• 제목/요약/키워드: Duration Curve

검색결과 443건 처리시간 0.025초

추령천 유역의 유황별 유달율 계산 (Pollutant Load Delivery Ratio for Flow Duration at the Chooryeong-cheon Watershed)

  • 김영주;윤광식;손재권;최진규;장남익
    • 한국농공학회논문집
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    • 제52권4호
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    • pp.19-26
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    • 2010
  • To provide the basic information for the water quality management of the Sumjin River Basin, delivery ratios for flow duration were studied. Using the day-interval data set of discharge and water quality observed from the Chooryeong-cheon watershed, the flow-duration and discharge-load relation curves for the watershed were established, then the load-duration curve was constructed. Delivery ratios for flow duration were also developed. Delivery ratios showed wide variation according to flow conditions. In general, delivery ratio of high flow condition showed higher value reflecting nonpoint source pollution contribution from the forest dominating watershed. To resolve this problem, a regression model explaining the relation between flow rate and delivery ratio was suggested. The delivery ratios for different flow regime could be used for pollutant load estimation and TMDL (Total maximum daily load) development.

뇌졸중 환자의 직선보행과 곡선보행 시 시공간적 변수의 비교 (Comparison of Spatiotemporal Parameters during Straight and Curve Walking for Patients with Stroke)

  • 최보라;우영근;황수진
    • PNF and Movement
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    • 제17권1호
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    • pp.129-136
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    • 2019
  • Purpose: This study is a comparison of spatiotemporal parameters between straight and curved walking in individuals with chronic hemiparetic stroke, investigating whether those patients can adapt their walking according to task demands and environmental changes. Methods: Twenty-eight patients who diagnosed with their first stroke at least six months prior to this study were recruited. They were measured for spatiotemporal parameters in three different walking conditions: straight walking, walking with an inner curve to the more-affected leg, and walking with an inner curve to the less-affected leg. This study also measured secondary clinical factors, such as the timed up-and-go test, the trunk impairment scale, and the dynamic gait index. The statistical methods for the three different walking conditions, using the averaged value of each condition, was repeated measures ANOVA. Results: The difference in cadence was statistically significant when comparing straight walking, walking with an inner curve to the more-affected leg, and walking with an inner curve to the less-affected leg. Swing duration (%) was also a statistically significant difference between straight walking and walking with an inner curve to the more-affected leg. However, differences in other spatiotemporal parameters were not statistically significant among the three conditions. Conclusion: The results of this study suggest that stroke survivors could adapt their walking according to straight and curved walking conditions, although cadence and swing duration were different between straight and curved walking groups.

누가분포함수를 활용한 강우강도식의 국내 적용성 평가 (Application of Intensity-Duration-Frequency Curve to Korea Derived by Cumulative Distribution Function)

  • 김규태;김태순;김수영;허준행
    • 대한토목학회논문집
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    • 제28권4B호
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    • pp.363-374
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    • 2008
  • 국내에서 수공구조물의 설계를 위한 확률강우량을 산정하기 위해서 널리 사용되는 강우강도식은 주로 회귀분석을 적용한 형태가 일반적이지만, 본 연구에서는 각 지점별 적정확률분포형의 누가분포함수를 활용하여 강우강도식의 형태를 결정하고, 매개변수는 유전자알고리즘을 적용하여 추정하는 강우강도식을 제안하고자 한다. 기존에 사용하던 강우강도식과의 정확도 비교를 위하여 기상청 22개 지점에 대한 재현기간, 지속기간별 평균제곱근오차, 평균제곱근 상대오차를 검토한 결과 누가분포함수를 활용한 강우강도식이 더 높은 정확도를 가짐을 보였으며, 또한, 최근의 집중호우에 대한 영향을 살펴보기 위하여 2006년 까지의 강우자료를 이용하여 기존의 회귀식에 의한 방법과 누가분포함수를 활용한 경우의 결과값을 비교한 결과 이 경우에도 누가분포함수를 활용한 강우강도식의 정확도가 더 높음을 알 수 있었다. 결과적으로 본 연구에서 제안된 누가분포함수를 활용한 강우강도식은 기존의 회귀분석을 활용한 강우강도식보다 정확도면에서 우수하다고 할 수 있으며, 국내에 충분히 적용가능한 형태의 강우강도식이라고 판단된다.

유역모형을 이용한 비점배출계수 적용성 평가 (Evaluation of Applicability for Nonpoint Discharge Coefficient using Watershed Model)

  • 이은정;김태근
    • 환경영향평가
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    • 제21권3호
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    • pp.339-352
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    • 2012
  • Total maximum daily load have been implemented and indicated that nonpoint discharge coeffients in flow duration curve were 0.50 of Normal flow duration ($Q_{185}$) and 0.15 of low flow duration($Q_{275}$). By using SWAT, nonpoint discharge coefficients are studied with the conditions of the instream flow and the rainfall in two study areas. The nonpoint discharge coefficient average of BOD and TP for normal flows duration in 3 years are 0.32~0.36 and 0.28~0.31. For the low flow duration, the nonpoint discharge coefficient avergae of BOD and TP were 0.10~0.12 and 0.10~0.11. These are lower than the coefficients of total maximum load regulation. There are big differences between one of regulation and one of SWAT for the normal flow duration. With the consideration of rainfall condition, the nonpoint discharge coefficient of flood flow duration are influenced on the amount of rainfalls. However, the nonpoint discharge coefficients of normal flow duration and low flow duration are not effected by the rainfall condition. Since the spatial distribution and geomorphological characteristics could be considered with SWAT, the estimation of nonpoint discharge coefficient in watershed model is better method than the use of the recommended number in the regulation.

탐색곡선법과 WASP-IV 모형을 이용한 국내 적정 전원구성 분석 (Generation Mix Analysis based on the Screening Curve and WASP-IV Techniques)

  • 장세환;박종배;노재형
    • 전기학회논문지
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    • 제61권4호
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    • pp.534-541
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    • 2012
  • This paper tries to elicit an optimal generation mix of Korea. Two approaches, using the screening curve method and taking advantage of a generation expansion planning tool, WASP-IV, are applied in getting the mix. The data used in this study is based on the 5th basic plan for long-term electricity supply and demand. The Load Duration Curve, that is needed for applying Screening Curve Method(SCM), is made based on the load profile in 2010. In our using SCM, the nuclear plant's operation characteristic, carbon emission cost and spinning reserve are considered. In using WASP-IV to get the adequate generation mix, the base and target demand forecasts in the 5th basic plan are used and the carbon emission cost is also considered. In this paper, It introduces the domestic adequacy generation mix in 2024 though SCM and WASP-IV.

Final Settlement Prediction Methods of Embankments on Soft Clay

  • Lee, Dal-Won;Lim, Seong-Hun
    • 한국농공학회지
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    • 제42권
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    • pp.68-77
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    • 2000
  • Analyses, in which load was regarded as instant load and gradual step load, respectively, were performed with data measured on a gradually loaded field, and the results were inspected to find the effect of load conditions, and the final settlements which were predicted by Hyperbolic, Tan's, Asaoka's, and Monden's methods were compared with each other. Settlement curves in which load was regarded as instant load and gradual step load being to coincide at twice the time of duration of embankment. On the ground installed vertical drain, from the results of Hyperbolic, Tan's, Asaoka's, Monden's, Curve fitting I, and Curve fitting II (simple, carrillo) methods it was concluded that Asaoka, Curve fitting I, and Curve fitting II methods are reliable for prediction final settlement with back analysis.

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HSPF를 이용한 비점오염원 삭감에 따른 효과 분석 (Assessing Impact of Reduction of Non-Point Source Pollution by BASINS/HSPF)

  • 배다혜;하성룡
    • 환경영향평가
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    • 제20권1호
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    • pp.71-78
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    • 2011
  • This paper aims to assessing impact of reduction of non-point source pollution in the Bokha Stream watershed. The BASINS/HSPF model was calibrated and verified for water flow and water qualities using Total Maximum Daily Load 8days data from 2006 to 2007. Accuracy of the BASINS/HSPF models in simulating hydrology and water quality was compared and there were somewhat differences of statistical results, but water flow and water quality were simulated in good conditions over the study period. The applicability of models was tested to evaluate non-point source control scenarios to response hydrology and water quality in the Bokha stream using various measures which include BMPs approach and change of landuse. The evaluation of reduction of non-point source pollution was developed using load-duration curve. Despite strong reduction of non-point source, there are not satiated target quality at low flow season.

도시유역의 하천유지용수 산정에 관한 연구 (A Study on the Estimation of River Management Flow in Urban Basin)

  • 이영화
    • 한국환경과학회지
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    • 제5권3호
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    • pp.377-385
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    • 1996
  • This study aims at the estimation of a river management flow in urban basin analyzing Sinchun basin to be the tributary of Kumho river basin. The river management flow has to satisfy a low flow as natural flow and an environmental preservation flow estimated by a dilution flow to satisfy a target water quality in drought flow. Therefore for the estimation of a river management flow in Sinchun in this study, first Tank model as a basin runoff model estimates a low flow, a drought flow from a flow duration curve in Sinchun, second QUAL2E model as water quality model simulates water quality in Sinchun and estimates environmental preservation flow to satisfy a target water qua%its, BOD 8 mg/l by a dilution flow derived from Kumho river, Nakdong river and around water. And the river management flow is estimated by addition of a use flow and a loss flow to more flow between a low-flow and an environmental preservation flow.

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