• Title, Summary, Keyword: Water Intake

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Water Quality Improvement in the River through Reformation of Irrigation Water Supply Systems (관개용수 공급체계 변경을 통한 하천의 수질개선)

  • Lee, Kwang-Ya;Kim, Hae-Do;Lee, Jong-Nam;Park, Jong-Hoon
    • Proceedings of the Korea Water Resources Association Conference
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    • pp.540-545
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    • 2006
  • The objective of the study is to assess the water quality improvement resulted from the rearrangement of the irrigation water supply systems at Mankyeong River and Ansung Chun basin. There is a mixed type of watershed composed of urban and rural areas in the region. The water intake facilities for agricultural use such as reservoir, weir and pumping station are generally located at upstream river where the water quality maintains relatively clean. However, this study focuses on moving the water intake to downstream and rearranging the irrigation water supply system, then investigating how effective they are for water quality improvement in the river. When the water intake is moved downstream, the stream flow is increased as much as the amount of irrigation water that is to be taken upstream. The augmented flow which is frequently referred to as environmental flow can function as dilution water for improving the quality of polluted water that is originated from the wastewater in tributaries.

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Experimental study of dynamic interaction between group of intake towers and water

  • Wang, Haibo;Li, Deyu;Tang, Bihua
    • Earthquakes and Structures
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    • v.6 no.2
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    • pp.163-179
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    • 2014
  • Dynamic test with scaled model of a group of intake towers was performed to study the dynamic interaction between water and towers. The test model consists of intake tower or towers, massless foundation near the towers and part of water to simulate the dynamic interaction of tower-water-foundation system. Models with a single tower and 4 towers were tested to find the different influences of the water on the tower dynamic properties, seismic responses as well as dynamic water-tower interaction. It is found that the water has little influence on the resonant frequency in the direction perpendicular to flow due to the normal force transfer role of the water in the contraction joints between towers. By the same effect of the water, maximum accelerations in the same direction on 4 towers tend to close to each other as the water level increased from low to normal level. Moreover, the acceleration responses of the single tower model are larger than the group of towers model in both directions in general. Within 30m from the surface of water, hydrodynamic pressures were quite close for a single tower and group of towers model at two water levels. For points deeper than 30m, the pressures increased about 40 to 55% for the group of towers model than the single tower model at both water levels. In respect to the pressures at different towers, two mid towers experienced higher than two side towers, the deeper, the larger the difference. And the inside hydrodynamic pressures are more dependent on ground motions than the outside.

Effect of Soy Isoflavone Intake on Water Maze Performance and Brain Acetylcholinesterase Activity in Rats (대두 이소플라본 섭취가 흰쥐에서 미로수행능력과 뇌 중 Acetylcholinesterase 활성에 미치는 영향)

  • Oh Hyun-Kyung;Kim Sun-Hee
    • Journal of Nutrition and Health
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    • v.39 no.3
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    • pp.219-224
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    • 2006
  • This study was performed to determine the effect of soy isoflavones on brain development and function in rats. Forty Sprague-Dawley male rats were provided diets containing different levels of soy isoflavones for 6 weeks; 0 ppm (control), 50 ppm (low isoflavone intake; LI), 250 ppm (medium isoflavone intake; MI) and 500 ppm (high isoflavone intake; HI). Learning ability was evaluated by a Y-shaped water maze and the activity of acetylcholinesterase in brain was assayed after decapitation. Food intake and body weights as well as weights of brain, liver, spleen, heart and kidney showed no significant difference among the four groups, which means 500 ppm of isoflavones is safe. In the water maze test, the frequency of error counted when rats entered one end of the alley without platform was significantly lower in the HI group than in the control group, and the escape latency as swim time taken to escape on the hidden platform was significantly shorter in the HI group than in the LI and control groups. The activity of acetylcholinesterase of the brain was significantly higher in the HI and MI groups than in the control group. Therefore, the results indicate that isoflavones may improve the cognitive function without adverse effects.

A Study on the Water Resources Assessment for Irrigation Scheme in Malawi

  • AHN, SungSick;Kim, Jin-Hong
    • International Journal of Advanced Culture Technology
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    • v.6 no.3
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    • pp.178-186
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    • 2018
  • Generally, in terms of the development of irrigation scheme, the efficient water resource management that supplies the irrigation water in consideration of the required time and accurate quantity to grow the crop should be conducted. The water resource assessment should precede to supply the irrigation water efficiently. The water resources assessment is divided into the water requirement analysis and the water availability assessment. In case of Korea, the major crop is paddy rice unlike crops of Africa, such as sugarcane, maize, and cassava, etc. Because it is not familiar with the method for upland irrigation development in tropical area, it needs to know the water resources assessment for irrigation scheme development about these crops. The Natama Scheme in Chiradzulu District of the Southern Malawi was selected as study area, which has tropical climate. From the collected meteorological data, the evapotranspiration was analyzed by Penman-Monteith Method and the effective rainfall was analyzed by USDA Soil Conservation Service Method. This study displays the results that for study area, the evapotranspiration varies from 2.80 mm/day to 5.51 mm/day and the effective rainfall varied from 2.1mm to 149.0mm. According to the selected crop (Green Maize, Dry Maize), the unit water requirement (UWR) and water demand (WD) considering the irrigation efficiency, irrigation time and irrigation area were estimated to be $0.00122m^3/s/ha$ and $0.0122m^3/s$ respectively. For the water availability assessment, the runoff of Natama scheme was calculated by specific yield method. The water availability was evaluated through reviewed differences of discharge between $Q80_{intake}$ and Total WD, and the irrigation water can be supplied sufficiently in the existing 10ha of Natama scheme. As a result of reviewing the extensibility of irrigable area, total WD of scheme is $0.02313m^3/s$, and $Q80_{intake}$ is $0.02387m^3/s$ ($Q80_{intake}$ > Total WD). Therefore, Natama scheme can be extended from 10 ha to 17 ha in the dry season in consideration of the $Q80_{intake}$.

Prechlorination at Water Intake for the Quality Improvement of Raw Water (상수원수 수질개선을 위한 취수장 전염소 투입에 관한 연구)

  • Kim, Daehyun;Hwang, Suok;Jeong, Eunjae;Shin, Changsoo;Yu, Youngbeom;Hong, Seungkwan
    • Journal of Korean Society on Water Environment
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    • v.27 no.1
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    • pp.110-114
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    • 2011
  • In this paper, in order to eliminate Limnoperna fortunei inhabiting the water conduction pipeline, prechlorination at the intake station was employed to improve the degradation of water quality due to the high pH of raw water taken at the downstream of Paldang Dam, algal growth, etc.. With the prechlorination concentration of 1.0mg/L at the intake station, the pH in the water well at the treatment plant decreased by 0.4, and with 1.5mg/L, by 0.6. Also, it eliminated Chlorophyll-a by about 95%, and the population of algae by about 49%. Such disinfection by-products (DBPs) as Trihalomathanes (THMs), Haloacetic Acids (HAAs), and Chloral Hydrate (CH) were under the quality standard for potable water, showing no change by the prechlorination, while raising the prechlorination rate from 1.0 up to 1.5mg/L, the DBPs in the water well increased by 1.5 to 3.1 times. As a consequence of testing Kyungan Stream, a branch stream flowing into Lake Paldang, the prechlorination (0.57mg/L, 1.14mg/L, 1.71mg/L) had no effect of eliminating the taste and odor compounds and total organic carbon (TOC) which is the DBPs precursor. As for the efficiency of Geosmin elimination by the rates of prechlorination and powder activated carbonation (PAC), it was found that the higher the concentration of PAC was (30ppm>20ppm>10ppm), the higher the efficiency was; the higher the rate of prechlorination was, the lower the efficiency by PAC was. Therefore, when taste and odor occur from raw water, suspending prechlorination at the intake or lowering the rate was proved to be more effective in eliminating the taste and odor compounds by PAC.

WATER DRINKING BEHAVIOUR OF STEERS FED EITHER FRESH CUT FORAGE OR FIRST CUT HAY

  • Sekine, J.;Morita, Z.;Oura, R.;Asahida, Y.
    • Asian-Australasian Journal of Animal Sciences
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    • v.1 no.3
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    • pp.157-161
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    • 1988
  • To study the effect of moisture content of the diet on drinking behaviour and the amount of water drunk, observations were made on 8 Holstein steers fed either fresh cut forage or first cut hay. The observations were made in a barn with a mean temperature of about $13^{\circ}C$. Drinking occurred mainly within 3 hours after feeding for the steers fed hay, while those fed soilage drank casually. Frequency of drinking (F) was related to the dry-matter concentration (DMC, %) of herbage: F = 0.47 (${\pm}0.09$) DMC - 6.5, $SE={\pm}0.4$, r = 0.86, P<0.01. Intake of drinking water for each 100 kg of live weight (IDW/100kg) for steers fed soilage was related to the dry-matter concentration: IDW/100kg = 0.55 (${\pm}0.06$) DMC - 8.7, $SE={\pm}0.3$, r = 0.94, P<0.01. The intake of water in each drinking period for animals fed fresh forage was curvilinearly related to the drinking frequency; for the hay-fed steers there was a negative linear relationship. When the drinking frequency for steers fed the fresh forage increased to the same as that observed for the hay, water intake in each drinking period was the same as found for the hay-fed steers.

Practical Experiences with Corrosion Protection of Water Intake Gates in Mekong River

  • Phong, Truong Hong;Tru, Nguyen Nhi;Han, Le Quang
    • Corrosion Science and Technology
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    • v.7 no.6
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    • pp.328-331
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    • 2008
  • Corrosion behaviour of water intake gate steel structures with different protective measures was investigated. Five material alternatives were taken for investigation, including: imported and recycled stainless steel, carbon steel with hot zinc spraying, painting and composite coatings. Results of corrosion rate for carbon steel, SUS 304, hot zinc spray coats in three water systems of Mekong river basin (saline, blackish and fresh) were also presented. Corrosion rate of carbon steel decreased with decreasing salinity in the investigated water environments. Meanwhile, these values for zinc coated steel, behaved by another way. Environmental data for these systems were filed and discussed in relation with corrosion characteristics. Method of Life Cycle Assessment (LCA) was applied in materials selection for water intake gate construction. From point of Life Cycle Cost (LCA) the following ranking was obtained: Zinc sprayed steel < Recycled stainless steel < Composite coated steel < Painting steel < SUS 304 From investigated results, hot zinc spray coating has been applied as protective measure for steel structures of water intake systems in Mekong river basin.

Water Storage and Intake Performance of Gabion Weirs during Recharge (인공함양 원수확보를 위한 돌망태 보의 저류 및 취수성능에 관한 연구)

  • Han, Il Yeong;Kim, Gyoo Bum
    • The Journal of Engineering Geology
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    • v.29 no.4
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    • pp.393-403
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    • 2019
  • The water-storage performance of an intake weir can be evaluated by stage-discharge ratings. The stage-discharge rating of a gabion weir depends on the physical characteristics of the filling materials. This study reviewed existing discharge formulae for the evaluation of the water-storage performance of gabion weirs. A previously published relationship between the characteristics of filling materials and experimental constants was adapted for stage-discharge rating. The mean size of the filling material is the most influential factor for the water intake and water-storage performance of gabion weirs.

An Experimental Study of the Effects of Water Vapor in Intake Air on Comvustion and knock Characteristics in a Spark Ignition Engine (흡기중 수증기 함량이 스파크 점화기관의 연소 및 노킹에 미치는 영향에 관한 실험적 연구)

  • 이택헌;전광민
    • Transactions of the Korean Society of Automotive Engineers
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    • v.6 no.1
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    • pp.205-212
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    • 1998
  • In this study, the effects of water vapor in inlet air on combustion efficiency, general performance, knock characteristics and emission gas concentration were investig- ated through the experiments of combustion and vibration analyses, emission gas analysis by changing water vapor quantity in inlet air with temperature and humidity auto control unit. With partial vapor pressure increase, the brake torque at wide open throttle status decreased and the average ignition delay angle increased, IMEP (indicated mean effective pressured using the integral and 3rd derivatives of filtered cylinder pressure as knock intensity, which matched well with the method of frequency power spectrum of block vibration signal. Water vapor in intake air had influence on the spark knock sensitivity. With the increase of water vapor content in intake air NOx emission was decreased and HC emission was increased.

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