• 한국방재학회:학술대회논문집
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• 2007.02a
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• pp.387-390
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• 2007

The mixing characteristics of heated water discharged from different types of effluents are simulated using a commercial software, Flow-3D model. In order to verify the model, the comparison of numerical results with the experimental data are conducted for each type of effluent, the submerged and surface overfall. It is observed that the numerical results show a reasonable agreement with the experimental data. Based on this study the application to the heated water discharge problem in the field can be expected as a further study and it can be the fundamental data when determining the type of effluent in a powerplant.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.12 no.1
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• pp.36-41
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• 2002

The cause and the elimination method for the chattering phenomena were investigated in a check valve attached to the exit of an auxiliary cooling water pump in a Korean nuclear powerplant. From the site experiment and the numerical calculation, the incident angle of the disk was so small that it was not able to produce the sufficient lifting force to overcome the gravitational component of the disk weight. Moreover, it turned out that the installation position was not symmetric for the secondary vortical flow generated inside the elbow so that the flow structure had strongly unstable flow characteristics. From this study, the tapping noise and the chattering phenomena were eliminated exactly by changing the incidence angle of the valve disk and the installation position of the calve body.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2000.06a
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• pp.1848-1853
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• 2000

Cause and the elimination method for the chattering phenomena were investigated the check valve attached exit of the auxiliary cooling water pump at a korean nuclear powerplant. From the site experiment and numerical calculation the incident angle of the disk was so small that it was not able to produce the lifting force to overcome the component of disk weight. Moreover, it turned out that the installed position was not symmetric for the secondary vortical flow generated inside the elbow, so that the flow structure had strongly unstable flow characteristics. From this technical support, the tapping noise and the chattering phenomena were eliminated exactly by changing the incidence angle of the valve disk and installed position of the check valve.

• Journal of the korean Society of Automotive Engineers
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• v.4 no.2
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• pp.1-8
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• 1982

선진제국의 자동차회사들은 미래의 자동차 또는 특수차량에 이용될 수 있는 가능한 동력 원(powerplant)을 개발하기 위하여 막대한 투자와 인력을 들여 끊임없이 조사와 연구를 계속하고 있다. 이는 보다 성능이 우수한 동려원의 개발에서 비롯되며 근대에 와서는 보편적으로 자동 차에 사용되고 있는 gasoline 및 diesel연료에 의한 내연기관의 문제점(특히 공해와 석유자원의 한계 및 경제성)을 해결코저 그 연구가 다양해지고 있으며 절박한 필요성을 느끼고 있다. 이 분야에 관해 미국 GM사가 연구개발하고 있는 개략을 보면, - Unconnvertional system으로 Turbine, steam, electric, free poston 및 hybrid - Direct coeversion & muclear power system 으로 Thermoelectric power, thermionic power, electrogasdynamics, radioisotope heat source 및 nuclear rector system 등 기초과학분야로부터 응용에 이르기까지 광법위한 연구를 하고 있다. 다음에 본호에서는 unconventional system중 몇가지 project background 그 개요을 소개코저 한다.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2004.04a
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• pp.79-82
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• 2004

The rotor drive system in rotor-craft carries out power transmission from powerplant to rotors and the drive shafts are fallen into misaligned condition by the vibration of engine and shafts and the deformation of supporting structures. The high performance flexible coupling accommodates these misalignments of drive shafts. In this study, we compare the performance of the metalic flexible coupling with the composite flexible coupling through analytic method to develop the high performance flexible coupling used in the rotor drive system of UAV tilt-rotor.

• Journal of Aerospace System Engineering
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• v.6 no.2
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• pp.35-41
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• 2012

A reciprocating engine installed on a normal category airplane shall be effectively cooled by air flown through the engine compartment. A airplane powerplant designer has to design cooling air inlets, baffles, seals, and outlets to maintain cylinder head temperatures and oil temperature under the limits, and show compliance with appropriate airworthiness standard. In this study, cooling designs of the installed engine and compliance requirements applicable to the cooling designs were reviewed, and engine cooling flight test results were evaluated for design changes. Engine cooling certification test will be conducted in a next step.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 1994.11a
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• pp.59-67
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• 1994

석탄가스화 복합발전설비에 사용되는 석탄주입계통 설계/엔지니어링을 위한 체계적 방법을 제시하였다. 석탄주입계통의 주요 구성요소로는 호퍼, 필터, 스크류공급기, 공압수송기 및 사출용기등을 고려하였고, 그에 대한 설계 사양 및 제한조건들을 제시하였다. 더 나아가 석탄주입계통의 공정제어를 위해 필요한 계측장비, 제어논리 및 제어시스템에 대한 설계기준을 서술하였다. 본 연구에서 제시된 방법들은 석탄주입계통의 기본설계 또는 선정을 위한 엔지니어링에 유용하게 사용될수 있을 것으로 판단된다.

• Journal of the military operations research society of Korea
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• v.1 no.1
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• pp.131-135
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• 1975

One of the pending issues of the Ministry of Defense is the efficient management of space parts for the weapon systems. It has been known that more than 000 million dollars are needed for spare parts for the weapon systems annually. Though the problem demands a serious consideration, there has not been any systematic study on the problem as far as the author knows. One way to approach the problem is through an investigation of the system reliability under constraints. A measure of how well a system performs or meets its design objectives is provided by the concept of system reliability. If successful operation is desired for a specified period of time, reliability is defined as the probability that the system will perform satisfactorily for the required time period. This interpretation of reliability is normally applied to devices which are subject to random failures such as electrical or mechanical systems. It has been found necessary to express system reliability in terms of the reliability of the components or subsystems which comprise the system. The major subsystems of an aircraft, for example, include the electronics, powerplant, airframe and armament subsystems. Therefore, the optimal spare part kit can be found by maximizing the system reliability subject to cost or other constraints.

• Proceedings of the KSME Conference
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• 2001.11b
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• pp.735-740
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• 2001

In the nuclear power plant, emergency core coolant system(ECCS) is furnished at reactor coolant system(RCS) in order to cool down high temperature water in case of emergency. However, in this coolant system, it occurs thermal stratification phenomena in case that there is the mixing of cooling water and high temperature water due to valve leakage in ECCS. This thermal stratification phenomena raises excessive thermal stresses at pipe wall. Therefore, this phenomena causes the accident that reactor coolant flows in reactor containment in the nuclear power plant due to the deformation of pipe and thermal fatigue crack(TFC) at the pipe wall around the place that it exists. Hence, in order to fundamental identification of this phenomena, it requires the experimental research of modeling test in the pipe flow that occurs thermal stratification phenomena. So, this paper models RCS and ECCS pipe arrangement and analyzes the mechanism of thermal stratification phenomena by measuring of temperature in variance with leakage flow rate in ECCS modeled pipe and Reynold number in RCS modeled pipe. Besides, results of this experiment is compared with computational analysis which is done in advance.

• Journal of the Korean Regional Science Association
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• v.10 no.1
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• pp.89-104
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• 1994

Recently, environmental issues have remained high on the agendas of public discussion and economic research. In the case of Korea, democratic movement in the late 80's centered people's concerns on the environmental dispute according to landfill, correctional institution, crematory, and nuclear powerplant, etc., Moreover, the failure to provide these kinds of facilities in time have caused serious social problems associated with environmental protection and economic development. The purposes of this paper are threefolds. First, they organize foreign and domestic NIMBYS case studies which have been settled in a desirable way. The second concern is to analyze the consciousness of NIMBYS resident by making up a questionnaire. Third, they estimate the market values of urban unwanted facilities by employing CVM(Contingent Valuation Method) procedure. The results of the study have a double implication : that NIMBYS resident are reluctant to accept government mechanical compensation based on simple published land values, and that unique concensus to preserve the viability and healthfulness of our environment among three main bodies: residents, people, government is necessary in solving NIMBYS subjects in Korea. In addition, this first implication develops to emphasize the intrduction of releveant measures taken to reconcile NIMBYS disagreement, which are complete openness of government policies, full support of local economic development, and perfect management of pollution protection systems for NIMBYS facilities.