Policy support for call control

The need for policies to control calls is justified by the changing face of communications. It is argued that call control requires distinctive capabilities in a policy system. A specialised policy language called APPEL (ACCENT Project Policy Environment/Language) has therefore been developed for this purpose. However, the policy language is cleanly separated into a core plus specialisations for various application domains. The paper describes both the foundation and the call control ontologies. Sample policy examples are provided to illustrate use for call control. The paper also presents the policy system architecture in which the policy language is interpreted. The components of the policy system are described, particularly the policy server and the policy wizard.     

An Object-Oriented Framework for Loop Parallelization

Generation of efficient parallel code is a major goal of a well-designed and developed parallelizing compiler. Another important goal is portability of both compiler system and the resulting output source codes. The various choices of current and future parallel computer architectures as well as the cost of developing a parallelizing compiler make portability a very important design goal. Since the design of parallelizing compilers is considerably move complex than designing conventional compilers, it is very important to achieve both efficiency and portability. To meet this dual goal, we have investigated the application of object oriented design to parallelizing compilers. Our parallelizing compiler design is based on abstractions of intermediate representations of loops and their class definitions. In this paper, we address the problem of loop parallelization and propose a framework where the loop parallelization process is divided into three phases and the optimization of loops is performed via a cyclic application of these three phases. The class of each phase is hierarchically derived from intermediate representations of loops. This facilitates the portability of the resulting parallelizing compilers. Furthermore, one of the phases uses a reservation table of hardware resources in order to obtain optimized parallel programs for given hardware resources. The validation of the proposed framework is given through the application of the object oriented design on an example program which is then parallelized efficiently.     

Developing Knowledge-Based Intelligent Multimedia Tutoring Systems Using Semantic Content-Based Modelling

The complex nature of semantic video and audio content has made multimedia difficult to use within the traditional architecture of a knowledge-based intelligent tutoring system (ITS). This paper investigates how multimedia syntax and semantics may be integrated into the confines of the knowledge-based ITS architecture so as to develop a knowledge-based intelligent multimedia tutoring system (IMTS). The paper contributes a semantic content-based model that can be used for this purpose. Multimedia frames (m-frames) are used as the framework by which the syntactic and semantic information is represented within the model. The paper discusses how IMTSs may be developed using the model, and then demonstrates the use of our approach in the development of ARISTOTLE, an IMTS for teaching young children basic zoology.     

Algorithms for Fuzzy Segmentation

Fuzzy segmentation is an effective way of segmenting out objects in pictures containing both random noise and shading. This is illustrated both on mathematically created pictures and on some obtained from medical imaging. A theory of fuzzy segmentation is presented. To perform fuzzy segmentation, a ‘connectedness map’ needs to be produced. It is demonstrated that greedy algorithms for creating such a connectedness map are faster than the previously used dynamic programming technique. Once the connectedness map is created, segmentation is completed by a simple thresholding of the connectedness map. This approach is efficacious in instances where simple thresholding of the original picture fails. Received: 22 October 1998?Received in revised form: 22 November 1998?Accepted: 2 December 1998     

新闻动态Q＆A Kevin Sweeney

我们与著名的年轻Flash开发人员进行了一次谈话，他很幸运地在Fantasy Interactive的纽约办公室找到了一份工作。     

Trends in cigarette smoking: the Minnesota Heart Survey, 1980-1982 through 2000-2002.

This paper reports population-based secular trends in smoking prevalence and tobacco exposure among smokers. The Minnesota Heart Survey (MHS) assessed smoking in probability samples in the seven-county Minneapolis-St. Paul metropolitan area. Five surveys were conducted in 1980-1982, 1985-1987, 1990-1992, 1995-1997, and 2000-2002 using similar sampling strategies and consistent protocols. Participants were metropolitan area residents of Minnesota, aged 25-74 years, with the addition of 75-84-year-olds in the last three surveys. In men, age-adjusted self-reported prevalence of current smoking steadily declined from 32.9% in 1980-1982, to 23.0% in 1995-1997, and to 20.6% in 2000-2002. In women, self-reported smoking was 31.8% in 1980-1982, 18.5% in 1995-1997, and 19.5% in the latest survey. Age-adjusted self-reported quantity of cigarettes consumed among smokers declined over the same period. Changes from 1995-1997 to 2000-2002 were not significant. Compared with Whites, Black participants had higher levels of smoking and later onset of the decline in smoking prevalence. A decline in smoking prevalence seems to have leveled off or reversed between the two most recent survey periods (1995-1997 through 2000-2002). Focus on smoking cessation should continue, especially in the subpopulation that smokes more than the majority.     

NaraView: An Interactive 3D Visualization System for Parallelization of Programs

For effective use of parallelizing compilers, an interactive environment which allows users to find more parallelism is needed. As the first step towards building such an environment, we have developed a program visualization system named NaraView. In this paper, we describe two visualization methods in NaraView. One is Program Structure View which illustrates the hierarchical loop structure of a given program and suggests which parts of the program can be parallelized. Another is the Data Dependence View which visualizes each data dependence on every variable or array element which is accessed in a specific loop. By using these views, users can easily understand which part of the program can be parallelized further. We also show several examples to demonstrate the efficiency of these methods.     

Virtual biofuels—A cheaper,better, faster alternative?

This viewpoint article offers the proposition that purpose-grown biomass buried in landfills constitutes a “virtual” biofuel that is more practical, economic, and immediate than the use of actual biofuels from cellulosics. While not a permanent solution, it may be a useful bridge to the hoped-for era of actual biofuels prior to the time technology for economically converting cellulosics to actual liquid biofuels is realized.