• Fibers and Polymers
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• v.4 no.4
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• pp.156-160
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• 2003

Poly(ethylene 2,6-naphthalate) (PEN)/Poly(ethylene glycol) (PEG) copolymers were synthesized by two step reaction during the melt copolymerization process. The first step was the esterification reaction of dimethyl-2,6-naphthalenedicarbox-ylate (2,6-NDC) and ethylene glycol (EG). The second step was the condensation polymerization of bishydroxyethylnaphthalate (BHEN) and PEG. The copolymers contained 10 mol% of PEG units with different molecular weights. Structures and thermal properties of the copolymers were studied by using $^1{H-NMR}$, DSC, TGA, etc. Especially, while the intrinsic viscosities of PEN/PEG copolymers increased with increasing molecular weights of PEG, but the glass transition temperature, the cold crystallization temperature, and the weight loss temperature of the copolymers decreased with increasing molecular weights of PEG. Consequently, the hydrophilicities by means of contact angle measurement and moisture content of the copolymer films were found to be significantly improved with increasing molecular weights of PEG.

• Proceedings of the IEEK Conference
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• 2005.11a
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• pp.679-682
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• 2005

Negative-differential conductance (NDC) characteristics as well as negative-differential trans-conductance (NDT) characteristics have been observed in the room temperature I-V characteristics of Field-induced Inter-band Tunneling Effect Transistors (FITETs). These characteristics have been explained with inter-band tunneling physics, from which, inter-band tunneling current flows when the energy bands of degenerately doped regions align, and it does not flow when they don't. FITET is an SOI device and the body region is not directly connected to the external terminal. Therefore, Fermi energy in the body region is determined by electrical coupling among four regions - gate, source, drain and substrate. So, a quasi Fermi energy of the majority carriers in the floating body region can be changed by external voltages, and this causes the energy band movements in the body region, which determine whether the energy bands between degenerately doped junctions aligns or not. This is a key point for an explanation of NDT and NDC characteristics. In this paper, a quasi Fermi energy movement in the floating body region of FITET was investigated by a device simulation. This result was applied for the description of relation between quasi Fermi energy in the body region and external gate bias voltage.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.2
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• pp.202-209
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• 2018

This study analyzed the effects of the nutrient intake on oral health and chewing difficulty according to the age group. The subjects were 5,855 participants of the third Korea National Health and Nutrition Examination Survey(KNHANES VI), 2015, Korea Centers for Disease Control and prevention and aged 20 years and over. The data were analyzed using SPSS Ver 21.0, classified as the difficulty in chewing group (DC) and no difficulty in chewing group (NDC). As a result, the DC rates were 5 times higher in the 60+ year age group (39.5%) than in the 20-39 year age group (8.1%). The DC group were experience periodontal disease (33.4%), dental caries (30.1%), diabetes (41.8%), myocardial infarction (57.3%), arthritis (44.0%), asthma (48.0%), and depression (41.9%). In addition, 86% of the DC group were experiencing speech problems. The DC group had significantly lower intakes (1446.59g), than the NDC group (1666.62g), and the protein, carbohydrate, dietary fiber and other dietary intake were significantly lower. These findings suggest that the chewing difficulty is related to the nutrient intake, and psychological status in the elderly DC group. Therefore, the care of chewing difficulties is essential for the elderly to maintain a healthy lifestyle. Accordingly, oral care and myofunctional therapy are needed to maintain oral health.

• Journal of Korean Library and Information Science Society
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• v.19
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• pp.35-57
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• 1992

This study is an attempt to provide some helpful data for the design and the implementation of the expert system for the book-classification based on the analysis of various cases of the classification-expert system models. Following the introduction, the concepts and some features of an expert system were overviewed in the second chapter, on the basis of which the following concrete cases were introduced and analyzed in the third chapter : (1) ACN System for NC, (2) Expert System for NDC, (3) Expert System for UDC, (4) Herba Medica System, (5) Expert System for IPC, (6) Stratcyclode Project, (7) Expert System for Classification of INIS Database, (8) AutoBC System, and etc. In the conclusion, for the development of the classification-expert system, it was turned out that constructing a new system by using an AI language such as Prolog or LISP is more desirable than employing any one of expert system shells. Together it is necessary for the following requirements to be met : (1) The subject concept of a document elicited should be accurate. (2) Not only a domain knowledge but also the knowledge covering all the subjects should be represented in the knowledge-bases. (3) The knowledge-bases should be organized in such a way that the characteristics of the knowledge about classification should be well defined. (4) rule-base consisting of accurate rules about classification should be made. (5) It should be possible for classification code wanted to be generated immediately.

• Journal of the Korean Society for information Management
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• v.31 no.3
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• pp.7-27
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• 2014

Constructions and Architecture fields were divided into Architecture engineering and Architecture in the 5th edition of Korean Decimal Classification (KDC), but those were combined in the 6th edition of KDC published in 2013. The purposes of this study are to find problems and to suggest modifications through comparing and analyzing the 5th and the 6th editions of KDC, Dewey Decimal Classification, Nippon Decimal Classification and Universal Decimal Classification. The necessity of reclassification, a long classification number for History of Architecture and addition of categories of traditional building and architectural engineering are required to improve the 6th edition of KDC and the improvements and modifications of those problems are suggested.

• Journal of Korean Library and Information Science Society
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• v.35 no.2
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• pp.135-154
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• 2004

This study was investigated to the geographical categories and arrangement of library classifications and public organizations in ender to understand the geographical category comprehension and canon from the north-west to south-east in Korean library classification and then to develop a Korean geographical classification system Research method was the examination of different type of library classification (DDC, NDC, LCC) and geographical categorizations of the public organizations. The results show that there was not a principle of categorization and arrangement for geographical information. This study proposes to the three hierarchical structures and radial category arrangement from center-area to side area for developing Km geographical classification.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.05c
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• pp.201-203
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• 2001

This paper describes the information for quantitative simulation of weakly ionized plasma. We must grasp the meaning of the plasma state condition to utilize engineering application and to understand materials of plasma state. In this paper, the drift velocity of electron in Xenon gas calculated for range of E/N values from 0.01~500[Td] at the temperature is $300[^{\circ}K]$ and pressure is 1[Torr], using a set of electron collision cross sections determined by the authors and the values of drift velocity of electrons are obtained for TOF, PT, SST sampling method of Backward Prolongation by two term approximation Boltzmann equation method. it has also been used to predict swarm parameter using the values of cross section as input. The result of Boltzmann equation, the drift velocity of electrons, has been compared with experimental data by L. S. Frost and A. V. Phelps for a range of E/N. The swarm parameter from the study are expected to server as a critical test of current theories of low energy scattering by atoms and molecules.

• Journal of Applied Biological Chemistry
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• v.43 no.3
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• pp.152-155
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• 2000

The contents of various capsaicinoids viz. nordihydrocapsaicin (NDC), capsaicin (CAP), and dihydrocapsaicin (DHC) were determined in different parts of fruits (placenta, pericarps, seeds, and whole fruits) at different developmental stages after flowering and compared with the capsaicinoid synthetase (CS) activity. The capsaicinoid contents were very low up to 24 days after flowering (DAF), and there was a significant increase at 36 DAF in all parts of fruits. The enzyme activity of placenta increased to maximum at 24 DAF, and thereafter it gradually decreased. There were no significant amounts of enzyme activities in other parts of the fruits. In Subicho (inbred line) the content of DHC was slightly higher than CAP in all parts. of the fruits throughout the development stages of fruits, whereas in Chung Yang the CAP content was higher compared to the DHC content. The contents of total capsaicinoids in Chung Yang were also higher than Subicho. However, the crude enzyme extract obtained from Chung Yang led to the synthesis of DHC almost exclusively when the substrate, 8-methyl nonanoic acid, was added to the reaction mixture. Our results suggest that the composition of individual analogue of capsaicinoids depends upon the substrate available in the fruits.

• Proceedings of the Korea Technology Innovation Society Conference
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• 2017.11a
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• pp.1489-1506
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• 2017

'신기후체제 대응' 이라는 범국가적 미션 뿐 만 아니라 현재 국내에서의 원자력계 입지를 고려할 때 원자력계의 적극적인 대처와 전략이 필요한 상황이다. 본 연구는 기후기술과 기술협력의 중요성에 주목하여 연구기관 및 관련 기업이 현재 보유 혹은 개발 중이거나 향후 개발 가능한 온실가스 감축 및 기후변화 적응에 활용 가능한 기술과 연구분야를 발굴하기 위해 추진되었다. 이를 위해 한국원자력연구원 및 연구원 Family 기업을 대상으로 총 3회의 조사를 시행하였다. 이를 통해 원자력발전을 통한 온실가스 감축 기여 외에도 원자력계 내에 온실가스 감축과 기후변화 적응 기술을 다양하게 보유하고 있음을 증명하였고, 정책적 시사점을 도출하였다. 국가 주도의 기후기술 연구 전략이 성공적으로 수립 이행되기 위해서는 연구 및 정책 분야 전문가들의 기후기술에 대한 명확한 이해와 정부의 지원이 필요하다. 마지막으로 기술 활용 혹은 개도국으로의 이관 시 국가 NDC 달성에 얼마만큼 영향을 미치는지에 대한 성과 측정 기준이 확정 된다면 향후 고도화된 연구개발 전략 수립은 물론, 연구자들의 참여도를 이끌어 낼 수 있을 것이라 판단한다.

• Journal of Radiation Protection and Research
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• v.41 no.3
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• pp.191-195
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• 2016

Background: The current status of ACE format MCNP/MCNPX libraries by NDC of KAERI is presented with a short description of each library. Materials and Methods: Validation calculations with recent nuclear data evaluations ENDF/BV-II. 0, ENDF/B-VII.1, JEFF-3.2, and JENDL-4.0 have been carried out by the MCNP5 code for 119 criticality benchmark problems taken from the expanded criticality validation suite supplied by LANL. The overall performances of the ACE format KN-libraries have been analyzed in comparison with the results calculated with the ENDF/B-VII.0-based ENDF70 library of LANL. Results and Discussion: It was confirmed that the ENDF/B-VII.1-based KNE71 library showed better performances than the others by comparing the RMS errors and ${chi}^2$ values for five benchmark categories as well as whole benchmark problems. ENDF/B-VII.1 and JEFF-3.2 have a tendency to yield more reliable MCNP calculation results within certain confidence intervals regarding the total uncertainties for the $k_{eff}$ values. Conclusion: It is found that the adoption of the latest evaluated nuclear data might ensure better outcomes in various research and development areas.