• 한국항공우주학회지
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• 제37권6호
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• pp.527-536
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• 2009

캐스케이드 실험장치에 한 개의 익형을 설치하여 캐스케이드 실험이 가능한 장치벽면의 설계를 수행하였다. 장치의 폭은 피치의 160% 넓이이다. 이 경우에 실험장치 내에 다수개의 블레이드를 설치하는 경우에 비하여 소형의 장치라도 실험의 정확성이 향상되는 장점이 있지만, 피치방향으로 주기조건을 맞추기가 어렵다. 본 연구에서는 주기조건이 얻어지도록 벽면의 형상설계를 내부유동장의 결과를 바탕으로 기울기기반과 유전자알고리즘의 방식을 사용하여 벽면을 설계하였다. 이를 위하여 목적함수는 캐스케이드 익형의 표면에서 얻어진 마하수를 적용하였으며, 실험장치의 형상 조정이 가능한 14개의 설계변수를 적용하였다. 유전자알고리즘에 의한 최적화 설계방식이 향상된 결과를 보여주었다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2011년도 춘계학술대회 논문집
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• pp.955-956
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• 2011

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 제38회 하계학술대회
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• pp.1422-1423
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• 2007

This study deals with various neural network algorithms for the on-site partial discharge pattern recognition. For the purpose, the pattern recognition has been carried out on partial discharge data for the typical artificial defect using 9 different neural network models. In order to enhance on-site applicability, artificial defects were installed in the insulation joint box of extra-high voltage xLPE cables and partial discharges were measured by use of the metal foil sensor and a HFCT as a sensor. As the result, it is found out that the accuracy of pattern recognition could be enhanced through the application of the Sigmoid function, the Momentum algorithm and the Genetic algorism on the artificial neural networks. Although Multilayer Perceptron (MLP) algorism showed the best result among 9 neural network algorisms, it is thought that more researches on others would be needed in consideration of on-site application.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 심포지엄 논문집 정보 및 제어부문
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• pp.75-76
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• 2008

In oder for the robot to walk with stability, trajectory generation method for the biped robot is important. In this paper proposed the genetic algorithm to optimize biped robot motion parameters. Because most of trajectory generation, the walking parameters determined arbitrarily. Formulating the constraints of the motion parameters, and the trajectory is derived by cubic spline function. Finally walking patterns are described through simulation studies. When the ZMP(zero moment point) and DSM(dynamic stability margin) are satisfied, the walking pattern is chosen.

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2001년도 추계학술발표대회 논문집
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• pp.183-186
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• 2001

In this paper, the analytical model to understand the propagation of electromagnetic waves in the foam core sandwich structures was proposed. Using the analytical model, efforts were made to find the optimal stacking sequence of composite skins for maximum transmittance of electromagnetic wave. Numerical analyses of unidirectional composites and foam as a function of incident angle were performed. From the results of analysis, the general tendencies of transmittance of electromagnetic wave through composites and foam were obtained. Based on the general tendencies, optimal stacking sequences of composite skins for the maximum transmittance of electromagnetic wave were found with certain ranges of incident angle using genetic algorithm(GA).

• 설비공학논문집
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• 제25권12호
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• pp.654-659
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• 2013

This paper presents a numerical optimization of louvered fins to enhance the JF factor in terms of the design parameters, including the fin pitch, the number of louvers, the louver angle, the fin thickness, and the re-direction louver length. We carried out a parametric study to select the three most important parameters affecting the JF factor, which were the fin pitch, number of louvers, and the louver angle. We optimally designed the louvered fin by using 3rd-order full factorial design, the kriging method, and a micro genetic algorithm. Consequently, the JF factor of the optimum model increased by 16% compared to that of the base model. Moreover, the optimum model reduced the pressure drop by 17% with a comparable heat transfer rate.

• 한국멀티미디어학회논문지
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• 제10권5호
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• pp.631-641
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• 2007

국내 게임시장은 MMORPG만을 생산하는 기이한 형태로 발전하고 있다. 하지만 지능형 캐릭터의 수준은 여전히 제자리걸음을 하고 있다. 본 논문에서는 유전자 알고리즘과 신경망을 사용하여 보다 뛰어난 지능을 가진 캐릭터 구현 방안을 제시하고자 한다. 또한 현재 MMORPG에서 사용되는 다른 인공지능 기술들과 비교했을 때, 그 성능이 뒤쳐지지 않음을 증명하고, 실제 MMORPG에 적용할 수 있는 구체적인 알고리즘과 구현 방법에 대해 설명한다.

• 대한조선학회논문집
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• 제45권4호
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• pp.403-410
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• 2008

This paper describes the optimization of the rudder section by the genetic algorism based on VLM(Vortex Lattice Method) and panel method. The developed propeller-rudder analysis program has been validated by comparing with experimental data. The research extends to optimize the anti-erosion rudder section of the large container ship. The object function is the amount of pressure at leading edge of rudder which is closely related with erosion phenomena. The optimized rudder has been compared with conventional rudder with NACA 0021 section by analyzing with the developed program. The finally optimized section has low and mild pressure distribution in comparison with the NACA rudder. The experiments is expected to be carried out for the validation of the present optimization and more parametric study of section geometry is also expected to be conducted in the near future.

• 제어로봇시스템학회논문지
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• 제17권10호
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• pp.1021-1028
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• 2011

The objective of this paper is to optimize the design parameters of a novel mechanism for a robotic knee orthosis. The feature of the proposed knee othosis is to drive a knee joint with independent actuation during swing and stance phases, which can allow an actuator with fast rotation to control swing motions and an actuator with high torque to control stance motions, respectively. The quadriceps device operates in five-bar links with 2-DOF motions during swing phase and is changed to six-bar links during stance phase by the contact motion to the patella device. The hamstring device operates in a slider-crank mechanism for entire gait cycle. The suggested kinematic model will allow a robotic knee orthosis to use compact and light actuators with full support during walking. However, the proposed orthosis must use additional linkages than a simple four-bar mechanism. To maximize the benefit of reducing the actuators power by using the developed kinematic design, it is necessary to minimize total weight of the device, while keeping necessary actuator performances of torques and angular velocities for support. In this paper, we use a SGA (Simple Genetic Algorithm) to minimize sum of total link lengths and motor power by reducing the weight of the novel knee orthosis. To find feasible parameters, kinematic constraints of the hamstring and quadriceps mechanisms have been applied to the algorithm. The proposed optimization scheme could reduce sum of total link lengths to half of the initial value. The proposed optimization scheme can be applied to reduce total weight of general multi-linkages while keeping necessary actuator specifications.

• Journal of Advanced Marine Engineering and Technology
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• 제37권8호
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• pp.869-876
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• 2013

본 연구에서는 초기 개발 단계에서 신속하면서도 정확한 머플러의 피로 수명을 예측하기 위하여 인공신경망을 통해서 용접부 특성을 고려한 머플러의 피로 수명을 예측하는 프로세스를 개발하였다. 머플러 피로와 파손 특성을 파악하기 위하여 굽힘 피로 시험을 수행하였다. 머플러 용접부 특성을 고려하기 위하여 인공신경망 학습 변수로 용접부 최대 응력을 선정하였으며 이를 이용하여 피로수명을 예측하였다. 인공신경망과 기존 피로 노치 계수를 이용한 피로 수명 예측 결과 비교를 통하여 인공신경망을 이용한 머플러 피로 수명 예측 방법의 타당성을 검증하였다.