• 제목/요약/키워드: Aging Resistance

검색결과 426건 처리시간 0.027초

가교시간에 따른 고분자 재료의 트래킹성과 자외선 열화특성 (Tracking Resistance and UV Degradation Property of Polymeric Insulating Materials by Cross-Link Time)

  • 천종욱;이운용;조한구
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2002년도 하계학술대회 논문집
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    • pp.447-450
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    • 2002
  • Recently polymeric insulators and arresters are being used for outdoor high voltage applications. Polymeric insulators for transmission line have significant advantages over porcelain and glass insulators, especially for ultra-high voltage(UHV) transmission lines. Their advantages are light weight, vandalism resistance and hydrophobicity. Polymeric insulator kind are a relatively new technology, but their expected life is still unknown. In this paper, the material property for polymeric insulating material such as silicone rubber and EPBM is investigated by cross-link time and the relation between tracking resistance and W resistance is analyzed by IEC 60587 and W aging experiment.

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금구류 히트사이클 시험용 자동 저항측정 시스템 개발 (Development of Automatic Resistance Measuring System for Aluminum Connector)

  • 박성균;손화영;류재남;김경환;박병락;박충열;김언석
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1997년도 추계학술대회 논문집 학회본부
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    • pp.161-163
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    • 1997
  • Heatcycle testing for aluminum connector is very important. But because of connecting or disconnecting the test circuit, measuring resistance is difficult. Also the previous measuring resistance instrument is analog type. So measuring method is difficult. And four measuring points for one test circuit cause difficulty in automation. In this paper we developed the automatic system for measuring resistance. Automation will allow more information to be gathered, which will lead to the connector aging process being better understood and controlled.

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에폭시/층상실리케이트 나노콤포지트의 주파수 가속열화에 따른 부분방전 저항성 (Partial Discharge Resistance According to Frequency Acceleration Deterioration of Epoxy/Layered Silicate Nanocomposites)

  • 박재준
    • 전기학회논문지
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    • 제62권12호
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    • pp.1694-1699
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    • 2013
  • Frequency accelerated partial discharge resistance (PDR) aging of epoxy/layered silicate nanocomposite with 1.5wt % additions of layered silicate was investigated in comparison with that of epoxy without layered silicate in terms of PD(partial discharge) erosion depth. It was found that the change in the erosion depth is far smaller in specimens with layered silicate than those without layered silicate nano particles. Frequency acceleration can be done from 60Hz to 1000Hz. But the depth of erosion is less proportional to frequency. Acceleration factor is almost 2 times between 500Hz and 1000Hz, but it is much less than about 8.3 times between 60Hz and 500Hz. This superior PD resistance is caused by the presence of nanofillers, anano-effect due to closely packed nanofillers, and strong chemical bonds at layered silicate nanofillers /resin interfaces.

Hydroxy Silicone Oil이 실리콘 고무의 절연특성에 미치는 영향(1) (Effects of Hydroxy Silicone Oil on Insulation Properties of Silicone Rubber(1))

  • 강동필;박효열;안명상;이웅재;이후범;오세호
    • 한국전기전자재료학회논문지
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    • 제16권11호
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    • pp.1001-1007
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    • 2003
  • The silicone fluids have been generally used as processing agent in silicone rubber(SIR) compounding. The addition of hydroxy silicone (HS) fluids to SIR for insulator housing material is required to meet the good electrical performance and the good processability. In this study, SIR with HS fluids was evaluated to investigate how the kinds of them affect insulation properties. The contact angle of the virgin sample of 40-HS SIR was low and its recovery rate was also slow. The recovery rate of 50-HS SIR was the highest being decreased with the viscosity increase of HS fluids. The tracking resistances and the corona aging resistance of 70-HS SIR and 1,040-HS SIR were excellent Tracking resistance depended largely on heat resistance of silicone fluids. But arc resistance didn't depend merely on the kind of silicone fluids.

The Impact of Organokines on Insulin Resistance, Inflammation, and Atherosclerosis

  • Choi, Kyung Mook
    • Endocrinology and Metabolism
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    • 제31권1호
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    • pp.1-6
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    • 2016
  • Immoderate energy intake, a sedentary lifestyle, and aging have contributed to the increased prevalence of obesity, sarcopenia, metabolic syndrome, type 2 diabetes, and cardiovascular disease. There is an urgent need for the development of novel pharmacological interventions that can target excessive fat accumulation and decreased muscle mass and/or strength. Adipokines, bioactive molecules derived from adipose tissue, are involved in the regulation of appetite and satiety, inflammation, energy expenditure, insulin resistance and secretion, glucose and lipid metabolism, and atherosclerosis. Recently, there is emerging evidence that skeletal muscle and the liver also function as endocrine organs that secrete myokines and hepatokines, respectively. Novel discoveries and research into these organokines (adipokines, myokines, and hepatokines) may lead to the development of promising biomarkers and therapeutics for cardiometabolic disease. In this review, I summarize recent data on these organokines and focus on the role of adipokines, myokines, and hepatokines in the regulation of insulin resistance, inflammation, and atherosclerosis.

화재피해를 입은 철근콘크리트 단주시험체의 보수재료 적용 후 내화성능 평가 (Fire Resistant Performance after Application of Repaired Materials for Fire-Damaged Reinforced Concrete Column)

  • 심상락;류동우
    • 대한건축학회논문집:구조계
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    • 제36권5호
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    • pp.147-154
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    • 2020
  • Currently, there are no specific repair methods for RC structures damaged by fire, and repair methods are applied when durability deteriorates due to aging. In addition, a number of recent studies have been reported that have conducted fire resistance assessment of the repair materials themselves, assuming exposure to high-temperature environments such as fires. However, researches that evaluate the fire resistance performance of the repair materials by applying existing repair materials to the actual fire damaged reinforced concrete structures are very rare. Therefore, in this study, a number of existing repair materials were applied to fire-damaged concrete column to compare and evaluate the fire resistance performance with the original cover concrete.

Sequestration of Organic Pollutants in the Environments: Implications on Bioavailability and Bioremediation

  • Nam, Kyoungphile
    • 한국지하수토양환경학회:학술대회논문집
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    • 한국지하수토양환경학회 2000년도 추계학술대회
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    • pp.107-118
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    • 2000
  • For the last several decades, the fate of organic pollutants has been extensively studied in natural environments with emphasis on sorption and desorption phenomena. Although the mechanisms involved are not clear yet there is a consensus about the existence of hysteresis in the sorption and desorption of organic pollutants. Furthermore, it is found that hysteresis is the outcome of slow nonequilibrium sorption of organic pollutants, which results in the formation of desorption-resistant fractions of the pollutants. Desorption-resistant fractions may increase as a function of the residence time of the pollutants in the environments. Field monitoring data show a slow but continuous decline of chemicals applied to soil, followed by little or no subsequent disappearance. One plausible explanation for such resistance to biodegradation, desorption, or extraction can be attributed the gradual movement of organic pollutants to less accessible remote sites inside the matrix with time. This phenomenon has been termed sequestration or aging. The fact that some pollutants are sequestered in soil with time may have a great impact on bioremediation and risk assessment, Some portion of the resistant pollutants may still be present in the environments after bioremediation. It requires vigorous means to completely remove the aged portion that may not be further bioavailable. However, precaution should be taken since aging is not always evident. Aging seems to be soil and chemical specific.

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Effect of thermal aging on the mechanical, intergranular corrosion and corrosion fatigue properties of Z3CN20.09M cast duplex stainless steel

  • Ti, Wenxin;Wu, Huanchun;Xue, Fei;Zhang, Guodong;Peng, Qunjia;Fang, Kewei;Wang, Xitao
    • Nuclear Engineering and Technology
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    • 제53권8호
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    • pp.2591-2599
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    • 2021
  • The effect of thermal aging at 475 ℃ and 750 ℃ of Z3CN20.09M cast duplex stainless steel (CDSS) on microstructure, mechanical and intergranular corrosion properties were investigated by transmission electron microscope (TEM), nano indenter, scanning electron microscope (SEM) and corrosion fatigue test system. The result indicated that the spinodal decomposition and G precipitated were occurred after aged at 475 ℃, as well as sigma precipitated at 750 ℃. The microstructure degeneration of ferrite was saturated after aged for 2000h and 200 h at 475 ℃ and 750 ℃ respectively. The mechanical properties, intergranular corrosion resistance and corrosion fatigue lives were continuing deteriorated with increasing the aging time at both temperatures. The difference of the degeneration mechanisms of Z3CN20.09M CDSS aged at 475 ℃ and 750 ℃ was analyzed.

Ceramic PTC thermistor의 금속접촉저항과 입계전위장벽 (Analysis on Metal Contact Resistance and Grain Boundary Barrier Height of Ceramic PTC Thermistor)

  • 전용우;임병재;홍상진;소대화
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2006년도 추계학술대회 논문집 Vol.19
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    • pp.235-236
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    • 2006
  • The contact resistance and grain boundary potential barrier of ceramic $BaTiO_3$ PTCR were investigated. The electroless plated Ni, evaporated Al, and Ag paste were chosen as electrode materials of PTCR device for comparison analysis before and after heat treatment. The contact resistance of electrode were measured by electrometer (dc), digital multimeter (dc), and LCR meter (ac). In the case of Al electroded samples, the heat treatment and protective oxide layer had high resistance and effect on the stability of PTCR effect against contact resistance degradation, but the Ag-paste had comparably high contact resistance before heat treatment and decreased after heat treatment with safe. On the other hand, the samples with electroless plated Ni electrode had good properties of contact resistance against aging.

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Factors Influencing Post-Adoption Resistance to Self-Order Kiosks at Fast-Food Restaurants: A Focus on the New-Silver Generation

  • Hwaran Lee;Eunkyung Kang;Kyung Young Lee;Minwoo Lee;Sung-Byung Yang
    • Journal of Smart Tourism
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    • 제3권2호
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    • pp.23-36
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    • 2023
  • Due to the phenomenon of aging, a new consumer segment known as the "new-silver generation" is emerging. Unlike the previous silver generation, this generation possesses significant economic power and consuming willingness, attracting attention from consumer goods companies. However, both the new-silver generation and the elderly face challenges in adopting contactless or self-service technologies such as self-order kiosks, resulting in negative reactions. Therefore, this study aims to investigate the attitude and response of the newsilver generation towards kiosks, as well as the factors influencing their resistance to such technology. By applying theoretical perspectives from the innovation resistance model, technostress theory, and the value-based model, this study identifies influencing factors for innovation resistance among the new-silver generation when using contactless technologies implemented in fast-food restaurants. The findings indicate that a lower awareness of new technologies and services corresponds to decreased adoption resistance, while a higher perceived value leads to more positive behaviors and attitudes among the new-silver generation utilizing kiosks at fast-food restaurants.