• Proceedings of the Korea Water Resources Association Conference
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• 2022.05a
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• pp.107-107
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• 2022

소하천의 홍수 예측은 대부분 수치모형을 직접 활용하거나, 미리 설정된 시나리오에 기반하여 수치모의를 수행하고 계산된 결과를 이용하여 추정한 경험식을 활용한다. 수치모형과 그 결과를 홍수 예·경보에 활용하기 위해서는 계측자료에 기반하여 변수를 최적화하는 등의 수치모형 검증절차가 매우 중요하다. 소하천은 국가, 지방하천에 비해 계측자료가 절대적으로 부족한 형편으로 소하천의 홍수 모의를 위해서 주로 국가, 지방하천에서 계측한 자료를 이용하여 검증을 수행한다. 이렇게 검증된 소하천 수치모형은 국가 혹은 지방하천 유역 전체를 모의하여야 하므로 모의시간이 많이 소요되어 1시간내에 홍수유출이 이루어지는 소하천 홍수 모의에는 적절치 않다. 또한 소하천은 하천경사가 급하고 유속이 빨라 실시간 홍수모의가 어려울 수 있다. 따라서 소하천의 홍수 예측방법으로 수치모형 보다는 계측자료에 기반한 추정삭이 보다 더 효율적이다. 행정안전부와 국립재난안전연구원은 2017년부터 소하천 홍수 예측기술 개발을 위하여 자동유량계측기술을 소하천에 확대적용하고 실시간 수리량 자료를 계측하고 있다. 자동유량계측기술은 CCTV를 이용하여 표면유속을 구하고 동시에 계측된 수위와 단면자료를 이용하여 자동으로 유량을 계측하는 기술이다. 자동유량계측기술은 저비용, 저노동, 고효율의 유량계측기술로써 부족한 계측인력과 계측의 안전성을 고려할 때 소하천에 적합한 계측기솔이라고 할 수 있다. 행정안전부와 국립재난안전연구원은 2025년 까지 전국 소하천의 10%인 2,230개 소하천에 자동유량계측기술을 확대 구축하고 실시간으로 수리량 자료를 걔측할 계획이다. 본 연구에서는 이들 계측자료와 AI 등 첨단기술에 기반한 홍수 예측기술 개발하고자 한다. 예측기술은 계측유역과 미계측유역을 구분하며, 계측유역에 대해서는 계측자료를 이용하고 미계측 유역에 대해서는 단위도법과 CES를 이용하여 구한 결과를 이용하여 강우-유량 노모그래프와 수위-유량 관계식을 개발한다. 이때 노모그래프는 토양수분조건을 고려하여 개발하며, 미계측 소하천의 예측결과는 소하천을 그룹화하고 동일 그룹내에 포함된 소하천의 계측자료를 이용하여 검증한다. 개발된 홍수 예측기술은 소하천 홍수 예·경보시스템에 적용되며 이렇게 개발된 시스템은 소하천의 인명피해 저감에 크게 기여할 수 있을 것으로 기대된다.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.48 no.6
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• pp.506-515
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• 2003

Six barley varieties that showed different degree of drought tolerance were grown with and without drought stress treatment (control), and investigated for the temporal changes in growth and several physiological traits after drought treatment. Soil water potential was -0.05 ㎫ at the initial stage of drought treatment and dropped to -0.29 ㎫ at 19 days after withholding irrigation. Soil water potential (SWP) maintained at -0.05 ㎫ in the control. The dry weight (DW) under the drought treatment were reduced compared to the control as follows: Dicktoo-S (short awn), 69% ; Dicktoo-L (long awn), 70%; Dicktoo-T (tetra), 86%; Dongbori-1, 69%; Suwonssalbori-365, 55% and Tapgolbori, ,37%. Dicktoo lines and Dongbori-1 were more tolerant than Suwonssalbori-365 and Tapgolbori. Leaf relative water contents (RWC) and leaf water potential (LWP) decreased obviously under the drought condition, the decrease being greater especially in the less drought-tolerant barley genotypes. Dongbori-1 and Dicktoo-L in drought treatment showed net photosynthesis of 38% and 17% compared to the control, respectively, and the other four genotypes much lower photosynthesis of 1.1% to 7.0%. Stomatal conductance, mesophyll conductance, and the photochemical efficiency (Fv/Fm) of PS II were reduced by drought treatment, the reduction being greater in drought-sensitive genotypes. The drought-tolerant genotypes had greater osmotic adjustment (OA) capacity under water stress. Thus, the decrease of RWC and LWP was lower and the turgor pressure conservation capacity was higher under water stress in drought-tolerant genotypes. Drought-tolerant genotypes showed less decrease of photosynthesis because stomatal conductance, mesophyll conductance and the ratio (Fv/Fm) of the variable to maximal fluorescence of drought-resistant genotype was decreased less in the drought stress condition. In conclusion, the drought-tolerant genotypes had better water conservation capacity through efficient OA, and this led to the lower decrease of photosynthesis and growth in water stress condition.

• Horticultural Science & Technology
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• v.17 no.2
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• pp.115-117
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• 1999

Tomato (Lycopersicon esculentum) fruits were grown by the hydroponic cultivation system using perlite and soil cultivation system. The growth, yield, and fruit quality were compared between two growing seasons of spring and summer and two cultivation systems, respectively. In tomato, little difference was observed in growth and yield between two cultivation systems, but plant growth and total yield of fruits were much more in summer than in spring. The contents of glucose and fructose were more in spring-grown fruit than in summer-grown one, and in hydroponically cultivated fruit than in soilcultivated, respectively. The weight loss during room temperature storage was lower in hydroponically cultivated fruit than in soil-cultivated one, and in summer-grown fruit than in spring-grown one, respectively. In terms of color change, the shelf-life of tomato fruit was shorter by one day in summer-grown one fruit than in spring-grown one, and in hydroponcically cultivated one fruit than in soil-cultivated, respectively.

• Journal of Climate Change Research
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• v.4 no.3
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• pp.255-267
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• 2013

This study aims to reveal the relationship between major climatic factors and radial growth in Siu-ri, NamYangJuSi, Kyeonggido. To identify tree growth responses to climatic variation, we used correlation analysis after standardization and cross-dating of tree ring growth. We use the climatic data(monthly mean, minimum, maximum temperature and precipitation) from September of previous year to August of current year. In terms of relationship between mean, minimum, maximum temperature and tree ring growth, negative correlations were observed in September and October of the previous year. In case of Quercus mongolica, negative relationship were appeared in December of the previous year, January and February of present year. When it comes monthly maximum temperature, August and September of present year was negatively correlated with radial growth in the case of Pinus densiflora. We can conclude that reduced soil moisture due to high temperatures causes a water stress that stunts tree growth. In contrast, there are positive correlations in March of present year. These results suggest that high temperatures in March appear to prolong the growing season. Growth was positively correlated with precipitation from October to December of previous year and from May to September of present year. The results suggest that the smooth water supply from precipitation can promote the tree growth.

• Korean Journal of Heritage: History & Science
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• v.48 no.4
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• pp.62-73
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• 2015

The Tae-Jo Geonwolleung is the tomb of the first king Tae-Jo of the Joseon Dynasty in the complex of the Royal Tombs of the Joseon Dynasty which is listed in World Heritage, and it contains various types of stone properties. The material of the stone properties consist of a single type of medium-grained biotite granite, however, each properties have different intensity and types in deterioration phenomena according to their locations and purposes. The major deterioration types of the stones are analyzed as physical decomposition and biodeterioration. The exfoliation, breaking-out and granular decomposition are widespread types of the deterioration throughout the entire burial mound stone properties and surrounding stone properties. On the other hands, the colonization of mosses and plants, and contamination by foreign materials are found more frequent in the burial mound stone properties as these stones are in contact with the soil of the tomb mound and moisture in the soil helped biodeterioration. It is suggested that anti-biology treatment and physical reinforcement are applied to the deteriorated stones to prevent further damage on the stone components of the tomb.

• Korean Journal of Environmental Agriculture
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• v.30 no.2
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• pp.160-165
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• 2011

BACKGROUND: This study carried out to fate of pesticide and investigate worker exposure of pesticide in air after applying granular type pesticide formulation on soil in greenhouse for preventing farmer's pesticide intoxication. METHODS AND RESULTS: The recovery of pesticide, cadusafos, ethoprophos and probenazole on absorbent in air were ranged 80.9~121.1% in charcoal and 90.6~99.0% in XAD-4, respectively. Emission rate of in lysimeter was higher 3~5 times than that of pesticides from topsoil not added water at $35^{\circ}C$ plot after applying a mixture of granular formulation and soil. The ethoprophos concentration in air, 50 cm high from soil surface at greenhouse, was reached the highest 186.4 ${\mu}g/m^3$ within 13 hours and were ranged 17.8~186.4 ${\mu}g/m^3$ during 46 hours after applying granular formulation at dose rate 150 g a.i./245 $m^2$. The cadusafos concentration in air at greenhouse was reached the highest 37.3 ${\mu}g/m^3$ within 39 hours and were ranged 10.0~37.3 ${\mu}g/m^3$ during 46 hours after applying granular formulation at dose rate 180 g a.i./245 $m^2$. The probenazole concentration in air at greenhouse was reached the highest 1.45 ${\mu}g/m^3$ within 37 hours and were ranged 0.23~1.45 ${\mu}g/m^3$ during 46 hours after applying granular formulation at dose rate 144 g a.i./245 $m^2$. CONCLUSION(s): The result of the reentry interval study demonstrated that reentry intervals for ethoprophos and cadusafos are longer than 48 hours.

• Korean Journal of Soil Science and Fertilizer
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• v.29 no.4
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• pp.378-384
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• 1996

This study was conducted to investigate the influence of root zone temperature on the growth of shoot and root and the mineral contents in leaf of 'Fuji/M26' apple tree. Shoot growth and enlargement of trunk girth increased linearly with increasing root zone temperature. Fresh and dry weight of root reached maximum at $35^{\circ}C$. Water content of root increased with rising root zone temperature. The chlorophyll content of leaves showed insignificant difference with root zone temperature. Leaf water potential was high at $35^{\circ}C$ at 15 day after treatment but 60 day after treatment this was decreased. The nitrogen content of the leaves was not different by root zone temperature whereas the phosphorus content of the leaves was increased at $30^{\circ}C$ in 1993 and at $25^{\circ}C$ in 1994. The potassium content of the leaves reached a maximum at $30^{\circ}C$ in 1993 and $25^{\circ}C$ in 1994. In 1994 the calcium content of the leaves was increased with rising root zone temperature and with lengthening duration of treatment but no such differences were found in 1993. The magnesium content of the leaves was highest at $25^{\circ}C$ in 1993 and at $20^{\circ}C$ in 1994. The nitrogen and potassium content of the roots were increased linearly with root zone temperature in 1993 and 1994 and the magnesium and phosphorus content of the roots were high at $35^{\circ}C$ in 1994 but no such differences were found in the calcium content of the roots.

• Journal of Animal Environmental Science
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• v.1 no.2
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• pp.117-124
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• 1995

This study was carried out to investigate the effect of depth of sawdust bedding and ground material in dairy cattle barn. Treatment included the concrete floor with a 10cm or 30cm sawdust and the earth floor with a 30cm sawdust. Eighteen cows were assigned to 3 pens with 16.5㎥/head bedding area. The results obtained were as follows : 1. The temperature of sawdust bed was highest in the earth floor with 30cm sawdust, and the moisture content of sawdust bed was highest in the concrete floor with 10cm sawdust bed. 2. Cows defecate feces 9.2, 8.7 and 9.3 times a day in 10cm sawdust on concrete floor(10S+C), 30cm sawdust on concrete floor(30S+C) and 30cm sawdust on non concrete floor(30S+ NC) respectively. In average, they excreta 9.1 times/day(85.8%) in the sawdust beds and 1.5 times/day(14.2%) in the feeding alley. 3. The ratio of daily water amount deposited vapor to total water amount deposited in sawdust beds was 74.0%, 61.5% and 47.1% in 10S+C, 30S+C and 30S+NC respectively. 4. N.P.K contents in the sawdust beds were higher for 10S+C compared with other treatments. 5. When 30cm of sawdust was applied on the earth ground NO$_3$-N contents in the sawdust bed was 37.7, 14.1 and 15.0ppm in depth of 30, 60 and 90cm under the ground, respectively, indicating some possibility of water pollution.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.24 no.6
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• pp.644-653
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• 2013

In this paper, a formulation for obliquely incident electromagnetic wave has been presented for an analysis of highpower electromagnetic pulse penetration into multilayered dispersive media. Based on generalized models of measured dielectric constants and propagation channels reflecting the Earth's general features, the propagation phenomenon of the obliquely incident early-time(E1) high altitude electromagnetic pulse(HEMP) is analyzed. In addition, the polarization and critical angle are also considered. It is found that the total reflection occurs at an incident angle of about 38 degrees at the soil-rock interface, and that the parallel-polarized E1 HEMP penetrates better than the perpendicular-polarized one. The peak level of the penetrating electric field is found to be 5.6 kV/m at normal incidence, regardless of the type of polarization, and E1 HEMP is greatly reduced near the critical angle. Moreover, the penetrating E1 HEMP is analyzed as a variation of moisture content and depth of materials, resulting E1 HEMP could be useful in determining the levels of shielding required for buried facilities.

• Journal of Korea Water Resources Association
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• v.48 no.10
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• pp.831-843
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• 2015

This study estimates MODIS-derived evapotranspiration data quality by revised RS-PM algorithm in Seolmacheon test basin. We used latent flux with eddy covariance method to evaluate MODIS-derived spatial evapotranspiration and gap-filled these data by three methods (FAO-PM, MDV and Kalman Filter) and to quantify daily evapotranspiration. Gap-filled daily evapotranspiration data was used to evaluate evapotranspiration computed by revised RS-PM algorithm derived MODIS satellite images. For the water budget analysis, we used soil moisture content that is quantified to average individual soil moisture rate observed by TDR (Time Domain Reflectometry) sensor at soil depth. The soil moisture variation is calculated in consideration from initial to final soil moisture content. According to the result of this study, evapotranspiration computed by revised RS-PM algorithm is very larger than eddy covariance data gap-filled by three methods. Also, water budget characteristics is not closed. We could analysis that MODIS-derived spatial evapotranspiration does not represent actual evapotranspiration in Seolmacheon.