움직이는 관찰자용 3차원 디스플레이를 위한 두 눈의 이미지를 이용한 관찰자의 이동속도 추출

허경무,우광준,김장기 단국대학교 1999 論文集 Vol.34 No.-

In this paper, we calculate the movement velocity of viewer by using two eye images obtained at different time through the camera. This process is necessary for future 3D display technique, in which moving viewer can see 3D image continuously. We firstly extract two eyes image and calculate the pixel coordinate of center point between two eyes. Next, we calculate the movement velocity in two dimension by comparing two center point coordinates obtained at different time.

Matlab을 이용한 DC 모터의 서보 제어기 설계에 관한 연구

허경무,우광준,김장기 단국대학교 1998 論文集 Vol.33 No.-

In the paper, a design method of DC servo motor controller using Matlab is presented. The servo controller consists of velocity controller, current controller and power amplifier. The velocity control algorithm is basically PID control with appropriate filtering, and the current controller is based on PI control. Matlab control toolbox is used for easy design of servo controller, and five kinds of DC motors(50W, 100W, 200W, 300W, 500W) are used in the simulation for the control performance evaluation. The designed servo controller shows good performance up to velocity of 4500rpm. which is sufficient for the most of factory automation applications.

서보 모터 제어기의 자동 설계

허경무,우광준 단국대학교 신소재기술연구소 2000 신소재 Vol.9 No.-

본 논문에서는 DC 모터의 동특성을 고려하여 빠른 응답 특성과 속도 정밀도의 향상을 기할 수 있도록 실시간 제어를 할 수 있는 서보 제어기의 설계에 있어서, Matlab을 이용하여 자동 설계할 수 있는 소프트웨어를 개발하고, 그 알고리즘을 제시하며, 본 자동 설계 방법을 적용한 시뮬레이션 결과를 제시하고 이로부터 제어 성능이 상당히 향상되었음을 보인다. This paper deals with the development of an automatic design software for DC servo motor controller, which provides good performance in the rapid response and the velocity control accuracy. In the proposed method, the design si automatically executed using Matlab, and iterative learning control algorithms are used in the design process. We applied this method to 50W, 100W, 200W, 300W, 500W, 750W, 1.8kW and 4.5kW DC servo motor which are widely used in the industry, We compare the result of the manual tuning design method with that of the automatic design method presented in this paper. From the experimental results, we can find that the performance of the proposed method is better than that of the manual tuning design method.

움직이는 관찰자의 두 눈 위치 추적 알고리즘

허경무,김장기 단국대학교 신소재기술연구소 2000 신소재 Vol.9 No.-

본 논문에서는 움직이는 관찰자용 3차원 디스플레이를 하기 위해서, 관찰자의 움직임을 CCD카메라를 통해 정확히 위치 추적을 할 수 있는 알고리즘의 개발을 다룬다. 특히 고성능의 하드웨어 장비가 아닌, 일반적으로 사용되는 개인용 컴퓨터에서도 두 눈을 찾아내고 위치를 추적할 수 있는 알고리즘의 개발이 주 내용으로서, 개발된 알고리즘을 실제 적용한 시험 결과를 제시하여 본 방법의 두 눈 위치 추적 성능이 우수함을 밝힌다. In this paper, we suggest the methods of detecting the two eyes position of moving viewer by using images obtained through the color CCD camera. This procedure is necessary for future 3D display technique, in which the moving viewer can see the 3D image continuously.

분위기 압력이 디젤분무특성에 미치는 영향

허종철,고경남 濟州大學校 産業技術硏究所 1996 산업기술연구소논문집 Vol.7 No.1

An experimental study has been carried out to investigate the influences of injection pressure and ambient pressure on diesel spray. Especially, diesel sprays were visualized by means of double flash. The visualized spray volumes at the ambient pressure of 3MPa increase more steeply with respect to the elapsed injection time than the atomospheric pressure. The spray tip penetration is increased according to higher injection pressure and lower ambient pressure. When the ambient pressure is further increased, the transition of the spray tip penetration occurs earlier. And the spray tip velocity increases with higher injection pressure but decreases with higher ambient pressure. The spray cone angle does not vary with increasing injection time, but it depends significantly on the ambient pressure.

砂礫沓에 있어서 窒素·加里分施가 水稻의 生理的 特性에 미치는 影響

許煇,朴慶培 건국대학교 1976 論文集 Vol.4 No.1

The present experiment was carried out to see the influences of the N and K2O mixed split application on the physiological aspects of paddy rice on alluvial sandy-gravel soils. The results are summarized as follows : 1. The yield of paddy rice was increased about 22% by the N and K2O mixed split application, while the yield office was increased only 20% by the N split application and 18% by the K2O split application. 2. The split application of K2O has increased the root activities 3. The split application of N has increased contents of chlorophyll and starch in leaf blades because of higher photosynthetic activities. 4. The oxidation activity of roots by α-Naphthylamine was positively correlated with the content of chlorophyll in leaf blades. 5. The content of potassium in paddy rice plants was negatively correlated with other mineral nutrients. 6. The content of nutrient in paddy rice plants was increased by the mixed split application of N and K2O. The phenomenon considered that the mixed split application probably maintains the balance of nutrient in paddy rice plants.

디지털 시대의 소비생활변화와 소비자문제

허경옥 誠信女子大學校 生活文化硏究所 2002 生活文化硏究 Vol.16 No.-

Market environments surrounding consumers have rapidly changed. In particular. new high technology in internet and communication was rapidly diffused to greatly influence greatly variety aspects of consumer life. Changing consumers' lives are illuminated of consumers' purchasing process such as, stage of recognizing consumer needs, stage of searching consumer information, stage of purchasing consumer goods, stage of expressing consumer dissatisfaction, and stage of divestment. Given the technology in internet and communication, Consumers are able to advanced buy products and services with lower price in their convenient time by relying on electronic commerce. In addition, consumers have more chance to achieve their tastes and preferences in choosing products and goods with lower price, In sum, consumers can realize consumer sovereignty. However, there were several problems occurring in the new consumer environment including the cost problem in utilizing advanced technology, the difficulty and complexity in choosing what they want, the discrepancy of consumer information among consumers, abuse and misusage of consumer information, and consumer damages originating from purchasing, using, disposing consumer goods. Therefore, it is urgent to spend more time and energy in order to solve these problems.

Coherent 레이다용 도플러 필터 뱅크의 부엽레벨과 그 설계에 관한 연구

허경무 단국대학교 1997 論文集 Vol.31 No.-

For the enhancement of coherent radar performance, we propose two algorithms by which we can obtain a digital doppler filter bank of lower peak sidelobe level and of enhanced clutter-suppression capability and also of much flexibility in selecting the filter bank frequencies in this paper. The two proposed algorithms are the filter coefficient adjustment algorithm and the filter zero adjustment algorithm. We also analyze the increase of mainlobe bandwidth due to the decrease of peak sidelobe level and compare with other methods which use several type of windows. And we show a design scheme for the effective clutter-suppression of both ground clutters and moving clutters. By the proposed methods, it is possible to achieve higher target-detectability of coherent radar without loss of target SNR.

클러터 제거능력이 향상된 Coherent 레이다 신호처리용 저부엽 도플러 필터 뱅크 합성 알고리즘에 관한 연구

허경무 단국대학교 신소재기술연구소 1995 신소재 Vol.5 No.-

본 논문은 Coherent 레이다 도플러 프로세싱에 직접 적용할 수 있는 저부엽(Low Sidelobe) 도플러 필터 뱅크 합성 알고리즘으로서 특히 클러터 제거능력이 향상된 알고리즘을 제안하였다. 본 논문에서는 부엽 레벨(Peak sidelobe Level)을 기존 방식보다 훨씬 더 낮출수 있게 하는 동시에, 필터 간격을 임의로 선택하여 필요한 개수만큼 합성이 가능한 일반적인 알고리즘을 제안한다. 그리고 클러터 제거 능력(Clutter Suppression)에 더 큰 비중을 두어 Zero Frequency에서의 필터 응답을 0(-∞ dB)로 보장하도록 변형한 알고리즘인 클러터 제거능력 향상형 필터 뱅크 합성 알고리즘을 제시한다. 이 알고리즘은 부엽 레벨(PSL)을 원하는만큼 더 줄일수 있고 또한 각각의 부엽들의크기가 모두 같은 Equivalent Ripple Level 특성을 보장하는 뛰어난 성능 향상을 동반한다. 시뮬레이션을 통하여 알고리즘의 성능을 나타내는 설계치 접근도 및 수렴속도를 고찰해 본 결과 상당히 우수한 것으로 확인되었고, 실제 Radar 시스템에의 시험을 통해서 그 성능향상을 확인할 수 있었다. This paper concerns a low sidelobe digital doppler filter bank synthesis which enhances the clutter suppression performance of coherent pulse doppler radar and also can reduce PSL(Peak Sidelobe Level) to the desired level sufficiently. The basic idea of the algorithm is that the optimum filter coefficients are determined through the iterative adjustment of the zeroes of the filter transfer function until the desired performance is obtained. the simulation shows that the proposed algorithm has an excellent clutter suppression capability and 춤 reduce PSL even to-120dB without a great increase in mainlobe bandwidth. It also shows that the proposed algorithm has the Equivalent Ripple Level characteristics.

柑橘屬植物의 成分分類學的 硏究

許仁玉,高京秀 제주대학교 1990 논문집 Vol.30 No.-

25th Citrus species and 3rd other species were studied on the composition of their Flavonoid compounds to identify relatonships, their taxonmical position and strain of native Citrus. These plant were groued into 5 alliences based on the quantitative analysis Flavonoids by HPLC, which were nearly identical to the subgenus rank by Tanaka and Huh. The Flavonoid patterns of HPLC are classified into 5 allience closely related to their mophological system.