• 한국재료학회지
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• 제17권12호
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• pp.676-681
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• 2007

According to progress rapidly digitalization, networked and mobilization of electronics industry, there are demands for being smaller, thinner, more light, and more efficient complex functions of electronic devices which are wireless devices, semi-conductors, packages and mobile devices. Therefore, the solder resist on a printed circuit board have been required with the high resolution and the eco-friendly materials in the surface treatments such as high heating process and coating process with electrolysis. In this study, the photoinitiator initiator and monomers of the solder resist were prepared with their contents for reducing the occurrence of the under-cut. We investigated the sample surface by UV/VIS spectrometer, FT-IR, OM after HASL and ENIG process. From our results, it is possible to get a high adhesion of resist with optimal contents between the photoinitiator initiator and monomers after surface treatments.

• Journal of Electrical Engineering and Technology
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• 제12권6호
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• pp.2089-2098
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• 2017

Microgrid is a convenient, reliable, and eco-friendly approach for the integration of Distributed Generation (DG) sources into the utility power systems. To date, AC microgrids have been the most common architecture, but DC microgrids are gaining an increasing interest owing to the provision of numerous benefits in comparison with AC ones. These benefits encompass higher reliability, power quality and transmission capacity, non-complex control as well as direct connection to some DG sources, loads and Energy Storage Systems (ESSs). In this paper, main challenges and available approaches for the protection of AC and DC microgrids are discussed. After description, analysis and classification of the existing schemes, some research directions including coordination between AC and DC protective devices as well as development of combined control and protection schemes for the realization of future hybrid AC/DC microgrids are pointed out.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2005년도 제31회 KOSCO SYMPOSIUM 논문집
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• pp.78-84
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• 2005

The development of eco-friendly low pressure carburizing system with high pressure gas quenching (LPC_GQ, 500kg/charge) led to new stage in the fundamental case-hardening treatments. This is due to its ability to provide tighter tolerances on the carburizing process with notable reductions in distortion of the carburized and hardened workpiece. This system is characteristics by high uniformity and reproducibility of heat treatment results, absence of an intergranular oxidation layer, carburizing of complex shapes, reduced cycle time, low operating costs, simplified production, eliminate post washing, and reduced grinding costs.

• 열처리공학회지
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• 제19권5호
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• pp.262-269
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• 2006

The development of eco-friendly low pressure carburizing system with high pressure gas quenching(LPC-GQ, 500kg/charge) led to new stage in the fundamental case-hardening treatments. This is due to its ability to provide tighter tolerances on the carburizing process with notable reductions in distortion of the carburized and hardened workpiece. This system is characteristics by high uniformity and reproducibility of heat treatment results, absence of an intergranular oxidation layer, carburizing of complex shapes, reduced cycle time, low operating costs, simplified production, eliminate post washing, and reduced grinding costs.

• Journal of Industrial and Engineering Chemistry
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• 제68권
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• pp.6-13
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• 2018

Well-modified amino-appended ${\beta}$-cyclodextrin ($AA-{\beta}-CD$) with an amino group at the primary face of the ${\beta}-CD$ was synthesized and used in the catalytic synthesis of chromeno pyrimido[1,2-b]indazol as supramolecular catalysts in water for the first time. $AA-{\beta}-CD$ was characterized by FT-IR, NMR, MALDI-TOF mass spectrometry, and SEM analysis. A possible reaction mechanism featuring molecular complexation was suggested based on 2D NMR (ROESY) spectroscopy, FE-SEM, DSC, and FT-IR. Advantages such as operational simplicity, recyclability of the catalysts, and accessibility in aqueous medium render this protocol eco-friendly.

• KIEAE Journal
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• 제11권1호
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• pp.29-38
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• 2011

This study suggested practical application of climate design on apartment complex with the focus on the use of Cold Air Flow and green building design method. The domestic research on the wind path analysis has been associated since the early 21th century in urban planning and site planning, this initiative study aimed to mitigate the urban heat island effect and to promote the sustainable urban development. It is, however, mostly focused on the flow analysis and heat flow in the urban context, due to the poor application of the wind path analysis in actual planning and design. Special attention is paid to the possibilities of identifying and developing the application methods in relation to Cold Air Flow and building design. This study examined these relations and suggested some trenchant approach to a more comprehensive and efficient use of the wind flow analysis in climate design.

• 한국주거학회논문집
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• 제21권5호
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• pp.13-22
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• 2010

This study has the purpose to reveal the differences of residents' using behaviors of living facilities at 3 complexes. The physical characteristics of the complexes have been investigated by a literature study and field survey. In addition, questionnaires were answered by residents on living facilities using behavior on community environment. The tools of analysis are frequency, percentage, and cross tabulation using SPSS WIN 12.0 program. Followings are the results of the study. 1) The developmental concept of 3 complexes maintained its initial identity. (1) The residence-oriented complex, having wider residential space, had better downtown access and more convenient facilities for daily life. (2) The residence-government mixed complex, constructed with an eco-friendly concept, had wider green and public service space and good downtown access but on the other hand, had less convenience facilities because of a short period from construction. (3) The residence-industry mixed complex, located in sub-urbanity and conceding more land for industries, had poor access to downtown but had more convenient facilities for workers' use. 2) The most frequently visited convenience facilities were shopping facilities, large or small, and banks, and activities were commonly done in the complex or adjacent area. This means it is recommended that the developer of the new complex locate convenience facilities in multi-core concentration types or street types rather than one-core concentration types.

• 대한토목학회논문집
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• 제35권4호
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• pp.987-996
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• 2015

최근 환경부의 조사결과에 의하면 대규모 종합병원 대학병원(58개소)의 실내 공기질이 유지기준을 초과한 것으로 나타났다. 내부 공기질은 물론, 병원 규모의 증가와 병원 건축물 대형화에 따른 친환경 건축물 설계와 저탄소 녹색 설계의 필요성이 절실히 요구되고 있는 상황이다. 특히 각 의료기관의 건축물에서 발생되는 이산화탄소, 발열, 쓰레기, 폐에너지, 발전소 배열, 하수열 등의 증가로 인해 병원 환자를 비롯한 병원 고객의 건강에 많은 문제점을 가져다주고 있다. 따라서 본 연구는 대규모 의료 단지에 건설되는 각각의 건축물이 가지는 의료기관으로써의 특성을 고려한 저탄소 녹색 친환경 건축설계에 도입되어야 하는 기술 개발과 각 의료 건축물 간의 유기적 관계를 고려한 녹색 친환경 건축디자인 기술을 융합적으로 개발하는 것을 연구목표로 한다.

• 전력전자학회논문지
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• 제15권3호
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• pp.188-198
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• 2010

최근들어, 전기이중층 커패시터 등의 친환경 전력저장장치의 수요가 증가하면서, 이를 위한 양방향 충/방전기의 수요 또한 증가하고 있다. 그러나, 기존의 상용화된 아날로그 제어기를 사용하는 DC-DC 컨버터를 충 방전기로 사용하게 되면, 충/방전 레퍼런스를 제공하는 상위 디지털 제어기와 별도로 아날로그 제어기를 제작해야 하는 문제가 있고, 회로가 복잡해지며, 모드전환 시 과도응답이 좋지 않다. 이에 대한 대안으로 단일 디지털 제어기를 사용하게 되면 쉽게 구현 가능한 설계방식을 이용하여 양방향 시스템의 성능을 향상 시킬 수 있다. 본 논문에서는 단일 회로 단 양방향 벅-부스트 컨버터에 전기이중층 콘덴서를 이용한 친환경 전력저장장치의 양방향 충/방전 시스템을 구현하고, DSP(TI사 TMS320F28335)를 이용한 디지털 제어기를 적용하였다. MATLAB simulink를 이용하여 모의실험을 수행하였고, 하드웨어를 구성하여 실험한 결과, 모의실험과 마찬가지로 양방향 시스템의 응답특성이 개선되었음을 보여주었다.

• 한국위험물학회지
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• 제6권2호
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• pp.77-86
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• 2018

Interest in renewable energy is increasing for eco-friendly use of energy, and fuel cells are being used in various ways such as houses and buildings as power generation methods that have low emissions such as $NO_X$ and $CO_2$. As the supply of fuel cells expands, more and more boilers are installed in the existing buildings, but safety management is not being performed properly. Therefore, in this study, a prior study was conducted on the status of fuel cell-boiler complex installation and related criteria, and the risk factors were analyzed according to the installation environment and structure. Based on these standards, the safety performance of the fuel cell-boiler combined installation is assessed by conducting a demonstration using the starting product of the simulated operation to derive the installation criteria (proposal) for the fuel cell-boiler combined installation. The installation criteria (proposal) include the construction and connection method of the piping according to the fuel cell-boiler complex installation.