• Korean Journal of Ecology and Environment
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• v.33 no.3 s.91
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• pp.213-221
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• 2000

Seasonal oxygen content and deficit rates were evaluated from 17 sites of Taechung Reservoir during 1993${\sim}$1994. In 1993, river inflows peaked during the monsoon in July${\sim}$August and disrupted thermal stratification and anoxic layers in the headwaters, thereby confining the anoxia to the mid-lake and downlake reach. The volume of anoxic water with < 4 mg/l DO comprised only < 10% of the total lake volume in this period. In contrast, during monsoon 1994, 85% of total lake volume was subject to hypoxic conditions with oxygen concentrations < 30% saturation, resulting in massive fishkills (Hypomesus olidus). Relative areal oxygen deficit (RAOD) was -0.024mg O$_{2}$cm$^{-2}$d$^{-1}$ during monsoon 1993, whereas it rapidly decreased at the rate of 0.080mg O$_{2}$cm$^{-2}$d$^{-1}$ during monsoon 1994. Anoxic factor (AF) showed a same interannual pattern as the RAOD and was greater >50 d in 1994 (76.5 d) than 1993 (21.3 d). Thus, the reservoir showed a river-characteristics (6${\sim}$11 mg/l DO) in 1993 while lacustrine conditions (<4mg/l DO) dominated in 1994. Regression analysis showed that the variation of summer DO was mostly determined (R$^{2}$=0.99, p<0.0001) by inflow. These findings suggest that the primary factor regulating the oxygen content in this system during summer is an intensity of the monsoon rain.

• Journal of Korea Water Resources Association
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• v.54 no.6
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• pp.443-452
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• 2021

The authors obtained the discrete hedging rule for a reservoir's water supply operation by applying mixed-integer programming to save more water by earlier rationing of water supply for a drought period. The 'water supply adjustment guide' is the current operational method applied to the multipurpose reservoirs, and it was derived by a simulation method. Applying the two rules to the Hapcheon multipurpose dam's reservoir simulations with the inflow record from 2003 to 2018, the water supply deficit occurred for the long drought from 2015 to 2018. Especially, the no water supply or intermittent water supply persisted for the second half of 2017. The water supply adjustment guide had the 'normal water supply recovery threshold on storage,' which resulted in the water supply being unavailable in July 2017; then, the water supply suspension occurred until January 2018, when the reservoir storage was greater than the normal water supply recovery threshold. Despite the storage increasing due to the inflow of water into the reservoir, the suspension occurrence needs to be improved in practice. The current water supply adjustment guide and the discrete hedging rule for a reservoir's water supply operation are useful and realistic as the reservoir operation guide, which shows the concept of reducing water supply during the drought phase as scientific figures. However, to improve the reservoir simulation results, which do not provide any or intermittent water for several months, it is necessary to increase the current water supply reduction for drought phases.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.30 no.4
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• pp.347-351
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• 1985

The effect of leaf water content on apparent photosynthesis and respiration of tobacco plants(five varieties) was studied under the condition without the irrigation for 10 days after the plants were sufficiently watered on the first day. The wild race (N. longiflora) among varieties showed highest apparent photosynthesis (AP) and AP had a positive correlation with specific leaf weight. N. longiflora and Andongyeob were different in their AP from the other varieties significantly under the water stress condition. Respiration rate also decreased to be simillar to AP except slight increase at early stage of water deficit. The stomatal resistance and the mesophyll resistance increased in the stressed plants. The water stress resistant character seems to be mainly due to open stomata.

• International journal of advanced smart convergence
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• v.9 no.3
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• pp.1-8
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• 2020

Water consumption has grown at more than 2.5 times, comparing the past century. About 2.8 billion people live in river basins with some form of water deficit, because more than 75 % of the river flows are withdrawn for agriculture and other needs. Challenges faced by more and more countries in their struggle for economic and social development are increasingly related to water. This paper proposes a test of an effective local river field environment management solution. And describing a part of a pilot project for the ministry of water resources of Uzbekistan. Current work focused on direct action items of the existing project and describe an IoT routing based solution for local river field environment management solutions. Suggested technological decisions provided by needs and on-site testing results. The paper describes the backbone of IoT routing based river water resources management system.

• Journal of Physiology & Pathology in Korean Medicine
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• v.18 no.3
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• pp.797-807
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• 2004

This research investigates the effect of the Hibiscus syriacus(HSS) on Alzheimer's disease. The effects of the HSS extract on the behavior in the Morris water maze experiment; the expression of IL-1β, TNF-α, IL-1β mRNA, TNF-α mRNA, CD68/GFAP and RDS; the the infarction area of the hippocampus, and brain tissue injury in Alzheimer's diseased mice induced with M were investigated. The HSS extract group showed a significant inhibitory effect on the memory deficit on the mice with Alzheimer's disease induced by βA in the Morris water maze experiment. The HSS extract group suppressed the over-expression of IL-1β, TNF-α, IL-1β and TNF-α mRNA, CD68/GFAP, RDS in the mice with Alzheimer's disease induced by βA. The HSS extract reduced the infarction area of hippocampus, and controlled the injury of brain tissue in the mice with Alzheimer's disease induced by βA. This study suggest that HSS may be effective for the prevention and treatment of Alzheimer's disease

• Water for future
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• v.18 no.4
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• pp.317-325
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• 1985

In the analysis, monthly streamflow records atthe gauging station in Nakdong, Han and Geum river were used. Also, the fitness of monthly streamflow to Gamma and Long-normal distribution was tested by Kolomogorv-Smirnov test. The results obtained in this study can be summarized as follws (1) The fitness of monthly streamflow to two-parameter Gamma distribution was tested by Kolomorov-Smirnov test, which fits well to this Gamma distribution (2) The Run-length and Run-sum were simulated by the Gamma model. In this result, run-length and Run-sum of monthly streamflow were fit for Gamma model (3) The mean decreases (increases) the expected surplus (deficit) Run-Sum of the monthly streamflow. The higher the truncation level of negative Run-length and Run-sum the larger is the effect of mean.

• Journal of Physiology & Pathology in Korean Medicine
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• v.18 no.6
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• pp.1795-1804
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• 2004

This research investigated the effect of the Chaenomelis fructus(CMF) on Alzheimer's disease. The effects of the CMF extract on the behavior in the Morris water maze experiment; the expression of IL-1β, TNF-α, ROS on the microglial cell; IL-1β mRNA, TNF-α mRNA, CD68/GFAP and MDA on the brain tissue; the infarction area of the hippocampus, and brain tissue injury in the mice with Alzheimer's disease induced by βA were investigated. The CMF extract group showed a significant inhibitory effect on the memory deficit on the mice with Alzheimer's disease induced by βA in the Morris water maze experiment. The CMF extract group suppressed the over-expression of IL-1β, TNF-α, IL-1β and TNF-α mRNA, ROS, MDA, CD68/GFAP in the mice with Alzheimer's disease induced by βA. The CMF extract reduced the infarction area of hippocampus, and controlled the injury of brain tissue in the mice with Alzheimer's disease induced by [3A. This study suggest that CMF may be effective for the prevention and treatment of Alzheimer's disease.

• Journal of Korea Water Resources Association
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• v.32 no.5
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• pp.515-524
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• 1999

A methodology to resolve a TOPMODEL problem has been suggested, which is associated with the spatial distribution of soil moisture behaviour in a runoff mechanism. A procedure to integrate the spatial information of saturation deficit in the TOPMODEL reflects the connectivity of saturated area in a watershed. The developed algorithm includes an improved basis in tracing the runoff path without increasing the number of parameters. The performance of the developed algorithm has been tested to an upland subwatershed, namely Dongok, which is the IHP watershed located at Wichon, Korea. Comparing with the original statistical version of the TOPMODEL, it has been found that the suggested algorithm can relax an overestimation of peak rate in the runoff simulation.

• BMB Reports
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• v.41 no.4
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• pp.338-343
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• 2008

Dehydrins (DHNs) compose a family of intrinsically unstructured proteins that have high water solubility and accumulate during late seed development at low temperature or in water-deficit conditions. They are believed to play a protective role in freezing and drought-tolerance in plants. A full-length cDNA encoding DHN (designated as ClDhn) was isolated from an oriental medicinal plant Codonopsis lanceolata, which has been used widely in Asia for its anticancer and anti-inflammatory properties. The full-length cDNA of ClDhn was 813 bp and contained a 477 bp open reading frame (ORF) encoding a polypeptide of 159 amino acids. Deduced ClDhn protein had high similarities with other plant DHNs. RT-PCR analysis showed that different abiotic stresses such as salt, wounding, chilling and light, triggered a significant induction of ClDhn at different time points within 4-48 hrs post-treatment. This study revealed that ClDhn assisted C. lanceolata in becoming resistant to dehydration.

• Journal of Physiology & Pathology in Korean Medicine
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• v.20 no.2
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• pp.471-476
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• 2006

Chongmyung-tang(CMT, 聰明湯), oriental herbal medicine which consists of Polygaglae Radix(遠志), Acori Graminei Rhizoma(石菖蒲) and Hoelen(白茯神) has effect on amnesia, dementia. In order to evaluate effect of CMT on memory and learning in mice, CMT extract was used for studies. This paper describes the effects of CMT extract on memory and learning processes by using the passive and active avoidance performance tests, novel object recognition task and water maze task. The CMT extract ameliorated the memory retrieval deficit induced by ethanol in the passive avoidance responses but did not affect ambulatory activity of normal mice. These results suggest that CMT has an ameliorating effect on memory retrieval impairment. CMT extract decreased spontaneous motor activity(SMA) in the latter sessions of memory registration in active avoidance responses. These results suggest that CMT has partly transquilizing or antianxiety effects. In novel object recognition task to measure visual recognition memory, CMT-administered mice enhanced in long term memory for 1-3 days. In water maze task to measure spatial learning, which requires the activation of NMDA receptors in the hippocampus, spatial learning in CMT-administered mice was faster than in wild-type mice. These results suggest that CMT enhances memory and activates NMDA receptors.