• 조명전기설비학회논문지
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• 제21권6호
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• pp.71-76
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• 2007

본 논문에서는 상용전원이 침수되었을 경우, 이에 의한 인체 감전의 위험성을 실증실험을 통해 검토하였다. 실험을 위해 한쪽 벽면에 노출된 충전부가 설치된 모의수조를 구축하고 내부에 도전성 수용액을 채운 후, 전원으로부터의 거리, 방향, 도전성 수용액의 전도율 및 수위에 따른 전위를 측정하였다. 실험 결과 수중에 설치된 전원장치로 인한 전위분포는 거리에 따라 달라지지만, 침수 수용액의 도전율, 노출된 충전부로부터의 각도 및 측정높이는 전기적으로 미치는 영향이 거의 없음이 확인되었다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제27권2호
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• pp.87-98
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• 2022

This study aims to prepare a technical protocol for identifying the source of nitrate in water using nitrogen (δ¹⁵N) and oxygen (δ¹⁸O) stable isotope ratios. The technical processes for nitrate sources identification are composed of site investigation, sample collection and analysis, isotope analysis, source identification using isotope characteristics, and source apportionment for multiple potential sources with the Bayesian isotope mixing model. Characteristics of various nitrate potential sources are reviewed, and their typical ranges of δ¹⁵N and δ¹⁸O are comparatively analyzed and summarized. This study also summarizes the current knowledge on the dual-isotope approach and how to correlate the field-relevant information such as land use and hydrochemical data to the nitrate source identification.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2007년도 동계학술발표대회 논문집
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• pp.434-440
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• 2007

The Effluent ground water overflows in deep and broad ground space building. Temperature of effluent ground water is in 12$\sim$18$^{\circ}C$ annually and the quality of that water is as good as living water. Therefore if the flow rate of effluent ground water is sufficient as source of heat pump, that is good heat source and heat sink of heat pump. Effuent ground water contain the thermal energy of surrounding ground. So this is a new application of ground source heat pump. In this study open type and close type heat pump system using effluent ground water was installed and tested for a church building with large and deep ground space. The effluent flow rate of this building is 800$\sim$1000 ton/day. The heat pump capacity is 5RT each. The heat pump system heating COP was 3.0$\sim$3.3 for the open type and 3.3$\sim$3.8 for the close type system. The heat pump system cooling COP is 3.2$\sim$4.5 for the open type and 3.8$\sim$4.2 for close type system. This performance is up to that of BHE type ground source heat pump.

• 한국환경보건학회지
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• 제29권1호
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• pp.19-27
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• 2003

Coliforms is currently being used as the standard of environmental water qualify to evaluate the level of source water quality especially condition of fecal contamination. However, not properly applied to water quality management. So in this study, in addition to Coliforms, fecal contamination indicator bacteria turk at Feral Coliforms(FC), E. coli, Fecal streptococci(FS), Clostridium and environmental parameters related with it's distribution were investigated on a monthly basis in 6 water intakes of Han River. The mean of BOD, DO, SS and pH, benchmarks of source water management were maintained the second grade of environmental water quality standard applied to Han River but Coliforms exceeded it. Distribution of Coliforms ranged from 1.0×10¹ to 2.7 10/sup 5/ CFU/ml, FC ranged from ND to 5.3×10¹ CFU/ml, E. coli ranged from ND to 9.2×10¹ CFU/ml, FS ranged from ND to 2.5×10¹CFU/ml, they were steepy rise on July and August in common when rainfalls was heavy and water temperature was high, but Clostridium perfringens ranged from 1.7×10¹to 1.7×10¹CFU/ml not fluctuate by month. Statistical analysis of sampling data showed that most significant correlations occurred among FC and Coliforms(r = 0.840), E. coli(r = 0.792), FS(r = 0.687) and environmental parameters(temperature, turbidity, SS, rotor were all r > 0.60) while no significant correlation was observed between ammonia generally recognized fecal contamination indicator and bacteria. Identification of the coliforms showed that Enterobacter, Klebsiella, Citrobacter were comprised of 32%, 24%, 16% respectively, and E. coli were 7% of it. while E. coli was made up 85.9% of FC. The mean value of FC/Coliforms ratio, 5.2(0.1-42) were higher in Amsa, Guui than Jayang. Fecal coliforms, as those are able to reflect more particularly the extent of the fecal contamination, were considered useful in deciding the level of water treatment while monitoring the fecal contamination from the source of water supply. Therefore, it is expected that the water quality is going to be managed more efficiently by using fecal coliforms supplementarily to total coliforms which are current standard item of water-quality environment.

• 한국물환경학회지
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• 제20권6호
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• pp.657-663
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• 2004

The aims of this study are the characterization of runoff from nonpoint source, the analysis of the pollutant loads and an establishment of a management plan for nonpoint source of Okcheon. For this purpose the basin of the stream So-okcheon was selected to the investigated. During the period from May 29 to July 21 in 2003, the water automatic sampler system has been installed in Okkagkyo and parameters such as SS, COD, TOC, TP and TN were analyzed. The pollutants of nonpoint source seem to be washed out along the stream water in the beginning of rainfall, remain in water and cause the stream pollution. The runoffs during heavy rainfall, especially, much higher concentration of SS than those during dry period. With respect to the annual loading of pollutants of the nonpoint source, the COD was 124 ton/yr, TOC 396 ton/yr, TN 1,429 ton/yr and TP 4.2 ton/yr in the year 2002. With respect to the pollutants loading of the nonpoint source, the COD was 375 ton/yr(95% of the total COD loading of 394 ton/yr), TOC 844 ton/yr(96% of the tatal TOC loading of 876 ton/yr), TN 1,985 ton/yr(96% of the total TN loading of 2,062 ton/yr) and TP 37.1 ton/yr(92% of the total TP loading of 40.3 ton/yr) in the year 2003.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2002년도 전력전자학술대회 논문집
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• pp.257-262
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• 2002

Water-Electrolyzed gas is a mixed gas has the constant volume ratio 2 1 Hydrogen and Oxygen gained from electrolyzed water, and it has better characteristics in the field of economy, efficiency of energy, and environmental intimacy than acetylene gas and LPG used for existing gas welding equipment. So nowdays many studies of Water-Electrolyzed gas are progressed, and commercially used as a source of thermal energy for gas welding in the industry. For Water-Electrolyzed Source, it was used diode rectifier or SCR rectifier for get DC source. This method which is not looking to improve a source for impossible current control or voltage and limited control intervals. In this paper, it was relized and designed In source of pulse type for complementing existing - DC source type, also by experiment it was acquired producting characteristics of Hydrogen -Oxygen Gas through feature of source

• 설비공학논문집
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• 제21권8호
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• pp.468-474
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• 2009

Ground water source heat pump system is the oldest one of the ground source heat pump systems. Despite of this, little formal design information has been available until recently. The important design parameters for open system are the identification of optimum ground water flow, heat exchanger selection and well pump. In this study, the capacity of 50 RT system of two well type ground water heat pump system was used. As a result, static water level was -7 m and the level during the heating operation was -32 m, cooling operation was -40 m. The initial static water level recovered within 48 hrs. The temperature of ground water is $15.6^{\circ}C$ for heating season and $16.2^{\circ}C$ for cooling season and does not depend on the outdoor temperature. Operation efficiency of the system shows that, COP 3.1 for heating and COP 4.2 for cooling.

• 한국농공학회:학술대회논문집
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• 한국농공학회 2005년도 학술발표논문집
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• pp.637-642
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• 2005

The objective of this study is to evaluate design parameters of free water surface constructed wetland for the reduction of agricultural nonpoint source pollution. From literature review, the key design parameters were selected as influent concentration, influent water volume, hydraulic retention time and wetland system arrangement. The design value for each parameter was established after pilot study. Full-scale constructed wetland on the basis of the designed values was constructed to evaluate those reasonableness. The results of this study showed that the designed values for free water surface constructed wetland were appropriate for the reduction of agricultural nonpoint source pollution.

• 환경위생공학
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• 제15권1호
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• pp.88-94
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• 2000

The purpose of this study was to analyze and compare the contents of minerals and ionic components in domestic commercial natural mineral waters, and to investigate the relationship between water quality and characteristics of suspended and rocks there of its source. All mineral waters tested in this study met the korean mineral water quality guideline, although chemical components varied widely depending upon the geological characteristics and degree of urbanization of the source area or physical water treatment method. The water quality of commercial bottled water was different from that of source water, especially in cationic components, and showed a tendency to become worse with time elapsed. The water quality on the bottle was also different from the measured quality.

• 한국수자원학회논문집
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• 제38권11호
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• pp.927-935
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• 2005

강우에 따른 토사유실은 호소내 저수용량 감소 및 탁수 등의 수질오염을 유발하기 때문에 유역관리 측면에서 중요한 인자가 된다. 최근 GIS를 활용한 토사유실평가 연구가 진행되고 있으나, 토사유실 원인지역에 대한 검토는 고려하지 않고 있다. 본 연구에서는 GIS 기반 토사유실모델을 활용하여 임하호 유역의 토사유실량을 산정하였으며, SPOT 5 고해상도 위성영상과 토지피복도 자료를 활용하여 토사유실원인지역을 검토하였다. 분석결과 토사유실이 높게 나타나는 지역의 대부분이 밭으로 확인되었으며 그 위치를 영상에서 효과적으로 확인할 수 있었다. 또한 위성영상에서 경계를 확인하기 곤란했던 밭과 과수원이 공통으로 나타나는 지역은 현장확인을 통해 그 적정성을 검토할 수 있었다.