• 대한조선학회논문집
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• 제47권1호
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• pp.93-98
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• 2010

In this paper, PLC which can be installed easily and is stable to transfer datum, is tested for approving its application in a real ship. Internet access service, CCTV monitoring, light control and huge sensor communications are needed for enhancing the convenience and safety of passengers and crew in ships. In order to apply PLC in ships, we surveyed some noises interrupting PLC in ships and investigated the PLC characteristics. The Hannara, a training ship of Korea Maritime University, was used for the test. We measured and analyzed blocking noises using by NI's SCXI-1001. When noises of specific frequency band occurred near the PLC frequency band, PLC transfer capacity was low for mass datum. We developed and verified some methods to apply PLC in a ship under lots of noises.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 추계학술대회 논문집 전기물성,응용부문
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• pp.217-219
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• 2005

To detect partial discharge of 154kV joint box, we have made experiment by using the HFCT sensor. Generally the signals which are detected in partial discharge test of underground power transmission cable are accompanied with both noises of high voltage and noises of surrounding power cable. The most noise in near to end part of joint box is corona, beside other noises flowed from surrounding area. Partial discharge test is difficulty due to these noises. First, we test reliability on both injection of calibration signal in NJB and removal of low frequency. After that, we had analyzed frequencies by measuring signals in IJB with 300[m] distance from NJB. Also we had measured S/N ratio by using the indirected injection method of calibration signal in IJB. In this experiment, two measurement methods were difference of detection acquisition, but these had the equal frequency properties.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2005년도 추계학술대회 논문집 Vol.18
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• pp.142-144
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• 2005

To detect partial discharge of 154kV joint box, we have made experiment by using the Al-foil electrode sensor. Generally the signals which are detected in partial discharge test of underground power transmission cable are accompanied wi th both noises of high voltage and noises of surrounding power cable. The most noise in near to end part of joint box is corona, beside other noises flowed from surrounding area. Partial discharge test is difficulty due to these noises. First, we had used Al-Foi1 sensor on middle joint box of 154[kV] underground transmission power cable, and then analyzed reliability of calibration signal by using the Al-Foi1 electrode sensor of NJB. From above results, decrement properties measured highly. But incase of injecting calibration signal of 500[pC] after measuring signals in IJB, the S/N ratio had about 25[dB] acquisition.

• 대한기계학회논문집
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• 제13권1호
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• pp.40-47
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• 1989

본 연구에서는 적극적인 소음 방지 대책으로 승용차용 교류발전기의 소음을 저감시키기 위한 첫단계로 각 부품 별 주요 소음 발생 기여도를 회전속도에 따른 주파수 분석을 통해 측정하였다. 교류발전기의 소음은 크게 자기 소음, 기계소음, 통풍 소음으로 구분할 수 있다. 이들 소음은 전자기 부품의 설계와 교류발전기의 구조 설계, 각 부품의 가공 정밀도, 그리고 전체 구조물의 결합 상태와 밀접한 관련을 갖고 있다.

• 지구물리와물리탐사
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• 제16권1호
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• pp.1-5
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• 2013

탄성파 자료처리 과정에서 겹쌓기는 신호대 잡음비율과 영상의 질을 개선하는데 중요한 역할을 한다. 하지만 기존의 겹쌓기 방법은 다양한 분포의 잡음과 특이치 잡음을 만족스러운 수준으로 제거하지는 못한다. 본 논문에서는 특이치에 강인함을 보이는 중앙값 처리와 다양한 분포의 잡음 제거에 효과적인 국지적 상관을 이용한 가중 겹쌓기법을 결합하여, 강인하면서도 최적인 가중 겹쌓기법을 소개한다. 제안한 방법을 합성 자료에 적용하여 다양한 분포의 잡음과 특이치 잡음 모두를 효과적으로 제거함을 확인할 수 있었다.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2013년도 추계학술대회
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• pp.268-270
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• 2013

Wibro 기술의 개발 및 보급으로 인하여, 디지털 기술이 여러 분야에서 활용되고 있다. 디지털 영상은 전송 및 저장하는 과정에서 다양한 잡음에 의해 훼손되며, 영상복원은 영상에 첨가되는 잡음을 제거하여 잡음이 영상에 미치는 영향을 줄이는 것이다. 영상복원을 위해, 여러 가지 방법들이 제안되었으나 기존의 방법들은 잡음제거 특성이 미흡하다. 따라서 본 논문에서는 효과적으로 잡음을 제거하기 위해 잡음판단을 거쳐, 잡음일 경우, 마스크 크기를 확대시키는 적응 메디안 필터 알고리즘을 제안하였다. 그리고 시뮬레이션을 통해 기존의 방법들과 비교하여 제안한 알고리즘의 우수성을 입증하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 춘계학술대회 논문집 전기설비전문위원
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• pp.75-78
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• 2007

To detect partial discharge of 154kV joint box, we have made experiment by using the HFCT sensor. Generally the signals which are detected in partial discharge test of underground power transmission cable are accompanied with both noises of high voltage and noises of surrounding power cable. The most noise in near to end part of joint box is corona, beside other noises flowed from surrounding area. Partial discharge test is difficulty due to these noises. First, we test reliability on both injection of calibration signal in NJB and removal of low frequency. After that, we had analyzed frequencies by measuring signals in IJB with 300[m] distance from NJB. Also we had measured S/N ratio by using the indirected injection method of calibration signal in IJB. In this experiment, two measurement methods were difference of detection acquisition, but these had the equal frequency properties.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 춘계학술대회 논문집 전기설비전문위원
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• pp.79-81
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• 2007

To detect partial discharge of 154kV joint box, we have made experiment by using the Al-foil electrode sensor. Generally the signals which are detected in partial discharge test of underground power transmission cable are accompanied with both noises of high voltage and noises of surrounding power cable. The most noise in near to end part of joint box is corona, beside other noises flowed from surrounding area. Partial discharge test is difficulty due to these noises. First, we had used Al-Foil sensor on middle joint box of 154[kV] underground transmission power cable, and then analyzed reliability of calibration signal by using the Al-Foil electrode sensor of NJB. From above results, decrement properties measured highly. But incase of injecting calibration signal of 500[pC] after measuring signals in IJB, the S/N ratio had about 25[dB] acquisition.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2005년도 추계학술대회논문집
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• pp.227-230
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• 2005

This paper describes the problems in measuring and evaluating the aviation noises and the differences on the noise characteristics between fighter and civil aircraft. From a standpoint of the duration time for aviation noise and the dynamic characteristics related with the sampling time, the measured values for landing and taking-off noises from the fighter are presented and explained in comparison with those from the civil aircraft. And also the aviation noises by the fighter and civil aircraft are evaluated by equivalent sound level and WECPNL, respectively. From the obtained results, it is recommended that the duration time and dynamic characteristics be deeply considered in evaluating and measuring the aviation noises, since they have a great influence on the final assessment results. As the number of flight is not sufficient and the noise source is strong impulse type, moreover, the aviation noise should be assessed by WECPNL.

• 한국도서관정보학회지
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• 제8권
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• pp.69-96
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• 1981

We all know that we can not keep a proper social life without language. Yet language is so much a part of our environment that we hardly realize it is there. The purpose of this study is to provide an understanding of the linguistical aspect of communication process in order to carry out a successful human relations in the operation of libraries. Human development rests upon man's capacity to digest large quantities of knowledge and it is language which allows facts to be communicated, stored, and disseminated. An attempt was made in this study to illustrate the elementary meaning-of-words aspect of communication. In order to share the most commonly agreed meanings in interpersonal communication, a careful study of semantic noises is important. In a constant struggle to meet client needs, staff and administrators, librarian must understand communication dialogues, their messages and be able to read all level of meanings. In order to perform a successful function of the librarian, to act as a link-man or communicator and to cope with its ever growing information, it is suggested that the deep understanding of the following linguistical aspect of communication elements is essential. 1. Characteristics of Language: (1) Words have different meanings to different people. (2) Words vary in the degree of abstraction. (3) Language is incomplete by its nature. (4) Language reflects not only the personality of the individual but also the culture of man's society. 2. Noises in transmitting meanings: (1) Mechanical or Technical noises. (2) Semantic Noises (3) Noises caused by the psychological factors a. attention b. perception, sensation, cognition and perceptual field. 3. Linguistic Stratum Languages differ considerably in vocabulary by the physical and cultural environment setting as well as situation of individual living. There are seven different language stratum which reflects different region, sex, age, profession, special social stratum, academic and tabooed words.