• KIPE Magazine
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• v.14 no.4
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• pp.23-27
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• 2009

자동차 산업의 공통된 최대 이슈는 환경, 안전, 에너지, 편의이다. 이러한 시대적 요구에 따라 자동차 메이커들은 대응 방안 마련은 물론 시장 주도를 위한 기술개발 등 다양한 노력을 하고 있으며, 전장부품과 센서 등 최첨단 하이테크 기술과 플라스틱 , 나노, 하이브리드 소재 등이 적용된 다양한 부품들을 자동차에 적용시키고 있다. 또한수소연료전지, 바이오디젤, 태양광, 전기 등 석유 대체 에너지를 적용한 차세대 연료 자동차들이 전세계 모터쇼 등 전시회에 출품되어 세계의 이 목을 집중시키고 있으며 , 이미 일본과 미국시장을 중심으로 하이브리드 전기 자동차(HEV) 및 수소연료전지 자동차 (FCEV) 시장이 확대대고 있는 실증이다 따라서 국내에서도 그런카에 대한 관심도가 증가하고 있고 일부에서는 개발에 박차를 가하고 있다. 이에 그린카에 대한 간단한 구조와 최근 연구동향에 대해서 기술하고자 한다.

• Proceedings of the KSEE Conference
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• 2008.10a
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• pp.119-127
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• 2008

불꽃놀이는 한국명 연화(煙火), 중국명 폭죽(爆竹), 일본명 하나비(花火), 영어명 파이어웍스 디스플레이(Fireworks display) 표기되며 화약류를 연소 폭발시켜서 빛, 소리, 형태, 연기, 연막, 시간지연, 운동에너지 등을 조합하여 예술적인 감각을 연출시키는 공학으로써 공예술학으로 불랴는 일종의 예술작품이다. 우리나라의 연화기술은 세계적이다. 1980년대에 개발이 완료되었고, 1990년대에 완숙단계흘 거쳐 향후 2010년 이후에는 환경안전을 고려한 최첨단 나노 생명공학으로 발전하여야 할 것이다. 즐거운 불꽃축제 후에 환경오염방지 대책과 비상체제 운영능력, 저장소관리, 불발탄 및 폐기물처리, 시민의식 향상 등이 더욱 요망된다. 본 논문은 올해 제4회를 맞는 부산불꽃축제를 중심으로 현황 및 발전방향과 개선안을 제시하였다.

• Proceedings of the Korea Information Processing Society Conference
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• 2012.04a
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• pp.425-428
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• 2012

본 논문에서는 터널 내 유고 상황을 실시간으로 빠르게 감지하여 터널 관리자에게 상황을 전달하여 터널의 안전한 운영에 도움을 줄 수 있는 컴퓨터 비전을 이용한 터널 유고감지 시스템을 제안하였다. 제안한 시스템은 관리자, 서버, 영상 검지기로 구성되며 영상 검지기의 경우 객체를 추출하기 위하여 배경차이법을 사용하였으며, 터널 내에서 발생하는 조명의 변화, 입 출입구의 조명의 영향, 카메라의 프리컬링 잡음의 영향을 최소화하였으며, 터널 내에서 발생할 수 있는 정지물체, 차량 외 통행, 연기, 역주행, 정체 지체의 유고 상황을 감지하는 방법을 개발하였다. 제안한 시스템을 전남 여수의 마래터널 및 엑스포터널, 전북 임실의 운암터널에서 실험한 결과 터널 내에서 발생하는 유고 상황을 감지하였다.

• Design & Manufacturing
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• v.13 no.1
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• pp.42-47
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• 2019

Nucleate boiling heat transfer is one of the most important phenomenon in the various industries. Especially, critical heat flux (CHF) refers to the upper limit of the pool boiling heat transfer region. Therefore, many researchers have found that CHF can be significantly increased by adding very small amounts of nanoparticles. In this study, the CHF and heat transfer coefficient were tested under the pool boiling state using copper and multi wall carbon nanotube nanoparticles. The results showed that two different types of nanoparticles deposited on the surface of two specimens made of the same material increased the heat flux in the nanoparticles with high conductivity, and there was no difference in the critical heat flux when the same material nanoparticles were deposited on the two different specimen surfaces.

• Journal of the Korean Society of Propulsion Engineers
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• v.20 no.2
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• pp.18-23
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• 2016

Self-assembly of organic molecules is formed spontaneously on surfaces by electrostatic interaction with substrate. This research has shown that the self-assembly improves safety and handling tractability of high-energetic materials (HEMs). According to the recent study, control of the specific crystal size for reducing the internal defects is mightily important, because the internal defects are a factor in unstability of HEMs. In turn, we performed self-assembly of organic molecules and HEMs by using nano-sized HEMs, which were produced by drowing-out or milling/crystallization. Surface modification efficiency was decided by size distribution, zeta-potential, friction sensitivity and electrostatic charge.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.4
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• pp.2027-2036
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• 2013

Comparison of removal performance between reverse osmosis(RO), nanofiltration(NF), electrocoagulation(EC) and electroadsorption(EA) for removal of nitrate and fluoride often exceeded the limits of water quality in small water treatment plants. Removals of nitrate and fluoride were 72-92% and 74-85% in RO, 5-15% and 1% in NF, 99% and 44% in EA equipped with MWCNT coated electrodes, 82% and 77% in EA equipped with Cu-MWCNT electrodes, and 11-46% and 69-99% in EC. Consequently, high removals of both ions were anticipated in RO. Effective removal of both ions are possible for EC, but great production of sludge is a big burden. EA equipped with the MWCNT electrodes showed a great fluctuation in removal efficiency, and electrode stability should be upgraded.

• Journal of the Korean Society of Radiology
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• v.9 no.3
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• pp.131-137
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• 2015

The purpose of this study is to warm up the conventional X-ray table by inventing and design for X-ray table with an attached heating device using less unloaded X-ray, CNT (carbon nano tube) heating element. Configuration of the product design for adhesive carbon heating element X-ray is composed of a conventional X-ray table, carbon nano tube planar heating element, an electrode line, flame resisting protective film, and the bottom film. Characteristics and advantages of this invented product is to provide gentle feeling, the sense of security, and eliminating anxiety to the patient wearing a patient gown and feel the cool air while receiving the test. Thus we are strongly recommend to use this device in the clinical situation.

• Journal of the Korean Magnetics Society
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• v.16 no.6
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• pp.293-299
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• 2006

Magnetic nanoparticles were prepared by thermal decomposition and adsorbed with lecithin by applying ultrasonic. The size and saturation magnetization of magnetic nanoparticles were observed with different lecithin concentration, and the maximum tolerated dose (HTD) and toxicity of magnetic fluid was investigated through a biological test. The thickness of lecithin-adsorption layer increased non-linearly with increasing amounts of added lecithin, and the desirable adsorption amount was observed in the lecithin concentration of 20%(w/v). The dispersibility and magnetic properties of lecithin-adsorbed magnetic nanoparticles were most excellent when the ultrasonic exposure time was 1.5h. Also, the maximum tolerated concentration with best cell viability was $32{\mu}g/ml$ in vitro test, and lecithin-adsorbed magnetic fluids improved the biocompatibility by 1.2 times compared with bare magnetite fluids in vivo.

• Analytical Science and Technology
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• v.19 no.6
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• pp.468-472
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• 2006

This paper was described that the preparation of polymetylmethacrylate (PMMA) microsphere and coating of vitamin C onto surface of the prepared PMMA microsphere for application of cosmetic materials. The PMMA microsphere with various sizes can be obtained by change of reaction condition such as reaction temperature and reaction time. The coating of vitamin C on the surface of PMMA microsphere by using cyclodextrin as binder can be achieved to 30 wt-% in water/ethanol mixture. The vitamin C coated with cyclodextrin was stabilized during 56 days at $40^{\circ}C$. The color of the coated Vitamin C was changed from white to dark yellow after 14 days at $40^{\circ}C$. The vitamin C coated with cyclodextrin on the surface of PMMA microsphere can be sufficiently used for cosmetic materials.

• Journal of the Korean Electrochemical Society
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• v.23 no.2
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• pp.25-38
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• 2020

Photoelectrochemical water splitting has been considered as the most promising technology for generating hydrogen energy. Transition metal dichalcogenide (TMD) compounds have currently attracted tremendous attention due to their outstanding ability towards the catalytic water-splitting hydrogen evolution reaction (HER). Herein, we report the synthesis method of various transition metal dichalcogenide including MoS₂, MoSe₂, WS₂, and WSe₂ nanosheets as excellent catalysts for solar-driven photoelectrochemical (PEC) hydrogen evolution. Photocathodes were fabricated by growing the nanosheets directly onto Si nanowire (NW) arrays, with a thickness of 20 nm. The metal ion layers were formed by soaking the metal chloride ethanol solution and subsequent sulfurization or selenization produced the transition metal chalcogenide. They all exhibit excellent PEC performance in 0.5 M H₂SO₄; the photocurrent reaches to 20 mA cm^-2 (at 0 V vs. RHE) and the onset potential is 0.2 V under AM1.5 condition. The quantum efficiency of hydrogen generation is avg. 90%. The stability of MoS₂ and MoSe₂ is 90% for 3h, which is higher than that (80%) of WS₂ and WSe₂. Detailed structure analysis using X-ray photoelectron spectroscopy for before/after HER reveals that the Si-WS₂ and Si-WSe₂ experience more oxidation of Si NWs than Si-MoS₂ and Si-MoSe₂. This can be explained by the less protection of Si NW surface by their flake shape morphology. The high catalytic activity of TMDs should be the main cause of this enhanced PEC performance, promising efficient water-splitting Si-based PEC cells.