908 resultados para Semantic Web Services


Relevância:

80.00% 80.00%

Publicador:

Resumo:

It is problematic to use standard ontology tools when describing vague domains. Standard ontologies are designed to formally define one view of a domain, and although it is possible to define disagreeing statements, it is not advisable, as the resulting inferences could be incorrect. Two different solutions to the above problem in two different vague domains have been developed and are presented. The first domain is the knowledge base of conversational agents (chatbots). An ontological scripting language has been designed to access ontology data from within chatbot code. The solution developed is based on reifications of user statements. It enables a new layer of logics based on the different views of the users, enabling the body of knowledge to grow automatically. The second domain is competencies and competency frameworks. An ontological framework has been developed to model different competencies using the emergent standards. It enables comparison of competencies using a mix of linguistic logics and descriptive logics. The comparison results are non-binary, therefore not simple yes and no answers, highlighting the vague nature of the comparisons. The solution has been developed with small ontologies which can be added to and modified in order for the competency user to build a total picture that fits the user’s purpose. Finally these two approaches are viewed in the light of how they could aid future work in vague domains, further work in both domains is described and also in other domains such as the semantic web. This demonstrates two different approaches to achieve inferences using standard ontology tools in vague domains.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

In recent years, life event approach has been widely used by governments all over the world for designing and providing web services to citizens through their e-government portals. Despite the wide usage of this approach, there is still a challenge of how to use this approach to design e-government portals in order to automatically provide personalised services to citizens. We propose a conceptual framework for e-government service provision based on life event approach and the use of citizen profile to capture the citizen needs, since the process of finding Web services from a government-to-citizen (G2C) system involves understanding the citizens’ needs and demands, selecting the relevant services, and delivering services that matches the requirements. The proposed framework that incorporates the citizen profile is based on three components that complement each other, namely, anticipatory life events, non-anticipatory life events and recurring services.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

SOA (Service Oriented Architecture), workflow, the Semantic Web, and Grid computing are key enabling information technologies in the development of increasingly sophisticated e-Science infrastructures and application platforms. While the emergence of Cloud computing as a new computing paradigm has provided new directions and opportunities for e-Science infrastructure development, it also presents some challenges. Scientific research is increasingly finding that it is difficult to handle “big data” using traditional data processing techniques. Such challenges demonstrate the need for a comprehensive analysis on using the above mentioned informatics techniques to develop appropriate e-Science infrastructure and platforms in the context of Cloud computing. This survey paper describes recent research advances in applying informatics techniques to facilitate scientific research particularly from the Cloud computing perspective. Our particular contributions include identifying associated research challenges and opportunities, presenting lessons learned, and describing our future vision for applying Cloud computing to e-Science. We believe our research findings can help indicate the future trend of e-Science, and can inform funding and research directions in how to more appropriately employ computing technologies in scientific research. We point out the open research issues hoping to spark new development and innovation in the e-Science field.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

The move towards web services in Grid computing requires mechanisms for services to maintain state. This is introduced by the Web Services Resource Framework which provides a basis for web services to access stateful resources. While this allows access to stateful resources, the web services themselves are not stateful. Currently, Grids require a lot of direct involvement of application developers, who are, in general, not computing specialists. The principles of autonomic computing introduce characteristics which are aimed at automatic improvement of computing systems and can be applied to the Grid. This paper addresses the principles of self healing and self configuration in a Grid environment and implements a service using the WSRF.NET framework to investigate the affect and applicability of the Web Services Resource Framework on these principles and improve the WSRF specification.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Service discovery is a critical task in service-oriented architectures such as the Grid and Web Services. In this paper, we study a semantics enabled service registry, GRIMOIRES, from a performance perspective. GRIMOIRES is designed to be the registry for myGrid and the OMII software distribution. We study the scalability of GRIMOIRES against the amount of information that has been published into it. The methodology we use and the data we present are helpful for researchers to understand the performance characteristics of the registry and, more generally, of semantics enabled service discovery. Based on this experimentation, we claim that GRIMOIRES is an efficient semantics-aware service discovery engine.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Service discovery is a critical task in service-oriented architectures such as the Grid and Web Services. In this paper, we study a semantics enabled service registry, GRIMOIRES, from a performance perspective. GRIMOIRES is designed to be the registry for myGrid and the OMII software distribution. We study the scalability of GRIMOIRES against the amount of information that has been published into it. The methodology we use and the data we present are helpful for researchers to understand the performance characteristics of the registry and, more generally, of semantics enabled service discovery. Based on this experimentation, we claim that GRIMOIRES is an efficient semantics-aware service discovery engine.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Recent work has begun exploring the characterization and utilization of provenance in systems based on the Service Oriented Architecture (such as Web Services and Grid based environments). One of the salient issues related to provenance use within any given system is its security. In a broad sense, security requirements arise within any data archival and retrieval system, however provenance presents unique requirements of its own. These requirements are additionally dependent on the architectural and environmental context that a provenance system operates in. We seek to analyze the security considerations pertaining to a Service Oriented Architecture based provenance system. Towards this end, we describe the components of such a system and illustrate the security considerations that arise within it. Concurrently, we outline possible approaches to address them.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Determining the provenance of data, i.e. the process that led to that data, is vital in many disciplines. For example, in science, the process that produced a given result must be demonstrably rigorous for the result to be deemed reliable. A provenance system supports applications in recording adequate documentation about process executions to answer queries regarding provenance, and provides functionality to perform those queries. Several provenance systems are being developed, but all focus on systems in which the components are textitreactive, for example Web Services that act on the basis of a request, job submission system, etc. This limitation means that questions regarding the motives of autonomous actors, or textitagents, in such systems remain unanswerable in the general case. Such questions include: who was ultimately responsible for a given effect, what was their reason for initiating the process and does the effect of a process match what was intended to occur by those initiating the process? In this paper, we address this limitation by integrating two solutions: a generic, re-usable framework for representing the provenance of data in service-oriented architectures and a model for describing the goal-oriented delegation and engagement of agents in multi-agent systems. Using these solutions, we present algorithms to answer common questions regarding responsibility and success of a process and evaluate the approach with a simulated healthcare example.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Dynamic composition of services provides the ability to build complex distributed applications at run time by combining existing services, thus coping with a large variety of complex requirements that cannot be met by individual services alone. However, with the increasing amount of available services that differ in granularity (amount of functionality provided) and qualities, selecting the best combination of services becomes very complex. In response, this paper addresses the challenges of service selection, and makes a twofold contribution. First, a rich representation of compositional planning knowledge is provided, allowing the expression of multiple decompositions of tasks at arbitrary levels of granularity. Second, two distinct search space reduction techniques are introduced, the application of which, prior to performing service selection, results in significant improvement in selection performance in terms of execution time, which is demonstrated via experimental results.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Corporate information technology (IT) management is increasingly service-oriented, offering continuous evaluation and improvement of application, communication, delivery and support services to internal and external customers. Service-oriented requirements engineering (SoRE) plays a significant role in identifying and specifying service requirements, formally defined through service-level agreements (SLAs). However, the new frameworks and approaches emerging to guide these developments have not yet addressed how requirements for such services can be effectively developed, nor identified the diverse issues involved. We report a case study of a web services team development of requirements for an internal Service Desk service. The study revealed five main issues of concern when developing service provider requirements: service roles, responsibilities and accountability; service performance metrics; resolution of conflicting stakeholder service requirements; customer acceptance of service change; and service provider team structure. This study suggests that in the new IT services era, new techniques and approaches are needed for eliciting and determining provider and customer requirements that involve key stakeholder groups equitably and more closely negotiate the sometimes-conflicting provider and customer needs.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Text-based information accounts for more than 80% of today’s Web content. They consist of Web pages written in different natural languages. As the semantic Web aims at turning the current Web into a machine-understandable knowledge repository, availability of multilingual ontology thus becomes an issue at the core of a multilingual semantic Web. However, multilingual ontology is too complex and resource intensive to be constructed manually. In this paper, we propose a three-layer model built on top of a soft computing framework to automatically acquire a multilingual ontology from domain specific parallel texts. The objective is to enable semantic smart information access regardless of language over the Semantic Web.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

With the recent innovations in stateful web services, they are now being used to support the construction of distributed systems using software as a service. While the state of web services is preserved, the state is still hidden from clients thus searches for both functionality and state remains a two step process. Proposed in this report is the Resources Via Web Instances (RVWI) framework. RVWI grants to web services the ability to include their state and characteristics in their WSDL. This was done by allowing snapshots (instances) of a web service to be listed in the WSDL of the web service. Instances were utilised as they contain state and characteristic information directly from the web service. Thanks to the inclusion of state and characteristics, queries for web services can now be carried out on the availability of a web service and the 'dimensions' of resources..