레이저 절단에서 광소자를 이용한 가공공정 모니터링

김봉채,장욱진,김재도 한국정밀공학회 1995 한국정밀공학회 학술발표대회 논문집 Vol.1995 No.11월

Development of a Broadband Self-recording Hydrophone

김봉채 한국해양과학기술원 2006 Ocean and Polar Research Vol.28 No.2

A broadband self-recording hydrophone was developed to conveniently assemble a hydrophone array for use in receiving underwater sound waves. A trigger device with an electromagnetic induction coupler was also developed to control the hydrophones operation. Main configurations and specifications of the self-recording hydrophone are introduced in this paper. We present experiment results conducted in a water tank to examine the operating behavior of the hydrophone. Some advantages are discussed when the self-recording hydrophones are used to make up a hydrophone array.

행정입법에 대한 소고

김봉채 한국공법학회 2008 公法硏究 Vol.37 No.1

오늘날 행정입법은 매우 복잡하게 전개되고 있다. 종래에는 법규성이 없다고 하는 행정규칙이사회현실의 복잡성과 전문성으로 인해 법규성이 있다고 하는 이론이 등장하고, 판례도 이를 수긍하고 있는 것이 현실이다. 그런데, 이러한 행정규칙의 법규성은 국민들의 법률생활안정과 관련하여 중대한 영향을 미칠 뿐만 아니라 권력분립의 원리에도 영향을 미쳐, 전문성ㆍ기술성을 요하는 행정영역을 전문성이 떨어지는 국회에서의 국정통제는 그 실효성이 의심스러운 것이 현실이다. 게다가 법규성을 갖는 규칙을 광범위하게 인정함으로써 실질적으로 행정입법권까지 광범위하게 인정하는 결과가 된다면 행정부의 독주를 통제할 수 없을 뿐만 아니라, 결과적으로 권력이 행정부에 집중됨으로서, 그 피해는 국민에게 고스란히 돌아오게 될 것이다. 이러한 문제의식에서 행정입법의 논의는 의미가 있을 것이다. 즉, 행정입법의 논의는 법규명령과 행정규칙의 구별기준을 명확히 함으로써, 법규에 대한 예측가능성을 높여 국민들의 법률생활의 안정에 기여하고, 한편으로 국회와 행정부 사이의 입법활동에 명확한 위임입법과 행정입법을 유도하는 것이다. 이를 위해서 첫째 행정입법, 즉 법규명령과 행정규칙은 나름대로 고유한 형식으로 존재하도록 유도하여야 한다. 일반적ㆍ추상적 규율인 법규가 규범력을 갖기 위해서는 법규에 대한 인식가능성이 있어야 하는데 이러한 형식이 인식가능성의 전제가 되기 때문이다. 둘째, 이 경우 존재형식은 헌법에서 찾아야 하고, 따라서 행정입법 중 법규명령은 헌법상의 대통령령과 부령 등 몇 가지로 한정하여야 한다. 이 경우 행정입법의 형식에 따른다 해도 이는 행정법규 제정권한이 있는 자가 법규적 내용을 엄격한 제정절차를 거쳐서 법규범형식으로 정립하여야 한다. 이것은 행정입법권을 인정한 헌법제정권력자가 지나친 행정입법의 확대를 견제하기 위해서 일정한 형식으로 제한한 것이라고 할 것이다. 셋째, 법규명령과 행정규칙의 구별은 ‘제정의 형식’에 따라 구분되어야 한다. 그 형식의 존재는 곧 법규의 수범자인 국민들의 법의 인식근거가 된다. 따라서 법규명령은 법규명령형식으로 행정규칙은 행정규칙형식으로 제정되어야 한다. 행정부의 행정규칙으로의 도피를 막으려는 의도가 있는 것이다. 또 이것은 국회에게는 입법권의 행사를 진지하고 신중하게 행사할 것을 주문하는 것이기도 하기 때문이다. Today's society, administrative legislation is spread very intricately. Because of complexity and professionalism of society actuality, administrative legislation is increased than National Assembly legislation gradually. The Supreme Court is recognizing administrative legislation. By the way, the legislation's nature of administrative regulation affects important people's stability of law's life, Because there is no possibility of anticipation. These phenomenons influenced between legislative and administrative power, It is difficult that the legislative body which is no professionalism controls the Administration which is professionalism. In addition, substantially, if we recognize administration legislative power extensively, as that power is converged in the Executive as a result, the damage may return completely to people. In these point of view, the discussion of administrative legislation may be meaning. That is, discussion about administrative legislation, doing definitely distinction standard of administrative decree and administrative regulation, On the other hand, when the National Assembly and administration legislate, they derive so that may legislate to distinguish definitely administrative decree and administrative legislation. For this, first, administrative decree and administrative regulation must exist in itself peculiar form. General and abstract legislation, because these form becomes possibility of anticipation. Second, in this case, form of existence must look for groundwork in constitutional law, and so, administrative decree must limit by some such as constitutional Presidential decree and order from a government ministry. So as to check administration legislative power, person of constituent power restricts the adminisration that extension too much. Also, the person who have enactment competence must establish, passing through strict enactment formality, administrative legislation in legislation form. Third, distinction of administrative decree and administrative injunction should be divided according to 'Form of regulation'. The Form of regulation becomes civilianizations' possibility of anticipation. Therefore, administrative decree should be established as form of administrative decree, administration regulation as form itself. Because it is that it is intention to keep away escape of administration rule of the Executive, and order to use seriously and circumspectly in event of legislative power to the National Assembly.

황해에서 저주파 음파의 해저손실 변동

김봉채 한국해양과학기술원 2007 Ocean and Polar Research Vol.29 No.2

The sound wave in the sea propagates under the effect of water depth, sound speed structure, sea surface roughness, bottom roughness, and acoustic properties of bottom sediment. In shallow water, the bottom sediments are distributed very variously with place and the sound speed structure varying with time and space. In order to investigate the seasonal propagation characteristics of low-frequency sound wave in the Yellow Sea, propagation experiments were conducted along a track in the middle part of the Yellow Sea in spring, summer, and autumn. In this paper we consider seasonal variations of the sound speed profile and propagation loss based on the measurement results. Also we quantitatively investigate variation of bottom loss by dividing the propagation loss into three components: spreading loss, absorption loss, and bottom loss. As a result, the propagation losses measured in summer were larger than the losses in spring and autumn, and the propagation losses measured in autumn were smaller than the losses in spring. The spreading loss and the absorption loss did not show seasonal variations, but the bottom loss showed seasonal variations. So it was thought that the seasonal variation of the propagation loss was due to the seasonal change of the bottom loss and the seasonal variation of the bottom loss was due to the change of the sound speed profile by season.

Variation of Underwater Ambient Noise observed at IORS Station as a Pilot Study

김봉채,최복경 한국해양과학기술원 2006 Ocean science journal Vol.41 No.3

The Ieodo Ocean Research Station(IORS) is an integrated meteorological and oceanographic observation base which was constructed on the Ieodo underwater rock located at a distance of about 150 km to the south-west of the Mara-do, the southernmost island in Korea. The underwater ambient noise level observed at the IORS was similar to the results of the shallow water surrounding the Korean Peninsula (Choi et al. 2003) and was higher than that of deep ocean (Wenz 1962). The wind dependence of ambient noise was dominant at frequencies of a few kHz. The surface current dependence of ambient noise showed good correlation with the ambient noise in the frequency of 10kHz. Especially, the shrimp sound was estimated through investigations of waveform and spectrum and its main acoustic energy was about 40dB larger than ambient noise level at 5 kHz.

휴대용 수중청음기 배열 시스템의 개발

김봉채,Kim Bong-Chae 한국음향학회 2006 韓國音響學會誌 Vol.25 No.4

수중음장의 공간적인 분포를 측정하거나 해양에서 음파의 도래방향을 탐지하기 위하여 수중청음기 배열을 사용하고 있다. 그런데 수중청음기 배열은 일반적으로 규모가 크고 가격도 고가이다. 그래서 수중청음기 배열을 다루기가 편리하지 못하고, 구입하기도 쉽지 않다. 수중청음기 배열을 간편하게 구성하여 수중음파를 수신하는 데 사용할 목적으로 수중청음기와 데이터 로거가 일체형인 수중청음기 로거를 개발하였다. 그리고 수중청음기 로거로 구성된 수중청음기 배열 시스템을 개발하였다. 이 논문에서는 개발된 수중청음기 로거 및 수중청음기 배열 시스템의 구성에 대하여 보고한다. 또한 수중청음기 로거의 수조실험 결과 및 수중청음기 배열 시스템에 의한 해수중 주위잡음의 측정 예에 대하여 고찰한다. 그리고 이 수중청음기 배열 시스템을 사용할 때 편리한 점에 대해 기술한다. A hydrophone away is used to measure spatial distribution in underwater sound field and to detect incoming direction of sound waves in the ocean. It is not usually convenient to handle the hydrophone away because of its extensive scale. And it is not easy to purchase the hydrophone away because of expensive price. A hydrophone logger combined with a hydrophone and data logger was developed to consist conveniently of a hydrophone away for use to receive underwater sound waves. And a hydrophone array system with the hydrophone loggers was developed. Main configurations of the hydrophone 1o99er and the hydrophone array system are introduced in this paper. Also we present some measurement results by the hydrophone logger in a water tank and measurement examples on ambient noise in the sea by the hydrophone away system. And we discuss some advantages in use of the hydrophone array system.

황해에서 저주파 광대역 음원을 이용한 전달손실의 계절변동 연구

김봉채,최복경 한국음향학회 2002 韓國音響學會誌 Vol.21 No.3

해수중에서 음파는 수심, 음속구조 및 해저지질 등의 영향을 받으면서 전파한다. 특히 천해의 경우 해수중의 음속구조는 시공간적으로 심하게 변동하고 있고, 해저지질도 공간적으토 다양하게 분포한다. 황해에 있어서 저주파 음파전파의 계절변동을 조사하기 위하여 황해의 중앙부분에 위치하는 동일한 정선에서 봄철, 여름철, 가을철 등 서로 다른 계절에 저주파 광대역 음원을 이용하여 음파 전파실험을 실시하였다. 그리고 이 때에는 수중음파 전락환경을 파악하기 위하여 해수중 음속구조를 측정하였다. 이 논문에서는 황해에 있어서 음속구조 및 음파 전달손실의 측정결과에 관하여 고찰하였고, 음파 전달손실의 계절변동을 조사하였다. 그 결과 여름철에 측정된 전달손실은 봄철 및 가을철에 측정된 전달손실보다 크게 나타났고, 가을철에 측정된 전달손실은 봄철에 측정된 전달손실보다 다소 작게 나타났다. 그리고 계절에 의한 전달손실의 차이는 주파수 및 전파거리의 증가와 함께 증가하였다. The sound wave in the sea propagates under the effect of water depth, sound velocity structure, sea surface and bottom roughness, and bottom sediment distribution. In particular the sound velocity structure in shallow water varies with time and space, an? the sediment distributes very variedly with place. In order to investigate the seasonal variation of low-frequency sound propagation in the Yellow Sea, the propagation experiments were conducted along the same track in the middle part of the Yellow Sea at various seasons of spring. summer, and autumn. In this paper we consider the measurement results on the propagation loss with the sound velocity structure, and investigate the seasonal variation of the propagation loss. As a result, the propagation losses measured in summer were larger than the losses in spring and autumn. And the propagation losses measured in autumn were smaller than the losses in spring. The seasonal change of the propagation loss increased with the rise of sound frequency and the propagation range.

강우에 의하여 발생된 해수중 주위잡음의 측정

김봉채,최복경,송희천,변상경,Kim, Bong-Chae,Choi, Bok-Kyoung,Song, Hee-Chun,Byun, Sang-Kyung 한국음향학회 1994 韓國音響學會誌 Vol.13 No.1

해앙에서 강우에 의하여 발생된 수중잡음의 특성을 밝히기 위하여 한국 동해의 연안에서 비가 내리는 동안 해수중 주위잡음을 측정하였다. 수심 200 m인 정점에서 세 개의 수중청음기를 각각 수심 30 m, 50 m및 100 m에 설치하였다. 먼저 강우상도가 1.5~23.4 mm/h일 때 강우잡음의 스펙트럼 특성을 주의깊게 조사하였다. 그리고 다양한 주파수에 있어서 스펙트럼레벨과 강우강도와의 관련을 조사하였다. 또한, 수중청음기로 수신한 강우잡음의 파형을 관찰하여 강우에 의한 수중잡음의 발생기구에 대하여 고찰하였다. In order to investigate the characteristics of oceanic rain noise, we measured ambient noise at a site on the east coast of the Korean Peninsula while it rained. Three hydrophones were placed at a depth of 30 m, 50 m, and 100 m respectively where the water depth was 200 m. The spectral characteristics of rain noise were carefully examined according to rainfall rates between 1.5 and 23.4 mm/h. And the dependence of spectral level on rainfall rate was investigated for various frequencies. Also, it was considered the generation mechanism of rain noise by means of observation of rain noise waveforms received by hydrophone.

He-Ne 레이저와 CCD 카메라를 이용한 비접촉 3차원 측정

김봉채,전병철,김재도,Kim, Bong-chae,Jeon, Byung-cheol,Kim, Jae-do 대한기계학회 1997 大韓機械學會論文集A Vol.21 No.11

A fast and precise technique to measure 3-dimensional coordinates of an object is proposed. It is essential to take the 3-dimensional measurements of the object in design and inspection. Using this developed system a surface model of a complex shape can be constructed. 3-dimensional world coordinates are projected onto a camera plane by the perspective transformation, which plays an important role in this measurement system. According to the shape of the object two measuring methods are proposed. One is rotation of an object and the other is translation of measuring unit. Measuring speed depending on image processing time is obtained as 200 points per second. Measurement resolution i sexperimented by two parameters among others; the angle between the laser beam plane and the camera, and the distance between the camera and the object. As a result of these experiments, it was found that measurement resolution ranges from 0.3mm to 1.0mm. This constructed surface model could be used in manufacturing tools such as rapid prototyping machine.

자동기록식 수중청음기를 이용한 저주파 해양잡음의 측정

김봉채,김병남,조홍상 한국해양과학기술원 2007 Ocean and Polar Research Vol.29 No.4

Ocean noise may be used for monitoring wind speed and rainfall rate on the sea surface, as well as for tracking whales' migration routes. In particular, low-frequency ocean noise has recently been of concern with relation to the behavior of marine mammals. Low-frequency ocean noise has been increasing over the past few decades due to increase of ship traffic and offshore oil industry activities. Mechanical noise such as flow noise and cable strumming noise may be induced if low-frequency ocean noise is measured by cabled traditional hydrophone in high current areas. To successfully measure low-frequency ocean noise in a shallow water environment with strong current, we developed a self-recording hydrophone. This paper describes the main configurations of the self-recording hydrophone and presents some results on measured data.