• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 1993년도 Proceedings of International Conference for Agricultural Machinery and Process Engineering
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• pp.1110-1116
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• 1993

A study on optimum operation performances of power efficiency, economy and exhaust emissions for a tractor was conducted. A mathematical model of multiple degree polynomial equation was applied to established the function of solid multiple parameter curves for specific fuel consumption (ge), cabon monoxide (CO) ,hydrcarbons (HC) and cabonaceous smoke (Rb). The optimum operation theorems for economy operation indicated by ge and for exhaust emissions described by Co , HC and Rb were obtained from analytical method and performance test data. The optimum operation theorems could exhibit optimum operation working points, curves, and regions. The optimum matching relations of engine speed and transmission parameters were analyzed by using computer simulation methods in accordance with the tractor specifications , actual farm working conditions in a typical drawbar pull work such as plowing , the optimum operation objective function, the ideal transmission ratio, practical gear shif ing positions and practical travel speed of the tractor TN55 medel. The results of the anlayzes indicated clearly that the optimum power efficient operation, energy saving and pollution reducing would be realized if the tractor would be operated according to theoptimum operation methods.

• 한국항해항만학회지
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• 제35권1호
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• pp.71-76
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• 2011

최근 컨테이너 터미널의 관리자들은 안벽의 생산성을 높이기 위해서 양 적하를 동시에 할 수 있는 더블 사이클이나 듀얼 사이클을 시도하고 있다. 하지만 실제 터미널의 데이터를 이용하여 듀얼 사이클을 발생시켰을 경우 YT(Yard Tractor) 배정 방법이나, QC(Quay Crane)의 작업의 속도, 야드의 수출컨테이너 위치 등에 따라 효율성이 저하될 수 있다. 특히 기존의 야드 운영방식으로는 듀얼 사이클이나 더블 사이클을 효율적으로 지원하기 어렵다. 따라서 본 논문에서는 실제 터미널에서 듀얼 사이클을 사용할 때 효율성을 더 높일 수 있는 터미널야드 운영방법을 제시한다. 모형은 시뮬레이션 분석 소프트웨어인 Arena를 이용하여 수립되었다.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2004년도 Proceedings of ISRS 2004
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• pp.336-339
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• 2004

Communication, Ocean and Meteorological Satellite (COMS) has been developed by Korean Aerospace Research Institute (KARI) since 2003. Ocean Color Imager (OCI) is the one of COMS payloads, which will monitor the marine environment around Korean peninsula routinely with the intermediate resolution. But considering COMS is to be located in the geostationary orbit, required geographical coverage is not positioned in the nadir direction of COMS but in specific location with horizontal and vertical offsets from the nadir. In this study, coverage by OCI Field Of View (FOV) is analyzed. First of all, OCI is modeled as the sensor which is a $2,500{\times}2,500$ sized 2-D CCD and the pixel resolution is about 500m. And then, OCI is simulated to be controlled to target the required coverage accurately. As a result of it, coverage by OCI FOV is determined. Finally, all coverages by OCI FOV are mapped.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.330-333
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• 2002

Even if the train of subway starts in a certain interval from the origin according to the operation plan. as the number of passenger gets increased during operation. the boarding and getting-off time will increase, and the temporary breakdown happens to the system of train during operation, causing the delay from the operation plan. this leads to the vicious circle of train operation. making the interval of train operation irregular in downtown especially. To solve this problem, we propose the method of advanced algorithm by the actual data relating to the train operation including operation time required between stations, distance between stations. capability of train, and the dwelling time, location and distance between the preceding train and next one. The central train control system adjusts the dwelling time at each station in order to recover the delayed time, and increase the operation speed at the each station. As control algorithm is applied the dwelling time and to increase the speed, the train maintains certain interval after certain amount of time passes.

• 한국유체기계학회 논문집
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• 제15권6호
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• pp.18-24
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• 2012

This study simulated the operation of a steam injected gas turbine combined heat and power (CHP) system. A full off-design analysis was carried out to examine the change in the turbine blade temperature caused by steam injection. The prediction of turbine blade temperature was performed for the operating modes suggested in the previous study where the limitation of compressor surge margin reduction was analyzed in the steam injected gas turbine. It was found that both the fully injected and partially injected operations suggested in the previous study would cause the blade temperature to exceed that of the pure CHP operation and the under-firing operation would provide too low blade temperature. An optimal operation was proposed where both the turbine inlet temperature and the injection amount were modulated to keep both the reference turbine blade temperature and the minimum compressor surge margin. The modulation was intended to maintain a stable compressor operation and turbine life. It was shown that the optimal operation would provide a larger power output than the under-firing operation and a higher efficiency than the original partially injected operation.

• 한국방재학회 논문집
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• 제4권3호
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• pp.61-72
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• 2004

본 연구에서는 퍼지제어 모형을 이용한 단일댐의 운영모형을 기포로 하여 한강수계 댐군의 연계운영 방안을 제시하였다. 단일댐 모형에 의한 댐 운영의 결과가 하류부 수위에 미치는 영향을 검토하여 모형의 홍수조절 효과를 확인하였으며 각 댐들의 제어규칙을 모의하여 하류부의 홍수조절 효과가 가장 큰 규칙을 찾음으로써 연계운영 규칙을 선정하였다. 1990, 1995년 대홍수 발생시 실제 운영실적과 연계운영의 결과를 비교한 결과 본 연구에서 개발한 모형이 각 댐의 안정성을 확보하면서 상류부 침수피해를 줄이며 하류부에서 낮은 수위을 확보할 수 있었다는 점에서 치수적인 효과가 뛰어난 운영방안이라고 판단된다.

• Archives of Plastic Surgery
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• 제37권1호
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• pp.22-25
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• 2010

Purpose: As patients who take immediate breast reconstructions with TRAM flap have increased, concomitant or delayed other elective intra-abdominal operations in these patients also have increased. There are few reports of concomitant or delayed intra-abdominal operation in TRAM flap patients. We report our experiences and outcomes of these operations which is safe and feasible. Methods: We reviewed the charts and postoperative follow-up results of 11 patients among 471 consecutive patients who took immediate breast reconstruction with TRAM flap from December of 2002 to September of 2006. Four patients took concomitant intra-abdominal operation and 7 patients took delayed intra-abdominal operation between 1 to 52 months after TRAM flap Results: There were no significant postoperative abdominal and systemic complications. One patient who took concomitant intra-abdominal operation presented partial skin necrosis of abdomen, but recovered completely with conservative treatments. Two patients took transfusion in peri-operative periods. Conclusion: Concomitant or delayed intra-abdominal operation in immediate breast reconstruction with TRAM flap could be performed safely and feasibly when it is necessary. Furthermore, it could be helpful to patients and surgeons.

• Journal of Chest Surgery
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• 제37권1호
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• pp.72-75
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• 2004

단심실성 심장기형의 교정방법으로 Fontan 수술이 행해지지만 이 수술의 위험요소를 가진 대상군에서는 고식적 수술을 시행한 후 단계적으로 Fontan 수술을 시행하는 것이 보편적이다. Fontan 수술의 시기는 고식적 수술 후 감소한 수술 위험요소와 고식적 수슬상태의 지속에 의하여 증가하는 위험 요소를 재평가한 후 결정되며, 고식술 후 비교적 조기에 시행되는 것이 보통이다. 국립의료원에서는 36세 성인 단심실증 환자에서 과거에 단방향성 Glenn 수술을 시행하고 17년 후에 완전 Fontan 수술로 전환한 증례가 있어 보고하고자 한다.

• 대한인간공학회지
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• 제7권2호
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• pp.31-44
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• 1988

If an error occurs in the automatic mode when the advanced teleoperator system performs a task in hostile environment then the automatic mode changes into the manual mode. The operation by the control program and the operation by a human recover the error in the manual mode. The system resumes the automatic mode and continues the given task. It is necessary to improve the manual mode in order to make the best use of a man-robot system, as a part of the human interface technique. Therefore, the error recovery task is performed by combining the operation by the control program representing autonomy of a robot and the operation by a human representing versatility of a human operator effectively in the view point of human factors engineering. The geometric inverse kinematics is used for the calculation of the robot joint values in the operation by the control program. The singularity operation error and the parameter operation error often occur in this procedure. These two operation errors increase the movement time of the robot and the coordinate reading time, during the error recovery task. A singularity algorithm, parameter algorithm and fuzzy control are studied so as to remove the disadvantages of geometric inverse kinematics. And the geometric straight line motion is studied so as to improve the disadvantages of the operation by a human.

• 한국수소및신에너지학회논문집
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• 제27권1호
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• pp.22-28
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• 2016

It is necessary to store and supply hydrogen isotopes for Tokamak operation. A storage and delivery system (SDS) is used for storing hydrogen isotopes as a metal hydride form. We designed and fabricated a depleted uranium (DU) bed to store hydrogen isotopes. The rapid storage of hydrogen isotopes is very important not only for safety reasons but also for the economic design and operation of the SDS. The delivery rate at the desorption temperatures without the operation of a dry pump was analyzed in comparison with that with the operation of the dry pump. The effect of the initial desorption temperatures on the dehydriding of the DU without the operation of the dry pump was measured. The effect of the initial desorption temperatures on the dehydriding of DU with the operation of the dry pump was also measured and analyzed. The primary pressure on the desorption temperatures without the operation of the dry pump was analyzed in comparison with that with the operation of the dry pump. The temperature gradient of the coil heater and the primary vessel was also analyzed. Our results will be used to develop pilot scale hydrogen isotope processes. It was confirmed that dehydriding of a medium-scale DU bed has enabled without the operation of the dry pump.