• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.83-85
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• 2003

This paper presents a speed control of permanent magnet synchronous motors (PMSM) using an adaptive integral binary observer without speed and position sensors. In view of composition with a main loop regulator and an auxiliary loop regulator, the binary observer has a property of the chattering alleviation in the constant boundary layer. In order to improve the steady state performance of the binary observer, the proposed adaptive integral binary observer is formed by adding extra integral dynamics to the switching hyperplane equation. The effectiveness of the proposed system is conformed by the experimental results.

• 정신신체의학
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• 제4권2호
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• pp.245-253
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• 1996

In spite of its prominent effects on reduction of panic attacks and preveniton of relapse, cognitive-behavioral therapy(CBT) for panic disorder is seldomly utilized and studied in this country. for the past year, authors have modified CBT program for panic disorder that was based on PCT(panic control program) designed by Dr. Barlow and Dr. Craske. Our program is composed of informational component, somatic management skills, cognitive restructuring, interoceptive exposure and in vivo exposure. One patient has significantly improved by this program and satisfied with the treatment result. The aim of this article is to present our experience of treating a panic patient with CBT.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1993년도 한국자동제어학술회의논문집(국제학술편); Seoul National University, Seoul; 20-22 Oct. 1993
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• pp.501-506
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• 1993

An efficient solution algorithm of the optimal load distribution problem with joint torque constraints is presented. Multiple robot system where each robot is rigidly grasping a common object is considered. The optimality criteria used is the sum of weighted norm of the joint torque vectors. The maximum and minimum bounds of each joint torque in arbitrary form are considered as constraints, and the solution that reduces the internal force to zero is obtained. The optimal load distribution problem is formulated as a quadratic optimization problem in R, where I is the number of robots. The general solution can be obtained using any efficient numerial method for quadratic programming, and for dual robot case, the optimal solution is given in a simple analytical form.

• Journal of the Korean Data and Information Science Society
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• 제28권5호
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• pp.1179-1189
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• 2017

In this study, we propose an alternative method for discriminant analysis using a multivariate empirical distribution function to express multivariate data as a simple one-dimensional statistic. This method turns to be the estimation process of the optimal threshold based on classification accuracy measures and an empirical distribution function of data composed of classes. This can also be visually represented on a two-dimensional plane and discussed with some measures in ROC curves, surfaces, and manifolds. In order to explore the usefulness of this method for discriminant analysis in the study, we conducted comparisons between the proposed method and the existing methods through simulations and illustrative examples. It is found that the proposed method may have better performances for some cases.

• 한국기계가공학회지
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• 제3권2호
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• pp.32-38
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• 2004

The chatter behaviour in endmilling is a complex and nonlinear phenomenon, so it is very difficult to detect and diagnose this chatter phenomenon, This paper presents new method for the detection of chatter in endmilling operation based on the wavelet transform. In this paper, the fundamental property of the wavelet transform is reviewed by comparing the spectrum of other algorithm such as FFT. This result using wavelet transform shows the possibiling of the chatter detection in endmilling operation.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2005년도 춘계학술대회논문집
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• pp.758-761
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• 2005

본 연구에서는 고속도로 발생 소음특성을 측정하여 방음벽 설계 인자를 도출하기 위함이다. 이를 위해 인터체인지 및 영업소 인접부를 포함한 총 20개소를 선정하여 소음측정을 수행하였으며, 소음원의 주파수특성 및 일일 변동특성, 노면 종류에 따른 소음발생특성, 영업소 및 인터체인지 부근에서의 소음특성을 분석하여 방음벽 설계 인자를 도출하였다.

• 한국재료학회지
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• 제13권11호
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• pp.721-724
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• 2003

A Fe-Si-B-Ni amorphous alloy manufactured by one roll melt-spinning method showed the crystallization temperature difference of a maximum $10^{\circ}C$ according to each lot. This temperature difference had a considerable influence on the annealing process to be conducted for obtaining the proper inductance of the alloy. The proper annealing temperature of the alloy was $480^{\circ}C$ and the annealing time increased as the crystallization temperature increased. The activation energy measured by Kissinger method increased as the crystallization temperature increased. Therefore, the annealing process must be adjusted by the crystallization temperature difference of the amorphous alloy.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2010년도 추계 학술발표회
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• pp.1050-1059
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• 2010

The GFRP(Glass-Fiber Reinforced Plastic) Pipe is designed to behave safely against the external forces and to secure stability of deformation and settlements in pipe, Since it is laid under the ground. In this syudy, the evaluation for stability was carried out by performing the preliminary numerical analysis to decide the sclae effect in case of indoor model test. As a result of, strain of laying pipes is preponderantly reviewed. Numerical analysis is conducted to evaluate on the field application through the comparison concerning relations between deformation and differential settlement in the GFRP and hume pipes.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2011년도 제42회 하계학술대회
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• pp.882-883
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• 2011

This paper deals with comparison on Electromagnetic losses of slotted and slotless high-speed PM Machine for Micro Turbine. Losses are consist of core losses, copper losses and eddy current losses. We are using both analytical method and 2D Finite Element Method for more detailed losses analysis. And then We compare Electromagnetic losses of slotted and slotless PM synchronous machine. This machine has designed of a generator of 800W, 400000rpm and a starter of 400W, 200000rpm.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2011년도 제42회 하계학술대회
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• pp.1208-1209
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• 2011

본 연구는 영구자석형 동기발전기의 DC-link 정전압 제어에 대하여 연구하였다. 영구자석형 동기발전기에서 발생하는 선간전압은 발전기의 회전속도에 따라 크기가 달라지기 때문에, 일반적으로 정속도 운전을 통해 정전압 출력을 한다. 그러나, 차량용 발전기의 회전자 위치검출 센서는 먼지, 온도, 진동 등에 강인한 특성을 지녀야 한다. 홀 센서를 이용한 회전자 위치 검출 알고리즘을 제안하여 발전기에 기계적인 부착이 쉽고, 사용환경에 강인하기 때문에 회전자 검출 센서로 홀 센서를 사용하고자 한다. 홀 센서는 매우 낮은 분해능을 지닌 위치 검출 방식이기 때문에, 본 논문에서는 홀센서는 낮은 분해능을 보완한 새로운 알고리즘을 제안하였다.