The possibility to constitute an interoperability of EFC in the central and eastern Europe

The article describes critical situation concerning implementation of the EFC satellite oriented system in CEEC countries. Situation in the field of practical implementation of GNSS/CN is very critical at present due to lack of valid European standards. There is only one realistic possibility to build up interoperable system - to use “de facto” standards. The idea has been elaborated by expert group for the Ministry of Transport of the Czech Republic

Methods of risk analysis of telematic objels

The paper focuses on basic description of the tunnel as a telematic object and its architecture. Conventional methods of risk analysis of telematic objects are introduced in relation to their safety. New approaches of risk quantification are shown in connection to existing legislation and directives of European Commission

A Motion-aware Data Transfers Scheduling for Distributed Virtual Walkthrough Applications

Data transfers scheduling is an important part of almost all distributed virtual walkthrough (DVW) applications. Its main purpose is to preserve data transfer efficiency and render quality during scene exploration. The most limiting factors here are network restrictions such as low bandwidth and high latency. Current scheduling algorithms use multi-resolution data representation, priority determination and data prefetching algorithms to minimize these restrictions. Advanced priority determination and data prefetching methods for DVW applications use mathematic description of motion to predict next position of each individual user. These methods depend on the recent motion of a user so that they can accurately predict only near locations. In the case of sudden but regular changes in user motion direction (road networks) or fast moving user, these algorithms are not sufficient to predict future position with required accuracy and at required distances. In this paper we propose a systematic solution to scheduling of data transfer for DVW applications which uses next location prediction methods to compute download priority or additionally prefetch rendered data in advance. Experiments show that compared to motion functions the proposed scheduling scheme can increase data transfer efficiency and rendered image quality during scene exploration

Cellular automaton traffic flow model with vehicle type and number of persons

The paper deals with microscopic modeling of the traffic flow using cellular automaton in the Tunnel Simulator based on PLC. Model with lane changing logic is implemented in the SCADA visualization screen of the tunnel with unidirectional two-lane traffic. Tunnel Simulator is able to simulate unexpected events in the road tunnel such as fire, so vehicle type is also included in the traffic model to specify the heat release rate of the fire for car, van, bus and truck fi re scenario. Number of persons in the vehicles and location of the persons in the tunnel are planned to be used as the input for the model for evacuation time estimation