Semantic web service discovery approaches: overview and limitations
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paper_title: Efficient and adaptive discovery techniques of Web Services handling large data sets

paper_content:

Attempts have been made concerning the search and finding of a Web Service based on keywords and descriptions. However, no work has been done concerning the efficient selection of the appropriate Web Service instance in terms of quality and performance factors at the moment of the Web Service consumption attempt. Such factors may include execution time and response time. The proposed approach adaptively selects the most efficient WS among possible different alternatives with real-time, optimized and countable factors-parameters. Implementation issues and case study experiments are presented along with the corresponding results. Additionally, an optimal selection algorithm for series of Web Services requests is proposed. Finally, conclusions and future steps are discussed.
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paper_title: Coupled Signature and Specification Matching for Automatic Service Binding

paper_content:

Matching of semantic service descriptions is the key to automatic service discovery and binding. Existing approaches split the matchmaking process in two step: signature and specification matching. However, this leads to the problem that offers are not found although they are functionally suitable if their signature is not fitting the requested one. Therefore, in this paper, we propose a matching algorithm that does not use a separated and explicit signature matching step, but derives the necessary messages from the comparison of pre- and postconditions. As a result, the algorithm not only finds all functionally suitable services even if their signatures do not match, but also is able to derive the messages needed for an automatic invocation.
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paper_title: Imprecise RDQL: towards generic retrieval in ontologies using similarity joins

paper_content:

Traditional semantic web query languages support a logic-based access to the semantic web. They offer a retrieval (or reasoning) of data based on facts. On the traditional web and in databases, however, exact querying often provides an incomplete answer as queries are overspecified or the mix of multiple ontologies/modelling differences requires "interpretational flexibility." Therefore, similarity measures or ranking approaches are frequently used to extend the reach of a query. This paper extends this idea to the semantic web. It introduces iRDQL---a semantic web query language with support for similarity joins. It is an extension of traditional RDQL (RDF Data Query Language) that enables the users to query for similar resources ranking the results using a similarity measure. We show how iRDQL allows to extend the reach of a query by finding additional results. We quantitatively evaluated four similarity measures for their usefulness in iRDQL in the context of an OWL-S semantic web service retrieval test collection and compared the results to a specialized OWL-S matchmaker. Initial results of iRDQL indicate that it is indeed useful for extending the reach of queries and that it is able to improve recall without overly sacrificing precision. We also found that our generic iRDQL approach was only slightly outperformed by the specialized algorithm.
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paper_title: Semantic Service Discovery with DIANE Service Descriptions

paper_content:

In this paper, we introduce the DIANE Service Description (DSD) and show how it has been used to solve the discovery problems stated in the scenarios of the SWSChallenge 1 . We provide a consolidated description of our approach that we presented at the first four SWS-Challenge workshops and briefly discuss its strengths and drawbacks.
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paper_title: CASCOM: Intelligent Service Coordination in the Semantic Web

paper_content:

This book presents the design, implementation and validation of a value-added supportive infrastructure for Semantic Web based business application services across mobile and fixed networks, applied to an emergency healthcare application. This infrastructure has been realized by the CASCOM European research project. For end users, the CASCOM framework provides seamless access to semantic Web services anytime, anywhere, by using any mobile computing device. For service providers, CASCOM offers an innovative development platform for intelligent and mobile business application services in the Semantic Web. The essential approach of CASCOM is the innovative inter-disciplinary combination of intelligent agent, Semantic Web, peer-to-peer, and mobile computing technology. Conventional peer-to-peer computing environments are extended with components for mobile and wireless communication. Semantic Web services are provided by peer software agents, which exploit the coordination infrastructure to efficiently operate in highly dynamic environments. The generic coordination support infrastructure includes efficient communication means, support for context-aware adaptation techniques, as well as flexible, resource-efficient service discovery, execution, and composition planning. The book has three main parts. First, the state-or-the-art is reviewed in related research fields. Then, a full proof-of-concept design and implementation of the generic infrastructure is presented. Finally, quantitative and qualitative analysis is presented on the basis of the field trials of the emergency application.
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paper_title: What is needed for semantic service descriptions? A proposal for suitable language constructs

paper_content:

The big promise of service-oriented computing is the ability to form agile networks. Agile networks are networks of loosely coupled participants that cooperate by dynamically discovering and invoking each other's services at run-time. The major prerequisite for this promise to be fulfilled is an appropriate semantic service description. In this paper, we identify requirements towards such a service description language and show that neither of the two main current approaches, OWL-S and WSMO, is able to fully meet these requirements. We then proceed to suggest additional language constructs and a prototypical language, the DIANE Service Description (DSD), which implements these constructs. We explain how service offers and requests can be described and matched using DSD.
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paper_title: Large-Scale Information Retrieval with Latent Semantic Indexing

paper_content:

Abstract As the amount of electronic information increases, traditional lexical (or Boolean) information retrieval techniques will become less useful. Large, heterogeneous collections will be difficult to search since the sheer volume of unranked documents returned in response to a query will overwhelm the user. Vector-space approaches to information retrieval, on the other hand, allow the user to search for concepts rather than specific words, and rank the results of the search according to their relative similarity to the query. One vector-space approach, Latent Semantic Indexing (LSI), has achieved up to 30% better retrieval performance than lexical searching techniques by employing a reduced-rank model of the term-document space. However, the original implementation of LSI lacked the execution efficiency required to make LSI useful for large data sets. A new implementation of LSI, LSI++, seeks to make LSI efficient, extensible, portable, and maintainable. The LSI++ Application Programming Interface (API) allows applications to immediately use LSI without knowing the implementation details of the underlying system. LSI++ supports both serial and distributed searching of large data sets, providing the same programming interface regardless of the implementation actually executing. In addition, a World Wide Web interface was created to allow simple, intuitive searching of document collections using LSI++. Timing results indicate that the serial implementation of LSI++ searches up to six times faster than the original implementation of LSI, while the parallel implementation searches nearly 180 times faster on large document collections.
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paper_title: DIANE: A Matchmaking-Centered Framework for Automated Service Discovery, Composition, Binding, and Invocation on the Web

paper_content:

Service-oriented computing will allow for the automatic discovery, composition, binding, and invocation of Web services. The single most important component of this goal is appropriate matchmaking. This paper presents a service-description language and its associated matchmaking algorithms. Together they precisely capture requester preferences through fuzzy sets, express and use instance information for matchmaking, and deal efficiently with multiple effects. The approach described here has been extensively evaluated both in experiments and in the 2006 Semantic Web Services Challenge.
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paper_title: Jensen-Shannon divergence and Hilbert space embedding

paper_content:

This paper describes the Jensen-Shannon divergence (JSD) and Hilbert space embedding. With natural definitions making these considerations precise, one finds that the general Jensen-Shannon divergence related to the mixture is the minimum redundancy, which can be achieved by the observer. The set of distributions with the metric /spl radic/JSD can even be embedded isometrically into Hilbert space and the embedding can be identified.
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paper_title: TOP-K cosine similarity interesting pairs search

paper_content:

Recent years have witnessed an increased interest in computing cosine similarities between documents (or commodities). Most previous studies require the specification of a minimum similarity threshold to perform cosine similarity search. However, it is usually difficult for users to provide an appropriate threshold in practice. Instead, in this paper, we propose to search top-K strongly related pairs of objects as measured by the cosine similarity. Specifically, we first define the cosine similarity measure from the association analysis point of view and identify the monotone property of an upper bound of the cosine measure, then exploit a diagonal traversal strategy for developing the TOP-DATA and TOP-DATA-R algorithms. Finally, experimental results demonstrate the computational efficiencies of above algorithms.
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paper_title: Agent approach for service discovery and utilization

paper_content:

There is an extensive set of published and usable services on the Internet. Human based approaches to discover and utilize these services is not only time consuming, but also requires continuous user interaction. This paper describes an agent approach for service discovery and utilization (AASDU), which focuses on using light weight autonomous agents built into a multi-agent referral community, and Web service standards (namely UDDI, SOAP, WSDL and XML). The AASDU approach proposes to use agents that interact with end users by accepting their queries to discover services, and efficiently manage service invocation. AASDU uses intrinsic multi-agent properties to allow agents to communicate and cooperate with one another. Each agent conforms to a communication protocol that allows it to send and receive messages from another agent, without needing to know the address of the receiving agent. There is a need for effective and efficient communication among components in a multi-disciplinary, cross-organizational architecture. This has resulted in a proliferation of communication building blocks, or middleware, for distributed scientific computing. The most recent, and quite network-based services, referred to as Web services. This paper also discusses the interoperability that can be achieved between software components through the use of Web service standards and protocols in the context of AASDU.
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paper_title: Two-phase Web Service Discovery based on Rich Functional Descriptions

paper_content:

Discovery is a central reasoning task in service-oriented architectures, concerned with detecting Web services that are usable for solving a given request. This paper presents two extensions in continuation of previous works towards goal-based Web service discovery with sophisticated semantic matchmaking. At first, we distinguish goal templates as generic objective descriptions and goal instances that denote concrete requests as an instantiation of a goal template. Secondly, we formally describe requested and provided functionalities on the level of state transitions that denote executions of Web services, respectively solutions for goals. Upon this, we specify a two-phase discovery procedure along with semantic matchmaking techniques that allow to accurately determine the usability of a Web service. The techniques are defined in the Abstract State Space model that supports several languages for describing Web services.
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paper_title: CASCOM: Intelligent Service Coordination in the Semantic Web

paper_content:

This book presents the design, implementation and validation of a value-added supportive infrastructure for Semantic Web based business application services across mobile and fixed networks, applied to an emergency healthcare application. This infrastructure has been realized by the CASCOM European research project. For end users, the CASCOM framework provides seamless access to semantic Web services anytime, anywhere, by using any mobile computing device. For service providers, CASCOM offers an innovative development platform for intelligent and mobile business application services in the Semantic Web. The essential approach of CASCOM is the innovative inter-disciplinary combination of intelligent agent, Semantic Web, peer-to-peer, and mobile computing technology. Conventional peer-to-peer computing environments are extended with components for mobile and wireless communication. Semantic Web services are provided by peer software agents, which exploit the coordination infrastructure to efficiently operate in highly dynamic environments. The generic coordination support infrastructure includes efficient communication means, support for context-aware adaptation techniques, as well as flexible, resource-efficient service discovery, execution, and composition planning. The book has three main parts. First, the state-or-the-art is reviewed in related research fields. Then, a full proof-of-concept design and implementation of the generic infrastructure is presented. Finally, quantitative and qualitative analysis is presented on the basis of the field trials of the emergency application.
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paper_title: A System Architecture for Context-Aware Service Discovery

paper_content:

Recent technological advances have enabled both the consumption and provision of mobile services (m-services) by small, portable, handheld devices. However, mobile devices still have restricted capabilities with respect to processing, storage space, energy consumption, stable connectivity, bandwidth availability. In order to address these shortcomings, a potential solution is context-awareness (by context we refer to the implicit information related both to the requesting user and service provider that can affect the usefulness of the returned results). Context plays the role of a filtering mechanism, allowing only transmission of relevant data and services back to the device, thus saving bandwidth and reducing processing costs. In this paper, we present an architecture for context-aware service discovery. We describe in detail the system implementation and we present the system evaluation as a tradeoff between a) the increase of the quality of service discovery when context-awareness is taken into account and b) the extra cost/burden imposed by context management.
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paper_title: Evaluating Semantic Web Service Matchmaking Effectiveness Based on Graded Relevance

paper_content:

Semantic web services (SWS) promise to take service oriented computing to a new level by allowing to semi-automate time-consuming programming tasks. At the core of SWS are solutions to the problem of SWS matchmaking, i.e., the problem of comparing semantic goal descriptions with semantic offer descriptions to determine services able to fulfill a given request. Approaches to this problem have so far been evaluated based on binary relevance despite the fact that virtually all SWS matchmakers support more fine-grained levels of match. In this paper, a solution to this discrepancy is presented. A graded relevance scale for SWS matchmaking is proposed as are measures to evaluate SWS matchmakers based on such graded relevance scales. The feasibility of the approach is shown by means of a preliminary evaluation of two hybrid OWL-S matchmakers based on the proposed measures.
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paper_title: Semantic Matching of Web Services Capabilities

paper_content:

The Web is moving from being a collection of pages toward a collection of services that interoperate through the Internet. The first step toward this interoperation is the location of other services that can help toward the solution of a problem. In this paper we claim that location of web services should be based on the semantic match between a declarative description of the service being sought, and a description of the service being offered. Furthermore, we claim that this match is outside the representation capabilities of registries such as UDDI and languages such as WSDL.We propose a solution based on DAML-S, a DAML-based language for service description, and we show how service capabilities are presented in the Profile section of a DAML-S description and how a semantic match between advertisements and requests is performed.
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paper_title: Automatic location of services

paper_content:

The automatic location of services that fulfill a given need is a key step towards dynamic and scalable integration. In this paper we present a model for the automatic location of services that considers the static and dynamic aspects of service descriptions and identifies what notions and techniques are useful for the matching of both. Our model presents three important features: ease of use for the requester, efficient pre-filtering of relevant services, and accurate contracting of services that fulfill a given requester goal. We further elaborate previous work and results on Web service discovery by analyzing what steps and what kinds of descriptions are necessary for efficient and usable automatic service location. Furthermore, we analyze intuitive and formal notions of match that are of interest for locating services that fulfill a given goal. Although having a formal underpinning, the proposed model does not impose any restrictions on how to implement it for specific applications, but proposes some useful formalisms for providing such implementations.
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paper_title: Semantic Web Service Discovery in the OWL-S IDE

paper_content:

The increasing availability of web services necessitates efficient discovery and execution framework. The use of xml at various levels of web services standards poses challenges to the above process. OWL-S is a service ontology and language, whose semantics are based on OWL. The semantics provided by OWL support greater automation of service selection, invocation, translation of message content between heterogeneous services, and service composition. The development and consumption of an OWL-S based web service is time consuming and error prone. OWL-S IDE assists developers in the semantic web service development, deployment and consumption processes. In order to achieve this the OWL-S IDE uses and extends existing web service tools. In this paper we will look in detail at the support for discovery for semantic web services. We also present the matching schemes, the implementation and the results of performance evaluation.
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paper_title: Towards P2P-Based Semantic Web Service Discovery with QoS Support

paper_content:

The growing number of web services advocates distributed discovery infrastructures which are semantics-enabled and support quality of service (QoS). In this paper, we introduce a novel approach for semantic discovery of web services in P2P-based registries taking into account QoS characteristics. We distribute (semantic) service advertisements among available registries such that it is possible to quickly identify the repositories containing the best probable matching services. Additionally, we represent the information relevant for the discovery process using Bloom filters and pre-computed matching information such that search efforts are minimized when querying for services with a certain functional/QoS profile. Query results can be ranked and users can provide feedbacks on the actual QoS provided by a service. To evaluate the credibility of these user reports when predicting service quality, we include a robust trust and reputation management mechanism.
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paper_title: Making the Difference: A Subtraction Operation for Description Logics

paper_content:

Abstract We define a new operation in description logics, the difference operation or subtraction operation. This operation allows to remove from a description as much as possible of the information contained in another description. We define the operation independently of a specific description logic. Then we consider its implementation in several specific logics. Finally we describe practical applications of the operation.
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paper_title: Coupled Signature and Specification Matching for Automatic Service Binding

paper_content:

Matching of semantic service descriptions is the key to automatic service discovery and binding. Existing approaches split the matchmaking process in two step: signature and specification matching. However, this leads to the problem that offers are not found although they are functionally suitable if their signature is not fitting the requested one. Therefore, in this paper, we propose a matching algorithm that does not use a separated and explicit signature matching step, but derives the necessary messages from the comparison of pre- and postconditions. As a result, the algorithm not only finds all functionally suitable services even if their signatures do not match, but also is able to derive the messages needed for an automatic invocation.
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paper_title: The Field Matching Problem: Algorithms and Applications

paper_content:

To combine information from heterogeneous sources, equivalent data in the multiple sources must be identified. This task is the field matching problem. Specifically, the task is to determine whether or not two syntactic values are alternative designations of the same semantic entity. For example the addresses Dept. of Comput. Sci. and Eng., University of California, San Diego, 9500 Gilman Dr. Dept. 0114, La Jolla. CA 92093 and UCSD, Computer Science and Engineering Department, CA 92093-0114 do designate the same department. This paper describes three field matching algorithms, and evaluates their performance on real-world datasets. One proposed method is the well-known Smith-Waterman algorithm for comparing DNA and protein sequences. Several applications of field matching in knowledge discovery are described briefly, including WEBFIND, which is a new software tool that discovers scientific papers published on the worldwide web. WEBFIND uses external information sources to guide its search for authors and papers. Like many other worldwide web tools, WEBFIND needs to solve the field matching problem in order to navigate between information sources.
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paper_title: WSMO-MX: A Logic Programming Based Hybrid Service Matchmaker

paper_content:

In this paper, we present an approach to hybrid semantic web service matching based on both logic programming, and syntactic similarity measurement. The implemented matchmaker, called WSMO-MX, applies different matching filters to retrieve WSMO-oriented service descriptions that are semantically relevant to a given query with respect to seven degrees of hybrid matching. These degrees are recursively computed by aggregated valuations of ontology based type matching, logical constraint and relation matching, and syntactic similarity as well.
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paper_title: Semantic Process Retrieval with iSPARQL

paper_content:

The vision of semantic business processes is to enable the integration and inter-operability of business processes across organizational boundaries. Since different organizations model their processes differently, the discovery and retrieval of similar semantic business processes is necessary in order to foster inter-organizational collaborations. This paper presents our approach of using iSPARQL --- our imprecise query engine based on iSPARQL --- to query the OWL MIT Process Handbook --- a large collection of over 5000 semantic business processes. We particularly show how easy it is to use iSPARQL to perform the presented process retrieval task. Furthermore, since choosing the best performing similarity strategy is a non-trivial, data-, and context-dependent task, we evaluate the performance of three simple and two human-engineered similarity strategies. In addition, we conduct machine learning experiments to learn similarity measures showing that complementary information contained in the different notions of similarity strategies provide a very high retrieval accuracy. Our preliminary results indicate that iSPARQL is indeed useful for extending the reach of queries and that it, therefore, is an enabler for inter- and intra-organizational collaborations.
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paper_title: Semantic Web Service Selection with SAWSDL-MX

paper_content:

In this paper, we present an approach to hybrid semantic Web service selection of semantic services in SAWSDL based on logic-based matching as well as text retrieval strategies. We discuss the principles of semantic Web service description in SAWSDL and selected problems for service matching implied by its specification. Based on the result of this discussion, we present different variants of hybrid semantic selection of SAWSDL services implemented by our matchmaker called SAWSDL-MX together with preliminary results of its performance in terms of recall/precision and average query response time. For experimental evaluation we created a first version of a SAWSDL service retrieval test collection called SAWSDL-TC.
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paper_title: Interleaving Execution and Planning for Nondeterministic, Partially Observable Domains

paper_content:

Methods that interleave planning and execution are a practical solution to deal with complex planning problems in non-deterministic domains under partial observability. However, most of the existing approaches do not tackle in a principled way the important issue of termination of the planning-execution loop, or only do so considering specific assumptions over the domains. ::: ::: In this paper, we tackle the problem of interleaving planning and execution relying on a general framework, which is able to deal with nondeterministic, partially observable planning domains. We propose a new, general planning algorithm that guarantees the termination of the interleaving of planning and execution: either the goal is achieved, or the system detects that there is no longer a guarantee to progress toward it. ::: ::: Our experimental analysis shows that our algorithm can efficiently solve planning problems that cannot be tackled with a state of the art off-line planner for nondeterministic domains under partial observability, MBP. Moreover, we show that our algorithm can efficiently detect situations where progress toward the goal can be no longer guaranteed.
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paper_title: Automatic location of services

paper_content:

The automatic location of services that fulfill a given need is a key step towards dynamic and scalable integration. In this paper we present a model for the automatic location of services that considers the static and dynamic aspects of service descriptions and identifies what notions and techniques are useful for the matching of both. Our model presents three important features: ease of use for the requester, efficient pre-filtering of relevant services, and accurate contracting of services that fulfill a given requester goal. We further elaborate previous work and results on Web service discovery by analyzing what steps and what kinds of descriptions are necessary for efficient and usable automatic service location. Furthermore, we analyze intuitive and formal notions of match that are of interest for locating services that fulfill a given goal. Although having a formal underpinning, the proposed model does not impose any restrictions on how to implement it for specific applications, but proposes some useful formalisms for providing such implementations.
---
paper_title: CASCOM: Intelligent Service Coordination in the Semantic Web

paper_content:

This book presents the design, implementation and validation of a value-added supportive infrastructure for Semantic Web based business application services across mobile and fixed networks, applied to an emergency healthcare application. This infrastructure has been realized by the CASCOM European research project. For end users, the CASCOM framework provides seamless access to semantic Web services anytime, anywhere, by using any mobile computing device. For service providers, CASCOM offers an innovative development platform for intelligent and mobile business application services in the Semantic Web. The essential approach of CASCOM is the innovative inter-disciplinary combination of intelligent agent, Semantic Web, peer-to-peer, and mobile computing technology. Conventional peer-to-peer computing environments are extended with components for mobile and wireless communication. Semantic Web services are provided by peer software agents, which exploit the coordination infrastructure to efficiently operate in highly dynamic environments. The generic coordination support infrastructure includes efficient communication means, support for context-aware adaptation techniques, as well as flexible, resource-efficient service discovery, execution, and composition planning. The book has three main parts. First, the state-or-the-art is reviewed in related research fields. Then, a full proof-of-concept design and implementation of the generic infrastructure is presented. Finally, quantitative and qualitative analysis is presented on the basis of the field trials of the emergency application.
---
paper_title: Semantic-Driven Matchmaking of Web Services Using Case-Based Reasoning

paper_content:

With the rapid proliferation of Web services as the medium of choice to securely publish application services beyond the firewall, the importance of accurate, yet flexible matchmaking of similar services gains importance both for the human user and for dynamic composition engines . In this paper, we present a novel approach that utilizes the case based reasoning methodology for modelling dynamic Web service discovery and matchmaking. Our framework considers Web services execution experiences in the decision making process and is highly adaptable to the service requester constraints. The framework also utilises OWL semantic descriptions extensively for implementing both the components of the CBR engine and the matchmaking profile of the Web services.
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paper_title: Review of Web services description approaches

paper_content:

The WS (Web services) description is an important step in the services consumption's cycle. Semantic WS extends the capabilities of a WS by associating semantic concepts in order to enable better search, discovery, selection, composition and integration. Several WS description approaches have been proposed to present a detailed description exceeding the limitations of the syntactic standard WSDL. Our analysis of these works leads us to group them into two classes: Annotations Based Description Approaches and Semantic Language Based Approaches. In this paper, we provide a comparative evaluation of these approaches based on a set of criteria that can be qualified as performance indicators. The identified comparison criteria are the following: ontology dependence, service description adaptation, expressiveness and the capacity of the description.
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paper_title: Semantic-Driven Matchmaking of Web Services Using Case-Based Reasoning

paper_content:

With the rapid proliferation of Web services as the medium of choice to securely publish application services beyond the firewall, the importance of accurate, yet flexible matchmaking of similar services gains importance both for the human user and for dynamic composition engines . In this paper, we present a novel approach that utilizes the case based reasoning methodology for modelling dynamic Web service discovery and matchmaking. Our framework considers Web services execution experiences in the decision making process and is highly adaptable to the service requester constraints. The framework also utilises OWL semantic descriptions extensively for implementing both the components of the CBR engine and the matchmaking profile of the Web services.
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Title: Semantic Web Service Discovery Approaches: Overview and Limitations

Section 1: Introduction
Description 1: This section provides an introduction to Web services, their importance in web engineering, and the motivation for Web service discovery. It also outlines the structure of the paper.

Section 2: Background and Motivation
Description 2: This section discusses the fundamental concepts of Web service discovery, its challenges, and the motivation behind developing new discovery approaches.

Section 3: Survey and Classification
Description 3: This section presents a detailed classification of existing Web service discovery approaches into algebraic, deductive, and hybrid categories, and describes some representative works for each category.

Section 4: Comparative Study of WS Discovery Approaches
Description 4: This section provides a comparative evaluation of the different Web service discovery approaches based on various criteria such as matching type, matching objects, and alignment with standards.

Section 5: Reuse of Experience and CBR-based Approaches for WS Discovery
Description 5: This section explores the concept of reuse of experience, specifically focusing on Case-Based Reasoning (CBR) approaches for improving Web service discovery.

Section 6: Comparative Study of CBR-based WS Discovery Approaches
Description 6: This section presents a comparative analysis of CBR-based Web service discovery approaches, evaluating their characteristics based on specific criteria relevant to CBR.

Section 7: Synthesis and Conclusion
Description 7: This section provides a synthesis of the survey and comparative studies, summarizing the advantages and limitations of existing approaches, and concluding with recommendations for future research.