Research on Web service discovery based on domain ontology

Web services are the new paradigm for distributed computing. They offer interoperability of application and integration of large scale distributed systems. Amongst the web service standards, service registry is crucial to the overall utility of web service technology. However, the web services discovery mechanism pertaining with the UDDI [1] registry is inefficient because it only supports keyword-based and category-based matching, leading to irrelevant matches. Therefore, the provision of the scalable, flexible and robust web services publication and discovery system is crucial for the overall utility of web services. In this paper, we develop a scalable, robust and efficient infrastructure for web services publication and discovery amongst domain-based registries. More importantly, a novel algorithm is provided to classify web services into domain-based registries based on their semantic description. Experimental results show that our approach outperforms a centralized approach in terms of service discovery time.

Semantic Web Service technology provides a strong support for automation software development based on Web service. By analyzing the existing description models and methods of semantic Web service, a Semantic Web Service Description Model (WSDM4S) and its formal description based on SHOIN+(D) are proposed, which attempt to offer an effective model for description, publication, discovery, composition, and execution of Web services based on semantic description. And a Semantic Web Service Description Language (WSDL4S) based on XML is designed to support the WSDM4S. Based on WSDL4S, Web Services could be packaged into basic semantic unit of semantic software development.

The Web service infrastructure has been an important software component on the Internet. A critical step in Web service applications is the service discovery method. The structured information in the web services description language (WSDL) of a Web service is unsuitable when using the traditional information retrieval (IR) method. We propose a Web service discovery method that is based on extracting information from WSDL documents. The method employs data segmentation to analyze the information to a meaningful structure where the traditional IR techniques can be applied. Furthermore, WordNet has been exploited in this method to carry out a synonym search. The experiments show that our method represents a significant improvement in the performance of Web service discovery.

Main challenges to the current semantic web service technologies are exponential continuous growth in the number of services on the Internet, syntax based discovery, lack of common agreed upon semantic service standards and heterogeneity of ontologies. In this paper, a service discovery approach independent of semantic service description models is proposed to solve the challenges of the current web service discovery. The idea is to combine principles from machine learning, data mining, statistical techniques and measures of semantic relatedness to make the semantic web service discovery process more intelligent, efficient and effective. The proposed approach exploits the use of semantic as well as syntactic information present within the service description profiles. Our approach is unique in terms of its application to any web service description language and the use of Omiotis measure of semantic relatedness for service discovery. The proposed approach has been implemented on OWL-S based service descriptions profiles and is able to find semantic relationship between the services which were otherwise discarded by the OWL-MX matchmaker. Empirical analysis shows that the proposed method out performs the

Web services as a new distributed system technology have been widely adopted by industries in the areas, such as enterprise application integration (EAI), business process management (BPM), and virtual organization (VO). However, lack of semantics in the current Web service standards has become a major barrier in service discovery and composition. To tackle the semantic issues of Web services, this paper proposes a comprehensive semantic service description framework – CbSSDF and a two-step service discovery mechanism based on CbSSDF—to help service users to easily locate their required services. The authors give a detailed explanation of CbSSDF, and then evaluate the framework by comparing it with OWL-S to examine how the proposed framework can improve the efficiency and effectiveness of service discovery and composition. The evaluation is carried out by analysing the different proposed solutions based on these two frameworks for achieving a series of tasks in a scenario.

Web services are becoming the most important paradigm for distributed computing and electronic business. They are self-contained Internet accessible applications that are capable not only of performing business activities on their own, but they also possess the ability to engage with other Web services in order to build new value-added services. In this paper we present a work that focuses on the issue of automated service discovery in conjunction with the Semantic Web. To get this aim, we propose an approach which exploits the service interface (inputs/outputs) and the domain ontology, in order to model the web services, after that, we compute a similarity score between the request and the modeled web services through a matching algorithm. This later is based on the wu&palmer's similarity measure. A test based on the OWLTC collection is shown to elucidate the system functioning.

In recent years, the web service is becoming more and more popular in various application domains, which attracts many researchers to contribute their efforts. Service searching is one of the fundamental topics in service-oriented applications. In traditional service matchmaking, most approaches uses keyword-based methods for service discovery that may cause difficulties in meeting users' demands precisely. In order to address the above problem, we propose, in this work, a web service discovery method that combines WordNet and domain ontologies, which could improve the quality and precision of the discovered web services by using semantic web technologies.

SGrid: a service-oriented model for the Semantic Grid

Web services – a new breed of self-contained, self-describing, modular applications published, located, and invoked across the Web – handle functions, from simple requests to complicated business processes. They are defined as network-based application components with a services-oriented architecture (SOA) using standard interface description languages and uniform communication protocols. SOA enables organizations to grasp and respond to changing trends and to adapt their business processes rapidly without major changes to the IT infrastructure. The Inaugural International Conference on Next-Generation Web Services Practices (NWeSP'05) attracted researchers who are also the world's most respected authorities on the semantic Web, Web-based services, and Web applications and services. NWeSP'05 was held in cooperation with the IEEE Computer Society Task Force on Electronic Commerce, the Technical Committee on Internet, and the Technical Committee on Scalable Computing. This special issue presents eight papers focused on different aspects of Web services and their applications. Papers were selected based on fundamental ideas and concepts rather than the thoroughness of techniques employed. Papers are organized as follows: <I>Taher et al.</I> present the first paper, on a Quality of Service Information and Computational framework (QoS-IC) supporting QoS-based service selection for SOA. The framework's functionality is expanded using a QoS constraints model that establishes an association relationship between different QoS properties and is used to govern QoS-based service selection in the underlying algorithm. Using a prototype implementation, the authors demonstrate how QoS constraints improve QoS-based service selection and save consumers valuable time. Due to the complex infrastructure of web applications, response times perceived by clients may be significantly longer than desired. To overcome some of the current problems, <I>Vilas et al.</I>, in the second paper, propose a cache-based extension of the architecture that enhances the current web services architecture, which is mainly based on program-logic or protocol-dependent optimization. In the third paper, Jo and Yoo present authorization for securing XML sources on the Web. One of the disadvantages of existing access control is that the DOM tree must be loaded into memory while all XML documents are parsed to generate the DOM tree, such that a lot of memory is used in repetitive search for tree to authorize access to all nodes in the DOM tree. The complex authorization evaluation process required thus lowers system performance. Existing access control fails to consider information structure and semantics sufficiently due to basic HTML limitations. The authors overcome some of these limitations in the proposed model. In the fourth paper, Jung and Cho propose a novel behavior-network-based method for Web service composition. The behavior network selects services automatically through internal and external links with environmental information from sensors and goals. An optimal service is selected at each step, resulting in a globally optimal service sequence for achieving preset goals. The authors detail experimental results for the proposed model by comparing them with rule-based system and user tests. <I>Kong et al.</I> present an efficient method in the fifth paper for merging heterogeneous ontologies – no ontology building standard currently exists – and the many ontology-building tools available are based on different ontology languages, mostly focusing on how to create, edit and infer the ontology efficiently. Even ontologies about the same domain differ because ontology experts hold different view points. For these reasons, interoperability between ontologies is very low. The authors propose merging heterogeneous domain ontologies by overcoming some of the above limitations. In the sixth paper, Chen and Che provide polynomial-time tree pattern query minimization algorithm whose efficiency stems from two key observations: (i) Inherent redundant "components" usually exist inside the rudimentary query provided by the user, and (ii) nonedundant nodes may become redundant when constraints such as co-occurrence and required child/descendant are given. They show that the algorithm obtained by first augmenting the input tree pattern using constraints, then applying minimization, invariably finds a unique minimal equivalent to the original query. Chen and Che present a polynomial-time algorithm for tree pattern query (TPQ) minimization without XML constraints in the seventh paper. The two-part algorithm is a dynamic programming strategy for finding all matching subtrees within a TPQ. The algorithm consists of one for subtree recognization and a second for subtree deletion. In the last paper, <I>Bagchi et al.</I> present the mobile distributed virtual memory (MDVM) concept and architecture for cellular networks containing server-groups (SG). They detail a two-round randomized distributed algorithm to elect a unique leader and co-leader of the SG that is free of any assumption about network topology, and buffer space limitations and is based on dynamically elected coordinators eliminating single points of failure. As guest editors, we thank all authors featured in this special issue for their contributions and the referees for critically evaluating the papers within the short time allotted. We sincerely believe that readers will share our enjoyment of this special issue and find the information it presents both timely and useful.

Ontology method has become an important method in computer science, and it has been used in many domains, such as semantic web, search engine and knowledge management. Ontology plays an important role in semantic retrieval because of its specification, its good concept hierarchy and its support for logical reasoning. Domain ontology can be used to extend the user’s retrieval words and index domain knowledge. Under which we can achieve semantic retrieval for domain knowledge. The semantic extension of user’s retrieval words is the more important step in semantic retrieval system. First, this paper designed the model of semantic query expansion based on domain ontology and gave five kinds of semantic expansion methods. Then the model of semantic query expansion is applied in semantic retrieval system. The designed system consists of four main components: ontologies building, retrieval words semantic extension, semantic precomputation for document and semantic retrieval. Finally, this paper makes an experiment on high-speed railway domain. The experimental results show that the developed semantic retrieval system can improve the recall and precision.

In this paper, we propose a WebSIS which provides various semantic information services based on Web service and ontology for grid computing environment. The prototype of WebSIS provides resource information service for resource discovery, resource matching and resource monitoring, in order to allocate appropriate resource for user task. Since WebSIS creates a virtual organization by defining a resource pool which consists of ontology instance data, it can build a extensible and scalable resource pool dynamically by creating and deleting ontology instance data for each resource. Moreover, the hierarchical structure of ontology and the separate description of schema, instance and rule enables users to build flexible and extensible knowledge base for various domains. We present an extensible and flexible architecture of WebSIS which can efficiently create a new information service and can easily add a new ontology domain. It allows users to build a manifold and reliable information processing service by enabling the incorporation of various semantic ontologies for the inference of semantic information. Moreover, it provides reliability and accurate resource related service by using dynamic resource information obtained through resource agent. We shall show how the semantic information service for resource discovery, resource matching and resource monitoring is carried out in WebSIS.

The semantic web promises automates invocation, discovery and composition of web services by enhancing services with semantic descriptions. This paper describes a model driven approach to facilitate the construction of OWL-S specifications. The methodology is divided into three main steps. In the first step we reverse engineered WSDL documents into UML profile models that enable the use of high-level graphical models as an integration platform for semantic web services. In the second step, suitable domain ontologies are used for the semantic annotation of the UML models. Finally, in the third step a conversion tool will generate automatically the OWL-S description from these UML models. The UML profile provides flexibility as it can expresses multiple semantic web service concepts.

Currently, Web services have been identified as the salient technology in providing a flexible solution for interoperating the heterogeneous application systems. Due to the dramatic increasing number of available Web services, how to discover the relevant services dispersed over a number of service providers is a big challenge. Although, the current service discovery mechanism can be achieved through the public UDDI, the UDDI structure is not powerful enough for computer-interpretation to enable automatic Web service discovery. This research proposes the layered-architecture of semantic service discovery system by incorporating search crawler as a core component for discovering services resided on the provider websites. The search crawler can operate in multi-threaded environment to enhance the capability of discovering a number of distributed Web services simultaneously, as well as in various UDDI registries. In order to enrich service discovery in a semantic manner, the Web services descriptions returned from the search crawlers are thus modeled into a machine-processable representation language such as OWL-S. The system conformed to the proposed architecture will provide the flexibility and extensibility to accomplish complex Web service requests that meet user-specified functional requirements.

Every business or government agency needs to track information regarding their finances, their employees, and the items or assets they own and manage. Software applications that track this type of information are called enterprise resource planning (ERP) systems. Managing these assets in an integrated application allows an organization to have a consistent view across the entire enterprise. This enterprise-wide view allows ERP systems to go beyond the traditional transaction-based accounting systems maintained at the organization level and deliver fully integrated financial and human capital management based on industry-derived best practices across organizations. In response to the pressures of global competition, enterprises today are forging ahead with the mission of integrating information systems across corporate boundaries to unite customers, suppliers and any other business partners with which they interact. And in the mean time, with the development of the society, more and more people have to go many places because the job makes them and working at home also becomes more and more popular. Those people who are not at the place of their company also want to continue their work in other places even at home. The old style ERP system is in C/S model and cannot satisfy with the needs. So it is very necessary to upgrade the ERP system. This paper will go to figure out the application of the Web service in the upgrading of ERP system. In this paper, we focus on that how to upgrade or renew a C/S ERP system to an ERP system with B/S model and the application of Web service. We use the J2EE architecture and XML technology to provide Web service and upgrade/renew the former ERP system. UML tools play a very important role in the upgrading procedure. We use UML to analysis and design the B/S ERP system, which based on the C/S version. We use JSP to act as the view of the system because of its flexibility. In the Web service, the XML is necessary. So the XML technology is also used. In the end of the paper, we will figure out how these technologies to be used through a concrete example.

Existing approaches to Semantic Web Services (SWS) require a domain ontology and a semantic description of the service. In the case of lightweight SWS approaches, such as SAWSDL, service description is achieved by semantically annotating existing web service interfaces. Other approaches such as OWL-S and WSMO describe services in a separate ontology. So, existing approaches separate service description from domain description, therefore increasing design efforts. We propose EXPRESS a lightweight approach to SWS that requires the domain ontology definition only. Its simplicity stems from the similarities between REST and the Semantic Web such as resource realization, self describing representations, and uniform interfaces. The semantics of a service is elicited from a resource's semantic description in the domain ontology and the semantics of the uniform interface, hence eliminating the need for ontologically describing services. We provide an example that illustrates EXPRESS and then discuss how it compares to SA-REST and WSMO.