• 한국소음진동공학회논문집
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• 제15권6호
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• pp.738-748
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• 2005

The ship radiated noise level fluctuates by the difference of interference and reverberation according to measurement methods and environmental conditions. These phenomena cause error of the source level estimation even in the same environment conditions. This paper describes a quantitative analysis and a reduction method for an error value to the source level estimation in spatial and temporal interference environment. The design criteria of the radiated noise measurement array composed of omni-directional hydrophones and the source level accuracy in the deep water range are given. The source level accuracy in the shallow water range is also derived based on the statistical model of the multiple reflection paths. The results are verified using the water tank experiment and the sea trial.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2012년도 춘계 학술논문 발표대회
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• pp.165-167
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• 2012

The purpose of this study is introduction of social and economic benefits of environmental improvements of Korea green road certification system. Focus of Evaluation Criteria is possibility of quantification on environmental improvements. Proposed evaluation items is noise, air pollution, water quality, ecological and green spaces, waste, and space resistance. The results of this study is expected to be used to support of Green Roads Rating System in korea.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 1997년도 춘계학술대회논문집; 경주코오롱호텔; 22-23 May 1997
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• pp.362-369
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• 1997

In the case of a precision equipment, it requires a vibration free environment to provide its proper function. Especially, lithography and inspection devices, which have sub-nanometer class high accuracy and resolution, have come to necessity for producing more improved giga class semiconductor wafers. This high technology equipments require very strict environmental vibration standard in proportion to the accuracy of the manufacturing, inspecting devices. The vibration criteria of high sensitive equipment should be expressed in the form of 'exactness' and 'accuracy', because this is made basic data in the use of building structure design. This paper made a study on the specification of high sensitive equipment and proposed a contents of the specification.

• Earthquakes and Structures
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• 제23권3호
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• pp.315-328
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• 2022

Structures designed for wind have an opposite design approach to those designed for earthquakes. These structures are usually reliable if they are constructed in an area where there is almost no or less severe earthquake. However, as seismic activity is unpredictable and it can occur anytime and anywhere, the seismic safety of structures designed for wind must be assessed. Moreover, the design approaches of wind and earthquake systems are opposite where wind design considers higher stiffness but earthquake designs demand a more flexible structure. For this reason, a novel Machine learning framework is proposed that is used to assess and classify the seismic safety of the structures designed for wind load. Moreover, suitable criteria is defined for the design of wind resistance structures considering seismic behavior. Furthermore, the structural behavior as a result of dynamic interaction between superstructure and substructure during seismic events is also studied. The proposed framework achieved an accuracy of more than 90% for classification and prediction as well, when applied to new structures and unknown ground motions.

• 소음진동
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• 제6권3호
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• pp.363-373
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• 1996

In the case of a precision equipment, it requires a vibration free environment to provide its proper function. Especially, lithography and inspection devices, which have sub-nanometer class high accuracy and resolution, have come to necessity for producing more improved giga class semiconductor wafers. This high technology equipments require very strict environmental vibration standard in promotion to the accuracy of the manufacturing, inspecting devices. The vibration criteria are usually obtained either by the real vibration exciting test on the equipment or by the analytical calculation. The former is accurate but requires a great deal of time and efforts while the latter lacks reliability. This paper proposes a new method to solve this problem at a time. The permissible vibration level to a precision equipment can be easily obtained by analyzing the process of Frequency Response Function(FRF). This paper also demonstrates its effectiveness by applying the proposed method to finding the permissible vibration criteria of a Computer Hard Disk Drive.

• 한국지반환경공학회 논문집
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• 제5권3호
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• pp.5-15
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• 2004

SIP 공법이 국내에서 저소음 저진동 말뚝공법으로 널리 사용되고 있지만 품질관리기준이 명확히 정립되지 못하고 실무자들의 공법의 원리에 대한 이해 부족으로 시공시 혼선을 초래하고 있어 공법이 본래 가진 지지력을 충분히 발휘되지 못하고 있다. 이러한 문제점을 개선하기 위하여 2002년에 대한주택공사에서는 SIP 공법의 시공 및 재하시험기준을 개선하였다. 개선된 기준에 의하여 현장에 시공된 SIP 말뚝에 대하여 재하시험을 통하여 지지력을 평가한 결과 이전 방법으로 시공된 말뚝에 비하여 시공하중의 설계만족도 및 지지력 특성이 크게 향상된 것을 확인할 수 있었으며 이를 설계에 반영하면 기초 공사비도 절감할 수 있는 것으로 나타났다. 향상된 지지력 특성을 설계에 반영하기 위하여 재하시험결과를 국내에서 많이 사용하고 있는 말뚝 설계식들과 신뢰성 분석을 실시하여 적합식을 찾고자 하였다. 분석결과 개선된 기준으로 시공된 SIP 말뚝은 Meyerhof(1976)의 타입말뚝 설계식과 유사한 지지거동을 하는 것으로 나타났다.

• 환경영향평가
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• 제4권3호
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• pp.31-39
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• 1995

Environmental Impact Assessment (EIA) is composed of various procedures, such as screening, scoping, inventory survey, prediction, assessment, alternative assessment, mitigation measures, and post management. Environmental monitoring data for air quality or water quality, etc. is applied in the EIA process, especially in prediction and post management. As an effective tool of environmental monitoring, the remote sensing method, introduced recently, was used in collecting nationwide data concerning ecosystem and land use. This article explains the current monitoring status in Korea. Monitoring factors include air quality, water quality, soil, ocean, odor, noise, and ecosystems. This report explains the organization of the environmental monitoring system managed by the Ministry of Environment in Korea. Furthermore, it shows the environmental criteria and environmental policies applied to EIA in Korea.

• 한국산업보건학회지
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• 제30권2호
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• pp.174-184
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• 2020

Objectives: The purpose of this study was to improve the working environment by identifying the work satisfaction of the cleaning workers of the aircraft and measuring and assessing the harmful factors of the cleaning process. Methods: We asked 23 cleaning companies for questionnaires and got 100 answers from 5 companies. The A-E Airline health manager has been contacted to establish a site survey schedule. The in-flight and lounge were measured using direct reading equipment. The harmful factor to be measured are noise, dust, temperature, volatile organic compound, total airborne bacteria, and total airborne bacteria. Results: Uncomfortable positions when replacing blanket, cleaning the table, and cleaning the floor have been identified as factor that reduce work satisfaction. Noise when replacing newspapers and cleaning toilets has been identified as a factor that lowers work satisfaction. Temperature and humidity were found to reduce work satisfaction during in-flight disinfection. Measurements of aircraft cabin and lounge with direct read equipment have shown that none of the items exceed the exposure criteria. Conclusions: As a result of measuring direct-reading equipment, no items exceeded the exposure criteria for each harmful factor. A clear survey of the working environment is required based on the results, and additional research is needed using personal sample measurement.

• 한국신뢰성학회지:신뢰성응용연구
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• 제9권3호
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• pp.233-248
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• 2009

PAM(Power Amplifier Module) is the important part of a mobile phone transmitter. It amplifies the strength of signal transmitting from a mobile phone to base stations enough to resist noise or interference. In this paper reliability assessment criteria for the PAM are established in terms of quality certification test and lifetime test. The former quality certification test comprises general performance test and environmental test. Items which pass the test undergo lifetime test which guarantees the extent of mean lifetime with certain confidence.

• 조명전기설비학회논문지
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• 제13권2호
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• pp.24-31
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• 1999

본 논문은 전력설비, 특히 송전선로에 의해서 발생되는 전기환경장해의 특성과 이것의 제한기준에 관한 연구로서, 전기환경기준을 만족하는 송전선로 최적도체선정에 기본이 되며 전기환경장애 민원의 주 항목이 되는 가청소음, 라디오 및 TV장해, 정전유도 그리고 전자유도에 대한 국내 및 세계각국의 관련기준과 법규를 조사, 비교하고 초고압 실증시험선로에서 도출된 결과를 통하여 우리나라 실정에 맞는 전력설비 전기환경 설계기준(안)을 제시하였다.