• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2004.11a
• /
• pp.546-549
• /
• 2004

The T-50/A-50 Golden Eagle was developed for a supersonic trainer and light combat aircraft. At the design stage, vibration control plans were established and applied. For cockpit vibration, crew comfort vibration level was defined by the requirement of MIL-A-8892. It is found that the T-50/A-50 meets the requirement of cockpit vibration from the flight test data analysis. This paper contains the results of cockpit vibration analysis using the flight test data and the results of human vibration analysis lot the pilot inside aircraft. The human vibration level of pilot is increased as dynamic pressure is increased and at the specific high dynamic pressure, the ride comfort indicates 'a little uncomfortable'. Overall analysis results show that the vibration level of T-50/A-50 cockpit is tolerable and not critical for pilot's comfort.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.21 no.1
• /
• pp.193-208
• /
• 2022

The purpose of this study is to verify how the EV rent-a-car satisfaction affect the purchase intention of the EV. As a result of the study, Gender, Age, Quietness & Ride comfort, Charging infrastructure had a significant correlation with the EV rent-a car satisfaction level. and It is confirmed that the factors of Age, Quietness & Ride comfort, Charging infrastructure affect the EV purchase intention of the EV through the EV rent-a-car satisfaction level. The differentiation of the study is that it was analyzed through empirical research, focusing on the EV rent-a-cars as a major means of spreading the EV. also the analysis target was limited to first-time the EV's Users through the EV rent-a-car.

• Proceedings of the KSR Conference
• /
• 2007.05a
• /
• pp.169-174
• /
• 2007

Adopting articulated bogie system, the HSR350x and KTX have similar physical mechanical characteristic, but they show different dynamic characteristics due to different position of suspensions and those physical properties. The low level vibration frequency which effects on the ride comfort of passengers and the high level vibration frequency which is related to noise of vehicle have been measured by accelerometers mounted on Wheel sets, Bogies and Car bodies to analysis the dynamic characteristics of the High-Speed Trains. The KTX number 36 is utilized to measure the lateral and vertical acceleration value of car body, and total measurement system of HSR350x have been used to acquire acceleration data. The sampling frequency of data is 500Hz generally, but the Car body at TT2 of HSR350 has 1000Hz exceptionally.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.6 no.4
• /
• pp.151-159
• /
• 1998

The heavy equipment such as tracter has been studied to improve rather the performance of engine than comfort. The mufflers of tracters have various specifications according to their uses. The exact analysis of various mufflers is needed to reduce the level of exhaust moise, a major noise source of engine, to improve the ride quality of tracter. In this study, a software based on Green's function is developed to predict the performance of sound transmission loss for a muffler according to the locations of inlet/outlet pipes. The locations of inlet and outlet pipes can be fixed at different position individually. The conventional muffler has the locations of inlet/outlet pipes on the direction of longitudinal axes. On other hand, the inlet and outlet pipes may be located at the circumferential surface of a test muffler such as one of tracter. The software is verified by analysis and experiment on current muffler of tracter and the improvement technique is proposed to reduce the level of exhaust noise.

• Proceedings of the KSR Conference
• /
• 2008.11b
• /
• pp.1413-1419
• /
• 2008

As the improvements of service quality is becoming an important issue the, interior noise level of a train is an important factor of comfortable ride. To reduce the interior noise level, noise sources of the train need to be removed. However, in case with a structure of large scale and multiple noise sources, an estimation of influences of major noise sources, with indentification of its traveling paths needs to be performed. In current state, to improve the interior noise reduction, consideration of sound transmission loss of the train body prior to manufacturing is usually performed. In this study, the sound transmission loss of the train body of new model train of seoul metro's line no.2 under test opeation is measured and modeling of the train body is performed. And train interior noise is predicted using the measured values.

• Proceeding of EDISON Challenge
• /
• 2016.03a
• /
• pp.246-255
• /
• 2016

When spring of the suspension is exerted by an external load, a car should be designed to prevent predictable damages and designed for a ride comfort. We used experiments design to design VON-MISES STRESS and K, a constant, of spring of suspension which is installed in a car as a goal level. We analyzed the result from Edison's Elastic - Plastic Analysis SW(CSD_EPLAST) by setting D, d, n as external diameter of coil, internal diameter of coil, the number of total coil respectively. The experiment design let the outcome be as Full-second order by using Box-Behnken which is one of response surface methods. Experimented and analyzed results based on the established experiments design, We found out design parameter which has desired VON-MISES STRESS and the constant K. Additionally, we predicted life time of when the external load was exerted by repeated load by using fatigue equation, and verification of plastic deformation has also been made. Additionally we interpreted a model, which is formed by optimized design parameter, with linear analysis and non-linear analysis, at the same time we also analyzed plastic deformation with the values from the both models. Finally, we predicted fatigue life of optimized model by using fatigue estimation theory and also evaluated a ride comfort with oscillation analysis.

• Proceedings of the KSR Conference
• /
• 2011.10a
• /
• pp.2585-2593
• /
• 2011

Maglev train system has been continuously received attention as it provides good ride quality and low noise and vibration level. Furthermore it is an eco-friendly transport system with little dust pollutant. However the dynamic performance of the vehicle has been influenced by the track layout and the structural stability of guideways and girders, etc. Especially the levitation control of magnetic module is the most important performance of the Maglev system and is very sensitive about the control algorithm and the parameters of the controller. In this paper, the co-simulation of the control and dynamic model has been proposed and the simulation results for the running simulation on the curve track has been shown.

• Journal of KSNVE
• /
• v.11 no.1
• /
• pp.76-81
• /
• 2001

This paper addresses experimental results carried out to investigate the transmission of seat vibration to the head for Korean. Vertical seat vibration in the frequency range of 0.5-30 Hz was applied to a seated Korean male subject. To examine the intra-variable effects on transmissibility, five different postures and three different vibration excitation levels were considered. The applied acceleration and head accelerations of the seated subject were measured simultaneously by using a 6-axes bite-bar. Detailed experimental results of measured transmissibilities are illustrated for each posture and/or vibration excitation level, and they were compared to an International Standard. They are found to allow the identification of dynamic characteristics of Korean seated body for various reat vibration environments. Furthermore, they are expected to be very useful in designing new seats for automotive and railway vehicles and in improving their vibration ride quality.

• Proceedings of the KIPE Conference
• /
• 2011.07a
• /
• pp.292-293
• /
• 2011

일반적으로 인버터는 입력 전원에 정전이 발생하였을 때 수 ms 안에 PWM 출력을 차단한다. 부하의 관성이 큰 경우 전원이 복구되었을 때 부하를 가속하는데 긴시간이 필요하게 된다. 이러한 동작은 산업 현장에서 큰 손실로 이어질 수 있고, 따라서 출력을 차단하지 않고 연속운전 할 수 있는 Ride Through 모드를 자사 고압 인버터에 적용하였으며 실제 공정상의 실험으로 이를 검증 하였다.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.11 no.3
• /
• pp.192-197
• /
• 2003

The ‘AEIPR’(Accelerometer Established Inertial Profiling Reference) method has been applied to measure the road profile. The dynamic road profiling method using AEIPR has the advantages of cost effectiveness, measuring speed and relatively high reliability. However, it is required to improve the double integration algorithm to get the measurement results with the accuracy of hither level. In the first part of this paper, the effective double integration algorithm is suggested and the ‘Road Profiler’ software is developed on the basis of the algorithm. Road profiling tests are performed using the developed ‘Road Profiler’ system on the specially designed tracks for the durability tests and the various types of pubic roads. Test results are shown and evaluated by the international road evaluation indicies and classification.