Shuai Yuan

Comparison of Bio-inspired Algorithms for Peer Selection in Services Composition

One of the challenges for the P2P-based service composition process is how to effectively discover and select the most appropriate peers to execute the service applications when considering multiple properties of the requested services. Different ontology-based e-service profiles have been proposed to facilitate handling multiple properties and to enhance the service oriented process in order to achieve the total or partial automation of service discovery, selection and composition. This paper investigates how the ACO (Ant Colony Optimisation) algorithm and the GA (Genetic Algorithm) may facilitate P2P-based (Peer-to-Peer) service selection with multiple service properties. The performance of both algorithms is evaluated and compared statistically using a pooled t-test for 30 randomly generated composition scenarios. Our experimental results show that both algorithms can improve the quality of service composition, while showing that the ACO approach is the more effective.

A Pragmatic GIS-Oriented Ontology for Location Based Services

With advances in automatic position sensing and wireless connectivity, location-based services (LBS) are rapidly developing, particularly in fields of geographic, tourism and logistic information systems. Currently, Web service has been viewed as one of most significant innovations in business industry, and designed on demand to provide spatial related information for LBS consumption. However, the traditional Web Service Description Language (WSDL) cannot meet those requirements, as WSDL is not able to support semantic content and information. In recent years, Ontology came up with an effective approach to enhance service description, automated discovery, dynamic composition, enactment, and other tasks such as managing and using service-based systems. In this paper, we propose geographic ontology based on Geography Markup Language (GML) and extend OWL-S profile to form geographic profile. Web service, which is advertised on the basis of our GeoProfile, contains geographic information inherently.

QoS-aware peer services selection using ant colony optimisation

Web services coordinated by computational peers can be aggregated to create composite workflows that provide streamlined functionality for human users or other systems. One of the most critical challenges introduced by Peer-to-Peer (P2P) based Web services is represented by Quality of Service (QoS)-driven services composition. Since many available Peers provide overlapping or identical functionalities, though with different QoS, selections need to be quickly made to determine which peers are suitable to participate in an expected composite service. The main contribution of this paper is a heuristic approach which effectively and adaptively finds appropriate service peers for a service workflow composition, and also some uncertainties in the real ad-hoc scenarios are considered by a proper re-planning scheme. We propose to adopt Ant Colony Optimisation (ACO) to tackle the QoS-aware Peers’ composition problem in both static and dynamic situations, as ACO represents a more scalable choice, and is suitable to handle and balance generic QoS attributes by pheromones. The proposed approach is able to improve the selection performances in various service composition structures, and also can adaptively handle unexpected events. We present experimental results to illustrate the efficiency and feasibility of the proposed method.

Mining e‐services in P2P‐based workflow enactments

Purpose – This paper aims to explore the feasible mining and proper selection of QoS‐aware services for a P2P‐based business process enactment framework, and enhance the relevant workflow prototype. Design/methodology/approach – Through observing and analysing unpredictable dynamic changes that commonly exist in e‐service workflow, a set of QoS specifications and monitoring mechanisms in a P2P workflow framework is proposed. These specifications are an evolving extension of services description with semantic web facilitators for P2P‐based e‐services.Findings – It has been demonstrated that the QoS‐OWL approach can be effectively used to describe and exploit e‐services, particularly in a decentralised environment. QoS‐OWL is also able to provide the deliberation of geographic information for e‐services, and facilitates the peers effective cooperation and automates business processes. It is recommended that the approach be adopted in the dynamic online information system environment to increase efficiency...

Ant Inspired Scalable Peer Selection in Ontology-Based Service Composition

This work focuses on proposing a method of effectively dealing with P2P-based service selection and composition, especially when handling a large number of Peers along with their diverse qualities. The QoS-aware Peer selection is one of the major challenges faced in order to guarantee the success and enhance performance of distributed computing. Since many Peer candidates provide overlapping or identical functionalities, though with different QoS evaluations, selections need to be rapidly conducted to determine which Peers are suitable to join in the requested composite service. The main contribution of this paper is proposing a P2P-based service selection model, in which Peer’s non-functional properties are modeled with Web Service Modelling Ontology (WSMO), and where Ant Colony Optimisation (ACO) technique is adopted to facilitate and enhance the QoS-aware Peers’ composition. We present experimental results to illustrate the effectiveness and feasibility of the proposed method.

QoS-Aware Service Selection in P2P-Based Business Process Frameworks

With the advances and evolution of semantic Web services, service providers need to be more competitive, efficient, flexible, and integrated in the service network at different scenarios, including static and dynamic deployments and interactions. Recently, OWLS and QoS-aware services have been distinguished due to their significance and their impact on decentralised network. JXTA and BPEL allow peers to cooperate and automate business processes and reengineer their structure, so as to rationally select and make use of all resource in decentralised environment; in addition, they increase efficiency and reduce costs. We incorporated several typical constraints to testify the possibility of the application of QoS-aware services in a P2P network, and enhanced the performance of the relevant prototype.

A Practical Geographic Ontology for Spatial Web Services

The application of ontology in Web services context for dynamic discovery, autonomous composition, invocation and monitoring has been deemed as very promising in semantic Web based enterprise application integration and m-commerce. There are many initiatives aiming to realize pervasive services to enable effective enactment of better quality of services, such as sensitiveness on service locations. The traditional WSDL is hardly qualified enough to tackle new challenges such as accurate representation of the non-functional properties of services. Hence, OWL-S came up with an effectual approach to facilitating semantic service description, dynamic composition, on-the-fly execution, and many other tasks. In this paper, we propose a practical geographic ontology based on geography markup language (GML) and extend OWL-S profile to formulate new geographic profiles. We also discuss specific scenarios where context-aware services invocation peers, which are advertised and coordinated via a newly designed GeoProfile, can be equipped with geographic information inherently to distinguish different peers.

Adaptive E-Services Selection in P2P-Based Workflow with Multiple Property Specifications

P2P (Peer-to-Peer) based service computing has emerged as an important new field in the distributed computing arena. It focuses on intensive service sharing, innovative applications and compositions, and in some cases, high performance orientation. However, the main challenge for P2P-based service composition process is how to intelligently mining and selection the most appropriate peers to execute the service application in complex and dynamic situations. Traditional methodologies are still very inadequate to effectively and autonomously conduct the service mining and selection in a real-time environment, as they seldom consider and focus on dealing with complex situations, such as simultaneously considering peers’ multiple specifications which reflect different properties of e-services. Different ontology based e-service profiles have been proposed to enhance service oriented framework for the total or partial automation of service mining, selection and composition, which are involved in either centralised or decentralised deployment of services. In this chapter, we propose a modelling based approach to design and develop a P2P based service coordination system and their components. The peer profiles are described with the WSMO (Web Service Modelling Ontology) standard, mainly for quality of service and geographic features of the e-services, which would be invoked by various peers. To fully explore the usability of service categorisation and mining, we implemented an ontology driven unified algorithm to select the most appropriate peers. The UOW-SWS prototype also shows that the enhanced peer coordination is more adaptive and effective in dynamic business processes.

Dynamic Selection of Service Peers with Multiple Property Specifications

Semantic Web services, one of the most significant areas in the emerging business process management systems, have attracted a great deal of effort from both academic and industry community. Traditional methodologies are still very inadequate to effectively and autonomously conduct service discovery and composition in a dynamic environment, as they seldom focus on dealing with real complex situations, such as simultaneously considering peers’ multiple specifications which reflect different properties of e-services. Different ontology based e-service profiles have been proposed to enhance service oriented framework for the total or partial automation of service invocation, discovery, selection and composition, which are involved in either centralised or decentralised deployment of services. In this paper, we propose a modelling based approach to design and develop a peer-to-peer based service coordination system and their components. The peer profiles are described with the WSMO (Web Service Modelling Ontology) standard, mainly for quality of service and geographic features of the e-services, which would be invoked by various peers. To fully explore the usability of service categorisation and mining, we implemented an ontology driven unified algorithm to select the most appropriate peers. The UOW-SWS prototype also shows that the enhanced peer coordination is more adaptive and effective in dynamic business processes.

Adaptive Task Allocation for P2P-Based e-Services Composition

To effectively manage the task allocation, especially when handling with numerous different peers qualities, is one of the greatest challenges to be faced in order to guarantee the success of P2P-based e-services composition. In this context, various QoS descriptive frameworks and Web services technologies (such as WSDL and BPEL) are being considered as the most affordable solutions to promote the performance of decentralized e-services, through applying strategies like QoS ontologies and related optimization algorithms globally or locally. Nonetheless, most P2P-based service selection and composition approaches applied nowadays lack dynamism and autonomy. In this paper, we first propose an extension of non-functional properties in WSMO, so that to globally facilitate dynamism and autonomous coordination in service compositions. Furthermore, taking into account a model driven approach, we design a planning algorithm to intelligently assign composition tasks to the most appropriate peers for different steps in a whole process. This algorithm is implemented in our prototype UOW-SWS via considering a typical LoanApproval scenario.