[...]... access to Web databases and Web services We focus on providing a distributed ontology for a meaningful organization of and efficient access to Web databases We dedicate most of our work on presenting a comprehensive query infrastructure for the emerging concept of Web services The core of this query infrastructure concerns the efficient delivery of Web services based on the concept of Quality of Web Service... efficient and uniform querying of Web databases The main focus is on designing a meaningful organization and segmentation of the large information space This research resulted in an ontology based organization of Web databases or distributed ontology for Web databases [72, 30] Such organization of Web databases would filter interaction and accelerate searches in the large space of Web databases Scalability... relationships Individual Web databases join and leave the formed ontologies at their own discretion We first implemented the above ontological organization in WebFINDIT using a healthcare scenario and then in WebDG WebFINDIT [72, 24, 26, 25] is a system for describing, locating and accessing Web databases It offers a Web- centric infrastructure to elicit interoperation of Web databases WebDG [27, 30] enables... massive amount of information, the ever increasing amount of accessible information has made quality information search an arduous task The main impediment has been adding semantics to the Web so that information can be automatically processed The envisioned Semantic Web aims to fulfill this goal [19] In simple terms, the Semantic Web is an extension of the current Web in which information is given well-defined... through the Web [34] They are becoming the foundational infrastructure for different forms of dynamic and semantic- aware interactions on the Web Examples of applications using Web services include e-commerce with all its forms (B2B, B2C, etc.), digital government, wireless applications, and grid computing The Web is evolving from a passive medium for publishing data to a more active platform for conducting... acceptable for most users However, large differences may be seen as a performance degradation for the Web service in delivering its functionalities For that reason, we monitor QoWS for invoked Web services This monitoring would essentially measure the fluctuations of QoWS parameters and give an assessment or rating for the Web service Finally, for a given user request, we may not be able to find a Web service... distributed ontology based organization for Web databases [72, 26] This organization facilitates location and querying of Web databases Web databases are organized and segmented based on simple ontologies that describe coherent slices of the information space The main premise is that Web databases are built to serve specific purposes Distributed ontologies of Web databases are established through a simple... organization of Web services • Autonomy and dynamism – Web services are dynamic and independent entities The query infrastructure cannot mandate any particular behavior on Web services to achieve its goal No cooperation from Web services for optimization purposes may be assumed In addition, adaptation to changes may be necessary while building and executing the service execution plan • Web services competition... Quality of Web Service (QoWS) under which they can deliver those functionalities We need to provide the necessary mechanisms to select the best Web services and combinations of Web services Efficiently querying Web databases and Web services requires to tackle several challenging research issues In the following, we outline those issues that we have addressed in our book (Figure 1.2) • Web databases. .. cooperation [19] A key player in enabling the Semantic Web is the emerging concept of Web services A Web service is a set of related functionalities that can be programmatically accessed and manipulated through the Web Interacting with Web resources, including databases and other information sources, is taking a new direction with the emergence of Web services Data integration has received considerable . y0 w0 h0" alt="" Semantic Web Services for Web Databases Mourad Ouzzani • Athman Bouguettaya Semantic Web Services for Web Databases Foreword by Boulem. 92 6 Current Advances in Semantic Web Services and Web Databases 97 6.1 Web Databases Integration and Efficient Querying 99 6.1.1 Pre -Web Data Integration 99 6.1.2