• 대한토목학회논문집
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• 제7권2호
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• pp.1-8
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• 1987

최근 지하철 운행의 중대에 따른 지하철 각 부의 진동이 주변지반 및 인접 구조물에 큰 영향을 주고 있다. 본 연구에서는 지하철의 주행으로 인해 발생된 인첩 구조물의 진동을 저감하기 위한 새로운 해석방법을 제안하였다. 즉, X, Y, Z 3 축 방향 성분별로 측정된 각 방향별 기여관계와 각 방향별 진동신호를 하나의 구면파 신호로 합친 진동의 기여관계를 비교 분석하여 효과적인 진동 저감대책의 자료를 제시하였다. 이러한 연구의 결과로 지하철 각 부의 진동이 인근 지역 구조물에 미치는 기여순위는 전동차의 진동(특히, 1~2 Hz), 지하철 박스의 진동, 지반의 진동 순으로 됨을 알 수 있었다.

• 국제물리치료학회지
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• 제11권4호
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• pp.2184-2190
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• 2020

Background: Although studies have been conducted on muscle thickness and balance in trunk stabilization exercise and exercise using vibration props, studies on trunk stabilization exercise using active vibration for spinal alignment are still insufficient to draw a conclusion. Objectives: To investigate the effect of trunk stabilization exercise using active vibration on the spinal alignment in adult females. Design: A randomized controlled trial. Methods: Twenty-six adult females were randomly assigned to the experimental group (active vibration) and 13 control groups (active non-vibrating) and exercised three times a week for 8 weeks. Each group was measured for spinal alignment before exercise and 8 weeks after exercise. Spinal alignment, trunk imbalance, pelvic tilt, and pelvic torsion were measured using a spinal alignment analyzer. Results: Trunk imbalance was a significantly different depending on the time in the experimental group and the control group (P<.05). Pelvic tilt was a significant difference between the groups (P<.05). Also, pelvic tilt was a significantly different depending on the time in the experimental group (P<.05), but the control group showed no significant difference (P>.05). Pelvic torsion was no significant difference in both groups (P>.05). Conclusion: This study demonstrates that trunk stabilization exercise using active vibration has a positive effect on the alignment of the spine.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2000년도 춘계학술대회논문집
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• pp.984-989
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• 2000

This paper deals with an analysis and countermeasure of escalator vibration. The vibration characteristics of escalators are studied theoretically and experimentally to find the main cause of severe vibration. The main source of vibration in escalators is found to be chordal effect due to the step chain and sprocket system. It is also found that the vibration become significantly large at so called no load condition, in which the load due to passengers, during down-moving, is equal to the resistive force in the driving system. Dynamic absorbers are implemented to suppress the vibration. A theoretical analysis is made to determine the appropriate dynamic absorber. Theoretical and experimental study shows that dynamic absorber is effective to suppress the vibration in escalators.

• 소음진동
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• 제7권5호
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• pp.853-860
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• 1997

For this study, the multi-degree of freedom analysis model of torsional vibration was developed. This model is combined with mass moment of inertia and torsional spring in two wheel drive and four wheel drive vehicle. We compared and analyzed torsional vibration characteristics by natural frequencies and mode shapes which are obtained by free vibration analysis of this model. And we studied torsional vibration contribution of driveline elements by performing the forced vibration analysis of engine excitation torque. The validity of this model is demonstrated by the field test. The reduction effect of the torsional vibration along the driveline design factor is presented by the analytical results.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2005년도 추계학술대회논문집
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• pp.251-254
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• 2005

In this study vibration transmissibilities of the selected anti-vibration gloves were measured, and the measurement uncertainty was estimated. Since human factors such as palm size, gripping condition and dynamic properties of the hand-arm effect the measurement a lot, it is necessary to know ow much the uncertainty is. This study takes the measurement procedure suggested in ISO 10819. Three subjects Joined at each test and each anti-vibration glove was tested twice per a subject. Average and standard deviation of vibration transmissibility were calculated and uncertainty of them were estimated at 95% confidence level.

• Journal of Preventive Medicine and Public Health
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• 제27권4호
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• pp.763-776
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• 1994

Recent studies reveal that grip forces during the hand-arm vibration are most significant for the genesis of vibration-induced white linger syndrome. Therefore, exerted grip forces and skin temperatures of fingers were regarded as dependent variables in experiments and the effects of grip temperature, noise, pushing force, vibration and the combined effect of vibration and pushing force were studied. The objectives of the present study were, first, to varify and compare the changes of grip force affected by grip temperature, noise, pushing force, vibration and the combined effect of vibration and pushing force and, second, to observe the reaction of finger skin temperature affected by above factors. Forty-six healthy male students ($25.07{\pm}2.85$) participated in five systematically permuted trials, which endured 4 minutes each other. Experiments were executed in a special chamber with an air temperature of 21C. In each experiments, the subjects were exposed to five experiment types: (1) grip force of 25N only, (2) pushing force of 50N, (3) acceleration of vibration $7.1m/sec^2(z-direction)$, (4) pink noise of 95 dB (A) and (5) combination of pushing force 50N and acceleration of vibration $7.1m/sec^2$. A repeated-measures analysis of variance (ANOVA) was performed on the grip force to test whether it was affected by noise, pushing force, vibration and pushing force. The present results show that vibration was significantly related to the increase of grip force, but the other factors, such as pushing force, noise and grip temperature had no signigicant influence on the increase of grip force, and that the reaction of finger skin temperature were significantly affected by the skin temperature at start of experiment and grip temperature, not grip force and other experimental conditions. Therefore, we suggest that the management for decreasing the grip force is meaningful to prevent the occurrence of Hand-arm vibration syndrome (HAVS).

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2009년도 추계학술대회 논문집
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• pp.508-509
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• 2009

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 1996년도 추계학술대회논문집; 한국과학기술회관, 8 Nov. 1996
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• pp.135-141
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• 1996

Numerical analysis techniques have been applied to obtain the vibroacoustic characteristics of the simplified model of a passenger-car cabin. Two kinds of coupled vibration-acoustic analysis, such as one-way coupling and full coupling, have been carried out via the interface between the results of vibration analysis by FEM and acoustic analysis by BEM. The comparison of two coupled analysis results show the fluid-structure interaction in terms of the coupled effect of the vibration and noise.

• 전산구조공학
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• 제3권4호
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• pp.123-132
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• 1990

일반적으로 구조물의 내진설계에 있어서는 등가정적해석법이 주로 사용되고 있다. 현재 사용되고 있는 등가정적해석법은 구조물의 거동이 주로 기본진동 모드에 의해 지배된다는 가정하에 유도되었으므로 기본진동 주기가 긴 구조물에 대해서는 구조물의 동적특성을 정확하게 예측하기가 어렵다. 본 연구에서는 구조물의 설계시 직접적인 영향을 미치게 되는 층전단력의 분포를 주요 관점으로하여 구조물의 동적특성에 미치는 고차모드의 영향을 정확히 고려할 수 있는 층지진하중에 대하여 연구했다. 층지진하중의 분포를 개선하기 위해 현행 내진설계 기준의 등가정적해석법에서 쓰이는 층지진하중과 모드해석을 이용하여 얻은 층지진하중의 차이를 파악하고 이로부터 고차모드의 영향이 고려된 층지진하중의 분포를 제안했다.

• 한국유체기계학회 논문집
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• 제16권3호
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• pp.5-9
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• 2013

In this study, operational vibration experiment and analysis have been conducted for the 4-blade small vertical-axis wind turbine (VAWT) including the effect of tower elastic behavior. Computational structural dynamics analysis method is applied to obtain Campbell diagram for the VAWT with elastic tower. An open type wind-tunnel is used to change and keep the wind velocity during the ground test. Equivalent elastic tower is used to support the VAWT so that the effect of elastic stiffness of the tower can be considered in the present vibration experiment. Various excitation conditions with wind loads are considered and the dominant operating vibration phenomena are physically investigated in detail.