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Vehicles are becoming part of the Internet, either as a terminal in a mobile network, as a network node or as a moving sensor (providing environmental, car status or video information). Interest of vehicles' passengers in location-based information is steadily growing. Moreover drivers and passengers may like to receive information about traffic jams or accidents in their vicinity, or chat with other vehicle's passengers. Enabling communication among automobile nodes (cars) is not a straightforward task. Such nodes form an extremely dynamic ad hoc network, and this presents some technical challenges. One essential characteristic of such networks is that the available services are in principle unknown to a node. A Dynamic Discovery Service (DDS) protocol to discover nodes is needed.

Distributed Computing systems consist of several processors that interact and cooperate with each other by message passing. These distributed systems provide many attractive features such as fault tolerance, resource sharing, high reliability and high throughput. These features make distributed systems good candidates for many real time applications such as aircraft, space crafts and automotive control. Car Industry is striving to provide reliable and cost effective Computing systems for their automobiles. As the number of processors increases in a vehicle, the demand increases to provide a reliable Computing system for the automotive. Therefore, it is important to develop specialized distributed Computing systems for this type of applications taking into consideration reliability as well as cost of the system. In this paper, a distributed Computing system architecture has been proposed for automotive applications.

Automotive electronics can be divided into subsystems according to their functions and physical locations Employing this concept, a hierarchical architecture of automotive electronics may be evolved In this paper a hierarchical fault tolerant distributed processing system has been introduced The system consists of a central controller (CC), m subsystems, a main bus and a shared memory module Each subsystem consists of n processors, one smart sensor group and one smart actuator group The central controller maintains the performance history of every processor in system In case of a processor's failure, the CC assigns the tasks of the faulty processor to another processor within the same subsystem Reliability, which is the probability of a correctly working system for an interval of time [t-t0], has been evaluated An algorithmic approach based on the truth table method has been developed for evaluating the reliability of the proposed hierarchical architecture A comparison of the reliability calculation has been done between the proposed architecture and a system without fault tolerance capability The results show that the proposed architecture provides better reliability

Process temperature profiles of a two-component rigid poly(urethane-isocyanurate) foam system were studied and compared with the predictions of a one-dimensional numerical simulation. This model is based on experimentally determined thermophysical properties including thermal diffusivity, enthalpy of reaction, and rate of reaction. Temperature profiles were measured at three positions within the foam and at the foam surface for mold temperatures of 25°C and 55°C. High rate of reaction and heat of reaction, along with low thermal diffusivity, cause temperatures near the foam center to be insensitive to mold temperatures for thick samples. Thermal analysis and spectroscopic methods were used for determination of thermophysical properties. Temperature dependent heat capacity was evaluated using dynamic DSC. Reaction kinetics were studied using FTIR and isothermal DSC measurements.

Applications of micro-electromechanical systems (MEMS) in automobiles are fairly recent. The two most common examples of MEMS use in automobiles are in crash sensing for airbag deployment, and in manifold absolute pressure sensing. There are, however, several other areas where MEMS devices are expected to replace more traditional technologies within the next few years. MEMS devices/systems (e.g. sensors and actuators) have several vital advantages over more traditional technologies. Because of highly reliable batch processing techniques, large volumes of highly uniform devices can be produced at relatively low unit cost. Since MEMS have virtually no moving parts to wear out, they are extremely reliable and long lasting. With the advent of microprocessor compatibility imposed on many automotive sensor/actuator applications, silicon based MEMS sensors will have a very efficient interaction with the controlling microprocessors.

In the near future, vehicles are expected to become a part of the Internet, either as a terminal in a mobile network, as a network node, or as a moving sensor (providing environmental information, cars status, streaming video, etc.) or a combination of the three. This is partly due to the steadily growing interest of vehicles' passengers in location-based information. Drivers and passengers that would want to receive information about traffic jams or accidents in their vicinity will likely be interested in accessing Internet services from within the vehicular network. Access can be gained by using roadside installed Internet Gateways (IGs), which are able to communicate with the vehicles. When the car network is connected to the Internet, it is important for the vehicle to detect available gateways providing access to the Internet. Therefore, a gateway discovery mechanism is required.