• East Asian Economic Review
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• 제25권4호
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• pp.361-401
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• 2021

This paper sets up a two agent small open economy with monopolistically competitive firms and catching up with the Joneses to investigate the labor and capital Laffer curve, taking into account aging population along the line of Auray et al. (2016), Galí and Monacelli (2005), and Trabandt and Uhlig (2011). The paper finds that the higher the market power of firms is, the larger the consumption inequality between asset holders and non-asset holders is in the economy with aging population. It also finds that there is room for government to increase the tax revenue by raising tax rates under the economy with higher markup, as households will work more hours to compensate for their loss of labor income to tax hikes. The expected maximum tax revenue is likely to shrink with progressive taxations, since non-asset holders with additional dividend income work less and consume more. The paper finds that the fiscal multiplier decreases with the degree of progressive redistribution.

• 한국안전학회지
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• 제17권4호
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• pp.71-79
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• 2002

It was attempted to evaluate the degree of degradation of thermally aged 2.25-1Mo steek by ultrasonic monlinear parameter(UNP) measurement and X-ray diffraction analysis of extracted carbide. Artificial aging was performed to simulate the microstructural degradation in 2.25Cr-1Mo steel arising from long time exposure at $540{\circ}C$. Microstructural analysis (number of carbides per unit area) and measurements of mechanical properties(Vickers hardness, DBTT) and degradation evaluation parameters(UNP and intensity ration of X-ray diffraction peak of electrolytically extracted carbide) were performed. Both of UNP and intensity ratio of X-ray diffraction peak for M6C carbide to that of M23C6 carbide(IR) increased abruptly in the initial 1000 hour of aging and then changed little. UNP and IR were proposed as potential parameters to evaluate the degree of aging degradation of 2.25Cr-1Mo steel.

• 전기학회논문지
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• 제59권4호
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• pp.693-699
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• 2010

General transformer's life is known as paper insulation' life. If a transformer is degraded by these aging factors, it is known that electrical, mechanical and chemical characteristics for transformer's oil-paper are changed. When the kraft paper is aged, the cellulose polymer chains break down into shorter lengths. It causes decrease in both tensile strength and degree of polymerization of paper insulation. The paper breakdown is accompanied by an increase in the content of furanic compounds within the dielectric liquid. In this paper it is aimed at analysis on correlation between aging characteristics for insulating diagnosis of thermally aged paper. For investigating the accelerated aging process of oil-paper samples accelerating aging cell was manufactured for estimating variation of paper insulation during 500 hours at $140^{\circ}C$ temperature. To derive the results, it was performed analysis such as tensile strength(TS), depolymerization(DP), dielectric strength(DS), relative permittivity, water content(WC) and furan compound(FC) for aged paper. Also for analyzing correlation between insulating degradation characteristics, we used linear regression method. As as results of linear regression analysis, there was a close correlation between TS and DP. WC, FC. But dielectric strength was a weak correlation with aging time.

• 한국전기전자재료학회논문지
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• 제11권11호
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• pp.1035-1042
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• 1998

After the 1990's, a computer-aided partial discharge(PD) measurement system was referred in part of aging diagnosis using digital signal processing as the new technology has been studied. The PD patterns and relevant information for pattern recognition are discussed in PD research area, because discharge quantity(q), the number of discharge pulse(n) and the applied boltage phase($\varphi$) was combined with the system information of the aging state. This paper investigates the discharge phase and quantity, as well as the number of discharge(n) with regard to discharge signals generated in power cable. therefore, according to characteristic analysis on the distribution of $\varphi$, q and n, it is able to apply in the aging analysis of power cable which visual observation is impossible and distribution change of discharge signals offers much information for risk degree on aging progress of insulation materials.

• KIEAE Journal
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• 제7권1호
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• pp.81-93
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• 2007

Due to increasing awareness about the risk which will be caused by fast aging of population, the importance of aging friendly environment including housing has been paid much attention both individually and socially. In this regard, recently, in Korea, diverse elderly living facilities have increased in its number. Because of little experience, however, there have not been enough holistic understanding about aging friendly housing. Accordingly, most previous literature which introduced elderly housing to Korean society have translated differently, thereby caused more confusion. To facilitate communication about aging friendly housing, clear and consistent definition of its type and comprehensive range needs to be delineated. The purpose of this study is to classify various elderly housing alternatives in architecturally understandable way. This study was proceeded by content analysis of existing literature on elderly housing environment. A comprehensive review on the concept and existing classification of elderly housing was done prior to main analysis of translated Korean words. After classifying the Korean words of definition, systematic classification which focused on two important criteria of determining physical characteristics, such as space sharing degree and intentional plannedness was delineated and suggested. This research shows the first step toward the theoretical foundation for elderly housing classification.

• 전기학회논문지
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• 제61권8호
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• pp.1148-1152
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• 2012

The vegetable-based insulating oils are substitutes for mineral oils in oil-filled transformer. The important properties of vegetable insulating oil is their higher flash/fire point and biodegradability than conventional mineral oils. The large oil-filled transformer eliminate the risk of explosion and fire should the transformer fail and oil ignite owing to high flash/fire point of vegetable insulating oil. In addition, higher biodegradability of vegetable insulating oils can let the oil spill damage reduced. In this experiment, the real oil-filled transformers using mineral oil and vegetable oil have accelerated aging. After working on the 100% accelerated aging experiment were conducted comparing the transformer. The hottest-spot temperature using thermal coefficients were calculated to determin the degree of accelerated aging. As a result, apply mineral oil transformer in accordance with the accelerated aging life come to an end. In contrast, vegetable insulating oils showed the opposite characteristics. Vegetable insulating oil compared to the mineral oil are found to be an long life. As a result, the vegetable oil has a long-term stability.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 Techno-Fair 및 합동춘계학술대회 논문집 전기물성,응용부문
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• pp.183-184
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• 2008

The aim of this study is to find out the effects of thermal aging condition on dielectric strength and degree of crtstallinity of XLPE insulation. Thermal properties of XLPE insulation were investigated by DSC(differential scanning calorimetry) and dielectric strength were analyzed using AC BDV tester. Aging of XLPE samples were conducted through different four conditions. The degree of crtstallinity and AC BDV were changed by thermal history. From these results, it can be suggested that DSC and AC BDV test are suitable for diagnostic method of extra high voltage XLPE cable.

• 한국전기전자재료학회논문지
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• 제12권1호
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• pp.11-17
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• 1999

Aging characteristics of the crosslinked polyethylene have been measured after applying electrical, thermal and combined stresses. ICP and FT-IR measurements confirmed diffusion of low molecular weight components such as antioxidant and presence of carbonyl group. Carbonyl group of aged crosslinked polyethylene under combined stress was detected by FT-IR. As deterioration of the crosslinked polyethylene progresses, crystallinity degree and density decrease. Also, dielectric properties have been measured by tan $\delta$ and $\varepsilon$$_{r}$ measurements. The three-parameter Weibull distribution was found to be the best suited among other probabilistic distribution representing the dielectric breakdown strength of aged crosslinked polyethylene. The scale parameter and location parameter decreases as the applied stress increases. The shape parameter increases as the stress increases.s.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 추계학술대회 논문집 전기물성,응용부문
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• pp.179-182
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• 2002

XLPE compound have used for insulation of 22.9(kV) power cable. But tree retardant power cable has developed and is going to br used commonly. TR XLPE compound retard production and growth of water tree. In this paper, tensile strength, elongation at break, degree of crosslinking, lightning impulse test, AC breakdown test, cyclic aging for 14days and accelerated water treeing test of TR XLPE insulated power cable were examined according to the KEPCO buying spec. & AEIC CS 5-94 standards. before and after As the result, tensile strength, elongation at break and degree of crosslinking test results of TR XLPE insulation were higher than requirement values. After accelerated water treeing test for 120 days, 240 days and 360 days, AC breakdown voltages were not decreased for accelerated water treeing aging duration

• 한국산학기술학회논문지
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• 제19권6호
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• pp.440-446
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• 2018

본 논문은 고령인력이 조직 혁신에 미치는 효과와 연령 다양성이 이러한 관계를 어떻게 조절하는지를 중심으로 살펴본다. 지식경영 기반 관점에 근거하여, 본 연구는 기업 특유적 지식과 조직 내외부 사회적 연결망 측면에서 고령인력이 일정 정도 조직 혁신에 기여할 수 있을 것으로 보았다. 반면, 고령인력 비중이 지속적으로 늘어나게 되면 새로운 지식 창출관점에서 한계를 가질 수 있으므로 조직 혁신에 미치는 긍정적 효과보다는 부정적 효과가 보다 강하게 나타날 것으로 예상하였다. 이에 더하여, 고령인력과 조직 혁신 간 비선형적 관계를 조절하는 요인으로 연령 다양성의 효과에 대해 살펴보았는데, 본 연구는 새로운 지식의 창출이라는 측면에서 연령 다양성이 고령인력과 조직 혁신 간 비선형 관계를 조절할 것으로 예측하였다. 실증 분석을 실시한 결과, 예측한대로 고령인력과 조직 혁신은 역 U자 관계를 가지고 있었으며, 연령 다양성은 이러한 역 U자 관계를 조절하는 역할을 하는 것으로 나타났다. 이러한 이론적 논의와 실증 결과는 고령인력이 조직 혁신에 미치는 다양한 효과들을 보다 다각적으로 검증하고 이러한 관계에 영향을 줄 수 있는 보다 다양한 요인들에 대한 탐색이 이루어져야 함을 보여준다.