• 제목/요약/키워드: In-Water

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필리핀의 수자원 평가 (Water Resources Evaluation in the Philippines)

  • ;이주헌;정상만
    • 한국습지학회지
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    • 제10권3호
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    • pp.47-56
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    • 2008
  • This paper sought to provide information regarding the water resources in the Philippines, focusing on the issues of water quality, status of water use and water scarcity, and other threats to water availability. Although the country has sufficient amount of water resources, it was found out that water availability is still threatened by some major water resources problems: increasing water demand due to drastic growth in population, water resources pollution, droughts and flooding and weak institutional framework to address these problems. Water quality problems include increasing groundwater and surface water pollution. Moreover, drought and flooding have also increased damages in recent years due to deteriorating watersheds and high economic and population growth. In relation to these, the government enacted national laws to define and deal with water control and quality management. The objective of this research was to present and evaluate current conditions and issues on Philippine water resources.

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급수관로계에 설치된 수격흡수기의 수격흡수효과에 관한 실험적 연구 (Experimental Study on the Water Hammer Absorption Effects of Water Hammer Arrester in the Water Supply Piping System)

  • 최중근;이석종;이명호;성재용
    • Journal of Advanced Marine Engineering and Technology
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    • 제30권3호
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    • pp.396-402
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    • 2006
  • In this study, dynamic characteristics of water hammer pressure in water supply piping system with water hammer arrester has been investigated experimentally to characterize the transient pressure of water hammer in high rise building. Experiments were conducted to verify the absorption effects by water hammer arresters with 3 different gas volumes of water hammer pressure generated by sudden valve closure. As the results, it has been found that zoning and sizing of pipe diameter for suitable flow velocity and water hammer arresters with effective pressure absorption capacity have to be installed to protect water hammer problems in building water supply piping system.

음용수질 기준과 관리방안 (Recent Development of Drinking Water Quality Standard and its Application)

  • 권숙표
    • 환경위생공학
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    • 제7권2호
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    • pp.83-94
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    • 1992
  • Recently water demand is increasing as the industry prospers. The increase of water demand is followed by the increase of wastewater discharge which pollutes rivers and ground water extensively. These rivers, reservoirs and ground water are sources for drinking water and their contamination affects the quality of water supply and other potable water. In Korea there are 776 water treatment plants which supply drinking water from main rivers or reservoirs. Rivers are the biggest water source for drinking water is being contaminated, the innovation of treatment process is needed. The construction and operation of water supply facilities is under the control of the Ministry of Construction and the water supply offices of cities and provinces. However, drinking water quality is under the control of the bureau of sanitation in the Ministry of Health and Social Affairs. There are 33 items in drinking water quality standards of Korea. Trihalomethanes, Selenium, Diazinone and other three of pesticides have been included lately, The Ministry of Health and Social Affairs is planning to enhance. the level of $VOC_S$(Vola-tile Organic Compounds) standard. Drinking water quality standard is the goal to protect the quality of supply water and ground water. In order to protect the source water from domestic or industrial water, technological improvement and adequate investment should be urgently made. The ultimate goal of drinking water quality is safety and health of consumers. The more stringent the standard are, the better the water quality will be. As the drinking water quality standards become more stringent this year, various and positive solutions by the authorities concerned must be prepared.

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Water Masses and Salinity in the Eastern Yellow Sea from Winter to Spring

  • Park, Moon-Jin;Oh, Hee-Jin
    • Ocean and Polar Research
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    • 제26권1호
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    • pp.65-75
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    • 2004
  • In order to understand the water masses and their distribution in the eastern Yellow Sea from winter to spring, a cluster analysis was applied to the temperature and salinity data of Korea Oceanographic Data Center from 1970 to 1990. From December to April, Yellow Sea Cold Water (YSCW) dominates the eastern Yellow Sea, whereas Eastern Yellow Sea Mixed Water (MW) and Yellow Sea Warm Water (YSWW) are found in the southern part of the eastern Yellow Sea. MW appears at the frontal region around $34^{\circ}N$ between YSCW in the north and YSWW in the south. On the other hand, Tshushima Warm Water (TWW) is found around Jeju Island and the South Sea of Korea. These water masses are relatively well-mixed throughout the water column due to the winter monsoon. However, the water column begins to be stratified in spring due to increased solar heating, the diminishing winds and fresh water discharge, and the water masses in June may be separated into surface, intermediate and bottom layers of the water column. YSWW advances northwestward from December to February and retreats southeastward from February to April. This suggests a periodic movement of water masses in the southern part of the eastern Yellow Sea from winter to spring. YSWW may continue to move eastward with the prevailing eastward current to the South Sea from April to June. Also, the front relaxes in June, but the mixed water advances to the north, increasing salinity. The salinity is also higher in the nearshore region than offshore. This indicates an influx of oceanic water to the north in the nearshore region of the eastern Yellow Sea in spring in the form of mixed water.

한국형 상향식 농업용수 거버넌스 모형 개발 (Development of a Bottom-up Agricultural Water Governance Model in Korea)

  • 이슬기;최경숙
    • 농촌계획
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    • 제28권3호
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    • pp.49-59
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    • 2022
  • Recently, Korea aimed to increase water use efficiency by implementing integrated management according to the water management unification policy. Considering the enormous use of water resources in the agricultural sector, it is necessary to efficiently conserve water in terms of demand management by intensifying the stakeholders' involvement and awareness campaigns. The existing agricultural water management system in Korea is based on a top-down approach by which the government agencies directly plan budgets and policies to be enforced on and implemented by farmers, with little to no involvement of farmers in the decision-making process. However, this process has hindered the desired water resources management and the water conservation goal at the field level. Moreover, the limited research on water governance operations focusing on agricultural water creates a knowledge gap, particularly in Korea. Thus, it is necessary to investigate water governance cases with successful implementations in agricultural and rural areas to identify the factors applicable to domestic governance in Korea. In addition, a more systematic governance model should be established by identifying the subjectivity of the stakeholders' involvement in agricultural water governance. Therefore, this study proposed a new bottom-up model for agricultural water governance, which aims to raise the problem of autonomous water governance while promoting stakeholders' voluntary participation in agricultural water management and reflecting farmers' involvement in the decision-making process. Moreover, if agricultural water governance is expanded nationwide by reflecting agricultural and water resource policies in the future, it is believed that positive effects can be achieved in increasing utilization efficiency and securing sustantiality through agricultural water saving.

이상적인 음료수 공급을 위한 수질관리에 관한 연구 (Study on the Water Management to get High Quality of Drinking Water)

  • 김형석;신현덕;박경석
    • 환경위생공학
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    • 제6권1호
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    • pp.7-25
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    • 1991
  • Until now, pure drinking water grnerally menas the water without taste, odor, general bacteria, coliform, and other exotic substance. Such a definition has been changing recently due to the finding of numerous other inorganic and organic substances unknown to us. 10 years ago, major causes of death were infectious agents and parasites contained in water, but recently, it has become apparent that some substances contained in drinking water cause cancer and heart diseases. We must drink about 2L of water everyday in order to maintain healthy condition. Waters used for drinking include tap water, well water, spring water, filtered water, etc., but the quality of drinking water has more polluted due to the industrial development and population increase. For example, industrial waste waters from industrial plants pollute the water supply sources ; toxic substances contained in the waste waters pollute the ground water sources by penetrating the geological strata, and municipal, livestock, public building waste waters also pollute the water supply sources. Sometimes, the polluted surface waters were announced to be polluted by various kinds of orgainc substance, and it is reported that the pollution of ground water by orga nic substances has few in number but high in its concectration comparing with those of surface water. As the water quality pollution level increases, so the amount of disinfectant also increase. For example, chlorine solution, one of widely used disinfectants, creates trihalomethane(THM), a carcinogen, and halogen compounds. According to Oliver, through chlorine disinfection process, humine substance and chlorine create bolatile organic halide and nonvolatile organic halide by chemical reaction. There are tens or hundreds filtering devices, but filtering principles and maintenance metjhods are different, so their efficiency tests are needed. According to Smith, the effeciency tests aginst over 30 Ameican filtering devices show that 10 devices can remove 85% of volatile organics and further studies on filtered waters are underway. In consideration of important impacts of polluted drinking water on national health, authors studied the state of water quality pollution against tap water used as drinking water, filtration device passed water, ground water, and conserved drinking water ; tested the efficiency of filtration devices for tap water ; tried to sep up the detection method by using ion chromatography based on negative ion and positive ion by using single column, and attemped the simple filtration method for general households.

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학교 급수위생에 관한 연구 (A Survey of Sanitation of the Water Supply System in Schools)

  • 권은미
    • 한국환경교육학회지:환경교육
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    • 제3권1호
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    • pp.125-129
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    • 1992
  • The purpose of this study was to investigate the condition of school water supply systems and to provide a way to supply safe and sanitary water in schools. In 1991 present, 56.9% of schools in the whole nation are provided with water supply system. And in urban schools, the percentage of small water supply system was larger than that in city. In the survey on water quality of supply water in Seoul city, the items violating the water quality standard were total bacteria, Zinc and Manganse. For supply the safe drinking water changing the old water mains and executing periodical water quality surveys are needed in addition regulations on school supply water and sanitation are also necessary to the drinking water management in schools.

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제주특별자치도 물인프라 현황 및 개선방향 (Current status of Jeju special self-governing province's water infrastructure and direction for improvement)

  • 김진근
    • 상하수도학회지
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    • 제35권6호
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    • pp.497-505
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    • 2021
  • This paper investigates the current status of Jeju special self-governing province (JSSGP)'s water infrastructure and recommends directions for improvement. JSSGP relies on groundwater for most of its water resources. Recently, water usage has been steadily increasing due to the increase of residents and tourists while the quality of groundwater has been steadily worsening. Deterioration in water quality of groundwater can be seen through the increase in concentration of nitrate nitrogen and microorganisms. To overcome such problems, water consumption must be reduced by water demand management in all fields including residential and agricultural water use. The quality of water resources should be preserved through the management of pollutants. For efficient management of water resources, great efforts should be made to reduce the leakage rates in household and agricultural water, which is currently at the highest level in the country. Furthermore, diversification of water intake sources other than groundwater is needed, especially for agricultural water supply. For water and sewerage facilities, compliance with drinking water quality standards and discharge water quality standards must be achieved through the optimization of operation management. This process requires recruiting professionals, improving existing workers' expertise, and improving facilities.

수질오염총량관리 단위유역 수질변화 유형분석 - 낙동강수계를 대상으로 - (A Study on the Water Quality Patterns of Unit Watersheds for the Management of TMDLs - in Nakdong River Basin -)

  • 박준대;김진이;류덕희;정동일
    • 한국물환경학회지
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    • 제26권2호
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    • pp.279-288
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    • 2010
  • The water quality variations or changes are closely relevant to the characteristics of unit watersheds and have an effect on the attainment of their water quality goal. This study was conducted to analyze the water quality distribution and its change patterns of unit watersheds in Nakdong river basin. It revealed that 25 unit watersheds out of 41 showed the normality in water quality. Most of unit watersheds had a considerable variation in water quality, especially in the season of spring and summer but a little in terms of flow rate. Annual relative differences in water quality ranged from 13.0 to 26.6% with the maximum of 75%. 28 unit watersheds (62%) had the tendency to decrease in water quality as the flow rate increased while 13 (38%) to increase. The extension of standard flow led to considerable differences in water quality depending on its ranges, which meant uncertainties might be included in the process of TMDL development. It is suggested that annual average flow rate should be chosen as a standard flow in the area where the water quality change has little relation to the flow rate.

지하수에 대한 소고 (A Note on Under ground water)

  • 최귀열
    • 한국농공학회지
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    • 제8권1호
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    • pp.1055-1063
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    • 1966
  • Ground water hydrology may be defined as the science of the occnrrence, distribution, and movement of water below the surface of the earth. Geohydrology has an identical connotation, and hydrogeology differs only by its greater emphasis on geology. Ground water referred to with out further specification is commonly understood to mean water occupying all the voids with in a geologic stratum. This saturated zone is tobe distinguished from an unsaturated, or aeration zone where voids are filled \yith water and air. Water contained in saturate:! zones is important for engineering works, geologic studies, and water supply developements Conseqently, the occurrence of water in these zones will be emphasized here. Un-saturated zones are usualiy found above saturated zones and extending upward to the ground surface. Because this water includes soil moisture with in the root zone, it is a major concern of agricultlre, botmy and soil science. No rigid demarcation of waters, between the two zones is possible, for they possess an iriterdependent boundary and water can move from zone to zone in either science, including eology, hydrology, meteorology, and oceanography are concerned with earths water, but ground water hydrology may be regarded as a specialized science combining elements of geology, hydrology, and fluid mechanics. Geology governs the occurrence and distribution of ground water, hydrology determines the supply of water to the ground, and fluid mechanics explains its movement. To provide maximum development of grofnd water resources. for benefical use requires thinking in terms of an entire ground water basin. In order to inorease the natural supply of ground water, man has attempted to artifially recharge ground water basins. Coastal aquifers come in contact with the ocean at seawater of the coastline. Fresh ground water is discharged in to the ocean. the seaward flow of ground water has been decreased or even reversed, Sea water penettating in land in aquifer.

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