• 대한토목학회논문집
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• 제39권6호
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• pp.713-723
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• 2019

기후변화와 다양한 강우 패턴에 의하여 도시 유역 별 침수발생 기준을 산정하기에 어려움이 있다. 이에 도시 유역의 상세 지형, 배수체계 그리고 다양한 강우 시나리오를 고려하여 침수해석을 실시 및 결과를 검토할 필요가 있으며, 동일 지역에 대한 실측 강우에 따른 침수 사상을 조사할 필요가 있다. 본 연구에서는 서울시 효자 배수분구의 침수 발생에 영향을 미치는 강우 특성을 파악하기 위해 확률론적 빈도 분석과 Huff 분포를 고려한 다양한 강우 시나리오를 생성하였으며, 1차원 도시유출해석을 위한 SWMM (Storm Water Management Model)과 2차원 침수해석 모형을 이용하였다. 본 연구에서 사용된 SWMM 모형은 침수흔적도와 유전자 알고리즘을 통해 최적화 되었다. 최적화 된 1차원 모형을 2차원 침수해석과 연계하여 기존의 침수흔적도와 73.6 %의 적합도를 나타낼 수 있었다. 각 강우량에 따른 침수 발생 유무를 파악하였으며, 로지스틱 회귀 곡선을 통하여 침수발생 한계강우량을 산정할 수 있었다. 1-2차원 침수해석 결과와 2010~2018년 AWS (Automated Weather System)자료와 ASOS (Automated Synoptic Observing System)를 반영한 결과, 지속시간 1시간의 경우 침수발생 한계강우량은 72.04 mm, 2시간의 경우 146.83 mm, 3시간의 경우 203.06 mm으로 산정되었다. 산정된 한계강우량은 지속적으로 관측되는 강우 자료의 입력을 통하여 갱신될 수 있을 것으로 보인다. 본 연구에서 제시되는 방법론을 통해 도시 배수분구별 정량적 한계강우량을 제시할 수 있을 것으로 보이며, 이는 도시 유역에서 홍수 예·경보 발령을 위한 기초자료를 제공할 수 있을 것으로 판단된다.

• 한국수자원학회논문집
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• 제51권1호
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• pp.81-88
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• 2018

도시지역의 모든 하수관망을 사용하여 구축된 강우-유출모형은 그 규모가 방대하고 복잡하여 실시간 도시홍수예보에 적합하지 않다. 따라서 본 연구에서는 상대적으로 도시화가 많이 진행된 서울시의 상습침수지역인 도림천 대림배수분구의 하수관망도를 이용하여 강우-유출모형을 구축하고 이를 단순화하였다. 하수관망 단순화는 노드의 누가유역면적을 단순화의 범위 산정을 위한 기준으로 설정하고 총 5단계의 과정으로 나누었으며 단순화 과정에서 SWMM의 모든 매개변수들을 면적가중치를 적용하여 계산하였다. 또한 하수관망의 적정 단순화 범위를 산정하기 위하여 유출모형에 5가지 단순화 범위를 설정하고 유출분석과 침수분석을 실시하였다. 그 결과, 유출모형의 노드와 관망의 개수 그리고 모의시간 모두 단순화 범위에 따라 50~90%까지 일정하게 감소하였으며 단순화 이전과 동일한 유출량 결과를 나타내었다. 2차원 침수분석의 경우, 누가유역면적별로 단순화의 범위가 커질수록 월류지점의 개수가 크게 감소하고 위치가 바뀌었으나 비슷한 침수양상을 나타내었다. 다만 누가유역면적을 기준으로 6 ha 이상에서는 상류부터 삭제되는 노드에 의해 나타내지 못하는 침수지역이 발생하였다. 2차원 침수면적, 주요침수구간, 침수심 등을 비교 분석한 결과, 누가유역면적을 기준으로 1 ha의 단순화 범위가 단순화 이전의 분석결과와 가장 유사함을 나타내었다. 본 연구는 SWMM 매개변수를 모두 고려한 하수관망 단순화를 실시함으로써 실시간 도시홍수예보를 위한 신속하고 정확한 유출자료 생성에 활용될 수 있을 것으로 기대한다.

• Environmental Engineering Research
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• 제23권1호
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• pp.84-91
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• 2018

The present study deals with the management of groundwater resources of an important agriculture track of north-western part of Saudi Arabia. Due to strategic importance of the area efforts have been made to estimate aquifer proneness to attenuate contamination. This includes determining hydrodynamic behavior of the groundwater system. The important parameters of any vulnerability model are geological formations in the region, depth to water levels, soil, rainfall, topography, vadose zone, the drainage network and hydraulic conductivity, land use, hydrochemical data, water discharge, etc. All these parameters have greater control and helps determining response of groundwater system to a possible contaminant threat. A widely used DRASTIC model helps integrate these data layers to estimate vulnerability indices using GIS environment. DRASTIC parameters were assigned appropriate ratings depending upon existing data range and a constant weight factor. Further, land-use pattern map of study area was integrated with vulnerability map to produce pollution risk map. A comparison of DRASTIC model was done with GOD and AVI vulnerability models. Model validation was done with $NO_3$, $SO_4$ and Cl concentrations. These maps help to assess the zones of potential risk of contamination to the groundwater resources.

• Korean Journal of Hydrosciences
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• 제5권
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• pp.33-43
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• 1994

This study is to determine the critical duration of design rainfall and to utilize it for the design of detention pond with pump station. To examine the effect of the duration and temporal distribytion of the design rainfall, Huff's quartile method is used for the 9 cases of durations (ranges from 20 to 240 minutes) with ten years return period, and the ILLUDAS model is used for runoff analysis. The storage ratio, which is the ratio of maximum storage amounts to total runoff volume, is introduced to determine the criticalduration of design rainfall. The duration which maximizes the storage ratio is adopted as the critical duration. This study is applied to 18 urban drainage watercheds with pump station in Seoul, of which the range of watershed area is 0.24~12.70$km^2$. The result of simulation shows that the duration which maximizes storage ratio is 30 and 60 minutes on the whole. It is also shown that the storage ratios of 2nd - and 3rd-quartile pattern are larger than those of 1st- and 4th-quartile pattern of temporal distribution. A simplified empirical formula for Seoul area is suggested by the regression analysis between the maximum storage ratio and the peak ratio. This formula can be utilized for the preliminary design and planning of detention pond with pump station.

• 생물환경조절학회지
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• 제31권4호
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• pp.476-484
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• 2022

본 연구에서는 파프리카(Capsicum annuum L.) 'Scirocco' 품종 수경재배 시 배액 재사용 여부에 따른 순환식 재배와 비순환식 재배 및 배지 종류가 배액의 양분 이온 변화 양상과 생육에 미치는 영향을 조사하였다. 파프리카의 파종은 2021년 8월 19일에, 정식은 2021년 9월 16일, 순환식 및 비순환식의 재배 방식 적용은 2021년 10월 21일에 시행하였다. 배액 내 양분 분석 결과, Na⁺와 Cl^-은 작물이 제대로 흡수하지 않는 대표적은 이온으로써 생육이 진전될수록 순환식 재배방식에서 집적되었다. 또한 배액 내 NH₄-N의 함량이 NO₃-N의 함량에 비해 현저히 낮으므로 파프리카의 이온 선택성으로 인해 NO₃-N보다 NH₄-N이 우선 흡수되는 것으로 생각된다. 파프리카의 생육 및 과실 특성은 배액 재사용 여부와 배지의 종류에 따른 처리 간의 차이가 크지 않았다. 결론적으로 순환식과 비순환식의 수경재배 방식, 코이어와 암면의 배지 종류에 따른 파프리카 수경 재배 시 중기 이후의 세력약화로 인한 착과 불량을 유의하여 관리한다면 처리 간의 차이가 크지 않으므로 농가의 실정에 맞는 재배 방식과 배지를 선택하여 파프리카를 생산할 수 있을 것으로 생각된다. 다만 최근 환경오염에 대한 관심이 높아진 만큼 배액 재사용에 따른 병원균 감염 등을 잘 관리한다는 가정 하에서 순환식 재배 방식을 채택해도 수량 감소나 품질 저하 등은 우려하지 않아도 될 것이라 판단되며, 폐기 문제가 발생하는 암면 대신 코이어 배지를 선택한다면 더욱 환경오염 감소에 기여할 수 있으리라 기대된다.

• 한국지진공학회:학술대회논문집
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• 한국지진공학회 2002년도 추계 학술발표회 논문집
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• pp.11-18
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• 2002

The Ulsan fault with NNW-SSE strike is a very wide and long lineament about 50km along Gyeungju-Ulsan line in the southeastern part of Korea. According to previous studies the Ulsan fault was not considered as a fault but only long lineament since no displacement was found along the lineament. Recently several Quaternary faults were reported in the northeastern part of lineament, which implies the neotectonic movement in this area. We analysed drainage pattern and stream gradient using the DEM (Digital Elevation Model) data for both side of Ulsan fault line to check the recent topographic changes which indicate neotectonic movement. The result shows that stream index in the eastern part of Ulsan fault is higher than the one in the western part. This means that recent tectonic movement is more active in the eastern part of Ulsan fault.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2002년도 봄 학술발표회 논문집
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• pp.165-172
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• 2002

We presents an hazard zonation mapping technique in karst terrain and its assessment. From the detailed engineering geological mapping. Controlling factors of sink hole and limestone cave formation were discussed and 4 main hazard factors affecting hazard potential are identified as follows: prerequisite hazard factor(distributions of pre-existing sink holes and cavities), geomorphological hazard factors(slope gradient, vegetation, and drainage pattern etc.) geological hazard factors(lithology, fracture patterns and geological structures etc.) and hydraulic conditions(hydraulic head, annual fluctuation of ground water table and composition of g/w water). From the construction of hazard zonation map along the Jecheon-Maepo area, and vertical cross-sectional hazard zonations specific tunnel site we suggest hazard zonation rating systems.

• 한국농촌건축학회논문집
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• 제1권1호
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• pp.129-138
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• 1999

The aim of this study is to obtain new design factors which can be applied to the constructing design of bathrooms. This study was especially focused on the using patterns of the bathrooms of the rural apartment houses in Chungbuk Province which have been constructed by the public program to improve old farm houses. To carry out this study, field study, questionnaire survey and personal interview have been made. The results are as follows. 1) It is essential to lay out a bathtub, because farmers need to relieve their fatigue caused by manual labor, and mostly they don't find a bathhouse in the neighborhood. 2) With the drainage way, it is necessary to equip an apparatus to collect and remove the fallen hair and garbage which usually stop up the beak. 3) Considering the using patterns of the bathrooms as the place of washing one's face, foot, hair and clothes, one more hydrant is needed in the bathroom besides the two hydrants in the washstand and bathtub.

• Journal of Korean Neurosurgical Society
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• 제46권2호
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• pp.136-143
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• 2009

Objective: Remote cerebellar hemorrhage (RCH) is one of the rare complications occurring after supratentorial surgery, and its pathomechanism is poorly understood. We report 10 cases of RCH from our institution and review 154 cases from a database in order to delineate incidence, common presentation, risk factors, and outcomes of this complication. In addition, the means of prevention are discussed. Methods: We reviewed the medical records of 10 patients who experienced RCH after undergoing supratentorial surgery at our institution between 2001 and 2008. A database search in Medline revealed 154 cases of RCH in the English literature. Characteristic features were analyzed and compared. Results: There were 10 cases of RCH among 3307 supratentorial surgery cases, indicating a 0.3% incidence. All patients had characteristic imaging features of RCH, namely a streaky bleeding pattern in the superior folia of the cerebellum. Seven patients had a history of preoperative hypertension. Four cases were related to cerebral aneurysms, and other four developed after the removal of brain tumors. Cerebrospinal fluid (CSF) drainage apparatuses were installed postoperatively in all cases. Outcomes according to modified Rankin scale (mRS) were good in 7 patients, with 1 fatal case. Conclusion: RCH is a rare complication after supratentorial surgery, and the exact etiology still remains uncertain. Hypertension and perioperative loss of CSF seem positively correlated with RCH, but no single risk factor is totally responsible. Patients with RCH should be closely observed to improve their prognosis.

• 한국작물학회지
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• 제44권1호
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• pp.32-37
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• 1999

The experiment was conducted to investigate emergence response of lowland weeds at different soil moisture contents, burying depths and upon changes in soil moisture. Rice germination was over 50% at all burying depths under aerobic condition, but the emergence rate of the soil surface placed seeds in saturated and flooded conditions decreased by 19% and 29%, respectively, as compared with that of aerobic condition. Rice seeds at burying depth of over 3 cm did not emerge at all. The emergence rate of Echinochloa crus­galli (L.) Beauv. in aerobic condition was lower than 30%, but the emergence pattern of E. crus galli (L.) Beauv. at different soil moisture contents and seeding depths was similar to that of rice. Emergence behavior of lschaemum rugosum Salisb., Ludwigia octovalvis (Jacq.) Raven and Sphenoclea zeylanica Gaertn. which are dominant lowland weed species in the Philippines also differed depending on soil moisture conditions and burying depths. lschaemum rugosum Salisb. emerged at all burying depths under aerobic condition, whereasLudwigia octovalvis (Jacq.) Raven emerged only at 0 cm deep under saturated and aerobic condition and Sphenoclea zeylanica Gaertn. at 0 cm deep under flooding condition. Weed seeds planted at 1, 3, and 5 cm deep in continuous flooded and saturated condition did not emerge at all, but upon a change of soil moisture condition from saturated to drainage (S$\rightarrow$D) and flooded to drainage (F$\rightarrow$D), grass weeds began to germinate again and the average emergence rate in S$\rightarrow$D and F$\rightarrow$D were 26% and 5% forE. crus­galIi (L.) Beauv., 9% and 8% forI. rugosum SaIisb., respectively. Weed seeds buried in soil in the pot showed great emergence at S$\rightarrow$D but did not emerge under continuous flooded condition. The diversity index accounting for dominance degree and occurrence aspect of weed, was the lowest at F$\rightarrow$D.