• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제52권11호
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• pp.512-515
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• 2003

This paper is to investigate how partial discharge pulse signal can flow in 6.6㎸ motor stator windings. Pulse propagation is experimentally analyzed in stator windings using a variety of frequency-domain techniques. The experiments were performed on two stator windings in the laboratory. Spectrum analyzer(9KHz to 3㎓) with tracking generator(100kHz to 3㎓) was used. Sweep time of the tracking generator was looms. The frequency spectrum of the response signal was detected by active FET probe(1㎓). The active FET probe has a flat amplitude response up to 1㎓ without high frequency attenuation. The stator winding acts as a low-pass filter below 600KHz, the high-frequency components being highly declined. The resonance peaks show about 1.1MHz and 2MHz in low frequency of No. 1 and No. 2 stator windings, respectively. This low-frequency range indicates that attenuation is low. The peaks of partial discharge magnitude show about 900MHz, 1.6MHz in No. 1 stator winding and about 800KHz, 1.4MHz in No. 2 stator winding.

• International Journal of Fuzzy Logic and Intelligent Systems
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• 제9권3호
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• pp.232-237
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• 2009

Active safety vehicle devices are getting more attention recently. To prevent traffic accidents, the environment in front and even around the vehicle must be checked and monitored. In the present applications, mainly camera and radar based systems are used as sensing devices. Laser scanner, one of the sensing devices, has the advantage of obtaining accurate measurement of the distance and the geometric information about the objects in the field of view of the laser scanner. However, there is a problem that detecting object occluded by a foreground one is difficult. In this paper, criterions are proposed to manage this problem. Simulation is conducted by vehicle mounted the laser scanner and multiple-hypothesis algorithm tracks the candidate objects. We compare the running times as multi-hypothesis algorithm parameter varies.

• 한국컴퓨터정보학회지
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• 제15권1호
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• pp.179-183
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• 2007

다시점에서의 다중 객체 추적은 여러 분야에서 연구되고 있다. 다시점 영상 추적은 두 객체가 서로 근접하면 하나로 인식하는 문제점을 가지고 있다. 이러한 문제를 해결하기 위한 하나의 방법으로 능동형태모델(active shape mode: ASM)을 들 수 있다 ASM은 훈련집합을 이용하여 다른 객체에 가려진 목표 객체를 추적할 수 있다. 본 논문에서는 겹쳐진 객체를 추적하기 위해 ASM 기반의 다시점 추적 알고리듬(Multi-view tracking using ASM: MVTA)에 대해서 제안한다. 제안된 추적 방법은 (i) 영상 획득, (ii) 객체 추출, (iii) 객체 추적, 그리고 (iv) 현재 형태의 업데이트, 4가지 단계로 나눌 수 있다. 첫 번째 단계에서는 여러 대의 카메라를 사용해서 다시점 영상을 획득하며, 두 번째 단계에서는 객체를 배경으로부터 분리하며, 겹쳐진 객체로부터 목표 객체를 분리해낸다. 세 번째 단계에서는 추적을 위해 ASM을 사용하며, 마지막 단계인 네 번째 단계는 현재 입력 영상의 업데이트이다. 실험결과 제안한 MVTA는 겹쳐진 객체를 추적 시에 생기는 문제에 대해서 향상 된 결과를 보여준다.

• 반도체디스플레이기술학회지
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• 제18권1호
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• pp.97-101
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• 2019

Understanding and classification of the human's emotion play an important tasks in interacting with human and machine communication systems. This paper proposes a novel emotion recognition method by extracting facial keypoints, which is able to understand and classify the human emotion, using active Appearance Model and the proposed classification model of the facial features. The existing appearance model scheme takes an expression of variations, which is calculated by the proposed classification model according to the change of human facial expression. The proposed method classifies four basic emotions (normal, happy, sad and angry). To evaluate the performance of the proposed method, we assess the ratio of success with common datasets, and we achieve the best 93% accuracy, average 82.2% in facial emotion recognition. The results show that the proposed method effectively performed well over the emotion recognition, compared to the existing schemes.

• 한국산학기술학회논문지
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• 제8권2호
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• pp.240-244
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• 2007

본 논문에서는 실시간으로 눈을 검출하고 추적하는 새로운 방법을 제안하고자 한다. 기존의 능동적 적외선을 이용한 눈 검출 및 추적 방법은 외부의 조명에 매우 민감하게 반응하는 문제점을 가지고 있으므로, 본 논문에서는 적외선 조명을 이용한 밝은 동공 효과와 전형적인 외형을 기반으로 한 사물 인식 기술을 결합하여 외부 조명의 간섭으로 밝은 동공 효과가 나타나지 않는 경우에도 견실하게 눈을 검출하고 추적 할 수 있는 방법을 제안한다. 눈 검출과 추적을 위해 SVM과 평균 이동 추적방법을 사용하였고, 적외선 조명과 카메라를 포함한 영상 획득 장치를 구성하여 제안된 방법이 효율적으로 다양한 조명하에서 눈 검출과 추적을 할 수 있음을 보여 주었다.

• 한국소음진동공학회논문집
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• 제26권2호
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• pp.195-202
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• 2016

In this study, a concept of active sound enrichment (ASE) control system was implemented and demonstrated for improving engine sound quality inside the cabin of a passenger car during acceleration. Unlike the active noise control cancels the noise for disturbance rejection, the ASE adds additional sound to the noise for tracking control. This approach requires a new algorithm to provide additional artificial sound to the original engine sound using active control strategy to achieve a target sound profile, which is predefined to satisfy required interior sound quality. The ASE algorithm was implemented in a digital controller dSPACE DS1401 and real-time control experiment was accomplished in an actual car. The ASE control results show that the actively enriched sound of each engine order against RPM tracks the target profiles precisely and quickly and improves the discontinuity, the level ratios and the sound pressure level of each engine order. Thus it is anticipated the ASE system can be applied for the improvement of the engine sound quality inside the cabin during acceleration.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2008년도 하계종합학술대회
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• pp.925-926
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• 2008

This paper presents an object tracking method using motion vectors generated in the MPEG4 encoding process and the snake algorithm for active contours. This paper shows the possibility of realtime object tracking during MPEG4 encoding process in a conventional surveillance system. The experiments is performed on a PC platform to prove the effectiveness of the method.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2002년도 하계종합학술대회 논문집(4)
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• pp.141-144
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• 2002

This paper describes a new feature based tracking system that can track moving objects with a pan-tilt camera. We extract corner features of the scene and tracks the features using filtering, The global motion energy caused by camera movement is eliminated by finding the maximal matching position between consecutive frames using Pyramidal template matching. The region of moving object is segmented by clustering the motion trajectories and command the pan-tilt controller to follow the object such that the object will always lie at the center of the camera. The proposed system has demonstrated good performance for several video sequences.

• 한국정보통신학회논문지
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• 제7권2호
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• pp.344-352
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• 2003

본 논문에서는 CCD 카메라를 통해 전송되는 영상 시퀀스를 대상으로 움직이는 물체의 형태가 보행중인 사람, 혹은 자동차인지를 식별하고 이의 이동 방향을 판단하여, 이를 추적하는 무인 감시 시스템을 위한 효율적인 알고리즘을 제안한다. 고정 카메라 환경에서 유동적인 배경으로부터 안정된 움직임 추출을 위하여 배경과 이동 물체를 통계적 매개 변수로 모델링하고 배경만이 존재하는 초기 연속 영상 중 일부에 대하여 통계적으로 학습한다. 또한, 능동카메라 환경에서는 카메라 움직임에 의하여 배경에서도 움직임 에너지가 발생하므로 예측된 이동 궤적정보를 이용함으로써 연산량의 감소와 정확성을 기하였다. 본 논문에서 제안한 알고리즘을 고정카메라 및 능동카메라 환경에서 취득한 연속 영상에 적용한 결과 안정된 추적 결과를 얻었다. 제안한 알고리즘은 제한된 지역내의 무인 감시 시스템 도로 환경에서 교통흐름의 모니터링 시스템 및 나아가서 지능형 도로망을 위한 자가 주행 시스템에 적용이 기대된다.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2019년도 전력전자학술대회
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• pp.207-209
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• 2019

This paper proposes a grid-tied photovoltaic (PV) system, consisting of Voltage-fed dual-active-bridge (DAB) dc-dc converter with single phase inverter. The proposed converter allows a small dc-link capacitor, so that system reliability can be improved by replacing electrolytic capacitors with film capacitors. The double line frequency free maximum power point tracking (MPPT) is also realized in the proposed converter by using Ripple Correlation method. First of all, to eliminate the double line frequency ripple which influence the reduction of DC source capacitance, control is developed. Then, a designing of Current control in DQ frame is analyzed and to fulfill the international harmonics standards such as IEEE 519 and P1547, $3^{rd}$ harmonic in the grid is directly compensated by the feedforward terms generated by the PR controller with the grid current in stationary frame to achieve desire Total Harmonic Distortion (THD). 5-kW PV converter and inverter module with a small dc-link film capacitor was built in the laboratory with the proposed control and MPPT algorithm. Experimental results are given to validate the converter performance.