• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.6
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• pp.2255-2265
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• 2013

This study presents the width function-based Clark model. To this end, rescaled width function with distinction between hillslope and channel velocity is used as time-area curve and then it is routed through linear storage within the framework of not finite difference scheme used in original Clark model but analytical expression of linear storage routing. There are three parameters focused in this study: storage coefficient, hillslope velocity and channel velocity. SCE-UA, one of the popular global optimization methods, is applied to estimate them. The shapes of resulting IUHs from this study are evaluated in terms of the three statistical moments of hydrologic response functions: mean, variance and the third moment about the center of IUH. The correlation coefficients to the three statistical moments simulated in this study against these of observed hydrographs were estimated at 0.995 for the mean, 0.993 for the variance and 0.983 for the third moment about the center of IUH. The shape of resulting IUHs from this study give rise to satisfactory simulation results in terms of the mean and variance. But the third moment about the center of IUH tend to be overestimated. Clark model proposed in this study is superior to the one only taking into account mean and variance of IUH with respect to skewness, peak discharge and peak time of runoff hydrograph. From this result it is confirmed that the method suggested in this study is useful tool to reflect the heterogeneity of drainage path and hydrodynamic parameters. The variation of statistical moments of IUH are mainly influenced by storage coefficient and in turn the effect of channel velocity is greater than the one of hillslope velocity. Therefore storage coefficient and channel velocity are the crucial factors in shaping the form of IUH and should be considered carefully to apply Clark model proposed in this study.

• Journal of Korea Water Resources Association
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• v.40 no.9
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• pp.697-707
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• 2007

In this study, we estimated the PMP(Probable Maximum Precipitation) and its transition in case of the typhoon Rusa which happened the biggest damage of all typhoons in the Korea. Specially, we analysed the moisture maximizing rate under the consideration of meteorological condition based on the orographic property when it hits in Gangneung region. The PMP is calculated by the rate of the maximum persisting 12 hours 1000 hPa dew points and representative persisting 12 hours 1000 hPa dew point. The former is influenced by the moisture inflow regions. These regions are determined by the surface wind direction, 850 hPa moisture flux and streamline, which are the critically different aspects compared to that of previous study. The latter is calculated using statistics program (FARD2002) provided by NIDP(National Institute for Disaster Prevention). In this program, the dew point is calculated by reappearance period 50-year frequency analysis from 5% of the level of significant when probability distribution type is applied extreme type I (Gumbel distribution) and parameter estimation method is used the Moment method. So this study indicated for small basin$(3.76km^2)$ the difference the PMP through new method and through existing result of established storm transposition and DAD(Depth-Area-Duration). Consequently, the moisture maximizing rate is calculated in the moisture inflow regions determined by meteorological fields is higher $0.20{\sim}0.40$ range than that of previous study. And the precipitation is increased $16{\sim}31%$ when this rate is applied for calculation.

• Journal of the Korean Institute of Landscape Architecture
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• v.39 no.4
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• pp.83-97
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• 2011

In this study, space allocation with an assessment system for improving the function of the ecological use and function of each space was undertaken to suggest appropriate goals and directions. Ogeum Park, used as the study site, is a stronghold green zone located in the fan-shaped area of the Songpa-gu green zone on a 22ha area site. The assessment system for this study consisted of a total of 3 steps: Step 1 includes the division of the spatial block, Step 2 assesses the proper functioning of each spatial block, while Step 3 includes space allocation and presents improvements for function by space. This study performed a basin analysis with the consideration that Ogeum Park is a forest area and divided the site into a total of 8 areas according to how the sections of land are used. The function of wildlife habitat included an analysis of plant ecology(vegetation type, vegetation layer, potential vegetation), animal ecology(wild birds), and waterways. The function of leisure and use included an analysis of gradients, noise, paths, status of use, and status of facilities. The evaluation of the function of habitat sorted items into native vegetation, vegetation diversification, vegetation potential, animal diversification and potential of animal habitats. The results of grading the evaluation scores by space in the function of habitat showed that the Areas IV and VII, which were 90% of the maximum point, were Grade A, Areas II and V were Grade B at 70% and Area I and VI were Grade C at 50%. Areas III and VIII, which were not found to be beyond the standard of 50%, were excluded. The evaluation of the functions of leisure and use classified items into use potential, use preference, use concentration, use diversification and use convenience. The results of the graded evaluation scores by space in use function, showed areas V and VI as Grade A, or 90% of the maximum score. Grade B, 70% of the maximum score, was given to Areas I and VII. Grade C, 50% of the maximum score, included Areas II, IV and VIII. Area III, graded lower the standard of 50%, was excluded. The study evaluated areas according to a common standard, classified spaces by proper functions into ecological spaces, environmentally-friendly use spaces and use spaces according to the standard of spatial distribution on the basis of the above results through a synthesis of grades of habitat function, leisure function and use. This offers ideas for the improvement of wildlife habitat and environment-friendly use functions by space.

• Korean Journal of Agricultural Science
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• v.19 no.2
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• pp.201-237
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• 1992

본(本) 연구(硏究)는 1992년(年) 2월(月)부터 동년(同年) 8월(月)까지 한국(韓國)의 농어촌진흥공사(農漁村振興公社)(RDC)와 말레시아의 KTA기술용역단간(技術用役團間)의 기술제휴하(技術提携下)에 아세아개발은행(亞細亞開發銀行)의 기술협력기금(技術協力基金)에 의(依)한 말레지아북부(北部) Terengganu 농촌개발제(農村開發第)2단계사업(段階事業)의 타당성조사연구(妥當性調査硏究) 결과(結果) 중 말레시아정부(政府)의 경제정책방향(經濟政策方向), 농업개발(農業開發) 및 사업(事業)의 경제적(經濟的) 재무적(財務的) 타당성(妥當性)만을 발췌(拔萃)하여 본(本) 논문(論文)에 수록(收錄)하였다. 본(本) 농촌개발사업지구(農村開發事業地區)는 말레시아의 북동(北東)쪽에 위치(位置)하고 있는 Terengganu State의 Setiu-Besut양(兩) Distict가 포함(包含)되는데 경제적(經濟的)으로 가장 낙후(落後)된 지역(地域)으로 매년(每年) 행사(行事)처럼 찾아오는 홍수(洪水)때문에 농경지(農耕地)를 집약적(集約的)으로 경작(耕作)하지 못함으로써 지역농민(地域農民)들은 빈곤(貧困)에서 벗어나지 못하고 있고 침수기간중(浸水期間中)에는 지역(地域)의 경제활동(經濟活動)은 물론(勿論) 교통(交通)마저 불통(不通)되고 농촌하부구조(農村下部構造)의 손실(損失)은 물론(勿論) 사회경제적(社會經濟的)인 손실(損失)이 크며 Setiu River의 하구(河口)가 침전(沈澱)되어 어선(漁船)의 출입(出入)이 점점(漸漸) 곤란(困難)해지므로써 어민(漁民)들의 생계(生計)에도 위협(威脅)을 주는 지역(地域)이다. 따라서 본(本) 타당성(妥當性) 조사연구(調査硏究)의 근본적(根本的)인 목적(目的)은 농촌(農村)의 빈곤(貧困)을 타파(打破)하기 위하여 (1) 홍수(洪水)를 방지(防止)하고, 배수(排水) 및 관개개선(灌漑改善)을 하며, 하구(河口)를 개발(開發)하여 어민(漁民)들의 생산활동(生産活動)을 돕고 지역주민(地域住民) 및 농민(農民)들의 경제활동(經濟活動) 및 농업생산성(農業生産性)을 제고(提高)시키며 (2) 환경보호(環境保護) 및 관리(管理)를 통(通)하여 지역주민(地域住民)에게 쾌적(快適)한 농촌생활환경(農村生活環境)을 제공(提供)하고 생태계(生態系)의 변화(變化)를 방지(防止)하며 (3) 다각적(多角的)인 영농활동(榮農活動)을 통(通)하여 지역농민(地域農民)의 소득(所得)을 극대화(極大化) 할 수 있는 개발(開發)의 기본구상(基本構想)과 이에 대한 기술적(技術的) 경제적(經濟的) 타당성(妥當性)을 구명(究明)하는 것이다. 본(本) 사업지역(事業地域)의 총면적(總面積)은 9,500ha이며 이는 4,680ha의 기설지구(旣設地區)의 개보수관개사업(改補修灌漑事業)과 500ha의 과수단지(果樹團地), 200ha의 채소단지(菜蔬團地), 500ha의 옥수수단지(團地), 250ha의 엽연초생산단지(葉煙草生産團地), 2,760ha의 오일팜 및 고무나무단지에 소, 염소 및 양(洋)을 사육(飼育)하는 종합적(綜合的)인 농촌개발(農村開發)로서 농가(農家)의 농업소득제고(農業所得提高)에 큰 기여(寄與)를 하게 되며 Setiu강(江)의 유역(流域) 4,090ha에 대한 홍수경감대책(洪水輕減對策)으로 지역주민(地域住民)의 생활안정(生活安定) 및 교통(交通), 관광(觀光), 사회경제적(社會經濟的) 생산활동(生産活動)을 촉진(促進)하는 사업(事業)을 하게된다. 본(本) 사업(事業)의 공사기간(工事期間)은 1993년(年)부터 5개년간(個年間)이며 총사업비(總事業費)는 외화(外貨) 2천만불(千萬弗)을 포함(包含)하여 5천(千) 5백만불(百萬弗)로 추정(推定)되었다. 년간사업수익(年間事業收益)은 사업(事業)의 완전운영기간(完全運營期間)인 2003년(年)을 기준(基準)으로 할 때 15,541백만불(百萬弗)로 추정(推定)되었으며 사업(事業)의 내구기간(耐久期間)은 30년(年)으로서 2023년(年)까지 생산(生産)이 계속(繼續)될 것이다. 본(本) 사업(事業)의 전체재무수익율(全體財務收益率)은 22.49%이며 경제적(經濟的) 수익률(收益率)은 19.30%로 경제적(經濟的)인 타당성(妥當性)이 매우 높음을 알 수 있다. 모든 사업(事業)이 계획(計劃)대로 성공적(成功的)으로 추진(推進)될 경우 사업지역내(事業地域)의 몽리농가(蒙利農家) 4,000호(戶)가 큰 혜택(惠澤)을 보게되고 농촌(農村)의 빈곤수준(貧困水準)(Poverty Line)은 현재(現在)의 36%에서 18%수준(水準)으로 경감(輕減)될 것이 기대(期待)되고 있다.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.1 no.1
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• pp.3-17
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• 1998

The purposes of this study is to investigate the possibility of planting trees at space land in the riverside. The space land is for the green space. Calculating the plantable space in the representation section and the flood flowing stability of the existing banks based on the hydrological and meteorological data of the Kap-Chon riverbasin located in Tae-jon, the following results are drawn. (1) The flood discharges in each flow section are $698.7m^3/s$ in section 1, $654.6m^3/s$ in section 2, and $1353.3m^3/s$ in section 3 during 100 years recurrence interval. Because the designed-flood discharges in those sections are $1719.9m^3/s$, $2119.7m^3/s$, and $1512.8m^3/s$ respectively, safety for flood flowing is sufficient in existing banks. (2) The possible clearance for planting trees is 1.80m in section 1, 3.90m in section 2, and 0.01m in section 3. Planting clearance is enough in section 1 and 2. However, planting should be planned after estimating a rise-height due to the bridge piers, because many piers under riverine-highway are now on the construction in section 2. The section 3 does not have sufficient clearance for planting trees, but the planting is possible after getting enough flow area with slope by cutting the terrace land on the river artificially heightened. (3) In case of planting a tree 70cm diameter in $1m^2$ in section 1, the water level increases by 0.60m. Planting a tree in a $48m^2$ area increases the water level by 0.90m. Considering that plantable clearance is 1.8m in section 1, it is sufficient to flow safely. But if the trees are planted so compactly from the upper stream, expected heavy resistance is expected due to caught materials on the trees. So, trees have to be planted widely in upper streams but compactedly in lower streams. (4) The river width without changing, Kap-Chon's flow channel can be snaked in accordance with the nature law the wide terrace land in the riverside. Decreased flow area due to planting trees will be compensated by the inclination of terrace land. And, it is theoretically proved that the flood discharge is safe even though the terrace land on the river is parked similar to the nature. Planting trees in the terrace land of the Kap-chon river to the extent that flood flowing is not adversely affected, we can get the enjoyable park to citizens not spending expensive cost. It also contributes to the recovery of ecosystem, which gives the natural beauty of river and shade to citizens and becomes good natural-educational places for children.

• Journal of Korea Water Resources Association
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• v.54 no.10
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• pp.819-833
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• 2021

This study is to evaluate applicability of linkage modeling using PHABSIM (Physical Habitat Simulation System) and SWAT (Soil and Water Assessment Tool) and to estimate ecological flow for target fishes of Andong downstream (4,565.7 km²). The SWAT was established considering 2 multi purpose dam (ADD, IHD) and 1 streamflow gauging station (GD). The SWAT was calibrated and validated with 9 years (2012 ~ 2020) data of 1 stream (GD) and 2 multi-purpose dam (ADD, IHD). For streamflow and dam inflows (GD, ADD and IHD), R², NSE and RMSE were 0.52 ~ 0.74, 0.48 ~ 0.71, and 0.92 ~ 2.51 mm/day respectively. As a result of flow duration analysis for 9 years (2012 ~ 2020) using calibrated streamflow, the average Q185 and Q275 were 36.5 m³/sec (-1.4%) and 23.8 m³/sec (0%) respectively compared with the observed flow duration and were applied to flow boundary condition of PHABSIM. The target stream was selected as the 410 m section where GD is located, and stream cross-section and hydraulic factors were constructed based on Nakdong River Basic Plan Report and HEC-RAS. The dominant species of the target stream was Zacco platypus and the sub-dominant species was Puntungia herzi Herzenstein, and the HSI (Habitat Suitability Index) of target species was collected through references research. As the result of PHABSIM water level and velocity simulation, error of Q185 and Q275 were analyzed -0.12 m, +0.00 m and +0.06 m/s, +0.09 m/s respectively. The average WUA (Weighted Usable Area) and ecological flow of Zacco platypus and Puntungia herzi Herzenstein were evaluated 76,817.0 m²/1000m, 20.0 m³/sec and 46,628.6 m²/1000m, 9.0 m³/sec. This results indicated Zacco platypus is more adaptable to target stream than Puntungia herzi Herzenstein.

• Ecology and Resilient Infrastructure
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• v.9 no.3
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• pp.163-173
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• 2022

Climate change is a key factor that greatly influences changes in the biological seasons and geographical distribution of species. In the ecological field, the BioClimatic predictor (BioClim), which is most related to the physiological characteristics of organisms, is used for vulnerability assessment. However, BioClim values are not provided other than the future period climate average values for each GCM for the Shared Socio-economic Pathways (SSPs) scenario. In this study, BioClim data suitable for domestic conditions was produced using 1 km resolution SSPs scenario detailed data produced by Rural Development Administration, and based on the data, a species distribution model was applied to mainly grow in southern, Gyeongsangbuk-do, Gangwon-do and humid regions. Appropriate habitat distributions were predicted every 30 years for the base years (1981 - 2010) and future years (2011 - 2100) of the Acer pictum subsp. mono. Acer pictum subsp. mono appearance data were collected from a total of 819 points through the national natural environment survey data. In order to improve the performance of the MaxEnt model, the parameters of the model (LQH-1.5) were optimized, and 7 detailed biolicm indices and 5 topographical indices were applied to the MaxEnt model. Drainage, Annual Precipitation (Bio12), and Slope significantly contributed to the distribution of Acer pictum subsp. mono in Korea. As a result of reflecting the growth characteristics that favor moist and fertile soil, the influence of climatic factors was not significant. Accordingly, in the base year, the suitable habitat for a high level of Acer pictum subsp. mono is 3.41% of the area of Korea, and in the near future (2011 - 2040) and far future (2071 - 2100), SSP1-2.6 accounts for 0.01% and 0.02%, gradually decreasing. However, in SSP5-8.5, it was 0.01% and 0.72%, respectively, showing a tendency to decrease in the near future compared to the base year, but to gradually increase toward the far future. This study confirms the future distribution of vegetation that is more easily adapted to climate change, and has significance as a basic study that can be used for future forest restoration of climate change-adapted species.

• Journal of Korean Society of Forest Science
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• v.111 no.1
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• pp.115-124
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• 2022

This study was conducted to obtain basic data that could help prevent damage caused by slow-moving landslides (land-creep). Specifically, the geological, topographic, and physical characteristics of land-creep were analyzed in Jiphyeon-myeon, Jinju-si. The first and second analyzed land-creeps occurred in 1982 and 2019, respectively. The area damaged in the second land-creep was about 11.5-fold larger than that damaged in the first land-creep. The dominant constituent rock in the land-creep area was sedimentary rock, which seems to be weakly resistant to weathering. The areas that collapsed due to land-creep were related to the presence of separated rocks between the bedding plane in the estimated activity surface over the slope direction and the vertically developed joint surface. Thus, surface water and soil debris were introduced through the gaps of separated rocks. Additionally, the areas collapsed due to the combination of the bedding plane and joint surface shale and sandstone showed an onion structure of weathered outcrop from the edge to inner part caused by weathering from ground water. Consequently, core stones were formed. The study area was a typical area of land-creep in a mountain caused by ground water. Land-creep was classified into convex areas of colluvial land-creep. The landslide-risk rating in the study area was classified into three and five classes. The flow of ground water moved to the northeast and coincided with the direction of the collapse. Soil bulk density in the collapsed area was lower than that in ridge area, which was rarely affected by land-creep. Thus, soil bulk density was affected by the soil disturbance in the collapsed area.