• Korea journal of population studies
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• v.34 no.2
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• pp.45-64
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• 2011

This study examines changes and educational differences in parental time spent in childcare. Based on time diary data 1999-2009, it finds as follows. First, compared to 1999, parental time spent in childcare has increased in 2009. Unlike the tendency of convergence of time spent in childcare by sex in US, differences by sex have increased in Korea. Second, those who are highly educated tend to spend more time with children than their counterparts. For preschool aged children, parental time spent in physical care and playing has significantly increased by educational level. For school aged children, those who are highly educated are more likely than those who have lower level of education to help with children's study. Third, compared to 1999, time for leisure and economic activity has decreased in 2009 whereas time for commute, sleep, and care for others has increased.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.19 no.2
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• pp.215-223
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• 2021

The domestic CANDU nuclear power plants have been operated for a long time and various unforeseen spent fuel defects have been discovered. As the spent fuel defects are important factors in the safety of the nuclear power plant, a study on the analysis of the spent fuel defects to prevent their recurrence is necessary. However, in cases where the fuel rods inside the fuel assembly are defected, it is difficult to dismantle the fuel assembly owing to their welded structure and the facility conditions of the plant. Therefore, it is impossible to analyze the spent fuel defect because it is difficult to visually check the shape of the fuel defect. To resolve these problems, an analysis technology that can predict the number of defected fuel rods and defect size was developed. In this study, we developed a methodology for investigating the root cause of spent fuel defects using a database of the earlier fuel defects in the plants. It is anticipated that in the future this analysis technology will be applied when spent fuel defects occur.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.11
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• pp.1574-1580
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• 2009

To evaluate the effect of different housing systems on sow behavior, 80 gilts were randomly allocated at puberty to four treatments: i) sow stall in gestation followed by farrowing crate (SC), ii) group housing with individual feeding in gestation followed by farrowing crate (GC), iii) ESF (Electronic Sow Feeding) system in gestation followed by farrowing crate (EC), and iv) ESF system followed by group farrowing pen (EG). Behavioral observations were carried out on a total of 16 animals per treatment at the following stages: first day of allocation to housing treatment, day of service, 80 days after service, 109 days after service on entry to farrowing accommodation, 24 h before farrowing, day of farrowing, 14, 27 and 28 days after farrowing, at weaning. On each occasion, individual animals were observed for a 24 period with one minute time sampling. There were significant differences (p<0.001) between stages of the reproductive cycle for all the behavior patterns in all treatments. On the first day in experimental housing treatments, sows spent more time rooting and dog-sitting. Activity and investigatory behavior decreased as pregnancy progressed. An activity peak was apparent just before farrowing, followed by a high level of inactivity on the day of farrowing. Time spent active, eating and drinking increased as lactation progressed, and greatest activity and locomotion was seen immediately following weaning. There were significant differences between housing treatments (p<0.01) for standing, moving, eating, drinking, dog-sitting and lying. During pregnancy SC sows spent more time standing, rooting, drinking and dog sitting, while EC sows spent less time rooting and drinking and more time lying. During lactation, GC sows spent more time standing, moving and eating, less time dog sitting and lateral lying. Nursing frequency was reduced in GC sows (p<0.001). The maternal and piglet behaviors were influenced strongly by environment during lactation. However, it was also shown that previous housing history can influence the maternal behavior in the pre-farrowing stage and during early lactation.

• Journal of the Korean Home Economics Association
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• v.39 no.6
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• pp.25-40
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• 2001

The purpose of this study was to find out the amount of the household work time related to food and examine the factors affecting the time accomplished by married female home-based workers and on-site workers. The data were collected from 165 married female home-based workers, and 292 married female on-site workers in Pusan and Kyungnam province, by the self-administered questionnaire. frequency distributions, Cronbach's alpha, t-tests, Pearson's correlations, and multiple regression analyses were conducted by SPSS/PC+. The major findings of this study were as follows: (1) both married female home-based and on-site workers spent more time on household work related to food in a weekend than in a weekday, (2) in a weekday, occupation was significantly related to the amount of time that married female home-based workers spent on food household work, whereas age and occupation were significant for married female on-site workers, (3) on Saturday, the significant factors of the time spent on food household work were the number of family and occupation for married female home-based workers, and educational level, occupation, sex role attitude, existence of children of 6 years or under, and existence of elders/disability within the family for married female on-site workers, and (4) on Sunday, for married female home-based workers, the number of family, occupation, and the level of market good substitution had significant effects on the amount of time spent on food household work, and for married female on-site workers, age, the number of family, occupation, sex role attitude, work hours on Sunday, and the level of market good substitution were significant.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.1154-1157
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• 2003

The spent fuel slitting device is an equipment developed for the separation of the pellet and hull from the cutting fuel rod with length of 250 mm, and in order to feed UO$_2$ pellet. We have analyzed on the existing technologies for designing and producing of the slitting device in the first year(2001), based on these results, designed and produced the rod slitting device. It has effectively separated the pellet from the hull, but demanded the supplement separation work because of the mixing with pellet and hull in the vessel, and required the condition for the reducing time of the process. In the second year(2002), we have reduced the work time, performed the test and capacity evaluation with the improving device, based these results, and ensured the data demanded for designing of the spent fuel rod slitting device. We have compared with the DUPIC(Direct use of spent PWR fuel in CAND reactors) process, and developed the device for the purpose of reducing over 40 % in comparition with the DUPIC operation time(5 minutes). Based on these results, it will is effectively applied to available data for designing and producing of the hot test facility.

• Journal of the Korean Home Economics Association
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• v.34 no.5
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• pp.49-66
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• 1996

The purpose of this study is to identify how the households invest in their children as a human capital. In addition, contributing factors to households' human capital investment was examined. The results of this study are as follows; First, Average number of children 2 children of surveyed housewives, full time housewives had more time spent for children than working counterparts. The former spent 6.8 hours a day with the latter 4.98 hour a day while both of them shared the most time in nonphysical care of their children. meanwhile, money paid for children was that full time housewife family spent 1,014,000 and a working housewife family paid 974,000. Second, In the full time housewives, total amount of time housewives spend for their children was greatly influenced by the income, the age of the youngest child, and emotional value. The housewives' educational level, life cycle, and an income were a significant impact on money investment. Total investment was influenced by the housewives' educational level, life cycle, income, and the number of children.

• Asian-Australasian Journal of Animal Sciences
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• v.8 no.5
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• pp.477-480
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• 1995

The effects of formic acid and formaldehyde treatment and methionine supplementation to ladino clover fibrous residue silage on eating and rumination behaviour were studied in sheep. From the ladino clover fibrous residue, two silage were prepared, either untreated or treated with formic acid and formaldehyde. Four experimental diets: untreated silage, treated silage, untreated silage with supplementation of methionine and treated silage with supplementation of methionine, were offered to four sheep at a restricted level of DM intake (2% of BW/d) twice daily in a two-way layout design. Methionine supplementation with the treated silage significantly (p < 0.05) reduced daily time spent eating, and consequently, markedly increased rate of eating. However, there was little effect of methionine supplementation on the daily time spent eating and eating rate for sheep offered untreated silage. Methionine supplementation with the treated silage reduced daily time spent ruminating, although the same effect was not observed for untreated silage. The rumination index (time spent ruminating/100 g DM eaten) was remarkably smaller (p < 0.05) with methionine supplement in feeding treated silage, although it did not differ for sheep offered untreated silage. There were no clear effect of methionine supplementation on the rumination efficiency (i.e. number of chews/bolus, bolus time and rumination chewing rate) both feeding untreated silage and treated silage.

• Korea Journal of Hospital Management
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• v.13 no.4
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• pp.27-45
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• 2008

This research focused on a total of 378 patients with external injuries under the age of 14 who visited the emergency center at a university hospital in Korea, during the months of January, April, August and November between January and December of 2007. In addition, the survey was conducted only on even number days and ranged across the whole year to reflect the impact of seasonal characteristics on the collected data. The research focused on determining the characteristics and inflicting cause of these patients with external injuries, analyzed the total time spent in the emergency room and obtained the following results. 1. When classifying the patients into different genders, the proportion of males (67.5%) was higher than that of females (32.5%). According to the different age groups, the highest ratio, at 61.1 %, was patients under the age of six. 2. Looking at the total number of minutes spent in the emergency room, the longest amount of time occurred during April with 162.7 minutes, followed by 121.9 minutes in January and 92.4 minutes in November. August had the shortest period of time spent in the emergency room, a significant statistical difference from the other periods of the year (p<0.001). 3. Regarding the amount of time required for each examination, patients required to provide a urine test spent an average of 204.7 minutes while those who did not spent 113.5 minutes on average. This is a 5% statistical difference among the two groups (p>0.05). 4. Looking at the five most commonly diagnosed problems in the emergency room, the total number of people with these top five commonly diagnosed illnesses comprised 55.6%, or 210 patients out of 378. 5. Utilizing the Decision Tree Model to estimate the total number of minutes required per visit, the first classifications were made using a chemical examination factor. People subject to chemical classification spent an average of 177.7 minutes, which was longer than the overall average of 115.2 minutes, and those exempt from chemical examination spent an average of 103.8 minutes, which was shorter than the average Conclusion; Effort to curtail the total time spent in emergency rooms is vital in guaranteeing efficient management of hospitals and providing medical services. The delay experienced by many comprehensive professional medical centers must be resolved through the establishment of effective delivery of medical services, increased supply of patient rooms and other policy oriented implementations. However, for now, this problem must be resolved by increasing the level of patient satisfaction and guaranteeing effective operation of patient rooms, which will significantly contribute to the general management and success of hospitals and institutions.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.18 no.spc
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• pp.1-19
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• 2020

Based on the current high-level radioactive waste management basic plan and the analysis results of spent nuclear fuel characteristics, such as dimensions and decay heat, an improved geological disposal concept for spent nuclear fuel from domestic nuclear power plants was proposed in this study. To this end, disposal container concepts for spent nuclear fuel from two types of reactors, pressurized water reactor (PWR) and Canada deuterium uranium (CANDU), considering the dimensions and interim storage method, were derived. In addition, considering the cooling time of the spent nuclear fuel at the time of disposal, according to the current basic plan-based scenarios, the amount of decay heat capacity for a disposal container was determined. Furthermore, improved disposal concepts for each disposal container were proposed, and analyses were conducted to determine whether the design requirements for the temperature limit were satisfied. Then, the disposal efficiencies of these disposal concepts were compared with those of the existing disposal concepts. The results indicated that the disposal area was reduced by approximately 20%, and the disposal density was increased by more than 20%.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.10
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• pp.1417-1429
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• 2004

The objective of the paper was to study the drinking and other related behavior of dairy cows (Bos taurus). There were 142 Holstein dairy cows observed and compared in this study. The experiment was designed on the basis of two different housing systems (wet pad with forced ventilation cooling house and open house); two different seasons (winter and summer); four different stages (high milk yielding cows, low milk yielding cows, dry cows, and heifers); and grouping (home and visitor animals). All cows had free access to water. Dairy cows spent 13.8 min/day drinking in wet-pad house and 11.7 min/day in open house. owever, there was no significant difference in the duration of water drinking between these two housing systems (p>0.05). The water consumption was significantly higher in wet-pad housed animals (68 L/day) than open-housed animals (31.5 L/day) (p<0.05). A significant interaction between housing and grouping (p<0.05) was found. Home and visitor animals spent more time drinking in open house, wet-pad house, respectively. A highly significant interaction was found between housing and drinking time during the day (p<0.001). Animals in open house drank more during the morning (6:00 to 10:00 h), whereas wet-pad housed animals drank in the afternoon (14:00 to 15:00 h) and evening (18:00 to 20:00 h). The average time a cow spent in drinking in summer was not ignificantly different from that of drinking in winter. However, the water intake was significantly higher in summer (61.9 L/day) than in winter (38.6 L/day) (p<0.05). Drinking activity showed a highly significant interaction between season and physiological stage (p<0.01). High milk yield cows spent more time drinking in summer than in winter, whereas cows in all other stages followed the opposite drinking pattern. Grouping exchange did not influence the drinking behavior of dairy cows in either season (p>0.05); both home and visitor animals spent almost the same time in drinking water. A strong significant interaction between season and time during the day was found(p<0.01), suggesting that animal's high drinking frequency occurred during the daytime for both seasons, with a peak midday in winter and two peaks at 10:00 h in the morning and 19:00 h in summer. Thus, drinking behavior was associated with the cooler time of day in summer and with the warmer hours of day in winter. High and low milk yielding cows and heifers spent 15.3 min/day, 14.3 min/day, and 12.8 min/day, respectively, in water drinking activity, but there was no significant difference among them (p>0.05). There was, however, a significant difference in water drinking activity found in dry cows, which spent less time in drinking at 8.2 min/day (p<0.05).