• Transactions of the Korean Society of Automotive Engineers
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• v.10 no.4
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• pp.60-68
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• 2002

Experiments have been conducted to investigate the effects of emulsified fuels on the spray characteristics and exhaust emissions in a diesel engine. Four different fuels were examined : diesel, emulsified fuels with water contents which were varied with 13, 15, and l7wt%. Characteristics of fuel spray were measured by an optical method, PLLIF(planar liquid laser induced fluorescence). Compared to diesel fuel, emulsified fuels which had relatively high kinematic viscosity showed smaller spray angle and longer spray tip penetration. The qualitative droplet distributions of emulsified fuels showed worse atomization process than that of diesel fuel. As the water contents were increased, PM and NOx could be reduced simultaneously. It was specially noted that the emulsified fuel with l7wt% water content was found to be the best in reducing rates, NOx 30% and PM 40%.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1993.10a
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• pp.1395-1404
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• 1993

Application of water-saving self-feeders can reduce water consumption of pigs by more than 50% . so the feeding-watering system one of the most important way of the reduction of the slurry. Bioactive deep litter housing can eliminate slurry. Matured urine, faeces and litter can use for the purposes of soil conditioning and fertilizing . Water-saving slurry handling technology can halve manure dilution so it can double the nutrient content of the slurry. By using of straw bale biofilter for reducing emissions of pig houses makes fattening of pigs possible close to populated area. Developed rate control system for slurry application make avoiding over-fertilization possible , can fulfill better the demand of nutrient of plants. By means of computer aided manure utilization system area distribution of soil characteristics can determinate . The system is suitable for planning the utilization of manure and slurry in environment -friendly way.

• Magazine of the Korean Society of Agricultural Engineers
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• v.10 no.1
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• pp.1413-1419
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• 1968

Yochon reservoir was consturcted with an original storage capacity of 202.7 chung-meters. This reservoir receives the water from watershed area of 933.0 chungbo and has irrigated area of 478.0 chungbo. In 1967 a detailed capacity survey of this reservoir was carried out by a new depth-recorder under the scheme of reservoir sedimentation of Agricultural Engineering Research Center. Significant findings are 1. The capacity of the reservoir for the water storage has been reduced by 8.9%(18.066 chung-meters out of the 202.7 chung-meters) since its construction, a period of just 39.0 years. 2. The sediment accumulation in the reservoir represents an average annual soil loss of 0.496mm depth(0.463 chung-meters) of soil from the watershed area of 933.0 chungbo. Eventually the capacity of the reservoir for the water storage will be reducing by about 25%(50.7 chung-meters out of the 202.7 chung-meters)in one hundred years since its construction. We have to set up controlling projects for those reservoir protections from the sediment, soil loss, and other failures. The depth recorder is very useful, convenient, and accurate machine for surveys of reservoir capacity and other river surveys.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.1
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• pp.20-24
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• 2001

This study was conducted to analyze the general components and to investigate sensory evaluation of hot water extract prepared by boiling at 10$0^{\circ}C$ for 3 hr with 4-fold water. The contents of total soluble soild, non-reducing sugar, total saponin, ash and total protein were 15.95%, 6.54%, 1.735, 0.33% and 0.40%, respectively. The contents of succinic, malic and acetic acid in the extracts were 111.48 mg%, 23.67mg% and 18.36mg%, respectively. The major free amino acids and minerlas of the extract were hydroxyproline 1,290.0 $\mu\textrm{g}$%, glutamic acid 456.2$\mu\textrm{g}$% and potassium 151.35 mg%, respectively. Bitter taste in the extract was not observed, whereas sweet, sour and astringent taste were observed.

• 한국지구물리탐사학회:학술대회논문집
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• 2003.11a
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• pp.711-715
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• 2003

For Taejon LNG Pilot Cavern being constructed to verify the technical aspects for storing LNG in lined rock cavern, efficiency tests of groundwater drainage system composed of many pumps and boreholes were performed around the cavern before and after the construction of concrete lining. Through evaluation of water balance and monitoring of pressures and flowrates, even if the present drainage system is very good for reducing water entries into the cavern, non-negligible water is still flowing in the floor of the cavern concrete due to heavy rainfall. To improve the drainage efficiency, additional drainage holes and some grouting were planned.

• Journal of the Korean Ceramic Society
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• v.46 no.4
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• pp.365-371
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• 2009

It is well known that the properties of concrete such as the compressive strength, water permeability, water tightness and durability are affected by micro-structure in hardened cement paste. Especially, for durability of concrete, watertightness of cementitious materials is the most critical property among various properties. Recently, many types of materials as organic and/or inorganic materials are used for watertightness of concrete. In this study, The effect of Stearic Acid at $0.5\;wt%{\sim}3.0\;wt%$ adding ratios on the hydration and watertightness property of cement were investigated. And we also discussed the changing of microstructure in hardened cement paste by addition of Stearic Acid. Cement paste with Stearic Acid showed improvement of watertightness by reducing of cement total pore volume and decomposition of Stearic Acid.

• Journal of Advanced Marine Engineering and Technology
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• v.28 no.8
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• pp.1225-1238
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• 2004

The present study has been performed for obtaining the melting heat transfer enhancement characteristics of water mixture slurries of plural microcapsules having different diameters encapsulated with solid-liquid phase change material(PCM) flowing in a pipe heated under a constant wall heat flux condition. In the turbulent flow region, the friction factor of the present PCM slurry was to be lower than that of only water flow due to the drag reducing effect of the PCM slurry. The heat transfer coefficient of the PCM slurry flow in the pipe was increased by both effects of latent heat involved in phase change process and microconvection around plural microcapsules with different diameters. The experimental results revealed that the average heat transfer coefficient of the PCM slurry flow was about 2～2.8 times greater than that of a single phase of water.

• Proceedings of the Korea Water Resources Association Conference
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• 1982.07a
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• pp.91-98
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• 1982

The formulation of depth-averaged two-dimensional mathematical model for the analysis of tide induced circulation in a harbor by the Galerkin finite element techique is presented. In integration of the Galerkin approach in time both explicit and implicit method have been tested for one and two dimentional water bodies, and the two step Lax-Wendroff explicit method is found to be effective than the implicit in reducing computing time. The essential characteristics of the tide induced flow in Busan Harbor with two open boundaries has been foccud to be reproduceable in the numerical model and the simulated results encourage that the model can be used as a predictive tool.

• Korean Journal of Clinical Laboratory Science
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• v.43 no.3
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• pp.120-123
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• 2011

A total of 30 water samples were collected from 30 different public baths in Seoul, Korea. Contamination of public bath water by waterborne pathogens can cause disease outbreaks and contribute to increase background rates of disease. Pathogens in water was filtered by nitrocellulose membrane with $0.45{\mu}m$ pore size. The membrane filters were analyzed by both cultivation and polymerase chain reaction (PCR) amplification of partial 16S rRNA gene. Various microorganisms including 4 Escherichia coli/Shigella spp. 1 Salmonella spp. 3 Pseudomonas aeruginosa and 2 Mycobacterium spp. were identified by reverse blot hybridization assay (REBA). PCR-REBA was able to identify many bacterial genera in one assay. Our results suggest that appropriate hygiene practice and continuous monitoring is needed for reducing health risk associated with public bath houses.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.04a
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• pp.90-93
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• 2003

Sampling of waters from each stage of treatment system, SAPS (Successive Alkalinity Producing System), and spring water near the Hanchang coal mine of Kangwon. Province were carried out periodically and analyzed to evaluate the source and possible path of groundwater contamination by acid mine drainage(AMD). Chemical and sulfur isotope compositions showed that spring water was affected by seepage from mine tailings, and seepage of stonewall, a part of treatment system, was affected by both seepage from mine tailings and mine adit drainage. Through the treatment system no appreciable decrease of sulfur content was identified. And almost similar sulfur isotope compositions of water from each stage of the treatment system may suggest incomplete or very poor sulfate reduction by sulfate reducing bacteria.