• Journal of Magnetics
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• v.16 no.2
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• pp.186-191
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• 2011

[ $YBa_2C_3O_{7-x}$ ]films were fabricated on a $SrTiO_3$ (100) substrate using a trimethylaceate propionic acid (TMAP)-based MOD process by controlling the precursor solution viscosity, firing temperature, and by using various coatings. The viscosity of the precursor solution was controlled by the addition of Xylenes. The films were heat treated with different temperatures from 750 to $800^{\circ}C$. c-axis oriented films were obtained. After adding 9 ml of Xylene into the precursor solution, the $T_c$ of the YBCO film, which was coated 2 times and heat treated at $800^{\circ}C$, was 86 K and the measured $J_c$ was above 2.5 MA/$cm^2$ at 77 K in a zero-field.

• Journal of Microbiology
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• v.43 no.4
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• pp.370-374
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• 2005

Bacteriocin ST311LD is approximately 2.3 kDa in size. Low levels of bacteriocin activity were recorded in BHI and M17 broth (800 AU/ml) and in $10\%$ (w/v) soy milk (3,200 AU/ml). No bacteriocin pro-duction was recorded in $10\%$ (w/v) molasses, despite good growth. Optimal levels (12,800 AU/ml) were detected in MRS broth which had been supplemented with tryptone (20.0 g/l), saccharose (5.0 or 10.0 g/l) or vitamin C (1 ppm). Increased potassium levels did not result in higher levels of activity, and glycerol (1.0 g/l) inhibited the production of bacteriocin ST311LD.

• International Journal of Precision Engineering and Manufacturing
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• v.6 no.4
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• pp.55-59
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• 2005

This paper presents a feasibility study whether Shida's constitutive equation being widely used for plain carbon steel in steel manufacturing industry can be extended to alloy steels with a due carbon equivalent model. T,he constitutive relation of the alloy steels (SAE9254, AISI52100 and AISI4140) is measured using hot deformation simulator (GLEEBLE 3500C) at high temperatures ($800^{\circ}C{\~}1000^{\circ}C$) within strain rates of $0.05{\~}40\;s^{-1}$. It has been found the predicted flow stress behavior (constitutive relation) of AISI52100 steel is in agreement with the measured one. On the other hand, the measured flow stress behavior of SAE9254 and AISI4140 steel partly concords with the predicted one when material experiences relatively high strain rate ($10{\~}40\;s^{-1}$) deformation at low temperature ($800^{\circ}C$). It can be deduced that, for AISI52100 steel, Shida's equation with the carbon equivalent model can be applicable directly to the roughing and intermediate finishing stand in hot rolling process for calculating the roll force and torque.

• Bulletin of the Korean Chemical Society
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• v.6 no.1
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• pp.11-15
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• 1985

Electrical conductivites of polycrystalline yttrium sesquioxides containing 1.6 and 3.2 mol % of holmium sesquioxdes have been measured from 650 to $1050^{\circ}C$ under oxygen partial pressures of $1{\times}10^{-5}$ to $2{\times}10^{-1}$ atm. Plots of log conductivity vs. 1/T at constant oxygen partial pressures are found to be linear away from the two inflection points. The low- and high-temperature dependences of conductivity show different defect structures of yttrium sesquioxide. The plots of log conductivity vs. log $PO_2$ are found to be linear at $PO_{2'}$s of $10^{-5}$ to $10^{-1} atm. The electrical conductivity dependences on $PO_2$ are found to be $1}5.3$ at $950-1050^{\circ}C$, $\frac{6}{1}$ at $800-950^{\circ}C$ and ($\frac{6.2}{1}$) - ($\frac{6.5}{1}$) at $650-800^{\circ}C$, respectively. The defect structures and conduction mechanisms have been suggested.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2004.05b
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• pp.800-803
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• 2004

This paper describes the design and implementation of the T=1 protocol based on lava Card. The T=1 protocol implemented in this paper complies with ISO/IEC 7816 standard. Also, JCOS(Java Card Operating Systems) including the contactless card protocol conforms to Java Card 2.2.1 specification and is running on 32-bit ARM7/TDMI processor. The protocol stack proposed and implemented in this paper is easy to maintenance of protocol independently. To verify the T=1 protocol implemented in this paper we tested the T=1 protocol scenarios defined in ISO/IEC 7816-3 Annex A. And we tested using USIM(Universal Subscriber Identity Module) cards, which include the implemented T=1 protocol. The T=1 protocol was tested and passed all against the specification 3GPP TS 31.122, which was the Conformance Test Specification for USIM cards including the test suites of both transmission protocols.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.20 no.10
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• pp.1050-1060
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• 2009

In this paper, a X-Band T/R-module for SAR(Synthetic Aperture Radar) systems based on active phased array antennas is designed and fabricated. The T/R modules have a and width of more than 800 MHz centered at X-Band and support dual, switched polarizations. The output power of the module is 7 watts over a wide bandwidth. The noise figure is as low as 3.9 dB. Phase and amplitude are controlled by a 6-bit phase shifter and a 6-bit digital attenuator, respectively. Further the fabricated T/R module has est and calibration port with directional coupler and power divider. Highly integrated T/R module is achieved by using LTCC(Low Temperature Co-fired Ceramic) multiple layer substrate. RMS gain error is less than 0.8 dB max. in Rx mode, and RMS phase error is less than $4^{\circ}$ max. in Rx/Tx phase under all operating frequency band, or the T/R module meet the required electrical performance m test. This structure an be applied to active phase array SAR Antennas.

• Journal of the Korean Society for Nondestructive Testing
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• v.13 no.2
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• pp.20-30
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• 1993

Electric Speckle Pattern Interferometry (ESPI) using a CW-laser, a video system and an image processor was applied to the thermal coefficient measurements on free thermal expansions at high temperatures : ESPI provides the distribution of in-plane displacement resolved in a preselected direction. ESPI retains the merits of little or no surface preparation, no contact with the surface and the real-time presentation of interference fringes. Appling ESPI at high temperatures, several problem which caused the reduction of fringe visibility were encountered. The problem on the turbulence in the hot air surrounding high temperature objects will be solved by using a vacuum chamber. The background radiations from the objects were suppressed considerably by an interference filter. The problem on the oxidation of the object surface could't be solved. The interference fringe, whose spacings were calculated by FFT to avoid human error, were observable up to $800^{\circ}C$. The results measured by ESPI were nearly equal to the data which have already been published, up to about $800^{\circ}C$.

• Fire Science and Engineering
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• v.15 no.3
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• pp.7-13
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• 2001

In this paper, we had analyzed comsbustion gases according to pyrolysis $600^{\circ}c$, $800^{\circ}c$ and $1000^{\circ}c$ for polymeric material using a GASTEC colorimetric gas detector tube in order to combustion gases toxicity evaluation for flame retardant untreated ply wood, flame retardant treated ply wood, flexible polyvinyl chloride and flexible polyurethane foam of polymeric material. As a result, comsbustion gases producted from small specimens of polymeric material had reached fatal to man at a 30 minute exposure time that had possesed toxicity index. Toxicity index at pyrolysis $800^{\circ}c$ of flexible polyvinyl chloride was 31.74. Flexible polyvinyl chloride was the highest toxicity index of flame retardant untreated ply wood, flame retardant treated ply wood, flexible polyvinyl chloride and flexible polyurethane foam. The comsbustion gases producted commonly no concern with pyrolysis temperature had analyzed carbon dioxide($CO_2$) and carbon monoxide(CO). Toxicity index had investigated differently according to pyrolysis temperature even a similar materal.

• Korean Journal of Food Science and Technology
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• v.3 no.1
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• pp.15-18
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• 1971

The Korean rice of Paldal variety was milled, in March, 1969, into brown rice and 92% polished one and each 1.5kg sample was packed in the kraft paper bags. With Co-60 gamma-irradiation, the samples were treated in the various ranges of 500, 800 and 1,000 Krad, and then they were stored at the room temperature. The changes of the contents of free amino acids in the samples were determined by the amino acid autoanalyzer (Yanagimoto, Japan, LC-type). The results obtained in June and October of the year were as follows. 1) In the disinfecting irradiation of rice by the higher doses of 500, 800 and 1,000 Krad, there wasn't any particular distinction between the control lot and irradiated lot in respect to the free amino acid contents. 2) The contents of free amino acids in rice during storage had the decreasing tendencies, and especially prominent in case of glutamic acid.

• Journal of the Korean Institute of Landscape Architecture
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• v.30 no.2
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• pp.95-104
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• 2002

This study was carried out to investigate the effects of pyroligneous acid on turfgrass growth and to propose usage for sustainable management on Korean golf course green. Each plot was treated with 0, 300, 500, and 800 acid to water solution. On all the plots, turfgrass growth increment and visual quality were measured at fried times. The data were subjected to paired samples t-test and corelation analysis. The summarized results are as follows; 1) Leaf growth increment, density, and root spread depth of turfgrass treated with 1: 500 and 1: 800 diluted pyroligneous acid were significantly superior to the control. Particularly, 1: 500 diluted solution was superior to the others. 2) Color, texture, and uniformity of turfgrass treated with 1: 500 and 1: 800 diluted pyroligneous acid were significantly superior to the control. Especially, 1: 500 diluted solution tended to be superior to the others. 3) There were no symptoms of disease in all plots treated with the diluted pyroligneous acid. 1 500 and 1: 800 diluted pyroligneous acid were not thought to trigger or promote disease. 4) Before and after investigating the effect of pyroligneous acid on turfgrass growth ,the soils were analyzed. In all treatments, the chemical properties of the soils did not change noticeably. The chemical properties of the soils might be not changed by the diluted pyroligneous acid treatments. 5) Considering the results mentioned above, 1: 500 diluted pyroligneous acid was the most effective. Though pyroligneous acid is an organic fertilizer and contains only a little nitrogen and phosphorus, 1: 500 diluted pyroligneous acid promoted turfgrass growth effectively. Thus this use might lead to a reduction in the amount of fertilizers used and result in ecologically responsive management of Korean golf courses.