• Title/Summary/Keyword: "On-water"

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SOUTH KOREA′S WATER RESOURCES POLICY TOWARD THE 21ST CENTURY: CONFLICTING VIEWS

  • Choi, Yearn-Hong
    • Water Engineering Research
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    • v.2 no.2
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    • pp.103-112
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    • 2001
  • Issues and problems in formulating South Korea's water resources policy are discussed in terms of water quantity and quality. South Korean needs both water conservation and water supply capability for the growing population and economic activities. The government has attempted to build more large-scale dams to store and supply water for residential, farming and industrial uses, but the environmentalists who emphasize conservation and environmental protection oppose the government. The environmentalists are popular among the general public. Water quality has been deteriorating from point- ad non-point sources. urban and farm runoffs are serious pollutants. All want by preserve water quality. There is no dispute on this matter between the government and the environmentalists. Money is hard to come by to preserve water quality. Economic and financial crises and no self-sufficient local governments' revenue structure are pessimistic. Basic survey on water resources, hydrology and hydraulic is badly needed for the future water resources planning.

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Water Resources Evaluation in the Philippines (필리핀의 수자원 평가)

  • Rubio, Christabel Jane;Lee, Joo Heon;Jeong, Sang Man
    • Journal of Wetlands Research
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    • v.10 no.3
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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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An experimental study on decision making for multi-source water (다중수원 수처리 의사결정에 관한 실험적 연구)

  • Jung, Jungwoo;Cho, Hyeong-Rak;Lee, Sangho;Chae, Soo-Kwon
    • Journal of Korean Society of Water and Wastewater
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    • v.29 no.1
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    • pp.1-9
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    • 2015
  • A combined treatment system using multiple source water is becoming important as an alternative to conventional water supply for small-scale water systems. In this research, combined water treatment systems were investigated for simultaneous use of multi-source water including rainwater, ground water, river water, and reclaimed wastewater. A laboratory-scale system was developed to systematically compare various combinations of water treatment processes, including sand filtration, microfiltration (MF), granular activated carbon (GAC), and nanofiltration (NF). Results showed that the efficiency of combined water treatment systems was affected by the quality of feed waters. In addition, a simply approach based on the concept of linear combination was suggested to support a decision-making for the optimum water treatment systems with the consideration of final water quality.

A study on Water Quality Changes in Distribution System (Factor analysis of deterioration of water quality & Modelling of free chlorine) (상수도 배관망에서의 수질변화에 관한 연구 (수질악화의 영향인자 분석과 잔류염소 모델링))

  • Lee, Hyun Dong;Chung, Won Sik;Moon, Sook Mi
    • Journal of Korean Society of Water and Wastewater
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    • v.11 no.3
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    • pp.59-66
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    • 1997
  • Although it produces well-treated water in water treatment plant, water quality at the tap can be changed depending on the state of pipes. It is because water quality deteriorates as plant water passes through pipeline networks. Therefore, the improvement of not only water treatment technology but also O & M of water pipelines is required to supply good water to consumers. The purpose of the study was to obtain the basic data of control technology for water quality in pipes through investigating water quality in distribution system. We selected 11 sampling sites and investigated water quality from plant to endpoint of distribution system. we also simulated decreasing tendency of free chlorine through pipeline network. As the result of water quality test, all parameters were below allowable levels, but some parameters had the possibility of being over levels. So there must be more work to set up proper countermeasure for violable parameters.

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A Study on the Optimal Water Pricing by Long Run Marginal Cost in Korea (장기한계비용을 이용한 한국의 최적 수도요금결정에 관한 연구)

  • Kim, Tai-Yoo;Yoo, Seung-Hoon;Park, Chung-Hyun
    • Journal of Korean Society of Water and Wastewater
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    • v.10 no.3
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    • pp.100-114
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    • 1996
  • Besides insufficient water, water contamination confronts us with 'water crises' of both quantity and quality. However, the daily water consumption per capita of Korea is greater than that of other developed countries. Because of the current low water price, which is lower than a half of production cost, not only does it become difficult to cope promptly with rapidly increasing water demand and water contamination, but it also causes waste of water. We should, therefore, switch over from supply side management-oriented policy to demand side management-oriented policy through a raise of the water rate. This study carries out a cost analysis based on fair return method which is the principle of water pricing in Korea, and it estimates, through equilibrium analysis, long run marginal cost(LRMC), which satisfies allocative efficiency and reflects true social cost to additional one-unit water supply. Based on the results, this study proposes that the estimated LRMC is the optimal price level in water pricing, which is the most important of the demand side management policies. In the end, water conservation effect, price pervasive effect, and social welfare effect are analyzed.

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Water Quality Alteration during Passing through Small Water Tank and Improvement of Tap Water Quality by Direct Connection Service (옥상물탱크 경유에 따른 수돗물 수질 변화 및 직결급수방식 도입에 의한 수질개선 효과 연구)

  • Lee, Mok-Young;Chang, Hyun-Jung;Lee, Eu-Kwang;Oh, Se-Jong;Lee, Chae-Keun;Lee, Hyun-Dong
    • Journal of Korean Society of Water and Wastewater
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    • v.14 no.4
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    • pp.328-336
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    • 2000
  • In order to compare the effect of water quality on two service systems, tank and direct connection service, we selected randomly 30 rooftop tanks installed in the buildings with five or fewer floors, and collected water samples from each tank as well as tap water by direct service. At the same time each tank was investigated on their cleanliness and sanitary control. 30 water samples from direct service met Korean Drinking water quality standard. But 5 tank water samples(17%) were not able to meet Coliform or Total Colony Counts standard and free chlorine of 12 tank water samples(40%) were less than 0.2mg/L. Also Fe, Turbidity, TOC, Total Algae in tank water were higher than tap water on direct service. We concluded that thorough health control of water tank is necessary and conversion into direct connection service results in improving tap water quality importantly.

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A Technology for Water Pollution Diffusion Prevention based on Web Map

  • Shin, Jin Seob
    • Journal of the Korea Society of Computer and Information
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    • v.22 no.11
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    • pp.65-71
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    • 2017
  • An integrated water environment management system is necessary in improving water quality, properly allocating water resources, and supporting socio-economic development. Specifically, water quality management system using web map can be an efficient approach to accomplish this system. This paper aims to construct a dynamic water quality management system to reflect a water environment management system which includes three sub-models with consideration of their interrelationships (a socio-economic model based on dynamic Input-Output model, a water resources cycle model, and a water pollutants flow model). Based on simulation, the model can precisely estimate trends of water utilization, water quality, and economic development under certain management targets, and propose an optimal plan. This study utilized the model to analyze the potential of using reclaimed water to accomplish local water environment management and sustainable development plan while exploring the applicable approaches. This study indicates that the constructed water environment management system can be effective and easily adopted to assess water resources and environment while improving the trade-off between economic and environment development, as well as formulate regional development plan.

Selecting Characteristic Raman Wavelengths to Distinguish Liquid Water, Water Vapor, and Ice Water

  • Park, Sun-Ho;Kim, Yong-Gi;Kim, Duk-Hyeon;Cheong, Hai-Du;Choi, Won-Seok;Lee, Ji-In
    • Journal of the Optical Society of Korea
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    • v.14 no.3
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    • pp.209-214
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    • 2010
  • The Raman shift of water vapor is 3657 $cm^{-1}$, and this Raman signal can be easily separated from other Raman signals or elastic signals. However, it is difficult to make simultaneous Raman measurements on the three phases of water, namely, ice water, liquid water, and water vapor. This is because we must consider the overlap between their Raman spectra. Therefore, very few groups have attempted to make Raman simultaneous measurements even on two elements (water vapor and liquid water, or water vapor and ice water). We have made an effort to find three characteristic Raman wavelengths that correspond to the three phases of water after measuring full Raman spectra of water on particular days that are rainy, snowy or clear. Finally, we have found that the 401-nm, 404-nm, and 408-nm wavelengths are the most characteristic Raman wavelengths that are representative of the water phases when we are using the 355-nm laser wavelength for making measurements.

Status of Water Infrastructure and Future Tasks in Jeollabuk-do Province(Focussed on the Mangyeong River and Dongjin River) (전라북도 물이용 체계 및 과제(만경강과 동진강 중심으로))

  • Kim, Boguk
    • Journal of Korean Society of Water and Wastewater
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    • v.36 no.5
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    • pp.289-296
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    • 2022
  • Mangyeong River and Dongjin River are highly dependent on external regions for domestic and agricultural water, and the agricultural water supply and use system of those rivers are very complicated. For smooth water supply, rivers are used as a supply system. Of the total river water use permits (as of 2019), agricultural water accounts for 97.5%, 80.4% in Mangyeong River and Dongjin River, respectively. The excessive intake of river water as agricultural purpose is causing the stream to dry out and to deteriorate the ecological health of the river. It is necessary to minimize the water use system that takes in and utilizes river water. In both rivers, the flow rate of agricultural drainage and the load of major water quality items that flowing into the main stream are similar to or higher than those of the major tributaries, indicating that management is necessary to improve the water quality of the river. It is necessary to understand the effect of agricultural drainage on river water quality by establishing a continuous monitoring system for the form of agricultural drainage.

Effects of Water Restriction on the Growth Performance, Carcass Characteristics and Organ Weights of Naked Neck and Ovambo Chickens of Southern Africa

  • Chikumba, N.;Chimonyo, M.
    • Asian-Australasian Journal of Animal Sciences
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    • v.27 no.7
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    • pp.974-980
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    • 2014
  • In semi-arid areas of Southern Africa, dehydration can compromise the performance and welfare of local chickens, particularly during the growing period when confinement is curtailed and birds are left to scavenge for feed and water. The effect of water restriction on the growth performance was compared in Naked Neck (NNK) and Ovambo (OVB) chickens that are predominant in Southern Africa. A total of 54 eight-wk-old pullets each of NNK and OVB chickens with an initial average weight of $641{\pm}10g/bird$ were randomly assigned to three water intake treatments, each having six birds for 8 wk. The water restriction treatments were ad libitum, 70% of ad libitum and 40% of ad libitum intake. Nine experimental pens with a floor space of $3.3m^2$ per strain were used. The pens were housed in an open-sided house with cement floor deep littered with a 20 cm layer of untreated wood shavings. Feed was provided ad libitum. Average daily water intake (ADWI), BW at 16 weeks of age (FBW), ADG, ADFI, feed conversion ratio (FCR) and water to feed ratios (WFR) were determined. Ovambo chickens had superior (p<0.05) FBW, ADG and ADWI than NNK chickens. Body weight of birds at 16 weeks of age, ADG, ADFI, ADWI, and WFR declined progressively (p<0.05) with increasing severity of water restriction while FCR values increased (p<0.05) as the severity of water restriction increased. Naked Neck chickens had better FCR at the 40% of ad libitum water intake level than Ovambo chickens. The dressing percentage per bird was higher in water restricted birds than those on ad libitum water consumption, irrespective of strain. Heart weight was significantly lower in birds on 40% of ad libitum water intake than those on ad libitum and 70% of ad libitum water intake, respectively. In conclusion, NNK chickens performed better than OVB chickens under conditions of water restriction and would be ideal to raise for meat and egg production in locations where water shortages are a major challenge.