• Sleep Medicine and Psychophysiology
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• v.22 no.2
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• pp.64-69
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• 2015

Objectives: We investigated whether sleep behaviors, severity of insomnia and circadian typology are associated with quality of life among Gyeongsang National University (GNU) medical students. Methods: Questionnaires were distributed to 46 fourth-year students of GNU Medical School. The hospital anxiety-depression scale, insomnia severity index (ISI), morningness-eveningness questionnaire (MEQ) and WHO Quality of Life-BREF (WHOQOL-BREF) were used. Results: Quality of life in terms of physical health was associated with age, weekday total sleep time (TST), weekend TST, catch up sleep, depression, ISI score, and MEQ score. Quality of life in terms of psychological health was correlated to weekday and weekend TST, anxiety, ISI score and MEQ score. Sex, weekday TST, depression, and ISI score were revealed to influence the social aspect of quality of life, and weekday and weekend TST, and ISI score were associated with quality of life in terms of environment. Multiple regression analysis showed that better sleep quality predicted to a higher quality of life in terms of physical, psychological and environmental health, and eveningness was associated with a better quality of life in terms of physical and psychological health. Conclusion: It is concluded that physical, psychological, and environmental aspects of quality of life were associated with quality of sleep and that physical and psychological aspects of quality of life were related to eveningness in GNU medical students. Therefore, it is equally important to treat emotional problem as well as improve sleep quality.

• Proceedings of the KSR Conference
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• 2011.10a
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• pp.1715-1721
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• 2011

For an efficient railroad operations the demand forecasting is required. Time series models can quickly forecast the future demand with fewer data. As well as the accuracy of forecasting is excellent compared to other methods. In this study is proposed the intervention ARIMA model for forecasting methods of KTX passenger demand. The intervention ARIMA model may reflect the intervention such as the Kyongbu high-speed rail project second phase. The simple seasonal ARIMA model is predicted to overestimate the KTX passenger demand. However, intervention ARIMA model is predicted the reasonable results. The KTX passenger demands were predicted to be a week units separated by the weekday and weekend.

• Proceedings of the KIEE Conference
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• 1991.11a
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• pp.39-42
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• 1991

The Application of Artificial Neural Network(ANN) to forecast a load in a power system is investigated. The load forecasting is important in the electric utility industry. This technique, methodology based on the fact that parallel structure can process very fast much information is a promising approach to a load forecasting. ANN that is highly interconnected processing element in a hierachy activated by the each input. The load pattern can be divided distinctively into two patterns, that is, weekday and weekend. ANN is composed of a input layer, several hidden layers, and a output layer and the past data is used to activate input layer. The output of ANN is the load forecast for a given day. The result of this simulation can be used as a reference to a electric utility operation.

• Proceedings of the KIEE Conference
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• 2001.05a
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• pp.230-232
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• 2001

This paper presents a model for short-term load forecasting using multiple time-series. We made one-hour ahead load forecasting without classifying load data according to daily load patterns(e.g. weekday. weekend and holiday) To verify its effectiveness. the results are compared with those of neuro-fuzzy forecasting model(5). The results show that the proposed model has more accurate estimate in forecasting.

• Journal of Environmental Science International
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• v.31 no.8
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• pp.707-713
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• 2022

This study aimed to comprehensively analyze the usage characteristics of children's parks according to location in Gangneung-si. Weekday and weekend, gender, time of stay, and usage behavior according to age group were analyzed and a video analysis of unmanned camera data for park management was conducted. On the average, the use of children's parks during spring and autumn was more than twice that during summer, and the use rate of children's parks located in old central districts by elderly people was relatively higher than the use rate of those located in housing development district. Overall, the usage ratio (24.6%) by elderly people was high, and their usage ratio (31.3%) in the morning period from dawn was significantly high. Among the usage behaviors, the rate at which dogs walk was analyzed to be somewhat high. As the usage ratio by elderly people is high with diverse usage behavior, it is necessary to provide complex functions to children's parks in the future.

• 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.

• The Journal of the Korea Contents Association
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• v.15 no.11
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• pp.582-590
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• 2015

Road type classification and K-factors are important role when design of number of lane. In this study not only classifies road type and estimating of K-factor but also economic evaluation tries for feasibility verification. Road type analysis results, time of day traffic volume variation, weekend-factor and vacation-factor are large in recreation roads. Weekday traffic volume and weekend traffic volume are similar patterns in provincial roads. AADT is high and time of day traffic volume variation is small in urban roads. In this study compares with economic analysis that designing of number of lane between KHCM's K-factor and this study K-factor. Economic analysis results, designed roads by this study's K-factor reduce cost about 4,708 hundred million won. So this study's K-factor is economical on provincial 4 lane roads.

• Journal of the Korean Home Economics Association
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• v.48 no.6
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• pp.43-56
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• 2010

This study explored time-use patterns of young children and compared the patterns according to mother's employment status. Using 6718 time diaries of 3359 children under age 5, as reported by their mothers, this study examined (1) the proportion of children who spent time on certain activities and the amount of time they spent on each activity for a weekday and a weekend day and (2) the proportion and the amount of time that children spent with certain adults. Compared to children with unemployed mothers, children with employed mothers spent more time during weekdays in child care centers and less time sleeping. These children also spent more time on education during weekends. The proportionate and actual times children spent with various adults also differed by the mother's employment status. Those with employed mothers spent less time with their mothers and more time with other relatives or teachers on weekdays. These results indicate that maternal employment corresponds with differing timeuse patterns from children's early life stages.

• The KSFM Journal of Fluid Machinery
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• v.18 no.6
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• pp.81-85
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• 2015

The purpose of this study is to evaluate energy savings for inverter driving multi-stage centrifugal pump. Variable speed driving pump system has high efficiency compared with constant speed driving pump system. Because of difficulty to estimate operating efficiency of variable speed driving pump system, energy saving rates are used to replace operating efficiency. energy saving rates are calculated from pump input power and pump duty cycle. But another researches have used pump duty cycles of each season for energy saving rate. In this study, for estimating energy saving rate more high accuracy, pump duty cycles are measured for 1 year. pump duty cycles, depending on the season and be classified according to the weekday/weekend or during the week day. By this pump duty cycles, Energy saving rate is calculated appropriately.

• Journal of Korean Society of Transportation
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• v.32 no.4
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• pp.347-356
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• 2014

Passenger cars occupy about 74% among registered vehicles in Korea and the ratio of transportation mode sharing is approximately 60% in the passenger transport part. However, there is no statistics related to travel characteristics of passenger cars, and official statistics are estimated from O/D travel data. Thus, National Transportation DataBase Center in KOTI has attempted to construct various statistical data through Korea Vehicle Use Survey. Based on these data, Analysis of Variance (ANOVA) was conducted to investigate the differences in travel characteristics of each analysis group. As a result, all of the explanatory variables(weekday vs. weekend, metropolitan area vs. non-metropolitan area, male vs. female, commute time vs. other time, routine purpose vs. non-routine purpose) were found to be different across households. In addition, travel distances per trip of weekday, metropolitan area, male, commute time, and non-routine purpose are longer than the opposite variables. Also, the trip distances of small size(1 to 2 persons) households are shorter compared to large size(more than 5 persons) households.