• Journal of the Korean Society for Railway
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• v.16 no.5
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• pp.358-364
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• 2013

In the second part of the paper, a design strategy for an apartment complex constructed at a railway depot is proposed for vibration reduction purposes. Various design parameters such as the vehicle operating speeds, artificial land behavior, housing support structure, and apartment sub-structures are individually examined to reduce the transmission of vibrations through building structures. Building construction on an artificial land should be subjected to regulations that require the application of a vibration reduction scheme based on the mechanics that govern the vibration transmission phenomena. The implementation of these parameters at an early design stage will provide a quiet living environment for residents who may be exposed to excessive noise and vibration.

• Clean Technology
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• v.6 no.1
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• pp.39-49
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• 2000

Ultra Rapid Coagulation (URC) can dramatically remove pollutants loaded in wastewater by adding weighted coagulation additives (WCA) and recycling sludge into the coagulation basin to increase settling velocity and surface adsorption ability of floc. Also settling chamber together with lamella plates offers the high rate settling velocity, which can economically treat a considerable amount of pollutants like as combined sewage overflow (CSO) during the heavy rainfall and reduce the pollutants load into the receiving water for securing water source. It was estimated optimal configuration of settling chamber by using fluent model and the possibilities of reusing the sludge generated in this system.

• Journal of IKEEE
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• v.13 no.4
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• pp.57-62
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• 2009

In this paper, to implement PCS (Physical Coding Sublayer) of 10GBASE-R type, we present 2 stage pipeline 64b/66b Encoder/Decoder which operates at 156.25MHz standard specification and designed to minimize clock latency as possible as we can. The proposed circuit was designed based on Verilog hardware description language and measured for functional verification on VertexII-1000fg456 chip of Xilinx Inc.. Total equivalent gate count is 47,303 and estimated power consumption is 351mW at Vcc 3.3V.

• 한국신재생에너지학회:학술대회논문집
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• 2008.05a
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• pp.568-571
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• 2008

A novel self-humidifying composite membrane for the proton exchange membrane fuel cell (PEMFC) at low humidity condition was developed. The Pt/$TiO_2$ catalyst particles were synthesized via supercritical impregnation methods. Pt precursor was dissolved in supercritical carbon dioxide and impregnated onto $TiO_2$ particles. Pt precursors were platinum(II) acetylacetonate, Dimethyl(1,5-cyclooctadiene) platinum(II) and we controlled the ratio of Pt to $TiO_2$. The impregnated Pt precursor was converted to $TiO_2$ supported Pt nanoparticle under various reducing conditions. Pt/$TiO_2$ catalyst particles were dispersed uniformly into the Nafion solution, and then Pt/$TiO_2$/Nafion composite membrane was prepared using solution-cast method. The self-humidifying composite membrane could minimize membrane conductivity loss under dry conditions due to the presence of catalyst and hydrophilic Pt/$TiO_2$ particles. To optimize the performance of MEA, amount of ionomer loading was controlled. And mixed catalysts were used. The cell performance of MEA was obviously improved under dry conditions at $65^{\circ}C$.

• Journal of Veterinary Clinics
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• v.17 no.1
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• pp.187-193
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• 2000

Fifteen adult Korea Jin-do dogs were studied by echocardiography to obtain the basic data of the imaging planes and normal references ranges to the aorta and pulmonary artery internal dimension. Measurements of aortic root internal dimension(AOID) and right pulmonary artery internal dimension (RPAID) were made at modified pulmonary arteries level short-axis view and left ventricular outflow tract long-axis view. The aortic root internal dimension and right pulmonary artery internal dimension at modified pulmonary arteries level short-axis view were 18.7$\pm$1.3mm (mean$\pm$SD) and 10.1$\pm$0.8mm, respectively. And RPAID/AOID was 0.5$\pm$0.1mm. The aortic root internal dimension and right pulmonary artery internal dimension at left ventricular outflow tract long-axis view were 19.3$\pm$1.6 mm and 10.7$\pm$1.3mm, respectively. And RPAID/AOID was 0.5$\pm$0.1mm. These results indicate that modified pulmonary arteries level short-axis view is useful planes to examine the aortic root and pulmonary arteries, and aortic root internal dimension is significantly higher(40~50%)than the right pulmonary artery internal dimension. Therefore measurements of aortic root internal and right pulmonary artery internal dimension can be used for monitoring dilation of pulmonary artery.

• Textile Coloration and Finishing
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• v.6 no.2
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• pp.47-54
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• 1994

Cotton fiber, NaOH-mercerized cotton fiber, cotton fabric, and NaOH-mercerized cotton fabric have been treated by liquid ammonia at -33.4$^{\circ}C$. The fine structures, bending properties, tensile strengthes, shrinkages for laundering, and wrinkle recoveries were studied. The treatment of cottons with liquid ammonia brought about the transition of crystal lattice ; transforming cellulose I crystal of original cotton to cellulose I and III crystal, and cellulose II crystal of mercerized cotton to cellulose II and III crystals. The degree of crystallinities were decreased in the order of liquid ammonia>NaOH/liquid ammonia>NaOH-treated cotton. However moisture regain and water absorbency for liquid ammonia-treated cotton were lower than that of NaOH-treated cotton because of a difference in swelling actions of the agents. It seems caused by intermicrofibrillar pores produced in swelling processes. The bending rigidity and bending hysteresis were decreased remarkly by liquid ammonia treatment. Therefore softness and dimensional stability were improved. The liquid amminia and NaOH/liquid ammonia-treated cottons moreover show excellent properties in tensile strength, anti-shrinkage for laundering, and wrinkle recovery.

• Textile Coloration and Finishing
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• v.17 no.3 s.82
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• pp.8-15
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• 2005

Cationic dyeable polyester(CDP) fabric was annealed at varying temperatures range from $120^{\circ}C$ to $220^{\circ}C$ for 1, 3, and 5 min under tension. Dyeing rates of CDP fabrics were measured with cationic and disperse dyes at $100^{\circ}C$ and $120^{\circ}C$ in water system. Also X-ray diffraction pattern, DSC thermograms and dyeability of fabric with cationic and disperse dyes were investigated. The intensities of X-ray diffraction peaks of annealed fabric were increased with increasing in annealed temperature, and peak became sharp with heat setting temperature. The apparent color depth (K/S) of CDP fabric initially decreased with increase of heat-setting temperature up to $160\~180^{\circ}C$ and then increased at higher temperature. The shearing modulus(G) and surface roughness were increased with annealing temperature.

• Journal of The Korean Society of Grassland and Forage Science
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• v.16 no.1
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• pp.17-26
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• 1996

This experiment was carried out to investigate the effects of endophyte staWendophyte-free and -infect) and cutting frequency(3, 4, 5 and 6 timeslyear) on the forage quality of tall fescue(Festuca crnrtzdit~crcerr Schreb.) at the Experimental Field of Grassland and Forage Crops Division. National Livestock Research Institute, Suweon, from 1993 to 1994. 'Ihe results obtained are summarized as follows: CP content of tall fexue was increased with endophyte-free and cutting frequency for two varieties. Crude protein yield(CPY) of tall fescue in 1993 was increased with endophyte-free and cutting frequency for two varieties(P<0.05). In 1994, however. CPY of endophyte-free tall fescue was slightly lower than that of endophyte-infected tall fescue and the higher CPY was observed when tall fescue was harvested 6 times per year. NDF content of tall fescue was not different between endophyte-infected and -free. NDF was decreased with cutting frequency for two varieties in 1993, however. it was not influenced by the endophyte and cutting frequency in 1994. ADF content of tall fescue was not different between endophyte-infected and -free. and it was decreased with cutting frequency for two varieties. IVDMD was not influenced by endophyte, however, it was increased with cutting frequency for two varieties. Based on the results of this experiment, it is suggested that a slight increase in forage quality could be obtained from endophyte-free tall fescue and the quality was increased with frequent cutting.

• 한국지구물리탐사학회:학술대회논문집
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• 2005.05a
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• pp.123-127
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• 2005

Surface refraction and crosswell seismic survey conducted as a part of geoscientific studies applied in an area of ground water reservoir shows that, 1) the average velocity with respect to depth is about 250 m/s for the surface layer (<4m), 2,500 m/s for the weathered formation, and greater than 3,500 m/s for the bed rocks, 2) the depth to the bedrock derived from the seismic studies and the sonic log (17m) is somewhat different from the depth obtained from the core study (25m).

• Membrane Journal
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• v.5 no.3
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• pp.109-118
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• 1995

In this study, cell resistivity and membrane resistivity were measured in Fe-Cr redox-fiow battery system using commercial ion-exchange membranes. Cell resistivity and membrane resistivity at charging periods are higher than at discharging periods. And at the same membrane the resistivity were increased with increasing SOC. The resistivity of hydrocarbon type Seiemion CMV membrane was smaller than perfluoro type Nafion 117 and Nafion 551. The cell resistivity and membrne resistivity of CMV membrane at 0 % SOC was $12.864\Omega \textrm{cm}^2$ and $8.751\Omega \textrm{cm}^2$, respectively.