Showing papers on "Web modeling published in 2003"

Web Services: Concepts, Architectures and Applications

Abstract: Like many other incipient technologies, Web services are still surrounded by a substantial level of noise. This noise results from the always dangerous combination of wishful thinking on the part of research and industry and of a lack of clear understanding of how Web services came to be. On the one hand, multiple contradictory interpretations are created by the many attempts to realign existing technology and strategies with Web services. On the other hand, the emphasis on what could be done with Web services in the future often makes us lose track of what can be really done with Web services today and in the short term. These factors make it extremely difficult to get a coherent picture of what Web services are, what they contribute, and where they will be applied.Alonso and his co-authors deliberately take a step back. Based on their academic and industrial experience with middleware and enterprise application integration systems, they describe the fundamental concepts behind the notion of Web services and present them as the natural evolution of conventional middleware, necessary to meet the challenges of the Web and of B2B application integration. Rather than providing a reference guide or a "how to write your first Web service" kind of book, they discuss the main objectives of Web services, the challenges that must be faced to achieve them, and the opportunities that this novel technology provides. Established, as well as recently proposed, standards and techniques (e.g., WSDL, UDDI, SOAP, WS-Coordination, WS-Transactions, and BPEL), are then examined in the context of this discussion in order to emphasize their scope, benefits, and shortcomings. Thus, the book is ideally suited both for professionals considering the development of application integration solutions and for research and students interesting in understanding and contributing to the evolution of enterprise application technologies.

Web services orchestration and choreography

Abstract: Combining Web services to create higher level, cross-organizational business processes requires standards to model the interactions. Several standards are working their way through industry channels and into vendor products.

Quality driven web services composition

Abstract: The process-driven composition of Web services is emerging as a promising approach to integrate business applications within and across organizational boundaries. In this approach, individual Web services are federated into composite Web services whose business logic is expressed as a process model. The tasks of this process model are essentially invocations to functionalities offered by the underlying component services. Usually, several component services are able to execute a given task, although with different levels of pricing and quality. In this paper, we advocate that the selection of component services should be carried out during the execution of a composite service, rather than at design-time. In addition, this selection should consider multiple criteria (e.g., price, duration, reliability), and it should take into account global constraints and preferences set by the user (e.g., budget constraints). Accordingly, the paper proposes a global planning approach to optimally select component services during the execution of a composite service. Service selection is formulated as an optimization problem which can be solved using efficient linear programming methods. Experimental results show that this global planning approach outperforms approaches in which the component services are selected individually for each task in a composite service.

Web mining for web personalization

Abstract: Web personalization is the process of customizing a Web site to the needs of specific users, taking advantage of the knowledge acquired from the analysis of the user's navigational behavior (usage data) in correlation with other information collected in the Web context, namely, structure, content, and user profile data. Due to the explosive growth of the Web, the domain of Web personalization has gained great momentum both in the research and commercial areas. In this article we present a survey of the use of Web mining for Web personalization. More specifically, we introduce the modules that comprise a Web personalization system, emphasizing the Web usage mining module. A review of the most common methods that are used as well as technical issues that occur is given, along with a brief overview of the most popular tools and applications available from software vendors. Moreover, the most important research initiatives in the Web usage mining and personalization areas are presented.

A software framework for matchmaking based on semantic web technology

Abstract: An important objective of the Semantic Web is to make Electronic Commerce interactions more flexible and automated. To achieve this, standardization of ontologies, message content and message protocols will be necessary.In this paper we investigate how Semantic and Web Services technologies can be used to support service advertisement and discovery in e-commerce. In particular, we describe the design and implementation of a service matchmaking prototype which uses a DAML-S based ontology and a Description Logic reasoner to compare ontology based service descriptions. We also present the results of initial experiments testing the performance of this prototype implementation in a realistic agent based e-commerce scenario.

Semantic search

Abstract: Activities such as Web Services and the Semantic Web are working to create a web of distributed machine understandable data. In this paper we present an application called 'Semantic Search' which is built on these supporting technologies and is designed to improve traditional web searching. We provide an overview of TAP, the application framework upon which the Semantic Search is built. We describe two implemented Semantic Search systems which, based on the denotation of the search query, augment traditional search results with relevant data aggregated from distributed sources. We also discuss some general issues related to searching and the Semantic Web and outline how an understanding of the semantics of the search terms can be used to provide better results.

Structured methodology and design patterns for web services

Abstract: System and method for designing and implementing Web Services according to a structured methodology and design patterns. Embodiments may incorporate a structured methodology, best practices and design patterns that address reliability, availability and scalability of Web Services architecture. Embodiments may provide mechanisms for integrating heterogeneous technology components into Web Services. Embodiments may provide a vendor-independent Web Services architecture framework and reusable Web Services design patterns, which may be used in creating end-to-end solutions based on past experience and best practices. Embodiments may include design patterns and best practices for delivering Web Services solutions with Quality of Services. One embodiment may provide a Business-to-Business Integration (B2Bi) integration framework for Web Services. Embodiments may provide a Web Security framework and design patterns for designing end-to-end Web Services security.

A Petri net-based model for web service composition

Abstract: The Internet is going through several major changes. It has become a vehicle of Web services rather than just a repository of information. Many organizations are putting their core business competencies on the Internet as a collection of Web services. An important challenge is to integrate them to create new value-added Web services in ways that could never be foreseen forming what is known as Business-to-Business (B2B) services. Therefore, there is a need for modeling techniques and tools for reliable Web service composition. In this paper, we propose a Petri net-based algebra, used to model control flows, as a necessary constituent of reliable Web service composition process. This algebra is expressive enough to capture the semantics of complex Web service combinations.

Composing Web services on the Semantic Web

Abstract: Service composition is gaining momentum as the potential silver bullet for the envisioned Semantic Web. It purports to take the Web to unexplored efficiencies and provide a flexible approach for promoting all types of activities in tomorrow’s Web. Applications expected to heavily take advantage of Web service composition include B2B E-commerce and E-government. To date, enabling composite services has largely been an ad hoc, time-consuming, and error-prone process involving repetitive low-level programming. In this paper, we propose an ontology-based framework for the automatic composition of Web services. We present a technique to generate composite services from high-level declarative descriptions. We define formal safeguards for meaningful composition through the use of composability rules. These rules compare the syntactic and semantic features of Web services to determine whether two services are composable. We provide an implementation using an E-government application offering customized services to indigent citizens. Finally, we present an exhaustive performance experiment to assess the scalability of our approach.

Web Service Composition - Current Solutions and Open Problems

Abstract: Composition of Web services has received much interest to support business-to-business or enterprise application integration. On the one side, the business world has developed a number of XML-based standards to formalize the specification of Web services, their flow composition and execution. This approach is primarily syntactical: Web service interfaces are like remote procedure call and the interaction protocols are manually written. On the other side, the Semantic Web community focuses on reasoning about web resources by explicitly declaring their preconditions and effects with terms precisely defined in ontologies. For the composition of Web services, they draw on the goal-oriented inferencing from planning. So far, both approaches have been developed rather independently from each other. We compare these approaches and discuss their solutions to the problems of modeling, composing, executing, and verifying Web services. We discuss what makes the Web service composition so special and derive challenges for the AI planning community.

The Semantic Web: A Guide to the Future of XML, Web Services and Knowledge Management

Abstract: From the Publisher: "The Semantic Web is an extension of the current Web in which information is given well-defined meaning, better enabling computers and people to work in cooperation."–Tim Berners-Lee, Scientific American, May 2001 This authoritative guide shows how the Semantic Web works technically and how businesses can utilize it to gain a competitive advantage Explains what taxonomies and ontologies are as well as their importance in constructing the Semantic Web Companion Web site includes further updates as the framework develops and links to related sites

Automating DAML-S web services composition using SHOP2

Abstract: The DAML-S Process Model is designed to support the application of AI planning techniques to the automated composition of Web services. SHOP2 is an Hierarchical Task Network (HTN) planner well-suited for working with the Process Model. We have proven the correspondence between the semantics of SHOP2 and the situation calculus semantics of the Process Model. We have also implemented a system which soundly and completely plans over sets of DAML-S descriptions using a SHOP2 planner, and then executes the resulting plans over the Web. We discuss the challenges and difficulties of using SHOP2 in the information-rich and human-oriented context of Web services.

Adding Semantics to Web Services Standards

Abstract: With the increasing growth in popularity of Web services, discovery of relevant Web services becomes a significant challenge. One approach is to develop semantic Web services where by the Web services are annotated based on shared ontologies, and use these annotations for semantics-based discovery of relevant Web services. We discuss one such approach that involves adding semantics to WSDL using DAML+OIL ontologies. Our approach also uses UDDI to store these semantic annotations and search for Web services based on them. We compare our approach with another initiative to add semantics to support Web service discovery, and show how our approach may fit current standards-based industry approach better.

Semantic E-Workflow Composition

Abstract: Systems and infrastructures are currently being developed to support Web services. The main idea is to encapsulate an organization's functionality within an appropriate interface and advertise it as Web services. While in some cases Web services may be utilized in an isolated form, it is normal to expect Web services to be integrated as part of workflow processes. The composition of workflow processes that model e-service applications differs from the design of traditional workflows, in terms of the number of tasks (Web services) available to the composition process, in their heterogeneity, and in their autonomy. Therefore, two problems need to be solved: how to efficiently discover Web services—based on functional and operational requirements—and how to facilitate the interoperability of heterogeneous Web services. In this paper, we present a solution within the context of the emerging Semantic Web that includes use of ontologies to overcome some of the problem. We describe a prototype that has been implemented to illustrate how discovery and interoperability functions are achieved more efficiently.

Web Usage Mining as a Tool for Personalization: A Survey

Abstract: This paper is a survey of recent work in the field of web usage mining for the benefitof research on the personalization of Web-based information services. The essence of personalization is the adaptability of information systems to the needs of their users. This issue is becoming increasingly important on the Web, as non-expert users are overwhelmed by the quantity of information available online, while commercial Web sites strive to add value to their services in order to create loyal relationships with their visitors-customers. This article views Web personalization through the prism of personalization policies adopted by Web sites and implementing a variety of functions. In this context, the area of Web usage mining is a valuable source of ideas and methods for the implementation of personalization functionality. We therefore present a survey of the most recent work in the field of Web usage mining, focusing on the problemsthat have been identified and the solutions that have been proposed.

Web application security assessment by fault injection and behavior monitoring

Abstract: As a large and complex application platform, the World Wide Web is capable of delivering a broad range of sophisticated applications. However, many Web applications go through rapid development phases with extremely short turnaround time, making it difficult to eliminate vulnerabilities. Here we analyze the design of Web application security assessment mechanisms in order to identify poor coding practices that render Web applications vulnerable to attacks such as SQL injection and cross-site scripting. We describe the use of a number of software-testing techniques (including dynamic analysis, black-box testing, fault injection, and behavior monitoring), and suggest mechanisms for applying these techniques to Web applications. Real-world situations are used to test a tool we named the Web Application Vulnerability and Error Scanner (WAVES, an open-source project available at http://waves.sourceforge.net) and to compare it with other tools. Our results show that WAVES is a feasible platform for assessing Web application security.

Extracting content structure for web pages based on visual representation

Abstract: A new web content structure based on visual representation is proposed in this paper. Many web applications such as information retrieval, information extraction and automatic page adaptation can benefit from this structure. This paper presents an automatic top-down, tag-tree independent approach to detect web content structure. It simulates how a user understands web layout structure based on his visual perception. Comparing to other existing techniques, our approach is independent to underlying documentation representation such as HTML and works well even when the HTML structure is far different from layout structure. Experiments show satisfactory results.

Detecting web page structure for adaptive viewing on small form factor devices

Abstract: Mobile devices have already been widely used to access the Web. However, because most available web pages are designed for desktop PC in mind, it is inconvenient to browse these large web pages on a mobile device with a small screen. In this paper, we propose a new browsing convention to facilitate navigation and reading on a small-form-factor device. A web page is organized into a two level hierarchy with a thumbnail representation at the top level for providing a global view and index to a set of sub-pages at the bottom level for detail information. A page adaptation technique is also developed to analyze the structure of an existing web page and split it into small and logically related units that fit into the screen of a mobile device. For a web page not suitable for splitting, auto-positioning or scrolling-by-block is used to assist the browsing as an alterative. Our experimental results show that our proposed browsing convention and developed page adaptation scheme greatly improve the user's browsing experiences on a device with a small display.

A Framework for the Evaluation of Session Reconstruction Heuristics in Web-Usage Analysis

Abstract: Web-usage mining has become the subject of intensive research, as its potential for personalized services, adaptive Web sites and customer profiling is recognized. However, the reliability of Web-usage mining results depends heavily on the proper preparation of the input datasets. In particular, errors in the reconstruction of sessions and incomplete tracing of users' activities in a site can easily result in invalid patterns and wrong conclusions. In this study, we evaluate the performance of heuristics employed to reconstruct sessions from the server log data. Such heuristics are called to partition activities first by user and then by visit of the user in the site, where user identification mechanisms, such as cookies, may or may not be available. We propose a set of performance measures that are sensitive to two types of reconstruction errors and appropriate for different applications in knowledge discovery (KDD) applications.We have tested our framework on the Web server data of a frame-based Web site. The first experiment concerned a specific KDD application and has shown the sensitivity of the heuristics to particularities of the site's structure and traffic. The second experiment is not bound to a specific application but rather compares the performance of the heuristics for different measures and thus for different application types. Our results show that there is no single best heuristic, but our measures help the analyst in the selection of the heuristic best suited for the application at hand.

ABC of learning and teaching: Web based learning

Abstract: Many of us use the internet or the “web” (world wide web) as a source of information. In medical education, the web is increasingly used both as a learning tool to support formal programmes and as a means of delivering online learning programmes. What can educators do to ensure that the potential of the web is used effectively to support both their own learning and that of their students? Much of the literature on web based learning shows that one of the main barriers to the effective use of teaching materials is the technology (for example, poor access, slow downloading) rather than the design of the learning materials themselves. Some of these issues are discussed later in the article, but it is vital that teachers take on expert help with technical issues in the planning, design, and delivery of web based learning programmes. Through programming and the use of “plug-ins” (programs that can be downloaded from the internet), designers can produce interactive course materials containing online activities (such as self assessments), animations, and simulations. These can improve learning and are often more enjoyable and meaningful for learners. #### Glossary E-conferencing —Use of online presentations and discussion forums (in real time or stored as downloadable files on a website) to avoid the need for participants to travel E-learning —Learning through electronic means, such as via the web (see world wide web), an intranet, or other multimedia materials HTML (hypertext markup language) —The language used to create web pages. HTML files can also contain links to other types of files including wordprocessed files, spreadsheets, presentation slides, and other web pages Hyperlinks —Links in web pages that enable the user to access another web page (either on the same or a different site) with just one mouse click Internet— A global network of computers divided …

A policy based approach to security for the semantic web

Abstract: Along with developing specifications for the description of meta-data and the extraction of information for the Semantic Web, it is important to maximize security in this environment, which is fundamentally dynamic, open and devoid of many of the clues human societies have relied on for security assessment. Our research investigates the marking up of web entities with a semantic policy language and the use of distributed policy management as an alternative to traditional authentication and access control schemes. The policy language allows policies to be described in terms of deontic concepts and models speech acts, which allows the dynamic modification of existing policies, decentralized security control and less exhaustive policies. We present a security framework, based on this policy language, which addresses security issues for web resources, agents and services in the Semantic Web.

Bringing semantics to Web services

Abstract: A key element to realizing the Semantic Web is developing a suitably rich language for encoding and describing Web content. Such a language must have a well defined semantics, be sufficiently expressive to describe the complex interrelationships and constraints between Web objects, and be amenable to automated manipulation and reasoning with acceptable limits on time and resource requirements. A key component of the Semantic Web services vision is the creation of a language for describing Web services. DAML-S is such a language it is a DAML+OIL ontology for describing Web services that a coalition of researchers created with support from DARPA.

Understanding the Semantic Web through Descriptions and Situations

Abstract: The Semantic Web is a powerful vision that is getting to grips with the challenge of providing more human-oriented web services. Hence, reasoning with and across distributed, partially implicit assumptions (contextual knowledge), is a milestone.

Extensible user interface (xui) framework and development environment

Abstract: A web application development environment and method employs an extensible user interface (XUI) Framework for creating GUI-managing components written in a declarative format for handling GUI components in a web application. The GUI-managing components are coordinated in a view presentation layer by a Controller in an Extended-Model-View-Controller (XMVC) pattern in conjunction with the business logic layer. The Controller is invoked by a user request for a web page and in turn invokes the GUI-managing components to parse information contained in a corresponding web application file for the requested web page in order to determine the templates and sub-templates to be invoked for handling the GUI components. Each template has a mode value which is set by mode information contained in the web application file for the requested web page. The XUI Framework has the ability to handle a rich set of GUI components without having to implement web applications development technologies. Instead, the declarative-formatted GUI components can be created and processed using lightweight technologies for client-side and server-side processing. The XUI Framework allows for the efficient authoring and processing of GUI components for a wide range of web applications.

Adapting BPEL4WS for the semantic web: the bottom-up approach to web service interoperation

Abstract: Towards the ultimate goal of seamless interaction among networked programs and devices, industry has developed orchestration and process modeling languages such as XLANG, WSFL, and recently BPEL4WS Unfortunately, these efforts leave us a long way from seamless interoperation Researchers in the Semantic Web community have taken up this challenge proposing top-down approaches to achieve aspects of Web Service interoperation Unfortunately, many of these efforts have been disconnected from emerging industry standards, particularly in process modeling In this paper we take a bottom-up approach to integrating Semantic Web technology into Web services Building on BPEL4WS, we present integrated Semantic Web technology for automating customized, dynamic binding of Web services together with interoperation through semantic translation We discuss the value of semantically enriched service interoperation and demonstrate how our framework accounts for user-defined constraints while gaining potentially successful execution pathways in a practically motivated example Finally, we provide an analysis of the forward-looking limitations of frameworks like BPEL4WS, and suggest how such specifications might embrace semantic technology at a fundamental level to work towards fully automated Web service interoperation

Analysis of Web Services Composition Languages: The Case of BPEL4WS

Abstract: Web services composition is an emerging paradigm for application integration within and across organizational boundaries. A landscape of languages and techniques for web services composition has emerged and is continuously being enriched with new proposals from different vendors and coalitions. However, little effort has been dedicated to systematically evaluate the capabilities and limitations of these languages and techniques. The work reported in this paper is a step in this direction. It presents an in-depth analysis of the Business Process Execution Language for Web Services (BPEL4WS) with respect to a framework composed of workflow and communication patterns.

Web services: been there, done that?

Abstract: Web services can be defined as loosely coupled, reusable software components that semantically encapsulate discrete functionality and are distributed and programmatically accessible over standard Internet protocols. Web services have received a lot of hype, the reasons for which are not easily determined. Some of their benefits might even seem to waste away, once we touch on the nitty-gritty details, because Web services per se do not offer a solution to underlying problems. The contributions included in this section delve into some of these issues, including: pitfalls of workflow issues; structuring procedural knowledge into problem-solving methods; discussing how a low initial entry barrier and simple technology are balanced against the long-term goal of easy integration; including semantics in a Web service modeling framework; and building on new kinds of applications such as grid enterprises.

Chaining geographic information Web services

Abstract: Client-coordinated, static, or mediated chaining of GIS Web services enables easier on-demand access to customized geographic information.