• 상하수도학회지
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• 제28권5호
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• pp.509-516
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• 2014

This study describes a reasonable planning method for water meter replacement which can minimize the metering under-registration for an increasement of revenue water. The increment analysis of real water usage was used to establish a replacement plan. The meter replacement database collected from K City was used as the basis of this analysis. The database included 964 connections of domestic and non-domestic consumers that had their meter replaced by aging at 2011. The result showed that the corelation between unregistered water volume and water meter age was lower than commonly expected where the current criteria of replacement is only water meter age(8 years) excluding the meters older than 13 years. And in the analysis result of water usage for 8 years, the total amount and increment of water usage had a significant effect on unregistered water volume. However the relation was different tendency as a total volume and slope of increment. In case of total water volume was larger than 10,000, larger than 7,000 and increment of 0.0 ~ -0.3, larger than 6,000 and increment more than -0.3 were analysed to need a replacement because of metering under-registration.

• 상하수도학회지
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• 제19권4호
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• pp.506-514
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• 2005

Unaccounted-for water subtracting water sold from produced water includes leakage, under-registration, unauthorized use, etc. To improve accounted-for water ratio, firstly, it should be attempted to accurately identify where unaccounted-for water is, and then it must to be reduced. Under-registration of meter is caused by allowable tolerance of meter, improper size of meter installed, gradient installation, etc. Under-registered water of meters has ever been the second large amount of unaccounted-for water next to leakage, but still is not estimated exactly. In this study, the estimated value as under-registered water was obtained by using the selected-area modeling program. As a result, the under-registered water ratio of 13mm meters was approximately 1.23%. Those of meters according to ages 1, 3, and, 5 years old were 1.46% 2.77% and, 2.26%, respectively but that of 7 years old meters showed over-registration of 1.59%.

• 상하수도학회지
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• 제19권5호
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• pp.582-594
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• 2005

The under-registration of water meters of 20mm to 50mm in diameter, installed in Seoul city, was estimated by random sample method. The sample sites and sampled meters were selected for the measurements of flow rates and accuracy tests, respectively. The measurement of flow rates was conducted for 20mm to 50mm meters for about 20 days per site using flow meters and data loggers. The under-registration of 20mm, 25mm, 32mm, 40mm, and 50mm meters was observed as 3.96%, 1.10%, 2.47%, 4.04%, and 1.04%, respectively. The under-registration might be increased more or less as malfunction and failure of the sampled meters was not considered. In this study the under-registration of 20mm, 25mm, 32mm, 40mm, and 50mm meters was accurately estimated on the basis of the investigation data. The estimation of under-registration of water meters, one of the basic figures in water industry, contributed to accurate calculation of leakage, water supply and consumption, and strategic planning to reduce the unaccounted-for water.

• 한국토양비료학회지
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• 제20권3호
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• pp.241-249
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• 1987

들깨의 수량(收量) 유지함량(油脂含量) 및 유지조성(油脂組成)에 대한 인산(燐酸), 석회(石灰), 가리(加里)의 영향(影響)을 조사(調査)한 결과(結果)는 다음과 같다. 1. 인산시용시(燐酸施用時) 들깨의 수량증대효과(收量增大效果)가 가리(加里)와 석회(石灰)의 경우보다 더 컸었다. 2. 유지함량(油脂含量)에 대한 인산(燐酸)과 석회(石灰)의 효과(效果)는 없었으나 가리(加里)의 효과(效果)는 인정(認定)되었다. 3. 인산시용(燐酸施用)은 triglyceride의 함량(含量)을 증대(增大)시켰으며 특(特)히 인산(燐酸)+가리(加里)+석회구(石灰區)에서 92.1%로서 최대함량(最大含量)이었다. 4. 들깨유지(油脂)의 지방산조성중(脂防酸組成中) linolenic acid의 함량비율(含量比率)이 최대(最大)이었으며 그외 palmitic, oleic, linoleic acid가 주요지방산(主要脂肪酸)이었다. 5. 가리(加里)를 시용(施用)치 않고 인산(燐酸)과 석회(石灰)만의 시용시(施用時) linolenic acid의 함량비율(含量比率)의 감소(減少)와 더불어 불포화도(不飽和度)가 낮았으나 가리(加里)를 혼용(混用)할 시에 회복(回復)되었다. 6. 4-desmethyl sterol 분획(分劃)이 들깨유지(油脂)의 불감화물의 대부분(大部分)을 구성(構成)하였으며, 주요(主要) sterol로서 campesterol, stigmasterol, sitosterol이 동정(同定)되었고 이들중(中) sitosterol의 함량(含量)이 전(全) 처리구(處理區)에서 최대(最大)이었다. 7. 시용비종(施用肥種)에 따른 sterol 조성(組成)의 변화(變化)는 특별(特別)한 경향(傾向)을 보이지 않았다.