• Korea Information Processing Society Review
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• v.15 no.2
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• pp.123-132
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• 2008

그리드 기반의 e-Science 시스템을 실용화하여 세계 최고 수준의 국가적 첨단 공동 연구 장비의 활용도를 제고하고 e-Science 기반의 동시협업 연구가 가능한 차세대 연구 개발 환경 구축을 목적으로 국내 유일의 가속전압 1.3 MV의 초고전압투과전자현미경 (HVEM)을 이용한 전문연구 포털인 e-HVEM 포털을 개발하였다. 이는 웹 포탈 시스템에서 원격 제어 (Tele-HVEM), Nano-Bio 데이터베이스 및 계산 그리드 기반의 tomography 시스템 (G-Render)를 동시에 사용 할 수 있는 통합 연구 환경으로써 e-HVEM 포털 시스템에서 단순 장비 운용뿐만 아니라 실제연구 분석까지 활용할 수 있도록 하였다. 특히 본 연구에서는 HVEM으로부터 얻어진 일련의 화상 정보들에 대한 3차원 구조 복원을 위하여 그리드 연산 시스템을 도입함으로써 보다 빠른 시간에 원하는 최종 결과물을 얻을 수 있도록 구성하였다. 이로써 e-HVEM 포털은 다양한 국가 대형 연구 장비를 활용하여 시공간 개념을 넘어선 e-Science 공동 협업 시스템의 성공적인 모델로써 국내는 물론 국제적인 공동 연구를 수행할 수 있는 장비 활용 가상 실험실 구축의 실현 가능성을 시사한다.

• Transactions on Electrical and Electronic Materials
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• v.16 no.3
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• pp.135-138
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• 2015

A manganese dioxide (MnO₂) layer and zinc (Zn) layer are used as the cathode and the anode to develop filmtype manganese battery, in which a stack of a MnO₂ layer, gel electrolyte, and Zn layer are sandwiched between two plastic layers. This paper describes the chemical equation of swelling control upon the film-type manganese battery. We examined the reduction of hydrogen formation, by using calcium hydroxide Ca(OH)₂ as an additive in the electrolyte of film-type manganese battery. The phenomena or an effect of reduced hydrogen gas was proven by cyclic voltammogram, X-ray photoelectron spectra (XPS), and volume of hydrogen formation. The amount of H₂ gas generation in the presence of Ca²⁺ ion was reduced from 4.81 to 4.15 cc/g-zinc (14%), and the corrosion of zinc electrode in the electrolyte was strongly inhibited as time passed.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.30 no.3 s.47
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• pp.307-311
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• 2004

In cosmetics industry, we notice that the research should be focused on developing well-being related products such as SPA, esthetique, mass-customization, organics, naturals besides inner beauty and body shaping products. These well-being related products should satisfy customers' expectation about not only concern about health but also safety, reliability, and ethos about products. In that context, the systematic way for well-being related research in cosmetics should be carried out concerning anti-aging with fat-decom-position, vitamin, polyphenol, and organics. At the same time, there are several important factors in this research like augmenting efficacy, controlling skin-absorbency, skin-adaptability, forming, stabilization of activated com-ponents, improving sustainability, and developing new materials based on dermatologic and emotional science. It should be also emphasized that recent technologies such as bio-technology, nano-technology, and natural-material-technology are the cornerstones of developing well-being products.

• Bulletin of the Korean Chemical Society
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• v.34 no.5
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• pp.1435-1440
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• 2013

To investigate the influence of the carbon matrix on the electrochemical performance of Si/C composites, four types of Si/C composites were prepared using graphite, petroleum coke, pitch and sucrose as carbon precursors. A ball mill was used to prepare Si/C blends from graphite and petroleum coke, whereas a dispersion technique was used to fabricate Si/C composites where Si was embedded in disordered carbon matrix derived from pitch or sucrose. The Si/pitch-based carbon composite showed superior Si utilization (96% in the first cycle) and excellent cycle retention (70% after 40 cycles), which was attributed to the effective encapsulation of Si and the buffering effect of the surrounding carbon matrix on the silicon particles.

• Journal of the Society of Naval Architects of Korea
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• v.45 no.2
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• pp.144-150
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• 2008

Ships and offshore structures are exposed to wave and engine excitation loadings during navigation and cargo/ballasting operations. These excessive loads may cause damages to hull and may result loss of life the ship. Therefore, it is important to develop a system that allow accurate measurements of global hull loads. The objective of the study is developing a fiber optic monitoring system that is capable of monitoring, recording and warning of the vessel performance. A method for measurement of global loads on a vessel, using strain measurements from a network of fiber optic strain sensors and extensive finite-element analyses(FEA) with idealistic load cases, is presented. The method has been successfully validated on the idealized ship structure model with strain sensors.

• KSBB Journal
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• v.22 no.6
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• pp.387-392
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• 2007

Recently, microfluidic biochips for DNA microarray are providing a number of advantages such as, reduction in reagent volume, high-throughput parallel sample screening, automation of processing, and reduction in hybridization time. Particularly, the enhancement of target probe hybridization by decrease of hybridization time is an important aspect highlighting the advantage of microfluidic DNA microarray platform. Fundamental issues to overcome extremely slow diffusion-limited hybridization are based on physical, electrical or fluidic dynamical mixing technology. So far, there have been some reports on the enhancement of the hybridization with the microfluidic platforms. In this review, their principle, performance, and outreaching of the technology are overviewed and discussed for the implementation into many bio-applications.

• Journal of Microbiology and Biotechnology
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• v.16 no.4
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• pp.590-596
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• 2006

Clavulanic acid (CA) produced by Streptomyces clavuligerus is degraded during the bacterial cultivation. The degradation was examined in three different aspects, including physical, chemical, and enzymatic effects, in order to understand the degradation during the cultivation. The result showed that CA was unstable in the production medium containing ammonium salts and amino acids, owing to ammonium ions and amine groups. In addition, the degradation was not only due to instability of CA by metabolites and proteins, but also enzymes from S. clavuligerus such as $\beta-lactamase$ and penicillin-binding proteins. However, the degradation caused by these enzymes was not highly significant compared with the degradation during the cultivation, owing to irreversible reactions between CA and enzymes.

• Environmental Analysis Health and Toxicology
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• v.22 no.3
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• pp.189-196
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• 2007

[ $TiO_2$ ] is widely used because it is non-toxic. Recently, however, nanometer size $TiO_2$ particles (P-25) have been produced and used to increase the photo catalysis efficiency. Nanometer-sized $TiO_2$ is efficient, but due to its small size ($20{\sim}30\;nm$), it can flow into ecosystems and into cells. Thus, it may affect human health. Additionally, $TiO_2$ can produce a second contaminant, OH-radical, which is a health risk for all living organisms during photo degradation reaction. Hence, when nanometer-sized $TiO_2$ flows into natural streams and attaches to living organisms, it will create health risks. We investigated the biological toxicity of this condition in zebrafish embryos. We observed abnormal morphology, hatching rate, and measured the catalase activity to determine anti-oxidation at 100 post fertilization hours. Zebrafish were somewhat affected by $TiO_2$ nanometer sized particles under UV-A (a condition similar to sunlight). Powdered $TiO_2$ is toxic to the zebrafish fly. Even without light, $TiO_2$ particles attached to embryos and flies, having an effect on both.

• Journal of the Korean Magnetic Resonance Society
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• v.10 no.2
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• pp.141-154
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• 2006

A solid-state reaction of $V_2O_5$ with AlMCM-41 followed by calcinations generated $V^{5+}$ species in the mesoporous materials. Dehydration results in the formation of a vanadyl species, $VO^{2+}$, that can be characterized by electron spin resonance (ESR). The chemical environment of the vanadium centers in V-AlMCM-41 was investigated by XRD, EDX, diffuse reflectance UV-VIS, ESR, $^{29}Si,\;^{27}Al,\;and\;^{51}V$ NMR. It was found that the vanadium species on the wall surface and inside the wall of the hexagonal tubular wall of the V-AlMCM-41 were completely oxidized to tetrahedral $V^{5+}$ and transformed to square pyramidal by additional coordination to water molecules upon hydration. The oxidized $V^{5+}$ species on the wall surfaces and inside the wall were also reversibly reduced to $VO^{2+}$ species or lower valences by thermal process.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.11a
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• pp.528-528
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• 2007

Cu CMP widely has been using for the formation of multilevel metal interconnects by the Cu damascene process. And lower dielectric constant materials are required for the below 45nm technology node. As the dielectric constant of dielectric materials are smaller, the strength of dielectric materials become weaker. Therefore these materials are easily damaged by high down pressure during conventional CMP. Also, technical problems such as surface scratches, delamination, dishing and erosion are also occurred. In order to overcome these problems in CMP, the ECMP (electro-chemical mechanical planarization) has been introduced. In this process, abrasive free electrolyte, soft pad and low down force were used. The electrolyte is one of important factor to solve these problems. Also, additives are required to improve the removal rate, uniformity, surface roughness, defects, and so on. In this study, KOH and $NaNO_3$ based electrolytes were used for Cu ECMP and the electrochemical behavior was evaluated by the potentiostat. Also, the Cu surface was observed by SEM as a function of applied voltage and chemical concentration.