• Journal of the Korean Data and Information Science Society
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• 제22권6호
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• pp.1251-1256
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• 2011

Consider a p-variate ($p{\geq}4$) normal distribution with mean ${\theta}$ and identity covariance matrix. Using a simple property of noncentral chi square distribution, the generalized Bayes estimators dominating the Lindley estimator under quadratic loss are given based on the methods of Brown, Brewster and Zidek for estimating a normal variance. This result can be extended the cases where covariance matrix is completely unknown or ${\Sigma}={\sigma}^2I$ for an unknown scalar ${\sigma}^2$.

• Communications for Statistical Applications and Methods
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• 제12권2호
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• pp.463-472
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• 2005

In this paper, the problem of estimating a p-variate (p $\ge$4) normal mean vector is considered in decision-theoretic set up. Using a simple property of the noncentral chi-square distribution, a sequence of estimators dominating the Lindley type estimator with the cases of unknown covariance matrices has been produced and each improved estimator is better than previous one.

• 한국건축시공학회지
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• 제8권4호
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• pp.79-85
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• 2008

The purpose of this study is to evaluate the mix design of pH reducing cement concrete which can be used for environment-friendly concrete. Cement pastes and concretes are prepared with water-binder ratios and various admixtures such as blast-furnace slag, fly ash and recycled cement, and tested for compressive strength and pH. pH is measured through pore solution expressed from hydrated cement paste by special apparatus. From the test results, regardless of water-binder ratio, The pH of expressed pore solution from hydrated cement paste which is made of ordinary portland cement with blast-furnace slag, fly ash is decreased with increasing of admixtures content, and compressive strength is also slightly improved. The compressive strength of cement paste made of recycled cement which is burnt at $1000^{\circ}C$, for 2 hours is considerably increased compared with that of none-burnt recycled cement due to restoration of hydraulic property, but pH is a little higher. Porous concrete with ordinary portland cement has high pH in the range of 12.22 to 12.59, however, that is reduced to the range of 8.95 to 10.39 by carbonation at the surface of porous concrete. The pH reduction of porous concrete is possible by various admixture addition, however their degrees are very slight. Therefore, to reduce the pH considerably, carbonation method of porous concrete is better in pH reduction methods for plant survival condition of pH of 9.0 or less. In this study, it is apparent that pH for the environment-friendly porous concrete products used in the construction field can be suppressed by this carbonation method and various admixtures addition.

• 한국자기공명학회논문지
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• 제11권2호
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• pp.110-114
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• 2007

[ $^{31}P$ ] powder pattern spectra were measured to investigate the aspects of the interaction between the MLV (Multilamellar vesicle) and PMAP-23, a membrane of cathelicidin family and then CSAs(chemical shift anisotropy) were calculated to indentify the extent of perturbation of phospholipid mobility by the peptides. We found that acidic phospholipid interacts strongly with PMAP-23, and the analogues which modified to increase the amphipathic property showed that larger change of CSA. The analogue which introduced positive charge showed the same effects with amphipathic property.

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• 제1권2호
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• pp.167-175
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• 1997

This study was conducted for an efficient utilization of waste fly ash obtained from the power plant. Fly ash was used for synthesizing zeolite. Na-P1 zeolite could be easily synthesized from waste fly ash and showed the potential to remove heavy metal ions. The synthetic zeolite showed good adsorption property for heavy metal much better than raw fly ash and natural zeolites. Na-P1 exhibited the high adsorption efficiency with a maximum value of 260 Pb mg/g and strong affinity for $Pb^{2+}$ ion. The metal ion selectivity of Na-P1 was determined in a decreasing order : $Pb^{2+}>Cd^{2+}>Cu^{2+}>Zn^{2+}>Fe^{3+}$.

• Biomolecules & Therapeutics
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• 제9권4호
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• pp.298-306
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• 2001

To develop a novel transdermal delivery system of loxoprofen (LP), a potent antiinflammatory and analgesic agent, the effects of vehicle composition and drug loading dose on the skin permeation property were investigated. And in vivo skin absorption property studied by analysing the $C_{max}$ and AUC was investigated after applying the developed plaster systems on rabbit back skin. Addition of isopropyl myristate (IPM) and IPM-diethylene glycol monoethyl ether (DGME) cosolvent in the plaster showed higher permeation rates than those from propylene glycol laurate-DGME cosolvent systems. As the concentration of LP in the plaster increased from 0.56 mg/$\textrm{cm}^2$ to 1.19 mg/$\textrm{cm}^2$, the drug release and skin permeation rates increased linearly. At loading dose of 1.19 mg/$\textrm{cm}^2$, the flux reached 35.6 $\mu$g/$\textrm{cm}^2$/hr. New LP plasters showed a good adhesive property onto skin, and showed no crystal formation. The AU $C_{0-24hr}$ and $C_{max}$ after dermal application of LP plaster (60 mg/70 $\textrm{cm}^2$) were found to be 6951$\pm$230 ng.hr/ml and 400$\pm$44 ng/ml, respectively. And the plasma concentration maintained above 300 ng/ml up to 24 hr period. In the carrageenan-induced rat paw edema test, LP plaster showed similar inhibition rate with marketed ketoprofen (Ketoto $p^{R}$) plaster.aster.r.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 추계학술대회 논문집 Vol.14 No.1
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• pp.374-377
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• 2001

We have synthesized poly(3-hexylthiophene)(P3HT), which is the most famous conducting polymer and studied the optical properties of P3HT. And then fabricated the device using P3HT as an emitting layer. For the improve of hole injection from ITO electrode to P3HT emitting layer, we use transparent polyaniline(PANI) electrode. In the voltage-current-luminance characteristics of ITO/PANI/P3HT/LiF/Al device which use the PANI film synthesised during 5 cycle, the device turn on at the 2V and the luminance of $218nW/cm^{2}$ obtained at 12V. External quantum efficiency of ITO/PANI/P3HT/LiF/Al increased at 8V than that of ITO/P3HT/LiF/Al device.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 추계학술대회 논문집
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• pp.374-377
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• 2001

We have synthesized poly(3-hexylthiophene)(P3HT), which is the most famous conducting polymer and studied the optical properties of P3HT. And then fabricated the device using P3HT as an emitting layer. For the improve of hole injection from ITO electrode to P3HT emitting layer, we use transparent polyaniline(PANI) electrode. In the voltage-current-luminance characteristics of ITO/PANI/P3HT/LiF/Al device which use the PANI film synthesised during 5 cycle, the device turn on at the 2V and the luminance of 218 nW/$\textrm{cm}^2$ obtained at 12V. External quantum efficiency of ITO/PANI/P3HT/LiF/Al increased at 8V than that of ITO/P3HT/LiF/Al device.

• 접착 및 계면
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• 제7권2호
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• pp.19-25
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• 2006

미생물 합성 고분자인 poly(hydroxylalkanoate)s (PHAs)의 초기효소분해는 표면침식의 메커니즘으로 진행하므로 이들의 분해거동은 표면특성을 개질로서 조절할 수 있다. 본 연구에서는 효소분해속도를 조절하기 위하여 플라즈마 기법을 PHAs 표면특성의 개질에 적용하였다. $CF_3H$와 $O_2$ 플라즈마를 사용하여 재료 표면에 각각 소수성 및 친수성을 부여하였다. 효소분해 실험은 pH 7.4의 0.1 M potassium phosphate 완충용액에서 Alcaligenes facalis T1에서 정제된 poly(hydroxybutyrate) 분해효소를 첨가하여 행하였다. $CF_3H$ 플라즈마 처리된 시편의 경우 표면 층의 불소화에 따른 소수성의 증가와 분해 효소에 대한 비활성으로 초기분해 속도가 상당히 지연됨을 관찰하였으나 $O_2$ 플라즈마 처리에 의한 표면 친수성은 분해속도의 촉진 등에 큰 영향을 미치지 않았다.

• 한국환경생태학회지
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• 제21권6호
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• pp.487-493
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• 2007

지리산 국립공원 동부지 역에 위치한 중산리, 백무동, 대원사 산구야영장 등 4개의 야영장조성지와 인접한 산림지역의 토양 특성을 비교한 결과 토양용적밀도, 토양경도, 토양 pH, 투수율, 토양호흡율 등의 토양 특성은 산림지역과 야영장 조성지 사이에 차이가 있었다(p<0.05). 그러나 표토($0{\sim}15cm$)와 심토($15{\sim}30cm$) 사이에 깊이별 토양특성은 야영장 조성지와 산림지역 모두 차이가 없었다(p>0.05). 토양용적밀도의 경우 산림지역 $0.95g/cm^3$, 야영장 조성지 $1.29{\sim}1.44g/cm^3$로, 야영장 조성지가 산림지역에 비해 높았으며, 토양경도는 산림지역 $1.44kg/cm^2$, 야영장 조성지 $2.9{\sim}4.0kg/cm^2$로 유의적인 차이가 있었다(p<0.05). 토양공극율의 경우 산림지역은 64.3%로 야영장 조성지 $45.7{\sim}51.4%$에 비해 높았고, 토양 PH는 산림지역 pH 5.46, 야영장 조성지 $pH\;5.49{\sim}pH\;6.38$ 범위에 분포하였다. 투수율의 경우산림지역 18.7cc/초, 야영장 조성지 $0.79{\sim}2.06cc$/초, 토양호흡율은 산림지역 $0.58gCO_2/m^2/h$로, 야영장 조성지 $0.13{\sim}0.34gCO_2/m^2/h$에 비해 높게 나타났다.