• Microbiology and Biotechnology Letters
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• v.31 no.3
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• pp.250-256
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• 2003

Lactic acid bacteria with amylolytic and acid producing activities can ferment starch directly to lactic acid thereby producing a monomer for the production of biodegradable poly lactic acid (PLA). In this study, the strain producing L-lactic acid from soluble starch was isolated from Nuruk. The isolated strain was identified as Enterococcus sp. through its morphological, cultural, biochemical characteristics as well as the 16S rDNA sequence analysis, and named Enterococcus sp. JA-27. Enterococcus sp. JA-27 produced exclusively L-lactic acid from soluble starch as a carbon source. The optimal conditions for the maximum production of L-lactic acid from Enterococcus sp. JA-27 were 30 C, pH 8, 1.5 % soluble starch as a substrate and 3.5 % tryptone as a nitrogen source, 0.1 % $K_2$$HPO_4$, 0.04 % $MgSO_4$. $7H_2$O, 0.014 % $MnSO_4$$.$4$H_2O$, 0.004% $FeSO_4$$.$$7H_2$O. Batch and fed batch culture were carried out and the former was more effective. L-Lactic acid production in the optimum medium was significantly increased in a 7 L jar fermenter, where the maximum L-lactic acid concentration was 3 g/L. For the purification of lactic acid in fermented broth, two stage ionexchange column chromatographies were employed and finally identified by HPLC.

• Korean Journal of Soil Science and Fertilizer
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• v.18 no.2
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• pp.134-139
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• 1985

This study was designed to understand the relationships among the soil physical and chemical properties and to obtain the useful regression to calculate the cation exchange capacity, field capacity, wilting point moisture content and organic matter content. Fourteen soil properties were collected from 315 representative soil series in Korea. Simple and multiple regression were analyzed with the data by grouping land use, drainage class and soil depth. The multiple regression equations which can be calculated the cation exchange capacity from clay and organic matter content were found out. Cation exchange capacity of clay was 22me/100g, and that of organic matter was 103.3me/100g. Moisture retentions, both of wilting point moisture content and field capacity, were closely related to clay and organic matter content. The coefficient of clay was increased with drainage class changed more poor but the coefficient of organic matter was highest at moderately well drained soil. Organic matter content can be calculated by soil texture and pH. Organic matter content was decreased by in creasing the pH. The highly significant regressions were found between base saturation and pH.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.42 no.12
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• pp.127-134
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• 2005

Lost packet robustness is an most important quality measure for voice over IP networks(VoIP). Recovery of the lost packet from the received information is crucial to realize this robustness. So, this paper proposes the lost packet recovery method from the received information for real-time communication for CELP coder. The proposed BS-PLC (Both Side Packet Loss Concealment) based WSOLA(Waveform Shift OverLab Add) allow the lost packet to be recovered from both the 'previous' and 'next' good packet as the LP parameter and the excitation signal are respectively recovered. The burst of packet loss is modeled by Gilbert model. The proposed scheme is applied to G.729 most used in VoIP and is evaluated through the SNR(signal to noise) and the MOS(Mean Opinion Score) test. As a simulation result, The proposed scheme provide 0.3 higher in Mean Opinion Score and 2 dB higher in terms of SNR than an error concealment procedure in the decoder of G.729 at $20\%$ average packet loss rate.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.48 no.2
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• pp.123-134
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• 2022

In this study, the whitening and antioxidant effects of the extracts from Hydrangea petiolaris (H. petiolaris) leaves was confirmed, and the chemical structure was identified by separating the active ingredients. In the whitening tests using α-MSH stimulated B16F10 melanoma cells, the n-hexane (Hex) fraction inhibited the cellular melanogenesis and intracellular tyrosinase activities without causing cell toxicity. In addition, the Hex fraction reduced expression of tyrosinase and TRP-2 protein. Upon the anti-oxidative studies by DPPH and ABTS⁺ radicals, potent radical scavenging activities were observed in the ethyl acetate (EtOAc) fraction. Also, for the cellular protective effects on HaCat keratinocytes damaged by H₂O₂, the EtOAc fraction indicated protective effects against oxidative stress. Eight phytochemicals were isolated from the extract of H. petiolaris leaves; ethyl linoleate (1), ethyl linolenate (2), 1-linoleoyl glycerol (3), 1-linolenoyl glycerol (4), epi-catechin (5), afzelin (6), quercitrin (7), hyperin (8). Among the isolates, the compounds 5 - 8 showed DPPH and ABTS⁺ radical scavenging activities. The contents of quercitirin, a major isolated in this extract, determined by HPLC analysis were confirmed to be about 31.3 mg/g for the 70% ethanol extract and 169.8 mg/g for the EtOAc fraction. Based on these results, it was suggested that the extract from H. petiolaris leaves could be potentially applicable as whitening and anti-oxidative ingredients in cosmetic formulations.

• Korean Security Journal
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• no.21
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• pp.121-134
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• 2009

The purpose of present study was to examine the effects of working time on fatigue and immune function in private security. The number of private guard on which this study has been conducted in 153, who work at large companies, medium or small companies and the like as located in Seoul and kyonggi. In this study blood T-lympocyte, Natural T-Killer cell and immunoglobulin(IgG, IgA and IgM) were measured to see the level of working hours. There was significant difference in Natural T-Killer cell and immunoglobulin(IgG, IgA and IgM) and fatigue between working hours(P<0.05). in view of the results of this study, it can be thought that fatigue and immune function is more affected by working hours In summary, these results are interpreted to mean that fatigue levels and immune function (Natural T-Killer cell, and immunoglobulin) decrease due to a rise in working hours.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.28 no.5
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• pp.382-390
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• 2017

In this paper, we consider particular exposure scenarios to evaluate human effects for inductive commercial wireless charging device operating at low frequency. The coil used in this study is the A10 model in Qi standard proposed by WPC(Wireless Power Consortium), and input power is 5 W to the operating frequency of 155 kHz. In perfectly aligned condition, the max leakage magnetic field is $257.58{\mu}T$ which is obtained at the side of the device, and it is exceeded about 7.4 times of the ICNIRP 1998 reference level. The SAR is evaluated with homogeneous phantom which has electric constants of wet skin. The max value of the SAR is $134.47{\mu}W/kg$ which is obtained at the side of the device also, and it is much lower than the international guidelines. Especially, it showed higher SAR values in case of misalignment condition, so we will need to consider the misalignment condition importantly when we evaluate human effects for wireless power transfer system.

• Journal of Sensor Science and Technology
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• v.23 no.2
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• pp.134-141
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• 2014

A stoichiometric mixture of evaporating materials for $BaIn_2Se_4$ epilayers was prepared from horizontal electric furnace. To obtain the single crystal thin films, $BaIn_2Se_4$ mixed crystal was deposited on thoroughly etched semi-insulating GaAs(100) substrate by the Hot Wall Epitaxy (HWE) system. The source and substrate temperatures were $620^{\circ}C$ and $400^{\circ}C$, respectively. The crystalline structure of the epilayers was investigated by the photoluminescence and double crystal X-ray diffraction (DCXD). The carrier density and mobility of $BaIn_2Se_4$ epilayers measured from Hall effect by van der Pauw method are $8.94{\times}10^{17}cm^{-3}$ and 343 $cm^2/vs$ at 293 K, respectively. The temperature dependence of the energy band gap of the $BaIn_2Se_4$ obtained from the absorption spectra was well described by the Varshni's relation, $E_g(T)$=2.6261 eV-$(4.9825{\times}10^{-3}eV/K)T^2/(T+558 K)$. The crystal field and the spin-orbit splitting energies for the valence band of the $BaIn_2Se_4$ have been estimated to be 116 meV and 175.9 meV, respectively, by means of the photocurrent spectra and the Hopfield quasicubic model. These results indicate that the splitting of the ${\Delta}so$ definitely exists in the ${\Gamma}_5$ states of the valence band of the $BaIn_2Se_4/GaAs$ epilayer. The three photocurrent peaks observed at 10 K are ascribed to the $A_1-$, $B_1$-exciton for n = 1 and $C_{21}$-exciton peaks for n=21.

• Korean Journal of Poultry Science
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• v.12 no.2
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• pp.127-134
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• 1985

Battery trial with 240 broiler chicks of Hubbard strain was conducted for a period of 2 weeks in order to compare the anticoccidical efficacy of polyether ionophorous antibiotics ; Maduramicin ammonium, Monensin and Salinomyc in sodium. The criteria used in these anticoccidial efficacy studies were anticoccidial index, growth rate, feed efficiency, mortality, lesion score and the number of oocysts produced after artificial inoculation with 70,000 sporulated oocysts of Eimeria tenella(90%) and E.necatrix (10%) to each bird. The result obtained are summarized as follow: 1. All groups medicated anticoccidial feed additives improved body weight gain and feed efficiency. However, it was found that the group medicated with Maduramicin showed better body weight gain (352.5 and 648.8 g) and feed efficiency(1.603 and 1.680) during the first and the second week experiments, 2. The mortality rate(4.2%) and lesion scores (1.72) of Maduramicin medicated group, from artificial coccidiosis were comparatively lower than those of other two medicated groups, 3. It was also found that oocyst output (0.25 ${\times}$ 10$^4$) in Maduramicin medicated group were lower than those of other two groups. 4. Anticoccidial indexes during the first week were 177.9 in Maduramicin medica-group, 158.7 in Salinomycin medicated group, 141.6 in Monensin medicated group and 78.0 in infected, nonmedicated group as compared with 200.0 in noninfected, nonmedicated group (NNC) 5. Anticoccidial indexes during the second week were 201.1 in Maduramicin group 184.0 in infected, nonmedicated group as compared with 200.0 in noninfected, nonmedicated group (NNC).

• Radiation Oncology Journal
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• v.10 no.1
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• pp.69-76
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• 1992

To identify pretreatment prognostic factors in locally advanced carcinoma of the uterine cervix, retrospective analysis was undertaken of 154 patients treated with curative radiation therapy at Seoul National University Hospital, from March 1979 through December 1986. According to FIGO classification, eight patients were stage IIIA, 134 were stage IIIB, and 12 were stage IVA. Five year locoregional control rate was $58\%$, $51\%$, and $27\%$ in stage IIIA, IIIB, and IVA, respectively. Five year disease free survival was $57\%$, $40\%$, and $25\%$ for each stage respectively. Five year overall survival was $67\%$, $51\%$, and $33\%$ in stage IIIA, IIIB, and IVA, respectively. In univariate analysis, fewer than or equal to four of pregnancies, initial hemoglobin of lower than $10\;g\%$, and pelvic sidewall invasion on CT were associated with poor locoregional control. Number of pregnancies, initial hemoglobin level, obstructive uropathy on intavenous pyelography (IVP), pelvic lymph node (LN) status on CT, and pelvic sidewall invasion on CT were significant factors in disease free survival. In terms of overall survival, pelvic sidewall invasion on CT and bladder invasion on CT were prognostically significant. In multivariate analysis, no factor was found to affect locoregional control and pelvic LN status was a sole significant factor affecting disease free survival. in terms of overall survival, the size.

• Journal of The Korean Society of Grassland and Forage Science
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• v.35 no.2
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• pp.119-124
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• 2015

In this study, we sought to evaluate the growth characteristics and seed productivities of domestic tall fescue that were cultivated with differing combinations of drill widths and nitrogen-application rates in early spring; the examination was conducted at the National Institute of Animal Science, RDA, from 2013 to 2014. The main plots were three widths of 15 cm, 30 cm, and 45 cm, and the subplots were subject to nitrogen-application rates in early spring of 45 kg/ha, 90 kg/ha, 135 kg/ha, and 180 kg/ha. The growth and development characteristics did not vary by treatment in terms of drill width and early-spring nitrogen application. Tall fescue Purumi showed a stable seed productivity of two tons or greater when the drill width was set at 15 cm and 90 kg/ha of nitrogen was applied in early spring. The narrower the drill width, the greater the numbers of both the ears and seeds, while the length of the ear was longer when the drill width was wider. Regarding the influence of the drill width and early-spring nitrogen application on the productivity of seed-producing straw, the dry matter productivity was higher when the drill width was narrower; however, no particular trend was observed with respect to different amounts of fertilizer. The average production amount of the first round of straw after seed gathering was 6,920 kg/ha. The second round produced an average 8,134 kg/ha of dry matter.