• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2004년도 봄 학술발표회 논문집
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• pp.243-250
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• 2004

This paper reports on the evaluation of the initial stiffness of steel joints using component method as well as experimental tests. The so-called component method corresponds precisely to a simplified mechanical model composed of extensional springs and rigid links, whereby the joint is simulated by an appropriate choice of rigid and flexible components. An application to a cantilever beam-to-column steel joint is presented and compared to the experimental results obtained under cyclic loading condition. Comparison between numerical and experimental results allows to conclude that the numerical model is able to simulate, with a good level of accuracy for initial stiffness, the behaviour of beam-to-column joints.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2008년도 정기 학술대회
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• pp.380-385
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• 2008

3 DOFs model for the collision analysis of a bridge super-structure and a super-structure of the navigating vessels were proposed and analyzed. The collision event between the super-structure of vessel and the super-structure of bridge are different from the normal collision event that collided at sub-structure of bridge. Because of its moment arm, the stability force of vessel could affect to the collision behaviors. To consider this effect, 3 DOFs model including two translation DOFs and one rotational DOF were introduced. The restoration forces of the collision system were considered as nonlinear springs. The equations of motion were derived if form of differential equations and numerically solved by 4th order Runge-Kutta method. The accuracy and the feasibility of this model were verified by the numerical example with parameter of moment arm length.

• 천문학회지
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• 제38권2호
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• pp.311-314
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• 2005

We report the current status of Japanese lunar exploration SELENE (SELenological and ENgineering Explorer). As of the end of 2004, scientific instruments onboard the Main Orbiter are under final checkout before they are provided to the proto-flight-model (PFM) integration test. Also, we present the future perspectives of the lunar based instruments and facilities. 'In-situ Lunar Orientation Mea-surement (ILOM)' experiment measures the lunar rotation with high accuracy by tracking stars on the Moon with a small photo-zenith-tube type optical telescope. A basic idea of a radio telescope array of very low frequency range on the lunar far-side is also mentioned.

• 대한전기학회논문지
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• 제41권9호
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• pp.1003-1012
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• 1992

This paper presents and analysis method for designing a squirrel cage induction motor, which is aimed at analyzing the dynamic characteristics of magnetic field. This scheme is capable of estimating the effects of slot harmonics due to the rotation of rotor by utilizing Macro-airgap element combination, Voltage source treatment and Time difference algorithm. Furthermore, this strategy presents and approach which effectively compensates for end-ring of rotor. And direct convergence method is applied for considering a magnetic nonlinearity in core. In addition to the precision and the convergence study of algorithm, comparisons with experimental values prove the accuracy of this analysis method.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2002년도 춘계학술대회 논문집
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• pp.239-244
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• 2002

This study shows how the change of helix angle for different helix angle end mill affects machining accuracy. It was verified that cutting forces are remarkably low when endmill has helix angle of different helix angle $25^{\circ}\;, \; 31^{\circ}\; , \; 37^{\circ}$and AE signals have less relationship with the chance of helix angle Moreover, as the number of rotations are increased, the AE signals are increased with the proportion to the number but cutting forces are inversely proportional to the rotation.

• 한국컴퓨터산업학회논문지
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• 제8권3호
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• pp.155-166
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• 2007

본 연구에서는 얼굴 영상을 캡쳐하여 전 처리한 후 얼굴영역을 분리하고, 분리된 얼굴 영역에서 미분 연산자와 최소 형태를 세선화하여 특징을 추출하였다. Hough Transform은 $r-\theta$ 평면에서 직선의 기울기와 절편으로 변환되며, 반면 Housdorff distance는 세선화된 영상에서 선분을 추출하여 길이, 회전, 천이 특징을 추출하였다. 사람마다 다른 특징들을 추출하여 Housdorff distance과 Hough Transform에 관하여 비교분석 결과 Hough변환의 복잡도가 더 적은 것으로 판단되었다. 인식율은 Housdorff Distance를 이용한 인식율이 Hough Transformation에 비해 조금 높게 나타났다.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2005년도 Proceedings of ISRS 2005
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• pp.123-125
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• 2005

Many researchers conducted the effort for improving the classification accuracy of satellite image. Most of the study has used optical spectrum information of each pixel for image classification. By applying this method for high resolution satellite image, number of class becomes increase. This situation is remarkable for house, because the roof of house has variety of many colors. Even if the classification is carried out for many classes, roof color information of each house is not necessary. Most of the case, we need the information that object is house or not. In this study, we propose the method for detecting the object by using Genetic Algorithms (GA). Aircraft was selected as object. It is easy for this object to detect in the airport. An aircraft was taken as a template. Object image was taken from QuickBird. Target image includes an aircraft and Haneda Airport. Chromosome has four or five parameters which are composed of number of template, position (x,y), rotation angle, rate of enlarge. Good results were obtained in the experiment.

• 한국정밀공학회지
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• 제1권2호
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• pp.47-57
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• 1984

The porous matterials are used both to control the flow of the compressed gas and to serve as the bearing surface. This porous design offers several advantages over the conventional externally pressurized gas bearings. It can simplify the construction, lower the gas consumption, and make the cleaning of the gas supply less critical. Test apparatus was cinstructed to experi- mentally investigate maximum load capacity of thrust bearing was measured 200 Kg (15Kg/$\mu$m), and radial bearing was 36 Kg/$\mu$m. And a rotation accuracy of face waving was 0.0127$\mu$m, and center waving was measured 0.5 $\mu$m. Finally, the use of this method of design and manufacturing will contribute to many practical application in the field required for precision and high stability.

• 한국멀티미디어학회논문지
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• 제18권11호
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• pp.1302-1312
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• 2015

Recent research has been devoted and focused on detecting pedestrian and vehicle in intelligent vehicles except for the vulnerable road user(VRUS). In this paper suggest a new projection method which has robustness for rotation invariant and reducing dimensionality for each cell from original image to detect two-wheeler. We applied new weighting values which are calculated by maximum curvature containing very important object shape features and uniform local binary pattern to remove the noise. This paper considered the Adaboost algorithm to make a strong classification from weak classification. Experiment results show that the new approach gives higher detection accuracy than of the conventional method.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.179-181
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• 2004

This paper is proposed an adaptive fuzzy-neural network(A-FNN) controller based on the vector controlled induction motor drive system. The hybrid combination of fuzzy control and neural network will produce a powerful representation flexibility and numerical processing capability. Also, this paper is proposed speed estimation of induction motor using A closed-loop state observer. The rotor position is calculated through the stator flux position and an estimated flux value of rotation reference frame. A closed-loop state observer is implemented to compute the speed feedback signal. The results of analysis prove that the proposed control system has strong robustness to rotor parameter variation, and has good steady-state accuracy and transitory response.