• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1998년도 춘계학술대회 논문집
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• pp.371-373
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• 1998

The SmBa$_2$Cu$_3$O$\sub$x/ single crystals were used as seeds to induced YBCO growth in MTG process. As the result, the large bulk oriented YBCO superconductors were prepared with dimension of plane 21mm and 32mm in diameter and 10mm in height. The typical Jc value of the sample is 6.5${\times}$10$^4$A/$\textrm{cm}^2$ and its flux float force is 4.6N/$\textrm{cm}^2$. The oxygen absorption in large bulk textured YBCO samples in pure oxygen was studied at several constant temperatures. It can be divided into two steps: a chemical reaction step and a diffusion step.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1998년도 춘계학술대회 논문집
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• pp.491-493
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• 1998

The SmBa$_2$Cu$_3$O$\sub$x/ single crystals were used as seeds to induced YBCO growth in MTG process. As the result, the large bulk oriented YBCO superconductors were prepared with dimension of plane 21mm and 32mm in diameter and 10mm in height. The typical Jc value of the sample is 6.5${\times}$10$^4$A/$\textrm{cm}^2$ and its flux float force is 4.6N/$\textrm{cm}^2$. The oxygen absorption in large bulk textured YBCO samples in pure oxygen was studied at several constant temperatures. It can be divided into two steps: a chemical reaction step and a diffusion step.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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• pp.1219-1224
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• 2006

This study investigates the effect of $NH_3$ gas upon the growth of carbon nanotubes (CNTs) using thermal chemical vapor deposition. It is considered that the CNT synthesis occurs mainly through two steps, clustering of catalyst particles and subsequent growth of CNTs. We thus introduced $NH_3$ during either an annealing or growth step. When $NH_3$ was fed only during annealing, CNTs grew longer and more highly crystalline with diameters unchanged. An addition of $NH_3$ during growth, however, resulted in shorter CNTs with lower crystallinity while increased their diameters. Vertically aligned, highly populated CNT samples showed poor field emission characteristics, leading us to apply post-treatments onto the CNT surface. The CNTs were treated by adhesive tapes or etched back by dc plasma of $N_2$ to reduce the population density and the radius of curvatures of CNTs. We discuss the morphological changes of CNTs and their field emission properties upon surface treatments.

• 대한기계학회논문집
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• 제17권7호
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• pp.1700-1709
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• 1993

The stepped specimen which is subjected to step loading is modeled to study the initiation and growth of adiabatic shear band using explicit time integration finite element method. Three different clearance sizes are tested. The material model for the stepped specimen includes effects of strain hardening, strain rate hardening and thermal softening. It is found that the material inside the fully grown adiabatic shear band experiences three phase of deformation, (1) homogeneous deformation phase, (2) initiation/incubation phase, and (3) fast growth phase. The second phase of deformation is initiated after sudden shear stress drop which occurs at the same time regardless of the clearance size. The incubation time prior to fast growth phase increases, as the clearance size of the stepped specimen increases. Whereas, after incubation period, the growth rate of the adiabatic shear band decreases, as the clearance size decreases. It is also found that two adiabatic shear band may develop instead of one for the smaller clearance size.

• 한국전기전자재료학회논문지
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• 제11권1호
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• pp.12-17
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• 1998

The heteroepitaxial growth of InP and GaInAs on GaAs substrates has been studied by using a new combination of source materials: ethyldimethylindium (EDMIn) and trimethylgallium (TMGa) as group III sources, and tertiarybutylarsine (TBAs) and tertiarybutylphosphine (TBP) as group V sources. Device quality InP heteroepitaxial layers were obtained by using a two-step growth process under atmospheric pressure, involving a growth of an initial nucleation layer at low temperature followed by high temperature annealing and the deposition of epitaxial layer at a growth temperature. The continuity and thickness of nucleation layer were important parameters. The InP layers deposited at 500$^{\circ}$- 55$0^{\circ}C$ are all n-type, and the electron concentration decreases with decreasing TBP/EDMIn molar ratio. The excellent optical quality was revealed by the 4.4 K photoluminescence (PL) measurement with the full width at half maximum (FWHM) of 4.94 meV. Epitaxial Ga\ulcorner\ulcorner\ulcornerIn\ulcorner\ulcorner\ulcornerAs layers have been deposited on GaAs substrates at 500$^{\circ}$ - 55$0^{\circ}C$ by using InP buffer layers. The composition of GaInAs was determined by optical absorption measurements.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제45회 하계 정기학술대회 초록집
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• pp.281.1-281.1
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• 2013

Shape control of gold nanocrystal is still one of the most important challenges remaining to achieve geometry dependent properties. Thus far, several strategies have been developed to control the shape of nanoparticles, such as adding capping agents and diverse additives or adjusting the temperature and pH. Here, we used an already established seed-mediated method that allowed us to focus on controlling the growth stage. Cetyltrimethylammonium bromide (CTAB) and ascorbic acid (AA) were used as the ligand and the reducing agent, respectively, without using any additional additives during the growth stage. We investigated how the relative ratio of CTAB and AA concentrations could be a major determinant of nanoparticle shape over a wide concentration range of CTAB and AA. As a result, a morphology diagram was constructed experimentally that covered the growth conditions of rods, cuboctahedra, cubes, and rhombic dodecahedra. The trends in the morphology diagram emphasize the importance of the interplay between CTAB and AA. Furthermore, high-index faceted gold nanocrystal was obtained by two step seeded growth. Already synthesized cubic particles developed into hexoctahedral nanocrystal consisting of 48 identical {321} facets, which indicates that the growth of gold nanocrystal is affected by initial morphology of seed particles. The hexoctahedral gold nanoparticles can be used in catalysis and optical applications which exploiting their unique geometry. Our research can provide useful guidelines for designing various facetted geometries.

• 지식경영연구
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• 제16권1호
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• pp.71-93
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• 2015

With the rapid growth of the internet, electronic commerce has become accepted as one of the major purchasing channels for consumers. As more and more consumers search for and purchase products through the internet, intra-industry competition of electronic commerce has become fierce. Therefore, electronic commerce service providers pay attention to factors that prevent existing customers from leaving there services in the service failure situation. In this regard, electronic commerce service providers should make service recovery efforts for consumer recovery satisfaction after service failure. In this study, we suggest that procedural justice, interactional justice, distributive justice and authenticity have positive impacts on recovery satisfaction. In addition, we also propose that involvement plays moderating roles in the relationships between procedural justice, interactional justice, distributive justice, authenticity and recovery satisfaction. We collected empirical data for this study over a period of two weeks from subjects who had service failure recovery experiences through electronic commerce. A total of 224 complete and valid responses were obtained. We carried out data analysis using a two-step methodology with SPSS 20.0 and SmartPLS 2.0. The first step in the data analysis was to establish the internal consistency, convergent validity, discriminant validity of the constructs. In the second step, we examined the structural model. The empirical results support the proposed model and partly identify the moderating effect of involvement differences. The moderate effect results show that procedural justice, distributive justice and authenticity have different impacts on recovery satisfaction in two groups. Cognitive factor such as the procedural justice and distributive justice have stronger impacts on recovery satisfaction in the high-involvement goods than in the low-involvement goods, while emotional factor such as authenticity has a stronger impact on recovery satisfaction in the low-involvement goods than in the high-involvement goods. We expect that this result will provide researchers and managers who are interested in electronic commerce service failure recovery with useful theoretical and practical implications.

• 자연과학논문집
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• 제15권1호
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• pp.79-88
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• 2005

효모에는 여러 가지 종류의 thiol peroxid se 동위 효소들인 cytoplasmic TPx I, cTPx II, cTPx III, mitochodrial TPx (mTPx), 및 nuclear TPx (nTPx)가 존재하고 있다. 특히 cTPx II는 다른 효모TPx와 비교해 볼 때 매우 낮은 peroxidase 활성을 보이나, cTPx II를 제거한 cTPx II mutant균주는 심하게 성장이 저해되는 특징을 보인다. 본 연구에서는 효모에서의 cTPx II의 생리학적 기능을 밝히는 연구의 첫 과정으로 cTPx II와 상호 작용하는 단백질을 탐색하였다. Sacchromyces cerevisiae genomic DNA library에서 yeast two-hybrid system을 이용하여 cTPx II와 상호 결합하는 단백질을 탐색하여 그 단백질들의 기능을 연구하여, 궁극적으로 cTPx II의 생리기능을 밝히는데 이 연구의 목적을 두었다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2010년도 하계학술대회 논문집
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• pp.60-60
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• 2010

1-D nanostructured materials have much more attention because of their outstanding properties and wide applicability in device fabrication. Bismuth oxide($Bi_2O_3$) is an important p-type semiconductor with main crystallographic polymorphs denoted by $\alpha-$, $\beta-$, $\gamma-$, and $\delta-Bi_2O_3$[1]. Due to its unique optical and electrical properties, $Bi_2O_3$ has been extensively investigated for various applications in gas sensors, photovoltaic cells, fuel cells, supercapacitors[2-4]. In this study, $Bi_2O_3$ NWs were grown by two step annealing process: in the first step, after annealing at $270^{\circ}C$ for 10h in a vaccum($3{\times}10^{-6}$ torr), we can obtain the bismuth nanowires. In the second step, after annealing at $300^{\circ}C$ for 2h in $O_2$ ambient, we successfully fabicated $Bi_2O_3$nanowires.

• International Journal of CAD/CAM
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• 제3권1_2호
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• pp.51-60
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• 2003

The growth of the World Wide Web and the advances in high-speed network access have greatly changed existing CAD/CAE environment. The WWW has enabled us to share various distributed product data and to collaborate in the design process. An international standard for the product model data, STEP, and a standard for the distributed object technology, CORBA, are very important technological components for the interoperability in the advanced design and manufacturing environment. These two technologies provide background for the sharing of product data and the integration of applications on the network. This paper describes a distributed CAD/CAE environment that is integrated on the network by CORBA and product model data standard STEP. Several prototype application modules were implemented to verify the proposed concept and the test result is discussed. Finite element analysis server are further distributed into several frontal servers for the implementation of distributed parallel solution of finite element system equations. Distributed computation of analysis server is also implemented by using CORBA for the generalization of the proposed method.