검색결과

검색조건
좁혀보기
검색필터
결과 내 재검색

간행물

    분야

      발행연도

      -

        검색결과 8

        1.
        2014.02 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구는 규모가 작고 역동적인 벤처기업의 성장에 영향을 줄 수 있는 요인들 중에서 기업의 전략적 행동이나 경영자의 경영 역량과 관련된 제품 전략과 CEO(최고경영자) 특성의 효과를 실증적으로 분석하였다. 벤처기업의 표본을 이용하여 FGLS 추정법에 기반한 회귀분석의 결과에 따르면, 제품 전략과 CEO 특성은 기업 성장에 유의한 영향을 주며 추가적인 설명력을 가진다. 일반적으로 제품의 다양화와 마케팅을 강조할수록, 변화혁신을 완화할수록 성장률이 높았다. 그리고 CEO가 경영지배력을 가진 창업자가 아니거나, 현재 사업관련 분야에서 실무경험이 많을수록 성장률이 높았다. 또한, 연구개발 위주 업무경력보다 일반경영 중심의 업무경력을 가진 CEO가 관리하는 기업이 성장률이 더 높았다. 제품 전략과 CEO 특성이 벤처기업의 성장에 미치는 이런 효과들은 조직수명주기 단계에 따라서 달라졌다. 창업기 및 초기 성장기에 있는 기업에서 제품의 마케팅 강조 전략과 CEO의 일반경영 중심 업무경력이 기업 성장에 미치는 긍정적 효과가 상대적으로 강화된 반면, 성숙기 및 정체기에 있는 기업에서 이런 제품 전략과 CEO 특성이 기업 성장에 미치는 효과가 부정적이거나 유의하지 않았다.
        8,400원
        3.
        2012.04 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        The preparation of Sm2O3 doped CeO2 in Igepal CO-520/cyclohexane reverse micelle solutions has been studied. In the present work, we synthesized nanosized Sm2O3 doped CeO2 powders by reverse micelle process using aqueous ammonia as the precipitant; hydroxide precursor was obtained from nitrate solutions dispersed in the nanosized aqueous domains of a micro emulsion consisting of cyclohexane as the oil phase, and poly (xoyethylene) nonylphenylether (Igepal CO-520) as the non-ionic surfactant. The synthesized and calcined powders were characterized by Thermogravimetry-differential thermal analysis (TGA-DTA), X-ray diffraction analysis (XRD), and Transmission electron microscopy (TEM). The crystallite size was found to increase with increase in water to surfactant (R) molar ratio. Average particle size and distribution of the synthesized Sm2O3 doped CeO2 were below 10 nm and narrow, respectively. TG-DTA analysis shows that phase of Sm2O3 doped CeO2 nanoparticles changed from monoclinic to tetragonal at approximately 560˚C. The phase of the synthesized Sm2O3 doped CeO2 with heating to 600˚C for 30 min was tetragonal CeO2. This study revealed that the particle formation process in reverse micelles is based on a two step model. The rapid first step is the complete reduction of the metal to the zero valence state. The second step is growth, via reagent exchanges between micelles through the inter-micellar exchange.
        3,000원
        5.
        2011.03 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        Nanosized Pt, Pt-Ru and Pt-CeO2 electrocatalysts supported on acid-treated carbon nanotube (CNT) were synthesized by microwave-assisted heating of polyol process using H2Cl6Pt·6H2O, RuCl3, CeCl3 precursors, respectively, and were characterized by XRD and TEM. And then the electrochemical activity of methanol oxidation for catalyst/CNT nanocomposite electrodes was investigated. The microwave assisted polyol process produced the nano-sized crystalline catalysts particles on CNT. The size of Pt supported on CNT was 7~12 nm but it decreased to 3~5 nm in which 10wt% sodium acetate was added as a stabilizer during the polyol process. This fine Pt catalyst particles resulted in a higher current density for Pt/CNT electrode. It was also found that 10 nm size of PtRu alloys were formed by polyol process and the onset potential decreased with Ru addition. Cyclic voltammetry analysis revealed that the Pt75Ru25/CNT electrode had the highest electrochemical activity owing to a higher ratio of the forward to reverse anodic peak current. And the chronoamperemetry test showed that Pt75Ru25 catalyst had a good catalyst stability. The activity of Pt was also found to be improved with the addition of CeO2.
        4,000원
        7.
        2010.07 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        The usual ceramic process of mixing and milling in state of oxides ZrO2 and CeO2 was adopted in this study in a wet process to manufacture Ce-TZP. CeO2-ZrO2 ceramics containing 8~20 mol% CeO2 were made by heat treatment at 1250~1500˚C for 5hr. The maximum dispersion point of every slurry manufactured with a mixture of ZrO2 and CeO2 was neat at pH10. A stable slurry with average particle size of 90 nm can be manufactured when it is dispersed with the use of ammonia water and polycarboxylic acid ammonium. The sintered Ce-TZP ceramics manufactured with the addition of CeO2 in a concentration of less than 10 mol% progressed to the fracture of the specimen due to the existence of a monoclinic phase of more than 30% at room temperature. More than 99% of the tetragonal phase was created for the sintered body with the addition of CeO2 beyond 18 mol%, but the degradation of the mechanical properties on the entire specimen was brought about due to the CeO2 existing in a percentage above 3%. Consequently, the optimal Ce-TZP level combined in the oxide state was identified to be 16 mol% of CeO2 contents.
        4,000원