수공냉 대류방식을 이용한 1.2kW급 LED 조명등 개발

윤병우,송종관,박장식,권홍배,Yoon, Byung-Woo,Song, Jong-Kwan,Park, Jang-Sik,Kwon, Hong-Bae 한국전자통신학회 2015 한국전자통신학회 논문지 Vol.10 No.5

As the development of high efficiency and high flux density LEDs, the trend of illumination lamp industry transfers from conventional-lamps to the LED-lamps. For energy efficiencies, LED lamps are superior to the conventional lamps, but they have heat problems. Especially, the heat problems are severe for the high luminance lamps. They degrade the soldering point of the metal PCB, and shorten the life cycle of LEDs. So, the solution of the heat sinking is very important to develop high luminance LED lamps. This study suggested a new method to solve the heat problems for high luminance LED lamps, and developed a LED lamp which has 1200W power. In this study, a water jacket is installed to the LED lamp, and the cooing water is circulated by a water pump.

넌코히어런트 전송 방식에서 초음파를 이용한 디지털 통신속도 개선 프로토콜 제안

윤병우,Yoon, Byung-Woo 한국융합신호처리학회 2009 융합신호처리학회 논문지 (JISPS) Vol.10 No.1

Propagation of electromagnetic wave in the water or underground is very difficult because of the conductivity of the propagation materials. In this case, we usually use acoustic signal as ultrasonic but, it is not easy to transfer long distance with coherent method because of time varying multipath, doppler effect, and attenuations. So, we use noncoherent method as FSK to communicate between long distances. But, as the propagation speed of acoustic sound is very slow, the BW of the channel is narrow. It is very hard to guaranty the enough speed of communication like digital image data. In this paper, we proposed a new data communication protocol which can transmit multi-bit digital data with every single ping, and improve the data communication speed in the water.

適應 補償器를 채용한 超安定性 適應 循環 필터

윤병우,신윤기,Yoon, Byung-Woo,Shin, Yoon-Ki 대한전자공학회 1990 전자공학회논문지 Vol. No.

適應 循環 필터에서 시스템 傳達 函數의 極點이 單位圓 밖으로 나감으로써 시스템이 불안정해지는 것을 방지하기 위해 適應 補償器를 채용한 適應 循環 필터 알고리듬을 제안하였고 제안한 알고리듬이 超安定性을 만족한다는 것을 證明하였다. 제안한 알고리듬 適應 雜音 除去器에 응용하여 LS방법의 適應 循環 필터를 이용한 適應 雜音 除去器, 適應 非循環 필터를 이용한 適應 雜音 除去器와의 성능을 比較하여 제안한 알고리듬의 妥當性을 立證하였다. In this paper, an adaptive Infinite Impulse Response (IIR) filter algorithm using output error method, which prevents poles of a system transfer function from being out of unit circle, is proposed, and it is proved that the proposed algorithm always satisfies hyperstability. The proposed algorithm is applied to an Adaptive Noise Canceller (ANC), and compared with a Least Square (LS) method adaptive IIR filter algorithm and an adaptive Finite Inpulse Response (FIR) filter algorithm. As a result, the validity of the proposed algorithm is proved.

등화기를 이용한 천해에서의 수중통신

윤병우,신윤기,성굉모,Yoon, Byung-Woo,Shin, Yoon-Ki,Sung, Koeng-Mo 한국음향학회 1989 韓國音響學會誌 Vol.8 No.4

수중 채널은 그 음향학적 특성상 물의 깊이, 온도 분포, 염분포 등의 환경적 특성과 수위의 경계조건, 표면 상해 등 지형적 조건들로 구성되는 시면 시스템(time varying system)으로 볼 수 있다. 특히 천해(shallow water)의 경우 물표면과 바닥이 하나의 도파관 구실을 하게되므로 multipath reflection으로 인한echo 현상이 심각하다. 따라서 천해에서의 수중 통신은, time varying multipath fading 특성의 수중 채널에 의해 왜곡된 음향 신호를 등화(equalizing)시키는 것이 수중 통신의 질을 높이는데 결정적이라 할 수 있다. 본 논문에서는 주파수 영역 적응 필터를 채택하여 Inverse modeling 기법으로 수중채널을 등화시키는 시스템을 제시하였으며 시뮬레이션으로 이들의 타당성을 조사하였다. Underwater channels can be regarded as time-varying systems in view of the acoustical characteristics due to the fact that the characteristics of the channel are affected by the environmental and geometrical conditions. Especially in shallow water case, the surface and bottom conduct as a waveguide so echo effect due tu the multipath reflections are severe. Therefore in shallow water communications, it is very important to equalize the transmitted signals distorted by the underwater channels with time-varying multipath fading. In this paper an equalizer system which employs the frequency domain adaptive filter to equalize the channels using inverse modeling technique is introduced.

편측 내경동맥 협착 환자에서의 망막 미세혈류의 변화

김남주 ( Nam Ju Kim ) , 윤병우 ( Byung Woo Yoon ) , 정흠 ( Hum Chung ) , 유형곤 ( Hyeong Gon Yu ) 대한안과학회 2003 대한안과학회지 Vol.44 No.3

SA 여파기의 차수에 따른 성능 평가

송종관,윤병우,Song, Jong-Kwan,Yoon, Byung-Woo 한국정보통신학회 2005 한국정보통신학회논문지 Vol.9 No.7

SA 여파기는 다단 여파기의 일종으로 첫째단을 이루는 부여파기의 최대 크기를 제한함으로써 여파기 성능과 구현의 복잡도를 조절할 수 있는 매우 유연한 구조를 가진다. 본 연구에서는 부 여파기의 함수(max, min, exclusive-OR, med)에 따른 성능의 변화와 잡음의 특성에 따른 성능 변화, 그리고 차수(filter order) 변화에 따른 성능 변화를 알아본다. 이를 위하여 평균 최소 자승 오차(MSE: mean squared error)를 최소화하는 최적 여파기를 설계하고, 모의실험을 통하여 각 SA 여파기 성능의 변화를 보였다. 실험 결과 여러 가지 잡음에서 여파기 설계에 관한 기초적 가이드라인을 제시하였으며, 지금까지 밝혀지지 않았던 몇 가지 새로운 사실을 밝혔다. The SA filters have a very flexible structure by limiting the maximum subwindow size. This flexible structure presents an effective trade-off between the complexity and performance of the filters. In this paper, experimental results showing the performance variation according to the change of filter order and subfilter type(such as max, min, exclusive-OR, mod) are presented. We designed optimal SA filters minimizing MSE for the various noise conditions. These results show several new properties of SA filters.

광역 화재감지를 위한 적외선 레이저 연기 검출 시스템의 설계 및 구현

박장식,송종관,윤병우,Park, Jang-Sik,Song, Jong-Kwan,Yoon, Byung-Woo 한국전자통신학회 2013 한국전자통신학회 논문지 Vol.8 No.6

In this paper, we propose a smoke detection system in order to detect a fire in a wide space, such as tunnel, airports using infra-red and visible laser. The proposed smoke detection system is composed of infra-red laser transmitter and receiver, visible laser and Zigbee wireless communication network. A visible laser is used to match transmitter and receiver and Zigbee network is utilized to propagate warnings of fire. If smoke is appeared between transmitter and receiver, received signals are decreased and it can be considered as occurring smoke. As IR laser transmitter and receiver are separated by long distance, it is difficult to match due to large variations caused by small change of direction. In this paper, it is proposed to match effectively using visible laser. When smoke is detected, warning informations are propagated by Zigbee network in the developed smoke detection system.

키넥트를 이용한 실내에서의 키 추정 방법

김성민,송종관,윤병우,박장식,Kim, Sung-Min,Song, Jong-Kwan,Yoon, Byung-Woo,Park, Jang-Sik 한국전자통신학회 2014 한국전자통신학회 논문지 Vol.9 No.3

Object recognition is one of the key technologies of the monitoring system for the prevention of crimes diversified the intelligent. The height is one of the physical information of the person, it may be important information to confirm the identity with physical characteristics of the subject has. In this paper, we provide a method of measuring the height that utilize RGB-Depth camera, the Kinect. Given that in order to measure the height of a person, and know the height of Kinect, by using the depth information of Kinect the distance to the head and foot of Kinect, estimating the height of a person. The proposed method throughout the experiment confirms that it is effective to estimate the height of a person in the room.

영상기반 보행자 키 추정 방법

김성민,송종관,윤병우,박장식,Kim, Sung-Min,Song, Jong-Kwan,Yoon, Byung-Woo,Park, Jang-Sik 한국전자통신학회 2014 한국전자통신학회 논문지 Vol.9 No.9

Object recognition is one of the key technologies of the monitoring system for the prevention of various intelligent crimes. The height is one of the physical information of a person, and it may be important information for identification of the person. In this paper, a method which can detect pedestrians from CCTV images and estimate the height of the detected objects, is proposed. In this method, GMM (Gaussian Mixture Model) method was used to separate the moving object from the background and the pedestrian was detected using the conditions such as the width-height ratio and the size of the candidate objects. The proposed method was applied to the CCTV video, and the height of the pedestrian at far-distance, middle- distance, near-distance was estimated for the same person, and the accuracy was evaluated. Experimental results showed that the proposed method can estimate the height of the pedestrian as the accuracy of 97% for the short-range, 98% for the medium-range, and more than 97% for the far-range. The image sizes for the same pedestrian are different as the position of him in the image, it is shown that the proposed algorithm can estimate the height of pedestrian for various position effectively.

선박용 변압기 없는 40W LED 조명 구동회로의 설계 및 구현

송종관,박장식,윤병우,Song, Jong-Kwan,Park, Jang-Sik,Yoon, Byung-Woo 한국전자통신학회 2012 한국전자통신학회 논문지 Vol.7 No.3

본 논문에서는 선박의 진동에 의하여 수명이 짧은 필라멘트를 사용하는 조명기구를 대체하기 위하여 선박용 LED 조명등 구동회로를 설계 및 구현하였다. 구동회로는 부피를 줄이고 비용을 절감하기 위하여 변압기가 없는 스위칭 회로로 설계되었다. 스위칭 회로는 입력 교류전압 220 V에 PWM 제어를 함으로써 안정적으로 LED를 구동할 수 있도록 설계하였다. 스위칭 회로의 펄스성 전류에 대하여 Valley-fill 방식의 역률 보상회로를 채용함으로써 역률를 개선하였다. 장기간 운항하는 선박에서의 조명등 교체 주기를 줄여 관리를 효율적으로 할 수 있도록 직병렬 배열로 LED 모듈 회로를 설계하여 LED의 일부가 손상되더라도 LED 모듈이 조명등 기능을 할 수 있도록 하였다. 개발한 구동회로를 포함한 조명기구는 전력소모와 역률이 각각 39 W, 0.925 로 선박 조명에 적합함을 확인하였다.