• Korean Journal of Remote Sensing
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• v.15 no.2
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• pp.175-181
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• 1999

A recurring eddy which located at the terminal end of the Korean East Warm Current was captured on ocean color and sea surface temperature imagery from satellite in spring and autumn. During late April, 1997 thermal infrared imagery from the NOAA AVHRR sensor and ocean color data from the Japanese ADEOS-I OCTS sensor, revealed this feature. The cold core had elevated chlorophyll concentrations, based on OCTS estimates, of greater than 3 mg/m$^3$ while the warmer surrounding waters had chlorophyll concentrations of 1 mg/m$^3$ or less. The elevated cholophyll accociated with this eddy has not been previously described. The eddy is also evident in SST images from autumn, but the SST in the core is warmer than in spring, and the warm jet flowing to the west of the eddy is also warmer is autumn compared to spring. A reccurring eddy and the high chlorophyll_a concentration area which surround around the eddy show on NOAA and SeaWiFS images in March 2, 1998. The eddy forms at the northern extent of the Korean East Warm Current as those waters collide with the cold, south-flowing Liman Current over a topographic shelf about 1500 m deep. This region of the eddy formation appears to have a strong connection with the dynamics of the western part of the polar front eddy field that dominates surface mesoscale structure in the central East (Japan) Sea. Interaction of the eddy with ARGOW tracked drifters, and evidence for its persistence are discussed.

• Aerospace Industry
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• v.16
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• pp.9-12
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• 1994

지난 4월 7일 우리 협회 주최로 섬유센터 중회의실에서 개최한 인공위성 개발의 국산화와 산업화전략 이라는 주제의 우주산업세미나에는 국내의 관련업계 및 연구기관 대표 등 많은 인사가 참석하여 성황을 이루었고 금년부터 시작되는 국산 인공위성 개발에 많은 관심을 보였다. 이에 본지는 당일 발표된 두분의 주제 가운데 항공우주연구소의 우주산업단장인 류장수 박사의 주제발표 요지를 실어 이날 참석하지 못한 여러분들의 요청에 답하기로 했다. 이하 본문에 약 한시간여에 걸친 류장수 박사의 "다목적실용위성 개발 및 국산화 계획"이라는 제하의 주제 발표 내용을 간추린 것으로 우리나라가 국가적 과제로 추진하는 위성 국산화계획을 이래하고 이에 참여를 바라는 기업들에게 많은 참고가 될 것을 기대한다.

• Korean Journal of Environment and Ecology
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• v.29 no.6
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• pp.842-849
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• 2015

This study investigated the effects of rare-earth fertilizer on the shoot cuttings' rooting of Vitex rotundifolia L. and Tamarix chinensis Lour. The shoot cutting test was carried in 2008 and the main results are summarized as follows. The rate of rooting and the average roots increased in both number and length when rare-earth fertilizer is treated in V. rotundifolia and T. chinensis in comparison to those of the untreated control plot. In particular, when rare-earth fertilizer is diluted with water 1/2500, the rooting outstandingly increases. This result is almost similar to the effect of the rooting stimulant, IAA. Although there is no differentiation in its rooting rate according to the density, the rooting of T. chinensis shows a 100 percent effect on in the entire treated plot but not in the untreated control plot, so it is usable as a rooting stimulant. As for shoot cuttings' rooting, depending on the time immersed in diluted solution of rare-earth fertilizer, both V. rotundifolia and T. chinensis showed relatively higher percentages in all treatment plot immersed for 60 minutes than for 10 minutes. In conclusion, considering the results of the rooting percentage and the average number and length of roots of V. rotundifolia and T. chinensis, the shoot cuttings' rooting appeared higher in percentage when they were immersed in the rooting stimulant for sixty minutes with a lower density than 1/2500. This result shows that rare-earth fertilizer can be utilized as an alterative for IAA rooting stimulants currently available in the market.

• Satellite Communications and Space Industry
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• v.2 no.1
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• pp.66-70
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• 1994

• Satellite Communications and Space Industry
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• v.3 no.2
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• pp.98-102
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• 1995

• Satellite Communications and Space Industry
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• v.8 no.1 s.18
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• pp.47-55
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• 2000

• The Korean Journal of Ecology
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• v.28 no.5
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• pp.327-333
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• 2005

For the first time in Korea, plant size, distribution pattern and root growth form of Tamarix chinensis were surveyed at natural stand in Shiwha Lake, from June to July in 2005. T, chinensis grew in the range of 350 m towards north-south and 270 m in east-west direction. The mean number of stems germinated from same root system was 1.9. On the stem base, the numbers of living and dead plants were 1,398 and 114, respectively. Mean perimeter and height of 1,398 plants were $5.9{\pm}3.2$ cm and $159{\pm}51$ cm, respectively. By dividing into 10 classes based on the perimeter size, the largest number of plants were included in the second smallest class category. However, by dividing into 10 classes on the bases of plant height, variation in the number of plants along the height showed normal distribution curve. The heights of dead plants were small in perimeter but diverse in height. On the root base, the number of plants was the greatest in the smallest size class, and conspicuously decreased with size increment. Distribution of T. chinensis was clumped pattern. Age of the largest plant was 8-year. T. chinensis had two types of root growth. One was horizontal growth in the periphery of soil surface, and the other vertical growth.

• Satellite Communications and Space Industry
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• v.7 no.2 s.16
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• pp.47-61
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• 1999

• Proceedings of the Korean Information Science Society Conference
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• 2001.10c
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• pp.523-525
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• 2001

방송의 패러다임의 변화에 따라 신호방식이 아날로그에서 디지털화, 소수 지상파 방송에서 다채널 방송, 단방향에서 쌍방향 등 디지털 위성방송이 사회적 이슈가 되어 가고 있다. 이에 따라 유료방송인 디지털위성방송에 대한 이해와 컨포넌트 시스템을 정의해 보고 이에 필요한 기술과 향후 가능한 디지털 위성방송 서비스 및 비즈니스를 제시 하고자 한다.

• The Bulletin of The Korean Astronomical Society
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• v.37 no.2
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• pp.184.1-184.1
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• 2012

위성은 위성의 상태제어를 위한 명령부와 해당 명령이 기능대로 수행된 것을 확인하기 위한 상태정보 획득부로 구성된다. 명령부는 위성의 버스 플랫폼에 따라서 다양한 구조 (전압, 전류, 펄스폭, 형태등)를 갖지만, 상태정보획득은 명령부에 비해서 공통적인 특성을 갖게 된다. 또한 명령부는 +17V 또는 +28V등의 고전압, 고전류의 요구조건이 필요하지만, 상태정보 획득은 아날로그용 (+15V or +12V)또는 디지털용 (+5V)로 전압과 전류조건이 명령부에 비해서 요구조건이 완화된다. 상태정보획득은 relay 상태를 획득하는 matrix 구조로된 TM matrix와 아날로그 전압 상태정보를 단일채널을 통해 획득하는 Analog 단일 채널부와 정밀한 아날로그 정보 획득을 위한 차등 Analog 채널부, 기준전압과의 비교를 통한 이진상태부와 정전류를 통한 Thermistor 상태정보 획득부로 구성이 된다. 본 논문에서는 $16{\times}8$ matrix로 구성된 TM matrix 획득부와 300채널의 단일채널 아날로그 전압 획득부, 64채널 차등 아날로그 전압획득부 및 64채널 이진상태 획득부와 16채널로 구성된 정전류 thermistor 아날로그 상태정보 획득부의 구현 방법 및 프로세서보드와의 접속을 위한 UART 접속구조등에 대한 내용과 보드 사이즈 제약사항등의 구현에 대한 개발에 대해서 평가하고자 한다.