• Title/Summary/Keyword: water storage

Search Result 3,783, Processing Time 0.039 seconds

The role of domestic tap water in Acanthamoeba contamination in contact lens storage cases in Korea

  • JEONG Hae Jin;YU Hak Sun
    • Parasites, Hosts and Diseases
    • /
    • v.43 no.2 s.134
    • /
    • pp.47-50
    • /
    • 2005
  • A survey was carried out from August to December 2004 in Pusan, Korea to document the presence of free-living amoeba (FLA), including the genus Acanthamoeba, in both contact lens storage cases and domestic tap water. Acanthamoeba was isolated from $5(4.2\%)$ in 120 contact lens storage cases. Four house tap water samples from residents, whose contact lens storage cases had been contaminated by Acanthamoeba, were also found to be contaminated with Acanthamoeba. Therefore, the contamination rate of FLA and Acanthamoeba in domestic tap water was investigated in order to examine the role of domestic tap water in Acanthamoeba contamination of contact lens storage cases. FLA and Acanthamoeba were identified in $97(46.8\%)\;and\;16(7.7\%)$ of the 207 domestic tap water samples, respectively. There were no significant differences between the contamination rates of FLA in tap water according to the filtration plant of origin. No FLA was detected in the tap water directly supplied by the water purification plants. Water storage tanks appear to promote FLA colonization, including Acanthamoeba, in domestic tap water. This increases the risk of Acanthamoeba contamination in contact lens storage cases as well as increasing the risk of Acanthamoeba keratitis.

Experiment on the Charge and Discharge of Thermal Energy for Under-Water Harvest-Type Ice Storage System (수중 하베스트형 빙축열시스템의 축방냉 특성 실험)

  • Kim, J.D.
    • Journal of the Korean Solar Energy Society
    • /
    • v.22 no.2
    • /
    • pp.11-17
    • /
    • 2002
  • This paper is concerned with the development of a new method for making, separating ice and storage floated ice by installing an evaporation plate at under-water within a storage tank. In a conventional harvest-type ice storage system, a tank saves ice by separating an ice from an installed evaporation plate, which is located above an ice storage tank as an ice storage system. Developed new harvest-type method shows good heat transfer efficiency than a convectional method. It is because the evaporation panel is directly contacted with water in a storage tank. Also, at a conventional system a circulating pump, a circulating water distributor and a piping are installed, however these components are not necessary in a new method. In this study ice storage systems are experimentally investigated to study the charge and discharge of thermal energy. The results show the applicable possibility and performance enhancement of a new type.

Parallel reservoirs system operation using NYC-Space Allocation-Rule (NYC-Space Allocation Rule을 이용한 병렬저수지 연계운영)

  • Park Ki-Bum;Lee Soon-Tak
    • Journal of Environmental Science International
    • /
    • v.14 no.6
    • /
    • pp.533-542
    • /
    • 2005
  • In this study, an optimization technique was developed from the application of Allocation Rule. Average Allocation coefficients of the Andong and Imha dam compare constant water supply condition with vary water supply condition that are above the contribute ratio $67\%\~50\%$ the Andong dam in Rule(A)-Rule(C). In the Refill Season, Andong dam water supply contribution is higher than Imha dam at the Control point water supply. In the Allocation analysis results, Rule(A) is calculated storage ratio because Andong dam contribute to Control point larger than Imha dam which Andong dam storage is larger than Imha dam storage. Rule(B) calculated sum of the storage and inflow ratio for Andong dam and Imha dam, as Andong dam contribution is higher than Imha dam. Rule(C) calculated that sum of storage, inflow and water supply is divided average storage ratio, as the best results of the Allocation coefficients and water supply capacity. The results of storage analysis is larger vary water supply condition than constant water supply condition and the results of water supply analysis is larger vary water supply condition than constant water supply condition. Water supply deficit is decrease $30\%$ for vary water supply condition.

Experiment of Characteristic on the Charge and Discharge of Cold for In-Water Harvest-Type Ice Storage System (수중 하베스트형 빙축열 시스템의 축방냉 특성)

  • Jang, Y.S.;Choi, I.S.;Moon, C.G.;Chun, S.H.;Kim, J.D.;Yoon, J.I.
    • Proceedings of the KSME Conference
    • /
    • 2001.11b
    • /
    • pp.268-273
    • /
    • 2001
  • A fundamental study on the harvest-type ice storage system applied ice making method in-water and its temperature characteristics in ice storage system was performed experimentally of the charge and discharge of cold. This paper is concerned with the development of a new method for making and separating ice and saving floated ice by installing an evaporation plate at in-water within a storage tank. In a conventional harvest-type ice storage system, a tank saves ice by separating a formed ice from an installed evaporation plate, which is located above an ice storage tank as an ice storage system. A new harvest-type method shows very good heat transfer efficiency than a convectional method. It is because the evaporation panel is directly contacted with water in a storage tank. Also, at a conventional system a circulating pump, a circulating water distributor and a piping are installed, but these components are not necessary in a new method. In this study two kinds of ice storage systems are experimentally investigated to study the thermal characteristics of ice storage tanks.

  • PDF

Water Properties of Electrolytic Machine by Stainless Diaphragm and Effects of Electrolytic Ice Water Storage For Keeping Freshness of Squid, Todarodes pacificus (스테인레스 극판을 이용한 전해수장치의 수질특성과 오징어 선도유지를 위한 전해수 빙장 효과)

  • Lee, Nahme-Gull
    • Journal of Fisheries and Marine Sciences Education
    • /
    • v.18 no.3
    • /
    • pp.293-301
    • /
    • 2006
  • This study was undertaken to prolonging the freshness in Squid(Todarodes pacificus) on the effects of ice storage methods(tap water ice, electrolytic water ice) using stainless diaphragm electrolytic instrument and also test an efficiency of instrument. Basically, stainless diaphragm electrolytic instrument studied for changes of pH on difference water flow and ampere. The lower water flower and higher ampere made low pH on acid part of electrolytic instrument. Squid samples were stored in tap water ice, acid part of electrolytic water and base part of electrolytic water and used in studying the changes of VBN and skin color through storage. Acid water had strong sterilization effects and VBN was lower levels of acid water than the others. Base water had not sterilization effects. Tap water ice storage was more sterilizing effects than base water ice storage but less effects than acid water ice storage. Lightness of Squid skin showed getting decrease at storage of ice water of all storage methods but acid water ice storage showed more retarding than the other two storage. From these results, it could be suggested that acid electric water ice storage is effective in extendance the shelf-life of squid at chilled storage.

Evaluation of Agricultural Water Supply Potential in Agricultural Reservoirs (농업용 저수지에서의 농업용수 잠재능 평가)

  • Kim, Jin Soo;Lee, Jae Yong;Lee, Jeong Beom;Song, Chul Min;Park, Ji Sung
    • Journal of The Korean Society of Agricultural Engineers
    • /
    • v.58 no.2
    • /
    • pp.65-71
    • /
    • 2016
  • The new concept of agricultural water supply potential, which is mean annual turnover rate times unit storage capacity, was introduced for agricultural reservoirs. We investigated characteristics of mean annual turnover rate and unit storage capacity for agricultural reservoirs with storage capacity of over $1million\;m^3$. The curve of agricultural water supply potential represents change in mean annul turnover rate according to change in unit storage capacity. The mean annual turnover rate and unit storage capacity in the reservoirs with high minimum storage ratio are significantly higher than those in the reservoirs with low minimum storage ratio. Most of unstable water supply reservoirs showed low mean annual turnover rate or low unit storage capacity, indicating that mean annual turnover rate may be an index of stability degree for agricultural water use. The reservoirs with mean annual turnover rate of over 2 and unit storage capacity of over 0.8 m may be estimated as the stable water supply zone for 10 frequency dry year. The reservoirs with high agricultural water supply potential can belong to the wide range of stable water supply zone. The results suggest that relation between mean annual turnover rate and unit storage capacity may be used in evaluating stability degree for agricultural water supply in the reservoirs.

Effects of Forest Fire on the Water Storage Characteristics of Forest Land (산불이 임지(林地)의 수저류(水貯留) 특성(特性)에 미치는 영향(影響))

  • Lee, Heon Ho
    • Journal of Korean Society of Forest Science
    • /
    • v.85 no.1
    • /
    • pp.66-75
    • /
    • 1996
  • This study was carried out to examine the forest fire effect on water storage characteristics in the forests. Water storage capacity of the burned area was analyzed by several major factors, such as soil pore, maximum water content, effective water storage, and percolation rate. The results obtained from the analysis of major factors are as follows; The deeper soil depth, the less total pore, coarse pore, effective water storage, and percolation rate. However, fine pore increased slightly in both burned area and control plot. As compared with control plot, burned area showed lower percolation rate, coarse pore, and effective water storage, but higher values of fine pore. Directly after forest fire, the soil pore is little affected. But as the time passes, top soil structure changes and soil pore also is affected even in a deep soil. Estimated effective water storage was lower at top soil of Namcheon and at deep soil of Namha in all the burned areas, but slowly decreased in deep soil compared to control plots. Therefore it was concluded that forest water storage capacity was greatly affected by the forest fire.

  • PDF

Experimental Study on the Thermal Storage Efficiency Through Variable Porous Mainfolds in a Test Storage Tank (실험 저장조내의 유입구 형상변화에 따른 열 저장효율에 관한 실험적 연구)

  • Pak, Ee-Tong;Hwang, Sung-Il;Choi, Young-Il
    • Solar Energy
    • /
    • v.9 no.3
    • /
    • pp.37-43
    • /
    • 1989
  • This paper dealt with thermal storage efficiency due to difference ($T_{\infty}-Ti$) between the mean temperature of water in the storage tank [$0.5m{\times}0.5m{\times}1.0m$] and the temperature of water flowing into the tank, flow rate of water flowing into the tank and shape of porous manifold which water flow into the tank through. As results of experiments; (1) When the flow rate was constant and the diameter of porous section decreased by 8mm, 6mm, and 4mm, the thermal storage efficiency increased. (2) When the diameter of porous section was constant and the difference ($T_{\infty}-Ti$) between the mean temperature of water in the storage tank and the temperature of water flowing into the tank increased by -30, -20, -10, 5, 10, 15 ($^{\circ}C$), the thermal storage efficiency increased. (3) When the($T_{\infty}-Ti$) was constant and the flow rate decreased by 0.8, 0.4, 0.25(LPM), the thermal storage efficiency increased. (4) When the shape of porous section was rigid, the thermal storage efficiency was the most effective, and with establishing flexible porous section or mesh, the effective thermal storage efficiency was obtained.

  • PDF

The Experimental Research for the Use Characteristics of the Passive and Active type Domestic Solar Hot Water Systems (자연형 및 설비형 태양열 온수기의 이용특성에 대한 실험적 연구)

  • Lee, Dong-Won;Kwak, Hee-You
    • Journal of the Korean Solar Energy Society
    • /
    • v.33 no.5
    • /
    • pp.82-88
    • /
    • 2013
  • There are the stirring test and drain test in the daily performance test to determine the thermal performance of a domestic solar hot water system. The drain test is a test that measures the discharge heating rate while drain the hot water from the top of the storage tank and supply the city water to the bottom of the tank. From the perspective of the user, this drain test is more effective than the stirring test. In this study, the thermal performance were compared through the drain test for a passive type and an active type domestic solar hot water systems consisting of the same storage tank and collectors. At this point, a passive type was used the horizontal storage tanks, and an active type was used vertical storage tank. In the drain test, when the hot water drained up to the reference hot water temperature, an active type which have vertical storage tank represents excellent daily performance than a passive type which have horizontal storage tank regardless of weather conditions. The reason for this is because the vertical storage tank is advantageous to thermal stratification in the tank. After the drain test, the residual heat for the horizontal storage tank was much more than the vertical storage tank, but in the next day the amount of discharged heat were less than the those of vertical storage tank neither. Thus, the solar water heating system which have horizontal storage tank should be adopted preheating control method rather than separate using control method when connected with auxiliary heat source device.

A Study on the Microbiological Quality of Drinking Water and Changes During Storage

  • Kim, Jong-Gyu
    • Journal of Environmental Health Sciences
    • /
    • v.33 no.6
    • /
    • pp.517-521
    • /
    • 2007
  • To assess possible risks from the consumption of drinking water from various sources, a survey of the microbiological quality of tap water, commercial bottled drinking water which is exploited from natural mineral water, and natural spring water was conducted. A total of 4 different brands of commercial bottled drinking water, and 4 types of spring water from different sources, and tap water from 4 private houses were tested for four index microorganisms, and the microbial quality changes of the water during the storage at room temperature or refrigerated temperature for 7 days. Aerobic plate counts of all of the initial water samples were still within 100 CFU/ml (drinking water standard of Korea). Total coliforms, fecal coliforms, and E. coli were not detected in all of the water samples at initial. However, aerobic plate counts of three types of spring water and three types of bottled drinking water stored at room temperature showed higher levels than the standards in 5 days. Total coliforms were detected in three types of spring water after one day's storage at room temperature, and in one type of bottled drinking water after 5 days' storage. These results indicate that some of the spring water surveyed are not safe to drink, and the spring water and bottled drinking water after opening the lid should not be stored at room temperature, if they are used for drinking.