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An efficient approach to classify time series physical measurement data of shift control of automatic transmission for vehicles is presented. Comfortable acceleration is the essential factor of today’s vehicles. Shift control of automatic transmission of vehicles directly contributes to the comfortable acceleration. Since calibration of automatic transmission of vehicles is time consuming task for expert engineers, the development of autonomous calibration is desired to reduce product development period in today’s competitive automobile market. In the stage of product development, it is difficult to obtain a large amount of physical measurement data. Therefore, we need to develop machine learning method for limited amount of data. For this purpose, we develop the method to classify time series measurement data of shift control of automatic transmission of vehicles. We use support vector machine (SVM) as a machine learning technique.

Measurement of the sound intensity vector distribution is a useful way to identify noise sources in a vehicle especially at low frequencies. Due to the effect of standing waves, it is difficult to identify the source location from the sound pressure measurement at the driver's ear position. Direct measurements, such as scanning the entire vehicle cabin with a three-dimensional sound intensity probe is very time consuming, and is not able to track temporal and spatial changes in the sources. In this paper, an approach is presented that provides a prediction of the vector sound intensity field throughout a volume exterior to a rigid spherical measurement array consisting of flush mounted microphones.

This paper describes the porous materials FE modeling scheme inside vehicle cabin using measured acoustic impedances to reduce the size of the matrices of the FE model while keeping the accuracy. The technique of measuring acoustic impedance using PU probe in a free field is introduced. Next, the surface acoustic impedance of the seat by the side of front is measured using this technique. And the vehicle cabin acoustic field is modeled by FEM using the measured surface acoustic impedance. For the accuracy verification of this model, the acoustic transfer characteristics inside vehicle cabin with and without the front seat are compared with the predicted and the measured transfer function. Moreover, finally the worth of this modeling method is considered.

NO, OH, and soot in combustion flame produced from burning at high temperature and pressure diesel fuel spray issuing from a single-hole injection nozzle was measured by laser induced fluorescence (LIF) and laser induced incandescence (LII) methods. The LIF images of OH showed that OH radical, distributed in a band-like zone outside the region of the flame luminescence observed, would persist even after the extinction of flame luminescence. The LIF images of NO showed that NO was located slightly outside the flame luminescence zone and that its region was almost the same as that of OH and would tended to increase in the latter period of the combustion process. Also, the LII images showed that the formation of soot would take place near the flame central zone coincident with the flame luminescence zone.

In this study a new water injection system was applied to an 11 liter naturally aspirated DI diesel engine in order to reduce exhaust emissions. In this system, the water and fuel were arranged in the injection nozzle during the time between injections as fuel, water and then fuel. The fuel and water were then injected into the cylinder in that order. The tests were conducted at several engine operating conditions from the Japanese 13 mode test cycle to clarify effects of water injection on exhaust emissions and fuel consumption. The results showed that NOx reduction was directly proportional to the relative amount of water injection, regardless of engine speed and load. By using the optimal relative amount of water injection at each engine operating condition, total NOx and particulate matter (PM) in the Japanese 13 mode test cycle were reduced by 50% and 25%, respectively, without a fuel consumption penalty.

Recently diesel engines are required to get not only high performance but also low pollution gas quality (oxides of nitrogen, carbon monoxide, unburned hydrocarbons and smoke). Our approach to this requirement is based on the fuel spray theory that good fuel-air mixing in the fuel spray developed into the quiescent air depends upon high kinetic energy of the spray motion. From the theoretical analysis of fuel spray motion in the quiescent air and the photographic study of the fuel spray combustion, it was found that higher rate of air entrainment into the fuel spray by its own kinetic energy gives a very important effect on the increasing of combustion efficiency in the diesel engine and the reduction of soot formation.