{"title":"Dynamic data delivery to mobile users","authors":"A. Afonso, Francisco S. Regateiro, Mário J. Silva","doi":"10.1109/DEXA.1999.795154","DOIUrl":"https://doi.org/10.1109/DEXA.1999.795154","url":null,"abstract":"We propose an information push model information dissemination to mobile users, called dynamic channel model. It is a set of extensions to the conceptual models developed for information channels, capturing mobility-specific requirements. These are used for filtering and setting update order priorities for the information that users intend to monitor, which depends on their location and changes as they roam. We also present the architecture of Ubidata, an adaptable framework for information dissemination to mobile systems. We introduce our development process for a class of mobile computing applications operating under an information dissemination metaphor.","PeriodicalId":276867,"journal":{"name":"Proceedings. Tenth International Workshop on Database and Expert Systems Applications. DEXA 99","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115808634","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Integration of diverse hypermedia link servers using request routing","authors":"D. D. Roure, Nigel G. Walker, L. Carr","doi":"10.1109/DEXA.1999.795264","DOIUrl":"https://doi.org/10.1109/DEXA.1999.795264","url":null,"abstract":"Hypermedia link servers are a powerful infrastructure component for creation and delivery of network based information applications. The Distributed Link Service is an established design for a link service on the Internet using the WWW infrastructure and has been exercised in a number of projects. We investigate the provision of such a link service operating over multiple and disparate link servers. We report on an initial experiment which utilised query routing in a laboratory environment with a variety of link servers; the experiment provides proof of concept and suggests particular benefits in the query routing approach to managing the search space. We then discuss the use of table replication and migration to promote scalability, presenting preliminary results from simulations.","PeriodicalId":276867,"journal":{"name":"Proceedings. Tenth International Workshop on Database and Expert Systems Applications. DEXA 99","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133015444","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Multi-party fair exchange with an off-line trusted neutral party","authors":"F. Bao, R. Deng, K. Nguyen, V. Varadharajan","doi":"10.1109/DEXA.1999.795294","DOIUrl":"https://doi.org/10.1109/DEXA.1999.795294","url":null,"abstract":"Recently developed cryptographic techniques make it possible to construct fair exchange protocols with an off-line trusted third party (TTP). The technique is referred to as a verifiable encryption scheme (VES) and proves that a ciphertext is the result of the encryption of a specified value without revealing this value. In this paper we apply the technique to multi-party fair exchange (MPFE) protocols which leads to the trusted neutral party (TNP, it is not the third party in multi-party protocols) involved in the protocol to be off-line. Multi-party fair exchange has been studied by Asokan et al. (1996) and Franklin and Tsudik (1998) where the TNP is on-line. For off-line TNP-based MPFE, the issues are different from that of on-line TNP MPFE. We give a definition of fairness of the MPFE with off-line TNP. We then present our MPFE protocol and prove its fairness.","PeriodicalId":276867,"journal":{"name":"Proceedings. Tenth International Workshop on Database and Expert Systems Applications. DEXA 99","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127400531","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Designing WWW site map systems","authors":"C. Pilgrim, Y. Leung","doi":"10.1109/DEXA.1999.795174","DOIUrl":"https://doi.org/10.1109/DEXA.1999.795174","url":null,"abstract":"Providing an alternative visualisation of the structure of a web site can alleviate many of the usability problems associated with WWW navigation. Whilst site maps are one of the most popular tools utilised by site designers to overcome such problems, little is known about how to design effective site maps. This paper examines some underlying design issues relating to web site maps and then presents an implementation of an experimental site map system demonstrating the application of these principles. This 'SiteTree' system displays a hierarchical abstraction of the site, which provides basic filtering and visualisation controls, including novel \"landmark\" functionality. This paper provides a basis for future development of WWW site maps tools by clarifying existing research and identifying important design issues.","PeriodicalId":276867,"journal":{"name":"Proceedings. Tenth International Workshop on Database and Expert Systems Applications. DEXA 99","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128852343","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Personalizing the Web using site descriptions","authors":"V. Anupam, Y. Breitbart, J. Freire, B. Kumar","doi":"10.1109/DEXA.1999.795275","DOIUrl":"https://doi.org/10.1109/DEXA.1999.795275","url":null,"abstract":"The information overload on the Web has created a great need for efficient filtering mechanisms. Many sites (e.g., CNN and Quicken) address this problem by allowing a user to create personalized pages that contain only information that is of interest to the user. We propose a new approach for personalization that improves on existing services in three significant ways: the user can create personalized pages with information from any site (without being restricted to sites that offer personalization), personalized pages may contain information from multiple Web sites (e.g., a user can create a personalized page that contains not only news categories from her favorite news sources, but also information about the prices of all stocks whose names appear in the headlines of selected news, and weather information for a particular city); and users have more privacy since they are not required to sign up for the service. In order to build a personalization service that is general and easy to maintain, we make use of site descriptions that facilitate access to the data stored in and generated by Web sites. Site descriptions encode information about the contents, structure, and services offered by a Web site, and they can be created semi-automatically.","PeriodicalId":276867,"journal":{"name":"Proceedings. Tenth International Workshop on Database and Expert Systems Applications. DEXA 99","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115381122","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Javier Andrade Garda, Juan Ares Casal, Óscar Dieste Tubío, R. Vázquez, Marta López Fernández, Santiago Rodríguez Yáñez, Luisa Verde
{"title":"Creation of an automated management software requirements environment: A practical experience","authors":"Javier Andrade Garda, Juan Ares Casal, Óscar Dieste Tubío, R. Vázquez, Marta López Fernández, Santiago Rodríguez Yáñez, Luisa Verde","doi":"10.1109/DEXA.1999.795188","DOIUrl":"https://doi.org/10.1109/DEXA.1999.795188","url":null,"abstract":"A software process improvement programme is under way at a Spanish financial institution. A structured methodology, supported by formal and informal techniques and tools, is being established by a methodological support group, as a starting point for the improvement. This paper centres particularly on the methodological and automated management of software requirements analysis. This process was previously performed in a not formal manner, and the most direct consequence was the high costs in maintenance. The methodology developed includes actions to obtain, refine and validate the software requirements. It also includes an organisational Software Requirements Specification (SRS) standard, implemented on a commercial tool which was selected as a result of a formal evaluation process. Additionally, a procedure was defined for working with the SRS and the tool. The results of this practical experience show an improvement in SRS quality, and work is no longer duplicated, since more correct and complete specifications are obtained.","PeriodicalId":276867,"journal":{"name":"Proceedings. Tenth International Workshop on Database and Expert Systems Applications. DEXA 99","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116305924","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Constantinos Spyrou, G. Samaras, E. Pitoura, P. Evripidou
{"title":"Wireless computational models: mobile agents to the rescue","authors":"Constantinos Spyrou, G. Samaras, E. Pitoura, P. Evripidou","doi":"10.1109/DEXA.1999.795155","DOIUrl":"https://doi.org/10.1109/DEXA.1999.795155","url":null,"abstract":"Wireless mobile computing breaks the stationary barrier and allows users to compute and access information anywhere and anytime. However, this new freedom of movement does not come without new challenges. The mobile computing environment is constrained in many ways. Mobile elements are resource-poor and unreliable. Their network connectivity is often achieved through low-bandwidth wireless links. Furthermore, connectivity is frequently lost for variant periods of time. The difficulties raised by these constraints are compounded by mobility that induces variability in the availability of both communication and computational resources. These severe restrictions have a great impact on the design and structure of mobile computing applications and motivate the development of new computing models. To this end, a number of extensions to the traditional distributed system architectures have been proposed previously. These new software models, however, are static and require a priori set up and configuration. This in effect limits their potential in dynamically serving the mobile client; the client can not access a site where an appropriate model is not configured in advance. The contribution of this paper is twofold. First, the paper shows how an implementation of the proposed models using mobile agents eliminates this limitation and enhances the utilization of the models. Second, new frameworks for Web-based distributed access to databases are proposed and implemented.","PeriodicalId":276867,"journal":{"name":"Proceedings. Tenth International Workshop on Database and Expert Systems Applications. DEXA 99","volume":"107 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116364316","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Achieving consistency in mobile databases through localization in PRO-MOTION","authors":"S. Mazumdar, Panos K. Chrysanthis","doi":"10.1109/DEXA.1999.795149","DOIUrl":"https://doi.org/10.1109/DEXA.1999.795149","url":null,"abstract":"There is great need and potential for traditional transaction support in a mobile computing environment. However owing to the inherent limitations of mobile computing, we need to augment the well-developed techniques of database management systems with new approaches. We focus on the challenge of assuring data consistency. Our approach of localization is to reformulate global constraints so as to enhance the autonomy of the mobile hosts. We show how this approach unifies techniques of maintaining replicated data with methods of enforcing polynomial inequalities. We also discuss how localization can be implemented in PRO-MOTION, a flexible infrastructure for transaction processing in a mobile environment.","PeriodicalId":276867,"journal":{"name":"Proceedings. Tenth International Workshop on Database and Expert Systems Applications. DEXA 99","volume":"50 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127131431","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"QoS-aware distributed query processing","authors":"Haiwei Ye, B. Kerhervé, G. Bochmann","doi":"10.1109/DEXA.1999.795305","DOIUrl":"https://doi.org/10.1109/DEXA.1999.795305","url":null,"abstract":"In the environment of wide-area networks such as the Internet, distributed query processing is becoming problematic due to changes of the underlying networks and user requirements. In this new context, conventional query processing strategies with the homogeneous assumption will not work well, because they are unable to adapt to unexpected changes in the performance of the communication networks. In this paper, we address the issue of how to make distributed query processing aware of these changes. We introduce the idea of integrating distributed query processing with quality of service (QoS) management and accordingly illustrate our view of QoS-aware distributed query processing.","PeriodicalId":276867,"journal":{"name":"Proceedings. Tenth International Workshop on Database and Expert Systems Applications. DEXA 99","volume":"159 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127402414","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Trends and future of mobile computing","authors":"A. Rakotonirainy","doi":"10.1109/DEXA.1999.795156","DOIUrl":"https://doi.org/10.1109/DEXA.1999.795156","url":null,"abstract":"Networking homes, offices, cars and hand-held computers is the current trend of distributed mobile computing. The ever growing demand of the enterprise for integrating new technologies and new services requires a generic infrastructure. An infrastructure that allows its components to be accessed, packaged, self described, dynamically configurable, moved over wired or wireless network, deployed either in a workstation or a mobile device from anywhere at anytime. An infrastructure that can be used with new alternatives to current human-machine interfaces applicable in diverse environment.","PeriodicalId":276867,"journal":{"name":"Proceedings. Tenth International Workshop on Database and Expert Systems Applications. DEXA 99","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127451386","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}