• Journal of Astronomy and Space Sciences
• /
• v.19 no.4
• /
• pp.341-350
• /
• 2002

Near Earth Object Patrol Team (National Research Lab.) at KAO and YSTAR team at Yonsei University Observatory jointly developed a dome enclosure to be installed abroad together with a survey telescope. It has a fully-open clam shell type design to maximize the fast slew capability of the telescope and is also sturdy enough to protect the observation system under extreme weather conditions. We also developed an electric control circuit for the enclosure so that it can become a part of automated observing system. The enclosure has been installed at the Sutherland Observatory of South African Astronomical Observatory in April 2002, and has been successfully operational.

• Journal of KIISE:Computer Systems and Theory
• /
• v.29 no.2
• /
• pp.94-104
• /
• 2002

As a part of scientific data visualization automatic generation algorithms for a contour map have been investigated mainly on data which are defined at every lattice point. But in actual situation like weather data measurement. it is impossible to get data defined at every lattice point This is because the exact value on every lattice point can not be obtained due to characteristics in sampling devices or sampling methods. In order to define data on every lattice point where data were not sampled an interpolation method. was applied to the sample data to assign approximate values for some lattice type data but by using the non-lattice type of sample data sets. A triangle data link was defined by using non lattice points directly based on actually sample data set, not by using the pre-processed rectangle lattice points. The suggested algorithm generates a contour map a contour map only by using sample data set which are much smaller than old one without data interpolation and there is no skew on data any more since it does not need any interpolation to get the values of the defined lattice points.

• Proceedings of the KSRS Conference
• /
• 2006.03a
• /
• pp.178-186
• /
• 2006

기상 수치예보는 (Numerical Weather Pridiction, NWP)는 바람, 기온, 등과 같은 기상요소의 시간 변화를 나타내는 물리방정식을 컴퓨터로 풀어 미래의 대기 상태를 예상하는 과학적인 방법으로 지구를 상세한 격자 2진부호(GRIdded Binary, 이하 GRIB)로 나누어 그 격자점에서의 값으로 대기 상태를 나타낸다. 지구 각지에서의 각종 관측자료를 기초로 격자점상의 현재값을 구한다. 대용량의 격자데이터는 이진형태이어서 컴퓨터, 서버 저장장치에서 동일형태 데이터로 존재한다. 우리나라 최초의 저궤도 관측 위성인 다목적 실용위성 KOMPSAT-1호(이하, 아리랑 위성1호)는 전자광학카메라(Electro Optical Camera, EOC)를 탑재하여 1999년 12월 21일에 발사된 이후 2006년 1월 현재까지 6여년간 성공적으로 임무를 수행, 7049여회의 영상을 획득하여 국가적으로 귀중한 자료로 활용하고 있다. 아리랑 위성1호는 일일 2-3회 EOC영상을 획득하고 있으며, 임무계획(Mission Planning)은 MP(Mission Planner)가 사용자로부터 자료를 수집하여 임무분석 및 계획 서브시스템(MAPS)에 의해 계산되어진 위성의 제도예측 데이터에 촬영하고자하는 목표지점 좌표를 입력하여 자동명령생성기(KSCG)에 의해 계산된 촬영 경사각도(Tilt)값을 위성에 전송하여 목표지역의 영상을 획득하게 된다. 위성영상 획득에 있어 고가의 위성을 운영하면서 기상의 상태를 정확히 예측하여 실패없이 유효한 영상을 획득하는 것이 무엇보다 중요하다. 본 논문에서는 효율적인 위성임무계획을 위한 기상수치예보 자료를 분석하여 앞으로 발사하게 될 고해상 카메라 탑제위성인 아리랑 위성2호와 3호에 적용하고자 한다. the sufficient excess reactivity to override this poisoning must be inserted, or its concentration is decreased sufficiently when its temporary shutdown is required. As ratter of fact, these have an important influence not only on reactor safety but also on economic aspect in operation. Considering these points in this study, the shutdown process was cptimized using the Pontryagin's maximum principle so that the shutdown mirth[d was improved as to restart the reactor to its fulpower at any time, but the xenon concentration did not excess the constrained allowable value during and after shutdown, at the same time all the control actions were completed within minimum time from beginning of the shutdown.및 12.36%, $101{\sim}200$일의 경우 12.78% 및 12.44%, 201일 이상의 경우 13.17% 및 11.30%로 201일 이상의 유기의 경우에만 대조구와 삭제 구간에 유의적인(p<0.05) 차이를 나타내었다.는 담수(淡水)에서 10%o의 해수(海水)

• Proceedings of the Korea Water Resources Association Conference
• /
• 2015.05a
• /
• pp.542-542
• /
• 2015

비점오염원은 기상조건과 토지이용에 따라 시간에 따른 오염부하량의 변동폭이 크게 발생하며, 강우초기에 오염물질의 농도가 크게 나타난다. MFFn은 강우지속시간에 따라 다양하게 변화하는 오염물질의 부하량과 유출량을 특정시점에서 강우유출율과 오염물질 유출율을 계산할 수 있으며, 강우가 시작될 때 0, 종료될 때 1의 값을 나타내며, 1보다 크면 초기세척이 있음을 나타낸다. 예를 들면 MFF20에서 평균값이 2.5이면 초기우수유출수의 부피 20%에 오염물질 부하량의 부피 50%를 포함하는 것을 의미한다. 본 연구에서는 논에서의 초기세척비율 정량화하기 위해 영산강수계 논지역(이하, 학야지구)과 섬진강수계 논지역(이하, 적성지구) 각 1개유역을 선정하여 2009년부터 2012년까지 수문 및 수질 모니터링을 수행하였다. 유역면적은 학야지구는 13.69 ha 이며, 적성지구는 8.06ha 이다. 두 지역 모두 외부유입이 없으며, 배수로가 구조물화 되어 있어 관측이 용이한 지점이다. 논에서 강우시유출되는 오염물질을 산정하기 위해서 배수로 말단에 압력식 수위계와 자동채수기를 설치하여 일정간격으로 관측하였으며, 수위별 유량관측을 통해 수위-유량관계곡선식을 산정 후 유량으로 환산하였다. 채취된 수질은 수질공정시험법을 통해 BOD, COD, TOC, T-N, T-P, SS를 분석하였으며, 관측된 유량과 수질자료를 이용하여 부하량을 산정하고, MFFn을 이용하여 초기세척비율을 정량화 하였다. BOD COD, TOC, T-N, T-P, SS 의 논 초기세척비율은 n 값이 10% 때 중앙값이 각각 1.3, 1.18, 1.13, 1.2, 1.13, 1.1 였으며, 13%, 11.8%, 11.3%, 12%, 11.3%, 11% 가 유출되는 것으로 나타났으며, n 값이 20%일 때 1.3, 1.1, 1.1, 1.25, 1.2, 1.2 이였으며, 26%, 22%, 22%, 25%, 24%. 24%가 유출되는 것으로 나타났다. n 값이 30%일 때 1.25, 1.0, 1.0, 1.25, 1.13, 1.3 였으며, 37.5%, 30%, 30%, 37.5%, 33.9%, 39%가 유출되는 것으로 나타났다.

• Journal of Astronomy and Space Sciences
• /
• v.24 no.4
• /
• pp.367-378
• /
• 2007

We present a software which we developed for the multi-purpose CCD camera. This software can be used on the all 3 types of CCD - KAF-0401E ($768{\times}512$), KAF-1602E ($1536{\times}1024$), KAF-3200E ($2184{\times}1472$) made in KODAK Co.. For the efficient CCD camera control, the software is operated with two independent processes of the CCD control program and the temperature/shutter operation program. This software is designed to fully automatic operation as well as manually operation under LINUX system, and is controled by LINUX user signal procedure. We plan to use this software for all sky survey system and also night sky monitoring and sky observation. As our results, the read-out time of each CCD are about 15sec, 64sec, 134sec for KAF-0401E, KAF-1602E, KAF-3200E., because these time are limited by the data transmission speed of parallel port. For larger format CCD, the data transmission is required more high speed. we are considering this control software to one using USB port for high speed data transmission.

• 한국태양에너지학회:학술대회논문집
• /
• 2009.11a
• /
• pp.26-31
• /
• 2009

This study was analysed influence of urban higher temperature in Busan about time series analysis of AWS data. The results are as follows. (1) The temperature of Busan show min $13.2^{\circ}C$ ~max $15.8^{\circ}C$ by 50 years, it is on the rise. (2) The seasonal adjustment series, summer appeared min $17.5^{\circ}C$ ~max $28.9^{\circ}C$ with primitive series similarly. The winter was min $-11.4^{\circ}C$ ~max $17.9^{\circ}C$, the minimum temperature was more lowly than primitive series and maximum temperature was more higher than primitive series. The results, seasonal adjustment series is guessed with influence difference urban structural element beside seasonal factor. (3) Regional analytical result, January appeared with range of min 28% ~max 196% of the seasonal factor and August appeared min 90% ~ max 106%. One of the case which is of 100% or more of the seasonal factor January 12nd~17th, August appears at the 15~17th.

• Journal of Korea Water Resources Association
• /
• v.48 no.5
• /
• pp.345-355
• /
• 2015

Climate change impact on urban drainage system are analyzed in Seoul by using high-resolution climate change scenario comparing 2000s (1971~2000) with 2020s (2011~2040), 2050s (2041~2070) and 2080s (2071~2100). The historical hourly observed rainfall data were collected from KMA and the climate change scenario-based hourly rainfall data were produced by RegCM3 and Sub-BATS scheme in this study. The spatial resolution obtained from dynamic downscaling was $5{\times}5km$. The comparison of probability rainfalls between 2000s and 2080s showed that the change rates are ranged on 28~54%. In particular, the increase rates of probability rainfall were significant on 3, 6 and 24-hour rain durations. XP-SWMM model was used for analyzing the climate change impacts on urban drainage system. As the result, due to the increase of rainfall intensities, the inundated areas as a function of number of flooded manhole and overflow amounts were increasing rapidly for the 3 future periods in the selected Gongneung 1, Seocho 2, Sinrim 4 drainage systems. It can be concluded that the current drainage systems on the selected study area are vulnerable to climate change and require some reasonable climate change adaptation strategies.

• Journal of the Korean Association of Geographic Information Studies
• /
• v.4 no.1
• /
• pp.57-66
• /
• 2001

This study used four theoretical models, such as two-point linear model, linear regression model, quadratic regression model and cubic regression model which are presented from The Ministry of Science and Technology, for extraction of urban surface temperature from Landsat TM band 6 image. Through correlation and regression analysis between result of four models and AWS(automatic weather station) observation data, this study could verify spatial distribution characteristic of urban surface temperature using GIS spatial analysis method. The result of analysis for surface temperature by landcover showed that the urban and the barren land belonged to the highest surface temperature class. And there was also -0.85 correlation in the result of correlation analysis between surface temperature and NDVI. In this result, the meteorological environmental characteristics wuld be regarded as one of the important factor in urban planning.

• Korean Journal of Agricultural and Forest Meteorology
• /
• v.7 no.1
• /
• pp.107-114
• /
• 2005

Soil CO₂ emission is one of the primary components in carbon balance of terrestrial ecosystems. In soil CO₂ flux measurements, chamber method is currently the most common technique. Prior to compare or synthesize the data collected from different chamber methods, potential biases must be quantified for each measurement system. We have conducted an intercomparison experiment among four closed dynamic chamber systems and an automatic open-closed chamber system in a temperature-controlled phytotron. Due to the disturbed CO₂ concentrations inside the phytotron during the measurements with closed dynamic chambers and the changes in soil water content, the interpretation of the data was difficult to quantify the biases of individual methods. However, the experiment provided not only valuable information on the performance characteristics of the five instruments to varying soil temperature and CO₂ concentration but also useful insights for better designs and strategy for future intercomparison in a controlled environment.

• Korean Journal of Soil Science and Fertilizer
• /
• v.43 no.3
• /
• pp.374-383
• /
• 2010

Microwave radar can penetrate cloud cover regardless of weather conditions and can be used day and night. Especially a ground-based polarimetric scatterometer has advantages of monitoring crop conditions continuously with full polarization and different frequencies. Kim et al. (2009) have measured backscattering coefficients of paddy rice using L-, C-, X-band scatterometer system with full polarization and various angles during the rice growth period and have revealed the necessity of near-continuous automatic measurement to eliminate the difficulties, inaccuracy and sparseness of data acquisitions arising from manual operation of the system. In this study, we constructed an X-band automatic scatterometer system, analyzed scattering characteristics of paddy rice from X-band scatterometer data and estimated rice growth parameter using backscattering coefficients in X-band. The system was installed inside a shelter in an experimental paddy field at the National Academy of Agricultural Science (NAAS) before rice transplanting. The scatterometer system consists of X-band antennas, HP8720D vector network analyzer, RF cables and personal computer that controls frequency, polarization and data storage. This system using automatically measures fully-polarimetric backscattering coefficients of rice crop every 10 minutes. The backscattering coefficients were calculated from the measured data at a fixed incidence angle of $45^{\circ}$ and with full polarization (HH, VV, HV, VH) by applying the radar equation and compared with rice growth data such as plant height, stem number, fresh dry weight and Leaf Area Index (LAI) that were collected at the same time of each rice growth parameter. We examined the temporal behaviour of the backscattering coefficients of the rice crop at X-band during rice growth period. The HH-, VV-polarization backscattering coefficients steadily increased toward panicle initiation stage, thereafter decreased and again increased in early-September. We analyzed the relationships between backscattering coefficients in X-band and plant parameters and predicted the rice growth parameters using backscattering coefficients. It was confirmed that X-band is sensitive to grain maturity at near harvesting season.