• Journal of Advanced Marine Engineering and Technology
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• 제19권4호
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• pp.61-71
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• 1995

Nowadays the thin-walled metal bearing, which is made seperately from the bearing housing and has the ratio of wall thickness/bearing diameter being less than 1/30, are used in many newly developed large-sized slow speed diesel engines for the purpose of upgarding lubication performance and easy maintenance according to the trends of increasing output per cylinder and lowering engine speed. The type of this bearing has been used generally in many small-sized high speed engines applied for automobile, high speed craft and industrial power generation systems since 1950s. But the tranditional thick-walled bearings, whice are linned white metal on the bearing housing directly, have been installed on the large and slow speed engines until 1990s due to the easy manufacturing procedures. In this study we have calculated optimum dimensions of the metal bearing, fabricated special zigs for crush measurement, model test machine, 2 sets of specimens.(crosshead pin bearing, $\phi$818*552*20mm) for B & W 6S70MC(20, 940*88rpm), and evaluated metal constact phenomena of white metal, its friction coefficient, temparature rise through the model test and field performance test.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2014년도 춘계 학술논문 발표대회
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• pp.188-189
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• 2014

Recently, structural system of apartment building is changing from wall type to column type to accommodate various life styles of residents in Korea. Reinforced-concrete bearing wall structures have been mainly used in apartment construction since 1980's. It is impossible to remove the bearing wall in case of remodeling a house, so that the lightweight wall is needed to apply to the column type structure of the Long Life Housing. Therefore, the purpose of this study is to evaluate the construction performance of the wall. Constructibility reviews are performed throughout interview survey from builders who charge with managing the construction of the lightweight wall in field. This paper present that constructor prefer the bearing wall rather than the lightweight wall because of the schedule delay, difficulty of management, and lack of skilled labor. The results indicate what we should improve on the lightweight wall from now on.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 1996년도 International Conference on Agricultural Machinery Engineering Proceedings
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• pp.354-358
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• 1996

At design stage of the TRXI agricultural tractor transmission (New product of TongYang Moolsan Co., Ltd), the noise and vibration of the transmission were analyzed theoretically for the optimal design of the transmission . For this analysis, the finite element model was developed using a commercial computer software, ANSYS. The noise and vibration of the TRXI transmission housing were predicted by the modal analysis. Natural frequency of the TRXI transmission housing was ranged from 12.53Hz(1st mode ) to 30.05Hz(5th mode). The fifth mode took place at the bearing metal in the area of rear transmission housing and was very close to the gear mesh frequency (30.5Hz) of low rang gear at the low creep shifting . Based on the results , the bearing metal of the range shift housing was reenforced with the rib at design stage.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2004년도 추계학술대회논문집
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• pp.199-203
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• 2004

In this paper, a simplified model is studied to predict analytically the radiated noise from the helical gear system due to an axial excitation of helical gear. The simplified model describes gear, shaft, bearing, and housing. To obtain the axial force of helical gear, mesh stiffness is calculated in the load deflection relation. The axial force is obtained from the solution of the equation of motion, using the mesh stiffness. It is used as a longitudinal excitation of the shaft, which in turn drives the gear housing through the bearing. In this study, the shaft is modeled as a rod, while the bearing is modeled as a parallel spring and damper only supporting longitudinal forces. The gear housing is modeled as a clamped circular plate with viscous damping. For the modeling of this system, transfer function from the shaft to the clamped plate are used, using a spectral method with four pole parameters. Out-of-plane displacement for the thin circular plate with viscous damping is derived and sound pressure radiated from the plate is also derived. Using the model, parameter studies are carried out.

• 토지주택연구
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• 제2권1호
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• pp.79-85
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• 2011

지반의 지지력은 안정화, 다짐공법등 고전적인 지반개량공법에 의한 증대된다. 최근, 지지력을 향상시키기 위한 내구성이 있고 강성이 큰 토목섬유의 유용성때문에 지오텍스타일의 사용은 보편화되고 있다. 본 논문에서는 모래지반에 보강재를 수평으로 등간격 배치하여, 평면 변형률 상태의 실내모형실험을 실시하고 지지력의 개량효과와 거동을 분석하였다.

• Journal of the Korean Wood Science and Technology
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• 제41권2호
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• pp.100-104
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• 2013

Bearing occurs by the rotations of members induced from horizontal or vertical load at traditional wooden joint in frame. The bearing between wooden members is not occurring at the whole surface of joint, but occurring only at the particular bearing area. In this study, partial bearing according to the different grain direction was evaluated. The partial compressive strength showed 3 times higher than pure compressive strength perpendicular to grain, 1.5 times higher than parallel to grain and 3.3 times higher than both of them. It is expected that this result can be very importantly applied when evaluating and analyzing the actual behavior of traditional wooden mortise and tenon joint.

• Journal of Mechanical Science and Technology
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• 제16권11호
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• pp.1395-1403
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• 2002

The characteristics of gear meshing vibration undesgo change as the vibration is transmitted from the gear to the housing. Therefore, vibration transmission characteristics of helical gear systems must be understood before the effective methods of reducing gear noise can be found. In this work, using a helical gear with different lead errors, the gear vibration in the rotational direction and the bearing vibration are measured. The frequency characteristics of gear and bearing vibration are investigated and a comparson is also provided.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2006년도 추계학술대회논문집
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• pp.239-243
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• 2006

A noise/vibration of the forklift happens in the driving axle to charge the drive and are examined closely by an each reason. After this study consider a reduction method of a noise/vibration about the gear, axle, bearing and others, the purpose of this study is to reduce a noise/vibration for a stability of the total system. From the data to be measured through all experimental method, the problems of the gear, axle, bearing, housing and others are examined closely, and the forklift is derived the model to be the engineering. The Mechanism of the problem occurrence is examined through a palametric research about an each influence factor. Lastly, the resuls of this study propose the model to he improved.

• 한국정밀공학회지
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• 제12권2호
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• pp.69-78
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• 1995

Nonlinear analysis methods are developed which will enable the reliable prediction of the dynamic behavior of the space shuttle main engine(SSME) turbopumps in the presence of bearing clearances and other local nonlinearities. A computationally efficient convolution method, based on discretized Duhamel and transition matrix integral formulations, is developed for the transient analysis. In the formulation, the coupling forces due to the onlinearities are treated as external forces acting on the coupled subsystems. Iteration is utilized to determine their magnitudes at each time increament. The method is applied to a nonlinear generic model of the high pressure oxygen turthods, the convolution approach proved to be more accurate and highly more efficient. For determining the nonlinear, steady-state periodic responses, an incremental harmonic balance(IHB) method was also developed. The method was successfully used to determine dominantly harmonic and subharmonic(subsynchronous) responses of the HPOTP generic model with bearing clearances. A reduction method similar to the impedance formulation utilized with linear systems is used to reduce the housing-totor models to their coordinates at the bearing clearances.

• 콘크리트학회논문집
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• 제19권4호
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• pp.507-514
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• 2007

이 논문은 기존 내진설계와 비교하여 면진설계의 효용성과 경제적 효과에 대한 연구 결과를 정리한 것이며, 면진설계에 있어서는 납봉삽입적층고무베어링 (LRB)만을 사용한 경우와 비교하여 슬라이딩베어링과 LRB를 혼용한 면진시스템의 내진 거동을 함께 제시하였다. 연구 결과, 면진은 구조물에 대하여 지진동으로 인한 효과를 감소시키는데 매우 효과적이며, 층 가속도의 감소로 사용성을 증가시킬 수 있음이 입증되었다. 또한 층 가속도와 밑면 전단력의 감소라는 관점에서 슬라이딩베어링과 LRB를 혼용한 면진시스템이 LRB만을 사용한 경우보다 더 효과적임을 증명하였다. 하지만 경제적 효과 면에서는 증가된 성능에 비례하여 지불해야만 하는 비용도 커진다는 사실에 특별히 주의할 필요가 있는 것으로 나타났다.