• Carbon letters
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• 제22권
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• pp.1-13
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• 2017

Porous materials play a vital role in science and technology. The ability to control their pore structures at the atomic, molecular, and nanometer scales enable interactions with atoms, ions and molecules to occur throughout the bulk of the material, for practical applications. Three-dimensional (3D) porous carbon-based materials (e.g., graphene aerogels/hydrogels, sponges and foams) made of graphene or graphene oxide-based networks have attracted considerable attention because they offer low density, high porosity, large surface area, excellent electrical conductivity and stable mechanical properties. Water pollution and associated environmental issues have become a hot topic in recent years. Rapid industrialization has led to a massive increase in the amount of wastewater that industries discharge into the environment. Water pollution is caused by oil spills, heavy metals, dyes, and organic compounds released by industry, as well as via unpredictable accidents. In addition, water pollution is also caused by radionuclides released by nuclear disasters or leakage. This review presents an overview of the state-of-the-art synthesis methodologies of 3D porous graphene materials and highlights their synthesis for environmental applications. The various synthetic methods used to prepare these 3D materials are discussed, particularly template-free self-assembly methods, and template-directed methods. Some key results are summarized, where 3D graphene materials have been used for the adsorption of dyes, heavy metals, and radioactive materials from polluted environments.

• 정보처리학회논문지:소프트웨어 및 데이터공학
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• 제7권8호
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• pp.307-324
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• 2018

최근 순환 신경 망(Recurrent Neural Networks)은 시간에 대한 의존성을 고려한 구조를 통해 순차 데이터(Sequential data)의 예측 문제 해결에서 각광받고 있다. 하지만 순차 데이터의 시간 스텝이 늘어남에 따라 발생하는 그라디언트 소실(Gradients vanishing)이 문제로 대두되었다. 이를 해결하기 위해 장단기 기억 모델(Long Short-Term Memory)이 제안되었지만, 많은 데이터를 저장하고 장기간 보존하는 데에 한계가 있다. 따라서 순환 신경망과 메모리 요소(Memory component)를 활용한 학습 모델인 메모리-증대 신경망(Memory-Augmented Neural Networks)에 대한 연구가 최근 활발히 진행되고 있다. 본 논문에서는 딥 러닝(Deep Learning) 분야의 화두로 떠오른 메모리-증대 신경망 주요 모델들의 구조와 특징을 열거하고, 이를 활용한 최신 기법들과 향후 연구 방향을 제시한다.

• 복식
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• 제66권3호
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• pp.107-120
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• 2016

This study examines functions in traditional Korean special costumes in accordance with the climatic factors of the Korean peninsula. The study focused on clothes worn by commoners during the Joseon dynasty. Climate change has been a major global issue in recent times, and it has been a hot topic in social, cultural, scientific, economic, and industrial communities. Studies have been conducted regarding the rapidly changing climate, and finding ways to cope with unusual temperatures. This thesis studies the development of special costumes in preparation for unusual climates, and requirements of the costume in accordance with the climatic factors, as well as the direction of its development. Its biggest significance lies in collecting and organizing the research data on special costume studies, and on costumes of the commoners, which have been fairly insufficient up to this point. After the Little Ice Age, the Joseon Dynasty period faced poor external environment due to unusual temperatures. The results of studying the costumes of the commoners are as follows: The climate of the Korean peninsula displayed different characteristics depending on the season, so the form, material, and appearance of the seasonal clothing items showed clear differences, and the difference in the crops cultivated according to the climate led to difference in material and material preference shown in the costumes. This meant that costumes differed based on region. In addition, difference in social hierarchy, regulations on costume according to class, and farming oriented social background during the period of Joseon dynasty slowed the development of costumes of commoners, but appears to have had a positive effect on the development of special costumes. We anticipate more succeeding studies on costumes of the commoners and special costumes in the future. We hope more costumes that can wisely respond to the approaching changes in temperature in the Korean peninsula can be designed via modernization of traditional Korean special costumes.

• 한국해양공학회지
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• 제25권1호
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• pp.32-38
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• 2011

Galvanized steel has gone through a chemical process to keep it from corroding. The steel gets coated in layers of zinc because rust will not attack this protective metal. For countless outdoor, marine, or industrial applications, galvanized steel is an essential fabrication component. The reduction of the corrosion rate of zinc is an important topic. In the past, a very popular way to reduce the corrosion rate of zinc was to use chemical conversion layers based on $Cr^{+6}$. However, a significant problem that has arisen is that the use of chromium salts is now restricted because of environmental protection legislation. Therefore, it is very important to develop new zinc surface treatments that are environmentally friendly to improve the corrosion resistance of zinc and adhesion with a final organic protective layer. In this study, a Urethane solution (only Urethane 20 wt.%; S-700) and an organic/inorganic solution with Si (Si polysilicate 10 wt.% + Urethane 10 wt.%; LRO-317) are used. Based on the salt spray test of 72 h, S-700 and LRO-317 had a superior effect for the corrosion resistance on EGI and HDGI, respectively.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2009년도 춘계학술발표대회 논문집
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• pp.184-189
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• 2009

In order to improve the operation of energy systems, it is necessary for the urban communities to have reliable optimization routines, both computerized and manual, implemented in their organizations. However, before a production plan for the energy system units can be constructed, a prediction of the energy systems first needs to be determined. So, several methodologies have been proposed for energy demand prediction, but due to uncertainties in urban community, many of them will fail in practice. The main topic of this paper has been the development of a method for energy demand prediction at urban community. Energy demand prediction is important input parameters to plan for the energy planing. This paper presents a energy demand prediction method which estimates heat and electricity for various building categories. The method has been based on artificial neural networks(ANN). The advantage of ANN with respect to the other method is their ability of modeling a multivariable problem given by the complex relationships between the variables. Also, the ANN can extract the relationships among these variables by means of learning with training data. In this paper, the ANN have been applied in oder to correlate weather conditions, calendar data, schedules, etc. Space heating, cooling, hot water and HVAC electricity can be predicted using this method. This method can produce 10% of errors hourly load profile from individual building to urban community.

• 한국전자거래학회지
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• 제13권4호
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• pp.125-144
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• 2008

최근 기업 경영의 관심은 환경 변화에 신속히 대응하고, 지속적으로 성장하기 위한 경쟁력 확보에 있다. IT(Information Technology)가 이러한 기업의 경쟁력을 강화하는 핵심 동인으로서 주요한 역할을 담당하면서, 경영과 IT의 연계, IT를 통한 제품 및 서비스의 혁신 등이 최근 주요한 화두로 자리 잡았다. 그러나 기존의 국내외 정보화 평가지수 및 관련 연구들은 IT 자체의 양적인 구축과 활용수준, 그 경제성 효과에 초점이 맞추어져 있어서, IT가 경영 혁신을 지원하고 주도하는 수준에 대한 평가가 미흡한 것이 사실이다. 그러므로 본 연구에서는 차세대 정보화수준 평가 시스템이 갖추어야 하는 요건을 정의하고, 이를 기반으로 한 평가영역과 평가항목을 개발한다. 또한, 기업 정보화의 다양한 특성유형을 설명할 수 있는 다차원의 해석 방식을 제시한다. 본 연구를 통해 개발된 평가시스템 EIII 2.0은 국내 금융 업종의 2개 기업을 대상으로 한 파일럿 테스트로 실용성을 검증하였다.

• Nuclear Engineering and Technology
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• 제52권7호
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• pp.1517-1523
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• 2020

The widely used medical isotope technetium-99 m (^99mTc) is a daughter of Molybdenum-99 (⁹⁹Mo), which is mainly produced using dedicated research reactors from the nuclear fission of uranium-235 (²³⁵U). ^99mTc has been used for several decades, which covers about 80% of the all the nuclear diagnostics procedures. Recently, the instability of the supply has become an important topic throughout the international radioisotope communities. The aging of major ⁹⁹Mo production reactors has also caused frequent shutdowns. It has triggered movements to establish new research reactors for ⁹⁹Mo production, as well as the development of various ⁹⁹Mo production technologies. In this context, a new research reactor project was launched in 2012 in Korea. At the same time, the development of fission-based ⁹⁹Mo production process was initiated by Korea Atomic Energy Research Institute (KAERI) in 2012 in order to be implemented by the new research reactor. The KAERI process is based on the caustic dissolution of plate-type LEU (low enriched uranium) dispersion targets, followed by the separation and purification using a series of columns. The development of proper waste treatment technologies for the gaseous, liquid, and solid radioactive wastes also took place. The first stage of this process development was completed in 2018. In this paper, the results of the hot test production of fission ⁹⁹Mo using HANARO, KAERI's 30 MW research reactor, was described.

• 한국융합학회논문지
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• 제11권11호
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• pp.135-145
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• 2020

4차 산업혁명시대에 진입하면서 디자인은 초연결사회의 다매체간의 융합으로 진행되고 있다. 특히 전통문화와 브랜드의 디자인 이념과의 융합은 디자인 영역에서 큰 화제로 다뤄지고 있다. 이러한 지점에서 중국의 선사상과 디자인이 융합된 무인양품의 디자인은 매우 주목할 만하다. 중국의 선(禅)사상은 노자와 장자의 사상을 흡수하여, "무상(無相)의 모습, 무주(無住)의 근본, 무념(無念)의 종지"를 목적으로 삼아 유가철학과 도가철학, 그리고 미학이 공존하는 독특한 사상 체계를 형성하였다. 그렇다면 전통문화로서 선사상은 무인양품의 디자인 속에서 어떤 모습으로 나타고 있는가? 본 연구는 이러한 문제의식에서 출발해 중국 선사상이 반영된 무인양품의 디자인 특징을 살펴보았다. 그 결과, 중국의 선사상을 지닌 무인양품의 디자인 특징은 미니멀리즘 조형, 단일적 색채, 생태적 소재, 인간성 체험의 네 가지로 귀결됨을 확인할 수 있었다.

• 세라미스트
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• 제22권3호
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• pp.281-300
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• 2019

Surface enhanced Raman scattering (SERS) was first discovered in 1974 by an unexpected Raman signal increase from Pyridine adsorbed on rough Ag electrode surfaces by the M. Fleishmann group. M. Moskovits group suggested that this phenomenon could be caused by surface plasmon resonance (SPR), which is a collective oscillation of free electrons at the surface of metal nanostructures by an external light source. After about 40 years, the SERS study has attracted great attention as a biomolecule analysis technology, and more than 2500 new papers and 500 review papers related to SERS topic have been published each year in recently. The advantages of biomaterials analysis using SERS are as follows; ① Molecular level analysis is possible based on unique fingerprint information of biomolecule, ② There is no photo-bleaching effect of the Raman reporters, allowing long-term monitoring of biomaterials compared to fluorescence microscopy, ③ SERS peak bandwidth is approximately 10 to 100 times narrower than fluorescence emission from organic phosphor or quantum dot, resulting in higher analysis accuracy, ④ Single excitation wavelength allows analysis of various biomaterials, ⑤ By utilizing near-infrared (NIR) SERS-activated nanostructures and NIR excitation lasers, auto-fluorescence noise in the visible wavelength range can be avoided from in vivo experiment and light damage in living cells can be minimized compared to visible lasers, ⑥ The weak Raman signal of the water molecule makes it easy to analyze biomaterials in aqueous solutions. For this reason, SERS is attracting attention as a next-generation non-invasive medical diagnostic device as well as substance analysis. In this review, the principles of SERS and various biomaterial analysis principles using SERS analysis will be introduced through recent research papers.

• 한국주거학회:학술대회논문집
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• 한국주거학회 2009년 춘계학술발표대회 논문집
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• pp.161-166
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• 2009

Resident and user participation has been emerging as a hot topic and has been predicted to be popular and general in urban planning and regeneration, specially in housing regeneration in future. Also the number of the resident who are willing to participate in planning and regeneration process is expected to increase drastically as democratic and diverse society get matured. To enable a wide range of residents in planning process within a very limited time, effective and efficient communication tools need to be prepared. The purpose of study is to develop a set of tools for facilitating residents to participate actively in the process of exploring, consulting and decision making process in the street and regeneration. A realistic and feasible testbed site was decided. Developed tools were first, educational contents to empower resident capability to select a better design, second, three dimensional scaled model of existing site, third, floorplan and elevation of design alternative, forth, computer simulation images of both 3D & sketch-up for comparing wall heights and their effect. fifth, Two workshops among professionals and one workshop with residents were carried. Through the workshop, guidelines of developing communication tool for facilitating resident participation was developed. Its usage was summarized in both in further analog and digital tool.