• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2005년도 춘계학술대회 논문집
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• pp.239-245
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• 2005

Through the fatigue test of plastic gears using polyacetal polymer, this research aims at providing basic data for not only specifying operation conditions of plastic gears, but also designing dimensions of plastic gears with giving fatigue life and the estimated equation of fatigue life of plastic gears. That is, from the fatigue life curves, the estimated equation of fatigue life of plastic gears is taken out. For the estimated equation of fatigue life of plastic gears, this research provides two test methods; one is preserving non-limited temperature of tooth flank, the other is preserving limited temperature of tooth flank. As results, how the temperature of tooth flank affects the fatigue life is shown. In addition, based on the endurance limit, the essential factors of the unit load and K-factor are determined, which are needed in the design of gear by bending strength and surface durability.

• 가족자원경영과 정책
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• 제9권1호
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• pp.95-111
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• 2005

This study utilized representative data and categorized consumer groups by the style of purchase behavior, and examined the differences in consumers' evaluation for their consumption life and socio-demographic variables. The results of this study are summarized below First, the level of satisfaction for consumption life and evaluation of consumption level were in medium. The evaluation for society's consumption behavior was negative and did not agree that consumers' own behaviors are rational, but others' are conspicuous. The trend of consumers' conspicuous behavior and fashion-focused behavior were severe, but consumers' rationality was low. Second, males were more likely to be in rationality, but females were in both rationality and fashion-focused behaviors. Single consumers were more likely to follow fashion-based behavior, but married consumers prefer name-brand products and more likely to show conspicuous consumption. Low education was more related with convenience-focused behavior and rationality, but high education was more related with fashion-focused behavior and irrationality. Young consumers were more likely to show fashion-focused behavior, but old consumers follow convenience-focused behavior. Third, the level of satisfaction for consumption life was the highest in rational consumers, but low in consumers focused on name-brand products and on conspicuous consumption. The evaluation of consumption level was low in rational consumers and consumers focused on convenience, but high in consumers focused on name-brand products and on fashion. Rational consumers were more likely to evaluate society's consumption behavior negatively, and consumers focused on convenience were more likely to disagree for the discrepance in the evaluation of consumption behavior between consumers themselves and others.

• 한국콘텐츠학회논문지
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• 제12권7호
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• pp.453-462
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• 2012

본 연구는 삶의 질에 대해 평가할 수 있는 객관적인 평가지표를 마련하고, 지역별 인구구성에 따른 차별화된 삶의 질 정책 실현을 위한 기초자료를 마련하는데 목적이 있다. 삶의 질 평가지표를 개발하고, 연령별 삶의 질에 대한 가중치 차이가 있는지 분석하기위해, (1) 문헌 및 선행연구를 분석해 1차 평가지표를 선정한다. (2) 전문가 FGI를 실시하여 최종 평가지표를 도출한다. (3) 전문가를 대상으로 가중치 분석을 실시한다. 분석 결과, (1) 영역별 가중치는 가족안전, 경제안정, 주거문화, 보건복지, 교통환경 순서로 나타났다. 특히, 가족안전영역은 다른 분야보다 2배 이상 중요한 것으로 나타났다. (2) 연령별 가중치 분석결과, 연령이 높을수록 경제안정을 중요시하는 반면, 가족안전영역에 대하여는 연령이 많을수록 가중치가 떨어졌다. 소득수준이 높아지면서 1인당 주거면적과 도시공원면적, 전시공연의 중요성이 모든 연령에 걸쳐 주거 환경 문화에 관심이 높아지고 있음을 시사한다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 추계학술대회
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• pp.102-107
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• 2004

In general, major components of nuclear power plant have been evaluated based on 2-dimensional design codes conservatively. However, more exact assessment is necessary for continued operation beyond the design life. In this paper, 3-dimensional stress and fatigue analyses reflecting full geometry and monitored operating condition of reactor pressure vessel have been carried out. The analyses results showed that conservatism of current 2-dimensional evaluation based on design transient. Therefore, it is anticipated that the schemes developed from this research such as 3-dimensional finite element modeling, stress analysis and fatigue analysis related techniques can be utilized as fundamental tools for exact lifetime evaluation and license renewal of major nuclear components.

• 항공우주시스템공학회지
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• 제8권3호
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• pp.41-46
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• 2014

Fatigue evaluations for the rotor blades of commercial or military rotorcraft have been carried out using the safe life concept since 1950s. Particularly, in the case of a rotor blade made of a composite material, a highly reliable fatigue life could be predicted by evaluation the cumulative damage using combination of fatigue life curve and load spectrum. However, there is a limit in adequately evaluating the strength reducing phenomena caused by damages or defects generated during the manufacturing process or impact damage induced by operational usages, using only the safe life concept. In this study, the fatigue evaluation process based on the damage tolerance concept is described and illustrated by means of successful application to substantiate the retirement time of composite rotor blades.

• 한국해양공학회지
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• 제15권2호
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• pp.94-98
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• 2001

fatigue life and nondestructive evaluation were examined experimentally using surface crack specimen and compact tension specimen of 5083 aluminium alloy. Acoustic emission signals emanated during failure of aluminum alloys has been the subject of numerous investigations. Possible sources of AE during deformation have been suggested as the dislocations, fracture of brittle particles and debonding of these particles from the alloy matrix. Fatigue life and penetration behavior of long surface crack can be evaluated quantitatively using K values proposed by authors. The influence of stress ratio on the frequency characteristics of AE signals were investigated.

• 대한기계학회논문집A
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• 제28권6호
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• pp.663-669
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• 2004

A nuclear power plant is composed of a number of primary components. Maintaining the integrity of these components is one of the most critical issues in nuclear industry. In order to maintain the integrity of these primary components, a complicated procedure is required including regular in-service inspection, failure assessment, fracture mechanics analysis, etc. Also, experts in different fields have to co-operate to resolve the integrity issues on the basis of inspection results. This integrity evaluation process usually takes long, and thus, is detrimental for the plant productivity. Therefore, an effective safety evaluation system is essential to manage the integrity issues on a nuclear power plant. In this paper, a web-based fatigue life evaluation system for primary components in nuclear power plant is proposed. This system provides engineering knowledge-based information and concurrent and collaborative working environment through internet, and thus, is expected to raise the efficiency of integrity evaluation procedures on primary components of a nuclear power plant.

• 한국건축시공학회지
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• 제8권1호
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• pp.97-102
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• 2008

The report of the Korean Board of Audit and Inspection(BAI) on May 2007 indicates the problems of Life Cycle Cost (LCC) analysis and evaluation in the Design-Build(Turn-Key) and alternative bidding system. The point which the report indicates is that the cost estimation system for LCC analysis has nothing in common each other and there's no consistency among the repair cycle and ratio per facilities parts. For solving these problems, BAI demands the establishment of the guidelines for LCC analysis and evaluation from the competent authority Korean Ministry of Construction And Transportation(MOCT). The objective of this study is to develop the improvement directions for LCC analysis and evaluation which are suitable to the public construction projects especially for the Design-Build and alternative bidding system in Korea. For this study, the LCC related raws and regulations, LCC analysis guidelines of public cooperations, actual condition of LCC analysis and evaluation which include, the elements of LCC, the estimation rules of the initial cost and the maintenance cost, the analysis standards of time value of money, etc. are investigated to provide the improvement directions for LCC analysis and evaluation.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 춘계학술대회
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• pp.279-284
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• 2003

A nuclear power plant is composed of a number of primary components. Maintaining the integrity of these components is one of the most critical issues in nuclear industry. In order to maintain the integrity of these primary components, a complicated procedure is required including regular in-service inspection, failure assessment, fracture mechanics analysis, etc. Also, experts in different fields have to co-operate to resolve the integrity issues on the basis of inspection results. This integrity evaluation process usually takes long, and thus, is detrimental for the plant productivity. Therefore, an effective safety evaluation system is essential to manage the integrity issues on a nuclear power plant. In this paper, a web-based fatigue life evaluation system for primary components in nuclear power plant is proposed. This system provides engineering knowledge-based information and concurrent and collaborative working environment through internet, and thus, is expected to raise the efficiency of integrity evaluation procedures on primary components of a nuclear power plant.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2006년도 춘계학술대회논문집
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• pp.734-737
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• 2006

For the comfortable housing life, an urban environment should give comfort and pleasantness to people living in house and in city. There are lots of environmental conditions in city affecting house and life and most of all the noise pollution have been become factor that makes people's life hard without need to say. Recently researches have been performed to create comfortable urban environment and a study on the evaluation of urban environmental sounds is now undergoing. This study aimed to analyse the subjective characteristics through the subjective evaluation to the sounds measured with physical parameters and eventually to find out evaluation method for urban environmental sounds. Vocabularies applied to previous studies were used for the subjective evaluation and sound sources recorded in specific places were presented with picture at the same time.