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The objective of this study is to introduce and assess a computational tool designed to facilitate product development via sensory scores, which serve as a quantifiable representation of human sensory experiences. In the context of designing ride comfort performance, the specialized terminology—either technical or sensory—often served as a barrier to comprehension among the diverse set of specialists constituting the multidisciplinary team. In a previous study by the authors introduced a tool that incorporated a model of sensory performance, utilizing sensory scores as universally comprehensible metrics. However, the tool had yet to be appraised by a genuine cross-functional team. In this study, the tool underwent evaluation through a user-testing process involving twenty-five cross-functional team members engaged in the conceptual design phase at an automotive manufacturing company.

Energy optimal control theory (EOC) is applied to the energy flow control of a hybrid electric vehicle. Since the differential equation is solved analytically, the control law can be easily implemented in real time. Because the objective function is described in power form that permits negative value, not only the energy consumption is minimized but also the energy regeneration by the motor is maximized. In the simulation for the 10-mode driving, it is shown that the fuel cost of EOC is 15% lower than the rule based control (RBC).

Trapping of diesel particulates and phenomena of chemical reaction in regeneration were investigated by visualization through the cross-sectional area of a diesel-particulate-filter wall, using a digital-microscope with a high focusing depth. Herein, SiC-DPF walls were polished up to make a uniform height and to create a mirror-like surface on each SiC-particle-grain. At the beginning of the trapping process, it was observed that large particulates were trapped once in the small pores inside the wall, and then, since the flow-pattern was changed drastically, the trapped particulates were pushed out and blown off again, and finally, trapped in a region further downstream. As time passed, image analysis disclosed that since fine particulates were deposited around the SiC-particle-grain surface, the flow-channels became increasingly narrow.

In order to investigate early soot formation process in diesel combustion, spectral analysis and optical thermometry of early soot formation region in a transient spray flame under diesel-like conditions (Pg2.8 MPa, Tg620-820K) was attempted via laser-induced fluorescence (LIF) from pyrene (C16H10) doped in the fuel. Pyrene is known to exhibit a temperature\-dependent variation of LIF spectrum; the ratio of S2/S1 fluorescence yields, from the lowest excited singlet state S1 and the second excited singlet state S2, depends on temperature. In the present study, pyrene was doped (1%wt) in a model diesel fuel (0-solvent) and the variation of LIF spectra from the pyrene in the spray flame in a rapid compression machine were examined at different ambient temperatures, ambient oxygen concentrations, measurement positions and timings after start of fuel injection.

In this study, the genetic algorithm so called GA is newly applied for the optimization of many engine mounting parameters, calculations of stiffness matrix and inverse matrix to obtain 6 degrees of freedoms displacements at mounting points and a center of gravity. As a result, the optimized result could be shortly obtained in a minute, and an inexperienced engineer could easily make the optimum engine mounting layout, which can satisfy the vibration isolation and the non-interference in an engine compartment.

Multi-step water splitting with Mn-ferrite(MnFe2O4)/sodium carbonate(Na2CO3) system accompanying endothermic reaction was investigated for converting solar energy into chemical energy. This water splitting is caused by the oxidation-reduction of manganese ion in the Mn-ferrite. Multi-water splitting with MnFe2O4/Na2CO3 system was consisted of three steps. The first step was hydrogen generation at 1073K. The second step was oxygen release at 1273K. The third step was Na2CO3 reproduction at 873K. The mechanism of multi-water splitting has been considered by XRD, chemical analysis of colorimetry and back titration. The temperature range 873 to 1273K is quite lower than those studied on the solar furnace reaction (O2 releasing step) in two-step water splitting (1500-2300K). This lower temperature range would permit further progress in converting the direct solar energy into chemical energy.

The relation between the characteristics of a non-evaporating spray and those of a corresponding frame achieved in a rapid compression machine was investigated experimentally. The fuel injection pressure was changed in a range of 55 to 260 MPa and the other injection parameters such as orifice diameter and injection duration were changed systematically. The characteristics of the non-evaporating spray such as the Sauter mean diameter and the mean excess air ratio of the spray were measured by an image analysis technique. The time required for a pressure rise due to combustion was taken as an index to characterize the flame. It was concluded that the mean excess air ratio of a spray is the major factor which controls the burning rate and that the high injection pressure is effective in shortening the combustion duration and reducing soot formation.