• 한국유체기계학회 논문집
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• 제4권4호
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• pp.22-27
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• 2001

The pump/motor selection program for optimized selection of regional water supply facilities was developed based on a flowchart compiled from basic operational data, total head requirement, initial pump/motor specification selection etc. This program was developed in Visual Basic. The program accepts, as in the flowchart, operational requirements of pumps and other system requirements, and calculates specific speed based on flow rate, total head and rotational speed. Then the calculated specific speed is used to select pump types and speed prior to determining likelihood of cavitation occurring at the calculated NPSH. Power requirement is then calculated for safe operation of pump to assist final pump selection. Test results of the program match very closely to the design values of Paldang intake pump station(3rd stage) proving that the program can be used as an effective and practical aid for designing new regional water supply systems.

• 유체기계공업학회:학술대회논문집
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• 유체기계공업학회 2001년도 유체기계 연구개발 발표회 논문집
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• pp.171-176
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• 2001

The Pump/Motor Selection Program for optimized selection of regional water supply facilities was developed based on a flowchart compiled from basic operational data, total head requirement, initial pump/motor specification selection etc.. This program was developed in Visual Basic. The program accepts, as in the flowchart, operational requirements of pumps and other system requirements and calculates specific speed based on flow rate, total head and na Then the calculated specific speed is used to select pump types and rpm Prior to determining likelihood of cavitation occurring at the calculated NPSH. Power requirement is then calculated for safe operation of pump to assist final pump selection. Test results of the program matches very closely to the design values of Paldang intake pump station(3rd stage) proving that the program can be used as an effective and practical aid for designing new regional water supply systems.

• 한국유체기계학회 논문집
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• 제14권5호
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• pp.12-17
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• 2011

The seawater lift pump system is responsible for maintaining the open canal level to provide the suction flow of circulating water pump at the set point. The objective of this paper is to design a 2-stage mixed flow pump (for seawater lifting) by inverse design method and to evaluate the overall performance and the local flow fields of the pump by using a commercial CFD code. Rotating speed of the impeller is 1,750 rpm with the flow rate of 2,700 $m^3$/h. Finite volume method with structured mesh and realized k-${\varepsilon}$ turbulent model is used to guaranty more accurate prediction of turbulent flow in the pump impeller. The numerical results such as static head, brake horse power and efficiency of the mixed flow pump are compared with the design data. The simulated results are good agreement with the design data less 3% error.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2011년 춘계학술대회논문집
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• pp.556-560
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• 2011

The seawater lift pump system is responsible for maintaining the open canal level to provide the suction flow of circulating water pump at the set point. The objective of this paper is to design a 2-stage mixed flow pump(for seawater lifting) by inverse design and to evaluate the overall performance and the local flow fields of the pump by using a commercial CFD code. Rotating speed of the impeller is 1,750 rpm with the flow rate of 2,700 $m^3/h$. Finite volume method with structured mesh and Realizable ${\kappa}-{\varepsilon}$ turbulent model is used to guaranty more accurate prediction of turbulent flow in the pump impeller. The numerical results such as static head brake horse power and efficiency of the mixed flow pump are compared with the reference data. Also, the periodic condition calculation method for the mixed flow pump was carried out in order to investigate the pump performance characteristics with the modification of impeller geometry.

• 한국해양공학회지
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• 제25권5호
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• pp.21-26
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• 2011

Seawater lift pump systems are responsible for maintaining open canal levels to provide the suction flow of circulating water pumps at the set point. The objective of this paper is to design a 2-stage mixed flow pump (for seawater lifting), investigate the new impeller modeling method, and performance improvements of the impeller by using a commercial CFD code. The rotating speed of the impeller is 1,750 rpm with a flow rate of 2,700 m3/h. A finite volume method with a structured mesh and realized k-${\varepsilon}$ turbulent model is used to guarantee a more accurate prediction of turbulent flow in the pump impeller. The performance variables such as the static head, brake horsepower, and efficiency of the mixed flow pump are compared based on changes in the impeller blade shape.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2015년도 춘계학술대회
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• pp.335-337
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• 2015

사고 준사고 선박의 경우 하인리히 법칙에 의거 사고 전 잠재적 요인을 내재하고 있는 선박이 그 예후를 미리 보이는 경우가 많다. 이러한 잠재적 요인의 집계 및 통계를 통해 사고 유발 가능선박을 분리하고, 이 선박들에 한해서는 기존의 사고 후 대책 마련 방식에서 벗어나 대형 사고를 예방하기 위한 방식으로 접근하는 것이 철저하게 필요하다고 본다. 그리하여 동해 VTS 관제 구역 내 사고 유발 가능 선박에 나타났던 잠재적 요인의 예시들과, 기존 접근 방법의 한계점에 대해 논하고, 분리된 선박에 대해 어떠한 식으로 관리할 것인지 논해보고자 한다.

• 전자통신동향분석
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• 제35권4호
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• pp.81-90
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• 2020

The use of machine learning technologies such as deep and reinforcement learning has proliferated in various domains with the advancement of deep neural network studies. To make the learning successful, both big data acquisition and fast processing are required. However, for some physical world applications such as autonomous drone flight, it is difficult to achieve efficient learning because learning with a premature A.I. is dangerous, cost-ineffective, and time-consuming. To solve these problems, simulation-based approaches can be considered. In this study, we analyze recent trends in drone simulation technologies and compare their features. Subsequently, we introduce Octopus, which is a highly precise and scalable drone simulator being developed by ETRI.

• 한국축산식품학회:학술대회논문집
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• 한국축산식품학회 2004년도 제34차 추계 국제 학술대회
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• pp.147-149
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• 2004

본 연구는 국내산 돈육의 오염도 및 병원균의 분포를 조사하기 위해 실시되었다. 가공전의 원료육과 절단 가공 후의 포장육의 병원균 오염도 비교시, 원료육 38.7% 포장육 32.3%로 원료육의 오염도가 더 높았다. 이는 비위생적인 도축시의 오염으로 추정이 가능하며 현재 의무적으로 실시하는 도축장의 HACCP 관리기준을 더욱 준수하여 위생안전성을 높여야 한다고 판단된다. 병원균에서는 L. monocytogenes의 분리율이 가장 높았으며 초기 오염이 제어되지 않을시, 저온성장균이라는 특징을 가진 증식은 L. monocytogenes 보관온도 준수만으로는 억제할 수 없다고 사료된다. 또한 축산물 취급 장소별로도 상이한 결과를 보였으며, 가장 낮은 오염 수치인 8.3%와 가장 높은 81.8%의 차이로 보아, 원료 축산물과 관련하여 취급 장소의 위생상태가 축산물의 안전성에 많은 영향을 끼친다고 사료된다.

• 한국임상수의학회지
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• 제19권2호
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• pp.207-210
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• 2002

The effects of electroacupuncture on gastric motility in dogs were investigated in this study. The acupoints used in this experiment were Zu San Li (ST-36), Feng Long (ST-40), Jie Xi (ST-41), and Li Dui (ST-45) which belong to stomach meridian, Wei Shu (BL-21) which belongs to urinary bladder meridian, and Zhong Wan (CV-12) which belongs to conception vessel meridian. The animals were stimulated with 2-4 volt and 5 Hz for 20 min. Electroacupuncture at Zu San Li and Wei Shu acupoint increased the gastric motility, but Zhong Wan decreased the motility. There were no change in gastric movement after electrostimulation at Feng Long, Jie Xi and Li Dui acupoints. It was considered that electroacupuncture at Zu San Li and Wei Shu acupoints to promote the gastric movement, and at Zhong Wan acupoint to depress the movement might be effective in veterinary practice.

• 한국임상수의학회지
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• 제19권2호
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• pp.204-206
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• 2002

The effects of electroacupuncture on small intestinal motility in dogs were investigated. The acupoints used in the experiment were Shao Ze (SI-1), Hou Xi. (SI-3), Yang Lao (SI-6), Zhi Zheng (SI-7) and Xiao Hai (SI-8) which belong to small intestine meridian, Xiao Chang Shu (BL-27) which belongs to urinary bladder meridian, and Guan Yuan (CV-4) which belongs to conception vessel meridian. The anupoints were stimulated with 2-4 volt and 5 Hz for 20 minutes Electroacupuncture at Shao Ze, Yang Lao, and Xiao Hai acupoints increased the intestinal motility, but at Guan Yuan decreased the motility. The acupuncture at Hou Xi, Zhi Zheng and Xiao Chang Shu acupoints showed an increase or decrease of the intestinal movement. The results indicate that the electroacupuncture at Guan Yuan acupoint may depress intestinal motility in cases such as vomiting or diarrhea, and the acupuncture at Shao Ze, Yang Lao, and Xiao Hai acupoints to promote the motility in cases of digestive disturbance may be effective in veterinary practice.