• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2010년도 추계학술대회 논문집
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• pp.599-606
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• 2010

This paper presents dynamic analysis of FCEV (Fuel Cell Electric Vehicle) Turbo Blower. To analyze the dynamic characteristics of Turbo Blower, finite element model which consists of solid elements is constructed. Evaluation of stress for safety of rotor sleeve due to centrifugal force, Shrink fit analysis in maximum rotation speed is performed. Rotor dynamic analysis of Turbo blower is conducted using Campbell diagram and FEA (Finite element analysis) results are compared with experimental results to evaluate of validity of finite element model. To evaluate of Structure vibration characteristics, Modal analysis and forced vibration analysis are performed through FEA and experiment.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2007년도 추계학술대회논문집
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• pp.626-629
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• 2007

Vibration originated from the fuel pump is transmitted to the fuel pump module and fuel tank. Fuel tank transmits it to chassis of vehicle. Also, noise perturbed through fuel and fuel tank is radiated out. Dynamic characteristics of fuel tank are composed of tank structure and containing fuel quantity. Therefore, this study is focused at fuel tank with various quantity. As a result, characteristics of vibration for various fuel quantity in a tank are identified as the more mass of fuel is, the less the 1st resonance frequency decrease. Also, between acoustic camera and mode shape of modal analysis are used for searching the positions of radiated noise and are found to be in accordance with each other.

• 한국산학기술학회논문지
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• 제21권11호
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• pp.617-623
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• 2020

다수의 승객을 운송하는 도시철도 전동차는 도시 철도교통시스템의 핵심이다. 따라서 차량의 동적성능이 확보가 차량 안전 확보 및 승객서비스 차원에서 선행되어야 한다. 철도차량의 진동, 승차감과 같은 동적거동은 현가시스템 구조 및 현가요소에 따라 크게 영향을 받는다. 철도차량의 현가시스템은 윤축과 대차간 1차현가시스템, 대차와 차체간 2차현가시스템으로 구성되어 있다. 본 논문에서는 국내에서 운용되고 있는 전동차 현가구조에 따른 전동차의 동적거동에 대하여 분석하고자 한다. 현가구조가 상이한 2종류의 전동차에 대하여 실제 선로에서 동일 주행조건으로 주행시험을 수행하였으며 차량의 진동을 계측하였고 진동과 승차감, 진동감쇠율과 같은 동적거동 특성을 분석하였다. 시험결과, 차체 진동성능은 좌우방향은 B대차가, 상하방향은 A대차가 상대적으로 우수하게 나타났다. 승차감은 전반적으로 A대차가 B대차에 비하여 우수하게 나타났다. 진동감쇠율을 보면, 1차현가시스템은 고무스프링이 적용된 A대차에 비하여 코일스프링이 적용된 B대차의 진동감쇠 성능이 우수하며 2차현가시스템은 코일스프링에 비하여 공기스프링이 적용된 A대차의 진동감쇠 성능이 우수하다. 본 논문의 결과는 향후 철도차량 신차 설계 과정에서 현가구조 설계 및 현가요소 선정 시, 유용한 자료로 활용될 것이라 기대된다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 1993년도 학술발표집 지반진동 영향평가
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• pp.73-82
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• 1993

Ground-borne vibration is one of the main causes of environmental impact from subway systems. The vibration resulting from track-train interaction is transuutted through the tunnel structure and the surrounding ground to adjacent buildings. This paper provides a summary of proposed noise and vibration criteria, a review of the ground vibration propagation mechanism and the theoretical isolation effectivenesss of each of the following underground transit systems : track, tunnel and vehicle itself.

• 한국군사과학기술학회지
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• 제4권1호
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• pp.13-19
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• 2001

It is known that displacements, velocities and accelerations of the tractor- trailer type vehicle system in shock & vibration analysis by the flexible-multi-body dynamics including the flexibility of structure are bigger and more repetitive than them by the rigid-multi-body dynamics, and it is necessary to prove above results by the experimental field test. Therefore, in this paper, theoretical analysis by the flexible-multi-body dynamics and experimental field test for a tractor-trailer type vehicle system are conducted and their results are compared with each other. Because of unexpected metal contact and impact in the air coupler part in the field test, some accelerations measured from the experimental field test are bigger than them analyzed from the theoretical analysis, but most accelerations are well coincide with each other in the amplitudes and trends. Thus more refined dynamic analytical models for some special type vehicle systems will be possible in the future.

• 한국소음진동공학회논문집
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• 제21권10호
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• pp.951-959
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• 2011

In this study, an OTM(on-the-move) antenna which is mounted on ground vehicles and is used for mobile communication between vehicle and satellite while moving was addressed. Since LOS(line-of-sight) of antenna should direct satellite consistently while vehicle moving to guarantee high satellite communication quality, active antenna LOS stabilization is a core technology for OTM antenna. Stabilization of a satellite tracking antenna which consists of 2-DOF gimbals, an elevation gimbal over an azimuth gimbal, was considered in this study. In consideration of driving mechanism which consists of gear train and flexible driving shafts, a two-mass-system dynamic model coupled with vehicle motion was presented. An internal PI-control loop + outer PI-control loop structure has been suggested in order to damp the torsional vibration and stabilize control system. The classical pole-placement method was applied to design control gains. In addition, a vehicle motion compensation control beside of the feedback control loop has been suggested to improve LOS stabilization performances. The feasibility of the proposed control design was verified along with some experimental results.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2013년도 추계학술대회 논문집
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• pp.94-98
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• 2013

Transfer Path Analysis (TPA) is commonly used, by car makers and parts suppliers, analysis process to root the cause of NVH problems. In general, TPA is an analyzing technique to find the contributing factors of noise/vibration problems, and their transfer path in vehicle. However, not only TPA is used to analyze the source of NVH problems but also is used to predict NVH performance prior to the proto vehicle, or to set the development target for next new vehicle. Automotive parts manufacturing companies have to set NVH performance target when developing new systems just as car makers have NVH target set for new vehicle. Nevertheless, most of components are currently being developed based on subjective evaluation without an objective target. To judge the suitability of using TPA to set NVH target of electric parking brake, this research analyzed the transfer path by setting them in two points of view; Chassis Module and Electric Parking Brake, and comparing the measured value and calculated value. From this result, NVH target of electric parking brake will be approached in level of vehicle, system and component.

• Structural Engineering and Mechanics
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• 제20권1호
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• pp.111-121
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• 2005

The dynamic interaction of vehicle-bridge is studied by using transfer matrix method in this paper. The vehicle model is simplified as a spring-damping-mass system. By adopting the idea of Newmark-${\beta}$ method, the partial differential equation of structure vibration is transformed into a differential equation irrelevant to time. Then, this differential equation is solved by transfer matrix method. The prospective application of this method in real engineering is finally demonstrated by several examples.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2007년도 춘계학술대회논문집
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• pp.220-223
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• 2007

Acoustic test of the payload fairing of Korea satellite launch vehicle was conducted to verify the performance of acoustic protection system installed inside the payload fairing. This paper briefly introduces the acoustic test procedures and its results. Overall 148 dB acoustic loads were exerted on the payload fairing structures which mated with the upper stage structure of the launch vehicle. In order to verify the increase of insertion loss by the acoustic protection system, two kinds of test were performed. One is conducted with acoustic protection system and the other without acoustic protection system. Internal acoustic loads as well as external ones were measured and the measured insertion losses were compared with the requirement. The results showed that the acoustic protection system increases the insertion loss by more than 6 dB above 125 Hz. They also indicated that some design modification of Helmholtz resonator array is required to increase the insertion loss at a cavity resonant frequency.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2001년도 춘계학술대회논문집
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• pp.1221-1226
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• 2001

A structure gauge assessment is needed to ensure that a railway vehicle can run safely along a length of track without coming unacceptably close to lineside structures or equipment, or to vehicles running on adjacent tracks. This apparently straightforward question is in reality very complicated. The amount of space required for the safe passage of a railway vehicle is significantly greater than its static body profile for a number of reasons as follows: as the vehicle runs along the track, the track input excites the vehicle and it moves on its suspension. On curved track its geometric position leads to curve overthrows. A number of different approaches have been used to answer this question and some are described and specially applied to urban train by computer simulation in this paper. The program used for calculating the kinematic and swept envelope is the VAMPIRE made in U.K.