• Title/Summary/Keyword: Longterm performance

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A Study on the Forecasting Model of the Required Cost for the Long-term Repair Plan in Apartment housings (공동주택의 장기수선계획 소요비용 예측모델 연구)

  • Lee, Kang-Hee;Yoo, Uoo-Sang;Chae, Chang-U
    • KIEAE Journal
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    • v.11 no.3
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    • pp.63-68
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    • 2011
  • Building deterioration would be proceeded by various causes such as physical, social, economic degradation. The deterioration would be inevitably prevented or delayed to get the decent function and performance in various building part and components. The maintenance and management are continued to provide the decent living condition for the household. The maintenance means mainly a repair, including the on-time and longterm plan. The longterm repair would be conducted by the systemic preparation in management activity and a required cost. Therefore, the annual due for the longterm repair plan is important to prepare the repair cost in a required time. In this paper, it aimed at analyzing the longterm repair cost and modelling to forecast the required cost in total area, number of household and time elapse in apartment housing. The estimation model of a repair cost is used with a power function which has a good statistics. Results of this study are shown that the sample has a longterm repair due in a $2,032won/m^2{\cdot}yr$ averagely which is higher than $912won/m^2{\cdot}yr$ in domestic. Second, the longterm repair due is proportionally correlated with the time elapse in both a total area and the number of household. Third, the estimation model for the longterm repair amount is suitable for the power function which is most in any other estimation models. Fourth, the ration of the longterm plan repair due a year to the cumulated longterm amount is about 26%.

Longterm Aging Characteristics of Distribution Polymer Housed Surge Arresters by Multistress Accelerated Aging (복합 가속열화를 통한 배전용 고분자 피뢰기의 장기 열화특성 예측)

  • Kim, Ju-Yong;Kwon, Tae-Ho;Park, Chul-Bae;Kim, Joon-Eel
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.20 no.8
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    • pp.691-696
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    • 2007
  • In this study accelerated aging test equipment was developed to simulate domestic weather condition for accelerated aging test of polymer housed distribution surge arresters. Polymer arresters were aged for 3,000 hours by this test equipment and chemical and electrical characteristics analysis of surge arresters were conducted after aging test. In addition, performance assessment of outdoor installed arresters for 3 years was conducted to compare aging effect between accelerated aging test and natural aging. Through this experiment it is verified that the capability of the proposed aging test for simulating natural aging and the housing material and disconnector of domestic polymer arresters can be deteriorated by the long time field operation.

Studie8 on Long-Term Performance Evaluation of Geotextiles -for Filter and Drainage- (필터 및 배수용 토목섬유의 장기적 성능 평가에 관한 연구)

  • 권우남
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.35 no.3
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    • pp.130-139
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    • 1993
  • In order to evaluate the long-term permeability performace of the geotextiles, for five different combination of geotextiles and soils the long-term column test method The results obtained are as follows; 1.The gradient range of the initial stage of the long-term permeability curves varied with respect to the soil types, while that of the final stage varied according to the interaction of the soil/geotextile system. 2.The time required for a given soil/geotextile system to reach a interactive stable stage was measured ahout 100 hours for the standard sand and 150 to 600 hours for the silty content soils, respectively. 3.There were no differences between the plain woven geotextile and the non-geotextile in the long-term permeability performance. 4.As the silt content increased, the long-term performance of the geotextiles decreased, and the limiting silt content was about 15%. 5.The thickness and area density of the geotextiles did not influence on the variation of the seepage quantities. 6.The ayerage slope and the transition time of the long-time flow curve were calculated. 7.In order to evaluate the mechanism of soil/geotextile system more perfectly, the gradient ratio test or the hydraulic conductivity test is required.

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Effects of Trust Determinants on Firm Performance in the Buyer-Supplier Relationships: Empirical Evidence from the Warehousing firms in Busan, South Korea (구매자와 공급자 관계에서 기업의 성과에 대한 신뢰 결정요인의 영향: 부산시 창고업을 대상으로)

  • Sung, Sinje;Kang, Sangmok
    • Journal of the Korean Geographical Society
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    • v.48 no.5
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    • pp.667-685
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    • 2013
  • This paper provides an empirical analysis of the effects of trust determinants on firm performance in the buyer-supplier relationships by considering warehousing firms in Busan, South Korea. We employed AVAS transformation regressions to address the limitations of linear regressions and found nonlinear relationships between firm performance and trust determinants. Specifically, "longterm and repeated interactions," "geographical proximity," and "cultures and norms of firms and formal institutions" had positive linear relationships with firm performance, and "information sharing and reciprocity" induced an increasing pattern in firm performance. Finally, "interdependence and asset specificity" and "uncertainty removal" led to a decreasing pattern in firm performance. These results suggest that the relationship between trust and firm performance is contingent on the trust determinants that are important source of trust in buyer-supplier relationships and the influence of trust determinants on firm performance varied according to their levels.

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Validation of the Korean Translated Dynamic Gait Index in Community-Dwelling Elderly (지역사회에 거주하는 노인을 대상으로 한 한글판 동적보행지수의 타당성)

  • Park, So-Yeon;Hwang, Su-Jin
    • Physical Therapy Korea
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    • v.17 no.1
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    • pp.43-52
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    • 2010
  • The Dynamic Gait Index (DGI) was developed and widely used as a clinical tool to assess balance performance during gait. The purpose of this study was to validate the Korean translated DGI using Rasch analysis. A total of 105 community-dwelling elderly was participated in this study (age range = 65~95 years; mean = 78.0 years). The translated DGI showed sound item psychometric properties, and the 8 items were arranged in order of difficulty for the total participants. The most difficult item was 'Steps' and the easiest item was 'Level surface'. Also, each of the original 4 rating scale categories satisfied the Linacre's essential criteria suggestions for optimal rating scale category effectiveness. Although, thirty eight person (36.2%) showed the maximal high score, but the most of them was no history of fall in the preceding year. For subjects who has falling history, all of the person's ability was arranged within the item's difficulty. The 8-item Korean translated DGI can be used to measure gain in elderly person with balance disorders without compromising important clinical measurement characteristics in Korea.

Environmental tobacco smoke and children's health

  • Hwang, Sang-Hyun;Hwang, Jong-Hee;Moon, Jin-Soo;Lee, Do-Hoon
    • Clinical and Experimental Pediatrics
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    • v.55 no.2
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    • pp.35-41
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    • 2012
  • Passive exposure to tobacco smoke significantly contributes to morbidity and mortality in children. Children, in particular, seem to be the most susceptible population to the harmful effects of environmental tobacco smoke (ETS). Paternal smoking inside the home leads to significant maternal and fetal exposure to ETS and may subsequently affect fetal health. ETS has been associated with adverse effects on pediatric health, including preterm birth, intrauterine growth retardation, perinatal mortality, respiratory illness, neurobehavioral problems, and decreased performance in school. A valid estimation of the risks associated with tobacco exposure depends on accurate measurement. Nicotine and its major metabolite, cotinine, are commonly used as smoking biomarkers, and their levels can be determined in various biological specimens such as blood, saliva, and urine. Recently, hair analysis was found to be a convenient, noninvasive technique for detecting the presence of nicotine exposure. Because nicotine/cotinine accumulates in hair during hair growth, it is a unique measure of longterm, cumulative exposure to tobacco smoke. Although smoking ban policies result in considerable reductions in ETS exposure, children are still exposed significantly to tobacco smoke not only in their homes but also in schools, restaurants, child-care settings, cars, buses, and other public places. Therefore, more effective strategies and public policies to protect preschool children from ETS should be consolidated.

Long-Term Performance of Safety Related Concrete Structures in Nuclear Power Plants (원전 콘크리트 구조물의 장기내구성능 평가)

  • Yoon, Eui-Sik;Paek, Yong-Lak;Lim, Jae-Ho;Chung, Yun-Suk;Choi, Kang-Ryong
    • Proceedings of the Korea Concrete Institute Conference
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    • 2006.11a
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    • pp.237-240
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    • 2006
  • Almost 30 years have been passed since the first nuclear power plant was operated in Korea. Many studies have been actively conducted from the early 1990's in order to develop the deterioration management system for concrete structures in NPPs(Nuclear Power Plants) accordingly. Base on these studies, a systematic deterioration management program has developed and operated since 1997. According to this program, systematic inspections to provide database and evaluation were periodically performed (every overhaul at intervals of $12{\sim}18$ month and every five years). Accumulated deterioration database was usefully utilized for the NPP PSR (Periodic Safety Review). In this paper, the long-term durability and integrity of Kori 1,2 NPP concrete structures which are the oldest ones in Korea were evaluated based on the precise inspection database and regulatory inspection results including compressive strength, depth of carbonation, amount of chlorination and spontaneous potential of reinforcing bar, etc. It was noted that Kori 1,2 NPP structures have not any serious durability problems.

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Effects of Dietary Supplementation of Conjugated Linoleic Acid (CLA) on Piglets' Growth and Reproductive Performance in Sows

  • Park, J.C.;Kim, Y.H.;Jung, H.J.;Moon, H.K.;Kwon, O.S.;Lee, B.D.
    • Asian-Australasian Journal of Animal Sciences
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    • v.18 no.2
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    • pp.249-254
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    • 2005
  • The objective of this study was to investigate effects of dietary level of CLA and the duration of feeding CLAcontaining diets on reproductive performance in sows and piglet growth rate. Tallow (3% in gestation diet and 5% in lactation diet, respectively) was incorporated as a fat source in control diet, and each 50% (dietary CLA level of 0.75% in gestation diet, and 1.50% in lactation diet, respectively) or 100% (dietary CLA level of 1.50% in gestation diet, and 2.50% in lactation diet, respectively) of tallow was replaced by a commercial CLA preparation containing 50% CLA isomers. Diets containing CLA were fed either from d 15 premating to weaning or d 74 post-mating to weaning. The level of dietary CLA and feeding duration did not affect litter size. High dietary level of CLA, however, decreased piglet weights at birth (p<0.01) and tended to decrease backfat thickness of sows at weaning. Longterm feeding of CLA-containing diets decreased piglet weights at weaning (p<0.05) and backfat thickness of sows at weaning (p<0.05). CLA supplemented in sow diet was transferred to fetus and piglets during pregnancy and nursing period, respectively. CLA contents of femoral muscle of piglets were 2.08 to 2.57 mg per g of fat at birth, and 2.36 to 4.47 mg at 10 days of age in CLA groups, while CLA was not detected in the control group. In conclusion, dietary supplementation of CLA tended to lower backfat thickness of sow and piglets' weight at birth or weaning, but did not affect total litter size. Dietary CLA was transferred efficiently during prenatal and postnatal periods of time through the placenta and milk, respectively.

Steel Design of Continuously Reinforced Concrete Pavement based on the Width of Transverse Crack (횡방향 균열 폭에 기초한 연속철근 콘크리트포장의 철근설계)

  • Kim, Kyeong-Jin;Kim, Dong-Ho
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.13 no.1 s.53
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    • pp.106-114
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    • 2009
  • The steel design based on the width of transverse crack which is the major factor to affect a long-term performance of continuously reinforced concrete pavement was developed. For this study, twenty-one cities of Texas were selected and the temperature data was collected at those locations during the past ten years. From the data, zero-stress temperatures were calculated by the PavePro program and the widths of transverse crack were analyzed by the CRCP program. The variables used to this numerical analysis were slab thickness, coefficient of thermal expansion of concrete, steel ratio, and design temperature. The total of 448 factorial runs were made and the regression analysis was performed using the results. Steel ratios from the regression equations were backcalculated and a steel design table was proposed.