• Journal of the Korean association of regional geographers
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• v.20 no.2
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• pp.176-188
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• 2014

Since the late 1990s, a nationwide movement against dam and river-mouth weir plans in Japan has been promoted with a movement against a river-mouth weir for the Nagara river(長良川). This movement has been a catalyst for institutional frameworks on the central government's dam and river-mouth weir plans. Subsequently, water resource and river management policies have entered a new phase, with provinces governors's participation in "Statements on withdrawal from dam and river-mouth weir" as well as the seizing of power by the Democratic Party. However, problems with dams and river-mouth weirs have been confused due to poor countermeasures from the Democratic Party and to the Liberal Democratic Party(LDP)'s return to power. The fundamental causes on this situation are the non-establishment of fiscal norms for public projects and the rigidity of the water-right allocation system in Jananese policy-making processes. To successfully settle future policy on water resources and rivers, the first priority is to prepare specific institutional frameworks on finance of public projects and to organize a practical policy coordination system among government organizations. These policy tasks provide implications for river and water management policy in Korea.

• Journal of Korean Society of Forest Science
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• v.101 no.1
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• pp.113-120
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• 2012

The purpose of this study was to find out the effect of a torrent control structure using customized tetrapods on the forest water quality, fishes, snials and streamwater ecology conservation and management. The study was conducted in the Honggye valley located in Sanchung-gun, Gyungsangnam-do, and stream water quality and streamwater ecology was compared before and during 2 years after construction of torrent control structure. After construction of the torrent control structure using customized tetrapods, pH of stream water didn't get out of the range of River water quality standard class I. After 2 years construction of the torrent control structure using customized tetrapods, Dissolved Oxygen concentration didn't change, and Electrical Conductivity measurements agreed well within the range of normal clean stream water quality. After construction of the torrent control structure using customized tetrapods, fishes and snials up and down stream movement didn't influence of the tetrapods dam. Stream water quality during 2 years after construction of the torrent control structure was similar to before construction. Therefore, it was find out that the torrent control structure didn't affect stream water quality and ecology.

• Journal of Gifted/Talented Education
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• v.22 no.4
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• pp.855-874
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• 2012

This research aimed to obtain basic data for elementary school students to form proper concepts by comparing the science gifted students and the ordinary students of elementary school with regard to the groundwater concept, formation process, existence forms, and movement. The research subjects were 65 fifth and sixth graders of the elementary school students and the spatial ability test was conducted on the subjects, and 4 science gifted students and 8 ordinary students chosen from the subjects were analyzed using half-structured interview data and ground water drawing drawn by the students. The conclusion derived in accordance with the research purpose is summarized as follows. It was found that there were no great differences in the answers to the question asking what groundwater is between the science gifted elementary school students with high spatial ability and the ordinary elementary school students with moderate spatial ability. The ordinary students with low spatial ability tended to regard groundwater as the concept of water and sewage. In the concept of the formation process of groundwater, the science gifted elementary school students with high spatial ability explained it by citing diverse surface water such as rainfall, river water, lake, and waterfall, and the ordinary elementary school students with moderate spatial ability all mentioned only rainfall and river water and could not explain diverse spatial factors. The ordinary elementary school students with low spatial ability mentioned rainfall and river water and perceived that groundwater was formed artificially. In the concept regarding the existence form of groundwater, the ordinary elementary school students with low spatial ability could not think of space perception that small pore space exists in earth or soil in the ground. The science gifted elementary school students with high spatial ability knew that groundwater exists in pore space with regarding groundwater movement, the ordinary elementary school students with low spatial ability thought that there was no groundwater movement and that it could be moved only by artificial facilities. There were differences in the perception of pore space and in the perception of existence and non-existence of groundwater movement accordingly, but for most of the elementary school students, the concept of groundwater was formed differently from the scientific concept. It is considered that most of the elementary school students formed erroneous concept about groundwater and could not connect ground water under the surface of the earth with the substances forming its surroundings with regard to the concept of groundwater.

• Membrane and Water Treatment
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• v.11 no.3
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• pp.201-206
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• 2020

Electrodialysis (ED) is used in wastewater treatment, during the processing and recovery of beneficial materials, to produce usable water. In this study, sulfate and chlorine ions, which are the anions majorly used for electroplating, were studied as factors affecting the recovery of copper, nickel and water from wastewater by electrodialysis. Although the removal rates of copper and nickel ions were slightly higher with the use of chlorine ions than of sulfate ions, the removal efficiencies were above 99.9% under all experimental conditions. The metal ions of the plating wastewater flowed through the ion exchange membrane of the diluate tank and the concentrate tank while all the water moved together due to electro-osmosis. The migration of water from the diluate tank to the concentrate tank was higher in the presence of a monovalent chloride ion compared to that of a divalent sulfate ion. When sulfate was the anion used, the recoveries of copper and nickel increased by about 25% and 30%, respectively, as compared to the chloride ion. Therefore, when divalent ions such as sulfate are present in the electrodialysis, it is possible to reduce the movement amount of water and highly concentrate the copper and nickel in the plating wastewater.

• Ocean and Polar Research
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• v.34 no.2
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• pp.219-228
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• 2012

Tintinnid species distribution has been monitored in the northern East China Sea (ECS) in the summer of 2006 through 2011. This is used to understand the water mass movements in the northern ECS. The warm oceanic tintinnid species had largely spread in 2007 in the area, indicating that there was greater warm water extension into the northern ECS. However the extension of neritic water within the Changjiang diluted water mass has strengthened in 2008 and 2010 because the neritic species distribution had relatively grown in both years. These annual results based on the biological indicators of tintinnid species are well matched with the salinity change in the area. The warm oceanic species, Dadayiella ganymedes had frequently occurred over the study years and had shown a significant relationship with the salinity change. This is valuable as a key stone species for monitoring the intrusion of the Kuroshio within the northern ECS. Information from tintinnid biological indicators can support physical oceanography data to confirm ambiguous water mass properties.

• THE JOURNAL OF KOREAN ORIENTAL ONCOLOGY
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• v.1 no.1
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• pp.213-230
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• 1995

The present work was done to investigate the pharmacological effectiveness of Guichoolpajing-Tang and Gamiguichoolpajing-Tang. The extracted water of those two prescription were administered to experimintal animals and determined analgesic, anti-pyretic, anti-inflammatory effects and effects on intravascular coagulation, spontaneous morements of the isolated rat uterus, the uterine contracion induced by oxytocin or $PGF_{20}$, lifespan of mice implanted intraperitoneally with Sarcoma 180. The following results were obtained. 1) The extracted water of Guichoolpajing-Tang and Gamiguichoolpajing-Tang were revealed significant analgesic effect. 2) The extracted water of Guichoolpajing-Tang and Gamiguichoolpajing-Tang showed anti-pyretic effect. 3) The extracted water of Guichoolpajing-tang and Gamiguichoolpajing-Tang showed anti-inflammatory effect. Especially, the extracted water of Gamiguichoolpajing-Tang showed more significant dffect than another. 4) Concerning the degree of concentration of FDP, Gamiguichoolpajing-Tang treated groups tevealed significant decreases. 5) The extracted water of both prescriptions revealed uterus relaxation on the spontaneous movement of the isolated rat uterus and showed uterine contraction induced by oxytocin or $PDF_{2}$. Especially Guichoolpajing-Tang showed more significant effect than another. 6) The extracted water of both prescription both prescriptions showed effect on lifespan of mice implanted intraperitoneally with Sarcoma 180.

• Magazine of the Korean Society of Agricultural Engineers
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• v.9 no.2
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• pp.1296-1300
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• 1967

This study was made through the utilization of heavy soil taken from the experimental plot of heavy soil in Konkuk University, Changan-dong, Sungdong-ku, Seoul. The soil used in the experiment has the following physical characteristics: 1. The soil is very compact, impervious, and unfit for any plant growth, 2. For improvement of the soil, tile drainage practice has been employed, 3. According to the general theory of tile drainage, it is unnatural that the effect of drainage is actually observed in such a soil. The followings are the results of the experiment: 1. Water moved to crosswise when the plotted soil profile was not broke. In this case the upper sloped part was dry while the bottom part was moistned. The upper part of the tile was also moistned. 2. The crosswise movement of water was not observed in the artificially broken plot of subsoil. However, the water flow from the tile was observed for long period as a result of the increase of soil void, seepage, aeration, and water holding capacity. However, the water flow from the tile in the plot of unbroken subsoil was observed only in short period and soon the flow was stopped. 3. the distance between the tile laid in the heavy soil should not exceed 10m for the efficient drainage. 4. When the pF is 2.5 in the subsoil the moisture content was between 23.97% and 28.20%. However, when the water saturated in the subsoil the moisture content was between 34.30% and 22.10%. Accordingly without the higher pF than 2.5 the water can not be absorbed and therefore the drainage can not be occured.

• Journal of Korean Society of Water and Wastewater
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• v.30 no.1
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• pp.9-17
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• 2016

Disinfectant/oxidation process is a crucial process in water treatment for supplying safe drinking water. Chlorination is still widely used for water treatment area due to its effectiveness on microbial inactivation and economic feasibility. Recently, disinfection concern in marine environment is increasing, for example, movement of hazardous marine organism due to ballast water, marine environmental degradation due to power plant cooling water discharge, and increase of the amount of disinfectant in the offshore plant. It is needed to conduct the assessment of disinfectant behavior and the development of disinfectant prediction model in seawater. The appropriate prediction model for disinfectant behavior is not yet provided. The objective of the study is to develop chlorine decay model in seawater. Various model types were applied to develop the seawater chlorine decay model, such as first order decay model, EPA model, and two-phase model. The model simulation indicated that chlorine decay in seawater is influenced by both organic and inorganic matter in seawater. While inorganic matter has a negative correlation with the chlorine decay, organic matter has a positive correlation with the chlorine decay.

• Journal of the Society of Naval Architects of Korea
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• v.45 no.4
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• pp.345-352
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• 2008

The motion of a projectile initiated by the release of highly pressurized air is simulated presuming the flow field as a two dimensional one. The effects of water compressibility on projectile movements are investigated, comparing results based on the Fluent VOF model where water is treated as an incompressible medium with those from the presently developed VOF scheme. The present model considers compressibility of both air and water. The Fluent results show that the body moves farther and at higher speeds than the present ones. As time proceeds, the relative difference of speed and displacement between the two results drops substantially, after acoustic waves in water traverse and return the full length of the tube several times. To estimate instantaneous accelerations, however, requires implementation of the water compressibility effect as discrepancies between them do not decrease even after several pressure wave cycles.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.59 no.4
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• pp.411-416
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• 2010

Interest in application of ultraviolet light technology for primary disinfection of potable water in drinking water treatment plants has increased significantly in recent years. The efficacy of disinfection processes in water purification systems is governed by several key factors, including reactor hydraulics, disinfectant chemistry, and microbial inactivation kinetics. The objective of this work was to develop a computational fluid dynamics(CFD) model to predict velocity fields, mass transport, chlorine decay, and microbial inactivation in a continuous flow reactor. In this paper, It describe the how to design optimal UV disinfection device for ground water, BWT and rainwater. Spring shape instrument silver coated located in inner side of disinfection chamber. It make lead the active flowing movement target water and maximize disinfection performance. To search the optimal design method, it was performed computer simulation with 3D-CFD discrete ordinates model and manufactured prototype. Using proposed design method, performed simulation and proved satisfied performance.