• The Korean Journal of Mycology
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• v.23 no.2 s.73
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• pp.153-160
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• 1995

As part of our search for less toxic antimicrobial agents from natural resources, the antimicrobial activity of Elfvingia applanata $(P_{ers.})\;K_{arst.}$ extract was examined alone and in combination with naringenin. EA, the aqueous extract from the carpophores of E. applanata, was lyophilized and a dark brownish powder was obtained. Antimicrobial activity of EA was tested in vitro against nineteen strains of bacteria and eleven strains of fungi by serial broth dilution method, and expressed by minimal inhibitory concentration (MIC). Among nineteen strains of bacteria tested, the antimicrobial activity of EA was the most potent against Proteus vulgaris showing MIC of 1.125 mg/ml. EA also inhibited the growth of the selected fungi at higher concentrations ranging from 7.5 mg/ml to 15.0 mg/ml. To investigate the effect of antimicrobial combinations of EA with naringenin, the fractional inhibitory concentration index (FICI) was determined by checkerboard assay for each strain. The antimicrobial combinations of EA with naringenin resulted in partial synergism against Staphylococcus aureus only, and showed additive effect in two strains including Klebsiella pneumoniae and Salmonella typhi. Antagonism was not found.

• Korean Chemical Engineering Research
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• v.43 no.6
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• pp.704-714
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• 2005

Phase separations of Poly(4-vinylphenol)(PVPh)/Ethyl Acetate and PVPh/Butyl Acetate solutions were measured using the thermal optical analysis (TOA) method. The experimental phase separation data were correlated with liquid-liquid equilibria relations based on PC-SAFT equation of state. The phase separations of these system showed the behaviors of LCST (lower critical solution temperature)-type. The measured cloud temperatures were lowered with increasing in molecular weights of polymer(PVPh), and cloud temperatures of PVPh/Ethyl Acetate solutions shifted to lower temperature regions, compared to the PVPh/Butyl Acetate solutions. Extents of cross-association between solvent molecule and polymer in the PVPh/Ethyl Acetate solutions were measured using the FT-IR spectrum analysis method, and cross-association parameters of PC-SAFT model were estimated from experimental extents of cross-association. By using the estimated cross-association parameters between PVPh and solvent molecule, binodal and spinodal curves of liquid-liquid equilibria in PVPh/Ethyl Acetate and PVPh/Butyl Acetate solutions were calculated from PC-SAFT equation of state. The calculated binodal curves of these system were shown to be well agreeable with the experimental cloud temperature curves.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.1
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• pp.61-66
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• 2010

The purpose of this experiment is to analyze the basic status of brain. Which are consist of rest, attention and concentration, of the brain by measuring the temperature of color by changing RGB color after manufacturing LED-illumination stand. Basic status (rest, attention and concentration) of experimenter were measured temperature of colors having three difference temperature like as $2,300^{\circ}K$, $4,000^{\circ}K$ and $6,000^{\circ}K$. The results was shown that experimenter feels more comfortable and relaxation by decreasing the temperature of color. For example we can see the little increase of concentration index at $4,000^{\circ}K$ condition and we can estimate that right brain can be more activated at the $4,000^{\circ}K$ condition. But we can not find out any different at the $6,000^{\circ}K$ condition. Main cause of no difference from the color temperature was the similarity of color temperature under the general fluorescent lamp. And interface temperature of radiant heat design results LED and PCB was approximately 80 degrees to COMSOL Multiphysics, and changed until approximately 50 degrees until a floor plane of PCB, and verification as arranged chip LED to metal PCB, and it was possible, and a near radiant heat design was confirmed to an approximate value of, as a result, acid manufacture.

• The Journal of the Korea Contents Association
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• v.12 no.9
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• pp.500-511
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• 2012

Recently, use frequency for traffic information which provides shortest paths and traffic condition is increasing. Specially, in the survey, it is shown that users prefer internet portal sites which can be used the most easily among traffic information media. But, there are not many verification systems for traffic information contents of internet portal sites which collect and provide information than traffic information contents which are provided by public service. The purpose of this study is to investigate real accuracy and accuracy felt by users about information provided by portal sites. Therefore, in this research we verified accuracy of information by portal site with real field data and investigate real usage about contents and experienced accuracy by users through survey. Also, users' expectation and satisfaction were surveyed and the contents to be improved were selected by using IPA technique. By the result of accuracy verification by field data using portable DSRC(Dedicated Short Range Communication) devices, it is shown that average error was 14~32% and sometimes very high rate. Also, it is shown that 28.3 % of total respondents prefers the information by portal sites and 50 % of total respondents felt that contents of traffic information by portal sites are not accurate. Real-time traffic condition was selected as the most inaccurate one among all contents of traffic information and it was analyzed that intensive efforts for improving information about real-time traffic condition are needed.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.37 no.9
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• pp.15-22
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• 2000

The effects of carrier transport and input power on the extinction ratio was theoretically analyzed in a 1.55${\mu}m$ InGaAsP/InGaAsP multiple-quantum-well(MQW) electroabsorption(EA) modulator. Poisson's equation, current continuity equations for electrons and holes, and optical field distribution were self-consistently solved by considering electric field dependent absorption coefficients. The field screening effect due to the carrier accumulation in heterointerface and the space-charge region occurred more seriously at the input side of modulator as input optical intensity increased. It was revealed that extinction ratio could be steeply degraded for modulator with the length of 200${\mu}m$ when an input power exceeds 10mW. A degradation of extinction ratio due to the field screening effect would be more significantly at high-performance devices such as a 1.55${\mu}m$DFB-LD/EA-modulator integrated source where optical coupling efficiency is almost complete or a very high-speed modulator with its length as short as a few tens ${\mu}m$.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.3A
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• pp.368-376
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• 2006

This paper describes a Fcore_GenSim(Parameterized FFT Core Generation & Simulation Program), which can be used as an essential If(Intellectual Property) in various OFDM modem designs. The Fcore_Gensim is composed of two parts, a parameterized core generator(PFFT_CoreGen) that generates Verilog-HDL models of FFT cores, and a fixed-point FFT simulator(FXP_FFTSim) which can be used to estimate the SQNR performance of the generated cores. The parameters that can be specified for core generation are FFT length in the range of 64 ~2048-point and word-lengths of input/output/internal/twiddle data in the range of 8-b "24-b with 2-b step. Total 43,659 FFT cores can be generated by Fcore_Gensim. In addition, CBFP(Convergent Block Floating Point) scaling can be optionally specified. To achieve an optimized hardware and SQNR performance of the generated core, a hybrid structure of R2SDF and R2SDC stages and a hybrid algorithm of radix-2, radix-2/4, radix-2/4/8 are adopted according to FFT length and CBFP scaling.

• Journal of the Korean Institute of Landscape Architecture
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• v.14 no.2
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• pp.69-80
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• 1986

In order to analyse the color preference quantitatively, specially with reference to the subjects in the age of twenties, 100 subjects(M=50, F=50) that unconsidered other factors were adopted and responded to 4 items of the questionaire. The item no. 1 was to investigate the most prefered color on the white background, no. 2 was to most preferred stimulation -level of lightness in the same hues, no. 3 was to most prefered color on 5 different backgrounds -grey, blue, pink, yellow, and yellow green-, and no. 4 was same as no. 3 but with different color-arrangement Materials for item 1 and 3 were made with transparent acryl-boards(30cm$\times$30cm), on which 16 color chips arranged on circle, for item 4 on lattice, and for item 2 with 16 white boards(8cm$\times$21cm), on which 7 color chips of different lightness-level arranged. Reflectance(Y) and color coordinate(x, y) of all color chips measured with color difference meter were transfered into wavelength(nm), exitation purity(%), and Munsell's value. The results may be summarized as follows: 1) Most prefered color was bluish green with wave1ength about 500nm. As increasing of exitation purity of color, more prefered. 2) When there were 7 different levels of lightness in the same hues, the relationship between the number of preference and the stimulation was inverted U-shaped. 3) With changing the background -color, the prefered colors were contrasting when backgrounds were low or high intensity-stimulation and familiar colors when backgrounds were medium intensity.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.6
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• pp.4011-4020
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• 2015

The purpose of this study was to determine the self efficacy, body image and family support affect on postpartum depression in early postpartum mothers. The data was collected 306 mothers on the first week after delivery from one hospital located in B city. The instruments were a survey of general characteristics, obstetrical characteristics, the Edinburgh Postnatal Depression Scale(EPDS), self-efficacy, body image and family support. Data was analysed using descriptive statistics, Pearson correlation coefficients, and stepwise multiple regression. The results revealed that the average item score of the EPDS was 6.09. The significant predictors of postpartum depression were body image, emotional state in pregnancy, and family support. These variables had a 38.4% explainability. The results indicate that the postpartum mothers should be screened for postpartum depression early in the postpartum period and it's necessary to implement nursing intervention focused on to enhance the body image and family support, especially the weak emotional state mothers in pregnancy.

• Journal of Life Science
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• v.15 no.6 s.73
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• pp.884-888
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• 2005

An agar-degrading bacterium was isolated from north-eastern sea of Jeju island and cultured in marine agar 2216 media. Biochemical and morphologicl characteristics and 165 rRNA gene revealed that isolated strain was member of Agarivorans genus, and named Agarivorans sp. JA-1. Agarase was produced as growth-related and expressed regardless of agar presence. Optimal pH was 8 at 50 mM Clycine-NaOH buffer, and activity was maximum at $40^{\circ}C$E Enzymatic activity was maintained over $80\%$ at $60^{\circ}C$t and $70\%$ at $80^{\circ}C$ which is thermotolerant. Hence isolated novel Agarivorans sp. JA-1 strain and its beta-agarase could be used for the production of functional oligosaccharide from agar in solution state.

• Journal of Chitin and Chitosan
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• v.23 no.4
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• pp.213-219
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• 2018

The purpose of this study was to investigate the quality characteristics and antioxidant activity of black rice muffins prepared with various concentrations of chito-oligosaccharide(0, 0.5, 1.0, 1.5, 2.0%). The the weight of the groups with chito-oligosaccharide was higher than that of the control group, but the height, volume, and specific volume of the groups with chito-oligosaccharide were lower than those of the control group. The moisture contents increased with the addition of chito-oligosaccharide. The pH decreased significantly with the addition of chito-oligosaccharide. The L value of Hunter's color decreased, but the a and b value increased significantly with the addition of chito-oligosaccharide. The muffin without the chito-oligosaccharide was the highest hardness. The textural properties revealed the cohesiveness, chewiness, and brittleness of groups with chito-oligosaccharide increased significantly with the addition of chito-oligosaccharide. Antioxidant activities of muffins increased as the amount of chito-oligosaccharide increased.