SAC 2000: Electronic Proceedings

WWW Applications Track

Track chair:Robert Inder, University of Edinburgh
The following papers submitted to the WWW Applications Track in SAC 2000 are available on-line:
Web Access to Environmental Databases: a Database Query and Presentation System for the UK Environmental Change Network.
Susannah Clare RennieCentre for Ecology and Hydrology, Merlewood Research Station, Windermere Road, Grange-over-Sands, Cumbria, LA11 6JU.
Amanda Lane Centre for Ecology and Hydrology, Merlewood Research Station, Windermere Road, Grange-over-Sands, Cumbria, LA11 6JU.
Mike WilsonCentre for Ecology and Hydrology, Merlewood Research Station, Windermere Road, Grange-over-Sands, Cumbria, LA11 6JU.

This paper describes the development of an interface to an environmental monitoring database using the World Wide Web (WWW) as a front-end. The Environmental Change Network (ECN) is the UK’s long-term integrated environmental monitoring program. Many of ECN’s users require access to ECN’s data for reporting purposes. Since these users are unfamiliar with the use of the Oracle Relational Database Management System used by ECN and the structure of the data in the ECN database, they require guided access to the data. Additionally, these users generally do not require access to high-resolution data. They need access to summary data in order to view trends, display the data for reporting and as an aid to making policy decisions. To support these users, ECN has developed an interface to its summary data over the WWW ( The system allows users to query the ECN database by site, measurement and date range and displays the data in cross-tabulations or graphs. Data may also be downloaded to the users local machine via electronic mail.

Full paper
Assurance Protocols and Small Web Retailers
Gordon Edward LYONNational Institute of Standards and Tech.

Many Web areas are in an early technological period of rapid evolution and intense competitive selection. Nowhere is this truer than with electronic commerce. While much is being considered today for business-to-business transactions, the Web also represents a marvelous opportunity for small retail establishments. However, the needs of small establishments differ from those of larger firms. In particular, customer assurance is very important. Several assurance protocols are examined for their utility to small retail sellers on the Web. One new possibility involves using bankcard records to build assurance ratings.

Full paper
How to Visit Data with OTHY

Hypermedia design has received considerable attention and methodologies appeared to conceive hypertexts, especially to alleviate the well-known disorientation problem. The Object To Hypermedia (OTHY) approach that we propose takes into account object-orientation to balance page customisability with respect to different types of objects with uniformity within a single class. In this paper, we again take advantage of this trade-off to introduce a generalisation of the tour concept that is able to fit several needs, mostly directed to traditional and new database requirements, but also demanded by end-users to better visualise data. We developed a prototype with Java to implement these concepts.

Full paper
Efficient and Flexible Web Access to Art-Historical Image Collections
Matthias WagnerUniversity of Augsburg
Stefan HollandUniversity of Augsburg
Werner KiesslingUniversity of Augsburg

Modern object-relational database systems are capable of managing multimedia data, e.g. image, video and audio. In this paper we study how such universal database systems can be used for implementing self-tuning and adaptive digital image archives. The presented framework is based on the idea that multimedia objects are often stored redundantly to support broadest system access for diverse clients from heterogenous environments. There is a large variety of ways to store and deliver multimedia data in various formats. Partitioning the data into formats that are physically stored in the database and those that are converted into any delivery format on-demand poses a nontrivial optimization problem. We present a new optimization algorithm which has been implemented and evaluated with the commercial database system DB2 Universal Database from IBM. The work is part of the HERON project, a project committed to the creative use of computer science and technology to advance the study of arts and humanities.

Full paper
Adaptive Intelligent Hypermedia using XML
Maria Elena BonfigliUniversity of Bologna
Giorgio CasadeiUniversity of Bologna
Paola SalomoniUniversity of Bologna

In this paper we discuss the problems of developing Web-based Adaptive Hypermedia (AH) for engineering education using Extensible Markup Language (XML). AH systems are capable of altering the presentation of the content of the hypermedia on the basis of a dynamic understanding of the individual user. The user profile can be collected in a user model, while the knowledge about the domain (the content of the hypermedia) can be represented in the form of a concept-based domain model. So we have defined two different markup languages using XML: the former for structuring the domain model and the latter for describing the student model. These languages can be easily extended and authored, with the result of obtaining a simple methodology for data structuring in the field of Web-based educational AH.

Full paper
Supporting Compositional Reuse in Component-Based Web Engineering
Martin GaedkeTecO, University of Karlsruhe
Jörn RehseTecO, University of Karlsruhe

The World Wide Web's anticipated scope as an environment for knowledge exchange has changed dramatically. Without major modifications to its primary mechanisms the Web has turned into a platform for distributed applications. The originally simple and well-defined coarse-grained implementation model of the Web now hinders Web application development. Fine-grained development artifacts, design patterns, and other well-established Software Engineering methods are hard to reuse in the Web after they have found their way into implementation resources. The application of Software Engineering practice to development for the Web, which is also referred to as Web Engineering, and especially the systematic reuse of components for Web-application development at low-costs is a main goal to achieve. This paper presents a systematic approach to code reuse with the WebComposition Repository, which is an essential tool for retrieval and classification of large component sets. The Repository's architecture is crafted to support multiple representation and classification approaches. It facilitates reuse in component-based Web Engineering.

Full paper
A Lightweight, Message-Oriented Application Server for the WWW
Ralf-Dieter SchimkatWilhelm-Schickard Institute for Computer Science, University of Tuebingen, Germany
Stefan MuellerWilhelm-Schickard Institute for Computer Science, University of Tuebingen, Germany
Wolfgang KuechlinWilhelm-Schickard Institute for Computer Science, University of Tuebingen, Germany
Rainer Krautterdebis Systemhaus Industry (Competence Center Document and Workflowmanagement) CU DMS / PP

In this paper, we present a lightweight system that loosely couples and integrates any kind of source systems with information retrieval capabilities. The system provides mechanisms for a rapid integration of source systems into the World Wide Web (WWW), allowing the generation of configurable collections of individual, heterogeneous source systems. The proposed system is based on a lightweight, message-oriented application server and an object-oriented client framework to provide an uniform, Java-based graphical user interface. The system offers application middleware functionalities that solve issues such as limited bandwidth and scalability of both sides (WWW user clients and backend server systems) in a generic manner. Already integrated source systems include the system PROGRESS (a method base system for mathematical algorithms with functionalities for server-side computing) and SPECTO (an XML-based, distributed monitoring system).

Full paper
Controlling Transmission Order of Inline Objects for Effective Web Page Publishing
Tadashi NakanoOsaka University
Kaname HarumotoComputation Center, Osaka University
Shinji ShimojoComputation Center, Osaka University
Shojiro NishioOsaka University

Due to the increasing popularity of the Internet, the WWW (World Wide Web) has become the most popular way to distribute multimedia contents. In the WWW, impressive information can be provided by embedding a large number of inline objects such as images in a WWW page. Since these inline objects are generally presented on a WWW browser with the order of transmission, the transmission order of inline objects becomes very important, especially for users accessing the Internet with a low-speed link such as a dial-up line. In this paper, we propose a page transmission mechanism which allows content providers to specify the transmission order of inline objects in WWW pages. First, we define a language to specify the transmission order of inline objects. We then discuss how we can implement the transmission order control, and propose a new protocol, HTSP (Hypertext Streaming Protocol), which realizes efficient transmission of ordered inline objects.

Full paper
A Context-Based Navigation Paradigm for Accessing Web Data
Wilfried LemahieuK.U.Leuven

This paper presents a context-based navigation paradigm, so as to overcome the phenomenon of user disorientation in a Web environment. Conventional navigation along static links is complemented by run-time generated guided tours, which are derived dynamically from the context of a user’s information requirements. The result is a two-dimensional navigation paradigm, which reconciles complete navigational freedom and flexibility with a measure of linear guidance. Consequently, orientation is improved through reduced cognitive overhead and an increased sense of document coherence.

Full paper
Nu.M.E.: a WWW Virtual Historic Museum of the City of Bologna
Maria Elena BonfigliUniversità degli Studi di Bologna
Luigi CaloriVisIT Lab - CINECA
Antonella GuidazzoliVisIT Lab - CINECA

Nu.M.E., the WWW Virtual Historic Museum of the City of Bologna, is a "four-dimensional" web environment characterized by specific navigation and orientation tools, using virtual reality and interaction techniques to represent VRML real scenarios (the city of Bologna as it is today), VRML artificial scenarios (the city recreated as it was in the past centuries) and their integration. The idea is to realize a link between the concepts of "culture" and "technological innovation" by the creation of a venue being a cultural, scientific and technological meeting point that is both a WWW application and a place in which the city can reclaim its collective identity. On the one hand there is the traditional concept of the museum as a physical venue, and, on the other hand, there is also the opportunity to expose information we have about the historic and urban development of the central area of the city, to visualize it by means of virtual reality, and to distribute it with the use of internet. This new, conceptual reconstruction of the museum allows visitors to look back into time "witnessing" the historical and urban development of the city from the end of the first millennium to the city as it is today. Nu.M.E. can provide also a powerful tool for historic researchers to experiment with and test different hypotheses and to direct access to historic resources necessary for studying the history of the city. Moreover, it offers support for city and regional planners in the decision making process in relationship to urban development, city planning and management, serving as a virtual "test site" for viewing the city in the future.

Full paper
Syndication with JML
Robert BartaBond University, Gold Coast, Australia
Markus SchranzErnst&Young, Vienna, Austria

Content publishing and republishing has become daily business on the Internet. Zillions of information sources are pushed to the Web by thousands of service providers using hundreds of different publishing and republishing systems. Despite the increasing need, high quality tools are rare and content management severely lacks support by sophisticated approaches. To introduce structure and manageability into publishing and republishing of information on the Web we created JML, the Jessica Markup Language. JML is a textual language for specifying and implementing complex Web applications. Its language features support the separation of content, structure and layout by defining documents as objects, layout as classes and complete Web sites as object collections. Since JML is declarative by nature, it is not only usable for the generation of new documents from more or less structured content, but also for the analysis of such documents. This allows to republish specific content for other channels as will be necessary for handheld computers or GSM devices in XML based repositories in an syndication effort.

Full paper
The Evolution of the DARWIN System
Joan D. WaltonNASA/Ames Research Center
Robert E. FilmanCaelum Research Corporation
David J. KorsmeyerNASA/Ames Research Center

DARWIN is a web-based system for presenting the results of wind-tunnel testing and computational model analyses to aerospace designers. DARWIN captures the data, maintains the information, and manages derived knowledge (e.g. visualizations) of large quantities of aerospace data. In addition, it provides tools and an environment for distributed collaborative engineering. We are currently constructing the third version of the DARWIN software system. DARWIN’s development history has, in some sense, tracked the development of web applications. The 1995 DARWIN reflected the latest web technologies–CGI scripts, Java applets and a three-layer architecture–available at that time. The 1997 version of DARWIN expanded on this base, making extensive use of a plethora of web technologies, including Java/JavaScript and Dynamic HTML. While more powerful, this multiplicity has proven to be a maintenance and development headache. The 2000 version of DARWIN will provide a more stable and uniform foundation environment, composed primarily of Java mechanisms. In this paper, we discuss this evolution, comparing the strengths and weaknesses of the various architectural approaches and describing the lessons learned about building complex web applications.

Full paper
Prototyping Web Applications
Mario BochicchioDept. Innovation Engineering
Roberto PaianoDept. Innovation Engineering

Design of large WWW sites can be a very complex task if not supported by a suitable theoretical model. A good structural design model, in fact, is able to precisely define the information structures of this kind of multimedia applications and the related navigation patterns. Moreover, through a good design model the designer is able to precisely formulate his/her ideas, discuss them and revise them, without actually starting any implementation. The modeling activity necessarily implies rough initial ideas, revisions, versions, etc. For these reasons a design-supporting environment, allowing the modeler to be effective and precise, is essential. Moreover the site prototyping, starting from the structural design model, is very helpful for at least three reasons: non-expert “readers” can’t fully grasp what the designed application is about, unless they can see it. The second reason is that even expert designer, once the design is pretty mature, may need to visualize the outcome of the design itself, before going to actual implementation. The third reason is that “visual designers” need also to step in their own idea, to develop it and try it, before completing the design process. In this paper we do not discuss design models, which are a research field on its own. The paper discusses, instead, a design/prototyping environment and presents the relevant features of JWeb, a design/prototyping environment being developed as a joint effort from Politecnico di Milano and Università di Lecce, in Italy.

Full paper
Modeling of Time and Document Aging for Request Prediction - One Step Further
Ernst-Georg HaffnerInstitute of Telematics, Trier, Germany
Uwe RothInstitute of Telematics, Trier, Germany
Thomas EngelInstitute of Telematics, Trier, Germany
Christoph MeinelInstitute of Telematics, Trier, Germany

An important problem of prediction algorithms is the treatment of document aging and the change in user request behavior. This paper proposes a possibility to model time in a standard prediction scenario and analyses the results in a test environment. The knowledge of characteristics in the generated test sessions is also applied to real user logs to determine explicit values of implicit access log information. With this technique, client server communication on the Internet should be improved.

Full paper
Integrating Heterogeneous Data Sources using the COIL Mediator Definition Language
Christian OchUniversity of Colorado at Boulder
Roger KingUniversity of Colorado at Boulder
Richard OsborneUniversity of Colorado at Boulder

Megaprogramming, module interconnection languages, and mediator-based approaches built on standard distributed object technologies such as CORBA and DCOM have provided promising advances in enterprise-level data integration. These distributed object technologies, however, still require relatively low-level, technology-dependent implementations to achieve object (or module) interconnection, communication, and coordination. The Component Object Interconnection Language (COIL) is a language designed specifically to facilitate rapid and flexible data integration through high-level object interconnections. COIL is an extensible language, with both declarative and imperative aspects. It has been designed to provide broad functionality in declaring and controlling structural and semantic data integration, and includes constructs for specifying updates, constraint enforcement, and update propagations. This paper presents an overview of COIL and a stylized example showing an application of the COIL language and its components.

Full paper
Cooperative Planning: Using the Web for Cooperation in Architectural Planning
Hilda TelliogluAssociated Professor

This paper describes a prototype called ``CoPlan'' from the users' point of view. CoPlan supports cooperation between distributed professionals in architectural planning. CoPlan uses Web and database technologies to create a common information space between planners and producers. It offers several applications derived from users' specific needs, such as data access and decision support tools. These applications have been developed by applying methods of cooperative prototyping. CoPlan is customizable by users, is integrated with companies' present infrastructures and is based on Open Source Software. The architectural design practices CoPlan has to support are based on the notion of open planning. Open planning asks for a conceptual shift from working with fixed elements or solutions to working with place-holders which represent open design decisions. Place-holders are defined by several parameters and relations between these parameters.

Full paper
The Mobile Agent Technology to Support and to Access Museum Information
Paolo BellavistaDept. Electronics, Computer Science and Systems (DEIS) - University of Bologna
Antonio CorradiDept. Electronics, Computer Science and Systems (DEIS) - University of Bologna
Andrea TomasiDip. Ingegneria dell'Informazione - University of Pisa

The global scenario put together by communication networks determines new opportunities towards the realization of Internet-based distributed services in many complex and composite application areas, such as the access to museum information. Solution complexity mainly stems from the heterogeneous representation formats of data, their geographical distribution, the large number of data sources involved, and the user requirements for personal customization and optimization of the accessed services. The paper claims that the realization of flexible museum information access services require a middleware-level approach and the implementation of a distributed support infrastructure. Within the MOSAICO project, we have realized the VM (Virtual Museum) framework on top of the SOMA (Secure and Open Mobile Agent) programming environment. Mobile agents have been chosen for their intrinsic properties of autonomy, asynchronicity, dynamicity of distribution, and adaptability to available system resources. We have designed the VM to accommodate different usage scenarios: VM users can play different roles with different expertise levels; they can ask the VM infrastructure for differently complex features, from simple Web accessibility to user accounting for data resource consumption, from data customization via user profiling to automatic update of subscripted query results. The first prototype, apart from the feasibility of the approach, has already shown the potential and the flexibility of the mobile agent infrastructure to adapt to both different user requirements and different resource availability.

Full paper
Page generated: 17:59 14 Feb 2000 by