• International Journal of Fluid Machinery and Systems
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• 제6권2호
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• pp.49-55
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• 2013

Water lubricated guide bearing was newly released and has been applied to actual hydro turbines with vertical shaft. As a result, they can have not only high bearing performance but environmental advantages in meeting the demand for reducing river pollution by oil leakage from oil lubricated guide bearing. The PTFE composite guide bearing was tested by experimental equipment operated under conditions similar to those of actual hydro turbines. Circumferential and axial tilting bearing segments help to improve the bearing performance and efficiency due to low friction loss in the bearing system. Furthermore, bearing cooling systems could be eliminated and maintenance periods could be extended, thus the initial investment and operating costs of the hydroelectric power plant are reduced.

• 소음진동
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• 제6권5호
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• pp.595-605
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• 1996

If the control force designed on the basis of the mathematical model with parameter errors is applied to control the actual system, the closed-loop performance of the actual system will be degraded depending on the degree of the errors, In this study, the effect of parameter errors on the robustness of several natural controls has been analyzed and compared. Every asymptoic stability condition for the natural controls has been derived using Lyapunov approach, and the characteristics of the stability conditions has also been compared. The extent of deviation of the closed-loop performance from the designed one for the natural controls is derived using operator techniques, and evaluated by numerical method. It has been found that the optimal control, acceleration feedback control, and acceleration-position feedback control among the considered natural controls would be robust one with respect to the parameter errors.

• 대한산업공학회지
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• 제4권2호
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• pp.59-66
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• 1978

This paper is a work scheduling for design of piping Department of chemical plant using accumulated curve. Accumulated curve prepared by analysis of performance data, collected executed manhours for chemical plant of "D" Company during the past two years. It compared scheduled manhours with actual used manhours up to six months, put into the form of figures and charts the results can he summarized as below; 1) It can he found an important factor of critical control thus piping department got 30% of total scheduled menhours. 2) A plan of manpower mobilization can be scheduled before work starting. 3) Project progress can he found easily as put into the form of figures and charts for schedule to actual.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2000년도 추계종합학술대회
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• pp.272-277
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• 2000

본 논문에서는 Self-similar 확률과 정의 및 트래픽외 특성, 그리고 최근 논문들에서 보고된 사례에 대한 동향과 실제의 데이터 트래픽 특성에 대한 분석연구를 통하여 Self-similar 패턴에 대한 연구 결과를 제시하고자 한다.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2008년도 추계학술발표대회 논문집
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• pp.273-279
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• 2008

The purpose of this study is not only to evaluate thermal performance but also to find the stress behavior of heat transfer tubes under the part load operation in Heat Recovery Steam Generator. Flow analysis was performed to know the behavior of exhaust gas from gas turbine and thermal performance was calculated using distribution of hot exhaust velocity. In addition, tubes temperature during operation were gathered from actual plant to verify the uneven flow distribution under part load operation. Stress analysis was performed using tubes temperature data gathered from actual plant under both part and full load operations to know the stress behavior of tubes.

• 설비공학논문집
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• 제19권4호
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• pp.291-298
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• 2007

The purpose of this study is to evaluate the efficacy of multizone simulation that enables to grasp of details about microbial contaminant problem in an multistoried apartment. We used actual indoor test data to figure up microbial contaminant level as initial value for the multizone simulation and estimated the various effects of indoor occupant infected with germs such as bacteria and fungus and the performance of air sterilization by using multizone simulation in substitute for infeasible experimental approach. The results show that natural ventilation make ourselves generally useful for removing indoor microbial contaminants. The results also show that the performance of air sterilization reach the maximum in the case of using mechanical ventilation and UVGI air sterilizer. The conclusion is that this multizone simulation is useful tool for actual design method for immune building systems.

• 대한전자공학회논문지
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• 제12권6호
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• pp.9-13
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• 1975

indefinite admittance matrix 회로해석법을 써서 2개의 연산증폭기를 갖는 능동 RC여파기의 합성방법을 제시하였고, 이 방법에 의하여 중심각파수와 대역폭을 독립적으로 제어할 수 있는 대역통과 능동여파기를 실현하였다. 보현된 회로에 대한 주파수특성의 이론치와 실험치는 좋은 일치를 보였다. Employing indefinite admittance matrix analysis method, a novel synthesis procedure of general active-RC filters using 2 operational amplifiers has been shown in this paper. With this procedure, a stable active-RC bandpass filter hart been designed, which provides for independent adjustment of the uning and band-width control. The predicted and actual performance is in good agreement.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2007년도 춘계학술대회 논문집
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• pp.1550-1557
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• 2007

New locomotives 8100 & series 8200, based on the BR152 of German railway are suitable for heavy-duty freight traffic as well as for passenger transport. This electric locomotive had applied by trial petition way and 57 car is operating in mainline and industrial line until now. As matter of fact, this has a purpose to help designing and manufacturing the new electric locomotive in these day when almost all the line is changing into the electric fire line. This thesis has a purpose to check whether the actual simulation value properly apply and meet the designing value, comparing the result of the simulation for the performance of developed locomotive with the result of the type test which can be proceed in actual locomotive in korea (evaluating both the design value and the performance of the real locomotive).

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 심포지엄 논문집 정보 및 제어부문
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• pp.216-218
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• 2006

The paper is proposed high performance control of induction motor drive with adaptive fuzzy logic controller(AFLC). Also, this paper is proposed speed control of induction motor using AFLC and estimation of speed using artificial neural network(ANN) controller. The back propagation neural network technique is used to provide a real time adaptive estimation of the motor speed. The error between the desired state variable and the actual one is back-propagated to adjust the rotor speed, so that the actual state variable will coincide with the desired one. The proposed control algorithm is applied to induction motor drive system controlled AFLC and ANN controller. And this paper is proposed the results to verify the effectiveness of the AFLC and ANN controller.

• 한국컴퓨터산업학회논문지
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• 제3권7호
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• pp.915-920
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• 2002

최근 몇 년 동안 몇몇 환경에서 트래픽 패턴이 Poisson 패턴보다 Self-similar 패턴에 더 가깝다는 것이 입증되어 왔다. 본 논문에서는 이러한 Self-similar 확률과정의 정의 및 트래픽의 특성, 그리고 최근 논문들에서 보고된 사례에 대해서 고찰해 봄으로써, 실제의 이동전화 데이터 트래픽 특성에 적합한지를 응용하고자 한다.