• Animal cells and systems
• /
• v.8
• /
• pp.29-29
• /
• 2004

• Journal of Korean Society of Environmental Engineers
• /
• v.27 no.8
• /
• pp.813-821
• /
• 2005

This paper presents a modeling study of thermal dynamics and turbid current in the Obong Lake, Kangreung. The lake formed by the artificial dam in 1983 for agricultural water supply, is currently under consideration of reconstruction in order to expand the volume of reservoir for water supply and flood control in downstream area. The US Army Corps of Engineers' CE-QUAL-W2, a two-dimensional laterally averaged hydrodynamic and water quality model, was applied to the lake after reconstruction as well as the present lake. The model calibration and verification were conducted against surface water levels and temperature of the lake measured during the years of 2001 and 2003. The model results showed a good agreement with fold measurements both in calibration and verification. Utilizing the validated model, an impact of dam reconstruction on vertical temperature and hydrodynamics were predicted. The model results showed that steep temperature gradient between epilimnion and hypolimnion would be formed during summer, along with extension of cold deep water after reconstruction. During winter and spring seasons, however, the vertical temperature profiles was predicted to be quite similar both before and after reconstruction. This results indicated that thermal stratification would become stronger during summer and stay longer after dam reconstruction. From the examination of predicted water movements, it was noticed that the upstream turbid current would infiltrate into the interface between metalimnion and hypolimnion and then suspended solids would slowly settle down to the bottom before reconstruction. After reconstruction, however, it was shown that the upstream turbid current would stay longer in metalimnion with similar density due to strong stratification. The model also predicted that dam reconstruction would make suspended solids near the dam location significantly decrease.

• Korean Journal of Remote Sensing
• /
• v.20 no.3
• /
• pp.163-173
• /
• 2004

The objective of this study is to develop a method to generate micro-relief digital elevation model (DEM) data of the tidal mudflats using multi-temporal Landsat Thematic Mapper (TM) data. Field spectroscopy measurements showed that reflectance of the exposed mudflat, shallow turbid water, and normal coastal water varied by TM band wavelength. Two sets of DEM data of the inter-tidal mudflat area were generated by interpolating several waterlines extracted from multi-temporal TM data acquired at different sea levels. The waterline appearing in the near-infrared band was different from the one in the middle-infrared band. It was found that the waterline in TM band 4 image was the boundary between the shallow turbid water and normal coastal water and used as a second contour line having 50cm water depth in the study area. DEM data generated by using both TM bands 4 and 5 rendered more detailed topographic relief as compared to the one made by using TM band 5 alone.

• Proceedings of the Korea Water Resources Association Conference
• /
• 2019.05a
• /
• pp.159-159
• /
• 2019

In this study, the simulation of sediment deposition at Sangju weir reservoir, South Korea, was carried out using artificial neural networks. The ANNs have typically been used in water resources engineering problems for their robustness and high degree of accuracy. Three basic variables namely turbid water inflow, outflow, and water stage have been used as input variables. It was found that ANNs were able to establish valid relationship between input variables and target variable of sedimentation. The R value was 0.9806, 0.9091, and 0.8758 for training, validation, and testing phase respectively. Comparative analysis was also performed to find optimum structure of ANN for sediment deposition prediction. 3-14-1 network architecture using BR algorithm outperformed all other combinations. It was concluded that ANN possess mapping capabilities for complex, non-linear phenomenon of reservoir sedimentation.

• Journal of Korean Society of Water and Wastewater
• /
• v.20 no.1
• /
• pp.71-78
• /
• 2006

The removal of protozoa in the coagulation process was evaluated under the different pH and turbidity using the jar test after the addition of polyaluminium chloride (PAC) as a coagulant. Two well-known protozoa of Cryptosporidium parvum and Giardia lamblia were tested at the same time with turbidity, the critical water quality parameter of the water treatment process. Both protozoa were removed about 1log (and up to 2log) at the optimum injection of PAC. The source water turbidity and pH affected the removal of protozoa and turbidity. At neutral and alkaline pH, 1.3-1.7log removal of protozoa for low turbid water with 5NTU, and 1.6-2.3log removal for high turbid water with 30NTU were achieved. However, at acidic pH, maximum 0.8-1.0log and 1.1-1.2log were removed for low and high turbid water, respectively, at the optimum PAC injection of 15mg/L. The relation of protozoa and turbidity removals were expressed as the 1st order equation (significantly positive relation) in the most of the tested conditions. In addition, the relation of protozoan removals with residual turbidity were also expressed the 1st order equation (significantly negative relation), although the significance of the equations were reduced at acidic pH. Therefore, residual turbidity could be a good index of efficient protozoan removal in the coagulation process, probably except at the low pH condition.

• Korean Journal of Environmental Biology
• /
• v.24 no.2 s.62
• /
• pp.119-125
• /
• 2006

Present study aims to study antioxidant enzyme activity due to turbidity change in various tissues of Carassius auratus. As for the changes of antioxidant enzyme activity in tissues of C. auratus pursuant to the raising period under 50, 100, and 150 NTU with turbid water levels, there was no great difference between 50 NTU and 100 NTU compared to a control (0 NTU), however, it demonstrated a relatively noticeable difference at 150 NTU high turbid water level. When considering the antioxidant capacity in tissues of C. auratus in terms of DPPH free radical scavenging activity, there was shown a high activity in gill and liver tissues, therefore, it is thought that there appears a non-enzymatic antioxidant reaction when C. auratus is reared under the condition of highly turbid water. As for the enzymatic antioxidant reaction of antioxidant enzyme activity got increased as turbid water level went higher in order of 50, 100, 150 NTU, and the activities of superoxide dismutase (SOD), catalase (CAT), and glutathione-s-transperase (GST), increased in all tissues except for an integument, up to 20th day when it was started to be reared, and they showed a gradual decrease as time passed by. However, since the activity of glutathione reductase (GR) and glutathione peroxidase (GPX) is very low in almost all tissues, it is thought that the role of those enzymes would be quite ignorable in the course of antioxidant process.

• Journal of Life Science
• /
• v.18 no.12
• /
• pp.1671-1678
• /
• 2008

We investigated the effect of the turbid water on the phytoplankton community in the 4 sites of Imha reservoir. The turbidity of water was proportional to the concentrations of $SiO_2$-Si. Therefore, as the turbidity of water grow, the concentration of $SiO_2$-Si increased. And the both the turbidity of water and the concentrations of $SiO_2$-Si were increased as the water run deep. The concentration of chlorophyll-a decreased as the depth of water increased. Seventy phytoplankton taxa were identified and the most abundant group was Chlorophyceae consisting of 32 taxa (46%), and Cyanophyceae and Bacillariophyceae consisted of 12 taxa (17%). And Euglenophyceae, Synulophyceae, Cryptophyceae and Dinophyceae consisted of 6 taxa (9%), 4 taxa (6%), 3 taxa (4%) and 1 taxon (1%), respectively in Imha reservoir. The concentrations of phytoplankton were increased according to the turbidity of water because of the high amount of organic nutrition which is presented with turbid water. And especially, the concentrations of nitrogen increased easily because of the weak binding to the soil particle. In conclusion, total nitrogen and $SiO_2$-Si flowed into the Imha reservoir with soil particle, and these inorganic nutritions affect the growth of algae.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
• /
• 2010.04a
• /
• pp.383-385
• /
• 2010

This study analyzed the change of flowout and suspend solid in Andong and Imha basin according to the climate change to develop evaluation index about turbid water occurrence possibility and to support the countermeasures for turbid water management using GIS-based Soil and Water Assessment Tools (SWAT). MIROC3.2 hires model values of A1B climate change scenario that were supplied by Intergovernmental Panel on Climate Change (IPCC) were applied to future climage change data. Precipitation and temperature were corrected by applying the output value of 20th Century Climate Coupled Model (20C3M) based on past climate data during 1977 and 2006 and downscaled with Change Factor (CF) method. And future climate change scenarios were classified as three periods (2020s, 2050s, 2080s) and the change of flowout and suspended solid according to the climate change were estimated by coupling modeled value with SWAT model.

• Journal of Korean Society on Water Environment
• /
• v.28 no.2
• /
• pp.238-246
• /
• 2012

Organic matters budget in Lake Hoengseong were monthly investigated from April 2009 to November 2009. The intense rainfall occurred at between July and August and the hydrological factors were highly varied during the rainfall season. By the concentrated rainfall, the elevation, influx and efflux were sharply increased and the turbid water was also flowed into the middle water column in Lake. The inflow of turbid water increased the nutrient concentrations in water body and this appears to stimulate of phytoplankton regard as the primary productivity of influx of organic matter. Monthly average concentration of dissolved organic carbon (DOC) was generally higher than the particulate organic carbon (POC) concentration in Lake, but Temporal and spatial variation of POC concentration was higher than DOC and the maximum POC concentration was recorded in surface water in August, had the highest phytoplankton biomass. Organic carbon concentration in inflow site was rarely changed during the dry season, but the concentration was rapidly increased by the initial intense rainfall. In organic matters budget, the most of the organic matters was inflowed from the inflow site at rainfall season. Especially, the influx of allochthonous organic matters during the intense rainfall was 72.4% in the total influx organic matters.

• Journal of the Korean Society of Food Culture
• /
• v.22 no.3
• /
• pp.359-364
• /
• 2007

Effects of Takju(Korean turbid rice wine) lees on noodle investigated by substituting Takju lees water extract powder for each 2% and 4% wheat flour in sample II and III, respectively. The lightness(L) of uncooked noodles was decreased, whereas that of cooked noodles was increased with increasing amount of extract added. Redness(a) and difference of total color(${\Delta}$E) were significantly increased according to the amount of extract added in uncooked and cooked noodles. Yellowness(b) of the noodles containing 2% Takju lees water extract powder was exhibited lowest values in uncooked and cooked noodles. In cooking property of noodles, turbidity of soup decreased in proportion to amount of extract added, 2% and 4% in sample II and III, respectively whereas the weight and volume of noodles were not significant than those of control. Tension of cooked noodle was highest in sample II and lowest in sample III. Texture profile analysis of cooked noodle showed an significant increase of hardness in addition of Takju lees water extract powder but not significant different in springiness, chewiness, adhesiveness. Cohesiveness was significantly lowest in sample II. The sensory evaluation showed that significant difference between noodles with 2% addition groups and control was not recognized but was recognized 4%. Therefore, based on cooking properties and sensory evaluation, Takiu lees water extract powder up to 4% could be substituted for wheat flour.