• 한국세라믹학회:학술대회논문집
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• 한국세라믹학회 2004년도 춘계총회 및 연구발표회 초록집
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• pp.36.3-36.3
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• 2004

• 한국전기전자재료학회논문지
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• 제13권11호
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• pp.908-913
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• 2000

CoSi$_2$/p+/n diodes(bilayer diodes) were fabricated by using epitaxial CoSi$_2$grown from Co/Ti bilayer as a diffusion source. The I-V characteristics of p+/n diodes were measured and compared with those of diode made from Co monolayer (monolayer diode). Monolayer diodes showed typical p+n junction characteristics with the leakage current of as low as 10$^{-12}$ A and forward current 6-orders higher than the leakage current, when drive-in annealed at 90$0^{\circ}C$ for 20 sec.. On the other hand, bilayer diodes showed the Schottky-like behaviors with forward currents rather higher than those of monolyer diodes, but with too high leakage currents, when drive-in annealed at $700^{\circ}C$ or higher. However, when the annealing temperature was lowered to $700^{\circ}C$ and annealing time was increased to 60 sec., the leakage current was reduced to 10$^{-11}$ A and thus sho3wed typical diode characteristics. The high leakage currents for diodes annealed at $700^{\circ}C$ or higher was attributed to Shannon contacts formed due to unremoved Co-Ti-Si precipitates. But when annealed at 50$0^{\circ}C$, B ions diffused in the direction of the surface layer, and thus the leakage currents were reduced by removing Shannon contacts.

• The Korean Journal of Ecology
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• 제18권2호
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• pp.255-263
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• 1995

Two poplar clones, I-214 (Populus euramericana) and Peace (P. Koreana × P. trichocarpa), were grown for 21 days in growth chambers at different CO₂concentrations (350, 700 and 2,000 μL·L-1). I-214 has stomata responding to environmental conditions in normal ways and Peace has unresponsive stomata to environmental factors including light, ABA, water stress and CO₂. In both plants, elevated CO₂ stmulated the growth of plant parts, especially leaf dry weight. And a CO₂ enrichment of 700 μL·L-1 CO₂ caused increment of net assimilation rate (NAR). The growth responses of these plants to CO₂ enrichment were different especially at high CO₂ condition (2,000 μL·L-1 CO₂). The total dry weight in Peace increased up to 2,000 μL·L-1 CO₂ but not in I-214. A CO₂ enrichment of 2,000 2,000 μL·L-1 CO₂ had little effect on NAR of I-214 but enhanced NAR of Peace. Although it is uncertain whether the different responses to CO₂ enrichment between I-214 and Peace resulted from the different properties of stomatal responses to long-term CO₂ treatment, the decrease in NAR is probably due in part to CO₂-induced stomatal closure in I-214 but not in Peace.

• 지식경영연구
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• 제14권5호
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• pp.35-53
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• 2013

This paper aims to describe how knowledge management could be put into practice in a voluntary way. From a practice-based standpoint, this study focused closely on the linkage between knowledge and practice. It is because knowledge management could fail if not put into practice. Using its own information system, iCOOP, a federation of consumers' co-operatives in Korea has been practised successful knowledge management voluntarily with its members. Based on the exploratory case study on iCOOP, this study conducted focused interviews with 5 member co-operatives of iCOOP. Main findings are as follows. First, an NoP emerges within a corporate information system when corporate work processes are concentrated in the information system. Second, corporate information system facilitates CoPs and the NoP when its information and information about its users are opened to all of the information system users. In conclusion, this study points out that it is not the matter of primary importance to build a knowledge management system. Rather, practice has the key to the successful knowledge management.

• Bulletin of the Korean Chemical Society
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• 제21권11호
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• pp.1125-1132
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• 2000

The pH effect of the precursor solution on the preparation of $LiCoO_2$ by a solution phase reaction containing malonic acid was carried out. Layered $LiCoO_2$ powders were obtained with the precursors prepared at the different pHs (4, 7, and 9) and heat-treated at $700^{\circ}C(LiCoO_2-700)$ or $850^{\circ}C(LiCoO_2-850)$ in air. pHs of the media for precursor synthesis affects the charge/discharge and electrochemical properties of the $LiCoO_2electrodes.$ Upon irrespective of pH of the precursor media, X-ray diffraction spectra recorded for $LiCoO_2-850$ powder showed higher peak intensity ratio of I(003)/I(104) than that of $LiCoO_2-700$, since the better crystallization of the former crystallized better. However, $LiCoO_2$ synthesized at pH 4 displayed an abnormal higher intensity ratio of I(003)/I(104) than those synthesized at pH 7 and 9. The surface morphology of the $LiCoO_2-850$ powders was rougher and more irregular than that of $LiCoO_2-700$ made from the precursor synthesized at pH 7 and 9. The $LiCoO_2electrodes$ prepared with the precursors synthesized at pH 7 and 9 showed a better electrochemical and charge/discharge characteristics. From the AC impedance spectroscopic experiments for the electrode made from the precursor prepared in pH 7, the chemical diffusivity of Li ions (DLi+) in $Li0.58CoO_2determined$ was 2.7 ${\times}$10-8 $cm^2s-1$. A cell composed of the $LiCoO_2-700$ cathode prepared in pH 7 with Lithium metal anode reveals an initial discharge specific capacity of 119.8 mAhg-1 at a current density of 10.0 mAg-1 between 3.5 V and 4.3 V. The full-cell composed with $LiCoO_2-700$ cathode prepared in pH 7 and the Mesocarbon Pitch-based Carbon Fiber (MPCF) anode separated by a Cellgard 2400 membrane showed a good cycleability. In addition, it was operated over 100 charge/discharge cycles and displayed an average reversible capacity of nearly 130 mAhg-1.

• 충청수학회지
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• 제30권1호
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• pp.129-139
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• 2017

For a map $p:X{\rightarrow}A$, there are concepts of co-$H^p$-spaces, co-$T^p$-spaces, which are generalized ones of co-H-spaces [17,18]. For a principal cofibration $i_r:X{\rightarrow}C_r$ induced by $r:X^{\prime}{\rightarrow}X$ from $\imath:X^{\prime}{\rightarrow}cX^{\prime}$, we obtain some sufficient conditions to having extensions co-$H^{\bar{p}}$-structures and co-$T^{\bar{p}}$-structures on $C_r$ of co-$H^p$-spaces and co-$T^p$-structures on X respectively. We can also obtain some results about co-$H^p$-spaces and co-$T^p$-spaces in homology decompositions for spaces, which are generalizations of Golasinski and Klein's result about co-H-spaces.

• 대한화학회지
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• 제44권4호
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• pp.305-310
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• 2000

일정한 이온강도(0.1M)에서 알루미나에 의한 Ni(II), Co(II), Sr(II) 및 Cs(I)의 흡착거동을 세 가지의 금속이온 농도를 사용하여 pH를 변화시키면서 관찰하였다. 금속 이온의 농도가 증가할수록 흡착률은 감소했으며 흡착변곡점이 보다 높은 pH쪽으로 이동하였다. 금속 이 온의 농도가 $1.0{\times}10^{-4}$M인 조건에서 측정한 흡착데이터로부터 표면착물 모델을 적용하여 각 금속의 흡착종에 대한 고유의 흡착상수 값을결정하였다. 흡착 세기는 Co(II)>Ni(II)>Sr(II)순으로 감소하였으며 Cs(I)는 흡착이 되지 않았다. 높은 pH에서의 Co(II)와 Ni(II)의 흡착성이 대부분이 가수분해된 형태로 존재하였다.

• 농약과학회지
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• 제10권1호
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• pp.7-14
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• 2006

새로운 5-benzofuryl-2-[1-(alkoxyimino)alkyl]-3-hydroxycyclohex-2-en-1-one 유도체들의 3차원적인 정량적 구조와 발아 전, 벼(Oryza sativa L.)와 논피(Echinochloa crus-galli)에 대한 제초활성과의 관계를 비교분자 유사성 지수분석(CoMSIA) 방법으로 연구하였다. 가장 양호한 CoMSIA 모델로서 벼에 대한 A5 모델($r^2_{cv.}=0.569$ 및 $r^2_{ncv.}=0.941$)은 주로 소수성장(39.7%)과 입체장(31.6%) 그리고 논피에 대한 B4 모델($r^2_{cv.}=0.595$ 및 $r^2_{ncv.}=0.933$)은 정전기장(46.7%)과 수소결합 받게장(30.8%)에 각각 의존적이었다. B4 모델에 의하여 예측된 $R_1=SF_5,\;R_2=R_3=R_4=H(P1)$ 치환체(벼: $pI_{50}=4.84$ 및 논피: $pI_{50}=7.21$, ${\Delta}pI_{50}=2.37$)는 논피에 대하여 가장 높은 제초활성을 나타내었으며 두 초종 간 선택성이 가장 큰 치환체이었다.

• 호남수학학술지
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• 제30권3호
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• pp.425-433
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• 2008

In this paper, we introduce the concept of p-preconvex sets on preconvexity spaces. We study some properties for p-preconvex sets by using the co-convexity hull and the convexity hull. Also we introduce and study the concepts of pc-convex function, $p^*c$-convex function, pI-convex function and $p^*I$-convex function.

• 공업화학
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• 제10권1호
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• pp.6-11
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• 1999

방청제로 dialkylaminc (di-)nitrobenzoates 14개 화합물을 합성하고 첨가제 효과와 함께 방청성능을 조사하였다. 합성화합물은 원소분석, FT-IR, $^1H$-NMR 분석으로 확인하였으며, 합성한 화합물과 첨가제 [$(NH_4)_2CO_3$, $NaHCO_3$]의 방청성능은 방청제를 1 M $Na_2SO_4$ 용액에 1% (w/v) 용해시켜 potentiostatic method로 분극실험하여 조사하였다. 철에 대해 dialkylamine 3, 5-dinitrobenzoates보다 dialkylamine 4-nitrobenzoates 부동태화 전류밀도 ($i_p$)가 작았으며, diethylamine 4-nitrobenzoate 용액에서 낮은 값 ($i_p$; $4.78mA/cm^2$)을 나타내었다. 비철에 대한 $i_p$값은 dialkylamine 3, 5-dinitrobenzoates가 작았고 dipropylamine 3, 5-dinitrobenzoate와 hexamethyleneimine 3, 5-dinitrobenzoate가 낮은 값 ($i_p$; 36, $37mA/cm^2$)을 나타냈다. 방청제에 $(NH_4)_2CO_3$와 $NaHCO_3$ 첨가효과는 철에 대해 높은 부식억제 효과를 나타냈으나, 비철에서는 좋은 결과를 얻지 못하였다. 철용 방청제 diethylamine 4-nitrobenzoate와 $(NH_4)_2CO_3$, $NaHCO_3$의 최적 혼합비율은 4 : 6과 5 : 5이며, 부동태화 전류밀도 ($i_p$)는 0.26, $0.85mA/cm^2$의 최소값을 각각 나타내었다.