• Journal of the Korean Ceramic Society
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• v.33 no.5
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• pp.507-513
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• 1996

Nonlinear optical properties of TeO2-PbO-GeO2 glasses were investigated and their correlation with struc-tural modification was investigated. Third-order nonlinear susceptibility $\chi$, ranged between 5.0$\times$10-13 esu and 10.7$\times$10-13 esu which are approximately 20-40 times larger than that of silica glass. The glass with a composition of 85(80TeO2-20PbO)-15GeO2(mol%) seemed to provide an optimum compromise between $\chi$and the stability against crystallization. Analyses of the Raman spectra suggested that these glasses are mainly composed of [TeO4] tbp, [TeO3]tp and [GeO4] tetrahedral structural units. It was concluded that the positive contribution of Pb2+ with high polarizability to $\chi$ in TeO2-PbO glasses overwhelmed the negative influence due to the structural modification of [TeO4]tbplongrightarrow[TeO3]tp. On the other hand addition of GeO2 in TeO2-PbO-GeO2 glasses resulted in the decrease of $\chi$ values. This behavior was attributed to the formation of [GeO4] polyhedra at the expense of [TeOn] polyhedra and Pb2+ ions which normally sowed a higher contribu-tion to $\chi$ than [GeO4] polyhedra.

• Proceedings of the Korea Electromagnetic Engineering Society Conference
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• 2003.11a
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• pp.79-83
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• 2003

Multi-port($2{\times}2$port, 1port) rectangular waveguide discontinuity problem has been analyzed by use of $TE^x_{mn}$ (mono)mode matching method. Matrix size can be reduced significantly in comparison with $TE_{mn}&TM_{mn}$(full-wave)mode matching method. the present results is compared with those by CST MicroWave Studio to validate the presint method.

• KIISE Transactions on Computing Practices
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• v.21 no.1
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• pp.46-51
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• 2015

The explosive growth of data and the rapidly changing technical social evolution new analysis paradigm for predicting and reacting the future the past and present ig data. Prescriptive analysis has a fundamental difference because can support specific behaviors and results according to user's goals with defin researchers establish judgments and activities achiev the goals. However research methods not widely implemented and even the terminology, Prescriptive analysis, is still unfamiliar. This paper thus propose an infrastructure in the prescriptive analysis field with key considerations for enhancing capability of researchers through a case study based on InSciTe Advisory developed with scientific big data. InSciTe Advisory system s developed in 2013, and offers a prescriptive analytics report which contains various As-Is analysis results and To-Be analysis results 5W1H methodology. InSciTe Advisory therefore shows possibility strategy aims to reach a target role model group. Through the availability and reliability of the measurement model the evaluation results obtained relative advantage of 118.8% compared to Elsevier SciVal.

• The Journal of the Korea Contents Association
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• v.11 no.12
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• pp.533-542
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• 2011

Visualization elements as the technology to offer information to users effectively have become more important. In this study, we evaluate the usefulness of visualization elements in InSciTe which is a technology intelligence service developed by using Semantic Web technologies and text mining technologies for establishing R&D strategy using papers and patents. We propose design which can be preferred by users and applying methods of visualization elements through the quantitative and qualitative evaluation about each types of service. As a result of evaluation, we conclude that the visualization elements in InSciTe are implemented user-friendly to improve user's cognitive intuition.

• Korean Journal of Materials Research
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• v.31 no.8
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• pp.445-449
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• 2021

Zintl compound Mg₃Sb₂ is a promising candidate for efficient thermoelectric material due to its small band gap energy and characteristic electron-crystal phonon-glass behavior. Furthermore, this compound enables fine tuning of carrier concentration via chemical doping for optimizing thermoelectric performance. In this study, nominal compositions of Mg_3.8Sb_2-xTe_x (0 ≤ x ≤ 0.03) are synthesized through controlled melting and subsequent vacuum hot pressing method. X-ray diffraction (XRD) and scanning electron microscopy (SEM) are carried out to investigate phase development and surface morphology during the process. It should be noted that 16 at. % of excessive Mg must be added to the system to compensate for the loss of Mg during melting process. Herein, thermoelectric properties such as Seebeck coefficient, electrical conductivity, and thermal conductivity are evaluated from low to high temperature regimes. The results show that Te substitution at Sb sites effectively tunes the majority carriers from holes to electrons, resulting in a transition from p to n-type. At 873 K, a peak ZT value of 0.27 is found for the specimen Mg_3.8Sb_1.99Te_0.01, indicating an improved ZT value over the intrinsic value.

• KIPS Transactions on Computer and Communication Systems
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• v.1 no.2
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• pp.61-70
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• 2012

In this study we evaluate usefulness of InSciTe Advanced, technology opportunity service offering trends information related technologies by analyzing automatically large amount of data. Before developing the service, InSciTe Advanced, we design 5 main services - Trends and Predictions, Technology Levels, Relationship Paths, Roadmaps, Competitors and Collaborators - through the interviews with expert in planning R&D strategy. And we evaluate usefulness of each service in InSciTe Advanced to examine how the information analyzed by InSciTe Advanced are useful to user from two points of view, Satisfaction of Information and Completeness of Information. Users set a high value on 5 main services in all tis aspects, but give relative low grades to completeness of Information. We will learn lessons from this study, increase kinds and amount of data, and strengthen the process about accuracy and reliability of analyzed information from the service.

• Korean Journal of Materials Research
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• v.9 no.11
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• pp.1112-1116
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• 1999

Thermoelectric effects on the temperature changes at the solid- and liquid-phase and its interface were studied by using the unidirectional solidification of $\textrm{Bi}_{2}\textrm{Te}_{3}$. Cooling or heating effects measured with current density. polarity and current passing time were quite different. By separating sole Peltier, Thomson and Joule heat theoretically and experimentally, the Peltier coefficient at the solid/liquid interface of $\textrm{Bi}_{2}\textrm{Te}_{3}$ was -1.10$\times\textrm{10}^{-1}$V, and the Thomson coefficients of solid- and liquid-phase were 7.31\times\textrm{10}^{-4}V/K, 5.77\times\textrm{10}^{-5}V/K, respectively. When D.C. passed from solid-phase to liquid-phase during the crystal growth of $\textrm{Bi}_{2}\textrm{Te}_{3}$ the crystal with more directionality was obtained owing to increase of the temperature gradient in liquid by the Peltier cooling. But in reverse current direction, the crystallinity was not changed significantly.

• Proceedings of the Materials Research Society of Korea Conference
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• 1998.08a
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• pp.50.1-50
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• 1998

• Proceedings of the Korean Information Science Society Conference
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• 2012.06b
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• pp.411-413
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• 2012

R&D 기획은 연구 개발 전주기에 있어 수행, 평가에 앞서 필수적으로 선행되어야 하는 행위이다. 그렇지만, 아직까지 R&D 기획에서 무엇을 다루어야 하는지에 대한 원칙, 사례만 존재하고 이를 통합 시스템화하지 못하고 있어, 대부분의 연구자들은 논문, 특허, 웹을 포함한 다양한 자원들로부터 정보를 수집, 취합, 분석하는 데 많은 시간을 뺏기고 있는 형편이다. 이 문제를 해결하기 위해서 본 연구 이전에 시맨틱 기술과 텍스트 마이닝 기술을 이용하여 R&D 전략 수립을 지원하고자 InSciTe, InSciTe Advanced 등이 개발되었지만, R&D 기획이라는 궁극적 목적 내에서도 사용자마다 다양한 시나리오들을 분별하여 지원하기에는 어려움이 많았다. 이에 본 연구는 사용자 적응적 가이드 방식을 통합적으로 적용하여 실시간으로 변화하는 사용자 관심을 파악하고, 대표적 시나리오들에 맞추어 사용자가 목적을 효과적으로 달성할 수 있도록 지원하는 데 초점을 맞추고자 한다. 먼저 사용자 적응적 가이드 방식의 R&D 기획 시스템 구축을 위해 필요한 요구 사항들과 이들을 효과적으로 시스템에 반영하기 위한 온톨로지, 웹 서비스 중심의 설계 원칙들을 제시함으로써 R&D 기획뿐만 아니라 타 분야에서도 유연하게 적용할 수 있는 기반을 제공한다.

• The Journal of the Korea Contents Association
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• v.12 no.12
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• pp.35-45
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• 2012

Researchers and scientists spend huge amount of time in analyzing the previous studies and their results. In order to timely take the advantageous position, they usually analyze various resources such as paper, patents, and Web documents on recent research issues to preoccupy newly emerging technologies. However, it is difficult to select invest-worthy research fields out of huge corpus by using the traditional information search based on keywords and bibliographic information. In this paper, we propose a method for efficient creation, storage, and utilization of semantically relevant information among technologies, products and research agents extracted from 'big data' by using text mining. In order to implement the proposed method, we designed an ontology that creates technological knowledge for semantic web environment based on the relationships extracted by text mining techniques. The ontology was utilized for InSciTe Adaptive, a R&D trends analysis and forecast service which supports the search for the relevant technological knowledge.