• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2001년도 춘계학술대회논문집
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• pp.374-379
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• 2001

The satellite electronic equipment is exposed to high level random vibration environment during the launch of spacecraft. The random vibration can cause damage of electronic equipment. Thus very careful consideration on the launch environment, especially for high level random vibration, is required in the design stage of transponder equipments of communication satellite. For the structural integrity of the communication satellite transponder equipment under qualification level random vibration, Finite Element analysis was carried out using the commercial code, MSC/Nastran and ANSYS and stress levels are presented. In order to validate the femodel, modal test was also performed and compared with numerical results.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2000년도 춘계학술대회논문집
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• pp.1180-1184
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• 2000

The dynamic design analysis method (DDAM) to analyze and evaluate shock response of the equipment system mounted in ships are discussed. Theoretical background of the DDAM based on the general shock response analysis was introduced. Spectrum dip effect between the equipment system and supporting structure was specially focused being peculiar to general shock response analysis. Actual shock design values used in the DDAM were reviewed in their category, general trend and establishing process. Aspects of DDAM analysis using MSC/NASTRAN were shortened. As a conclusion DDAM is regarded as a reasonable way of analysis for the onboard equipment system due to the underwater shock.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2000년도 춘계학술대회논문집
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• pp.1246-1251
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• 2000

High level random vibration environments induced while launching of spacecraft can damage sensitive electronic equipment very rapidly, unless the equipment is properly packaged. Thus very careful consideration on the launch environment, especially for high level random vibration, is required in the design stage of electronic equipment of spacecraft. This paper describes the development process of Solar Array Regulator for KOMPAT-2, which is designed and tested by Korean engineers. Both analytical and experimental techniques are introduced in this paper.

• 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.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2005년도 춘계학술대회논문집
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• pp.100-103
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• 2005

The aim of the product noise labeling is to harmonize the noise control act relating to noise emission standards, conformity assessment procedure, marking, technical documentation and collection of data concerning the noise emission in the environment of equipment for use outdoors. It will contribute to the smooth functioning of the internal market, while protecting human health and well-being.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2018년도 춘계학술대회
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• pp.179-181
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• 2018

디지털 영상장비는 사회의 폭넓은 분야에서 다양한 목적으로 사용되며, 4차 산업혁명의 중요한 요소로 자리 잡고 있다. 영상장비의 데이터는 여러 가지 원인으로 잡음에 노출되며, 이러한 잡음은 장비의 정확성에 영향을 끼쳐 오차를 유발하며 신뢰도를 저하한다. 본 논문에서는 고밀도의 Salt and Pepper 잡음을 효과적으로 제거하기 위해 방향성 유효 화소를 기반으로 한 알고리즘을 제안하였다. 기존 방법들은 Salt and Pepper 잡음의 밀도가 높아지면서 성능이 저하하는 모습을 보였다. 반면, 제안하는 방법은 고밀도 Salt and Pepper 잡음 환경에서도 방향성 유효 화소를 고려한 디노이징을 진행하여 기존 방법보다 잡음 제거성능이 우수하였다. 실험 결과는 제안한 알고리즘이 기존 방법들에 비해 우수함을 보여주며, 확대 영상을 통해 성능을 확인하였다.

• 한국정보통신학회논문지
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• 제22권10호
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• pp.1320-1326
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• 2018

디지털 영상장비는 4차 산업혁명의 중요한 요소로, 사회의 폭넓은 분야에서 다양한 목적으로 사용되고 있다. 디지털 영상장비의 데이터는 사용 환경 및 처리 과정에서 여러 가지 원인으로 잡음에 노출되며, 이러한 잡음은 장비의 출력과 처리 과정에 영향을 끼치며 오차를 유발하여 신뢰도를 저하한다. 본 논문에서는 채널 전송 과정에서 주로 발생하는 잡음인 임펄스 잡음을 제거하여 효과적으로 영상을 복원하는 알고리즘을 제안하였다. 제안한 알고리즘은 잡음판단과 방향성 마스크를 이용한 유효 화소의 탐색으로 영상 복원이 진행되며, 검출된 유효 화소에 따라 구해진 추정치의 비교 분석을 통해 최종 출력을 계산한다. 기존 방법과 제안하는 알고리즘의 비교를 위해 시뮬레이션을 진행하였으며, 성능을 확인하기 위해 PSNR 및 프로파일을 통하여 분석하였다.

• 국제학술발표논문집
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• The 8th International Conference on Construction Engineering and Project Management
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• pp.455-462
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• 2020

Noise which is unwanted sound is a serious pollutant that can affect human health, as well as the working and living environment if exposed to humans. However, current noise management on the construction project is generally conducted after the noise exceeds the regulation standard, which increases the conflicts with inhabitants near the construction site and threats to the safety and productivity of construction workers. To overcome the limitations of the current noise management methods, the activities of construction equipment which is the main source of construction noise need to be managed throughout the construction period in real-time. Therefore, this paper proposed a framework for automatically detecting noise sources in construction sites in real-time based on convolutional neural networks (CNNs) according to the following four steps: (i) Step 1: Definition of the noise sources; (ii) Step 2: Data preparation; (iii) Step 3: Noise source classification using the audio CNN; and (iv) Step 4: Noise source detection using the visual CNN. The short-time Fourier transform (STFT) and temporal image processing are used to contain temporal features of the audio and visual data. In addition, the AlexNet and You Only Look Once v3 (YOLOv3) algorithms have been adopted to classify and detect the noise sources in real-time. As a result, the proposed framework is expected to immediately find construction activities as current noise sources on the video of the construction site. The proposed framework could be helpful for environmental construction managers to efficiently identify and control the noise by automatically detecting the noise sources among many activities carried out by various types of construction equipment. Thereby, not only conflicts between inhabitants and construction companies caused by construction noise can be prevented, but also the noise-related health risks and productivity degradation for construction workers and inhabitants near the construction site can be minimized.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2002년도 추계학술대회논문초록집
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• pp.395.2-395
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• 2002

Recently, as size of building structure becomes larger, mat area of building structure is supported on Inhomogeneous foundation. The equipment machineries in building are mostly on basement story. The slab of the lowest basement story with equipment machineries is considerded as concentrated masses on plate supported on foundation. In this paper. vibration analysis of rectangular thin plate is done by use of rectangular finite element with 4 nodes. (omitted)

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2014년도 춘계학술대회 논문집
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• pp.348-349
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• 2014

In general, there has been a lot of research concerned about the gear noise known to be proportional to gear transmission error for external gears likewise spur, helical gear, and hypoid gears. But, In the case of planetary gear set, gear noise study is insufficient because of the difficulty of designing, manufacturing, and understanding of the its mechanical system. This study is aimed to develop the transmission error measurement equipment for the planetary gear sets used in the automatic transmission. By comparing the results of the transmission error and noise objectively, user could select the optimized planetary gear set which has quiet noise level before manufacturing the automatic transmission.