• Asian-Australasian Journal of Animal Sciences
• /
• v.15 no.6
• /
• pp.890-894
• /
• 2002

The accuracy of the gamma function to describe lactation curve of Yankasa ewes was investigated using milk production data obtained from 168 ewes with either complete or incomplete 84 day lactation records. Ewes were daily hand milked after over-night separation from lamb and thorough disinfection of the udder. The daily milk yield on the average was estimated from the weekly total yield. The effect of type of birth, parity, season of birth and lactation length on the components of lactation curve (a, b, c and s) were analysed by least-square procedures. All factors except parity significantly (p<0.01) influenced the curve parameters. The goodness of fit of the function did not differ between the two classes of varying duration of lactation; incomplete lactation however, showed a lower persistency and as expected lower level of production. Correlations ($r_p$) between lamb weight gain and milk yield using the weight records from lamb weighed at weekly intervals indicated a high and positive relationship in the early lactation that decreased in intensity as the lactation advanced.

• Journal of Families and Better Life
• /
• v.31 no.4
• /
• pp.97-111
• /
• 2013

The purpose of this study was to explore the typology of child care, investigate the characteristics of child care types, and analyze the differences in time deficit as well as time satisfaction by the types of child care for dual-earner couples with preschool children. The data source for this research was the 2009 Time Use Survey conducted by the Korea National Statistical Office. Dual-earners aged 20 to 59 years completed 1,568 time diaries, which were analyzed using chi-square, cluster analysis, and ANOVA analysis. Child care time was classified into three types in the three categories of child care, household work sharing and leisure sharing for both males and females respectively. Three types for husbands were named "vulnerable", "household work child care predominant" and "leisure predominant". The three types for wives were named "vulnerable", "household work child care oriented" and "household work child care". The characteristics of each type depended on age, education, weekly working hours, gender role of husbands and age, weekly working hours of wives. The vulnerable type of wives showed the highest level of time deficit. Based on the results, implications for Public policy on child care and various types of education as well as programs were suggested.

• Journal of Korean Academic Society of Home Health Care Nursing
• /
• v.25 no.2
• /
• pp.197-208
• /
• 2018

Purpose: This study investigated the smartphone using time, troubles with smartphone usage, and related factors in Korean adolescent smartphone users. Methods: Data were obtained from 54,603 subjects aged 13 to 18 years in the 2017 13th Korea Youth Risk Behavior Web-based Survey Results: The study analyzed the school type, academic achievement, residence type, weekly average allowance, and usual counselor, perceived stress, happiness, and depression of the subjects showed a significant difference in the variable of troubles experienced by the smartphone user. Multiple sample logistic regression analysis showed that adolescents with low academic achievement (weekday, weekend OR = 1.78, 1.65), low economic status (weekday, weekend OR = 1.17, 1.37), friends with distress counselors (weekday, weekend OR = 1.29, 1.24), weekly average allowance (weekday, weekend OR = 1.85, 1.50), stressed (weekend OR = 1.25), depressed (weekday, weekend OR = 1.26, 1.14), family troubles (weekday, weekend OR = 1.14, 1.15), friendship troubles (weekday, weekend OR = 1.70, 1.38), and academic performance troubles (weekday, weekend OR = 1.28, 1.38) spent more than the average using time on their smartphones. Conclusion: To prevent overdependence on smartphone use among adolescents, a nursing intervention program that relieves stress and lowers depression should be developed.

• Child Health Nursing Research
• /
• v.25 no.4
• /
• pp.507-517
• /
• 2019

Purpose: This study was conducted to examine the effects of team-based problem-based learning combined with smart education among nursing students. Methods: A quasi-experimental non-equivalent control group, pre-posttest design was used. The experimental group (n=36) received problem-based learning combined with smart education and lectures 7 times over the course of 7 weeks (100 minutes weekly). Control group (n=34) only received instructor-centered lectures 7 times over the course of 7 weeks (100 minutes weekly). Data were analyzed using the $x^2$ test, the Fisher exact test, and the independent t-test with SPSS for Windows version 21.0. Results: After the intervention, the experimental group reported increased learning motivation (t=2.70, p=.009), problem-solving ability (t=2.25, p=.028), academic self-efficacy (t=4.76, p<.001), self-learning ability (t=2.78, p<.001), and leadership (t=2.78, p=.007) relative to the control group. Conclusion: Team-based problem-based learning combined with smart education and lectures was found to be an effective approach for increasing the learning motivation, problem-solving ability, academic self-efficacy, self-learning ability, and leadership of nursing students.

• Journal of Astronomy and Space Sciences
• /
• v.37 no.2
• /
• pp.105-115
• /
• 2020

The Korean Institute of Technology Satellite (KITSAT-1) is the first satellite developed by the Satellite Technology Research Center and the University of Surrey. KITSAT-1 is orbiting the Earth's orbit as space debris with a 1,320 km altitude after the planned mission. Due to its relatively small size and altitude, tracking the KITSAT-1 was a difficult task. In this research, we analyzed the tracking results of KITSAT-1 for one year using the Midland Space Radar (MSR) in Texas and the Poker Flat Incoherent Scatter Radar (PFISR) in Alaska operated by LeoLabs, Inc. The tracking results were analyzed on a weekly basis for MSR and PFISR. The observation was conducted by using both stations at an average frequency of 10 times per week. The overall corrected range measurements for MSR and PFISR by LeoLabs were under 50 m and 25 m, respectively. The ionospheric delay, the dominant error source, was confirmed with the International Reference of Ionosphere-16 model and Global Navigation Satellite System data. The weekly basis orbit determination results were compared with two-line element data. The comparison results were used to confirm the orbital consistency of the estimated orbits.

• Research in Community and Public Health Nursing
• /
• v.31 no.1
• /
• pp.96-106
• /
• 2020

Purpose: This study aimed to examine the level of acculturative stress, career stress, social support and depression, and identify factors affecting depression among Korean international students in China. Methods: Data were collected from 157 Korean students studying in undergraduate, graduate, students exchange programs and language training courses in G university, J university, and S university in G city, Guangdong Province, China, from September 1 to October 27, 2017. The data were analyzed with descriptive statistics, t-test, ANOVA, and multiple linear regression. Results: The mean acculturative stress was 62.24±18.08 out of 165, whereas the mean career stress was 65.47±19.79 out of 125. The mean social support was 95.03±14.64 out of 125, and the mean depression score was 13.83±9.24 out of 60. The factor that had the greatest effect on depression among the participants was acculturative stress (β=.26, p=.001), followed by career stress (β=.24, p=.002), frequency of weekly phone calls with family (β=.19, p=.006), source of tuition payment (β=.18, p=.009), and self-perceived health (β=.15, p=.040). The model explained 33% of the variance. Conclusion: It is necessary to develop depression prevention and management programs as well as a customized health promotion program that account for the factors identified to have an effect on depression, namely, acculturative stress, career stress, frequency of weekly phone calls with family, source of tuition payment, and self-perceived health, and increase awareness of depression among international students.

• Atmosphere
• /
• v.27 no.3
• /
• pp.261-276
• /
• 2017

The main objectives of this study are to introduce Global Seasonal forecasting system version5 (GloSea5) of KMA and to evaluate the performance of ensemble prediction of system. KMA has performed an operational seasonal forecast system which is a joint system between KMA and UK Met office since 2014. GloSea5 is a fully coupled global climate model which consists of atmosphere (UM), ocean (NEMO), land surface (JULES) and sea ice (CICE) components through the coupler OASIS. The model resolution, used in GloSea5, is N216L85 (~60 km in mid-latitudes) in the atmosphere and ORCA0.25L75 ($0.25^{\circ}$ on a tri-polar grid) in the ocean. In this research, we evaluate the performance of this system using by RMSE, Correlation and MSSS for ensemble mean values. The forecast (FCST) and hindcast (HCST) are separately verified, and the operational data of GloSea5 are used from 2014 to 2015. The performance skills are similar to the past study. For example, the RMSE of h500 is increased from 22.30 gpm of 1 week forecast to 53.82 gpm of 7 week forecast but there is a similar error about 50~53 gpm after 3 week forecast. The Nino Index of SST shows a great correlation (higher than 0.9) up to 7 week forecast in Nino 3.4 area. It can be concluded that GloSea5 has a great performance for seasonal prediction.

• International Journal of Highway Engineering
• /
• v.20 no.3
• /
• pp.85-92
• /
• 2018

PURPOSES : In this study, analyze the characteristics of IOC indicator 'threshold' which is needed when evaluating the traffic signal operation status with ESPRESSO in various grade road traffic environment of Seoul metropolitan city and derive suggested value to use in field practice. METHODS : Using the computerized database program (Postgresql), we extracted data with regional characteristics (Arterial, Collector road) and temporal characteristics (peak hour, non-peak hour). Analysis of variance and Duncan's validation were performed using statistical analysis program (SPSS) to confirm whether the extracted data contains statistical significance. RESULTS : The analysis period of the main and secondary arterial roads was confirmed to be suitable from 14 days to 60 days. For the arterial, it is suggested to use 20 km/h as the critical speed for PM peak hour and weekly non peak hour. It is suggested to use 25 km/h as the critical speed for AM peak hour and night non peak hour. As for the collector road, it is suggested to use 20 km/h as the critical speed for PM peak hour and weekly non peak hour. It is suggested to use 30 km/h as the critical speed for AM peak hour and night non peak hour. CONCLUSIONS : It is meaningful from a methodological point of view that it is possible to make a reasonable comparative analysis on the signal intersection pre-post analysis when the signal operation DB is renewed by breaking the existing traffic signal operation evaluation method.

• Journal of the Korean Society of Food Culture
• /
• v.15 no.4
• /
• pp.259-268
• /
• 2000

The purpose of this study was to describe the levels of market goods substitution of housework and find out the determinants on it in the domain of food among married female home-based workers. The data were collected from 169 married female home-based workers in Pusan and Kyungnam province, by self-administered questionnaires. Frequencies, percentiles, Cronbach's alpha, Pearson's correlations, and multiple regression were used to analyze the data. In the convenience foods, frozen foods had the highest substitution level, whereas prepared stew had the lowest. The substitution level of Korean traditional storage foods was the middle. And in dining-out service, the substitution level was mostly high: the level of delivery service was higher than that of dining-out. Compared to the previous research, these results showed that market goods substitution tended to increase, and its level in the domain of food will promote continually over time. The variables affecting the substitution level of convenience food were the number of family members, occupation, the existence of elderly/disabled person in the family, sex-role attitude, and weekly hours at home-based work. The substitution level of Korean traditional storage foods was influenced by sex-role attitude, occupation, education, monthly household income, and the existence of elderly/disabled person in the family. The significant variables affecting the substitution level of dining-out service were weekly hours at home-based work, the number of family members, occupation, monthly household income, education, and sex-role attitude.

• Korean Journal of Cognitive Science
• /
• v.20 no.4
• /
• pp.535-554
• /
• 2009

Information collected on mobile devices might be utilized to support user's memory, but it is difficult to effectively retrieve them because of the enormous amount of information. In order to organize information as an episodic approach that mimics human memory for the effective search, it is required to detect important event like landmarks. For providing new services with users, in this paper, we propose the prediction model to find landmarks automatically from various context log information based on attributed Bayesian networks. The data are divided into daily and weekly ones, and are categorized into attributes according to the source, to learn the Bayesian networks for the improvement of landmark prediction. The experiments on the Nokia log data showed that the Bayesian method outperforms SVMs, and the proposed attributed Bayesian networks are superior to the Bayesian networks modelled daily and weekly.