폐쇄 해역의 자정능력 평가를 위한 모델 연구

박정은 ( Park Jeong Eun ),박석순 ( Park Seog Sun ) 한국물환경학회 2003 한국물환경학회지 Vol.19 No.3

This paper presents the results of modeling study to predict the flushing rate which is an indicator of self-purification capacity in a coastal embayment. They study was performed on the Mokpo harbor system and surrounded coastal area, utilizing the RMA-/RMA-4 models developed by U.S.Army Corps of Engineers. Two dimensional finite element grides(4,133 nodes and 1,296 elements) were constructed on the study area, based on the system geometry. Tidal flow and mass transport phenomena were simulated and validate against the measured tidal heights and water quality data. Model validation results showed reasonable agreements with the field measurements. Utilizing the validated models, tidal currents and water quality distribution were predicted spatially as well dynamically. The flushing rate was estimated from the water quality change within the embayment due to tidal movement. Two different flushing rates(with and without biochemical decay) were compared in order to examine the contribution of biochemical degradation to the self-purification. The flushing rate was computed at six locations during neap and spring tides. The results indicated that the flushing rates were significantly different by tidal pattern within the study area(neap and spring tides) as well as by locations. The biochemical degradation, however, does not cause a discernible impact on the flushing rate, indicating that tidal movement plays the major role in self-purificaton of pollution loads. From this study, it was concluded that the discharge location and time of pollution loads should be important parameters to be considered for the effective management of water quality in a coastal embayment.

습지 퇴적물에서 비소의성상과 이동 모의에 관한 수학적 모형

왕수균 ( Wang Su Gyun ),박석순 ( Park Seog Sun ) 한국하천호수학회 2003 생태와 환경 Vol.36 No.4

The fate and transport of many trace metals, metalloids, and radionucldes in porous media is closely linked to the biogeochemical reactions that occur as a result of organic carbon being sequentially degraded by different microorganisms using a series of terminal electron acceptors. The spatial distribution of these biogeochemical reactions is affected by processes that are often unique and/or characteristic to a specific environment. Generic model formulations have been developed and applied to simulate the fate and transport of arsenic in two hydrologic settings, permanently flooded freshwater sediments, namely non-vegetated wetland sediments and vegetated wetland sediments. The key physical processes that have been considered are sedimentation, effects of roots in biogeochemistry, advective transport, and differences in mixing processes. Steady-state formulations were applied to the sedimentary environments. Results of numerical simulations show that these physical processes significantly affect the chemical profiles of different electron acceptors, their reduced species, and arsenate as well as arsenite that will result from the degradation of an organic carbon source in the sediments. Even though specific biological transpormations are allowed to proceed only in zones where they are thermodynamically favorable, the results show that mixing as well as abiotic reactions can make the profiles of individual electron acceptors overlap and/or appear to reverse their expected order.

비모수 통계기법을 이용한 낙동강 수계의 수질 장기 경향 분석

김주화 ( Kim Ju Hwa ),박석순 ( Park Seog Sun ) 한국물환경학회 2004 한국물환경학회지 Vol.20 No.1

The long-term trend analyses of water qualities were performed for 49 monitoring stations located in Nakdong River. Water quality parameters used in this study are the monthly data of BOD(Biological Oxygen Demand), TN(Total Nitrogen) and TP(Total Phosphorus) measured from 1990 to 1999. The long-term trends were analyzed by Seasonal Mann-Kendall Test and Locally WEighted Scatter plot Smoother(LOWESS). Nakdong river was divided into four subbasins, including upstream waershed, midstream watershed, western downstream watershed and eastern downstream watershed. The results of Seasongal Mann-Kendall Test indicated that there would be no trends of BOD in upstream waershed, western and eastern downstream watershed. Trends of BOD were downward in midstream watershed. For TN and TP, there were upward trends in all of watersheds. But LOWESS curves suggested that BOD, TN and TP concentrations generally increased between 1990 and 1996, then resumed decreasing.

오염총량관리를 위한 의사결정 지원시스템 적용

이혜영 ( Lee Hye Yeong ),박석순 ( Park Seog Sun ) 한국물환경학회 2004 한국물환경학회지 Vol.20 No.2

A decision support system, Watershed Analysis Risk Management Framework(WARMF), was applied to the Kyungan Stream watershed, a tributary of Lake Paldang, for calculation of total maximum daily loads(TMDL). The WARMF system was developed by Systech Engineering, USA, and has been successfully used in several watersheds, for TMDL studies. The study area was divided into 14 sub-basins, based on digital elevation model(DEM). The integrated watershed and stream model of WARMF was validated by flow and BOD data measured during the year of 1999. There were reasonable agreements between model results and field data, both in water flow and BOD. The validated Kyungan WARMF was extensively utilized to study the quantitative relationship between waste loads and receiving water quality. Based on TMDL guideline at Paldang Lake and Kyungan Stream, the water quality criterion were set to be 3.0㎎/L, 3.5㎎/L, and 4.0㎎/L at the watershed outlet. The allowable waste loads of BOD, both from point and non-point sources, were determined at each water quality criterion. From this study, it was concluded that the WARh4F provided several advantages over the conventional application of watershed and stream models for TMDL study, such as time variable simulations, multiple possible soutions, and reduction loads for goal water quality, etc.

부하함수 모델을 이용한 경안천 유역의 월별 인,질소 부하량 산정

유혜진 ( Yu Hye Jin ),박석순 ( Park Seog Sun ) 한국물환경학회 2003 한국물환경학회지 Vol.19 No.4

The GWLF (Generalized Watershed Loading Functions) model was applied to the Kyungan stream watershed to estimate monthly nutrient loads. Based on the model structure, the Kyungan stream watershed was divided into 360 grid cells. Each cell had the size of 1,200×1,200 m. The model input parameters were obtained from Digital Elevation Model, Landsat TM imagery, soil map, and published literature on the study area. The model predictions were compared with the field measurements in stream flow as well as in nutrient loads. In most cases, there were reasonable agreements between measurements and predictions, where the coefficients of determination for stream flow, TN, and TP were 0.90, 0.83, and 0 73, respectively. The validated model was used to analyze the seasonal contributions of nutrients according to the types of sources. It was estimated that 7% of TN loads would originate from point sources, 49% from non-point sources and 44% from ground water during rainy season(August), while loads from non-point sources and ground water would be very low during dry season. 46 % of the total annual TN loads was from ground water, 30 % from point sources and 24 % from non-point sources. For land use loads, 14% of total loads were from dry field, 4% from paddy field, 3% from forest and 1% from residential. The contributions of TP loads were more than 90% for non-point sources in August, rainy season, while that of TP loads from non-point sources is very low in dry season. Of the total loads, loads from point sources were 44% and loads from non-point sources were 56% in the annual TP loads. For land use loads, 35% of total loads were from dry field, 11% from paddy field, 7% from forest and 4% from residential. Because nutrients from non-point sources are loaded in rainy season concentrically, appropriate action should be taken for this. In TN loads, contribution of loads from ground water was estimated very high. The results of GWLF model showed reasonable agreement with observed TN, TP loads in Kyungan stream watershed. In summary the GWLF model can be used to quantity non-point source loads effectively.

로그선형모델을 이용한 팔당호 유입지류 수질의 연속성 시뮬레이션과 경향 분석

나은혜 ( Na Eun Hye ),박석순 ( Park Seog Sun ) 한국하천호수학회 2003 생태와 환경 Vol.36 No.3

Two types of statistical models, simple and multivariate log linear models, were studied for continuity simulation and trend analysis of water qualities in incoming flows to Lake Paldang. Water quality is a function of one independent variable(flow) in the simple log linear model, and of three different variables (flow, time, and seasonal cycle) in multivariate model. The independent variables act as surrogate variables of water quality in both models. The model coefficients were determined by the monthly data. The water qualities included 5-day Biochemical Oxygen Demand(BOD_(5)), Total Nitrogen (TN), and Total Phosphorus(TP) measured from 1995 to 2000 in the South and the North branches of Han River and the Kyoungan Stream. The results indicated that the multivariate model provided better agreements with field measurements than the simple one in all attempted cases. Flow dependency, seasonality, and temporal trends of water quality were tested on the determined coefficients of the multivaariate model. The test of flow dependency indicated that BOD concentrations decreased as the water flow increased. In TN and TP concentrations, however, there were no discernible flow effects. From the temporal trend analyses, the following results were obtained: 1) no trends on BOD at all three upstreams, 2) increase on TN at the South Branch and the Kyoungan Stream, 3) decrease on TN at the North Branch, 4) no trends on TP at the North and the South Branches and 5) increase on TP at the Kyoungan Stream by 3 to 8% per years. The seasonality test showed that there were significant seasonal variations in all three water qualities at three incoming flows.

역진자시스템의 계수도법을 이용한 제어기 설계

박석순,이상석 대구미래대학 2000 論文集 Vol.18 No.1

The Coefficient Diagram Method (CDM) is an algebraic approach over polynomial ring in the parametric approach space. The purpose of this paper is to explain the basic theory of the CDM and to design the 2/2 order controller for the Inverted Pendulum system by CDM. We also derived the dynamic equation of the Inverted Pendulum system. The simulation result shows the robustness of the controller designed by CDM with respect to the moment of inertia perturbation.