• Proceedings of the Korean Society of Disaster Information Conference
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• 2017.11a
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• pp.271-272
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• 2017

자외선 에너지는 미생물의 DNA를 파괴함으로써 살균 효과를 일으킨다. 자외선 방사로 공기 중 미생물에 대하여 높은 살균력을 얻기 위해선 강한 자외선 강도와, 흐르는 공기가 충분한 시간 동안 강한 자외선에 노출되어야 하므로 균일한 자외선 방사는 매우 중요하다. 기존 UV살균 시스템은 강한 자외선 에너지와 공기의 빠른 이동에 필요한 UV방사의 균일성을 제공하지 않았다. 하지만 HDS의 BioProtector 제품에 사용된 Advanced UV System(AUVS) 반사 캐비티 기술은 매우 높은 수준의 균일성을 생성함으로써 이 문제에 대한 해결책을 제공하며, 미생물 살균에 가장 효과적인 UV파장을 사용하여 6 LOG KILL (100만마리의 미생물 투입시 1마리 이하생존) 수준의 살균 효과를 만들었다.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.47 no.12
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• pp.97-103
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• 2010

In this paper, worldwide standards and regulations on in-band/out-of-band emission characteristics of DTV broadcasting equipments are reviewed, and emission mask requirements of several equipment types are analyzed. Out-of-band emission mask draft suitable for DTV repeater is proposed and its usefulness is evaluated and verified in the experiments. Using the proposed standard, small-sized and cost effective DTV repeater can be implemented to broaden DTV broadcasting coverage for digital switchover.

• The Journal of the Acoustical Society of Korea
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• v.28 no.4
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• pp.299-307
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• 2009

In this study, the acoustical properties of micro-speaker had been studied as a function of diaphragm patterns. The diaphragm was divided into two sections, such as edge and dome sides. The pattern change at each side affected the tensile strength of diaphragm. As a result, the resonance frequency was varied with the change. With increasing the number of pattern at the edge side, it was increased at the first, but it reversed to the exponential decrease of that. It increased due to the increase of tensile strength to be caused by using "U" type of drill and whirlwind pattern, and decreasing of drill angle at the edge side. However, it was decreased due to the decrease of tensile strength to be by increasing the number of radiation pattern and dome hight, and decreasing the dome radius at the dome side.

• Proceedings of the Korean Fiber Society Conference
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• 1997.10a
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• pp.404-410
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• 1997

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2016.05a
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• pp.333-334
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• 2016

• Composites Research
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• v.23 no.3
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• pp.43-49
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• 2010

Basaltic fiber was prepared by continuous spinning process from Jeju Pyosun raw basalt materials. First, for confirming the melting characterization of basalt, basalt raw material put into Pt crucible and melted up to $1550^{\circ}C$ then quenched by dropping it into water. After quenching, the optimum fiber spinning conditions were investigated by measurement and analysis of XRD, TMA, high temperature viscosity, high temperature conductivity and high temperature microscope. The optimum spinning temperature and viscosity for preparation of continuous filament fiber were $1264^{\circ}C$ and $10^{2.8}$ poise at $1264^{\circ}C$, respectively. Properties of prepared spinning fiber were confirmed by tensile strength, FE-SEM, heat resisting test and others. The tensile strength of fiber prepared by spinning conditions of the bushing temperature $1240^{\circ}C$ and winder speed 4600rpm was 3660MPa.

• Proceedings of the Korean Nuclear Society Conference
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• 1998.05b
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• pp.385-390
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• 1998

방사성 페이온교환수지 아스팔트고화체를 처분장 등지에서 장기간 저장시 안전성 확보를 위하여 물리적 강도가 높고 고화체내에서 방사성핵종의 침출저항성 및 처리시 감용의 효과가 우수한 고화체 연구가 필요하게 되었다. 실험에 사용된 이온교환수지는 입상형 양이온 교환수지를 대상으로 하였으며 고화매질로서는 도로포장용으로 생산되는 직류아스팔트 60/70을 사용하였다. 고화보조제는 방사성 고체패기물 포장시 사용되어 폐기물로 발생되는 페폴리에틸렌(폐PE) 필름을 사용하였다. 실험결과 고화체의 형태안정성은 PE 함유량이 10 wt% 이상일 때 고화체 형태를 그대로 유지할 수 있으며 압축강도는 414 kPa(60 psi) 이상을 나타내었다. 최적의 운전조건은 이온교환수지, PE 함유량이 건조기준으로 각각 30~50 wt%, 10~25 wt% 이며, 고화온도는 170~20$0^{\circ}C$이다. 고화체의 침출특성은 확산 (diffusion) 으로 해석이 가능하며, 유효확산계수(De)는 Cs, Co의 경우 각각 1.621$\times$$10^{-7}$, 1.186$\times$$10^{-9}$ $\textrm{cm}^2$/day로 나타나고, Leachablity index는 각각 11.7, 13.8로 미국 원자력위원회 (NRC)가 요구하는 기준값 6보다 훨씬 높게 나타났다.

• Proceedings of the Korean Fiber Society Conference
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• 2003.04a
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• pp.95-97
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• 2003

전기방사는 submicron 이하 크기의 섬유를 부직포형태인 3차원으로 적층된 웹상으로 얻을 수 있는 방법으로 최근 많은 연구가 되고 있다[1-3]. 전통적인 방사방법인 용융방사와 melt blown 방사 방법으로 제조되는 피치계 탄소섬유는 우수한 방사성을 갖는 프리커서 피치를 이용해야 하고 이러한 방법으로 제조되는 탄소섬유나 활성탄소 섬유는 주로 직경 10-15 um 내외의 것이 대부분이어서 상대적으로 직경이 크기 때문에 굽힘 강도가 낮아 압축가공이 취약하다. (중략)

• Journal of The Korean Radiological Technologist Association
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• v.28 no.1
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• pp.299-300
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• 2002

• KSCE Journal of Civil and Environmental Engineering Research
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• v.40 no.2
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• pp.177-182
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• 2020

In this study, the effect of nanofibers in cement pastes on the compressive and tensile strength of hardened cement pastes was studied. Two types of nanofibers, nylon 66 nanofibers and carbon nanotube-nylon 66 hybrid nanofibers, were manufactured by electrospinning methodology and mixed in cement powder respectively. The specimens for experiments were prepared by water to cement ratio of 0.5 and cured in water for 28 days. The effect of nanofibers on the increase of the compressive and tensile strength were confirmed by the experimental results. The well-linking effect of nanofibers in the microstructure of the hardened cement pastes has been found by scanning electron microscope (SEM) analysis and well-explained for the increase in mechanical strength. Besides, field emission transmission electron microscope (FE-TEM) analysis and thermal gravimetric analysis (TGA) have also been conducted to analyze the properties of nanofibers as well as the microstructure of the hardened modified cement pastes.