• Parasites, Hosts and Diseases
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• 제43권2호
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• pp.47-50
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• 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.

• 한국태양에너지학회 논문집
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• 제22권2호
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• pp.11-17
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• 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.

• 한국환경과학회지
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• 제14권6호
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• pp.533-542
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• 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.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 추계학술대회논문집B
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• pp.268-273
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• 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.

• 수산해양교육연구
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• 제18권3호
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• pp.293-301
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• 2006

연속식 스테인레스 단자 방식의 전해수의 기기특성과 오징어를 담수빙과 산성전해수빙, 염기성전해수빙 저장 중 선도보존 효과 및 표피색변화에 대하여 검토하여, 향후 연안 어류의 전기분해수 빙장 적용기초 자료로 이용하고자 연구한 결과를 요약하면 다음과 같다. 1. 본 연구에서는 TMD에서 개발된 기기에 단자를 구리에서 스테인레스로 교체한 TMD II기기의 성능을 평가하였다.실험결과 전체적으로 동일한 전류를 걸었을때, 산성전해수의 경우 낮은 pH를 유지했으며, 유량을 늘릴수록 산성도가 떨어지는 것을 알 수 있었다.본 장치는 단자부분 재질의 감도를 보다 높이고 전해 촉매제를 사용할수 있다면, 충분히 더 낮은 혹은 더 높은 pH를 확보할 수 있으며 또한 알카리 영역의 경우도 그럴 수 있으리라 예측된다. 2. 먹는물 수질기준에 따른 유속별 생산 전해수의 수질분석 및 미생물검사결과 세균학적인 검사의 경우 모든 검사과정에서 먹는물 기준 이하치를 나타내고 있으나 산성전해수의 경우 미생물학적인 검사에서 음성의 결과를 나타냈으나, 알카리수의 경우 중온성 세균수에 있어서는 먹는물의 수준은 될 수 없음을 알 수 있다. 3. 전해수빙과 담수빙 저장중 오징어의 일반성분과 VBN관찰 결과 수분 함량은 77.65%였으며 단백질 함량은 18.32%, 지질의 함량은 2.41%, 회분 함량은 1.62%로 나타났다. 오징어 빙장 직전 11.2mg/100g이었으며, 저장 초기에 모든 산성 전해수 빙장구에서 VBN 증가가 억제되었다.담수빙 법에서의 VBN 증가가 전해수빙중 산성수빙보다 훨씬 빠르게 진행되었으며 염기성수빙 보다는 느리게 진행되었다. 4. 저장중 오징어의 외관 및 색도 변화를 색차계로 저장시간별로 측정한 결과, 명도(L)는 저장시간별로 감소하는 경향이었으며, 적색도, 황색도는 저장방법에 따른 차이는 있었지만 저장기간에 따라서 증가하는 경향을 보였다. 즉, 저장시간별로 적색에서 녹색으로 청색에서 황색으로 색깔의 변화가 진행됨을 알 수 있었다. 백색도의 경우도 명도와 비슷한 경향 이었다.

• 한국농공학회논문집
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• 제58권2호
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• pp.65-71
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• 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.

• 한국산림과학회지
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• 제85권1호
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• pp.66-75
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• 1996

본 연구는 산불 발생이 임지의 수저류 특성에 미치는 영향을 알아보기 위해 실시했다. 비산불 지역과 산화적지를 대상으로 산림토양의 수저류능을 토양공극, 최대수분량, 이용가능수량, 그리고 투수율을 측정하여 비교 분석하였다. 주요 인자들의 측정에 의해서 얻어진 결과는 다음과 같다. 산화적지와 대조구에서 토성이 깊어질수록 전공극(全孔隙), 조공극(組孔隙), 이용가능 수량, 투수율은 모두 감소하는 경향을 나타내고, 세공극(細孔隙)은 약간 증가하는 경향이 있었다. 대조구에 비해 산화적지에서는 투수율, 조공극량 및 이용가능수량이 낮게 나타나는 반면, 세공극량은 높게 나타났다. 그리고 산불이 발생한 직후에는 산림토양의 공극량 분포에 큰 변화가 일어나지 않지만, 시간이 경과함에 따라 산화적지의 표토 공극분포에 변화를 일으키면서 서서히 토심 20-40cm까지 영향을 미치는 것으로 나타났다. 또한 토심변화에 따른 이용가능수량의 변화는 대조구에 비해 산화적지에서 상대적으로 큰 폭으로 감소하는 경향이 있었다. 이 결과로 산림의 수저류능은 산불에 의해 크게 영향을 받는 것을 알 수 있었다.

• 태양에너지
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• 제9권3호
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• pp.37-43
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• 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.

• 한국태양에너지학회 논문집
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• 제33권5호
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• pp.82-88
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• 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.

• 한국환경보건학회지
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• 제33권6호
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• pp.517-521
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• 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.