• 한국군사과학기술학회지
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• 제17권4호
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• pp.456-462
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• 2014

Infrared(IR) guided heat-seeking missiles uses IR emissions from aircraft to detect and track a target. Due to passive characteristic of the IR guidance, early detection of the missile is difficult and it is significant threat to aircraft survivability. Therefore, IR signature prediction of the aircraft is an important aspect of the stealth technology. In this study, we simulated IR signature of the aircraft in real atmospheric conditions. Aircraft surface temperature distribution was calculated by using RadthermIR code. Based on temperature distribution, IR radiance and BRDF(Bidirectional Reflectance Distribution Function) image were simulated for different weather(seasonal) and background(sky/soil) conditions. The IR contrast tendencies are not aligned with surface temperature or magnitude of target IR radiance. Therefore, it is essential to simulate IR signature with various conditions and background to acquire reliable database.

• 한국농림기상학회지
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• 제8권2호
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• pp.97-106
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• 2006

Site index is an essential tool to estimate forest productivity. Generally, a site index equation is developed and used from the relationship between stand age and dominant tree heights. However, there is a limit to the use of the site index equation in the application of variable ages, environmental influence, and estimation of site index for the unstocked forest. Therefore, it has been attempted to develop a new site index equation based on various environmental factors including site, climate, and topographical variables. This study was conducted to develop a site index equation based on the relationship between site index and environmental factors for the species of Pinus koraiensis in Yangpyung-Gun, Gyunggi Province. The influence of climatic factors (temperature and solar irradiation ratio), topographical factors (elevation, slope, ratio of slope to valley and aspect) and soil profiles (soil depth by layer and soil consistency) on site index were evaluated by multiple regression analysis. Five environmental factors were selected in the final site index equation for Pinus koraiensis. The site index equation developed in this study was also verified by three evaluation statistics: model's estimation bias, model's precision, and mean square error of measurement. Based on the site index equation, the number of productive areas for Pinus koraiensis were estimated by applying GIS technique to digitized forest maps. In addition, the distribution of productive areas was compared with the areas of current distribution of Pinus koraiensis. It is expected that the results obtained in this study could provide valuable information about the amount and distribution of productive areas for Pinus koraiensis reforestation.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2000년도 추계학술대회
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• pp.262-265
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• 2000

In order to estimate spatial physicochemical properties of the spring waters in the study area, spring waters at 57 sites were investigated for measuring ten items (temperature, pH, Eh, EC, TDS, DO, salinity, alkalinity, discharge rate, and surface elevation), To compare each component with one another, regression analysis was carried out. Kriging was used to estimate the spatial characteristics and continuity of data in the study area. To solve kriging equation, the semivariogram was calculated using geostatistical software GS$^{+}$(version 3.1). As a result of semivariogram analysis, the data of nine components but surface elevation could be assumed as stationary random function, and ordinary kriging method was used for making contour maps.s.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2004년도 임시총회 및 추계학술발표회
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• pp.399-402
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• 2004

An aquifer thermal energy storage (ATES) model is simulated by FEFLOW according to the scenario of heat pump operation in two layered confining aquifer. The scenario is consisted of 4 steps: 90 days pumping (west well) and waste water injection (east well: 35 $^{\circ}C$), 90 day s stop, 90days pumping (east well) and waste water injection (west well: 5 $^{\circ}C$), and 95 days stop. The injection of the waste water is limited in the second layer and the first layer is aquitard. The temperature distribution at the surface shows low difference with reference temperature and opposit aspect with that of the second layer because the thermal transition through the first layer is very slow. Even though the simulated thermal transition in the aquifer system have a difference with real ATES system, optimal design and operate system can be developed with field tests and operational experience.

• 한국산림과학회지
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• 제95권6호
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• pp.663-671
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• 2006

본 연구는 소나무림과 참나무류림의 공간분포 패턴을 규명하기 위하여 수행하였다. 공간분석을 위한 기초 자료로 수치 임상도와 현존식생도를 활용하여 $100m{\times}100m$ 격자 단위로 전국 단위의 소나무림과 참나무류림 분포도를 제작하였다. 또한 $100m{\times}100m$ 래스터 격자 단위의 지형, 기후, 토양 관련 주제도를 제작하였다. 이상의 소나무림과 참나무류림의 분포도와 주제도간의 GIS 기반 공간 분석을 실시하여 지형, 기후, 토양 등의 환경 인자에 따른 소나무림과 참나무류림의 공간분포 특성을 분석하였으며, 이러한 공간분포 특성을 활용하여 소나무림과 참나무류림의 출현빈도모델을 제시하였다. 소나무림의 경우 참나무류림에 비하여 상대적으로 표고가 낮고 경사도가 완만하며 기온이 높은 지역에 많이 분포하고 있는 것으로 나타났다. 또한, 소나무림은 양토, 보통 이하의 얕은 토심지역이며 배수가 양호한 화성암 지역에 주로 분포한 반면, 참나무류림은 사양토, 보통 이하의 얕은 토심지역이며 배수가 양호한 변성암 지역에 주로 분포하고 있는 것으로 나타났다. 이상과 같은 지리형태학적 인자에 따른 소나무림과 참나무류림의 공간분포 패턴을 회귀식으로 도출한 결과 통계적 유의성이 매우 높게 나타났다. 본 연구 결과는 지형, 기후, 토양 등의 환경 요소를 고려한 소나무림과 참나무류림 임분의 합리적인 관리에 기여할 것으로 기대된다.

• 미생물학회지
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• 제24권2호
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• pp.184-193
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• 1986

Interrelation between environmental influences on soil microorganisms and it's effect on disease development in ginseng (Panax ginseng C.A. Meyer) field were studied to obtain a preventive measures against the root rot of ginseng caused by soil-borne pathogens in soil in three major Korean ginseng producing areas such as Kumsan, Goesan and Poonggi. Populations of actinomycetes were relatively high in fall season from September to November. Their numbers were highly populated in healthy plot in field than replanted disease field of ginseng, whereas ratio of Trichoderma spp to actinomycetes increased in healthy plot of field indicating the higher numbers of Trichoderma spp pressented in healthy plot field. The numbers of propagules of Trichoderma spp generally increased in early summer through early fall season. Their numbers were also highly populated in the healthy plot of fields. The contents of organic matter and phosphate in healthy plot of field were somewhat high, and phophate/organic matter ratio and Mg content were high in diseased replanted field. All of the soil samples showed a weak acidic pH from 4.5 to 4.7. Soilmoisture content was increased during winter season and it did not show any significant changes curing the growing period, showing 24.6% in healthy plot in field and 19.5% in deseased plot in field respectively. Soil temperature was highest in July and August and lowest in January and February.

• The Korean Journal of Ecology
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• 제6권3호
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• pp.153-166
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• 1983

The distribution of beech species (Fagus) and beech-dominated forests along climatic gradients in the Northern Hemisphere was studied by use of taxonomic and ecological literature. The genus Fagus as a whole occurs over the range of 4.5 to 20.0。C mean annual temperature and 600 to 1000 mm in lower limit, mean annual precipitation. At the higher end of the temperature range, beech occurs in zones with relatively high growing-season precipitation. Edaphically, beech species and beech-dominated forests tend to occur on mesic, moderately fertile sites. Beech-dominated forests occur in a limited portion of the climatic range of the genus with sensitive responses to other environmental factors. The distributional range of beech-dominated forests on a global scale depends more on climatic factors and geological events than on soil conditions or other factors, summarizing the facts obtained by many researchers on beech dominated forests.

• 한국수자원학회논문집
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• 제51권2호
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• pp.89-98
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• 2018

위성자료는 광범위한 지역의 변동성을 관측하기에 매우 유리하다는 특성 때문에 최근 기후변화로 인한 자연재해 등의 연구에서 각광받고 있다. 하지만 위성자료에도 여전히 시 공간적인 해상도의 한계가 있으며, 이를 극복하기 위해 다양한 센서의 융합이나 1차 산출물들을 조합하는 방법을 사용한다. 본 연구에서는 천리안 위성의 GOCI와 MI에서 관측되는 자료를 융합함으로써 500 m 공간 해상도의 지표면 온도 자료를 생산하였고, 정규 식생지수와 함께 사용하여 TVDI를 산정하였다. 산정된 TVDI를 통해 한반도의 토양수분 상태를 모니터링 하고자 하였으며, 이를 비교하기 위해 ASCAT 지표 토양수분 자료를 통해 산정된 SSMI와 비교하였다. 그 결과 천리안 TVDI와 SSMI가 대한민국 전역에서 비슷한 공간 분포를 나타냈으며, 천리안 위성을 활용하여 토양수분을 관측할 수 있는 가능성을 제시하였다. 따라서 본 연구에서 산정 된 한반도의 TVDI가 고해상도의 토양수분을 산정하는 기반이 될 수 있고, 이를 통해 천리안 위성의 활용 범위가 보다 확장되어 다양한 연구의 기반이 될 수 있을 것으로 보인다.

• 한국약용작물학회지
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• 제24권1호
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• pp.27-30
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• 2016

Background : This text was conducted to evaluate the distribution, shape characteristics and habitat condition of Crypsinus hastatus in Buyeo Korea. Methods and Results : In Buyeo, Crypsinus hastatus was distributed at an altitude of 31.2 m, a slope of 82.5% and a distance from river water of 27.2 m. The leaf blade was oblong, 2.7 cm long, 1.2 cm wide with a petiole length of 2.3 cm. The total population comprised 2,100 individuals, with the highest proportion being individuals with a leaf blade of length 0.5 - 1 cm. The temperature and light intensity of the growth point were lower, but the humidity higher, than that of growth around. The chemical properties of the soil were as follows: pH 4.42, organic matter 77.99 g/kg, electrical conductivity 0.50 dS/m, nitrate nitrogen 20.50 mg/kg and available phosphate 165.7 mg/kg. Exchangeable cation content of potassium, magnesium, sodium and calcium was 0.35, 0.70, 0.09 and $2.04cmol^+/kg$, respectively. Conclusions : In Buyeo, Crypsinus hastatus was distributed in $5.3m^2$ area of Nakhwaam, Naeseongri and Jeongamri. However, the population of the medicinal resources seemed to decrease owing to the poor environmental conditions of the habitat.

• 한국지반환경공학회 논문집
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• 제10권2호
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• pp.5-12
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• 2009

남극 세종기지 및 시베리아의 블라디보스톡에서 채취한 흙 시료에 대하여 지반공학적인 기본 시험 즉, 비중시험, 다짐시험, 입도시험, 온도변화에 따른 열전도율시험, 부동수분시험, 일축압축강도시험을 수행하였다. 또한 블라디보스톡시료에 대해 온도변화별 인장강도시험을 수행하였다. 일축압축강도시험과 인장강도 시험시 시료의 동결에 의한 부피의 팽창을 억제하면서 공시체를 만들어 온도 변화 및 함수비 변화에 따른 강도변화를 비교하였다. 열전도율 시험 결과 영하 상태에서 흙의 열전도율은 영상 상태에서의 그것보다 훨씬 높게 나타났다. 온도변화에 따른 부동수분시험 결과 부동수분은 $0{\sim}-5^{\circ}C$ 사이에서 급격히 감소하였으며, $-20^{\circ}C$까지도 부동수분이 존재하였다. 압축강도시험 결과 함수비 변화에 따라서 다양한 응력-변형률 곡선을 보였으며, 남극의 사질동결토는 동일 온도의 얼음보다 훨씬 큰 강도를 보였으나, 블라디보스톡의 점성동결토는 초기 영하상태에서는 얼음 보다 작은 강도를 보이다가 $-15^{\circ}C$ 이하에서 서서히 얼음 보다 큰 강도를 나타내기 시작하였다. 또한 온도저하에 따라 인장강도가 증가하였다.