• Journal of Families and Better Life
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• v.14 no.4
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• pp.249-262
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• 1996

To give additional assistance in education for family time use and time management a computer program based on the time-related theories was developed. For this purpose the study consisted of three main stages. First various theories of family time use time management strategies and household work time were investigated and the assumptions were suggested. Second the module for predicting family time use was designed and the program using the module was developed. Third to evaluate the program's benefits the program was used at introductory class of undergraduate course. As the results the sophisticated software program could be used as an educational instrument to help not only students but also individual and family member to become knowledgeable about managers of family time resource. furthermore this program could be useful for the educators and counselors to help individuals and households with time use problems.

• The Korean Journal of Food And Nutrition
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• v.25 no.1
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• pp.205-213
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• 2012

This study investigated the life cycle of menus and made suggestions on the appropriate time for when new menus should be developed. For this purpose, a total of 636 customers who visited 'T' Restaurant more than 25 times in the past three years were used for analysis. After estimating product life cycles based on sales and selling period, an empirical study was conducted. In terms of product life cycle, a growth stage was observed in the category of pasta and pizza in both stores A and B, whereas sales in the rice category stayed constant. Regarding trend in seasonal sales, a big difference was detected between the two stores. While store A was already in the decline stage of the life cycle in all menu categories, store B remained in the growth stage. In terms of menu life cycle, the product life cycle of long-lived products was observed in the pasta category in both stores A and B. While the pizza category was in the growth stage, the product life cycle of long-lived products was observed in the rice category. It is expected that the results of this study could be useful in development of new menus and product life cycle management to fulfill diverse customer needs in the dining-out business.

• Macromolecular Research
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• v.15 no.4
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• pp.315-323
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• 2007

The present manuscript deals with the prediction of the lifetime of NBR compound based rubber gaskets for use as fuel cells. The material was investigated at 120, 140 and $160^{\circ}C$, with aging times from 3 to 600 h and increasing $H_2SO_4$ concentrations of 5, 6, 7 and 10 vol%. Both material and accelerated acid-heat aging tests were carried out to predict the useful life of the NBR rubber gasket for use as a fuel cell stack. To investigate the effects of acid-heat aging on the performance characteristics of the gaskets, the properties of the NBR rubber, such as crosslink density and elongation at break, were studied. The hardness of the NBR rubber was found to decrease with decreasing acid concentration at both $120\;and\;140^{\circ}C$, but at $160^{\circ}C$, the hardness of the NBR rubber increased abruptly in a very short time at different acid concentrations. The tensile strength and elongation at break were found to decrease with increases in both the $H_2SO_4$ concentration & temperature. The observed experimental results were evaluated using the Arrhenius equation.

• Journal of the Korean Society of Food Culture
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• v.25 no.4
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• pp.410-415
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• 2010

Banchandeungsok is a book written by a person who lived in the Cheongju area located in northern Chungcheong Province. The literature is regarded as a useful source for showing types of local food in the 1910s, so it was purchased by the National Folk Museum in 2007. The writer categorized dishes described in the recipe section of the book into side dishes, snacks, rice cakes, drinks, and miscellaneous. Following this, each category was distinguished by the name of the dish, the main material, the side material, and the cooking method is presented in tables. Thus, the food culture of Chungcheong Province was arranged based on the above categorized contents. The material from the product and the outside which grow spontaneously divided with the product which flows. The case which is a product the outside, went through what kind of process and could flow toward Sangshin village in Cheongju area probably, to observe tried. The area and time were clear Eumsikdimibang and Gyuhapchongseo Jusigui with comparisons. So tried to observe the time of 1910's Cheongju area culture Dietary life time and a regional feature.

• Structural Engineering and Mechanics
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• v.75 no.4
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• pp.455-464
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• 2020

Reinforcement corrosion is one of the major problems in the durability of reinforced concrete structures exposed to aggressive environments. Deterioration caused by reinforcement corrosion reduces the durability and the safety margin of concrete structures, causing excessive costs in managing these structures safely. This paper aims to investigate the effects of reinforcement corrosion on the load bearing capacity deterioration of the corroded reinforced concrete structures. A new analytical method is proposed to predict the crack growth of cover concrete and evaluate the residual strength of concrete structures with corroded reinforcement failing in bond. The structural performance indicators, such as concrete crack growth and flexural strength deterioration rate, are assumed to be a stochastic process for lifetime distribution modelling of structural performance deterioration over time during the life cycle. The Weibull life evolution model is employed for analysing lifetime reliability and estimating remaining useful life of the corroded concrete structures. The results for the worked example show that the proposed approach can provide a reliable method for lifetime performance assessment of the corroded reinforced concrete structures.

• Proceedings of the KIEE Conference
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• 2006.07a
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• pp.498-499
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• 2006

Oil-filled transformer technology has been around more than 100 years. The principle of operation in the same today as it has been for the previous decades. But all transformers have their life so it is important to know their useful life and the time for replacement. This paper will address this issue and provide the distribution transformer oil aging test results. Distribution transformer and laboratory specimens were externally heated to their respective maximum temperatures. Sample of oil and paper were removed at convenient intervals for testing. We believe that the results of this study will show the possibility of assessing the life of transformers.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1999.04a
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• pp.305-312
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• 1999

This study is intended to propose a systematic and practical life cycle cost(LCC) model for the development of the reliability-based seismic safety and cost-effective performance criteria for design and upgrading of long-span PC bridges. The LCC models consist of five cost functions such as initial cost, repair/replacement cost, human losses, road user cost, and indirect losses of regional economy. The proposed model Is successfully expressed in temrs of Park-Ang damage indices and life cycle damage probability obtained from SMART-DRAIN-2DX which is an existing algorithm for nonlinear time history analysis. The proposed LCC model is successfully applied to a viaduct constructed by PSM, in Seoul. Based on the observations, the proposed systematic procedure for the formulation of LCC model may be useful for the development of the reliability-based seismic safety and cost-effective performance criteria for design and upgrading of long-span PC bridges.

• Journal of Microbiology and Biotechnology
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• v.23 no.6
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• pp.750-758
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• 2013

Anthrax is a bacterial disease caused by the aerobic spore-forming bacterium Bacillus anthracis, which is an important pathogen owing to its ability to be used as a terror agent. B. anthracis spores can escape phagocytosis and initiate the germination process even in antimicrobial conditions, such as oxidative stress. To analyze the oxidative stress response in B. anthracis and thereby learn how to prevent antimicrobial resistance, we performed protein expression profiling of B. anthracis strain HY1 treated with 0.3 mM hydrogen peroxide using a comparative proteomics-based approach. The results showed a total of 60 differentially expressed proteins; among them, 17 showed differences in expression over time. We observed time-dependent changes in the production of metabolic and repair/protection signaling proteins. These results will be useful for uncovering the metabolic pathways and protection mechanisms of the oxidative response in B. anthracis.

• Journal of the East Asian Society of Dietary Life
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• v.25 no.3
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• pp.460-473
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• 2015

This study aimed to create a standardized recipe using three cultivars of tomatoes (Chal-tomato, Daejeo-tomato, Blacktomato) and select an appropriate tomato for producing tomato Jangajii through quality and sensory evaluation. With regard to the proximate composition of tomato Jangajii, moisture and ash contents of Chal-tomato were highest in the early stage of storage, whereas moisture, crude protein and ash contents of Black-tomato were highest in the final stage of storage. Daejeotomato showed minimal changes in pH, but showed the highest salt and sugar contents. L value increased with increasing storage time and then decreased thereafter (p<0.001). The a and b values decreased with increasing storage time and then increased thereafter (p<0.001). The reducing sugar content increased with increasing storage time and then decreased thereafter (p<0.001). With regard to Daejeo-tomato, hardness was the highest (p<0.001), and total microbial counts were lowest (p<0.001). Daejeo-tomato showed the lowest activities of PME as a softening enzyme and PG. For sensory properties, Daejeo-tomato showed a relatively high preference for all items except aroma. Based on the above results, Daejeo-tomato Jangajii showed superior quality characteristics and high preference in general among tomato Jangajii from all three cultivars of tomatoes. Therefore, Daejeo-tomato Jangajii is useful as low-sodium tomato Jangajii in light of quality characteristics and preference.

• Journal of the military operations research society of Korea
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• v.22 no.1
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• pp.114-128
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• 1996

In this paper, a life distribution fitting method based on generalized phase-type distributions(GPH) is presented. By fitting the life distribution to a GPH, we can utilize various useful properties of the GPH. Two different approaches are used according to the properties of the given failure time data. One is an approximation to a GPH through the piecewise Weibull failure rate(PWF) model and the other is a direct approximation to a GPH using the empirical distribution function. Two numerical examples are also presented. In the first example, both of the two approaches are utilized and compared for an incomplete data set. And in the second example, the direct approximation method from an empirical distribution is utilized for the analysis of a complete data set. In both cases, we could confirm the validity of the proposed method.