bluuebunny/crossref_metadata_2025 huggingface dataset:
Management of Lecture Time
Authors: Chilton Michael A. , Gurung Anil
Published: February 2011

The variety of new technologies available for classroom use requires a choice not just between the technological options, but among them as well, since an educator may choose a single option or include a mix of media. In this study we investigate a particular mix of advanced technology and its effect on student learning outcomes. Our experimental design compares outcomes from a traditional teaching format with those of a more advanced web-based format. Our model is based on cognitive load theory, is developed from perceptions of the students, and is analyzed using factor analysis. The results based on this qualitative model show promise for delving further into the assessment of learning. This would provide researchers with additional tools to help evaluate their results and educators with a basis on which to make decisions regarding which advanced technologies to use.
Profiling Group Activity of Online Academic Workspaces
Authors: Karaiskakis D. , Kalles D. , Hadzilacos Th.
Published: February 2011

All undergraduate and postgraduate students of the Hellenic Open University (HOU) attend courses at a distance. The lack of a live academic community is reported by many as a drawback in their studies. Systematic exploitation of new communication and collaboration technologies is desirable in HOU but cannot be imposed universally as the average student’s IT competence level is relatively low. In this work, we present a key aspect of the development of an integrated communication environment in which collaboration spaces serving as open communities play a key role in user engagement in the whole communication environment. To track and evaluate user participation, we propose to use indices drawn from inexpensively collected usage data. Such indices, when combined with our detailed knowledge of the internal workings of user groups, provide concrete evaluation of the community online activity.
Teaching Dimension in Web-Based Learning Communities
Authors: Pozzi Francesca
Published: February 2011

The article tackles the issue of the teaching dimension in computer-supported collaborative learning (CSCL) contexts. In particular, it describes two Web-based courses that were held in 2006—one by the Istituto Tecnologie Didattiche – CNR and one by the University of Genoa, which, while sharing the socioconstructivist theoretical framework, adopt different approaches as far as the teaching dimension is concerned: While in the former course tutors were asked to cover all the functions typically required by e-tutors, in the latter, experience functions were distributed across a variety of actors. The aim of the work is to foster reflections about strong points and weaknesses of the two approaches, thus leading to considerations concerning the applicability of the models even in contexts different from the original ones.
Animated Pedagogical Agents
Authors: Heller R. , Procter M.
Published: February 2011

The role of Animated Pedagogical Agents (APAs) depends on an understanding of the persona effect as a mechanism for increasing student engagement and motivation. We argue that historical figure applications of APAs may be helpful to identify the parameters that give rise to a persona effect. Given the importance of visual information, an experimental approach was used to examine how different image conditions would affect perception of a historical figure APA interaction. Eighty-eight participants were randomly assigned to one of three conditions; no image, static image, or animated image. Contrary to expectations, the no image condition was associated with significantly higher ratings for 6 of the 12 measures, including 3 measures of social presence. These findings stand in contrast to previous research and suggest that historical figure applications may be unique in their evocation of a persona effect and valuable for understanding the nature of the persona effect.
Learning With Online Activities
Authors: Abdallah Salam
Published: February 2011

Learning through social interactions and critical thinking is becoming a fundamental teaching approach, especially for adult students. This approach promotes holistic and deeper understanding for the subject being learned. Online technologies are offering us new opportunities to create communities of inquiry that allow for more active learning that enhances students’ critical thinking. This article introduces an exploratory case in a Middle Eastern context that uses multiple online activities to supplement and strengthen the students’ face-to-face learning environment. This interpretive case discusses the students’ perceptions of their experience when using online activities. The case indicates that students improved their learning, are very positive about their first interaction with online activities and would like to see it as a standard practice to supplement their face-to-face learning.
An Evaluation of Blending Technology with Pedagogy for Teacher Education and its Implication for their Classroom Teaching
Authors: Kennedy Carol Kahan , Hinkley Maureen
Published: February 2011

Although research has been conducted on the benefits and drawbacks of online courses, more is specifically needed in teacher-education to increase understanding of the transfer process from technology integration learning to the classroom. This study was designed to evaluate a model for blending technology with traditional classroom methods in preparing teachers to do the same. A combination of qualitative and quantitative methods was used to examine the collaborative and scaffolding approaches to the teacher learners construction of meaning in the online discourse. Data has been collected from blended graduate level courses taught in the area of educational technology for in-service and pre-service teachers from 2001 through 2006. These findings will be used to help identify best-practices for technology integration with teacher-education through informed applied research, and to create a new model for more comprehensive future blended course design.
Every Need to be Alarmed
Authors: Young Ed
Published: February 2011

Demand for contemporary IT systems to support chronic availability, expansive integration and extensibility has never been greater.  Distributed infrastructures and particularly, the advent of Service Oriented Architecture (SOA) introduce new challenges for meeting these demands.  Despite architectural conventions to prescribe a common structure and simplifed approach, these systems are becoming more complex, heterogeneous and critical.  Comprehensive System Management is no longer a luxury.  Faults and potential failures have to be identified, isolated and addressed, and ideally pre-emptively.  Our front-line indicators are alarms.
Conceptual Business Service
Authors: Clohesy Ben , Frye Alan , Redpath Robert
Published: February 2011

Service Oriented Architecture (SOA) is gaining acceptance, offering advantages including closer alignment of IT systems with business. Ideally, within large enterprises, capabilities would be used by solutions from a number of business units while matching the detailed requirements of each; this level of interoperability is difficult to achieve. While much of the current activity focuses on technical interoperability we propose that the focus shift to business interoperability as the key consideration to bring clarity to the engineering aspects of technical interoperability. A model-driven architectural approach is presented that views an organization’s business processes as structured assets requiring formalization. A new concept is presented, the conceptual business service (CBS), which provides abstraction through modeling, and promotes building a portfolio of navigable business services at the appropriate level of abstraction and granularity. A method for specifying a CBS is outlined using reference domain meta-data allowing easier service solution recognition among other benefits.
Impact of Web Portal Announcements on Market Valuations
Authors: Gupta Manish , Sharman Raj
Published: February 2011

Organizations providing enhanced electronic services to their customers have exponentially increased in past years. The benefits of web-portals to companies and to customers are well evident and are considered an IT artifact manifested in entry points to Internet-based information presentation and exchange by communities of common interest. Despite much research done on the benefits of web portals to companies, no research exists that focuses on impact of adoption of web-portals on a company’s market valuation. In this paper, the authors look into impact of web-portal announcements on company’s stock prices (market value). Using event-study methodology, they provide empirical evidence on the effect of announcements of web portals on the market valuation of the company for a sample of 25 publicly traded companies in 2008. The study examines stock data to access investors and shareholders’ reactions to web portal announcements. Results indicate that web portal announcements significantly and positively influence investors’ perceptions toward financial worth and future prospects of the company. The authors discuss these findings in detail and present implications for both research and practice. Findings offer insight that can be used by managers and executives in understanding the role and effect of a companies’ market value.
A Spanning Tree Based Approach to Identifying Web Services
Authors: Jain Hemant , Zhao Huimin , Chinta Nageswara R.
Published: February 2011

Web service has been envisioned as an important trend in application development and integration. It allows pre-built applications/application components wrapped as web services to interact with each other through standardized interfaces and form larger application systems. This paper describes a formal approach to web services identification, which is a critical step in designing and developing effective web services. The approach takes an analysis level object model, representing a business domain, as input and generates potential web service designs, in which the classes in the object model are grouped into appropriate web services based on static and dynamic relationships between classes. An initial hierarchical grouping of classes is derived using a maximum spanning tree algorithm. A set of managerial goals for evaluating alternative designs is derived based on business strategy of web service fabricator. Since the managerial goals are conflicting, a multi-objective genetic algorithm has been designed to search for alternative non-dominated solutions, from which a preferred solution can be selected. The approach has been implemented in a web services identification tool and used for designing web services in an auto insurance claims domain. The experts evaluated the utility of the approach.
Web Services Enabled E-Market Access Control Model
Authors: Wang Harry J. , Cheng Hsing K. , Zhao J. Leon
Published: February 2011

With the dramtic expansion of global e-markets, companies collaborate more and more in order to streamline their supply chains. Companies often form coalitions to reach the critical mass required to bid on a large volume or wide ranges of products. Meanwhile, they also compete with one another for market shares. Because of the complex relationships among companies, controlling the access to shared information found in e-markets is a challenging task. Currently, there is a lack of comprehensive approach in access control that can be used to maintain data security in e-markets. We propose to integrate several known access control mechanisms such as role-based access control, coalition-based access control, and relationship driven access control into an e-market access control (EMAC) model. In this paper, we present a web services based architecture for EMAC and the associated concepts and algorithms. We also illustrate via an automotive e-market example how the EMAC model can support e-market access control.
Web Service Business Context
Authors: Marjanovic Olivera
Published: February 2011

This paper investigates the normative perspective of the Web service business context. The business context includes modeling of the business entities and their relationships, while its normative perspective deals with responsibilities, rights and obligations of both Web service providers and users. The existing literature and practice confirm the gap between the available Web service infrastructure and current understanding of the Web service business context - especially its normative perspective. The paper uses the Web service solution lifecycle to investigate formal modeling of terms and conditions, creation of the normative context for individual Web services as well as composition of Web services and creation and management of the resulting combined normative context. The main objective of this research is to facilitate better understanding of this phenomenon and ultimately initiate development of the new tools for management of the normative aspect both by the service providers and their customers.
Adaptation Space
Authors: Paques Henrique , Liu Ling , Pu Calton
Published: February 2011

Web service adaptation is an important feature for mission critical Web services. It is widely recognized that thrashing and crashes occur in system saturation for many statically adaptive resource management algorithms, including CPU, memory, and network congestion. Service adaptation supports alternative responses to saturation control, maintaining service and server system stability and progress, instead of thrashing. In this article, we present a design framework for developing adaptive Web services. The core of this framework is the adaptation space model, which is based on the concepts of adaptation space and adaptation case. An adaptation space is defined by a reference context and a partial order of adaptation cases. Each adaptation case describes a specific adaptation of a program or component of a Web service. We evaluate the adaptation space approach using Ginga, an adaptive query processing service for handling queries over multiple data sources with diverse capabilities across the Internet. Our experimental results show that Ginga query adaptation can achieve significant performance improvements (up to 40% of response time gain) for processing distributed queries over the Internet in the presence of end-to-end delays.
Pattern-Based Design of an Asynchronous Invocation Framework for Web Services
Authors: Zdun Uwe , Voelter Markus , Kircher Michael
Published: February 2011

Asynchronous invocations are needed in the context of distributed object frameworks to prevent clients from blocking during remote invocations. Popular Web service frameworks offer only synchronous invocations (over HTTP). An alternative is messaging protocols but these implement a different communication paradigm. When client asynchrony is not supported, client developers have to build asynchronous invocations on top of the synchronous invocation facility. But this is tedious, error-prone, and might result in different remote invocation styles used within the same application. We present a number of patterns for asynchronous invocations and explain how these patterns can be used to build asynchronous invocation facilities for Web service frameworks. We exemplify this approach by explaining the design and implementation of an asynchronous invocation framework for Apache Axis.
Seamlessly Securing Web Services by a Signing Proxy
Authors: Jeckle Mario , Melzer Ingo
Published: February 2011

Web services offer a way for very different systems to collaborate independent of the programming language used or the involved operating systems. Their basis is the XML-based SOAP protocol, which can be used over any protocol that is able to transport a byte stream. Due to the fact that Web services do not depend on any operating system and there is no burden of a underlying paradigm, they are ideal for the integration of even completely inhomogeneous systems. However, SOAP does not (and does not have to) deal with security issues, which is nevertheless important for the involved systems. This article describes an add-on for existing Internet proxies to achieve user and developer transparent security features for Web services. This approach allows corporate firewalls to handle authentication. A first step is to add corporate signatures to all outgoing SOAP messages to enable a corporate trust relationship. A second improvement is to use proxy authentication as defined in RFC 2616 and RFC 2617 to add personal signatures assuming that the proxy has access to some key management system.
Model-Driven Web Service Development
Authors: Gronmo Roy , Skogan David , Solheim Ida , Oldevik Jon
Published: February 2011

Web service technologies are becoming increasingly important for integrating systems and services. There is much activity and interest around standardization and usage of Web service technologies. Contemporary Web services are described in the Web Service Description Language (WSDL). However, WSDL documents can be difficult to understand for service developers. This article recommends a model-driven process for Web service development combining the graphical modeling language UML with WSDL. The Unified Modeling Language (UML) is developed by Object Management Group. In the proposed process, Web service descriptions (in WDSL) are converted to UML; their UML models are integrated to form composite Web services; and then the new Web service descriptions are exported. The main contribution of this article is a “pure UML” modeling strategy supported by implementation of two-way conversion rules between the UML models and the WSDL documents.
Dynamic Workflow Composition
Authors: Doshi Prashant , Goodwin Richard , Akkiraju Rama , Verma Kunal
Published: February 2011

The advent of Web services has made automated workflow composition relevant to Web-based applications. One technique that has received some attention for automatically composing workflows is AI-based classical planning. However, workflows generated by classical planning algorithms suffer from the paradoxical assumption of deterministic behavior of Web services, then requiring the additional overhead of execution monitoring to recover from unexpected behavior of services due to service failures, and the dynamic nature of real-world environments. To address these concerns, we propose using Markov decision processes (MDPs) to model workflow composition. To account for the uncertainty over the true environmental model, and for dynamic environments, we interleave MDP-based workflow generation and Bayesian model learning. Consequently, our method models both the inherent stochastic nature of Web services and the dynamic nature of the environment. Our algorithm produces workflows that are robust to non-deterministic behaviors of Web services and that adapt to a changing environment. We use a supply chain scenario to demonstrate our method and provide empirical results.
WSDL-Driven SOAP Compression
Authors: Werner Christian , Buschmann Carsten , Fischer Stefan
Published: February 2011

A major drawback of using SOAP for application integration is its enormous demand for network bandwidth. Compared to classical approaches like Java­RMI and Corba, SOAP messages typically cause more than three times more network traffic. In this paper we will explore compression strategies and give a detailed survey and evaluation of state-of-the-art binary encoding techniques for SOAP. We also introduce a new experimental concept for SOAP compression based on differential encoding, which makes use of the commonly available WSDL description of a SOAP Web service. We do not only conduct a detailed evaluation of compression effectiveness but also provide the results of execution time measurements.
A Service-Oriented Multimedia Componentization Model
Authors: Zhang Jia , Zhang Liang-Jie , Quek Francis , Chung Jen-Yao
Published: February 2011

As Web services become more and more popular, how to manage multimedia Web services that can be composed as value-added service solutions remains challenging. This paper presents a service-oriented multimedia componentization model to support Quality of Service (QoS)-centered, device-independent multimedia Web services, which seamlessly incorporates cutting-edge technologies relating to Web services. A multimedia Web service is divided into control flow and data flow. Each can be delivered via different infrastructures and channels. Enhancements are proposed to facilitate Simple Object Access Protocol (SOAP) and Composite Capability/Preference Profiles (CC/PP) protocols to improve their flexibility to serve multimedia Web services. We present a set of experiments that show the viability of our service-oriented componentization model that can support efficient delivery and management of multimedia Web services.
Discovery of Web Services in a Multi-Ontology and Federated Registry Environment
Authors: Oundhakar Swapna , Verman Kunal , Sivashanmugam Kaarthik , Sheth Amit , Miller John
Published: February 2011

The potential of a large-scale growth of private and semi-private registries is creating the need for an infrastructure that can support discovery and publication over a group of autonomous registries. Recent versions of UDDI have made changes to accommodate interactions between distributed registries. In this paper, we discuss an ontology-based Web service discovery infrastructure (METEOR-S Web Service Discovery Infrastructure), to provide access to registries that are divided based on business domains and grouped into federations. In addition, we discuss how Web service discovery is carried out within a federation. We provide a novel discovery algorithm, which addresses semantic heterogeneity with respect to multiple ontologies from the same domain. We also show through preliminary results of our empirical evaluation that even when services are annotated with different ontologies, our algorithm is able to find good matches and eliminate false matches by considering the context and the coverage information of the annotated concepts.
A Web-Services-Based Personal Information Integration Framework
Authors: Helal Sumi , Lu Jingting , Jansen Erwin
Published: February 2011

Managing fast-growing personal Web information is a time-consuming, laborious task that affects people’s daily lives. A framework is highly desired that will allow people to collect and fuse personal information without dealing with complex emerging technologies. In this paper, we present our E-Service-Based Information Fusion Framework for end users. This framework enables end users to collect scattered information from diverse autonomous sources and to transparently create a repeatable process by which newer instances of the same information can be obtained in the future. By exploiting this framework, users do not need to repeat the manual information-gathering task over and over again. We present our framework and provide some implementation details.
AND/OR Graph and Search Algorithm for Discovering Composite Web Services
Authors: Liang Qianhui Althea , Su Stanley Y.W.
Published: February 2011

This paper presents a formalization of the Web Service composition problem as a search problem in an AND/OR graph, and a search algorithm for searching the graph to identify composite service(s) that satisfies a Web Service request. Given a service request that can only be satisfied by a composition of Web Services, we identify the service categories that are relevant to the request and dynamically construct an AND/OR graph to capture the input/output dependencies among the Web Services of these service categories. The graph is modified, based on the information provided in the service request. The search algorithm is then used to search the modified AND/OR graph for a minimal and complete composite service template that satisfies the service request. The algorithm can be applied repeatedly to the graph to search for alternative templates until the result is approved by the service requester. We have evaluated the algorithm both analytically and experimentally, and the experiment results are presented.
Service-Oriented Solution Framework for Internet Banking
Authors: Shan Tony Chao , Hua Winnie Wei
Published: February 2011

This paper describes a service-oriented solution framework designed for Internet banking in financial services. A pragmatic approach is developed to help migrate conventional n-tier e-commerce systems to a service-oriented computing paradigm, composed of Service-Oriented Architecture (SOA), Integration (SOI), Process (SOP), and Management (SOM). This comprehensive framework comprises Service Patterns, Architecture Process, Hybrid Methodology, Service-Oriented Enterprise Model, and Solution Platform. E-business patterns are applied to categorize diverse online services, which form the baseline for subsequent selection justifications of appropriate technologies, products/tools, and infrastructure. A multi-level architecture process is developed to cope with the architecture complexity in a disciplined way. Furthermore, a hybrid methodology is designed to leverage the benefits of both top-down and bottom-up approaches, in which a converging layer is conceived to incorporate the latest technologies such as portal, process orchestration, Web services, service aggregations, business rule engine, and so forth. In the enterprise model, common business functionalities are built as shared services to be reused across lines of business as well as delivery channels, and the Internet channel-specific SOA is defined by applying the hybrid methodology. Finally, a holistic solution platform is introduced to address the key design artifacts in the implementation of service-oriented solutions. Challenges of conflicting specifications and immature cutting-edge technologies are also discussed in the context.
An Ontology-Based Content Model for Intelligent Web Content Access Services
Authors: Yang Steven J. , Shao Norman W.
Published: February 2011

Intelligent Web content access is a fundamental Web service, representing the first step toward semantic Web services. A lack of adequate and sufficient interpretation for content in current methods impedes access to content. This study regards Web content as any content described and published in the format of a markup language such as HTML or XML. In this paper, we will present our Content Model, combining subjective information from the content itself with objective information from people’s perceptions of this content, providing an integrated interpretation of a content item. During accessing, a search engine examines the description of a content item, as found in the Content Model, to find matching files. An ontology-based Content Model is developed and applied to the Web environment to enhance Web content accessibility. Results of this study demonstrate that the proposed Content Model provides essential content descriptions for locating, accessing, and interacting with content providers.
Self-Reconfiguration of Service-Based System for Service Level Agreements and Resource Optimization
Authors: Li Ying , Sun Kewei , Qiu Jie , Chen Ying
Published: February 2011

The configuration of a service-based system has a significant impact on the non-functional requirements of the system as a whole. However, finding the best configuration is very challenging and sometimes impossible for administrators because so many factors have to be considered. More importantly, a service-based system has to be frequently reconfigured to adapt to rapid and continuous changes in user requirements and runtime environments. In this paper we propose an autonomic computing approach to the problem of reconfiguration, that is, enabling the service-based system to configure itself by means of a loop of monitoring, analyzing, planning and executing. We begin by formalizing the definition of reconfiguration. Then, we describe how to implement the autonomic computing mechanisms for reconfiguring service-based systems to satisfy Service Level Agreements with minimal resource consumption. The approach is demonstrated on a resilient service provisioning environment. Finally, the preliminary experiments are evaluated to determine the effectiveness of proposed approach.
UML-Based Support for Designing and Validating Web Service Descriptions
Authors: Jiang Juanjuan. , Systa Tarja
Published: February 2011

WSDL descriptions, often characterized as IDLs for Web services, are a key for Web service interoperability. Therefore, special care should be taken in designing WSDL descriptions. We present an approach that provides UML-based support to design and validate WSDL descriptions. To promote Web service interoperability, WS-I organization provides a Basic Profile that defines clarifications, refinements, interpretations, and amplifications of Web service specifications, including WSDL. We propose UML-based profiles to define structural rules of WSDL documents as well as Basic Profile recommendations for WSDL descriptions. These profiles can be used to guide the user in designing correct and Basic-Profile-compliant WSDL descriptions and to check the validity of existing WSDL descriptions. We propose a method and tools for such validity checking, and demonstrate the applicability of the approach with case studies.
Using Concept Lattices to Support Service Selection
Authors: Aversano Lerina , Bruno Marcello , Canfora Gerardo , Di Penta Massimiliano , Distante Damiano
Published: February 2011

When building a service-oriented system, a service integrator retrieves a set of potentially useful services from registries and then inspects their documentation to eventually decide which services to use. This task needs to be supported by proper tools that help service interface/documentation understanding, highlighting the relationships existing between the retrieved services. This paper proposes an approach, based on Formal Concept Analysis, to understand relationships between services, as well as between operations of a complex service, by analyzing service interfaces and documentation. The approach allows an analyst to cluster similar services, highlights hierarchical relationships and, in general, commonalities and differences between services. To support the proposed approach, we developed a tool that provides several service browsing capabilities. Finally, the approach has been evaluated with different case studies built upon real sets of services.
Web Service Planner (WSPR)
Authors: Oh Seog-Chan , Lee Dongwon , Kumara Soundar R.T.
Published: February 2011

As the emergence of service-oriented architecture provides a major boost for e-commerce agility, the number of available Web services is rapidly increasing. However, when there are a large number of Web services available and no single Web service satisfies the given request, one has to “compose” multiple Web services to fulfill the goal. In this article, toward this problem, we present an AI planning-based Web service composition algorithm named as WSPR. We evaluate the efficiency and effectiveness of WSPR using two publicly available test sets—EEE05 and ICEBE05. In addition, we analyze the two test sets and suggest several improvements to benchmark Web service composition better.
BITS
Authors: Zhou Aoying , Huang Sheng , Wang Xiaoling
Published: February 2011

In current service-oriented applications, each individual Web service usually cannot satisfy users’ requests for Web services, but the functionalities of different Web services may be integrated to accomplish requested task. This process is called Web service composition, and the resulted service is called composite Web service. The discovery and composition of Web services are two important research issues. In this article, a Web service composition system, BITS, which won the championship of the ICEBE05 contest due to its outstanding performance, is introduced. BITS is implemented based on a binary tree which is used to organize Web services. In this system, some search strategies and optimization techniques are developed for efficient service discovery and service composition. Extensive experiments are conducted for performance study, and the results show the efficiency and effectiveness of the methods adopted in BITS.
Service Portfolio Measurement
Authors: Vom Brocke Jan
Published: February 2011

Service-oriented architectures offer promising means to flexibly organize business processes. At the same time, new challenges for management arise in order to realize these potentials. Given the technological opportunities, these challenges essentially lie in choosing the right mix of services on the basis of an appropriate infrastructure supporting value adding activities. In order to support this management perspective, a focus on service-oriented business processes is suggested in this article. Hence, a shift from technical aspects of designing service-oriented information systems to economic aspects of using them according to business needs is drawn. For this purpose, findings on the evaluation of financial performance of service-oriented business processes are presented in this paper. The objective is to develop a measurement system for decision support on the con-figuration of a company’s service portfolio reflecting specific economic conditions relevant in a certain situation. Following a design science approach, general principles of a measurement system are worked out and structured in a comprehensive framework. Then, the application of a corresponding system is presented with a practical study. Finally, perspectives on the specification and implementation of the system are sketched.
Architecture-Driven Service Discovery for Service Centric Systems
Authors: Kozlenkov A. , Spanoudakis G. , Zisman A. , Fasoulas V. , Sanchez F.
Published: February 2011

Service discovery has been recognized as an important aspect in the development of service-centric systems, i.e., software systems which deploy Web services. To develop such systems, it is necessary to identify services that can be combined in order to fulfill the functionality and achieve quality criteria of the system being developed. In this paper, we present a framework supporting architecture-driven service discovery (ASD)—that is the discovery of services that can provide functionalities and satisfy properties and constraints of systems as specified during the design phase of the development lifecycle based on detailed system design models. Our framework assumes an iterative design process and allows for the (re-)formulation of design models of service-centric systems based on the discovered services. The framework is composed of a query extractor, which derives queries from behavioral and structural UML design models of service-centric systems, and a query execution engine that executes these queries against service registries based on graph matching techniques. The article describes a prototype tool that we have developed to demonstrate and evaluate our framework and the results of a set of preliminary experiments that we have conducted to evaluate it.
Service Class Driven Dynamic Data Source Discovery with DynaBot
Authors: Rocco Daniel , Caverlee James , Liu Ling , Critchlow Terence
Published: February 2011

Dynamic Web data sources on the Deep Web provide intuitive access to real-time information and large data repositories anywhere that Web access is available. Although recent studies suggest that the dynamic Web is larger and growing faster than static Web, dynamic content is often ignored by existing search engine indexers owing to technical challenges inherent in searching dynamic sources. To address these challenges, we present DynaBot, a service-centric crawler for discovering and clustering Deep Web sources. Dyna- Bot has three unique characteristics. First, DynaBot utilizes a service class model implemented through the construction of service class descriptions (SCDs). Second, DynaBot employs a modular architecture for focused crawling of the Deep Web. Third, DynaBot incorporates algorithms for efficiently probing, discovering, and clustering Deep Web sources through SCD-based service analysis. Experimental results demonstrate DynaBot’s effectiveness and suggest techniques for efficiently managing service discovery given the immense scale of the Deep Web.
Web Service versus Distributed Objects
Authors: Cook William R. , Barfield Janel
Published: February 2011

Web services are promoted as a new model for distributed systems, yet many skeptics see them as simply a poor implementation of traditional remote procedure calls (RPC) or distributed objects. Previous comparisons, which show Web services to be significantly slower than RPC, are biased because they use a RPC communication style and ignore the document-oriented style that is recommended for Web services. We compare the straightforward design and implementation of a small file server application implemented using proxy-based RMI and document-oriented Web services. We show that Web services outperform RMI when accessing multiple/deeply nested files, especially over high-latency networks. However, the automatically generated Web service interfaces are awkward to use, so we develop a technique for wrapping the Web service to make it as easy to use as the distributed object implementation. This case study provides a more detailed comparison of the relationship between Web services and distributed objects.
Fully Automated Web Services Discovery and Composition Through Concept Covering and Concept Abduction
Authors: Ragone Azzurra , Di Noia Tommaso , Di Sciascio Eugenio , Donini Francesco M. , Colucci Simona , Colasuonno Francesco
Published: February 2011

We propose a framework and tractable algorithms for semantic-based automated Web service composition, fully compliant with Semantic Web technologies. The approach exploits the recently proposed Concept Abduction inference service in Description Logics to extend Concept covering definition to expressive logics, and to solve Concept Covering problems in a significant subset of OWL-DL. We show how the proposed approach also deals with not-exact solutions, computing an approximate composition and providing an explanation of which part of the request is not covered by the composite service. We present the formalization of the approach, the proposed algorithms, a prototype system implementing the approach, and illustrate experiments carried out with it.
Development of Distance Measures for Process Mining, Discovery and Integration
Authors: Bae Joonsoo , Liu Ling , Caverlee James , Zhang Liang-Jie , Bae Hyerim
Published: February 2011

Business processes continue to play an important role in today’s service-oriented enterprise computing systems. Mining, discovering, and integrating process-oriented services has attracted growing attention in the recent years. In this article, we present a quantitative approach to modeling and capturing the similarity and dissimilarity between different process designs. We derive the similarity measures by analyzing the process dependency graphs of the participating workflow processes. We first convert each process dependency graph into a normalized process matrix. Then we calculate the metric space distance between the normalized matrices. This distance measure can be used as a quantitative and qualitative tool in process mining, process merging, and process clustering, and ultimately it can reduce or minimize the costs involved in design, analysis, and evolution of workflow systems.
Automated Situation-Aware Service Composition in Service-Oriented Computing
Authors: Yau S.S. , Davulcu H. , Mukhopadhyay S. , Huang D. , Gong H. , Singh P. , Gelgi F.
Published: February 2011

Service-based systems have many applications, such as e-business, health care, and homeland security. In these systems, it is necessary to provide users the capability of composing services into workflows providing higher-level functionality. In dynamic service-oriented computing environments, it is desirable that service composition is automated and situation-aware to generate robust and adaptive workflows. In this paper, an automated situation-aware service composition approach is presented. This approach is based on the a-logic, a-calculus, and a declarative model for situation awareness (SAW). This approach consists of four major components: (1) analyzing SAW requirements using our SAW model, (2) translating our SAW model representation to a-logic specifications and specifying a control flow graph in a-logic as the service composition goal, (3) automated synthesis of a-calculus terms defining situation-aware workflow agents based on a-logic specifications for SAW requirements and the control flow graph, and (4) compilation of a-calculus terms to executable components.
Security Personalization for Internet and Web Services
Authors: Yee George O.M. , Korba Larry
Published: February 2011

The growth of the Internet has been accompanied by the growth of Internet services (e.g., e-commerce, e-health). This proliferation of services and the increasing attacks on them by malicious individuals have highlighted the need for service security. The security requirements of an Internet or Web service may be specified in a security policy. The provider of the service is then responsible for implementing the security measures contained in the policy. However, a service customer or consumer may have security preferences that are not reflected in the provider’s security policy. In order for service providers to attract and retain customers, as well as reach a wider market, a way of personalizing a security policy to a particular customer is needed. We derive the content of an Internet or Web service security policy and propose a flexible security personalization approach that will allow an Internet or Web service provider and customer to negotiate to an agreed-upon personalized security policy. In addition, we present two application examples of security policy personalization, and overview the design of our security personalization prototype.
Automating the Composition of Transactional Web Services
Authors: Montagut Frederic , Molva Refik , Golega Silvan Tecumseh
Published: February 2011

Composite applications leveraging the functionalities offered by Web services today are the underpinnings of enterprise computing. However, current Web services composition systems make only use of functional requirements in the selection process of component Web services while transactional consistency is a crucial parameter of most business applications. The transactional challenges raised by the composition of Web services are twofold: integrating relaxed atomicity constraints at both design and composition time and coping with the dynamicity introduced by the service oriented computing paradigm. In this paper, we propose a new process to automate the design of transactional composite Web services. Our solution for Web services composition does not take into account functional requirements only but also transactional ones based on the acceptable termination states model. The resulting composite Web service is compliant with the consistency requirements expressed by business application designers and its execution can easily be coordinated using the coordination rules provided as an outcome of our approach. An implementation of our theoretical results augmenting an OWL-S matchmaker is further detailed as a proof of concept.
Data Mining in Web Services Discovery and Monitoring
Authors: Nayak Richi
Published: February 2011

The business needs, the availability of huge volumes of data and the continuous evolution in Web services functions derive the need of application of data mining in the Web service domain. This article recommends several data mining applications that can leverage problems concerned with the discovery and monitoring of Web services. This article then presents a case study on applying the clustering data mining technique to the Web service usage data to improve the Web service discovery process. This article also discusses the challenges that arise when applying data mining to Web services usage data and abstract informat
Mining and Improving Composite Web Services Recovery Mechanisms
Authors: Bhiri Sami , Gaaloul Walid , Godart Claude
Published: February 2011

Ensuring composite services reliability is a challenging problem. Indeed, due to the inherent autonomy and heterogeneity of Web services, it is difficult to predict and reason about the behavior of the overall composite service (CS). Generally, previous approaches develop, using their modeling formalisms, a set of techniques to analyze the composition model and check “correctness” properties. Although powerful, these approaches may fail in some cases in order to ensure CS-reliable executions, even if they formally validate its composition model. This is because properties specified in the studied composition model remain assumptions that may not coincide with the reality (i.e., effective CS executions). Sharing the same issue, we present a reengineering approach that starts from CS executions log to improve its recovery mechanisms. Basically, we propose a set of mining techniques to discover CS transactional behavior from an event-based log. Then, based on this mining step, we use a set of rules in order to improve its reliability.
DsCWeaver
Authors: Wu Qinyi , Pu Calton , Sahai Akhil , Barga Roger
Published: February 2011

Correct synchronization among activities is critical in a business process. Current process languages such as BPEL specify the control flow of processes procedurally, which can lead to inflexible and tangled code for managing a crosscutting aspect—synchronization constraints that define permissible sequences of execution for activities. In this article, we present DSCWeaver, a tool that enables a synchronization-aspect extension to procedural languages. It uses DSCL (directed-acyclic-graph synchronization constraint language) to achieve three desirable properties for synchronization modeling: fine granularity, declarative syntax, and validation support. DSCWeaver then automatically generates executable code for synchronization. We demonstrate the advantages of our approach in a service deployment process written in BPEL and evaluate its performance using two metrics: lines of code (LoC) and places to visit (PtV). Evaluation results show that our approach can effectively reduce the development effort of process programmers while providing performance competitive to unwoven BPEL code.
Workflow Discovery
Authors: Goderis Antoon , Li Peter , Goble Carole
Published: February 2011

Much has been written on the promise of Web service discovery and (semi-) automated composition. In this discussion, the value to practitioners of discovering and reusing existing service compositions, captured in workflows, is mostly ignored. We present the case for workflows and workflow discovery in science and develop one discovery solution. Through a survey with 21 scientists and developers from the myGrid/Taverna workflow environment, workflow discovery requirements are elicited. Through a user experiment with 13 scientists, an attempt is made to build a benchmark for workflow ranking. Through the design and implementation of a workflow discovery tool, a mechanism for ranking workflow fragments is provided based on graph sub-isomorphism detection. The tool evaluation, drawing on a corpus of 89 public workflows and the results of the user experiment, finds that, for a simple showcase, the average human ranking can largely be reproduced.