• International Journal of Reliability and Applications
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• 제2권1호
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• pp.1-26
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• 2001

The purpose of this paper is to introduce a proportional reversed hazard rate model, in contrast to the celebrated proportional hazard model, and study some of its structural properties. Some criteria of ageing are presented and the inheritance of the ageing notions (of the base line distribution) by the proposed model are studied. Two important data sets are analyzed: one uncensored and the other having some censored observations. In both cases, the confidence bands for the failure rate and survival function are investigated. In one case the failure rate is bathtub shaped and in the other it is upside bath tub shaped and thus the failure rates are non-monotonic even though the baseline failure rate is monotonic. In addition, the estimates of the turning points of the failure rates are provided.

• Nuclear Engineering and Technology
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• 제50권8호
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• pp.1314-1323
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• 2018

For nuclear power plants (NPPs) to have long lifetimes, ageing is a major issue. Currently, ageing management for NPP systems is based on correlations built from generic experimental data. However, each system has its own characteristics, operational history, and environment. To account for this, it is possible to resort to prognostics that predicts the future state and time to failure (TTF) of the target system by updating the generic correlation with specific information of the target system. In this paper, we present an application of particle filtering for the prediction of degradation in steam generator tubes. With a case study, we also show how the prediction results vary depending on the uncertainty of the measurement data.

• 한국동물학회지
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• 제20권3호
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• pp.129-134
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• 1977

CdR aminohydrolase의 활성을 老化와의 관련하에서 보기 위해서 초라피(Drosophila melanogaster)의 이효소의 활성을 발생단계별로 측정하여 다음의 결과를 얻었다. 1. 초파리에서 CdR이 분해되는 과정은 쥐나 생쥐와 마찬가지로 $CdR \\to UdR \\to U$임을 알수 있었다. 2. CdR-aminohydrolase외 활성은 유충과 번데기에서 검출이 불가능하였고 성체에서만 검출되었다. 3. 성체의 효소활성은 젊은 개체에 비해서 늙은 개체에서 증가를 보였다. 4. 실험의 결과는 CdR-aminohydrolase의 활성이 초파리의 老化또는 발생단계와 관련성이 있음을 시사하였다.

• 한국의류학회지
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• 제38권4호
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• pp.540-556
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• 2014

This research investigated the effective conditions to dye cotton with commercial indigo leaf powder. We tested dyeing conditions of: pH of dyebath (6.5, 9-12), heating ($20^{\circ}C$, $50^{\circ}C$, $70^{\circ}C$, $90^{\circ}C$), ageing (0, 0.5, 1, 4, 24 hours), reduction time (0, 30, 60 min), and dyeing temperature ($2^{\circ}C$, $10^{\circ}C$, $20^{\circ}C$, $50^{\circ}C$, $70^{\circ}C$, $80^{\circ}C$), dyeing was conducted for 20 minutes. The highest K/S value was obtained when cotton was dyed using pH 11 dyebath, heated at $50^{\circ}C$ for 30 minutes, aged for 24 hours at room temperature ($20^{\circ}C$), reduction carried out for 30 minutes, and dyed at $50^{\circ}C$. It is proposed that the K/S value is primarily influenced by the dyebath pH and dyeing temperature, followed by the presence or absence of ageing time and reduction time. The color of cotton with high K/S values was B type by Munsell hue value, which was similar to the color obtained in previous studies by freshly made indigo leaf powder and indigo leaf juice. The results indicate that the dyeing conditions established in this research are suitable to maximize the dyeability of commercial indigo leaf powder and that the indigo leaf powder can be used as a substitute for fresh indigo leaf juice.

• 지역사회간호학회지
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• 제9권1호
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• pp.64-71
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• 1998

This study uses [the instrument of ageing anxiety] in order to find if a negative prejudice against the old affects the attitude toward sex of the aged. The result shows no significant relation between ageing anxiety and the knowledge of and attitude toward sex of the aged. However, it does show that the higher the ageing anxiety is, the lower the knowledge of sex and the more restrictive the attitude toward it. The knowledge of and attitude toward sex of the aged shows meaninggul changes after education. Nursing students who were educated come to have more knowledge about and are more open to it. This result supports the preposition of this study. As society grows older the endeavour to guarantee a high-quality life for the old is necessary and the old should be regarded as an entity which has its own characteristic desires. Especially for the old to enjoy a good life as a sexual being, the mystical barriers about sex and old age ought to be removed. In the future the old themselves may maintain sexual desires regardless of age and society will be required to correct its prejudice against the old having sex. Particularly nursing students, as an effort to provide the old with overall care, should examine the elderly's sexual desires in a physical, psychological, and social context and consider the normal sexual changes occuring during the aging process and finally integrate this information into their nursing plans. In order to fulfill this role successfully they should overcome their own prejudice and educate themselves about this particular problem. As the proportion of the old becomes bigger and the concern about the quality of their life grows, sex among the old will become more important in the nursing field. By putting an educational mediation programme into operation with nursing students and estimating the effect, this study supplies the foundation to activate new educational programmes. In short it tells us that education can be a practical method to confront the myth and conventions concerning sex among the aged.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.293-293
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• 2017

The objective of this study was to determine physicochemical changes in brown rice during ageing condition. Five varieties (Haiami, Ilpum, Daecheong, Jungwon, and Dasan1) of brown rice were stored at $35^{\circ}C$ for 8 weeks. Crude protein and lipid content, seed germination rate, fat acidity, tocol content, TOYO glossiness value, pasting properties, and composition of storage proteins were measured to evaluate its quality during storage. The isomers of tocols (tocopherol and tocotrienols) were quantified using HPLC system, and the pattern of variation in rice storage proteins was examined through electrophoresis of protein extracts. Seed germination rate decreased by 2.7 times, whereas the fatty acid value dramatically increased by 4.8 times after 8 weeks of storage. Toyo glossiness value of cooked milled rice considerably affected by storage period, and the pasting properties of milled rice were also influenced by storage. The final viscosity and breakdown value increased, but setback decreased during storage. In terms of storage protein, proportion of prolamin (14.3 kDa) and globulin (26.4 kDa) increased, whereas percentage of glutelin (34-39 kDa and 21-22 kD) decreased. Furthermore, the contents of total tocol and isomers decreased in stored brown rice.

• 한국연초학회지
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• 제17권2호
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• pp.126-138
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• 1995

To investigate the changes of physicochemical properties of leaf tobacco during storage, cured leaves (both flue-cured(KF109) and burley(Burley 21) : 4 grades of leaves) were stored under the natural warehouse condition(room temperature) and processed leaves(both Rue-cured(NC82) and burly(Burley 21) : 6 grades of leaves) were stored at storerooms in tobacco processing plants(flue-cured Cheongju plant ; 2nd, 4th and 5th floor, burley : Kwangju plant ; 2nd floor, Chonju plant : 3rd and 5th floor). Tobacco leaves were sampled and analyzed every 3 months. Total sugar content of flue-cured leaf decreased slightly and the redness degree of leaf increased after 15 months' storage under the natural warehouse conditions. The pH of cured leaves were lowered both flue-cured and burley, and the decreasing rate of pH was large in flue-cured(0.24) as compared with burley(0.14). There was no significant differences of physicochemical properties of processed leaf among storerooms during 15 months' storage. The decreasing rate of processed leaf pH was somewhat large in flue-cured(0.26) as compared with burly (0.20), and in thick leaves as compared with thin leaves. The redness degree of flue-cured leaf increased slightly, while the degree of lightness and yellowness lowered slightly during storage. The lightness degree of burley leaf lowered slightly, too. The ageing process of cured leaf was similar to that of processed leaf, it is considered that the passing days after curing will be more reasonable than the passing days after processing for the establishment of proper ageing period.

• 한국의류학회지
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• 제22권2호
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• pp.193-202
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• 1998

The purpose of this study was to understand clothing condition of elderly men focusing on somatotype variation and satisfaction with ready-to-wear and to provide basic data in designing ready-to-wrar for the elderly men. The questionnaire method was used and one-to-one interviews were held for the elderly residents in Seoul, Deajon, Jonju, and Yeosu areas. The total of 275 questionnaires (from 148 elderly men in the 60's, 99 in the 70's and 28 in the 80's) were collected and used for statistics. SAS package was used for the statistics and the statistics were based on frequency, X2-test, ANOVA, Duncan's multifle range test. The results of the study were as follows; 1) Height (p< .05), weight (p< .001) and Rohrer index (p< .05) decreased significantly with ageing 2) The somatotypes of 75.6% were changed and the 70's 8t the 80's showed significantly (p< .05) higher changing rate compared to the 60's and more changes took place significantly (p< .001) with ageing. 3) The most preferred out wear was suit & tie and next was jumper or shirt. 4) For the mode of getting suit, the highest number 55.3%) purchased ready-to-wear, next (32.0%) was tailored and the least (12.7%) neither purchased nor tailored. The percentage of buying ready-to-wear significantly (p< .01) decreased with ageing. The main reason for getting tailor-made was not well fitting of ready-to-wear (20.7% out of 32.0%). And for the mode of getting suit, there was significant differance with income (p< .001) and pocket money (p< .01). 5) The most important factors in suit and shirt werefirst, size (fitness) and second, comfort in movement. 6) For the wearing feeling of suit, 55.3% showed discomfort. There was significant difference according to the age (p< .05) and pocket money (p< .05). The Discomfort increased with ageing and less pocket money. 7) 62.4% answered it uneasy to Pick out well fitting If comfortable suit. This showed their dissatisfaction with ready-to-wear. 8) As for the items of not well fitting, 64.4% answered in jacket, 60.8% in trousers, 46.0% in shirt. The above result shows that elderly men's somatotype changes as they age, suit is found uncomfortable and it's not easy for elders to pick out comfortable ready-to-wear. So, they seem to have a certain dissatisfaction in ready to wear. Therefore, there is a need for reorganization of size and developing pattern design according to measurement of elderly men.

• 대한기계학회논문집A
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• 제35권7호
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• pp.717-722
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• 2011

본 연구의 목적은 Al6061 의 T6 열처리 시 발생되는 잔류응력의 변화를 예측하는 것이다. Al6061-T6 의 일반적인 열처리 조건인 용체화처리($530^{\circ}C$, 2hr)와 인공시효($175^{\circ}C$, 9hr)에서 인공시효 시간에 따라 잔류응력 변화를 고려하였다. 잔류응력 예측은 열처리 실험을 수행하여 대류 열전달계수를 확보하고, 탄소성 모델로 가정한 유한요소해석을 적용하였다. 또한 인공시효와 같이 재료가 고온에서 장시간 유지되는 경우의 Zener-Wert-Avrami 함수를 적용하여 잔류응력 변화를 확인하였다. 잔류응력의 측정은 X 선 회절법으로 측정하고 측정결과는 예측된 유한요소해석 결과와 비교하여 해석의 신뢰성을 확보하고 해석기법을 확립하였다.

• 한국경제지리학회지
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• 제19권2호
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• pp.286-299
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• 2016

인구고령화 현상은 유럽, 일본 등 선진국에서 이미 경험하고 있는 일반적인 현상으로서 근본적으로 인구고령화 현상 자체를 문제시 하기보다 이 현상으로 파생되는 문제를 최소화하기 위한 정책적 노력이 필요하다. 다른 선진국과 비교해 볼 때, 우리나라의 인구고령화 속도는 급속도로 이루어지고 있고, 지역적으로도 상당히 다른 양상으로 전개되고 있는 특징이 있다. 즉, 인구고령화 속도는 세계적으로도 유례없는 경제성장과 더불어 가장 빠르게 고령화되고 있고, 도시화 과정에서 이촌향도의 인구이동 현상과 맞물리면서 도시지역보다 농촌지역의 인구고령화 현상이 더 빠르게 진행되고 있는 바 이 현상으로 파생되는 문제 또한 농촌지역이 훨씬 심각할 것으로 예상된다. 이러한 점에서 본 연구는 농촌지역 고령인구의 삶의 질과 직결되는 공공서비스 수준을 분석하되 공공서비스 수준의 지역적 차이를 분석하기 위하여 국지적 공간자기상관 분석기법을 적용하였다. 분석결과, 고령인구가 집중되어 있지만, 정작 고령자들에게 요구되는 공공서비스가 부족한 지역들이 지역적으로 차이 나게 분석되었다. 향후 인구고령화는 모든 공간정책 분야에서 중요한 인자로서 작용할 수 있다. 특히, 공공서비스 설치와 관련하여 효율성 측면에서 늘 소외되어온 농촌지역과 사회적 약자인 고령인구 등에 대한 정책적 배려가 확대되어야 하며, 농촌지역 고령자들의 삶의 질 제고를 위한 지역적으로 상이한 여건을 고려한 지역 맞춤형 공공서비스 설치 계획 등이 요구된다.