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Polyamide 6(PA6)/hexagonal boron nitride(h-BN) and polyphenylene sulfide(PPS)/graphite composites have been prepared to investigate the possible usage as battery housing materials. The addition of the highly conductive filler improved thermal conductivity of polymer matrix more than 2 times. On the basis of the experimental results and intrinsic material parameters, thermal behavior in a battery pack has been monitored by computational simulation. The heat generated within a cell was readily dissipated as a highly thermal conductive aluminum(Al) was used and thus the temperature was evenly distributed over a whole package. In the case of a battery pack made of polymer or polymer composites, on the other hand, the temperature inside cell is much higher due to the accumulation of heat. The predicted heat flow behavior may be useful in selecting proper housing materials.

We used a one-dimensional monolithic catalyst model to predict the transient thermal and conversion characteristics of a dual monolithic catalytic converter with a Palladium only (Pd-only) catalyst and a Palladium/Rhodium (Pd/Rh) catalyst. Prior to the numerical investigation of the dual-catalyst converter, we modified the pre-exponential factor and activation energy of each reaction for both catalysts to achieve acceptable agreement with experimental data under typical operating conditions of automobile applications. We validated the conversion behavior of the lumped parameter model for each catalyst against different engine operating conditions. Two higher cell density substrates, Pd-only catalyst (600cpsi/3.9mil) and Pd/Rh catalyst (600cpsi/4mil), for faster light-off and improved warm-up performance are used in this study and the two monoliths has been connected without the space between monoliths.

The engine indicated torque is not delivered entirely to the wheels, because it is lowered by losses, such as the pumping, mechanical friction and front auxiliary power consumption. The front auxiliary belt drive system is a big power consumer-fueling and operating the various accessory devices, such as air conditioning compressor, electric alternator, and power steering pump. The standard fuel economy test does not consider the auxiliary driving torque when it is activated during the actual driving condition and it is considered a five-cycle correction factor only. Therefore, research on improving the front end auxiliary drive (FEAD) system is still relevant in the immediate future, particularly regarding the air conditioning compressor and the electric alternator. An exertion to minimize the auxiliary loss is much smaller than the sustained effort required to reduce engine friction loss.

A preliminary study was conducted to develop an automotive thermal energy storage unit for reduction in emissions and for increase in occupants comfort in winter. To prevent thermal storage performance degradation of the thermal storage media some additives were mixed with the base material Bariumhydroxide-octahydrated(Ba(OH)2·8H2O), and offers promising degradation-resist characteristics. The thermal energy storage unit was then optimally designed based on parameter study and empirical analysis. A comparison was made with a commercially available heat battery. Peak power of the developed thermal energy storage unit was about three times higher than that of the existing one.

This paper describes real-time hardware-in-the-loop simulator using the RT-Lab, Simulink and Bikesim to simulate an each major part of electric bike system in real time. The major components of electric powered bike system consist of a PMSM fed by a 3 phase MOSFET inverter, battery and main controller. SimPowerSystem that is one of the toolbox of the Matlab/Simulink is used for modeling and simulation of power components. Each major electric component of the electric powered bike is modeled by Model-Based Design (MBD) method with Simulink. Interworking methods between software such as battery, motor/inverter, bike dynamics model and hardware such as battery, motor/inverter, power supply, electric loader are also described for real-time hardware-inthe- loop simulation based on RT-Lab and Simulink. Especially, this paper describes how to assess the performance of each component with rest of the electric parts in real time.

Recently, there has been increasing interest about vehicle active safety systems to prevent accidents which are caused by adverse weather conditions or inattention of drivers. Especially, ACC (Adaptive Cruise Control) systems using radar sensors are the most widespread.[1,2,3] But it has not been clearly suggested how to test the automotive radar which is applied on the vehicle. In addition, it can be tested on limited place like a laboratory for short distance and it cannot be tested for long distance over 50m. Performance evaluation method is verified by comparing the difference of distances between base vehicle (which the radar sensor is mounted) and target vehicle measured by the precise positioning technology and the radar sensor. It is also possible to test ACC system on a driving road over 50m. In this paper, the precise positioning technology using the VRS and INS is proposed and verified.

An on-board monitoring system for an automobile emission gas has developed using porous ceramic sensor to apply in automotive. We have performed model experiment using similarity and engine dynamometer experiment. By the model experiment, output signal of HC sensor is followed with amount of hydrocarbon in the mixed gas under high temperature range. A single hydrocarbon sensor exposed to the exhaust gas in the chamber to render a signal responsive to the hydrocarbon. The HC sensor in test chamber checked the conductive ions in emission gas. A preferred application includes hydrocarbons in an automotive exhaust gas stream by exposing a porous alumina (Al2O3) ceramic based sensor to the same exhaust gas stream. By combining the electrical signal, a measure of hydrocarbons can be provided. By the developed temperature mode test and the load mode test for engine dynamometer experiment, we have confirmed a possibility of catalyst monitoring used HC sensor in the engine dynamometer.

On-board diagnostics (OBD) of diesel vehicles require various sensors to detect system malfunctions. The Particulate Matter (PM) sensor is one of OBD devices which gather information which could be critical in determining a crack in the diesel particulate filters (DPFs). The PM sensor detects PM which penetrates cracked DPFs and converts the amount of PM into electrical values. The PM sensor control unit (SCU) receives those analog signals and converts them to digital values through hardware and software solutions. A capacitive sensing method would be a stable solution because it detects not raw analog signals but electrical charges or a time constant going through the capacitive load. Therefore, amount of PM would be converted reasonable value of capacitance even though there is a little amount of PM.