but this limits choices of services. This thesis presents a novel approach of automated web service composition and execution framework. Our approach aims to compose service operations that fulfill mobile users' requirements expressed in propositional logic and execute the resulting service based on aggregating multi service components. In the proposed framework, we have introduced our planning algorithm based on abstract goal states to search and connect to service operations, by mean of service operation annotations, for an abstract plan. The abstract plan is expected for workflow model of sequencing, paralleling and conditioning among service operations. However, the generated workflow is not in an executable form, this is why we perform the transformation of the workflow into an executable business process. To achieve the business process execution, we defined context based BPMN model for mapping the abstract plan to BPMN semantics. We also propose a new validation algorithm and exploited planning-as-model-checking approach to validate the semantic BPMN model whether it is Well-formed and Well-defined BPMN process. Finally, we implemented the automated service composition and execution framework system in Java platform as a proof of concept. We developed the logical composition and, transformation and validation BPMN algorithms written in Prolog. We have integrated these algorithms into the whole system. From the perspective, we plan to extend our current work and take into account more complex user's scenarios that explicitly and implicitly express other pattern controls and we will also consider the scenarios required for stateful web services
20

Vers une plateforme dédiée à la composition automatique et l'exécution de services : Applications E-Tourisme / Toward a framework for automated service composition and execution : E-tourism Applications

Na lumpoon, Pathathai 12 May 2015 (has links)
Les systèmes de services contextualisés ont connu un grand essor ces dernières années dans des domaines variés tels que la santé, la logistique ou bien le tourisme. Cette thèse s'intègre dans un projet plus global, nommé E-Tourism, qui vise à réaliser une plateforme de fourniture de services sensibles au contexte à des utilisateurs en situation de mobilité. Le travail de cette thèse se focalise sur la problématique de composition de services web et de leur exécution. La composition de services web permet la réutilisation de services existants afin d'en faire une synthèse répondant au besoin de l'utilisateur. Cette composition se fait en général au niveau de la phase conceptuelle ce qui limite le choix de services potentiels. Cette thèse présente une nouvelle approche de la composition de services Web automatisé et une plateforme d'exécution. Notre approche vise à composer les opérations de services qui répondent aux besoins des utilisateurs mobiles exprimées dans une logique propositionnelle et exécuter le service composé en agrégeant plusieurs services composants. Nous avons proposé une plateforme d'exécution de services et nous avons introduit un nouvel algorithme de planification intégré à cette plateforme. Nous avons défini un contexte basé sur le modèle BPMN. Afin de valider notre modèle sémantique nous avons utilisé une approche de type « model-checking » . Enfin, nous avons réalisé un prototype sous forme d'une plateforme de composition de services et d'exécution automatique en Java. Nous avons implémenté les règles d'inférence et les modèles BPMN en prolog. Enfin, nous avons intégré ces algorithmes dans l'ensemble du système. En perspectives, nous prévoyons d'étendre notre travail actuel et prendre en compte des scénarios plus complexes nécessitant des services web dynamiques. / Recently, distributed computing systems based on context awareness have been proposing in several domains such as healthcare, logistics and tourism. The study described in this thesis is a part of a broader project of E-Tourism system that provides nomad user, context-aware personalized services. The work of this thesis focuses on the issues raised by web service composition and execution. Web service composition brings benefits of reusing existing services to synthesize the new resulting service that meets users needs. The way to create web service composition normally happens at design time, but this limits choices of services. This thesis presents a novel approach of automated web service composition and execution framework. Our approach aims to compose service operations that fulfill mobile users' requirements expressed in propositional logic and execute the resulting service based on aggregating multi service components. In the proposed framework, we have introduced our planning algorithm based on abstract goal states to search and connect to service operations, by mean of service operation annotations, for an abstract plan. The abstract plan is expected for workflow model of sequencing, paralleling and conditioning among service operations. However, the generated workflow is not in an executable form, this is why we perform the transformation of the workflow into an executable business process. To achieve the business process execution, we defined context based BPMN model for mapping the abstract plan to BPMN semantics. We also propose a new validation algorithm and exploited planning-as-model-checking approach to validate the semantic BPMN model whether it is Well-formed and Well-defined BPMN process. Finally, we implemented the automated service composition and execution framework system in Java platform as a proof of concept. We developed the logical composition and, transformation and validation BPMN algorithms written in Prolog. We have integrated these algorithms into the whole system. From the perspective, we plan to extend our current work and take into account more complex user's scenarios that explicitly and implicitly express other pattern controls and we will also consider the scenarios required for stateful web services

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