• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2007.11a
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• pp.41-42
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• 2007

• Journal of the Korean Society of Radiology
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• v.12 no.3
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• pp.305-312
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• 2018

A dry and wet wipe test for radioisotope leakage checking was conducted by fixing the radioisotope $^{14}C$ to the glass surface and used for observing the transfer factor and surface shape of the test paper through wipe test. The dry wipe test showed that transfer factor in the tissue paper was twice as high as in the paper filter, and the wet wipe test showed that transfer factor in the paper filter paper was three times higher than the tissue paper. Although paper filters are general choice for leakage checking, it has been shown that tissue paper can be an alternative in the dry wipe test.

• Composites Research
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• v.26 no.2
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• pp.123-128
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• 2013

The PVDF (polyvinylidene fluoride) fibers were prepared using the wet spinning processing. To improve ${\beta}$-phase crystalline which closely related piezoelectric property PVDF wet spun fibers conducted post treatment. Post treatment is consisted of heat stretching and annealing process. The heat stretching and annealing conditions were controlled by changing temperature between glass transition temperature and melting temperature. From these experimental data, the resulting crystal structure of the ${\beta}$-phase crystalline was confirmed by FT-IR and XRD experiments. From these analysis results, optimum stretching and annealing conditions of the wet spun PVDF fibers were founded to increase high ${\beta}$-phase crystalline. Furthermore results showed that thermal processing had a direct effect on modifying the crystalline microstructure and also confirmed that heat stretching and annealing could increase the degree of crystallinity and ${\beta}$-phase crystalline. Finally, piezoelectric constant ($d_{11}$) of the post heat treated PVDF fibers reinforced composite were measured to investigate the feasibility for the sensing materials.

• Proceedings of the Korean Fiber Society Conference
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• 2003.04a
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• pp.382-383
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• 2003

정전방사란 고분자 용융체 또는 고분자 용액에 전기적인 힘을 이용하여 나노크기의 직경을 가지는 섬유를 제조하는 공정이다. 정전방사에서는 전기적인 힘을 이용하여 기존의 건식 및 습식 방사기술로서 섬유화가 어려웠던 재료들을 간단한 방법으로 섬유화 시킬 수 있으며, 매우 적은 양으로 방사가 불가능했던 재료들에 대해서도 방사가 가능하며, 부직포 형태로 제조된다는 특징이 있다. 본 연구에서는 PVdF계 공중합체 폴리머로서 PVdF-HFP 공중합체를 아세톤 용매에 다양한 농도로 용해시켜 고분자 용액을 제조한 후, 정전방사에 의한 나노크기의 직경의 섬유를 제조하는 방사조건을 고찰하였다. (중략)

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2004.06a
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• pp.237-237
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• 2004

사용후핵연료를 건식처리하여 핵연료성 물질을 제거하고 또한 장반감기 핵종을 제거하면 처분 대상의 폐기물이 남게 된다. 이 폐기물의 양을 줄이고 관리기간을 단축시키는 방안을 강구하는 것이 처분전에 수행하는 전처분(pre-disposal)의 주 목표이다. 처분후에는 건식처리된 과정과는 달리 장기적으로 관리하여야 하며, 물의 유입에 의한 침출 문제등 습식 환경도 고려하여야 한다. 따라서 궁극적으로 처분되어지는 폐기물에 대해서는 물의 영향을 파악하는 것이 필수적이다.(중략)

• Proceedings of the Korean Fiber Society Conference
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• 2002.04a
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• pp.215-218
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• 2002

Poly(vinyl alcohol)(PVA)는 1924년 W. O. Herrmann과 W. Haehnel이 Poly(vinyl esters)를 caustic soda 용액에서 비누화하여 합성한 뒤 많은 연구 및 사용되어지고 있는 고분자이다. 환경친화적이고, 인체에 무해하여 인공관절, 콘택트 렌즈 등에 이용이 되고 있다. 특히 구조가 선형적이고 zig-zag구조를 가지기 때문에 고강도, 고탄성을 갖는 섬유의 제조가 가능한 소재이다[1]. PVA섬유의 제조는 용매를 이용한 습식방사 및 겔방사로 섬유를 제조한다. (중략)

• Proceedings of the Korean Fiber Society Conference
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• 2007.11a
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• pp.207-208
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• 2007

• Proceedings of the Korean Fiber Society Conference
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• 2003.04a
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• pp.177-178
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• 2003

1934년 Formhals[1,2]에 의해 최초로 특허화된 전기방사(electrospinning)는 최근에 나노기술의 급격한 부각과 함께 과학분야에서 큰 관심의 대상이 되고 있다. 이러한 전기방사는 전형적인 섬유제조방법인 습식ㆍ건식ㆍ용융방사와는 달리 전기적인 힘(electric force)을 이용하여 머리카락 굵기의 100분의 1의 작은 크기의 직경을 갖는 섬유를 제조할 수 있는 방법이다[1,2]. 전기방사에 의해 제조된 웹은 단위 면적당 큰 표면적, 작은 기공, 높은 다공성을 가지고 있기 때문에 필터, 복합체의 강화제, 조직공학에서의 담체(scallold)뿐만 아니라 의료 분야 등에 응용될 수 있다[1,2]. (중략)

• Journal of Radiation Protection and Research
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• v.23 no.4
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• pp.251-257
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• 1998

A diffusion model of radioactive gaseous effluents is improved to apply for domestic nuclear power plants. Up to now, XOQDOQ computer code package developed by U. S NRC has been used for the assessment of radioactive plume dispersion by normal operation of domestic nuclear power plants. XOQDOQ adopts the straight-line Gaussian plume model which was basically derived for the plane terrain. However, since there are so many mountains in Korea, the several shortcomings of XOQDOQ are improved to consider the complex terrain effects. In this work, wind direction change is considered by modifying the wind rose frequency using meteorological data of the local weather stations. In addition, an effective height correction model, a plume reduction model due to plume penetration into mountain, and a wet deposition model are adopted for more realistic assessments. The proposed methodology is implemented in Yongkwang nuclear power plants, and can be used for other domestic nuclear power plants.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.14 no.4
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• pp.435-443
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• 2016

This paper describes the development of a dry operation process for PWR spent nuclear fuel, which is currently stored in the domestic NPP's storage pool, using a dual purpose metal cask. Domestic NNPs have had experience with wet type transportation of PWR spent nuclear fuel between neighboring NPPs since the early 1990s, but no experience with dry type operation. For this reason, we developed a specific operation process and also confirmed the safety of the major cask components and its spent nuclear fuel during the dual purpose metal cask operation process. We also describe the short term operation process that was established to be completed within 21 hours and propose the allowable working time for each step (15 hours for wet process, 3 hours for drain process and 3 hours for vacuum drying process).