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The sense of a human being is expressed in a word always with the sensuous evaluation to idling noise. However, due to the sense of the human being is very complicated basically and be including delicate elements, there is a limit to express it in a word. Also, idling noise might be giving a stress to our body, without feeling it. Then, several studies have been made on physiological information receive the response of a human being objectively, tried to evaluate the load of a body. Electrocardiogram (ECG) and respiratory curve were measured to examine the influence that the disclosure of idling noise exerts on the autonomic nervous system function in this study. Heart rate variability (HRV) was obtained from ECG and respiratory frequency was obtained from respiratory curve in the analysis. Seven subjects were adult males who were healthy hearing. We investigated the result with considering the differences by 4 kinds of noise and 2 kinds of sound pressure.

The influence of the head shape on intracranial responses under impact was investigated by using Finite Element Method. Head shape models of 52 young adult male Japanese were analyzed by Multi Dimensional Scaling (MDS), and a 2 dimensional distribution map of head shapes was obtained. Five finite element models of the Japanese head were constructed by a transformed finite element model of an average European adult male (H-Head model) using Free Form Deformation (FFD) technique. The constructed models represent the 5th and 95th percentile of the first 2 scales obtained by MDS. The same acceleration pulse was applied to the H-Head model and the five finite element models. The cause of the difference was considered to be differences in pressure distribution in the brain caused by the differences in the head shape. Variation in the head shape should be taken into account in simulating the effects of impact using a finite element model.

The Real Driving Emissions (RDE) test method has been introduced after 2017 to regulate the vehicle emissions in real-world driving situations by means of on-board emissions measurements. This paper aims to estimate the detailed on-board gaseous emissions from a light-duty direct-injection gasoline vehicle simultaneously using both portable emissions measurement system (PEMS) and sensor-based emissions measurement system (SEMS). Test route is typical urban route and tests environment factors followed the RDE regulation. Carbon dioxide (CO2), carbon monoxide (CO), nitrogen oxides (NOx), and ammonia (NH3) emissions were analyzed according to cold start once and followed by hot start conditions. The mass emissions of gas components were calculated based on the exhaust flowrate obtained from OBD parameters, NH3 emission was calculated based on NO sensor’s data. Two drivers participated in the tests and their emissions difference has been compared.

The aim of this study was to build a model-based design tool that allows multidisciplinary teams to design vehicle performance targets using an easily understandable common index during the conceptual design phase of vehicle ride comfort performance. The newer a system is in the conceptual design stage without a prototype, the more difficult it is to describe its performance and impact on the vehicle. The originality of this study lies in the proposal of an understandable design tool for the social implementation of new technology, referred to as the multidisciplinary optimization (MDO) and “1DCAE” design concept. More specifically, the subject is the conceptual design of a unique electronically controlled damper system. A model-based development tool was developed, and numerical analysis was performed based on the following approach.

Three-way catalysts are used in gasoline vehicles for simultaneous purifying nitrogen oxide, carbon monoxide, and hydrocarbon in recent years. However, the reduction of ammonia emission generated in the three-way catalyst is pressing issue. In EURO 7, ammonia will also be subject to the Real Driving Emissions regulation, and its emissions must be reduced. Previous studies have shown that ammonia emissions are higher under fuel-rich conditions, suggesting that differences in driving behavior have a significant impact on ammonia emissions in real-world driving, which includes various driving environments. In this study, driving tests were conducted on a direct- injection gasoline vehicle equipped with a three-way catalyst and Portable Emission Measurement System and Sensor-based Emission Measurement System to investigate the actual ammonia emissions on actual roads.

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.