• 소음진동
• /
• 제7권4호
• /
• pp.597-604
• /
• 1997

Ground vibrations induced from railroad were measured to get the basic data that can be usde to prepare countermeasures for solving environmental vibration problems. Vibration levels were measured simultaneously at three points in double distances from railroad. These data were analuzed with the kinds of trains, media to understand the magnitudes and characteristics of distance attenuation of railroad vibrations.

• 한국소음진동공학회:학술대회논문집
• /
• 한국소음진동공학회 2002년도 춘계학술대회논문집
• /
• pp.768-771
• /
• 2002

국외 환경 소음과 진동은 이미 세계보건기구(WHO)와 UN산하 환경기관에서 선언한 바와 같이 “전세계인의 문제”(“global issues”)로 분류 인식하고 있으며, 이들 문제점들에 대한 접근은 선진국들의 국민 복지정책의 가장 핵심적 요소로 관리하고 있다. 예를 들어, WHO가 출판한 공중소음에 대한 지침서［1］, 그리고 유럽공동체의 전문가 그룹이 작성한 보고서［2］들은 최근의 환경소음에 대한 새로운 접근의 필요성, 새로운 측정 및 평가 방법, 그리고 인체에 미치는 복합적 영향들의 새로운 평가 기법 개발, 그리고 환경 개선을 위한 장기적 계획과 실천 방안들을 구체적으로 제시하고 있다.(중략)

• 한국소음진동공학회:학술대회논문집
• /
• 한국소음진동공학회 2005년도 춘계학술대회논문집
• /
• pp.809-812
• /
• 2005

This paper explains environmental tests of vessel-launched missiles, verifying if a fully assembled missile performs properly from disturbance on delivery by vehicles or naval vessels. We also have operated vibration tests by ground and naval transportation as well as shock tests by naval transportation before firing. The environmental tests have adopted Military Standard Specification and confirmed missile's reliability by performance tests, followed by missile's development. However, this significant testing which have meaning was dong by the missile's body and not with parts.

• 환경영향평가
• /
• 제22권4호
• /
• pp.369-379
• /
• 2013

Noise and vibration problems at the construction site, expansion of construction scale and frequency of urban construction is increased, has given the damage to local residents. Also, the result of civil complaint about noise and vibration that occurred in 2011 was 56,244; it is showing an increasing trend of more than 4% annually. In particular, the construction noise and vibration, the civil complaints of around construction site accounts for 64.6%(36,353), are harmful to the tranquility of living environment. As a result, the government has managed to strengthen the regulatory standard of construction noise (65dB(A), Day-time) from 2011. However, the regulatory standard of construction noise and vibration does not meet and also complaints related the construction noise and vibration not decreased. Because the management system can be applied to the construction site is insufficient and a shortage of manpower. In this study, investigated the status and problems of the regulatory standards related to construction noise and vibration, we propose an efficient management plan of construction noise and vibration.

• 한국소음진동공학회:학술대회논문집
• /
• 한국소음진동공학회 2012년도 추계학술대회 논문집
• /
• pp.587-591
• /
• 2012

Review of practical vibration test methods those applied in various industrial fields - such as automotive industry, electrics and electronics industry, defense industry and aerospace industry - is described on this paper. Swept sine test, random vibration test and advanced vibration techniques are explained according to their parametric values and also application fields of each test method are suggested by the characteristic of each method. For more proper application of each test method, standardized test specifications should be always reviewed and revised according to the transition of environmental factors.

• 한국건설관리학회논문집
• /
• 제5권6호
• /
• pp.110-117
• /
• 2004

건설사업과 환경보전은 대립적인 요소를 많이 가지고 있어 건설사업으로 인한 환경 분쟁이 급증하고 있으며 소음 $\cdot$ 진동에 관한 분쟁이 대부분을 차지하고 있다. 이러한 분쟁과 민원은 기업에 대한 부정적 이미지, 사업의 지연 $\cdot$중단, 배상액 지불 등 막대한 경제적 손실을 가져오므로 치밀하게 관리할 필요가 있다. 본 논문에서는 문헌조사를 통하여 이론적인 고찰을 실시하고, 소음 $\cdot$진동 관련 법령을 정리 분석하여 건설사업과 관련된 검토항목을 추출하였다 또한 사전 환경성 검토 환경영향평가 항목과 분쟁조정에 관한 통계자료를 검토 $\cdot$분석하여 건설사업의 추진단계별 소음 $\cdot$ 진동 관리방안을 제시하였다 이는 건설사업을 수행함에 있어서 소음 진동에 관한 규제사항의 정확한 준수와 분쟁 및 민원의 발생을 최소화하는데 활용될 수 있을 것이다.

• Smart Structures and Systems
• /
• 제31권4호
• /
• pp.393-407
• /
• 2023

To assess structural condition in a non-destructive manner, computer vision-based structural health monitoring (SHM) has become a focus. Compared to traditional contact-type sensors, the advantages of computer vision-based measurement systems include lower installation costs and broader measurement areas. In this study, we propose a novel computer vision-based vibration measurement and coarse-to-fine damage assessment method for truss bridges. First, a deep learning model FairMOT is introduced to track the regions of interest (ROIs) that include joints to enhance the automation performance compared with traditional target tracking algorithms. To calculate the displacement of the tracked ROIs accurately, a normalized cross-correlation method is adopted to fine-tune the offset, while the Harris corner matching is utilized to correct the vibration displacement errors caused by the non-parallel between the truss plane and the image plane. Then, based on the advantages of the stochastic damage locating vector (SDLV) and Bayesian inference-based stochastic model updating (BI-SMU), they are combined to achieve the coarse-to-fine localization of the truss bridge's damaged elements. Finally, the severity quantification of the damaged components is performed by the BI-SMU. The experiment results show that the proposed method can accurately recognize the vibration displacement and evaluate the structural damage.

• Computers and Concrete
• /
• 제32권1호
• /
• pp.75-85
• /
• 2023

This work utilizes simplified higher-order shear deformation beam theory (HSDBT) to investigate the vibration response for functionally graded carbon nanotube-reinforced composite (CNTRC) beam. Novel to this work, single-walled carbon nanotubes (SWCNTs) are distributed and aligned in a matrix of polymer throughout the beam, resting on a viscoelastic foundation. Four un-similar patterns of reinforcement distribution functions are investigated for the CNTRC beam. Porosity is another consideration taken into account due to its significant effect on functionally graded materials (FGMs) properties. Three types of uneven porosity distributions are studied in this study. The damping coefficient and Winkler's and Pasternak's parameters are considered in investigating the viscosity effect on the foundation. Moreover, the impact of different parameters on the vibration of the CNTRC beam supported by a viscoelastic foundation is discussed. A comparison to other works is made to validate numerical results in addition to analytical discussions. The findings indicate that incorporating a damping coefficient can improve the vibration performance, especially when the spring constant factors are raised. Additionally, it has been noted that the fundamental frequency of a beam increases as the porosity coefficient increases, indicating that porosity may have a significant impact on the vibrational characteristics of beams.

• Structural Engineering and Mechanics
• /
• 제11권6호
• /
• pp.617-636
• /
• 2001

For the potential application of smart materials to seismic structural control, this paper reviews seismic control techniques for civil engineering structures, and developments of smart materials for vibration and noise control. Analytical and finite element methods adopted for the design of distributed sensors/actuators using piezoelectric materials are discussed. Investigation of optimum position of sensors/actuators and damping are also outlined.

• 한국환경과학회지
• /
• 제13권6호
• /
• pp.581-589
• /
• 2004

This paper describes the amount of food consumption and the change of total weight of abalone under a vibration with noise that can be occurred due to piling work. This experiment was conducted in the aquarium in Yosu National University. In normal situation the juvenile stage shell's(total length is 1～1.5cm) amount of food consumption was 0.81g, the middle stage shell(total length is 3～3.5cm) was 13.61g, and the adult stage shell (Total length is 7～7.5cm) was 43.l9g per 5 organisms in 24 hours, while the experimental group was observed low numerical value compared normal groups. The abalones' food consumption and total weight in both groups, the intermittent and continuance impact with noise and vibration, was reduced during this experiment. The abalones' food consumption and total weight in the experimental groups without vibration were recorded slightly high numerical value than the experimental groups with noise and vibration. Based on this experimental data we could conjecture the noise and vibration are harmful factors to bring up a physiological stress to abalones. Especially, the vibration impact by piling works could produce a considerably unfavorable effect to the abalones than noise impact.