• Title/Summary/Keyword: 필터스트립

Search Result 3, Processing Time 0.055 seconds

Analyzing the Effectiveness of a Best Management Practice on Sediment Yields Using a Spatially Distributed Model (공간분포형 모델을 이용한 최적관리방안의 토사 유출 저감 효과에 관한 연구)

  • Lee, Taesoo
    • Journal of the Korean Geographical Society
    • /
    • v.52 no.1
    • /
    • pp.15-24
    • /
    • 2017
  • Management of non-point sources for water quality control practice is complicating but very important. Sediments mainly from croplands are prioritized in non-point source management due to the sediment attached phosphorous. In this study, flow and sediment yields are modeled in Oenam watershed located in Hwasun, Jeollanam-do, a upstream of Juam Lake. A spatially distributed model and GIS(Geographic Information System) data was used to find out hot spots of sediment yields, to analyze the effectiveness of filter strips, and to visualize the effectiveness. The impacts of filter strips was estimated on the reduction of flow and sediments at 17.2% and 46.4% respectively when the filter strips were installed in the sub-watersheds with the most serious sediment yields.

  • PDF

The Impacts of Biofuel Production on Water Quality and a Mitigation Methodology to Reduce the Impacts (바이오 연료 생산이 수질에 미치는 영향과 수질오염의 최소화 방안)

  • Lee, Tae-Soo
    • Journal of the Korean Geographical Society
    • /
    • v.46 no.1
    • /
    • pp.50-66
    • /
    • 2011
  • Biofuel crops and their economical benefits have been recently researched as one of the alternative energy sources. Very few studies, however, have brought an issue about the impacts of the new cropping on environment, especially water quality. Because biofuel cropping requires more crop production with more fertilizers for cost-effectiveness, water quality near the new crops as well as downstream is expected to be degraded. In this study, the impacts of biofuel crop production on water quality was estimated by scenarios between pre-biofuel cropping and post-biofuel cropping using the previously calibrated SWAT (Soil and Water Assessment Tool) model in a watershed in Texas, USA. Then, 30 meter filter strips were implemented on each biofuel ropland as a mitigation method. The economical and agricultural aspect and requirements of biofuel cropping was also previously investigated. The on-site impacts estimation showed that biofuel cropping increased about 250% to 1,150% of Total Nitrogen and about 100% to 1,100% of Total Phosphorous annually. The off-site estimation at the reservoir (entire watershed outlet) showed the annual increase of 40 to 50% for both Total Nitrogen and Total Phosphorous. The on-site effectiveness of filter strips was from 58.0% to 67.9% reduction for Total Nitrogen and 57.7% to 68.2% reduction for Total Phosphorous. The filter strips reduced 28.5% of Total Nitrogen and 29.4% of Total Phosphorous at the watershed outlet.

Design of Two-DOF Optimal Controller for Strip Gage and Tension Control of Cold Tandem Mills Using Reference Shaping Filter and Disturbance Observer (목표치 정형화 및 외란 관측기를 활용한 연속 냉간압연 시스템의 2-자유도 스트립 두께 및 장력 최적 제어기 설계)

  • Hong, Wan-Kee;Kang, Hyun-Seok;Hwang, I-Cheol
    • Transactions of the Korean Society of Mechanical Engineers A
    • /
    • v.36 no.2
    • /
    • pp.237-244
    • /
    • 2012
  • This paper studies the design of a two-DOF optimal controller for the strip gauge-tension of cold tandem mill processes, that uses a reference shaping filter and a disturbance observer. First, a mathematical model of the strip gauge and tension system is constructed using the gauge meter equation and Hooke's law, respectively. Next, a two-DOF controller considering of a feedforward controller and a feedback controller is designed. The former is based on the reference shaping filter and the disturbance observer, and the latter is based on the ILQ optimal control algorithm. Finally, it is shown through a computer simulation that the proposed optimal controller is able to improve the strip gauge accuracy and the tension variation more than the conventional MV-AGC controller.