• Journal of the Korean Magnetics Society
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• v.22 no.2
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• pp.33-36
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• 2012

We propose a simple prescription for resolving the general-$N$ problem existing in the old-fashioned mixed-radix fast Fourier transformation FORTRAN subroutine by Singleton in 1968. After a brief investigation on the problem, we discuss our prescription with the worst case analysis within the dynamical allocation. The analysis reveals that our implementation is superior, at least for multi-variate data set, than previously proposed data copying methods.

• Membrane Journal
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• v.26 no.5
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• pp.365-371
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• 2016

A numerical analysis was performed for a separation of carbon dioxide and methane using 2-staged, membrane process where two polysulfone hollow fiber membrane modules were connected to provide both the methane concentration richer than 95% and the recovery higher than 90% using the recycled flows. The Compaq Visual Fortran 6.6 software was utilized for the numerical simulation. Both the methane concentration and the recovery % of methane could be successfully predicted as the function of the operating conditions. As the feed pressure, the methane concentration, and the flow rate increase, the methane concentration in a product is also found to increase and the recovery of methane is found to decrease.

• Journal of Korea Water Resources Association
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• v.42 no.12
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• pp.1103-1111
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• 2009

This study derived the analysis results of alternatives for integrated watershed management under urbanization and climate change scenarios. Climate change and urbanization scenarios were obtained by using SDSM (Statistical Downscaling Method) model and ICM (Impervious Cover Model), respectively. Alternatives for the Anyangcheon watershed are reuse of wastewater treatment plant effluent, and redevelopment of existing reservoir. Flow and BOD concentration duration curves were derived by using HSPF (Hydrological Simulation Program - Fortran) model. As a result, low flow ($Q_{99},\;Q_{95},\;Q_{90}$) and BOD concentration ($Q_{10},\;Q_5,\;Q_1$) were very sensitive to the alternatives comparing to high flow($C_{30},\;C_{10},\;C_1$). Although urbanization makes the hydrological cycle distorted, effective alternatives can reduce its damage. The numbers of days to satisfy the instreamflow requirements and target water quality were also sensitive to urbanization. This result showed that the climate change and urbanization should be considered in the water resources/watershed and environmental planning.

• Journal of Korean Society on Water Environment
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• v.26 no.2
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• pp.268-278
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• 2010

This study derived the effectiveness analysis results of construction of wastewater treatment plant under climate change scenarios. Canadian Global Coupled Model (CGCM3) was used and A1B and A2 of Special Report on Emission Scenario (SRES) were selected. Regional climate change data for this application were downscaled by using Statistical Downscaling Model (SDSM) and the flow and BOD concentration durations were obtained by using Hydrological Simulation Program - Fortran (HSPF). The criteria for low flow and water quality were chosen as $Q_{99}$, $Q_{95}$, $Q_{90}$ and $C_{30}$, $C_{10}$, $C_1$. The numbers of days to satisfy the instreamflow requirements and target BOD concentration were also added to the criteria for comparison. As a results, small wastewater treatment plant improved the water cycle due to the increase of low flow and the decrease of BOD concentration. But climate change affected the reduction of effectiveness significantly. Especially in case of construction of small waste water treatment plant in the upstream region, it is necessary to take climate change impact into consideration since it is usually related to the low flow and the water quality of the stream.

• Journal of The Korean Society of Agricultural Engineers
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• v.52 no.6
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• pp.39-48
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• 2010

Sediment yields from Imha watershed were simulated during 1993-2008 using Hydrologic Simulation Program-Fortran (HSPF). Using observed daily stream flow for 2004-2008 and hourly suspended solid concentration for three events during 2006, HSPF was calibrated and validated at the sites of Imha and Youngyang for stream flow and Dongchun and Jangpachun for sediment yield. The calibration and validation results represented high model efficiency for simulating daily stream flow and hourly suspended solid. The determination coefficients of calibration and validation were 0.90 and 0.81 for daily stream flow, and 0.91 and 0.86 for monthly stream flow, respectively. Based on model tolerances for calibration and validation of stream flow, HSPF performance for simulating stream flow represented 'very good'. The determination coefficients of calibration and validation were 0.94-0.96 and 0.95 for hourly sediment yields, respectively. The average yearly sediment yield during 1993-2008 was 122,290 ton/year and most of sediment yield (77 % of total yield) were generated from June to August. The calibrated HSPF simulated well the movement of water and eroded soil within Imha watershed.