803 resultados para composite web services


Relevância:

100.00% 100.00%

Publicador:

Resumo:

This short position paper considers issues in developing Data Architecture for the Internet of Things (IoT) through the medium of an exemplar project, Domain Expertise Capture in Authoring and Development ­Environments (DECADE). A brief discussion sets the background for IoT, and the development of the ­distinction between things and computers. The paper makes a strong argument to avoid reinvention of the wheel, and to reuse approaches to distributed heterogeneous data architectures and the lessons learned from that work, and apply them to this situation. DECADE requires an autonomous recording system, ­local data storage, semi-autonomous verification model, sign-off mechanism, qualitative and ­quantitative ­analysis ­carried out when and where required through web-service architecture, based on ontology and analytic agents, with a self-maintaining ontology model. To develop this, we describe a web-service ­architecture, ­combining a distributed data warehouse, web services for analysis agents, ontology agents and a ­verification engine, with a centrally verified outcome database maintained by certifying body for qualification/­professional status.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

A service is a remote computational facility which is made available for general use by means of a wide-area network. Several types of service arise in practice: stateless services, shared state services and services with states which are customised for individual users. A service-based orchestration is a multi-threaded computation which invokes remote services in order to deliver results back to a user (publication). In this paper a means of specifying services and reasoning about the correctness of orchestrations over stateless services is presented. As web services are potentially unreliable the termination of even finite orchestrations cannot be guaranteed. For this reason a partial-correctness powerdomain approach is proposed to capture the semantics of recursive orchestrations.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

A web-service is a remote computational facility which is made available for general use by means of the internet. An orchestration is a multi-threaded computation which invokes remote services. In this paper game theory is used to analyse the behaviour of orchestration evaluations when underlying web-services are unreliable. Uncertainty profiles are proposed as a means of defining bounds on the number of service failures that can be expected during an orchestration evaluation. An uncertainty profile describes a strategic situation that can be analyzed using a zero-sum angel-daemon game with two competing players: an angel a whose objective is to minimize damage to an orchestration and a daemon d who acts in a destructive fashion. An uncertainty profile is assessed using the value of its angel daemon game. It is shown that uncertainty profiles form a partial order which is monotonic with respect to assessment.

Relevância:

100.00% 100.00%

Publicador:

Relevância:

100.00% 100.00%

Publicador:

Relevância:

100.00% 100.00%

Publicador:

Resumo:

This paper presents a new approach to achieving interoperability between Web-based construction products catalogues. It first introduces the current development of electronic catalogues of construction products. The common system architecture of Web-based electronic products catalogues is discussed, which is followed by a discussion on construction products information standardization and the latest distributed-systems technologies for the communication and exchange of construction products information. The latter part of this paper presents a model of interoperable Web-based construction products catalogue and an implementation of Web services in E-commerce systems to enable the sharing of construction products information.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The construction industry has incurred a considerable amount of waste as a result of poor logistics supply chain network management. Therefore, managing logistics in the construction industry is critical. An effective logistic system ensures delivery of the right products and services to the right players at the right time while minimising costs and rewarding all sectors based on value added to the supply chain. This paper reports on an on-going research study on the concept of context-aware services delivery in the construction project supply chain logistics. As part of the emerging wireless technologies, an Intelligent Wireless Web (IWW) using context-aware computing capability represents the next generation ICT application to construction-logistics management. This intelligent system has the potential of serving and improving the construction logistics through access to context-specific data, information and services. Existing mobile communication deployments in the construction industry rely on static modes of information delivery and do not take into account the worker’s changing context and dynamic project conditions. The major problems in these applications are lack of context-specificity in the distribution of information, services and other project resources, and lack of cohesion with the existing desktop based ICT infrastructure. The research works focus on identifying the context dimension such as user context, environmental context and project context, selection of technologies to capture context-parameters such wireless sensors and RFID, selection of supporting technologies such as wireless communication, Semantic Web, Web Services, agents, etc. The process of integration of Context-Aware Computing and Web-Services to facilitate the creation of intelligent collaboration environment for managing construction logistics will take into account all the necessary critical parameters such as storage, transportation, distribution, assembly, etc. within off and on-site project.

Relevância:

100.00% 100.00%

Publicador:

Relevância:

100.00% 100.00%

Publicador:

Resumo:

OWL-S is an application of OWL, the Web Ontology Language, that describes the semantics of Web Services so that their discovery, selection, invocation and composition can be automated. The research literature reports the use of UML diagrams for the automatic generation of Semantic Web Service descriptions in OWL-S. This paper demonstrates a higher level of automation by generating complete complete Web applications from OWL-S descriptions that have themselves been generated from UML. Previously, we proposed an approach for processing OWL-S descriptions in order to produce MVC-based skeletons for Web applications. The OWL-S ontology undergoes a series of transformations in order to generate a Model-View-Controller application implemented by a combination of Java Beans, JSP, and Servlets code, respectively. In this paper, we show in detail the documents produced at each processing step. We highlight the connections between OWL-S specifications and executable code in the various Java dialects and show the Web interfaces that result from this process.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The widespread use of service-oriented architectures (SOAs) and Web services in commercial software requires the adoption of development techniques to ensure the quality of Web services. Testing techniques and tools concern quality and play a critical role in accomplishing quality of SOA based systems. Existing techniques and tools for traditional systems are not appropriate to these new systems, making the development of Web services testing techniques and tools required. This article presents new testing techniques to automatically generate a set of test cases and data for Web services. The techniques presented here explore data perturbation of Web services messages upon data types, integrity and consistency. To support these techniques, a tool (GenAutoWS) was developed and applied to real problems. (C) 2010 Elsevier Inc. All rights reserved.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Detta arbete har bedrivits i syfte att kartlägga funktionalitet, teknik och användningsområde gällande Web Services. Innehållet utgör således en teoretisk utvärdering av Web Services, samt tester av grundläggande programmeringslösningar. De frågor arbetet ämnar besvara är hur en Web Services på lämpligt sätt kan baseras på en befintlig tjänst, samt på vilket sätt denna Web Services kan göra aktuell tjänst lättare att använda. Dessutom belyses eventuella problem som kan uppstå i samband med denna Web Services-anpassning. I syfte att presentera ett lösningsförslag på ovan nämnda frågor granskades, via en litteraturstudie, ett antal informatikrelaterade begrepp liksom faktorer förknippade med kommersiell verksamhet på Internet. Erhållen teoretisk fakta analyserades via empiriskt arbete. Resultaten av analysen indikerar att en Web Services baserad på karttjänsten MapService kan innebära vissa fördelar för det aktuella företaget såväl som för deras kunder. Att bredda tjänsteutbudet med en marknadsdominerande standard innebär vissa fördelar för ett företag, inte minst i form av ett potentiellt större kundunderlag. Kundens vinster utgörs främst av för ändamålet utformade toolkits. Dessa hjälpmedel och verktyg underlättar implementationen av aktuell tjänst. Den ansats som här valts, att designa Web Servicen som en parser (tolk/konverterare) vars huvudsakliga syfte är att förmedla kommunikation mellan användare och befintlig tjänst, har vissa fördelar. Främst det faktum att redan befintlig funktionalitet kan utnyttjas. All kommunikation mellan användare och server hanteras av Web Servicen, som enligt denna princip utgör ett nytt gränssnitt med vilket tjänsten MapService kan användas. Till följd av det omfattande teoretiska utredningsarbetet har detta arbete inte genererat några prototyper, annat än på ett teoretiskt plan. Det problem som återstår är att utreda exakt hur ovan nämnda parser skall vara utformad, för att sedan implementera all funktionalitet som en helhet.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Service-based architectures enable the development of new classes of Grid and distributed applications. One of the main capabilities provided by such systems is the dynamic and flexible integration of services, according to which services are allowed to be a part of more than one distributed system and simultaneously serve different applications. This increased flexibility in system composition makes it difficult to address classical distributed system issues such as fault-tolerance. While it is relatively easy to make an individual service fault-tolerant, improving fault-tolerance of services collaborating in multiple application scenarios is a challenging task. In this paper, we look at the issue of developing fault-tolerant service-based distributed systems, and propose an infrastructure to implement fault tolerance capabilities transparent to services.