• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1996년도 봄 학술발표회 논문집
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• pp.225-231
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• 1996

The dense graded asphalt concrete materials have been used for construction of pavement for a long time. The performance of asphalt concrete pavement, however, is influenced by various factors including high temperature and heavy axle loads which cause plastic deformation. The plastic deformation is one of the main functional disadvantages of flexble pavement. In this study, the semi-rigid pavement is considered to solve the problem. A set of experimental evaluation on semi-rigid pavement material has been coducted in laboratory to obtain it's physical properties and serviceabilities. The results of tests, including compressive strength, flexural strength, ravelling and wheel tracking, show that the semi-rigid pavement has a good mechanical properties and serviceabilities. Consequently, the semi-rigid pavement may be suitable to bridge deck, tunnel, slow lane and parking area pavements.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 1996년도 International Conference on Agricultural Machinery Engineering Proceedings
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• pp.404-412
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• 1996

For the cultivation of big agricultral areas high performance machinery is needed. The need to increase working productivity also leads to powerful machinery. The total weight of new tractor generations increases and with it their axle and wheel weight reaches a soil damaging extend. Besides carrying the mass of the tractors and harvesting-machines the chassis must transmit driving force onto the ground(Tab. 1). To decrease soil damaging compaction a number of technical solutions have been developed. Broad tyres are being used to minimize the contact-area pressure by using low tyre air pressure. For enlarging the contact area there are two-possibilities : to build a brought or a long contact area. done for instance in caterpillar tracks.

• International Journal of Railway
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• 제5권2호
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• pp.71-76
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• 2012

Recently, axle load, operating speed and traffic density on railroads have had a tendency to increase and thereby cause additional pressure applied on used track. These operating conditions frequently result in service failure due to wear caused by wheel-rail contact and fatigue damage under cyclic loading. Among rail defects, the transverse crack, which has been the most dangerous type of fatigue damages, is developed from the subsurface crack near the rail running face and grows perpendicular to the rail surface. Therefore, it is necessary to investigate systematically the growth behavior of transverse crack for rail steel under mixed mode. In this study, the fatigue crack growth behavior of the transverse crack in rail steel was experimentally investigated under mixed-mode variable amplitude loadings.

• 한국소음진동공학회논문집
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• 제24권8호
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• pp.592-599
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• 2014

A torsional vibration at driveline happens seriously at rapid vehicle acceleration. The torsional vibration at driveline can be reduced by optimization of joint angle and yoke phase angle of driveline. But, the joint angle of driveline is changed according to vehicle driving condition as acceleration, deceleration, forward and backward driving, so that excessive vibration is transmitted to vehicle body at specific driving condition. Especially under rapid acceleration condition, vibration transmitted to body could be maximized because excitation force at rapid acceleration is bigger than that at normal driving condition due to changed joint angle. The torsional vibration of driveline can be kept at low level by controlling suspension parameter to minimize rigid axle displacement as well as optimizing joint angles considering the vehicle acceleration condition.

• 한국철도학회논문집
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• 제2권2호
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• pp.13-20
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• 1999

The vibration signals of driving parts of electric train are distorted its signal patterns due to the impact components, which occurs when wheel passes rail joints. An elimination method of the impact components is investigated using adaptive signal processing technique in this study The result shows that adaptive interference canceling method seems to be more effective than line enhancement technique. The application of adaptive interference canceling method to the signal measured at bogie shows that the extractions of the signals of driving parts of traction motor, reduction gear, and axle bearing are successful. Therefore, only the signals of bogie, which is the place to attach an accelerometer easily, is sufficient for the fault diagnosis and the safety evaluation of electric train. Also, adaptive interference canceling method can be applicable to evaluate the performance of vibration isolation between bogie and car body and to investigate the characteristics of indoor sound.

• 대한기계학회논문집A
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• 제33권11호
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• pp.1320-1325
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• 2009

The sources of the vibration of railway vehicles in the cabin are usually bogie, axle, and wheel. The vibrations are transmitted through the floor structures of railway vehicle. The floor structure is the combination of bottom plate, plywood, and rubber. In this research the vibration transmission is measured experimentally and analyzed numerically to find the transmission characteristics of the vehicle floor structures. The result shows that the vibration characteristic of soft rubber is better than hard rubber or wood as the connecting material between the bottom plate and the plywood.

• 한국철도학회:학술대회논문집
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• 한국철도학회 1999년도 춘계학술대회 논문집
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• pp.143-150
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• 1999

The vibration signals of driving parts of electric train are distorted its signal patterns due to the impact components, which occurs when wheel passes rail joints. An elimination method of the impact components is investigated using adaptive signal processing technique in this study. The result shows that adaptive interference canceling method seems to be more effective than line enhancement technique. The application of adaptive interference canceling method to the signal measured at bogie shows that the extractions of the signals of driving parts of traction motor, reduction gear, and axle bearing are successful. Therefore, only the signals of bogie, which is the place to attach an accelerometer easily, is sufficient for the fault diagnosis and the safety evaluation of electric train. Also, adaptive interference canceling method can be applicable to evaluate the performance of vibration isolation between bogie and car body and to investigate the characteristics of indoor sound.

• 한국철도학회:학술대회논문집
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• 한국철도학회 1999년도 춘계학술대회 논문집
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• pp.135-142
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• 1999

This paper deals with dynamic characteristics of automated guideway transit vehicle with rubber tires. Several models for guideway system of LRT(Light Rail Transit) have been Proposed because of the necessity of guideway system for LRT with rubber tires on exclusive rail unlike steel tires. Here, steering system and bogie system are investigated to compare with dynamic characteristics. On selecting guideway system, the way of vehicle operation should be considered and simultaneously the dynamic characteristics of the vehicle must be evaluated with respect to each guideway. The results show that stability is essential for vehicle with steering system, and that single-axle bogie system gives the good stability, though it is necessary to reduce the guide-wheel force

• 한국철도학회:학술대회논문집
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• 한국철도학회 2001년도 춘계학술대회 논문집
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• pp.295-302
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• 2001

The lateral stability of curved continuous welded rail (CWR) is studied fur buckling prevention. This study includes the influences of vehicle induced loads on the thermal buckling behavior of straight and curved CWR tracks. quasi-static loads model is assumed to determine the uplift region, which occurs due to the vertical track deformation induced by wheel loads of vehicle. Parametric numerical analyses are performed to calculate the upper and lower critical buckling temperatures of CWR tracks. The parameters include track lateral resistance, track curvature, longitudinal stiffness, tie-ballast friction coefficient, axle load, truck center spacing, and the ratio of lateral to vertical vehicle load. This study provides a guideline for the improvement or stability for dynamic buckling in on tracks.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2004년도 추계학술대회 논문집
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• pp.1357-1360
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• 2004

In this paper, a prototype of agent-based engineering system is developed based on the AADE (autonomous agent development environment), a FIPA compliant agent platform. By applying several advanced technologies including software agents, Internet/Web, workflow and database, the developed prototype system is able to successfully fulfill our target of integrating personnel, design activities and engineering resources along a predefined engineering design project (workflow). A software prototype is implemented to integrate various engineering software tools including CAD, structural analysis (FEA), dynamic analysis, fatigue analysis. A wheel-axle-assembly (part of a bogie system) is chosen as a test case for the validation of the prototype system.