• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2004년도 ICCAS
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• pp.863-868
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• 2004

Reheating furnace is an essential facility of a rod mill plant where a billet is heated to the required rolling temperature so that it can be milled to produce wire. Sometimes, it is also necessary to control a transient billet temperature pattern according to the material characteristics to prevent a wire from breaking. Though it is very important objective to obtain a correct information of a billet temperature during furnace operation. Consequently, a billet temperature profile must be estimated. In this paper, a billet heat transfer model based on FEM (Finite Element Method) with spatially distributed emission factors is proposed and a measurement is also carried out for two different furnace operation conditions. Finally, the difference between the model outputs and the measurements is minimized by using the new optimization algorithm named uDEAS(Univariate Dynamic Encoding Algorithm for Searches) with multi-step tuning strategy. Hence, the information of billet temperatures can be obtained by using proposed model on various furnace operation conditions.

• 수산해양교육연구
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• 제25권4호
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• pp.998-1007
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• 2013

At container terminals, a major measurement of productivity can be work efficiency. For improving the productivity of container crane, the more efficient container yard operation method is necessary in container terminals. Recently, container terminal operators make an experiment on the dual cycle operation, which ship loading/unloading were carried out simultaneously, for increasing the productivity of container crane. In this paper, propose a system operating efficient dual cycle methods as utilize Ad-hoc technology in distributed port operation system. The dual cycle methods that proposed recognizes position information of Y/T during an action in Ad-hoc networks in case of container transfer works by real time as load an Ad-hoc module to Y/T taking charge of a container transfer with quay and yard. Utilize Ad-hoc networks technology in an operating system of container yard, and efficiently distributed processing done Y/T to container crane compare with operation systems of the existing dedicated method, and an improvement can do an operating system of an yard.

• Journal of Chest Surgery
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• 제34권11호
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• pp.843-847
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• 2001

배경: 식도질환의 수술 후 식도재건술은 아직도 식도수술에 관여하는 외과의사에게 해결해야 될 부분이 많이 있다. 1996년 1월부터 1999년 12월가지 흉부식도암환자 27명에서 흉부식도절제술 후 15예의 식도-위 문합술과 12예의 유리총장 이식술을 시행하였다. 저자들은 식도암 수술 후 문합부 누출, 문합부위의 협착, 역류성식도염, 수술시간, 호흡기 합병증 등을 양 군을 나누어 비교하였다. 대상 및 방법: 고식적 우회술 또는 식도인공삽입술, 인두식도와 식도 위 결합부위의 암은 본 연구에서 제외하였다. 우측 개흉술로 식도를 절제하였고, 자동봉합기를 사용하여 식도-위 문합을 시행하였다. 유리공장이식술의 경우 근위부의 식도는 6예에서 자동봉합기를 사용하였으며, 6예의 근위부와 12예의 원위부는 수기통합하였다. 모든 식도 재건술은 후종격동을 경유하였다. 결과: 3예의 수술사망을 포함하여 3예의 문합부 누출, 2예의 이식공장괴사 등 중한 합병증과 11예의 역류성 식도염, 5예의 문합부 협착이 발생되었다. 식도-위 문합술의 평균 수술시간은 300$\pm$160분, 유리공장이식술은 550$\pm$280분이었다. 결론: 역류성 식도염은 식도-위 문합군에서 더 많았고, 수술시간은 유리공장이식군에서 더 길었다(p<0.05). 적절한 환자의 선택과 장시간의 수술에 따르는 술 후 합병증을 줄일 수 있다면, 식도재건수술후의 역류식도염을 감소시키는 수술로 유리공장이식술이 우수하다고 판단된다.

• Journal of Advanced Marine Engineering and Technology
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• 제24권3호
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• pp.113-120
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• 2000

On the absorber of absorption chiller/heater, LiBr solution at high concentration is sprinkled on a bundle of horizontal tube cooled by cooling water. In this case, the conditions of LiBr solution and cooling water have an influence on heat/mass transfer coefficient in this system. Therefor it is important to find optimal operation conditions of absorption chiller/heater to save energy. Heat and mass transfer coefficient increased with the increase of solution flow rate, and also heat and mass transfer rate increased but overall heat and mass transfer coefficient decreased by increasing the solution concentration within the experimental range. The superheating of the solution resulted in superior heat transfer character to a state of equilibrium from the point of heat flux and overall heat transfer coefficient.

• 한국항해항만학회지
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• 제30권3호
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• pp.235-240
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• 2006

본 연구에서는 국내에 개발예정인 자동화터미널에 적용가능한 효율적인 ATC 운영로직을 개발하기 위해서 ATC 장비 운영전략을 분석하였다. 그리고, ATC의 효율적인 운영에 있어서 가장 중요한 동적운영로직을 개발하고, 단순한 할당규칙을 수립하여 시뮬레이션 실험으로 로직검증을 하였다. 실험결과 ATC 생산성 저해요인인 간섭을 최소화하는 간섭최소화전략과 능동적인 간섭회피전략이 ATC의 대기시간 및 간섭시간을 감소시키는 것으로 나타났다. 본 연구의 결과로 ATC의 운영효율성을 향상시켜서 자동화터미널의 생산성을 향상시킬 수 있을 것으로 기대된다.

• 한국기계가공학회지
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• 제17권2호
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• pp.95-102
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• 2018

This paper presents the development of the transfer case for a 3.5-ton commercial vehicle. A transfer case is composed of many parts, including helical gear, shaft, bearing, planetary gear, and others. Helical gears are currently used as power transmitting gears due to their relatively smooth and silent operation, large load carrying capacity, and operation at higher speeds. The key parameter in transfer case development is the bending stress at the root of a tooth in the helical gear. The bending stress of the helical gear has been studied through theoretical calculation and finite element method (FEM) analysis. Major factors of the bending stress calculation are determined according to American Gear Manufacturers Association (AGMA) standards, and FEM model analysis of the helical gear is conducted. FEM results are compared with theoretical calculations and the difference of the bending stress is described.

• 수산경영론집
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• 제50권4호
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• pp.11-28
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• 2019

In this study, the Inter-Korea Fisheries Cooperation Project was divided into four categories: North Korea's Fisheries Infrastructure Development Project, Fisheries Cooperation Project, Human Exchange Project, and North Korea Fisheries Investment Project. First, North Korea's fisheries infrastructure development projects include North Korea's fisheries resource research project, it's fisheries resource development project, and joint enforcement on illegal operation of Chinese ships. Second, fisheries cooperation projects include the operation of the North-South common fish area in the West Sea, the fishing project in North Korea's East sea, and the import of North Korean seafood. Third, human exchange projects include training of aquaculture technicians in North Korea, technology transfer and training of fishing vessels, and boarding of North Korea's fisherman in Korean fishing vessels. Fourth, North Korea's fisheries investment projects include aquaculture facilities and aquaculture feed support, aquatic product processing facilities and technology transfer, and fishery equipment support. However, as international sanctions are maintained in the international community to North Korea, Inter-Korea Fisheries cooperation, however, should be promoted according to the level of easing of international sanctions as international sanctions are maintained in the international community to North Korea. First, North Korea's fisheries resource research project, North Korea's fisheries resource creation project, joint enforcement on illegal operation of Chinese ships, and operation of the common fish area in the West Sea can be promoted if international sanctions are maintained at present, promote North Korea's fisheries resource research project. Second, boarding of North Korean's fisherman in Korean fishing vessels, conducting the fishing project in North Korea's East sea, and importing North Korean seafood can be aided if commercial transactions are possible with North Korea. Third, South Korea will support aquaculture facilities and aquatic feed, fisheries processing facilities and technology transfer, fishery equipment support, training of fisheries and aquaculture technicians, fishery fishing technology transfer, and training of fisherman when a comprehensive economic cooperation project is possible with North Korea.

• 전력전자학회논문지
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• 제5권6호
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• pp.584-591
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• 2000

컴퓨터와 같은 민감한 부하를 전압강하나 정전과 같은 전원 장애로부터 보호하기 위하여 전력보상장치가 설­치되어 왔다. 전력보상장치의 경우 계통과의 연계를 위해 대부분 정지형 스위치를 이용하고 있으며, 이러한 정지형 스위치의 전환동작은 매우 중요한 부분을 차지하고 있다. 그간 전략보상장치의 구조나 제어에 관한 연구는 활발하게 진행되어 왔으나 전력보상장치의 운전을 시작하기 위한 전원 장애의 감지에 판한 연구는 매우 드문게 현실이다. 따라서 본 논문에서는 정지형 스위치 절환동작을 위해 CBEMNITIC 커브를 이용하여 컴퓨터 응용부하판 위한 새보운 전원 장애 검출 암고리즘을 제안한다. 제안된 검출 알고리즘은 동기 좌표계에서 직류 값으으 변환된 삼상 순시 전압값을 동작 기준값과 비교하는 방법을 사용하여 빠른 검출 시간을 가지도록 하였다. 그리고, 간단한 1차 디지텔 필터를 삽입하여 잡음에 강인하도록 선거하였다. 이러한 필터에 의해 나타나는 위상지연 및 이득감소를 각각 전달함수를 이용한 수식적인 해석과 오차의 정규화를 통해 보상하였다. 마지막으로 ACSL를 이용한 시뮬레이션파 실험을 통해 제안된 알고리즘의 타당성을 입증하였다.

• 한국항해항만학회지
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• 제32권6호
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• pp.465-471
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• 2008

최근 컨테이너터미널 간의 경쟁이 심화되면서 생산성 측면뿐 만 아니라 비용경제성 측면에도 관심이 부각되고 있다. 특히, 에너지 소모량 및 장비투입 규모가 큰 트랜스퍼 크레인 부문에 대한 비효율적인 작업요소가 컨테이너터미널 경쟁력 제고에 있어서 걸림돌이 되고 있으며 이에 대한 개선은 인적, 물적 운영비용의 절감과 함께 생산성의 향상에도 긍정적인 영향을 미칠 것으로 기대된다. 따라서 본 연구에서는 현재 국토해양부 주관으로 진행 중인 'RFID를 활용한 RTLS 기반 항만물류효율화 사업'을 통하여 제공 가능한 컨테이너터미널 반 출입 대상 컨테이너의 시간적 가시성을 토대의 트랜스퍼 크레인의 배정 및 이동경로에 대한 클러스터링 기반 최적화모델을 제안하고 시뮬레이션 기법을 통하여 기대효과수준을 확인하였다.

• Biotechnology and Bioprocess Engineering:BBE
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• 제9권6호
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• pp.454-458
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• 2004

A study of the POSE (predispersed solvent extraction) for succinic acid by colloidalliq­uid aphrons was conducted. The organic phase contaning TOA (tri-n-octylamine) and 1-octanol permits a selective extraction of succinic acid from its aqueous solution. There was no difference of the extractability of POSE and that of conventional mixer-settler type extraction. Taking into account the no mechanical mixing in POSE, it was concluded that the POSE process is more adaptive than the conventional mixer-settler type extraction process. From mass transfer analysis at the various concentration of TOA in counter-current continuous operation, the concentration of TOA had no influence on the mass transfer coefficient. The loading values in continuous POSE were almost same as those in batch operation.