• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.43 no.2
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• pp.40-48
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• 2011

To build up the conservativeness of aged paper heritages, the strength reinforcement treatment using various cellulose derivative solutions was considered. Hand-made Hanji prepared by traditional papermaking technique was firstly simulated in order to modify the overall of paper properties like aged paper heritages by accelerated ageing treatment at $150^{\circ}C$ for 24 hours, and then the ageing stability of Hanji was verified through the secondary accelerated ageing at $150^{\circ}C$ for 12 hours. The physical properties of aged Hanji were improved by applying with cellulose derivative solutions. The ageing stability for physical, optical (L, brightness, opacity, yellowness) and chemical (oxidation index, degree of polymerization) properties of aged Hanji treated with all kinds of cellulose derivative solutions was also good compared to those of untreated samples, especially using MC solution. Therefore, it was that a kind of MC solution would be well-suited for the strength reinforcement treatment of aged paper heritages.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.43 no.2
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• pp.66-71
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• 2011

Biocomposites were fabricated with biodegradable polymers and natural fibers. Biocomposites have benefits of low cost, low density, and biodegradability over inorganic fiber composite, and give comparable strength properties. Hydrophobic polymer used for sizing in paper industry, AKD (Akenyl Keten Dimer), was applied to natural fibers, red algae fibers (RAF) in this study, to make fiber surfaces more compatible to hydrophobic nature of matrix polymers. Composites with RAF, kenaf, glass fibers, and carbon fibers have been fabricated by a compression molding method and their thermo-mechanical properties have been studied. Also, the thermal dimensional stability test was done from at 30 to $100^{\circ}C$. The storage moduli and the thermo-mechanical stabilities of polypropylene and poly lactic acid based biocomposites were improved by reinforcing with the RAF and much more with AKD treated fibers. Dimensional stability of biocomposite was also markedly improved by AKD pretrement on RAF.

• International Journal of Computer Science & Network Security
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• v.21 no.8
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• pp.119-126
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• 2021

The study develops methodological aspects for modeling the determining impact of modernization on the enterprise's economic security in development competitive conditions using the model of speed, stability and spaciousness of modernization. Modeling the determining impact of modernization on the enterprise's economic security in a competitive conditions involves: firstly, the formation of estimated modeling indicators in accordance with the speed, stability and spaciousness of the enterprise's modernization; secondly, establishing the weight of indicators in the assessment system using the tools of cognitive judgment; thirdly, the establishment of reference values of sound evaluation indicators; fourthly, the calculations of the integrated impact assessment of the modernization's determining impact modeling on the enterprise's ensuring economic security in a competitive conditions; fifthly, conducting calculations and analytical summarization of the results. To determine a comprehensive integrated indicator of the modernization changes impact on the competitiveness and economic security of enterprises, we use the correlation method of the calculated value with the reference value, as well as use weights for groups of calculations. Approbation of modeling of determining influence of modernization on maintenance of economic safety of the enterprise in competitive conditions of development by authors was carried out concerning such enterprises, as: JSC "Ukrzaliznytsia", SE "Ukraerorukh", SE IA "Boryspil", SE "Ukrposhta", KP "Kyivpastrans".

• Advances in nano research
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• v.16 no.5
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• pp.445-458
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• 2024

The objective of this paper is to present free vibration and static stability analyses of rotating composite beams reinforced with carbon nanotubes (CNTs) under uniform thermal loads. Beam structural equations and CNT-reinforced composite (CNTRC) beam formulations are derived based on Timoshenko beam theory (TBT). The temperature-dependent properties of the beam material, such as the elastic modulus, shear modulus, and material density, are assumed to vary over the thickness according to the rule of mixture. The beam material is modeled as a mixture of single-walled carbon nanotubes (SWCNTs) in an isotropic matrix. The SWCNTs are aligned and distributed in the isotropic matrix with different patterns of reinforcement, namely the UD (uniform), FG-O, FG-V, FG- Λ and FG-X distributions, where FG-V and FG- Λ are asymmetric patterns. Numerical examples are presented to illustrate the effects of several essential parameters, including the rotational speed, hub radius, effective material properties, slenderness ratio, boundary conditions, thermal force, and moments due to temperature variation. To the best of the authors' knowledge, this study represents the first attempt at the finite element modeling of rotating CNTRC Timoshenko beams under a thermal environment. The results are presented in tables and figures for both symmetric and asymmetric distribution patterns, and can be used as benchmarks for further validation.

• Proceedings of the KSME Conference
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• 2008.11b
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• pp.2519-2523
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• 2008

When constructing a high-speed railroad, the reduction of the distance between track centers and the width of track bed will save the construction cost. However the shortening the distance between track centers may cause the stability problems due to higher wind pressure. Therefore the extensive technical review and aerodynamical study should be performed to determine the adequate distance between track centers. In this study, the impact that the increase in wind pressure due to the change of aerodynamic phenomena with the change of the distance between track centers may have on two trains passing by each other was predicted, and the stability of train operation was analyzed in order to review the distance between track centers suitable to Honam HSR trains. We conducted the parametric study of the effects of train wind on the running stability.

• Structural Engineering and Mechanics
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• v.6 no.7
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• pp.747-756
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• 1998

In this paper the influence of rotary inertia, shear and compressibility on the value of the critical force for the Beck's column is analyzed. The constitutive equation is of Engesser's type. As a result, the critical load parameter for which instability of flutter type occurs is calculated for several values of the column's parameters.

• Proceedings of the Korean Information Science Society Conference
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• 2011.06b
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• pp.385-387
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• 2011

본 논문은 철강 공정을 위한 로그서버의 구조를 설계하였다. 제안된 로그서버는 기존에 개발된 철강공정용 레벨 2 표준 미들웨어인 POSMOS 미들웨어의 특정 Agent 기능을 활용하여 독립적으로 구현됨으로써, 로그 활용을 위한 시스템 부하를 줄이고, 분산환경 아래에서의 통합적인 로그 수집이 가능하도록 설계 되었다. 본 로그 서버를 통한 로그 관리는 무정지 환경 아래의 철강 공정의 시스템의 안정성 확보를 위해 활용될 예정이다.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.33 no.2
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• pp.74-80
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• 2001

This study was carried out to manufacture microcapsules from natural aromatic essential oils by polymeric emulsification and to evaluate their properties using microscopical and electro-chemical analysis techniques. It was shown that aromatic essential oils (yuja, lavender, and peppermint) could be microcapsulated and their emulsion has a good stability and storage characteristics.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.34 no.5
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• pp.70-76
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• 2002

Ten years ago most papermakers were convinced that a system needs to be voluminous and heavy for controllability and stability. In order to improve grade changing dynamics, the author of this paper began developing a compact papermachine wet end. The results have proven that compactness is beneficial even more broadly. Quoting Voith$^1$the trend is now the opposite - the systematic collecting and direct feeding of the individual water flows back into the system". In its gasless form this is actually covered by a POM Technology Patent.tent.

• Journal of Navigation and Port Research
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• v.34 no.10
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• pp.807-815
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• 2010

This study analyzed the correlation between RFID acceptance intention and application, and as a result, extracted the technical stability, system quality and security of RFID as factors that affect the intention of receiving RFID in container terminal gate through preliminary research. This analysis was done on individuals engaged in container terminals which are in operation by adopting RFID in container terminal gate presently, and by distributing totally 255 copies of questionnaire survey, 248 copies were collected. As a result of statistical analysis of this study, the following conclusions were made: First, the technical stability of RFID acceptance in container terminal gate was not statistically significantly high. Second, the system quality and the security of RFID acceptance in container terminal gate were statistically significantly high. Finally, container terminal gate RFID technology acceptance intention was statistically significantly high in application performance.