Abstract

This paper presents a set of tools supporting the development of interactive systems using two different notations. One of these notations, called ConcurTaskTrees (CTT), is used for task modelling. The other notation, called Interactive Cooperative Objects (ICO), is used for system modelling. Even though these two kinds of models represent two different views of the same world (users interacting with interactive systems), they are built by different people and used independently. The aim of this paper is to propose the use of scenarios as a bridge between these two views. On the task modelling side, scenarios are seen as possible traces of activities, while on the system side, they are viewed as traces of actions. This generic approach is presented in a case study in the domain of Air Traffic Control. Document type: Part of book or chapter of book

Abstract

The proposed paper describes a compression test analysis of JBIG standard algorithm. The aim of such work is to proof the effectiveness of this standard for images acquired through scanners and processed into a printer pipeline. The main issue of printer pipelines is the necessity to use a memory buffer to store scanned images for multiple prints. This work demonstrates that for very large scales the buffer can be fixed using medium compression case, using multiple scans in case of uncommon random patterns. Document type: Part of book or chapter of book

Abstract

Exploration and analysis of vast empirical data is a cornerstone of the development and assessment of driver assistance systems. A common challenge is to apply the domain specific knowledge to the (mechanised) data handling, pre-processing and analysis process.\r \r Ontologies can describe domain specific knowledge in a structured way that is manageable for both humans and algorithms. This paper outlines an architecture to support an ontology based analysis process for data stored in databases. Build on these concepts and architecture, a prototype that handles semantic data annotations is presented. Finally, the concept is demonstrated in a realistic example. The usage of exchangeable ontologies generally allows the adaption of presented methods for different domains. Document type: Part of book or chapter of book

Abstract

Nowadays, P2P applications are commonly used in the Internet being an important paradigm for the development of distinct services. However, the dissemination of P2P applications also entails some important challenges that should be carefully addressed. In particular, some of the important coexistence problems existing between P2P applications and Internet Service Providers (ISPs) are mainly motivated by the inherent P2P dynamics which cause traffic to scatter across the network links in an unforeseeable way.\r \r In this context, this work proposes a collaborative framework of a BitTorrent like system. Using the proposed framework and based on the exchange of valuable information between the application and network levels, some novel techniques are proposed allowing to estimate and control the traffic impact that the P2P system will have on the links of the underlying network infrastructure. Both the framework and the presented techniques were tested resorting to simulation. The results clearly corroborate the viability and effectiveness of the formulated methods. Document type: Part of book or chapter of book

Abstract

A joint project of the Austrian company Frequentis1 and the Technical University Graz demonstrates the applicability of executable formal models2. The formal method VDM++ has been applied to specify a safety critical voice communication system (VCS) for air-traffic control. Besides the expected improvement of the informal speciffication documents, 64 defects have been found, the efficiency of the system test-cases to cover the functionality of the VCS has been analyzed. In order to get a test-coverage measure, the formal specification has been animated with existing system test-cases using IFAD’s VDMTools. Document type: Part of book or chapter of book

Abstract

Nowadays, P2P applications proliferate in the Internet with distinct utilization contexts, being also an attractive model for the deployment of advanced Internet services. However, there are several undesirable effects that are caused by such applications, raising coexistence problems with Internet Service Providers (ISPs). In this context, using as case study BitTorrent like applications, this work explores a collaborative framework allowing that advanced efforts could be carried on between P2P applications and network level entities. In order to illustrate such framework, several Traffic Engineering (TE) mechanisms are devised in order to align some P2P dynamics with particular objectives pursued by network administrators. The simulation results show that both the proposed framework and corresponding illustrative mechanisms are viable and can effectively foster future research efforts within this field. (undefined) Document type: Part of book or chapter of book