• Computers and Concrete
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• v.15 no.1
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• pp.127-140
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• 2015

The process of chloride ingress in saturated concrete was presented by a previous study that used a mathematical model for the same as that concrete. This model is to be studied chloride ion diffusion which is considered as a chemical phenomenon and is to be represented the chloride diffusion process to be a nonlinear partial differential equation (PDE). In this paper, this nonlinear PDE is solved by the Kirchhoff transformation to render into a linear PDE. This linear PDE associated with initial and boundary conditions is also solved by the Laplace transformation to obtain an analytical solution. To verify the serviceability and reliability of this proposed method, the practical application should be supplied. The input parameters were cited from the previous study. The free chloride concentration profiles obtained by the analytical solution of mathematical model for saturated concretes after 24 and 120 hrs of exposure were compared with the previous study. The predicted results obtained from proposed method have a tendency with experimental results obtained by the previous study and trend toward numerical results approximated by finite difference technique.

• Natural Product Sciences
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• v.21 no.1
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• pp.6-13
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• 2015

Phytochemical investigation of the aerial components of Ducrosia ismaelis Asch. led to the isolation of six known compounds, psoralen (1), isopsoralen (2), cnidioside A (3), (-)-syringaresinol-O-${\beta}$-D-glucopyranoside (4), (E)-plicatin B (5), trilinolein (6). The chemical structures of these compounds were elucidated from spectroscopic data and by comparison of these data with previously published results. The antioxidant, anti-osteoporotic and cardiovascular related activities of the isolated compounds were assessed using oxygen radical absorbance capacity (ORAC), reducing capacity, tartrate-resistant acid phosphatase (TRAP), and soluble epoxide hydrolase (sEH) inhibitory activity assays. Compounds (3-5) showed potent peroxyl radical-scavenging capacities with ORAC values of $11.06{\pm}0.39$, $7.98{\pm}0.10$, and $13.99{\pm}0.06$ Trolox equivalent (TE) at concentrations of $10{\mu}M$, respectively. Only compounds 4 and 5 was able to significantly reduce $Cu^{2+}$ ions, with a reduction value of $9.06{\pm}0.32$ and $4.61{\pm}0.00{\mu}M$ Trolox Equivalent (TE) at a concentration of $10{\mu}M$. Compound 5 at $10{\mu}M$ exhibited a potent inhibitory effect on osteoclastic TRAP activity with a TRAP value of $86.05{\pm}6.55%$ of the control. Compounds 1, 3 and 5 potently inhibited sEH activity with $IC_{50}$ values of 41.6 4.9, 16.0 1.1, and 49.0 $5.7{\mu}M$, respectively.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1995.11a
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• pp.77-80
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• 1995

GaSb crystals were grown by the vertical Bridgman method. P-type GaSb crystals were grown with Ga:Sb=1:1 at % ratio without dopants and with Te, respectively. Also, GaSb:Te crystals were investigated. Lattice constants were 6.117${\AA}$ for p-type. The carrier concentration, the resistivity, and the carrier mobility measured by the van der Pauw method were p≡8 x $10^{16}$$cm^{-3}$, p≡0.20$\Omega$-cm, ${\mu}$$_{n}$≡$400\textrm{cm}^2$$V^{-1}$$sec^{-1}$ for p-type, n≡1 x $10^{17}$$cm^{-3}$, p≡0.15 $\Omega$-cm, ${\mu}$$_{n}$≡$500\textrm{cm}^2$$V^{-1}$$sec^{-1}$ for n-type at 300K. In case of treating with metal ion of $Ru^{+3}$, $Pt^{+1}$, p≡2 x $10^{17}$$cm^{-3}$, p≡0.08$\Omega$-cm, ${\mu}$$_{n}$≡420$\textrm{cm}^2$$V^{-1}$$sec^{-1}$ for p-type, n≡2.5 x $10^{17}$$cm^{-13}$, p≡0.07 $\Omega$-cm, ${\mu}$$_{n}$≡520$\textrm{cm}^2$$V^{-1}$$sec^{-1}$ for n-type were obtained.

• Analytical Science and Technology
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• v.18 no.6
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• pp.559-567
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• 2005

For the analytical method of PCDD/Fs in blood, which have been issued recently, SRM 1589a of NIST(National Institute of Standards and Technology) was used and a practical analytical method of PCDD/Fs in blood was presented through comparison of methods of Canada and Japan. The proposed method used alkali-digestion extraction for removal of the lipid effectively using two capillary columns. The limit of quantification of TeCDD/DF and PeCDD/DF was 1 pg/g-lipid, HxCDD/DF and HpCDD/DF was 2 pg/g-lipid, OCDD/DF was 4 pg/g-lipid. With consideration the range of detected concentration, calibration standards were presented as $CS_L$(0.1~1), $CS_1/2$(0.25~2.5), $CS_1$(0.5~5.0), $CS_2$(2~20), $CS_3$(10~100).

• Journal of Microbiology and Biotechnology
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• v.32 no.10
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• pp.1315-1324
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• 2022

Fermentation is an effective process for providing various beneficial effects in functional beverages. Lactic acid bacteria and yeast fermentation-based biotransformation contribute to enhancement of nutritional value and digestibility, including lactose intolerance reduction and control of infections. In this study, the probiotic fermented fruit juice (PFJ) was produced by Lactobacillus plantarum TISTR 1465, Lactobacillus salivarius TISTR 1112, and Saccharomyces boulardii CNCM I-745 while mixed fruit juice (MFJ) was used as the basic medium for microorganism growth. The potential function, the anti-salmonella activity of PFJ, was found to be effective at 250 mg/ml of MIC and 500 mg/ml of MBC. Biofilm inhibition was performed using the PFJ samples and showed at least 70% reduction in cell attachment at the MIC concentration of Salmonella Typhi DMST 22842. The antioxidant activities of PFJ were determined and the results revealed that FSB.25 exhibited 78.40 ± 0.51 mM TE/ml by FRAP assay, while FPSB.25 exhibited 3.44 ± 0.10 mM TE/ml by DPPH assay. The volatile compounds of PFJ were characterized by GC-MS, which identified alcohol, aldehyde, acid, ester, ketone, phenol, and terpene. The most abundant organic acid and alcohol detected in PFJ were acetic acid and 2-phenylethanol, and the most represented terpene was β-damascenone. The sensory attributes showed scores higher than 7 on a 9-point hedonic scale for the FPB.25, illustrating that it was well accepted by panelists. Taken together, our results showed that PFJ could meet current consumer demand regarding natural and functional, fruit-based fermented beverages.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2009.10a
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• pp.584-590
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• 2009

Since driving include compilcated actions that require a variety of abillity and cause extrme concentration or strain, divers tend to feel tired easiy. However, divers can't recognize fatigue degree by himself and accordingly the methods to measure quantitative fatigue degree exactly is quite difficult to be secured. In this study, the most efficient driving posture was suggested based on the analysis of quantitative muscular strength and fatigue degree according to posture. The driver whom we experimented included 9 commercial bus drivers. We also analyzed quantitative legs' muscular strength according te operating each pedal, left and right then we analyzed muscular strength and muscular fatigue degree according to driving pattern while driving commercial buses. And then we suggested the most efficient driving posture.

• Journal of Sensor Science and Technology
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• v.16 no.2
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• pp.91-96
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• 2007

The characteristic of tellurium thin films was studied for detecting nitrogen dioxide gas at room temperature. The film was deposited on $Al_{2}O_{3}$ substrate by using thermal evaporator. The subsequent process was heat treatment by several conditions. (temperature, flowed gases) Surface and grain boundary was investigated using SEM. The results showed that resistance of the tellurium film decreases reversibly in the presence of nitrogen dioxide. The sensitivity of this device depends on the gas concentration and detect lower concentrations less than 10 ppm.

• Korean journal of food and cookery science
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• v.16 no.6
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• pp.623-628
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• 2000

The antioxidative effect of mugwort extracts was measured by DPPH and LDL with four different solutions (70% acetone, ethanol, hot water, cold water). Mugwort extracts contained 3.2% of polyphenol, 380 RE/l00 g of vitamin A, 16.2 mg/100 g of vitamin C, and 5.1 ${\alpha}$-TE/100 g of vitamin E. DPPH revealed the effect in the order of 70% acetone, hot water, ethanol, and cold water. In particular, 70% acetone showed outstandingly stronger activity than the control group. Also, when 10 ${\mu}\ell$ was added, the effect was well noticed. But the antioxidative activity was hardly seen at 15 ${\mu}\ell$. LDL exhibited the same order of strength in proportion to mugwort＇s concentration. Against the control group, the activity of 70% acetone was 7 times, hot water and ethanol 6 times, and cold water 2 times. This result is attributable to the antioxidative increase of polyphenol and antioxidative vitamins.

• 한국신재생에너지학회:학술대회논문집
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• 2009.11a
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• pp.365-365
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• 2009

CBD 증착 방법은 저비용으로 양질의 CdS 박막을 얻을 수 있는 증착 밥법으로, 고효율의 CdTe/CdS 태양전지를 얻기에도 적당하다. CdS 박막의 증착 과정에서 수산화 암모늄 (ammonium hydroxide) 은 박막의 특성을 결정하는 주요한 요소 인자 이다. ITO가 증착된 유리기판위에 CdS 박막 증착 과정에서 동일한 조건에서 산화 암모늄 (ammonium hydroxide) 의 농도만을 조절하여서, XRD, Raman spectrometer, UV-Vis, SEM 분석 장치를 이용하여 구조 및 광학 특성의 변화를 살펴보았다.

• Korean Journal of Soil Science and Fertilizer
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• v.8 no.2
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• pp.105-111
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• 1975

Nitrogen efficiency for grain yield(E) and its relation to grain yield(Y), harvesting index(HI), percent translocation of nitrogen from straw to grain(T), nitrogen uptake amount(N), concentration in grain (GN%) or straw (SN%) and total dry matter yield (TY) among rice varieties (Oryza sativa, old and new varieties) were investigated at four nitrogen nutritional status (high and low fertilizer levels in high and low fertility fields) by simple correlation analysis. Relation between any two of above parameters or total dry matter yield (TY) and nitrogen efficiency for total dry matter yield (TE) was also investigated. 1. E is significantly and positively correlated with T, Y, HI but negatively with SN%, N, GN% and in negative trend with TY. 2. T is significantly and positively with GN% or Y, but negatively with SN%. 3. TE is significantly and positively correlated with TY but negatively with N. 4. The order of E among varieties showed consistency among different nitrogen nutritional environments. 5. From the above facts it was concluded that high yielding varieties have high nitrogen efficiency due to high percent translocation of nitrogen from straw to grain, subsequent low nitrogen concentration in straw and that translocated nitrogen in grain is greatly diluted with photosynthates. 6. Reported physiological characteristics of newly bred high yielding IR lines are well accordance with their high nitrogen efficiency and rice breeding was a selection on the basis of nitrogen efficiency. 7. It is postulated that high nitrogen efficiency varieties for yields have high nitrogen efficiency for root growth in early stage so that uptake more efficient soil nitrogen in later growth stage.