• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2001년도 춘계학술대회논문집
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• pp.577-582
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• 2001

Identification of damage of structures has recently received considerable attention in the light of maintenance and safety assessment under service loads. In buildings, the current techniques of safety assessment largely depend on partial experiments such as visual inspection, destructive and nondestructive tests which lead to overconsumption of time and cost as well as higher labor intensity. Therefore, a new trial for safety assessment is urgently needed today. In this respect, the vibration characteristics of buildings have been applied steadily to obtain a damage index of the whole building, but it cannot be established as a practical method until now. This study is aimed at investigating the application of damage identification methods using vibration characteristics of building. Numerical tests are performed on a apartment building. From the test results, it is observed that severity and location of damage can be estimated with a relatively small error by using natural frequency and mode shape data.

• Nuclear Engineering and Technology
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• 제45권2호
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• pp.249-256
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• 2013

In accordance with the US Nuclear Regulatory Commission (US NRC), Regulatory Guide 1.20, the reactor vessel internals comprehensive vibration assessment program (RVI CVAP) has been developed for an Advanced Power Reactor 1400 (APR1400). The purpose of the RVI CVAP is to verify the structural integrity of the reactor internals to flow-induced loads prior to commercial operation. The APR1400 RVI CVAP consists of four programs (analysis, measurement, inspection, and assessment). Thoughtful preparation is essential to the measurement program, because data acquisition must be performed only once. The optimized design of a vibration and stress measurement system for the RVI CVAP is essential to verify the integrity of the APR1400 RVI. We successfully designed a vibration and stress measurement system for the APR1400 RVI CVAP based on the design materials, the hydraulic and structural analysis results, and performance tests of transducers in an extreme environment. The measurement system designed in this paper will be utilized for the APR1400 RVI CVAP as part of the first construction project in Korea.

• 한국소음진동공학회논문집
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• 제25권9호
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• pp.599-605
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• 2015

U.S. Nuclear Regulatory Commission(NRC), Regulatory Guide(RG) 1.20(Rev.3, 2007년)은 원자로 냉각재계통, 주증기, 주급수 및 복수시스템의 주요 배관 및 기기에 대하여 압력변동 및 진동에 의한 잠재적 유해효과에 대한 평가를 요구한다. 그러나 증기발생기와 연결된 주증기, 주급수 및 복수시스템의 주요 배관 전체에 대하여 상세 해석하는 것은 매우 복잡하여 한계가 있다. 이 논문은 APR1400 원전의 종합진동평가(comprehensive vibration assessment program, CVAP)를 수행하기 위하여 증기발생기에 연결된 2차측 주요 배관의 음향공진과 펌프유발진동을 위한 간이평가 방법에 관한 것이다. 이 논문에서는 이러한 배관시스템의 잠재적 진동 원인이 무엇인지, 음향공진과 펌프유발진동의 가능성을 예방하기 위한 간이평가 방법은 무엇인지를 고찰하고자 한다. 이 논문은 APR1400 원전 증기발생기와 연결된 주증기 및 주급수 배관의 유동유발진동 간이평가를 위해 사용될 것으로 판단된다.

• 환경영향평가
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• 제10권4호
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• pp.305-317
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• 2001

Effects on increased noise influenced residents on the urban areas as well as the rural areas because of rapidly increasing traffic volume and newly-constructed road. The object of this study is to better establish environmental policy for the year 2000s through analyzing current environment administration system in the field of noise and vibration. Noise and vibration administration system in Korea is composed of various standards in areas of noise environment, traffic noise regulation, living noise regulation, factory noise and vibration regulation, and aircraft noise regulation. Furthermore, there exists environment noise and vibration monitoring networking system. This study is to improve noise and vibration administration system through analyzing present condition and problems. This study suggests improved noise and vibration administration system by achieving four steps ; 1) goal establishment in noise and vibration administration system; 2) development of reduction mitigation method; 3) estimation of reduction mitigation method; 4) establishment of enforcement method. Proposed "Noise and Vibration Policy Committee" should be established to harmonize noise and vibration policy on scientific basis for the $21^{st}$ century.

• 환경영향평가
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• 제22권4호
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• pp.381-387
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• 2013

In order to improve the environmental vibration, it is necessary to method for not only reduce the vibration source, but also control the vibration path. In this study, we used borebole for estimate the vibration reduction. And also, we analyzed displacement and vibration velocity caused by the position of borehole as well as the condition of borehole in ground structure. Visual FEA(Finite Element Analysis) program was used in this numerical analysis. The results are as follows : The displacement magnitude and X, Y direction displacement were represented to different results due to the condition and position of borehole, and were represented to the lowest values when the position of borehole is the most close condition from the vibration source. And also, the vibration velocity was decreased as using borebole in ground structure. The isolation efficiency of the vibration was calculated to maximum 18.40% when borehole was established to the most close position from the vibration source and the receive point.

• 한국소음진동공학회논문집
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• 제21권8호
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• pp.708-713
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• 2011

U.S. nuclear regulatory commission(NRC) regulatory guide(RG) 1.20 requires a comprehensive vibration assessment program(CVAP) for use in verifying the structural integrity of reactor vessel internals(RVI) for flow-induced vibrations prior to commercial operation. The CVAP program consist of vibration and fatigue analysis, a vibration measurement program, an inspection program, and a correlation of their results. One of the main purposes of the analysis program is to select measurement locations, however measurement locations can not be determined by only analysis results, therefore we developed selection criteria of measurement locations for advanced power reactor 1400(APR1400) RVI CVAP, It will be used to select measurement locations and instrument types for APR1400 RVI CVAP.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2004년도 추계학술대회논문집
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• pp.611-614
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• 2004

In this study, ambient vibration tests are carried out to replace the current bridge integrity assessment using controlled vehicle test, which requires the traffic control and may induce public complains. Ambient vibration tests and output-only modal identification can be very effective approach to evaluate the bridge integrity because the ambient vibration tests can be performed very easily without trafnc control. The bridges in test road of Jungbu Inland Highway were tested and the results are discussed here.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2006년도 춘계학술대회논문집
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• pp.750-753
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• 2006

Noise prediction is required as part of an environmental impact assessment. However, there has not been any comprehensive study or review en the major factors of specific vehicles affecting traffic noise so that there is difficulty when trying to figure out the source of noise. This study was to evaluate the noise effect of specific vehicles passing through a certain road by using noise map.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2009년도 춘계학술대회 논문집
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• pp.608-609
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• 2009

• 환경영향평가
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• 제23권3호
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• pp.169-176
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• 2014

The purpose of this study is to estimate the vibration reduction effect of the borehole which is controlled the vibration propagation in the ground. For this study, we measured the vibration velocity before and after the borehole installation. The results are as follows: The peak particle velocity(PPV) and peak vector sum(PVS) was reduced by the borehole. And also, the deviation of vibration velocity before and after the borehole installation showed large values in longitudinal and vertical component depending on the receive distance, and increased depending on the size of vibration energy. Finally, the vibration isolation efficiency was 25~35 percentage at 1.5m receive distance, and was 4~14 percentage at 3.0m receive distance. It was found that the vibration isolation efficiency was good in small vibration energy, but was not good at long receive distance.