• Korean Journal of Soil Science and Fertilizer
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• v.32 no.1
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• pp.57-61
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• 1999

This study measured the soaking effects of two brassinosteroids(BRs), homobrassinolide(hBR : 225, 23S-homobrassinolide) and epibrassinolide(epiBR : 22R, 23R. 24R-$2{\alpha}$, $3{\alpha}$, 22, 23-Tetrahydroxy-B-homo-7-oxa-$5{\alpha}$-ergostan-6-one) on the germination of two rice cultivars, 'Milyang 23' and 'Naepungbyeo' exposed to simulated acid rain(SAR). The results suggested that promoting effect of two BRs on alleviating damage to SAR would be attributed to the promotion of plant growth, root elongation, and particularly germination rate of both cultivars. Eight organic acids were determined by HPLC. Succinic acid acetic acid in 'Milyang 23' under SAR were highest among eight organic acids.

• Journal of the Korean Chemical Society
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• v.44 no.1
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• pp.37-44
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• 2000

In order to develope bioactive substances, dried fmit body of Daedalea dickinsii collected from Taeback mountain was extracted with ethanol, The compounds 1 and 2 were purified by solvent extraction, silica gel column chromatography and recrystallization from the ethanol extracts. Melting point, molecular weight and molar extinction coefficient of the compound 1 were estimated to be $167{\sim}168^{\circ}C$, 572 and 5,040 at 208 nm. The structure of this compound 1 has been elucidated to be 24S, 25S, $3{\alpha}-carboxyacetylquercinic$ acid using spectroscopic properties. This compound showed antibiotic activities against fungi, yeasts and bacteria and it also showed anticancer activity $IC_{50}=64.5\;{\mu}M$) against Korean stomach cancer cell. Melting point, molecular weight and molar extinction coefficient of the compound 2 were estimated to be $233{\sim}235^<\circ}$, 572 and 5,080 at 208 nm. The structure of this compound was elucidated to be 24S, 25R, $3{\alpha}-carboxyacetylquercinic$ acid. The compound 2 showed different antibiotic activities with the compound 1.

• Environmental and Resource Economics Review
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• v.13 no.1
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• pp.1-32
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• 2004

Environmental Performance Index(EPI) has shown some limitation. Since it has lack of analysis for the relation between environmental performance and business performance, and public information. Therefore it could not provide valuable information for the shareholders to decide for the investment. In this paper by using Analystic Hierarchy Process (AHP), EPI was calculated giving some weighted scale for each environmental items. Improvement of pollution treatment, general management data such as EMS system, and environmental improvement for the products and process were the main three items when decision makers in bankings are considering the investment for a company. In empirical case, companies which has Environmental-Friendly Coorperation Award from MOE and ISO 14001 certification had shown strong relation between business performance and environmental performance.

• Journal of the Korean Applied Science and Technology
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• v.11 no.1
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• pp.7-16
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• 1994

Some seeds of the Rutaceae family, Zanthoxylum piperitum, Z. schinifolium officinalis, Poncirus trifoliata, Citrus unshin, were investigated to clarify their antioxidative components. Finely powdered samples were extracted by hexane, followed by dichioromethane and then 70% methanol in a hot bath. Its unsaponifiables containing X-and Y-tocopherol with trace amount of ${\beta}-and$\;{\delta}-tocopherol$. also showed comparatively weak activity, although the hexane fraction itself had no significant antioxidative effect on lard. Levels of total tocopherols in the samples averages 42. 24-154. 11 mg/lOOg total extractives. The dichloromethane-and 70% methanol extractives showed strong antioxidative activity, from which antioxidative substances were purified with benzene-acetone(6:5, V/V) on a silica gel column, and with a solvent mixture of acetonitrile-methanol-$H_2O$(40:40:20, V/V/V) on a Sep-Pak $C_{18}$ hydrolyzed by 5% KOH-ethanol. The recovered unsaponifiables were, then, separated on a column of high performance liquid chromatography. The unsaponifiables produced by hydrolysis of the isolates from dichloromethane extractives has epi-catechin(40.0-57.1%) and (+)-catechin<$l9.1{\sim}24.4%$ to total phenolic substances, on area base) as major component, accompanied by chlorogenic acid, gallic acid(?), trans-p-coumaric acid and tralls-p-ferulic acid including some unknown components, and those derived from 70% methanol extractives also comprise (+)-catechin($31.3{\sim}39.6%$ to total components, on area base), epi-catechin($2O.2{\sim}36.4%$), trans-p-cournaric acid(8.4-15.3%) and trans-p-ferulic acid($7.7{\sim}14.1%$) as predominant component with some minor coponents, but the fraction supposed to be gallic acid(?) is not present. The antioxidative activities of the phenolic components isolated in this work were in order of epi-catechin>catechin>chlorogenic acid>trans-p-ferluic acid>trans-p-coumaric acid.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.21 no.1
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• pp.223-228
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• 2017

In this paper, we are proposing an optimal design of wideband pulsed type gamma-ray sensors. These sensors were manufactured based on the design results and after word electrical properties were analyzed. The sensor input parameters were derived on the basis of pulsed gamma-ray spectrum and time-dependent energy rate, and the output current which were derived on the basis of the sensor sensitivity control circuit. Pulsed gamma-ray sensors were designed using the TCAD simulators. The design results show that the optimal Epi layer thickness is 45um with the applied voltage 3.3V and the diameter is 2.0mm. The doping concentrations are as follows : N-type is an Arsenic as $1{\times}10^{19}/cm^3$, P-type is a Boron as $1{\times}10^{19}/cm^3$ and Epi layer is Phosphorus as $3.4{\times}10^{12}/cm^3$. The fabricated sensor was a leakage current, 12pA at voltage -3.3V and fully depleted mode at voltage -5V. A test result of pulsed radiation shows that the sensor gives out the optimal photocurrent.

• Toxicological Research
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• v.32 no.4
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• pp.311-316
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• 2016

Effects of nanoparticles (NPs) on skin corrosion and irritation using three-dimensional human skin models were investigated based on the test guidelines of Organization for Economic Co-operation and Development (OECD TG431 and TG439). EpiDerm$^{TM}$ skin was incubated with NPs including those harboring iron (FeNPs), aluminum oxide (AlNPs), titanium oxide (TNPs), and silver (AgNPs) for a defined time according to the test guidelines. Cell viabilities of EpiDerm$^{TM}$ skins were measured by the 3-(4, 5-dimethylthiazol-2-yl)-2.5-diphenyltetrazolium bromide based method. FeNPs, AlNPs, TNPs, and AgNPs were non-corrosive because the viability was more than 50% after 3 min exposure and more than 15% after 60 min exposure, which are the non-corrosive criteria. All NPs were also non-irritants, based on viability exceeding 50% after 60 min exposure and 42 hr post-incubation. Release of interleukin 1-alpha and histopathological analysis supported the cell viability results. These findings suggest that FeNPs, AlNPs, TNPs, and AgNPs are 'non-corrosive' and 'non-irritant' to human skin by a globally harmonized classification system.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.04b
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• pp.35-36
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• 2009

In this work, we demonstrate 800V 4H-SiC power DMOSFETs with several structural alterations to obtain a low threshold voltage ($V_{TH}$) and a high figure of merit ($V_B^2/R_{SP,ON}$). To optimize the device performance, we consider four design parameters; (a) the doping concentration ($N_{CSL}$) of current spreading layer (CSL) beneath the p-base region, (b) the thickness of p-base ($t_{BASE}$), (c) the doping concentration ($N_J$) and width ($W_J$) of a JFET region, (d) the doping concentration ($N_{EPI}$) and thickness ($t_{EPI}$) of epi-layer. These parameters are optimized using 2D numerical simulation and the 4H-SiC DMOSFET structure results in a threshold voltage ($V_{TH}$) below ~3.8V, and high figure of merit ($V_B^2/R_{SP,ON}$>${\sim}200MW/cm^2$) for a power MOSFET in $V_B$-800V range.

• The Korean Journal of Pain
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• v.10 no.2
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• pp.196-202
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• 1997

Background: Various pain treatments have been administered to relieve patients suffering from postoperative pain. Among these, epidural or intravenous opiate administration is by far the most widly applied treatment in recent times. However it was our objective to device a more effective and safe means of postoperative analgesia. Methods: We studied 110 healthy pregnant women scheduled for delivery by elective cesarean section. EPI(epidural)-group is administered morphine 1.5 mg and 0.25% bupivacaine 8 ml as bolus dose, then, a mixture of morphine 6 mg and 0.125% bupivacaine 95 ml as continuous dose via epidural route. IV(intravenous)-group is administered nalbuphine 6~7 mg as bolus dose and nalbuphine 60~70 mg with 0.9% normal saline 90 ml as continuous dose via intravenous route, at the rate of 2 ml/hr for 2 days. We compared the analgesic efficacy and side effects of these two groups using VAS pain score and time duration of constant pain level. Results: VAS pain score was similar between the two groups, but pain duration was significantly shorter in EPI-group. Incidence of pruritus was significantly lower with the IV-group, of nausea and vomiting were similar for both groups, no respiratory depression for either groups. Conclusions: Although the EPI-group had better analgesic efficacy, the IV-group had lower incidence of side effects, and simplicity and safety methods of operation. Therefore, We propose further research and consideration of administering the kinds and doses of those medications prescribe to the IV group in conjunction with other drugs for safer and better efficacy of postoperative analgesia.

• Journal of Veterinary Clinics
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• v.25 no.5
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• pp.317-323
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• 2008

Canine trypsin-like immunoreactivity (cTLI), which is a mirror of the concentration of trypsin and trypsinogen, is a pancreas-specific enzyme and a suitable marker for canine pancreatitis and especially exocrine pancreatic insufficiency (EPI). To develop the immunochromatographic test kit, monoclonal antibodies that recognize cTLI were prepared. Anionic trypsin, cationic trypsin, and chymotrypsin from canine pancreas were successfully purified to homogeneity, using ammonium sulfate fractionation and benzamidine-affinity chromatography. The purification fold for anionic trypsin was 108 times when compared with that of the homogenation of pancreas. The molecular weights by SDS-PAGE analysis were approximately 23 kDa for chymotrypsin and approximately 20 kDa for cationic trypsin and anionic trypsin, respectively. Using the purified trypsin-like proteins, ten hybridomas which secret canine trypsin-specific monoclonal antibody were prepared. Klotz plot indicated that hybridomas, 5G2H10G4 and 2F4A11, have high affinity constant (Ka) of $4.1\;{\times}\;10^{9}$ and $1.8\;{\times}\;10^{9}$, respectively. Especially, 5F9H3 showed the cationic typsin-specific binding pattern and its Ka was determined to $4.5\;{\times}\;10^{9}$. The development of immunochromatographic test kit using these monoclonal antibodies against cTLI will be very useful in the diagnosis of canine EPI or canine pancreatitis.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.7
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• pp.71-81
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• 2014

In this paper, the performance variations of tri-gate FinFET are analyzed for different fin shapes and source/drain epitaxy types using a 3D device simulator(Sentaurus). If the fin shape changes from a rectangular shape to a triangular shape, the threshold voltage increases due to a non-uniform potential distribution, the off-current decreases by 72.23%, and the gate capacitance decreases by 16.01%. In order to analyze the device performance change from the structural change of the source/drain epitaxy, we compared the grown on the fin (grown-on-fin) structure and grown after the fin etch (etched-fin) structure. 3-stage ring oscillator was simulated using Sentaurus mixed-mode, and the energy-delay products are derived for the different fin and source/drain shapes. The FinFET device with triangular-shaped fin with etched-fin source/drain type shows the minimum the ring oscillator delay and energy-delay product.