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This research aimed to improve the PN filtration efficiency of a catalyst coated gasoline particulate filter (cGPF) to meet the next generation of emissions regulations for internal combustion engines. This paper proposes a concept that improves the PN filtration performance while maintaining low pressure drop by forming a thin PM trap layer on the surface of the cGPF substrate. The design guidelines for the coating particle size and coating amount of the PM trap layer were investigated, and actual manufacturing issues were also identified. The validity of this concept and guidelines was then verified on an actual vehicle.

An automotive sensor development process is discussed in this paper from the viewpoint of whether it is suitable for achieving new sensors having technological competitiveness. A concrete example of the application of this development process to automotive sensors is presented to demonstrate that it produces technologically competitive sensors. In the first section, a general process is proposed for automotive sensor development. The fundamental concepts underlying this process are summarized below. 1. An analysis of the object to be measured is the starting point for sensor development. This analysis is carried out from four perspectives: (1) the measurement of phenomena for which an electronic system is technologically advantageous; (2) the mechanism of the object to be measured; (3) the characteristic behavior of the object; and (4) the special features of the object. And 2.

A 50 kg/mm2 tensile strength level and an extremely high flangeability were achieved in a developed steel. The steel had a base chemistry of C=0.04%, Mn=0.85%, Nb=0.015%, and S=0.001%, and was processed with a hot rolling finishing temperature of 860 °C and a coiling temperature of 550 °C. This high flangeabilty was attained by reducing S content below 0.002%, as well as reducing carbon content. Elongation results could not be directly correlated to the flangeability of steel. A steel's flangeability has been found to be associated with microvoid distribution in the “as punched” condition. The developed steel exhibited the lowest density, and the smallest size, of microvoid.

With the progress of super computers in recent years, a number of studies on “Computational Fluid Dynamics” (CFD) have been carried out, and various schemes for Navier-Stokes equations have been presented. Similar methods have also been applied to automotive engineering - aerodynamics, for exampre - in order to determine flow phenomena. In this paper, the application of numerical simulations to the flow cavitation that occurs in some part of orifices in the vehicle hydraulic system, will be discussed. Authors have developed a CFD program for the clarification of flow phenomena in such orifices. Using the relationship between calculated results and measured results of noise levels in such orifices, a new method for estimation of the occurrence of flow cavitation has also been developed. As a result, a new orifice configuration capable of preventing the cavitation has been designed.

Numerical analysis by solving the three-dimensional Euler equations has been performed in order to investigate the complicated flow patterns or aerodynamic characteristics of the advanced turboprop (ATP) propeller with two types of spinner configuration. The governing equations are written for a rotating Cartesian coordinate system in terms of absolute flow variables. The solution algorithm used is an implicit approximate factorization method and resultant matrices are efficiently solved by LU-ADI scheme. Moreover, flux vectors are all treated implicitly in order to accelerate convergence. This solver has applied to study the effect of interference between highly swept blades and axisymmetrical spinner on aerodynamic performance of ATP propeller. Numerical results clearly captured overall structures of flow field such as shock formation and clarified that the selection of area-ruled spinner is important for aerodynamic design of an efficient turboprop.

An important factor in the development of vehicle suspensions has been how to get higher performance from both ride and stability, which are normally in conflict. In addressing this problem, we analyzed the optimum damping forces of shock absorbers for various driving conditions and developed an electronically controlled shock absorber system, which we call “Super Sonic Suspension” based on the results. Through this microcomputer-controlled system, we achieved a great improvement in riding comfort by being able to the damping force much lower than before, based on the results of said analysis. At the same time, stability of the vehicle was also improved by optimumly controlling the damping force for various driving conditions through signals from a newly developed road sensor, which utilizes supersonic waves, and other sensors.