• 펄프종이기술
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• 제46권5호
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• pp.35-42
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• 2014

Many historical archives have been deteriorated by aging with time. Various kinds of defects such as worm-hole, yellowing, brittleness are observed and their severity was dependent on raw material type, storage condition, and so on. For a long-term use and storage, a proper preservation treatment is required. Many studies on preservation and conservation have been carried out on hanji which was made from mulberry fiber, but there are few concerns on foreign paper. Therefore, aging and chemical strengthening treatment was done on paper made of bamboo and wood fibers depending on aging condition, the type and pickup weight of chemicals and treatment method. When methyl cellulose was treated with impregnation or brushing, the aged paper was strengthened effectively. The strengthening effect by chemicals was dependent on the aged condition of the paper.

• 펄프종이기술
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• 제42권4호
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• pp.15-24
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• 2010

Many efforts to understand the deterioration processes of the beeswax-treated volume of "The Annals of Joseon Dynasty" have been made. However, most previous studies have focused on individual sample sheet of the beeswax-treated paper but not book volume format. In this study, humid cycling accelerated aging for duplicated beeswax-treated book volume and Hanji book volume were carried out to examine differences in the deterioration of different parts of each volume as well as between the two book volumes during the aging. As results, it is found that the deterioration rate for the beeswax-treated volume is higher than that for the Hanji book volume. Different parts in each volume show different magnitude of deterioration. In particular, outer sides in both beeswax-treated and Hanji book volumes, which are directly exposed to the air, are deteriorated more seriously than inner sides. It is also observed that inner sides are considerably deteriorated during the aging, implying that inner deterioration may have different mechanisms from outer deterioration.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 하계학술대회 논문집
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• pp.601-604
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• 2001

22.9 kV CV power cable is very important factor of underground distribution power line. Cyclic aging for 14days is performed to remove a large amount of the volatiles found in freshly manufactured cable. In this paper, we examined AC breakdown characteristics of CV power cable before and after cyclic aging for 14days. As the result, even if there were some exceptions, the AC breakdown voltage before aging was lower than that after aging, but most of the results were that the AC breakdown voltage after aging was lower than that before aging.

• Corrosion Science and Technology
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• 제5권3호
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• pp.99-105
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• 2006

This paper is to investigate feasibility on quantitative aging state of epoxy coating on concrete wall in containment structure under operation of nuclear power plants. For evaluating the physical characteristics of the epoxy coating, adhesion strengths of two kinds of degraded epoxy coating systems on both steel surfaces and concrete surfaces were measured via accelerated aging. Comparatively impedance data taken by ultrasonic test were also taken to relate with adhesion data. After aging, in case of concrete, from half of specimens, aging of epoxy coating was developed. As for steel, on $4^{th}$ inspection day, adhesion force was failed. To improve reliability on quality degradation of epoxy, relationship between adhesion and impedance was analyzed. By tracing to co-respond to these data, it was possible to Fig. out physical state of as-built epoxy coating. The possibility to develop new methodology of time - dependent aging state on epoxy coating was found and discussed.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 하계학술대회 논문집
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• pp.596-598
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• 2000

This paper presents a new accelerating aging test facility for distribution lightning arresters. Aging parameters of lightning arrester are moisture ingress, electrical stress and surge absorption and so on. In this system, we applied 13.2kV to 6 samples and controled temperature and humidity of chamber and measured leakage currents of the all samples. Also we developed accelerating aging cycle which consists of -35$^{\circ}C$∼90$^{\circ}C$ temperature and 40%∼90% humidity. Through the aging test we found out the leakage current of aged sample increases rapidly according to the temperature rising. Hereafter we can determine the replacement guide of leakage current for field operating arresters and condition assessment of aged samples through this aging test.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 C
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• pp.2274-2276
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• 2005

Cyclic aging for 14days is performed to remove the large amount of the volatiles found in freshly manufactured cable. In this paper, we examined lightning impulse characteristics of power cable before and after cyclic aging for 14days. As the result, the breakdown voltage after aging was lower than that before aging, but the breakdown voltage after aging was higher than that before aging in TR CNCV-W $60mm^2$ power cable.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 하계학술대회 논문집
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• pp.119-122
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• 2000

Recently polymer insulators are being used for outdoor high voltage applications. Polymer insulators for transmission line have significant advantages over porcelain and glass insulators, especially for ultra-high voltage transmission lines. Their advantages are light weight, vandalism resistance and hydrophobicity. Polymer insulators are a relatively new technology, but their expected life is still unknown. Therefore these estimating technique are very important. Their life time is related to weathering and operating condition. Multi-aging test is requested because aging factor is occurred by multi-aging than unique aging. The aging test about polymer insulators have mainly carried out by IEC 61109. This paper presents multi-stress chamber experiments and tracking wheel test to examine the tracking and erosion performance of polymer insulator for transmission. Multi-stress testing is able to demonstrate deficiencies of polymer insulator materials and designs, including the nature of interfaces in insulation design. We have investigated IEC 61109 Annex C (5000h aging test) and CEA tracking wheel test as test methods of artificial accelerated aging. The aging degree of polymer insulator is estimated by leakage current, measurement of hydrophobicity degree, damage conditions of insulator surface, withstand voltage test etc.

• Nuclear Engineering and Technology
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• 제36권5호
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• pp.475-484
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• 2004

Extending the lifetime of a nuclear power plant [(hereafter referred to simply as NPP)] is one of the most important concerns in the global nuclear industry. Cables are one of the long-life items that have not been considered for replacement during the design life of a NPP. To extend the cable life beyond the design life, it is first necessary to prove that the design life is too conservative compared with actual aging. Condition monitoring is useful means of evaluating the aging condition of cable. In order to simulate natural aging in a nuclear power plant. a study on accelerated aging must first be conducted. In this paper, evaluations of mechanical aging degradation for a neoprene cable jacket were performed after accelerated aging under tcontinuous and intermittent heating conditions. Contrary to general expectations, intermittent heating to the neoprene cable jacket showed low aging degradation, 50% break-elongation, and 60% indenter modulus, compared with continuous heating. With a plant maintenance period of 1 month after every 12 or 18 months operation, we can easily deduce that the life time of the cable jacket of neoprene can be extended much longer than extimated through the general EQ test. which adopts continuous accelerated aging for determining cable life. Therefore, a systematic approach that considers the actual environment conditions of the nuclear power plant is required for determining cable life.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 추계학술대회 논문집
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• pp.255-257
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• 2001

In this paper, the silicon rubber insulator for transmission line was experimented for 1,000 hours aging test in salt-fog condition. To evaluate and examine the aging properties of silicon rubber insulator for test, the leakage current of surface was measured. Also hydrophobicity and scanning electron microscopy were compared with initial and aged sample respectively Above results, we can confirm that the surface properties of silicon rubber insulator easily aged by salt-fog condition.

• 에너지공학
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• 제21권1호
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• pp.1-17
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• 2012

원자력 인력 고령화는 원전 수출에 따른 새로운 인력 수요 증가에 못지 않는 중요한 인력 문제를 야기할 수 있다. 고령화된 숙련 전문인력의 대거 퇴직에 따른 고급 인력난과 원자력 기술능력 약화는 한국 원자력의 경쟁력을 크게 약화시킬 수 있다. 본 연구는 한국 원자력 관련 기관 및 업체들에 대해 2001년과 2010년 국내원자력 기관의 인력 현황에 대한 통계조사에 근거하여 약 10년의 기간 동안 원자력 인력 변동 추이 등의 인력 현황 통계자료를 활용했다. 이를 토대로 조사대상 기관별로 그리고 통합적으로 원자력 인력의 고령화 수준을 검토한다. 그리고 원자력 인력 고령화 문제에 대비하기 위한 인력 충원의 방향과 한국 원자력 인력 수급의 문제점을 해소해 나가기 위한 대응방안을 제시할 것이다.