• Journal of Radiation Protection and Research
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• v.46 no.4
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• pp.178-183
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• 2021

Background: This study was carried out to provide environmental transfer parameter values to estimate activity concentrations of these radionuclides in agricultural crops when direct contamination occurred. Materials and Methods: Mass interception fractions (F_Bs) and weathering half-lives (T_ws) of ¹³¹I and radiocesium were calculated using openly available monitoring data obtained after the Fukushima Daiichi Nuclear Power Plant accident. F_B is the ratio between the initial radioactivity concentration of a radionuclide retained by the edible part of the plant (Bq·kg^-1 fresh weight [FW]) and the amount of deposited radionuclide in that area (Bq·m^-2). T_w values can be calculated using activity concentrations of crops decreased with time after the initial contamination. Results and Discussion: Calculated F_B and T_w values for ¹³¹I and radiocesium were mostly obtained for leafy vegetables. The analytical results showed that there was no difference of F_Bs between ¹³¹I and radiocesium by t-test; geometric mean values for leafy vegetables cultivated under outdoor conditions were 0.058 and 0.12 m²·kg^-1 FW, respectively. Geometric mean T_w value of ¹³¹I in leafy vegetables grown under outdoor conditions was 8.6 days, and that of radiocesium was 6.6 days; there was no significant difference between T_w values of these radionuclides by Wilcoxon rank sum test. Conclusion: There was no difference between ¹³¹I and radiocesium for F_Bs and T_ws. By using these factors, we would be able to carry out a rough estimation of the activity concentrations of ¹³¹I and radiocesium in the edible part of leafy crops when a nuclear accident occurred.

• Journal of Environmental Science International
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• v.30 no.8
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• pp.621-628
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• 2021

The characteristics of time changes in air temperature, DI (discomfort index) and WBGT (wet-bulb globe temperature) were investigated for inland city (daegu) and coastal city (pohang) of Gyeongbuk Province during the 2018 consecutive heat wave season. The time when the temperature dropped below 33℃ was around 19h in both regions. As such, the two regions were similar with respect to the time up to which the heatwave warning levels continued. However, the discomfort index (DI) was higher than 27 in Pohang. Most people feel unpleasant when an discomfort index of 27 or higher appears. The results indicated that Korea's night-time thermal environment during the summers is particularly poor in the southern coastal areas. WBGT began at 09:00 and lasted until 21:00, with a score of 31 or higher; this score, in principle, corresponded with the duration of outdoor activity in both regions. Therefore, it was found that outdoor work was at a level where all day long had to be stopped in both areas during the heat wave. Although time changes in temperature and WBGT were similar in both regions, Discomfort Index (DI) differed significantly. The difference refers to the fact that Pohang is strongly affected by the high heat capacity effect and the supply of water vapor from the sea.

• Journal of People, Plants, and Environment
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• v.23 no.5
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• pp.495-506
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• 2020

Background and objective: This study conducted a conjoint analysis on early childhood teachers to find out their preferences in horticultural activities that are used as a means of education in early childhood education. Methods: For the conjoint analysis, five attributes of horticultural activities were selected. Attribute 1 was method of horticultural activities, divided into two levels: exclusive and integrated horticultural activities. Attribute 2 was object of horticultural activities, divided into three levels: fruit crops, vegetable crops, and floricultural crops. Attribute 3 was activity type, divided into three levels: big and small group, free choice, and outdoor play. Attribute 4 was place for horticultural activities, and divided into two levels: indoors and outdoors. Attribute 5 was time for horticultural activities, divided into two levels: 30 minutes and 30-60 minutes. The orthogonal design was used to extract 20 profiles, after which we conducted a survey on 320 early childhood teachers and analyzed the valid responses from 257 teachers. Results: The preference of early childhood teachers showed highest importance in object (29.1%), followed by activity type (23.2%), activity method (17.4%), time (16.1%), and place (14.2%) (Pearson's R = .591, p = .008). By level of each attribute, the importance was high in exclusive horticultural activities for activity method, big and small group for activity type, vegetable and floricultural crops for object, indoors for place, and 30 minutes for time. Conclusion: The horticultural program preferred by early childhood teachers is comprised of big and small group activities using vegetable and floricultural crops, carried out indoors for 30 minutes as an exclusive class.

• Journal of Environmental Health Sciences
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• v.44 no.2
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• pp.143-152
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• 2018

Objectives: The purpose of this study was to provide basic data for air pollutant exposure modelling and understanding the contribution of respective microenvironments by assessing the time-activity patterns of Korean students according to variables such as grade, sex, weekday, and weekend. Methods: In this study, we compared the residential time of 521 (both weekday and weekend) lower elementary students, 1,735 (1,054 on weekdays, 681 on weekends) upper elementary students, 2,210 (1,294 on weekdays, 916 on weekends) middle school students, and 2,366 (1,387 on weekdays, 979 on weekends) high school students in different microenvironments according to grade, sex, weekday, and weekend. We used data from the 2014 Time-Use Survey by the Korean National Statistical Office for upper elementary students through high school students, and surveyed time-activity patterns of 521 lower elementary students aged 7-9 years. Each microenvironment was divided into indoor, outdoor, and transport. Indoor environments were divided into home, school, and other places. In addition, the results of previous studies were compared to this study. Results: Weekday time-activity patterns of Korean students indicated that lower elementary students spent $16.02{\pm}2.53hr$ in the home and $5.37{\pm}2.32hr$ in school. Upper elementary students spent $14.11{\pm}1.79hr$ in the home and $6.27{\pm}1.37hr$ in school. Middle school students spent $12.83{\pm}2.22hr$ in the home and $7.48{\pm}1.88hr$ in school. High school students spent $10.65{\pm}2.86hr$ in the home and $10.23{\pm}2.86hr$ in school on weekdays. High school students spent the least amount of time in the home and the most time in school compared to other grades Conclusions: Students spent most of their time indoors, including in the home, school, and other indoors. On weekdays, as the grade increases, home residential times were decreased and school residential times were increased. Differences in time-activity patterns according to sex were not found for either weekdays or weekends. It is estimated that Korean students could be affected by school indoor air quality. High school students could be most affected by school indoor air quality since they spent the most time at school.

• Journal of Families and Better Life
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• v.33 no.2
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• pp.149-164
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• 2015

In recent years, leisure time has received increasing attention in Korean society. Despite the growing interest, however, there are very few studies that explored shared leisure time, especially among married couples. In this light, the present study examined variations in shared leisure time by demographic characteristics and associations between shared leisure time and quality of marital relationship. We used the third wave of the national data KLoWF (Korean Longitudinal Survey of Women and Families, 9,997 19-64 years old women). The study sample included 5,965 married women with no prior history of divorce. Results showed that Korean wives reported very little shared leisure time with their husbands. Given that the mean of the shared leisure time reported by employed women was significantly lower than that of the un-employed, we speculated that the time constraint may be one of the major barriers to having leisure time with one's spouse among Korean married couples. Married women in their 30's had the most frequent couple leisure time. The younger wives in their 20s had more cultural leisure time with their husbands, but sharing outdoor leisure time was not related to their age. The higher level of education for women was associated with greater shared active leisure time. However, visiting a husband's family often took place regardless of the wives' education level. After controlling for age, years of education, job status and annual family income, shared active leisure time (i.e., cultural activity and exercise) was positively related to marital satisfaction. Visiting one's own family, however, was not considered a leisure activity for Korean wives. Rather, frequent family visits were related to lower marital satisfaction. Findings shed light on how leisure life of married women with spouses are intertwined with not only their socioeconomic status and but also marital relationship in culturally unique ways.

• Journal of Sport and Applied Science
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• v.4 no.1
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• pp.17-30
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• 2020

Moving sport tourism refers to travel that combines sport activity and tours to a particular destination. Although moving sport tourism is one of the fastest growing segments of the sport tourism industry, it is still lack of related-knowledge and academic studies. Hence, this study is conducted to explore the characteristics of moving sport tourism and to provide implications for sport tourism industry and future research. For this, ten participants who regularly participated in bicycle tours for the last 10 years were recruited for this study. The sample consisted of 9 males and 1 female. The average age of the participants was 44.6 years of which all but 2 had a full-time job. The average period of participating in bicycle tour was 7.9 years. For analysing data, content analysis approach was used. Interviews were tape recoded and data were multiple reviewed to identify the similar themes and to categorize them into conceptual constructs. Results suggest two requirements of moving sport tourism(moving and concurrent), three characteristics of moving sport tourism(self-directed, exploring, non-linear, purposive-riding, partial competitive, cultural touring) and two categories of moving sport tourism(full moving sport tourism and partial moving sport tourism). Implications for sport tourism industry and future studies were discussed.

• Journal of Yeungnam Medical Science
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• v.4 no.2
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• pp.139-148
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• 1987

The community health practitioners (CHP) play an important role in primary health care services to the underserved population in rural area. Time and motion study of 26 CHPs in Kyungpook Province was conducted through work diary method for 6 consecutive days from the time they arrived until they left the primary health post(PHP) during the past 3 weeks from November 16 to December 5, 1987. The allocation of activity time by working category, service category, location of activity and CHP's function was analyzed according to the characteristics of CHPs i. e., age, marital status and experience as CHP. The major findings are as follows : The mean activity time per CHP in a week was 2,918 minutes. The length of their working hours was longer for older, married and more experienced CHPs than others. About 80% of the CHP's activities took place within the PHP and only about 20% occured outside of the PHP. Working hours for the outdoor activities were longer for younger, single and less experienced CHPs than others. The allocation of activity time by working category showed 46.3% in the technical work and 18.7% in the administrative work. Working hours for the technical activities were longer for younger, single and less experienced CHPs than others. The percentage of activity time revealed greatest as much as 63.1% for direct patient care in technical work and 61.6% for record keeping in administrative work. Of the total working hours in a week, direct patient care and public health activities accounted for 29.2% and 16.2%, respectively. Of the indoor activities, working hours for direct patient care were longer than those for public health activities. However, of the outdoor activities, working hours for public health activities were longer than those for direct patient care. The allocation of activity time by CHP's function showed 49.7% in management of common disease, 31.8% in management of PHP and technical supervision of village health workers, 9.5% in MCH and family planning, 6.6% in community health management and 2.4% in community approach. Based on these findings, it was found that CHPs were mainly working in the PHP with a majority of their time being spent for direct patient care rather than preventive and promotive health cares. To enhance the preventive and promotive health services of the CHPs and to involve the activities for community development, refresher course for CHPs should be reinforced and supervision mechanism of the CHPs should be established and operated in Gun- and province-level.

• The Journal of the Korea institute of electronic communication sciences
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• v.12 no.6
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• pp.1233-1242
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• 2017

Various attempts have been made to prevent crime risk. One of the cases where outdoor pedestrians are attacked by criminals is the abnormal health condition. When a mental or mental condition that can not sustain normal walking due to drunkenness is exposed, the case of being a crime is revealed through crime case analysis. In this study, we propose a method for estimating the state of an individual that can be detected in outdoor activities. In order to avoid the inconvenience of installing a separate terminal for event information transmission of sensors and sensors, it is possible to estimate an abnormal state by using a 3-axis acceleration sensor built in a smart phone. The state of the user can be estimated by analyzing the momentum of the user and analyzing it with the passage of time. It is possible to distinguish the flow of time at regular intervals, to recognize the activity patterns in each time band, and to distinguish between normal and abnormal. In this study, we have evaluated the total amount of kinetic energy and kinetic energy in each direction of the acceleration sensor and the Fourier transformed value of the total energy amount to distinguish the abnormal state.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.22 no.2
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• pp.128-133
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• 2012

People are exposed to air pollution from a range of indoor and outdoor sources. Concentration of nitrogen dioxide $(NO_2)$, which is hazardous to health, can be significant in both types of environment. This paper reports on the measurement and analysis of indoor and outdoor $NO_2$ concentrations and their comparison with measured personal exposure in house and workplace indoors with 28 office workers during winter and summer seasons. Time activity patterns were used to determine the effects of these factors on personal exposure. The residential indoor and office indoor times were $12.29{\pm}1.58,$ $7.86{\pm}1.97$ hours in winter and $11.04{\pm}2.18,$ $8.26{\pm}2.04$ hours in summer, respectively. Measured residential indoor, outdoor and office indoor, personal exposure $NO_2$ concentrations were $23.10{\pm}8.46$ ppb, $23.97{\pm}6.86$ ppb, $21.91{\pm}11.50$ ppb, $22.08{\pm}8.64$ ppb in winter, and $19.94{\pm}6.04$ ppb, $21.21{\pm}6.84{\pm}$ ppb, $22.55{\pm}9.54$ ppb, $27.45{\pm}8.96$ ppb in summer, respectively. Contributions of residential and office indoor $NO_2$ concentration on personal exposure were estimated by 57.98%, 35.62% in winter and 37.38%, 28.97% in summer, respectively.

• Journal of Navigation and Port Research
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• v.30 no.3 s.109
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• pp.247-251
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• 2006

By becoming 21st century which run be charactered as highly industrialized society which spreads diversification and individualization, there have been elevation of income level and increase of time for leisure activity by introducing 5 working days system. And this brings out increasing of aquatic leisure activity population and the contents of the leisure becomes very active. Static indoor activity which was the main current of the leisure activity in the past, however, it is now called for outdoor activity accompanied by the society growth and even expands towards that people get into action and experience by their own free will. With this point of view, the aquatic leisure run become a safe activity. But with a rapid growth of aquatic leisure activity, safety concerns become a serious problem. To prevent safety accident, training should be given, safety inspection and registration should be requested, and strong support of system is needed so users can have an insurance for safety accident. These complements are necessary for overall nourishment and management measure to charge in systematical safety for the users.