• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2008년도 춘계학술대회 논문집
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• pp.333-336
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• 2008

There are many different kinds of forming processes to make a tubular product such as hydroforming and tube drawing. However, we should consider a better forming process in view point of energy consumption and $CO_2$ emission to save our earth. In this paper we have conducted FEM simulations to the various forming processes for sheet and tubular products to compare their energy consumptions. One example is tubular product and the other for drawn cup. From the comparisons of total energy for hydrofroming and tube sinking processes, hydroforming is consumed more energy than tube drawing. Also the cup drawing from sheet metal and tube sinking for the cup with flange indicate that the tube sinking is better than cup drawing of sheet metal in energy consumption.

• 대한조선학회논문집
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• 제43권1호
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• pp.128-133
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• 2006

This study is focused on the skill to prevent RIB (Rigid Inflatable Boat) from sinking. For better ability to prevent sinking, single hypalon tube is replaced by double TPU (Thermoplastic Polyurethane) tube that is excellent at frictional wear strength and oil-resisting qualities. High buoyant materials are arranged in empty spaces of ship so that ship's spare buoyancy is increased. And for restoration of stable position of ship, the self-righting system is installed. Aluminium alloy is used for increasing hull strength.

• 한국항해항만학회지
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• 제35권4호
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• pp.323-334
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• 2011

Suspended and sinking particles were collected in austral summer during ODP Leg 119 to the Indian Ocean sector of the Antarctic Ocean. Field work was carried out at four sampling sites in Prydz Bay. Two of these sites were located in the Outer Bay, and two in the Inner Bay. At the four locations, a total of ten deployments of a sediment trap array were made. The concentrations of chlorophylls and their degradation products both in suspended and sinking particulate matter in Prydz Bay were analyzed using HPLC. Chlorophylls a and c were the dominant algal pigments both in suspended and sinking particles. Because of the abundance of fecal pellets at Site 740, the mean fluxes at 200 m averaged 6 fold greater than that at 50 m. This implies that a dense swarm of zooplankters, presumably large copepods and/or salps, may "feed and excrete" mainly in between 100-200 m depths at this site, closest to land in Prydz Bay. Interestingly, The flux of phaeophorbide a was generally similar in magnitude to that of chlorophyll a throughout the study areas. This is an evidence that materials escaping from near-surface regions in austral summer derive mainly from the gazing of zooplankters. "New production" from sediment-trapped CHL pigment fluxes in Prydz Bay was estimated using f-ratio of 0.15, ranging from 520 to $1,605\;{\mu}gC\;m^{-2}\;day^{-1}$.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2018년도 추계학술대회
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• pp.248-255
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• 2018

Deep-sea fishing vessel No. 501 Oryong was fully flooded through the openings and was sunk down to the bottom of sea due to the very rough sea weather on the way of evasion after fishing operation in the Bearing Sea with many crews dead and/or missed. In this study, calculation of ship stability was carried out using KST-SHIP(ship calculation system of KST), considering the effect of flow fluid and fish catch arrangement according to the progress of its sinking accident, and damage stability was analyzed. For this study, intact stability calculation of its accident ship under the full load departure condition and its calculation result were verified by comparing with each other, and intact stability according to displacement from the departure of accident ship just before the accident was calculated and analyzed. Damage stability was calculated according to the progress during sinking accident and also analyzed.

• 수산해양기술연구
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• 제43권2호
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• pp.87-100
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• 2007

This study was carried out to offer fundamental data for improving the fishing efficiency of the Danish seine. The net height and the shape in the water was measured to analyze the efficiency of the existing Danish seine. And then, an improved fishing gear was developed based on the results and was tested in the field. Measuring devices were attached on center of a ground rope and a head rope. The net height is the spread distance between the ground rope and the head rope, which was measured on the different ratio of buoyancy. The results are obtained as follows. The net height estimated from the design plan of horizontal hanging ratio 0.40 in the existing Danish seine A and B estimated both 4.94m. The net height of the existing Danish seine A and B was respectively 1.8m and 2.3m, which form 36.4% and 46.2% of the net height estimated from the design plan. Buoyancy was changed as 79.5% and 96.2% relative to the sinking force in the existing Danish seine. The net height of 79.5% was 3.95m which increased to 80% of the estimated net height. The other shows the same result with the first case. It is not necessarily that the high buoyancy/sinking force ratio make the high net height, 80% is adequate as the buoyancy/sinking force ratio. In case of the improved Danish seine, the mean net height was about 5.0m, means 58.3% of estimated net height 8.58m.

• 동의생리병리학회지
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• 제19권6호
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• pp.1673-1675
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• 2005

The pulse diagnosis is an important and universal method in Oriental medicine. Nevertheless, because of characteristic that depends on subjective sense of Oriental medicine doctor (OMD), it is not recognized by objective basis. The Korean Institute of Oriental Medicine(KIOM) and Daeyo Medi. Co. Ltd. developed the 3-D Mac using arrey piezoresistive sensors and multi-axial robot. 133 healthy subjects participated in this study, 75 males and 58 females, between 20 and 70 years of age. All subjects were relaxed in a supine position on a comfortable chair for twenty minutes before the measurement was taken. The measured position is the radial artery of subject's left wrist and the position is called Chon, Kwan and Chuck in Oriental medicine. To detect floating and sinking pulse, we established coefficient of floating and sinking(CFS). CFS means relative position of maximum pulse pressure in PH curve. The lower CFS value means that the pulse has floating tendency. There was significant diffence between CFS and diagnosis of floating-sinking pulse by OMD(p=0.020). CFS value of over 40's group was significantly larger than those of 20's and 30's(p=0.000). There was no significant difference between male and female(p=0.061).

• 한국공작기계학회논문집
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• 제10권1호
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• pp.71-77
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• 2001

Experimental study if die-sinking electrical discharge machining(EDM) was conducted with rotating electrode system including inside hole for increasing the material removal rate(MRR). With the help of dielectric fluid flow through the inside according to the different internal diameter of the hole, the molten workpiece debris could be removed and flushed out during the EDM, Cold die alloy(SKD-1) was executed for different peak current and duty factor. From this study, the MRR was found to be increased with the peak current. The more MRR was obtained for the case of electrode inside diam-eter of 10 mm, but the MRR was decreased as the diameter near at the 4mm and 6mm. The values of surface roughness and roundness were analyzed under various conditions, and these were affected by the inside diameter change of electrode.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 1999년도 춘계학술대회 논문집
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• pp.245-250
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• 1999

The experimental study of die-sinking electrical discharge machining for alloy tool steel of STD-11 with circular electrode was conducted for various conditions of the peak current and duty factor with the change of internal size of electrode for distributing the amount of dielectric flow through the electrode. From this study, the material removal rate(MRR) was found to be increased with the peak current and duty factor. The more MRR was obtained for the case of electrode inside diameter of 10mm. The surface roughness and roundness values were analyzed regularity under various conditions, and these values were not affected by the inside diameter change of electrode.

• 한국산학기술학회논문지
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• 제19권9호
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• pp.526-535
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• 2018

최근, 도서지역에서는 $CO_2$ 배출의 저감을 위하여, 디젤발전기의 가동률을 줄이고 신재생에너지전원의 비중을 높여, 계통을 안정적으로 운용할 수 있는 방안들이 연구되고 있다. 특히, Carbon free를 목표로 하는 도서지역용 Micro-grid에서는 CVCF(constant voltage & constant frequency) 인버터를 기반으로 운용되는데, CVCF 인버터용 배터리의 SOC(state of charge) 상태에 따라, 계통의 부하소비 보다 신재생에너지전원의 출력이 큰 경우에 CVCF 인버터 내에서 발생하는 에너지 Sinking에 의하여, 배터리측 전압이 급격히 상승하여, 인버터의 과전압 보호동작에 의해 CVCF 인버터가 급격하게 탈락되어 계통에 정전이 발생하는 문제점이 일어날 수 있다. 따라서, 본 논문에서는 CVCF 인버터를 기반으로 한 도서지역용 Micro-grid의 안정적인 운용을 위하여, 에너지 Sinking 시에 발생 가능한 CVCF 인버터의 탈락을 사전에 방지하는 과도상태 운용알고리즘을 제안한다. 또한, PSCAD/EMTDC의 모델링을 이용하여, 제안한 알고리즘을 적용한 Micro-grid의 과도상태 운용특성을 분석한 결과, 배터리의 전압과 SOC에 따라 CVCF 인버터가 탈락하는 과도상태를 사전에 방지할 수 있어, 본 논문의 유용성을 확인하였다.

• 한국언론정보학보
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• 제66권
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• pp.242-272
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• 2014

2010년 3월 발생한 천안함 침몰 사건과 관련하여 사건발생 원인에 대한 수많은 의혹이 있었음에도 불구하고 2010년 11월 이후 후속 탐사보도 프로그램 제작이 중단되었다. 본 연구는 탐사보도 프로그램의 생산자 연구를 통해 그 이유를 탐색했다. 탐사보도 프로그램의 제작진들을 대상으로 심층 인터뷰 분석 결과 다음 네 가지 이유를 제시했다. 첫째, 군 작전과 관련된 기밀이란 이유로 군이 정보를 독점함으로써 PD와 기자의 사실(fact) 접근이 불가능하거나 충분한 정보를 얻을 수 없었기 때문이다. 둘째, 천안함 침몰을 다룬 <추적60분>(KBS)에 대해 방송통신위원회의 '경고' 징계 등 관련 보도에 대한 탄압으로 위축효과가 일어났고, 이후 다큐멘터리 영화 <천안함 프로젝트>에 대한 상영 제한에서도 드러났듯이 국가 권력에 의한 미디어 통제가 지속됐기 때문이다. 셋째, 지상파 방송에서 자율적 제작을 주장한 제작진에 대해 이루어진 강제 인사, 조직 개편 및 국장책임제도 폐지 등으로 PD 저널리즘과 제작의 자율성이 현저하게 약화되었기 때문이다. 넷째, 방송과 사회 전반에서 나타난 "종북몰이" 현상의 확산에 따라 방송사나 제작진에게 자기검열 기제가 작동했기 때문이다. 결론적으로 탐사보도 프로그램의 구조적 주변화 환경 속에서 PD 저널리즘이 지향하는 "합리적인 의심과 검증으로 진실을 밝히기 위해 기록하는" 방송 공론장 확립을 위한 제도적 보완이 시급하다.