• Macromolecular Research
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• 제13권3호
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• pp.223-228
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• 2005

In the present work, a low-density polyethylene (LDPE) composite, filled with Zn-ion coated structural silica encapsulated with the diglycidyl ether of bisphenol-A (DGEBA), was synthesized using the conventional melt-blending technique in a sigma internal mixer. The catalytic activity of the Zn-ions (originating from the structural silica) towards the oxirane group (diglycidyl ether of bisphenol-A (DGEBA): encapsulating agent) was assessed by infrared spectroscopy. Two composites, each with a filler content of $2.5 wt\%$ were developed. The first one was obtained by melt blending the Zn-ion coated structural silica with LDPE in a co-rotating sigma internal mixer. The second one was obtained by melt blending the same LDPE, but with DGEBA encapsulated Zn-ion coated structural silica. Epoxy resin encapsulation of the Zn-ion coated structural silica resulted in its having good interfacial adhesion and a homogeneous dispersion in the polymer matrix. Furthermore, the encapsulation of epoxy resin over the Zn-ion coated structural silica showed improvements in both the mechanical and thermal properties, viz. a $33\%$ increase in the elastic modulus and a rise in the onset degradation temperature from 355 to $371^{\circ}C$, in comparison to the Zn-ion coated structural silica.

• Structural Engineering and Mechanics
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• 제66권1호
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• pp.75-84
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• 2018

This study presents the reliability-based analysis of nonlinear structures using the analytical fragility curves excited by random earthquake loads. The stochastic method of ground motion simulation is combined with the random vibration theory to compute structural failure probability. The formulation of structural failure probability using random vibration theory, based on only the frequency information of the excitation, provides an important basis for structural analysis in places where there is a lack of sufficient recorded ground motions. The importance of frequency content of ground motions on probability of structural failure is studied for different levels of the nonlinear behavior of structures. The set of simulated ground motion for this study is based on the results of probabilistic seismic hazard analysis. It is demonstrated that the scenario events identified by the seismic risk differ from those obtained by the disaggregation of seismic hazard. The validity of the presented procedure is evaluated by Monte-Carlo simulation.

• 한국정보시스템학회지:정보시스템연구
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• 제33권2호
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• pp.27-45
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• 2024

Purpose The purpose of this study is to understand the important characteristics of mobile content services and to provide better content services to Chinese consumers by understanding consumer behavioral psychology about mobile content services and empirically analyzing research models with perceived usefulness, perceived enjoyment, customer attitudes, and repurchase intentions based on motivation theory. Design/methodology/approach Based on Deci(1975) Self-Determination Theory and Heijden(2004) research model, this study developed a research framework that includes perceived usefulness and perceived enjoyment to influence on repurchase intention. A questionnaire survey was conducted targeting Chinese consumers using mobile content services, and 272 valid responses were analyzed using Structural Equation Modeling (SEM). Findings According to the results of empirical analysis in this study, Chinese consumers were found to feel repurchase intention by positive impact of perceived usefulness and perceived enjoyment in the use of mobile content service. Chinese consumers still use mobile content a lot from a utilitarian perspective in relation to social life or job performance, and there is no positive effect on the use of mobile content related to perceived enjoyment. The results of this study provide the empirical results of a research model that integrates motivation theory and technology acceptance theory for the development of the mobile content industry in the future, and provide necessary insights for managers of companies that develop and distribute mobile content service.

• 정보처리학회논문지D
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• 제14D권3호
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• pp.285-292
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• 2007

XML 데이터가 웹 상의 데이터 표현 및 교환의 표준으로 각광 받음으로써, XML에 대한 관심이 증대되고 있다. XML 문서의 구조 정보는 몇 가지 중요한 역할을 수행한다. 이러한 중요성에도 불구하고 XML 문서의 구조정보는 필수 요소가 아니다. 따라서, 이러한 구조 정보를 추출하기 위한 다양한 연구들이 진행되어 왔다. 본 논문에서, 우리는 XML 문서를 위한 간결하고 정확한 DTD를 추출하는 기법을 제안한다. 특히 XML 문서의 구조 정보를 위한 DTD의 내용 모델을 DTD와 XML Schema의 혼합 내용(mixed contents)의 타당성 제약 조건을 이용하여 제한하고 본 논문에서 제안하는 몇 가지 경험적 규칙들을 적용함으로써, 우리는 간결성과 효율적을 이룩하였다. 실제 DTD를 이용한 실험을 통하여 본 논문에서 제안하는 기법이 기존의 접근 방법들에 비하여 뛰어남을 보였다.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2018년도 추계학술대회
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• pp.33-33
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• 2018

This study was conducted to examine the role of the transcription factors (TFs) (RsMYB1 and mPAP1+B-Peru) in the regulation of anthocyanin biosynthesis in the ornamental torenia cv. Kauai rose. In this study, we could produce several putative transgenic lines overexpressing the TFs via Agrobacterium-mediated transformation, and presence of the TFs in the randomly selected five transgenic lines was confirmed using polymerase chain reaction (PCR). According to results of reverse transcription-PCR analysis (RT-PCR), the expression of the TFs in all transgenic lines and of the anthocyanin structural genes (CHS, F3H, DFR, and ANS) in all transgenic lines and WT plants were distinctly detectable. However, transcript levels of the structural genes expressed in the transgenic lines overexpressing TFs were significantly higher than those expressed in WT plants. Therefore, it is suggested that anthocyanin content in flowers of the transgenic torenia would be significantly higher than that in flowers of WT plants. Moreover, these results indicate that the TFs (RsMYB1 and mPAP1+B-Peru) could be exploited as potential anthocyanin regulatory TFs to enhance anthocyanin content in the other horticultural plants.

• E2M - 전기 전자와 첨단 소재
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• 제9권4호
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• pp.404-409
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• 1996

The structural and electric properties of $Y_{1-x}$YbF$_{x}$Ba$_{2}$Cu$_{3}$O$_{7-y}$(x=0.0, 0.1, 0.2, 0.3, 0.4, 0.5 and 0.6) have been investigated by using XRD(X-ray diffraction), TMA(thennomechanical analysis), NMR(nuclear magnetic resonance) analysis and four probe method. $Y_{1-x}$YbF$_{x}$Ba$_{2}$Cu$_{3}$O$_{7-y}$ samples were prepared by conventional solid-state reaction method using $Y_{2}$O$_{3}$, BaCO$_{3}$, CuO and YbF$_{3}$ power. TMA and high temperature XRD results shows that orthorhombic to tetragonal phase transition occurs in the unfluorinated 1-2-3 sample while the phase change is not observed in the fluorinated 1-2-3 samples. Superconducting transition temperature(T$_{c}$) increases with increasing YbF$_{3}$ content ; T$_{c}$, of the sample reaching maximum of 102K for x=0.3, and then decreases with further increasing YbF$_{3}$ content. The structural analysis and T$_{c}$ results shows that the fluorine doping stabilize the orthorhombic phase, together with the increase in T$_{c}$.}$ c/.TEX> c/.

• 한국전기전자재료학회논문지
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• 제14권11호
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• pp.879-884
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• 2001

In this paper, the structural and dielectric properties of (Sr$_{l-x}$Ca$_{x}$)TiO$_3$ (0$\leq$x$\leq$0.2) -based grain boundary layer ceramics were investigated by XRD, SEM and HP4194A. The ceramics were fabricated by the conventional mixed oxide method. The sintering temperature and time were 1420~152$0^{\circ}C$ and 4 hours, respectively. The average grain size and the lattice constant were decreased with increasing content of Ca. The average grain size was increased with increase of sintering temperature. The relative density of all specimens was 96~98%. The 2nd Phase formed by the thermal diffusion of CuO from the surface leads to very excellent dielectric properties, that is, $\varepsilon$$_{r}$>50000, tan $\delta$<0.05, $\Delta$C<$\pm$10%. The appropriate Ca content was under 15 ㏖%.s under 15 ㏖%.%.

• 산업식품공학
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• 제21권4호
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• pp.341-350
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• 2017

The relationship of in vitro starch digestibility and gel strength was investigated at various concentrations (10-30%) of rice cultivars with different amylose contents (27.9, 17.9, and 5.2%). As the rice flour concentration increased, predicted glycemic index decreased, but gel strength increased regardless of amylose contents. Gel strength correlated strongly with amylose content, whereas in vitro starch digestibility was more highly affected by rice flour concentration than by amylose contents. Moreover, the impact of degree of gelatinization on in vitro starch digestibility of high amylose rice was also examined in terms of structural features and rheological properties. The digestion rate of fully gelatinized flour was 1.7 times higher than that of native flour, while the disrupted structure with a different gelatinization degree during starch digestion was visually demonstrated through the X-ray diffraction and molecular distribution analysis. The rice flour changed from an A-type to a V-type pattern and showed difference in crystalline melting. The low molecular weight distribution increased with increasing degree of gelatinization during starch digestion. The apparent viscosity also increased with degree of gelatinization. These results demonstrated that the starch digestibility of rice was more affected by concentration than by amylose content, as well as by the degree of gelatinization due to structural difference.

• 아동학회지
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• 제20권3호
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• pp.245-257
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• 1999

This study investigated illustrated Koran fairy tales as material for teaching kindergarten science. The 64 books selected for this study were analyzed by the standards set forth in the Exploring Life segment of the 5th Revision of Kindergarten Teaching Procedures (1993). The story-structure strategy was based on the structural pattern suggested by Moen(1991). Results showed that the structural elements of the illustrated fairy tales could be classified into 7 categories and 8 types of content patterns. After validating the adaptability of the fairy tales for use in teaching Kindergarten science, the books were cataloged by type and category.

• 한국정보과학회논문지:데이타베이스
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• 제30권3호
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• pp.237-251
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• 2003

이 논문에서는 비디오 데이타의 논리적 구조와 의미적 내용을 효과적으로 검색하기 위한 비디오 검색 시스템을 제안한다. 제안하는 검색 시스템은 비정형화된 비디오 데이타를 원시 데이타 계층, 내용 계층 그리고 키프레임 계층의 세 계층으로 구성하는 계층화된 모델링을 사용한다. 계층화된 모델링에 존재하는 내용 계층은 비디오 데이타에 대한 논리적인 계층 구조와 의미적 내용을 표현한다. 제안하는 검색 시스템은 모델링에 따라 텍스트 기반의 검색은 물론 시각적인 특징 기반의 유사도 검색을 지원한다. 또한 시공간 관계에 기반한 의미적 내용 검색과 유사도 검색을 지원한다.