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A didactic project is being developed using multimedia techniques at the Physics Department of the University of Bologna to help both students and teachers. The ISHTAR WWW server comprises several courses on different chapters of physics and a set of tools for helping with the didactical activities. The level of the courses is adapted for students in their last years at high school and in their first years at university, and it is especially designed for students of the life sciences.

We present here the preliminary results of the active measurements of Internet traffic. The main goal is the measurement of the effectiveness of hierarchical cache developed last years in a number of countries using Squid software. The passive measurements could not give any conclusive answer. The procedure of the active measurements was developed for that reason. First, we use active measurements (experiments) of Internet traffic sending the http-requests from the log files. This give possibility to perform the comparative measurements which is usually more accurate. Next, more sophisticated procedure using triangle of cache servers, one working as the only manager for the two others, which could be setup differently and, typically, serve only odd and even queries respectively was proposed. This procedure, probably, is the most precise experimental setup for the comparative study of server strategies could be done on the basis of standard hardware and software.

This report presents the status of the use of World-Wide Web (WWW) in High Energy Physics (HEP) experiments. The use of WWW in general, for ‘Online Datataking Systems’ and for ‘Offline Analysis Systems’ is discussed. In each of these cases the current use and a possible outlook for the future is described. Statistics on the actual use of WWW in HEP experiments as well as its current problems and future needs are also presented.

In this brief paper we present a prototype of a an On-line hypermedia newspaper, the first example of daily electronic publishing in Italy, based on the results of a collaboration between CRS4 and L’UNIONE SARDA. The on-line newspaper (text and picture) is created by automatic retrieval, compression, transmission and conversion of newspaper data. The prototype is under development and currently allows automatic hypertextual links, article retrieval facilities and a simple mechanism for creating a personal newspaper. Some HyperText Markup Language (HTML) pages, are shown to give an impression of the prototype.

Since the introduction in 1993 of the World Wide Web and the associated multimedia technologies numerous projects are underway introducing the new tool into introductory physics teaching. This paper will describe two such undertakings: The Cockpit Physics project at the United States Air Force Academy and the WebPhysics project at Indiana University Purdue University at Indianapolis.

The World Wide Web originated within the high-energy physics community from the need to exchange documentation in an efficient way. It can be used easily to produce and maintain didactic material for teaching physics. The material can be made accessible via the network in hypertext form, comprising text, pictures, animations, audio files. For didactic applications in physics, the capability of an interactive link, beyond the use of simple electronic forms is necessary. This was not foreseen in the original WWW protocol, and it has been developed in an application presented here to simulate a series of measurements in a diffusion process in solutions. The recent introduction of the Java language offers a natural way to create new powerful interactive Internet applications. We are currently developing and testing Java powered didactic applications.

A digital city is a social information infrastructure for urban life (including shopping, business, transportation, education, welfare and so on). We started a project to develop a digital city for Kyoto based on the newest technologies including cooperative information agents. This paper presents an architecture for digital cities and shows the roles of agent interfaces in it. We propose two types of cooperative information agents as follows: (a) the front-end agents determine and refine users' uncertain goals, (b) the back-end agents extract and organize relevant information from the Internet, (c) Both types of agents opportunistically cooperate through a blackboard. We also show the research guidelines towards social agents in digital cities; the agent will foster social interaction among people who are living in/visiting the city.

The amount of information available to us via the Web has increased enormously over the last few years. Even more, it seems that we are more and more dependent on this Web information in our day to day lives. Often we retrieve this information by querying the Web: data resources found on the web may provide the information that we are looking for. This implies that the Web may be seen as an information market: authors supply information and searchers may find it. In this article we present a formal reference model for the syntactic aspects of the information market. We explore the information landscape using a modeling approach. An important part of this model is a (syntactic) framework for transformations, which allows us to deal with the heterogeneity of the data resources found on the Web. Last but not least, we attempt to give an outline how our model may lead to a better understanding of how information is supplied via the Web. For this we use an example from the field of information retrieval.

The Internet revolution has made an enormous quantity of information available to a disparate variety of people. The amount of information, the typical access modality (that is, browsing), and the rapid growth of the Net, force the user, while searching for the information of interest, to dip into multiple sources, in a labyrinth of millions of links. Web-at-A-Glance (WAG) is a system allowing the user to query (instead of browsing) the Web. WAG performs this ambitious task by constructing a personalized database, pertinent to the user's interests. The system semi-automatically gleans the most relevant information from a Web site or several Web sites, stores them into a database cooperatively designed with the user, and allows her/him to query such a database through a visual interface equipped with a powerful multimedia query language. This paper presents the design philosophy, the architecture and the core of the WAG system. A prototype WAG is being implemented to test the feasibility of the proposed approach.

The World Wide Web serves as a leading vehicle for information dissemination by offering information services, such as product information, group interactions, or sales transactions. Three major factors affect the performance and reliability of information services for the Web, namely the distribution of information which has resulted from the globalization of information systems, the heterogeneity of information sources, and the sources' instability caused by autonomous evolution. This paper focuses on integrating existing information sources, available via the Web, in the delivery of information services. The primary objective of the paper is to provide mechanisms for structuring and maintaining domain models for Web applications. These mechanisms are based on conceptual modeling techniques, where concepts are being defined and refined within a metadata repository through the use of instantiation, specialization and attribution. Also, active databases techniques are exploited to provide robust mechanisms for maintaining a consistent domain model in a rapidly evolving environment, such as the Web. Therefore, the main contribution of the paper lies in the provision of an architecture for semi-automatic generation and maintenance of user-oriented, semantic-based domain models that describe distributed heterogeneous information sources.

The amount of online information in Chinese and the number of Chinese Internet users have been increasing tremendously during the past decade. Since Chinese language is significantly different from English, techniques that have been developed for retrieving information from English Web documents cannot be directly applied to retrieve information from Chinese Web documents. In order to provide high-performance access of Chinese information on the Web, we have developed a Chinese Web query engine that (i) extracts (hierarchical) data of interest from Chinese HTML tables using an information extraction tool called semantic hierarchy, (ii) allows the user to submit queries in Chinese using a menu-driven user interface, and (iii) processes the user's queries (as Boolean expressions) to generate the correct results. Our query engine supports various groups of information that are categorized into various subject areas, such as car ads, house rentals, job ads, stocks, university catalogs, etc. We have tested our information extraction tool on two application domains, car-ads and house-rental. The average F-measure on extracting Chinese data from these two application domains is above 90%. More importantly, our query engine can easily be configured and internationalized to become a worldwide, multilingual query engine with minor changes in system settings on PCs running Windows operating systems.

Multimedia software engineering is an emerging area combining software engineering, multimedia computing, visual languages and visualization. We can view multimedia software engineering from two different, yet complementary, perspectives: (1) to apply multimedia computing, visual languages and visualization to the practice of software engineering; and (2) to apply software engineering principles to the development of multimedia applications and systems. This chapter surveys some of the approaches and recent advances in multimedia software engineering.

This paper proposes automatic generation of animated weather reports, where a virtual human performs as a weatherman, as an example of automated TV-like program production. An input to our prototype system is a set of (location, time, weather)-type weather forecast data. The system then summarizes the data and makes a weather report scenario in the form of speech texts with embedded commands, most of which relate to the virtual weatherman's body language. From this command-embedded speech text, our virtual human presenter system makes the virtual human agent act as a weatherman with the weather charts in real-time 3D animation synchronized with speech outputs. When the system runs on a Web server, on-demand speech-text generation enables us to watch personalized and up-to-the-minute weather reports on the Web.

The paper studies database publishing technologies based on the WWW. The dramatic progress of the Internet, especially the WWW, makes it possible for people to share database information in a very large scale. Database publishing is an important application in this area and it involves the key technologies, such as the HTTP protocol, server technology, client browser technology, markup language HTML, etc. Typically, there are two means to publish databases on the web: CGI-based and Java-Based. This paper analyzes the advantages and disadvantages of the two methods. Then, it puts forward an approach to database publishing based on a new model: the extension of HTTP. The result of a preliminary evaluation shows that the new model is an efficient approach.