• The Journal of the Acoustical Society of Korea
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• v.4 no.3
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• pp.21-32
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• 1985

서로 상관관계가 있는 다입력원 진동계의 진동원을 규명하기 위한 방법을 제안하였다. 다차원 스펙트럼 해석을 이용함으로써 지하철 진동의 가장 중요한 진동원을 발견하였다. 이 분석은 진동의 전 달경로가 매우 복잡할 때 다입력-단일출력으로 모델화 하여 분석하는 방법이다. 또한 레지듀 스펙트럼 분석과 부분기여함수의 개념을 적용하여 지하철 진동이 콘크리트 구조물의 진동에 미치는 영향을 마이 크로 컴퓨터로 계산하였다. 이러한 연구의 결과로 지하철 진동의 다차원 스펙트럼의 오버올레벨을 측정 치와 비교하였다.

• Journal of KSNVE
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• v.7 no.2
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• pp.293-300
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• 1997

Noise and vibration induced by subway operation is one of the major problem for the residents living nearby railway tracks. Many scientists and engineers have been working on proposing the more accurate prediction equation of noise and vibration to provide the better residential environment. Some predictiction equations were determined to compare the measurement value of a noise obtained from the inside of a residential area. It was observed that the condition of a soil type is one of the major parameter which should be considered to obtain the more accurate prediction value of a noise.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2001.05a
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• pp.648-655
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• 2001

현재 국내에서는 신항만건설. 경부고속철도 건설, 기존고속도로 신설 및 확장공사 등 대형 국책공사와 도심지 내에서의 아파트부지조성, 고층건물신축, 우회도로, 지하차도, 지하철건설 등 중소형 공사가 증가되고 있으며 이러한 대소형 공사 시에 발생하는 건설소음ㆍ진동은 계획단계에서부터 합리적인 기준설정과 충분한 환경영향평가가 이루어져야겠으며 또한 이러한 평가결과가 공사에 잘 반영되어야 할 것이다. (중략)

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2014.04a
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• pp.139-140
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• 2014

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2001.11b
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• pp.1287-1292
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• 2001

Subway train-induced ground-borne vibration is studied. Previously used vibration level prediction equations are reviewed. Measured vibration levels are compared with the predicted results and numerically computed results. The results show that vibration level does not decrease proportionally with the distance.

• Journal of Life Science
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• v.16 no.7 s.80
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• pp.1174-1180
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• 2006

The present study was sought to clarify whether the combination of mental activity with subway noise affects hematological variables. Fifty-six healthy volunteers participated in this experiment and underwent a stress task consisting of combination_of mental activity (mental arithmetic) with subway noise for 50 min and 60min of recovery after the end of the stress task. Venous blood samples were collected for measuring CBC, prothrombin time (PT), activated partial thromboplastin time (aPTT), erythrocyte sedimentation rate (ESR), fibrinogen concentration, D-dimer and high sensitive C-reactive protein (H-CRP) levels before (baseline), 50min of stress task (S-50m), and 60 min of recovery (R-60m). Total leukocyte, neutrophil and lymphocyte counts significantly increased at R-60m compared with baselines. RBC count at S-50m was higher, while monocyte counts at S-50m and R-60m were lower than those of baselines. aPTTs shortened at S-50m and R-60m, but PT reduced at R-60m as compared with baselines. D-dimer and H-CRP levels at S-50m and R-60m were significantly higher than those of baselines. These findings imply that a combination of mental activity with subway noise nay cause leukocytosis, homo-concentration, shortened PT and aPTT, decreased ESR, and raised D-dimer and H-CRP levels, suggesting possible development of inflammation and prothrombogenic reaction attributable to a subway environment.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.11a
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• pp.174-177
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• 2007

In this paper the noise characteristics of metro train is investigated experimentally. It is primarily aimed at observing the squealing noise radiation of each wheel when the vehicle pass the curve sections. This will be used to understand the noise excitation mechanism at the contact area between squealing wheels and rails which induce squeal noise at curve sections. To identify the related key parameters and boundary conditions on-board monitorings of the noise, vibration of the wheel and bogie and displacement behaviour of the wheels and rails have been done. In this paper only noise measurement and results are discussed. From spectrogramms squeal noise due to creepage and noise due to flange contact of the wheels could be identified. At the moment of the curve passing the highest squeal levels are found on the front inner wheel. However since curve noise depends on variable factors more analyses will be followed to identify the squealing wheels and the noise excitation.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.19 no.1
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• pp.85-93
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• 2009

There are many curves in Seoul subway system. Therefore, the noise from subway system in curved line gives displeasure to passenger. The subway noise in curved line is affected not only by rail condition but also wheel condition and dynamic characteristics. The railway curving noise can be divided into 2 categories. The first is the noise due to stick-slip between wheel tread and rail head, and the second is one by wheel flange contact on rail side. Because of these phenomena - stick-slip and wheel flange contact - wheels are worn seriously. In this study the curving noise was reviewed by using eigen-mode of wheel and waterfall plot which shows noise level in time-frequency domain. And also those were reviewed in viewpoint of stick-slip noise and wheel flange contact noise. Finally, the relationship between curving noise and wheel wear was studied.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2000.04a
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• pp.147-148
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• 2000

인구의 도시집중화에 따른 교통문제와 생활공간의 확보문제가 서울시가 가지고 있는 여러 가지 문제들 중의 하나이다. 이중 교통문제의 해결을 위해 서울시가 추진하고 있는 정책중 지하철 건설은 밀집화된 시의 공간활용 측면에 있어서 필연적이라고 할 수 있다. 서울시 지하철은 1974년 제 1호선 개통이래 1999년 7월에 제 8호선이 완전 개통됨으로서 40% 이상의 높은 수송 분담율을 기록하고 있다. 그러나 이러한 양적인 증가에 반해 공간적인 밀폐성으로 인한 대기, 소음, 진동 등의 환경 위해성이 논란의 대상이 되고 있다. (중략)

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2003.05a
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• pp.1197-1200
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• 2003

Urban subways usually make environmental problems because subway vibrations are transmitted to building structures. However, when the buildings are designed, vibrations due to subway are not usually considered in advance. This results in many environmental vibration problems after buildings are constructed. This study was carried out to set up and evaluate a pre-assessment technique for the environmental impact of urban subway vibration on newly planned buildings near a subway line. for this purpose, semi-emperical method was set up and vibration measurements were made on site in accordance with construction schedule. Computer simulation was also performed using ANSYS software to predict the building vibration and compared with the measured results for evaluation of the pre-assessment technique.