• 한국농공학회논문집
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• 제55권4호
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• pp.121-131
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• 2013

This study focused on the sediment reduction effects of VFS (vegetative filter strip) systems for the general characteristics of uplands in Korea. General conditions of upland fields were investigated through national scales of annual agricultural statistics. 7-15 % of slope with loam soil was the dominant types of uplands, and the hydrologic soil group feature usually belong to Type B. The common sizes of uplands were bigger than 0.1 ha and less than 0.2 ha, and 86.2 % of them account for less than 1.0 ha. With this information, 0.1 ha, 0.5 ha, and 1.0 ha of uplands with various shapes and 7-15 % of slopes were considered for the VFS system simulations. 20 mm, 40 mm, and 100 mm of daily precipitation were applied. As a result, the trapping efficiencies of VFS systems were obtained 37.4~100 % for 7 % slope and 18.1~98.0 % for 15 % slope of the less than 1.0ha of uplands. As rainfall increased, sediment loads also increased with slope and slope length increase. Also as size and slope of uplands and slope length increased with VFS length decrease, the trapping efficiency decreased for the same amount of rainfall. The optimum lengths of VFS systems for the givien upland conditions were suggested based on the modelling results with condition of VFS length less than 20 % of upland areas.

• 한국식품영양과학회지
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• 제45권6호
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• pp.865-871
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• 2016

본 연구에서는 렌틸콩 앙금을 만들어 일반성분을 분석하고, 렌틸콩 앙금의 비율(0%, 25%, 50%, 75%)을 다르게 첨가하여 양갱을 제조한 후, 수분함량, pH, 당도, 색도, 조직감, 총 폴리페놀 함량, DPPH 라디칼 소거 활성을 평가하고 기호도 평가를 시행하였다. 렌틸콩 앙금의 수분함량은 15.63%, 조단백질은 17.31%, 조회분은 0.92%, 조지방은 0.31%, 건조수율은 54.25%를 나타냈다. 렌틸콩 앙금을 첨가한 양갱의 수분함량은 렌틸콩 앙금 첨가량이 증가할수록 42.83~65.17 %로 유의적으로 증가했고 당도는 3.40에서 1.20으로 감소하였으나, pH는 유의적인 차이를 보이지 않았다. 색도는 렌틸콩 앙금 첨가량이 증가할수록 명도를 나타내는 L값은 유의적으로 감소하였고, 적색도를 나타내는 a값과 황색도를 나타내는 b값은 유의적으로 증가하였다. 조직감은 렌틸콩앙금의 첨가량이 증가함에 따라 탄력성, 검성, 씹힘성이 유의적으로 감소하는 경향을 보였으며 경도와 응집성은 유의적인 차이를 보이지 않았다. 총 폴리페놀 함량과 DPPH 라디칼 소거 활성은 렌틸콩 앙금 첨가량이 증가할수록 유의적으로 높은 값을 보였다. 기호도 평가 결과 맛, 질감, 전체적인 기호도에서 25% 첨가군이 유의적으로 높은 점수를 받았다. 이상의 결과를 종합하여 볼 때 렌틸콩 앙금을 25% 첨가하여 양갱을 제조한다면 양갱의 관능적 품질을 최대한 유지하면서 기능성 식품으로 소비자의 욕구를 충족시킬 수 있을 것이다.

• 한국농공학회지
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• 제22권4호
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• pp.108-114
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• 1980

A deterministic conceptual erosion model which simulates detachment, entrainment, transport and deposition of eroded soil particles by rainfall impact and flowing water is presented. Both upland and channel phases of sediment yield are incorporated into the erosion model. The algorithms for the soil erosion and sedimentation processes including land and crop management effects are taken from the literature and then solved using a digital computer. The erosion model is used in conjunction with the modified Kentucky Watershed Model which simulates the hydrologic characteristics from watershed data. The two models are linked together by using the appropriate computer code. Calibrations for both the watershed and erosion model parameters are made by comparing the simulated results with actual field measurements in the Four Mile Creek watershed near Traer, Iowa using 1976 and 1977 water year data. Two water years, 1970 and 1978 are used as test years for model verification. There is good agreement between the mean daily simulated and recorded streamflow and between the simulated and recorded suspended sediment load except few partial differences. The following conclusions were drawn from the results after testing the watershed and erosion model. 1. The watershed and erosion model is a deterministic lumped parameter model, and is capable of simulating the daily mean streamflow and suspended sediment load within a 20 percent error, when the correct watershed and erosion parameters are supplied. 2. It is found that soil erosion is sensitive to errors in simulation of occurrence and intensity of precipitation and of overland flow. Therefore, representative precipitation data and a watershed model which provides an accurate simulation of soil moisture and resulting overland flow are essential for the accurate simulation of soil erosion and subsequent sediment transport prediction. 3. Erroneous prediction of snowmelt in terms of time and magnitute in conjunction with The frozen ground could be the reason for the poor simulation of streamflow as well as sediment yield in the snowmelt period. More elaborate and accurate snowmelt submodels will greatly improve accuracy. 4. Poor simulation results can be attributed to deficiencies in erosion model and to errors in the observed data such as the recorded daily streamflow and the sediment concentration. 5. Crop management and tillage operations are two major factors that have a great effect on soil erosion simulation. The erosion model attempts to evaluate the impact of crop management and tillage effects on sediment production. These effects on sediment yield appear to be somewhat equivalent to the effect of overland flow. 6. Application and testing of the watershed and erosion model on watersheds in a variety of regions with different soils and meteorological characteristics may be recommended to verify its general applicability and to detact the deficiencies of the model. Futhermore, by further modification and expansion with additional data, the watershed and erosion model developed through this study can be used as a planning tool for watershed management and for solving agricultural non-point pollution problems.

• 한국지반환경공학회 논문집
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• 제18권6호
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• pp.21-30
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• 2017

본 연구에서는 도심지 토사재해 예비중점관리 대상지역 중 충주시 안림동, 대전광역시 부사동, 안동시 신안동 3개 연구지역을 선정하여 지반특성을 분석하였다. 연구지역별 특성(수관밀도, 뿌리점착력, 강우특성, 토질특성)을 이용하여 지반특성 간의 상관관계를 고찰하고, 토사재해 예측 모델링을 통해 위험지역을 예측하였다. 토사재해 위험지 예측 모델의 비교 분석을 위하여 산지토사재해 예측프로그램(LSMAP), Stability Index MAPping(SINMAP), 산림청의 산사태위험지도(LHMAP)를 활용하였으며, 토사재해 예측에 적합한 프로그램을 검토하였다. 토사재해 위험도 예측결과 일반적으로 사용되고 있는 SINMAP의 경우 과다한 범위를 위험지역으로 예측하고, 산림청 산사태위험지도(LHMAP)의 경우는 예측지역이 가장 적게 산정되었으며, LSMAP은 SINMAP 및 LHMAP의 중간 정도 범위의 지역을 위험지역으로 예측하였다. 이러한 예측 결과의 차이는 LSMAP이 비교된 두 모델에 비해 분석 매개변수가 비교적 다양하고, 공학적이기 때문인 것으로 판단되며 보다 정밀한 예측이 가능하다는 것을 알 수 있었다.

• 한국농공학회:학술대회논문집
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• 한국농공학회 2001년도 학술발표회 발표논문집
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• pp.324-329
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• 2001

Sediment yields from the reservoir watershed areas and raising of the spillway crest for the agricultural reservoir capacity enlargement were investigated and analysed through the 21 pilot reservoirs, have irrigated areas 200has. and over in the Kyoungpook province. In these studies, (1), the correlation analysis between various watershed characteristics and annual specific sediment yields were derived and (2), the excess effective reservoir capacity of the over 0.5m above the spillway crest could be estimated. In brief, catchment area should strongly be correlated with the annual specific sediment yields (R=0.90), the other side, average slope of the main stream is less than catchment area. The excess effective capacity of reservoir enlargement by the raising of spillway crest at 0.5m-height was resulted 12.1% of increasing capacity compare with the original reservoir capacity.

• 산업기술연구
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• 제19권
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• pp.391-402
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• 1999

The numerical model predicting the behaviours of submerged mound constructed by dredged material is developed in this paper. The model is based on the Bailard's sediment transport formula, Stokes' second-order wave theory and the sediment balance equation. Nonlinear partial differential equation which is the same form as convection-dispersion equation which represents change of bed section can be obtained by substituting sediment transport equation for equation of sediment conservation. By this process, the analytical solution by which the characteristic of the behaviours of submerged mound can be estimated is derived by probably combining the convention coefficient and the dispersion coefficient governing the behaviours of submerged mound and the probability density function representing the wave characteristics. The validity of the analytical solution is verified by comparing the analytical solution which is assumed to estimate the movement rate submerged mound by bed-load with the field data of the past and its characteristic is analyzed quantitatively by obtaining the mean of the dispersion coefficient representing the extent of the decrease rate of the submerged mound height.

• 물과 미래
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• 제13권4호
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• pp.33-40
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• 1980

해안지형 변화의 주원인인 부유사에 대한 연구가 이론적·실험적으로 다소 있었으나 그의 성질을 완전히 해석하기에는 상당한 난점이 있다. 그 이유는 자연상태의 변형인자들이 너무 많고 서로 복합적으로 연합되어 있어 실험실내에서는 실험할 때 고려되어야 할 많은 인자들의 제약이 뒤따르며, 실제 해안에서의 실측은 많은 인력 및 경비와 시간적·공간적 제약이 수반되기 때문이다. 본 연구는 미소진폭파에 의한 비정상 확산방정식을 해석하여 부유사 농도의 시간적 변화와 연직농도분포 및 침강속도의 영향을 밝힘으로써 부유사의 기초적 성질을 규명하는데 목적이 있다.

• 한국농공학회:학술대회논문집
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• 한국농공학회 2000년도 학술발표회 발표논문집
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• pp.365-370
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• 2000

Sea dike construction for the tidal flat reclamation works in estuary and coast may change the characteristics of tidal motion and wave conditions in the region. In turn, a new hydraulic condition provides the impacts on sediment transport pattern and forms a new morphological environment. Also, morphological changes during the closure works of sea dike are closely related with a safy of sea dike. Therefore, the prediction of morphological changes is required secure the safe closure work and the economic design of sea dikes. To investigate morphological changes due to sea dike construction, hydrodynamic changes of tides and waves have to be evaluated, then sediment transport and sea bottom changes are computed. Mathematical modelling is required for representation of interrelation of tidal motion, wave and sediment transport. In this study, numerical model MORSYS is applied to compute the hydrodynamics and morphological changes around the closure gap for Saemankuem dike. This model allows a flexible integration of the module for waves, currents, sediment transport and bottom changes.

• Environmental Engineering Research
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• 제18권4호
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• pp.259-265
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• 2013

This study was conducted June 2011 at Gamo Lagoon, after tsunami of March 2011, to estimate food sources and utilization. The results show that the tsunami affected the sediment properties by changing the physical environmental alterations. The fatty acids of the gut content of Nuttallia olivacea mostly comprised the same organic matter found in the sediment. Fatty acids in the tissues showed mainly diatoms, bacteria, and dinoflagellates. That is, most of the food sources (i.e., diatoms, bacteria, dinoflagellates, macroalgae, and terrestrial organic matter) probably pass through the digestive system unharmed; however, terrestrial organic matter, which is refractory to biochemical degradation, indicated a different assimilation trend between the gut content and the tissue. This result suggests that input of labile organic matter from the sediment may control selective metabolism in N. olivacea. From these results, although the physical environment of sediment characteristics by tsunami changed, the food utilization of N. olivacea suggested a better assimilation of selected components from the gut content, irrespective of physical alteration.

• 물과 미래
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• 제11권1호
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• pp.47-58
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• 1978

This study is concerned with the analysis of the formulas which give both the quantity of the total, suspended and bed loads as functions of stream and sediment characteristics. The numerical analysis of sediment discharge formulas is described and the computer program for the following 4 formulas are developed; (1) Einstein's Formula (2) Toffaleti's Formula (3) Brown's Formula (4) Kikkawa's Formula In the analysis of these formulas, the hydraulic data of the river in the downstream of the Han River are used, and these formulas have been tested by application and comparison with observed data and the results computed by the computer. In these methods and procedures, the most satisfactory and convenient formula is selected. The design and planning of the river channel regulation works are determined by computing the river bed variation by using the sediment discharge computed from the selected formula.