• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 1998.05a
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• pp.153-157
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• 1998

무등산 수박의 유묘 생산에 있어 적정 배양액 농도를 구명하기 위하여 일본원시균형배양액을 기준으로 하여 NO$_3$-N, K 및 Ca의 농도별 첨가량에 따른 유묘생장반응을 조사하였다. 1. 배양액내 질소농도을 증가시킬수록 초장, 엽면적, 엽수, 엽장, 엽폭이 증가하였으며 생체중과 건물중도 증가하였다. 2. 배양액내 칼륨의 농도를 증가시켰을 경우 수박 유묘의 초장은 200ppm까지는 약간 증가하지만 엽면적, 엽수, 엽장, 생체중 및 건물중은 200ppm이상으로 증가시키면 감소하는 경향이었다. 3. 칼슘처리의 경우 농도의 증가가 생장의 증가를 나타내지는 않았으며 원시균형 배양액의 표준이라 할 수 있는 80ppm처리구의 생장이 양호한 것으로 나타났다. 4. 배양액(일본원시균형배양액 1/2농도)에 N의 농도를 200ppm으로 증가시킬 경우 수박유묘의 엽병내 N, K 및 Mg의 함량이 증가하였지만 P 및 Ca의 증가나 감소의 경향은 보이지 않았다. 5. K의 농도를 100ppm으로 증가시킬 경우 수박유묘의 엽병내 N, K 및 Mg의 함량이 증가하였지만 P 및 Ca의 증가나 감소의 경향은 보이지 않았다. 5. K의 농도를 150ppm으로 증가시킬 경우 수박유묘의 엽병내 N, K 및 Mg의 함량이 증가하였지만 P 및 Ca의 증가나 감소의 경향은 보이지 않았다. 그러나 200ppm이상으로 증가시킬 경우 N과 Mg의 감소가 나타났다. 6. 양액내 Ca의 농도를 증가시킬수록 엽병내 N, K Ca 및 Mg의 농도가 증가하는 반면 P의 경우 거의 변화가 없었으며,N의 경우는 200ppm 이상의 농도에서 감소하는 경향을 나타내었다. Mg의 경우는 150ppm까지는 함량의 변화가 없었지만 200ppm 이상의 처리구에서 급격한 함량증가를 나타내었다.~21.2ml가 흘러나와 배지의 공극이 일정하지 않아 시간당 통과하는 양이 일정하지 않았다고 생각되었다. $\bigcirc$ 펄라이트 : 합섬A(비스코스+레이온)급액천의 유입은 소(1$\times$60cm)에서 21.8ml, 중(2$\times$60cm) 33.5ml, 대(3$\times$60cm) 43.4ml가 통과되었고 합섬(폴리에스텔)에서는 19.0~30.7ml로서 급액천의 규격에 따라 통과되는 차이가 있었다. 배지가 규격화되어 있어 급액천의 규격별로 일정하게 유입되었으며 급액천의 재질이 유입에 영향을 미친 것으로 사료되었다. (2) 급액관과 베드상과의 높이에 따른 유출양 : 급액과 베드상과의 낙차가 클수록 유출이 증가함을 알수 있었으나 합섬C(인견)실험구에서는 낙차가 유출에 영향을 미치지 않았다. (4) 급액된 양액의 EC 및 pH조사 : 급액된 양액의 EC 및 pH에 전혀 변화가 없어 재배 적응에 문제가 없을것으로 사료되었다.이가 가장 이상적인 것으로 생각된다.세포수에 대한 내부세포괴세포(ICM/total cells)가 20~40% 범주에 드는 비율은 처리구가 대조구보다 낮은 결과를 나타냈다. 결론적으로 돼지난포란을 이용하여 체외성숙을 유기할 때 효과적인 cysteamine의 농도는 50$\mu$M이 적당하며, 초기배발달을 유기할 때의 효과적인 cysteamine의 농도는 25~50$\mu$M인 것으로 판단된다.N)A(N)/N을 제시하였다(A(N)=N에 대한 A값). 위의 실험식을 사용하여 헝가리산 Zempleni 시료(15%$S_{XRD}$)의 기본입자분포로부터 %$S_{XRD}$를 계산한

• Journal of Wetlands Research
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• v.22 no.3
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• pp.171-177
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• 2020

To improve the nitrogen reduction capability of stormwater treatment systems subjected to intermittent saturation, organic materials are often added as filter media. However, these materials can be an additional source of organic carbon and increase the chemical oxygen demand (COD) in the outflow. In this study, different types of organic filter media were subjected to a batch leaching test to observe and quantify the release of COD. Results reveal that the initial pH of the tap water used for soaking which is 7.5-7.7 is conducive to the release of organics from the media to the leachate. The highest amount of COD released was observed in yard clippings and woodchip followed by compost and bark mulch. The leaching of organics also increased as the size of the media decreases due to higher surface area per volume. In addition, empirical regression analysis predicted that COD from these organic media will be exhausted from the material in 3-5 months to up to 26 months depending on the type of media. The results of this study can serve as a guide in estimating the potential release of COD in organic media in order to ensure their safe application in stormwater treatment facilities.

• Proceedings of the Korea Water Resources Association Conference
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• 2004.05b
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• pp.753-758
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• 2004

건천화란 하천이 건천이 되어가는 과정이라고 할 수 있다. 그러나 이의 정량적 접근이 어려운 이유는 건천이 되어가는 과정에 대한 현상을 지속적으로 관찰하기 어렵고, 순수한 자연현상이라기보다 인위적 요소가 간섭한 결과이기 때문이다. 본 연구는 건천이 되어가는 하천 중에서도 도시화에 의한 건천화의 영향이 큰 것으로 보이는 우이천 유역에 대해 건천화의 원인을 분석하여 몇 가지 결론과 대책을 제시하였다. 우이천은 유역면적 $27.67km^2$, 유로연장 11.75km의 비교적 좁은 면적 내에 인구 461,351명이 거주하고 주변 행정구역 총 인구가 604,282명인 지방2급하천이다. 유역 내 북부와 북서부의 산악지역을 통과하는 상류는 대부분 계류(溪流)로서 자연상태를 유지하고 있으나, 중${\cdot}$하류는 양안의 셋방, 복개, 직강화, 보 및 낙차공 등 인공구조물로 인해 하천형상이 크게 왜곡되어 있는 전형적인 도시하천유역이다. 본 연구는 우이천에 대한 건천화 원인분석을 위해 크게 4가지 방봅으로 접근하였는데 반분포형 유출모형인 TOPMODEL에 의한 장기유출분석, 수문${\cdot}$기상자료에 의한 분석, 인문${\cdot}$사회자료의 분석, 지하수위 분석 등이었다. 분석결과 우이천 유역과 같이 장기간에 걸쳐 도시화가 진행된 유역은 수문순환계의 왜곡이 돌이킬 수 없는 수준이므로, 적절한 건천화 방지대책의 방향은 건천화의 원인이 되는 인자를 제거함으로써 줄어든 유량을 회복하는 방안보다는 인위적이고 강제적인 방식으로 추가적인 하천수량을 확보하는 것이 타당하다 사료된다. 하천의 건천화는 하나의 주된 원인이 지배적일 수도 있지만 간접적인 영향이 많고, 하나의 원인이 다른 인자에 영향을 주어 연쇄적인 영향을 미칠 수도 있는 복잡한 현상이다. 따라서 다양한 각도에서 다양할 접근방식으로 방지대책을 수립하여야 할 것이다.적에 따른 임계지속기간과 유출량의 변화를 검토해 보았다.이를 각각의 경우의 해석해 결과와 비교${\cdot}$분석하였다. 후방추적 퍼프모형은 전방추적 퍼프모형에 비하여 사용된 퍼프수와 관계없이 작은 오차를 발생하였으며, 전체적으로 퍼프 모형이 입자모형보다는 훨씬 적은 수의 계산을 통해서도 작은 오차를 나타낼 수 있다는 것을 알 수 있었다. 그러나 Gaussian 분포를 갖는 퍼프모형은 전단흐름에서의 긴 유선형 농도분포를 모의할 수 없었고, 이에 관한 오차는 전단계수가 증가함에 따라 비선형적으로 증가하였다. 향후, 보다 다양한 흐름영역에서 장${\cdot}$단점 분석 및 오차해석을 수행한 후에 각각의 Lagrangian 모형의 장점만을 갖는 모형결합 방법을 제시할 수 있을 것으로 판단된다.mm/$m^{2}$로 감소한 소견을 보였다. 승모판 성형술은 전 승모판엽 탈출증이 있는 두 환아에서 동시에 시행하였다. 수술 후 1년 내 시행한 심초음파에서 모든 환아에서 단지 경등도 이하의 승모판 폐쇄 부전 소견을 보였다. 수술 후 조기 사망은 없었으며, 합병증으로는 유미흉이 한 명에서 있었다. 술 후 10개월째 허혈성 확장성 심근증이 호전되지 않아 Dor 술식을 시행한 후 사망한 예를 제외한 나머지 6명은 특이 증상 없이 정상 생활 중이다 결론: 좌관상동맥 페동맥이상 기시증은 드물기는 하나, 영유아기에 심근경색 및 허혈성 심근증 또는 선천성 승모판 폐쇄 부전등을 초래하는 심각한 선천성 심질환이다. 그러나 진단 즉시 직접 좌관상동맥-대동맥 이식술로 수술적 교정을 해줌으로써 좋은 성적을 기대할 수 있음을 보여주었다.특히 교사들이 중요하게 인식하는 해방적 행동에 대한 목표를 강조하여 적용할 필요가 있음을 시사하고 있다.교하여 유의한 차이가 관찰되지 않았다. 또한 HSP 환자군에서도 $IL1RN^{*}2$ allele 빈도와 carria

• Journal of Korea Water Resources Association
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• v.41 no.2
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• pp.229-239
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• 2008

This study is to derive the fourth-order Geomorphologic Instantaneous Unit Hydrograph (GIUH), driven for only third-order basin, for the application of GIUH to various types of basin. The second, third, and fourth order GIUHs were compared for various topographical conditions. The results showed lower peak runoff and later peak time in GIUH with higher stream order. Initial state probability was estimated from a function of geomorphologic parameters such as area ratio and bifurcation ratio for the application of GIUH. However, initial state probabilities and early parts of the GIUHs have negative values for many basins due to the inherent errors in the parameters. Initial state probability was calculated by area ratio of direct drainage using ArcView GIS 3.2 model to solve the problem. GIUHs were estimated for three basins, Sanganmi, Byeongcheon, and Sangye, using the above suggested method, and the results showed that the method is free of the problem.

• Fire Science and Engineering
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• v.33 no.5
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• pp.37-47
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• 2019

In the present study, the influences of the fire curtain and natural vent in a theater fire were investigated through the numerical simulation of a reduced-scale model of a theater fire using the Fire Dynamics Simulator (FDS). Based on a previous experimental study using the reduced-scale model, the 1/14 reduced-scale model and its conditions were constructed according to the law of similarity with a real-scale theater. Through a series of numerical simulations, the smoke movements were visualized, and the temperatures in the stage and auditorium, mass flow rate of the outflow through natural vent, and time at which smoke started moving toward the auditorium were measured and analyzed. The general trends on the effects of the fire curtain and natural vent during the theater fire predicted by the present numerical simulation were similar to the previous experimental results. For quantitative comparison of the present numerical simulation and previous experimental results, the mean percentage errors of temperatures in the stage and auditorium, and the mass flow rate of outflow through the natural vent were calculated. The present numerical simulation results showed good agreement with previous experimental results with reasonable accuracy.

• Journal of Korea Water Resources Association
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• v.47 no.5
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• pp.435-446
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• 2014

Various drought indices developed from previous studies can not consider the inherent uncertainty of drought because they assess droughts using a pre-defined threshold. In this study, to consider inherent uncertainty embedded in monthly streamflow data, Hidden Markov Model (HMM) based drought index (HMDI) was proposed and then probabilistic assessment of hydrologic drought was performed using HMDI instead of using pre-defined threshold. Using monthly streamflow data (1966~2009) of Pyeongchang river and Upper Namhan river provided by Water Management Information System (WAMIS), applying the HMM after moving-averaging the data with 3, 6, 12 month windows, this study calculated the posterior probability of hidden state that becomes the HMDI. For verifying the method, this study compared the HMDI and Standardized Streamflow Index (SSI) which is one of drought indices using a pre-defined threshold. When using the SSI, only one value can be used as a criterion to determine the drought severity. However, the HMDI can classify the drought condition considering inherent uncertainty in observations and show the probability of each drought condition at a particular point in time. In addition, the comparison results based on actual drought events occurred near the basin indicated that the HMDI outperformed the SSI to represent the drought events.

• Journal of Soil and Groundwater Environment
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• v.11 no.5
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• pp.9-19
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• 2006

The accurate estimation of groundwater recharge is important for the proper management of groundwater systems. The widely used techniques of groundwater recharge estimation include water table fluctuation method, baseflow separation method, and annual water balance method. However, these methods can not represent the temporal-spatial variability of recharge resulting from climatic condition, land use, soil storage and hydrogeological heterogeneity because the methods are all based on the lumped concept and local scale problems. Therefore, the objective of this paper is to present an effective method for estimating groundwater recharge with spatial-temporal variability using the SWAT model which can represent the heterogeneity of the watershed. The SWAT model can simulate daily surface runoff, evapotranspiration, soil storage, recharge, and groundwater flow within the watershed. The model was applied to the Musimcheon watershed located in the upstream of Mihocheon watershed. Hydrological components were determined during the period from 2001 to 2004, and the validity of the results was tested by comparing the estimated runoff with the observed runoff at the outlet of the catchment. The results of temporal and spatial variations of groundwater recharge were presented here. This study suggests that variations in recharge can be significantly affected by subbasin slope as well as land use.

• Journal of Korea Water Resources Association
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• v.35 no.3
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• pp.321-330
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• 2002

This study aims at the analysis of the geomorphological instantaneous unit hydrograph model (GIS-GIUH) with geographic information system for the rainfall-runoff analysis of watershed which is ungaged or doesn't have sufficient hydrologic data. The rainfall-runoff analysis was performed in Wi stream(Dongkok, Koro, Miseung, Byeungchun, Hyoreung, Museung) which is a representative experimental river basin of IHP. In the process of analysis of the GIUH model, developed GIS-GIUH model and Rosso-GIUH model were applied the study basin and computed hydrographs by these models were compared with observed hydrograph. The GiS-GIUH model shows more closely to the observed hydrograph than Rosso-GIUH model in the peak discharge of the hydrograph. For the development of the GIS-GIUH model, Gamma function factor N was given by N=3.25( $R_{B}$/ $R_{A}$)$^{0.126}$ $R_{L}$$^{-0.055}$, which is the relation of the watershed geomorphological factor, K was also obtained as K=1.50( $R_{A}$/( $R_{B}$. $R_{L}$))/$^{0.10}$.(( $L_{{\Omega}}$+ $L_{{\Omega}-1}$)/V)$^{0.37}$. As the results of analysis, it was found that GIS-GIUH model can be applied to an ungaged watersheds.eds.

• Journal of Wetlands Research
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• v.20 no.3
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• pp.235-242
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• 2018

The function of vertical subsurface flow wetlands can potentially be reduced with time due to clogging and are often assumed to be occurring when ponding and overflow is observed during rainfall. To investigate their clogging potential, three pilot-scale vertical subsurface flow (VSF) wetland systems were constructed employing woodchip, pumice, and volcanic gravel as main media. The systems received stormwater runoff from a highway bridge for seven months, after which the media were taken out and divided into layers to determine the amount and characteristics of the accumulated clogging matters. Findings revealed that the main clogging mechanism was the deposition of suspended solids. This is followed by the growth of biofilm in the media which is more evident in the wetland employing woodchip. Up to more than 30% of the clogging matter were found in the upper 20 cm of the media suggesting that this layer will need replacement once clogging occurs. Moreover, no signs of clogging were observed in all the wetlands during the operation period even though an estimation of at least 2 months without clogging was calculated. This was attributed to the intermittent loading mode of operation that gave way for the decomposition of organic matters during the resting period and potentially restored the pore volume.

• Journal of the Korean Association of Geographic Information Studies
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• v.12 no.3
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• pp.164-178
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• 2009

This study was aimed to make GIS oiling thematic maps and analyze temporal oiling variation patterns for two months after 'Hebei Spirit' oil spill accident in December 7, 2007 using GIS and oiling status surveyed data. As a basic work for making of oiling thematic maps, geometric corrections were performed with IKONOS images using ground control points data. These corrected images were used to make detailed coastline from digital charts, and then spatial unit of coastline were defined using classified coastline types. And to know the representative parameters which reflect oiling situation, relationship between oiling status parameters extracted from four times oiling assessment reports and total petroleum hydrocarbons (TPHs) data (December 2007 and January 2008) monitored by Korea Ocean Research and Development Institute (KORDI). Using these representative oiling status parameters pollution value were calculated, and they were keyed into spatial unit of coastline as attributive value. GIS oiling status thematic maps made with coastline containing pollution value showed the initial two month's situations somewhat well. Also, to analyze temporal variation pattern of coastline types, about 13.4km length coastline around Malripo beach was defined as detailed study area where is the common spatial zone surveyed oiling status by each organizations. Based on this study results, it could be possible to provide oiling status maps quickly and to support decision making for oiling control action and scientific pollution monitoring.