• Corrosion Science and Technology
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• 제4권4호
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• pp.121-129
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• 2005

Basic design concept of the future steel structure requires environmental compatibility and maintenance free capability to minimize economic burdens. Recent trends in alloy design for advanced weathering steel include addition of various alloying elements which can enhance formation of stable and protective rust layer even in polluted urban and/or high $Cl^{-}$ environment. The effects of Ca, Ni, W, and Mo addition on the corrosion property of Ca-modified weathering steel were evaluated through a series of electrochemical tests (pH measurement and electrochemical impedance spectroscopy: EIS) and structural analysis on rust layer formed on the steel surface. Ca-containing inclusions of Ca-Al-Mn-O-S compound are formed if the amount of Ca addition is over 25 ppm. Steels with higher Ca content results in higher pH value for condensed water film formed on the steel surface, however, addition of Ni, W, and Mo does not affect pH value of the thin water film. The steels containing a high amount of Ca, Ni, W and Mo showed a dense and compact rust layer with enhanced amount of ${\alpha}-FeOOH$. Addition of Ni, W and Mo in Ca-modified weathering steel shows anion-selectivity and contributes to lower the permeability of $Cl^{-}$ ions. Effect of each alloying element on the formation of protective rust layer will be discussed in detail with respect to corrosion resistance.

• 항공우주기술
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• 제13권1호
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• pp.120-128
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• 2014

우주 탐사를 향한 인류의 도전은 이제 태양계 바깥으로 확대되고 있다. 2010년대 전후의 우주 탐사 무대는 달에서 벗어나 주로 화성, 금성, 그리고 소행성(Asteroids)이 되고 있다. 우주선이 지구에서 멀어 질수록 여러 가지 기술적인 도전을 받고 있는데 통신 프로토콜이 대표적인 하나이다. 본 논문에서는 심우주 탐사선과 통신을 위해서 국제적으로 사용되고 있는 통신 프로토콜 기술을 소프트웨어적인 측면에서 분석한 결과를 기술하였으며 이는 2017년에 한국으로는 최초로 발사되는 시험용 달 궤도선 개발에 중요한 참고 연구가 될 것으로 판단된다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집D
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• pp.939-944
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• 2001

For the application of simultaneous $DeSO_{2}\;&\;DeNO_{x}$ equipment using non-thermal plasma process to the industrial and power plants, the many types of plasma device and process were studied. The e-beam and pulsed plasma corona discharge process are outstanding for the study to apply commercial large-scale plant from among these. In this paper, non-thermal plasma of technical trends and the characteristics of system developed by Doosan heavy industries & construction Co., Ltd. are explained. We have researched pulsed plasma corona discharge process since 1994. At the basis of reasonable results for the pilot plant, we constructed the demonstration plant at a domestic coal-fired power plant in 1999, as the previous step for commercial use. In near future, enough information about designs and costs of commercial-size system will be obtained.

• 펄프종이기술
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• 제36권5호
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• pp.69-77
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• 2004

Degradations of pine, yellow poplar and sweet gum by two fungi, Pycnoporus cinnabarinus and Trichophyton rubrum LSK-27 were investigated. P. cinabarinus degraded pine block samples much faster than T rub rum LSK-27, whereas P. cinnabarinus and T rubrum LSK-27 degraded yellow poplar and sweet gum at almost the same rate. In an effort to get a better understanding of how fungi degrade lignin in wood, contents of various functional groups were analyzed. After three-months of degradation of pine flour by these fungi, the following changes were observed: an increase in condensed phenolic OH group and carboxylic acid group content, a decrease in the guaiacyl phenolic OH content, and little change of aliphatic OH group content. Further studies in the degradation of pine flour by P. cinnabarinus indicated that the increase in condensed phenolic OH group content and the decrease in guaiacyl phenolic OH group content occurred in the first month of the degradation. The changes of functional group contents in the degradation of unbleached softwood kraft pulp by P. cinnabarinus had the same trends as those in the degradation of pine flour. That is, structural alteration of lignin due to the kraft pulping process had little effect on how P. cinnabarinus degraded lignin.

• 항공우주산업기술동향
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• 제7권1호
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• pp.128-140
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• 2009

본 논문에서는 FAR Part 23에 따른 복합재 소형항공기 구조 인증시 복합재료의 인증활동에서 발생할 수 있는 기술적 문제점 또는 고려사항을 검토하고, 이에 대한 인증 신청자가 수행해야 할 것으로 예상되는 사항을 검토하였다. 본 논문은 복합재 인증시 발생하는 기술적 문제에 초점을 맞추어 규정과의 관계 및 인증 경험에 관련한 기술 적 문제를 설명하였다. 복합재 인증활동에 대한 개괄적 내용과 복합재 항공기 구조물의 인증에 유용한 지침과 참고자료를 제시하고 있다. 본 논문에 소개된 일반적인 인증에 관련한 내용은 모든 복합재료 구조에 대해 적용되어지지 않을 수 있으며, 비행 안전에 치명적이지 않는 2차 구조에 대해서는 적용되어지지 않을 수 있다.

• Journal of Electrical Engineering and Technology
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• 제10권4호
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• pp.1408-1414
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• 2015

The renewable energies such as photovoltaic power, wind power and biomass have grown to a greater extent as decarbonization techniques. The renewable energies are interconnected to power systems (or electrical grids) in order to increase benefits from economies of scale, and the extra attention is focused on the Grid Code. A grid code defines technical parameters that power plants must meet to ensure functions of power systems, and the grid code determined by considering power system characteristics is various across the country. Some TSO (Transmission System Operator) and ISO (Independent System Operator) have issued grid code for wind power and the special requirements for offshore wind farm. The main purpose of the above grid code is that wind farm in power systems has to act as the existing power plants. Therefore wind farm developer and wind turbine manufacturer have great difficulty in grasping and meeting grid code requirements. This paper presents the basic understanding for grid codes of developed countries in the wind power and trends of those technical requirements. Moreover, in grid code viewpoint, the active power control of wind power is also discussed in details.

• 대한화장품학회지
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• 제24권2호
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• pp.80-99
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• 1998

근래에 여성들의 사회진출, 외출기회의 증가 그리고 화장 연령의 저하 또는 고령화에 따라 메이크업 제품의 수요가 증가하고 있으며 더불어 색상도 그 어느 때보다 강조되고 있다. 이 때문에 화장품 회사들은 Color Trend등을 근거로 매 시즌 새로운 색상 및 정보를 제공하고 있다. 그러나 최근들어 메이크업 제품에 색상뿐 만 아니라 그의 기능, 부가가치가 더욱 거세게 요구되어지고 있다. 따라서 메이크업 제품의 기본기능에 새로운 기능들이 부가되어지는 Skin Care 개념의 경향이 급속히 이루어지고 있으며 시장에서도 여러 종류의 다양한 상품들이 제공되고 있다. 본 논문에서는 메이크업 제품의 전체적인 흐름 및 기술동향을 알아보고 메이크업 제품의 미래를 전망해 보고자 한다. 여기에 덧붙여 메이크업이 소비자에게 미치는 심리학적 측면도 고찰해 보기로 한다.

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 2011년도 춘계학술발표회 논문집
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• pp.235-241
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• 2011

Effects of thermal aging on color variations of various papers were evaluated. With thermal aging, most of papers showed a special trend in $a^*$-$b^*$ plane: $a^*$ (red-green) values of the samples were reduced at beginning and after a turning point it was increased while $b^*$ (blue-yellow) was kept increased (yellowing of paper). In case of filter paper which consists of chemical pulps, the changes in $a^*$ value was occurred late compared with other samples. In case of the copy paper with optical brightening agent, the turning point in $a^*$ was not observed while a constant increase in $b^*$ was observed. In case of color paper, no specific trends in $a^*$-$b^*$ were found.

• 복식
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• 제62권3호
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• pp.73-83
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• 2012

The purpose of this study is to contribute in developing guidebooks that can be used in the courses of needlework study by comparing and analyzing the contents and organizations of needlework-related teaching resources available at the present university and fashion-related educational institutions. This research could help us train technical human resources to be highly adaptable in industrial settings. The results of this study showed that the overall organization of contents is mostly divided into such categories as needlework kits, basic hand sewing, seam finishing, partial needlework and decorative needlework. The study results also indicated that such content organization must be considered in basic needlework/sewing processes and that each content needs to provide more various and detailed information by reflecting recent trends in design. Partial needlework has different applications in terms of interlining attachment, subsidiary materials, or sewing techniques; therefore, consistent descriptions and standard guidelines should be given according to what material is used and which design is planned. This study found that most teaching resources covered only needlework or sewing techniques without giving specific descriptions of types of materials, lining and interlining that can have great influence on sewing methods and instructions on how to use the materials. These findings suggest that the teaching resources need to add further technical instructions for the proper use of materials especially in response to the recent release of brand-new materials and sewing machines in the market.

• The Journal of Asian Finance, Economics and Business
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• 제7권9호
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• pp.561-572
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• 2020

Sustainable development - including tourism development - is the general trend of all economies. With the orientation to build and develop the tourism industry into a key economic sector and become a tourist center of the Southeast region, Vietnam, Ba Ria-Vung Tau Province is demanding a proper, rational, development policy, while ensuring the development and exploitation of immediate natural advantages, and ensuring long-term sustainable development. The objective of this study is to examine the factors and their trends in sustainable tourism development in Ba Ria-Vung Tau Province, Vietnam. Methods used include descriptive statistical analysis, exploratory factor analysis and regression analysis. Data was collected from the results of a survey of 550 domestic and foreign tourists visiting Ba Ria-Vung Tau. With the help of SPSS statistical software, 12 groups of factors affecting sustainable development were identified including: economy, society, environment, humanistic tourism resources, natural tourism resources, tourism human resources, tourism products and service, tourism quality, infrastructure, technical facilities, governmental management and group of criteria to evaluate sustainable tourism development. The research results show that there are four groups of factors that significantly affect sustainable tourism development in Ba Ria-Vung Tau. These are groups of factors: Society, Environment, Tourism products and service, and Technical facilities.