• 대한가정학회지
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• 제48권6호
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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.

• International Journal of Automotive Technology
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• 제6권4호
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• pp.333-340
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• 2005

In order to better quantify the contribution from nonroad sources to emission inventories, it is important to understand not only the emissions rates of these engines but also activity patterns that can be used to accurately portray their in-use operation. To date, however, very little information is available on the actual activity patterns of nonroad equipment. In this study, a total of 18 pieces of nonroad equipment were instrumented with collected data including intake manifold air pressure (MAP), exhaust temperature and, on a subset of vehicles, engine rpm and throttle position. The equipment included backhoes, compactors, dozers, motor graders, loaders and scrappers used in applications such as landfilling, street maintenance and general roadwork. The activity patterns varied considerably depending on the type of equipment and the application. Daily equipment operating time ranged from less than 30 minutes to more than 8 hours, with landfill equipment having the highest daily use. The number of engine starts per day ranged from 3-11 lover the fleet with an average of 5 starts per day. The average percent idle time for the fleet was approximately $25\%$ with a range from 11 to $65\%$ for individual pieces of equipment. Duty cycles based on exhaust temperature/throttle position profiles were also developed for two graders and one dozer.

• 한국환경보건학회지
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• 제37권2호
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• pp.94-101
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• 2011

Objectives: The purpose of this study is to evaluate the noise exposures of firefighters according to their time-dependent activity patterns. Methods: Personal exposure levels were measured for six days and nights using noise dosimeters; three days and nights for on-duty tasks, the other days and nights for off-duty activities. Results: The total amount of time spent in the workplace was 13,677 min (67%), outside areas 4,833 min (23%), in transit 1,002 min (5%), and other indoor area 807 min (4%) during a working period. However, during off-days they spent 10,858 min (76%) at home, 1,382 min (10%) outdoors, 1,225 min (9%) other indoors, and 493 min (3%) in transit. As a result of individual exposure levels, TWA did not exceed 90 dBA of the occupational exposure limit for the majority of the firefighters, whereas the levels of Lmax were 119 dBA, which were higher than the noise levels of firefighters in USA. Sometimes during dispatching the levels of Lpeak exceeded the ACGIH exposure standard (140 dBC). The Leq levels in transit were higher than the levels in home and other indoors even though the activity time is short. Conclusions: This paper characterized the noise exposure patterns of firefighters in Korea. We suggest that special noise sources, including sirens and speaker phones, should be readjusted to reduce noise exposure.

• 대한토목학회논문집
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• 제39권3호
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• pp.431-439
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• 2019

여의도 샛강은 1997년 국내최초 생태공원으로 조성된 이후 이용 활성화를 위한 다양한 노력이 투입되었음에도 불구하고 현재의 이용 현황은 인근 한강 공원과 비교했을 때 현저히 저조한 상황이다. 본 연구에서는 샛강 방문자 1,000명을 대상으로 면접 설문조사를 진행하였으며, 이용자들의 샛강에 대한 인식과 활동 패턴 등에 대해 조사하였다. 그 결과 전체 이용자 중 약 60 %가 도보를 이용한 인근 주민이었고, 대부분 가벼운 운동이나 산책을 하며 시간을 보내는 등 일반 서울시내 도시공원과 유사한 특성을 갖는 것으로 나타났다. 또한 다양한 통계분석을 통해 응답자 특성에 따른 샛강에 대한 인식과 활동 패턴 차이를 분석하였으며, 샛강에서의 활동 패턴이 샛강에 대한 만족도, 애착심, 참여의식 등에 미치는 영향에 대해 분석하고 고찰하였다.

• The Korean Journal of Ecology
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• 제20권1호
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• pp.9-14
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• 1997

Wintering behavior of mallards Anas platyrhynchos was studied from November 1995 to February 1996 at wintering habitats : Seosan reclaimed site, Oksan reservoir, and Kum river in Korea. The population of wintering mallards in maximum count was about 35, 000 at Sosan, 500 at Oksan and 1, 680 at Kum river, respectively. In Seosan area, mallards spent more time on water surface. In Kum river and Oksan reservoir, however, they spent more time in riversides. During the daylight hours, mallards spent more time in riversides and ground as the time passes by in the area. Behavioral patterns varied with habitat type, by days and months. Resting was a major time expenditure of mallards on water surface and riversides, and feeding occured occasionally on the ground. During the daytime, feeding and resting activities increased as time passed toward dusks However, time spendings for locmotion and comfort were decreased when it is close to the sun sets. Major disturbance factors within the habitats were identified the local traffics of humans, boats, aircrafts and motor vehicles. Among them, human was the most frequently affecting disturbance factor to the wintering mallards.

• PNF and Movement
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• 제15권2호
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• pp.177-183
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• 2017

Purpose: This study compared and analyzed the effect of the proprioceptive neuromuscular facilitation (PNF) arm extension pattern and leg flexion pattern on the contralateral lower extremity muscles when the patterns were applied to the same subject. Methods: In the study, 35 healthy men and women who understood the PNF patterns were selected as participants. The participants completed the PNF arm extension-abduction-internal rotation pattern and leg flexion-adduction-external rotation with knee flexion pattern in the supine position. While the patients' completed each pattern, the contralateral leg muscle activity was measured to examine the irradiation effect. The maximum isometric contraction time of the muscles to be measured was kept for 5 seconds, and the mean value was obtained by repeating the pattern three times. Results: When the leg flexion-adduction-external rotation with knee flexion pattern was completed, the muscle activity in the vastus lateralis, vastus medialis, biceps femoris, tibialis anterior, and gastrocnemius of the contralateral lower extremity was significantly greater than that found in the PNF arm extension-abduction-internal rotation pattern. Conclusion: The PNF leg flexion pattern showed greater muscle activity on the contralateral lower extremity than the arm extension pattern. Thus, the PNF leg extension pattern is more effective in the activation of the muscles associated with weight-bearing activity.

• 한국산업보건학회지
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• 제20권2호
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• pp.102-110
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• 2010

Personal exposure relies on characteristics of time activity patterns of the population of concern as human activities impact the timing, location, and level of personal exposure. The information about time spent in microenvironments plays a critical role for personal exposure to air pollutants. It is useful to determine the precise times of the day that the subjects are in certain locations or engaging in specific activities because exposure to some air pollutants can depend on temporal trends. This study investigated time activity pattern for workers of Korean population over 19 years old with 8,778 workers in weekday. The residential indoor times were 12 hours. Time activity was different by gender and the mean times stayed at home in weekday were 12.9 hours in female and 11.42 hours in male, respectively. The major factors on residential indoor time and workplace time were age, monthly income, occupation and industry type, work position, education, and gender. Considering shorter than those in other countries, Korean workers spent less time at home after the working hours. Determinants of time activity pattern need to be taken into account in exposure assessment, epidemiological analyses, exposure simulations, as well as in the development of preventive strategies. Since there are substantial difference of Korean worker activity pattern, this information can be critical for exposure assessment in Korea.

• 한국환경과학회지
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• 제29권1호
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• pp.109-117
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• 2020

Asthmatics are more susceptible to fine particulate matters (PM_2.5), compared to the general population. It has been reported that indoor PM_2.5 is mainly generated by combustion of fossil fuels, meat or fish In particular, asthmatics are known to be more susceptible to indoor PM_2.5 because 65~95% of child or adult asthmatics stay inside the house. Thus, understanding the association between indoor activity patterns and variations in indoor PM_2.5 levels is important. The purpose of this study is to determine the distribution of hourly indoor PM_2.5 concentrations in asthmatics' homes, and to evaluate its association with pan-frying cooking activity patterns, the most common PM_2.5 emission related activity. From November 2017 to February 2018, real-time PM_2.5 concentrations were measured in the living room of each asthmatic's house (n = 35) for three weeks at 1 minute intervals. At the same time, self-reported daily activity patterns, hourly proportion (%) of cooking activities, were also recorded every hour over three weeks for each patient. In this study, we provided quantitative evidence that the distribution patterns of indoor hourly PM_2.5 concentrations were associated with indoor cooking activities, especially in the homes of adult asthmatics. In addition, we observed that PM_2.5 emitted by pan-frying could maintain even over up to 2 hour lagtime.

• 한국축산식품학회지
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• 제38권1호
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• pp.14-25
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• 2018

Chemical compositions, trypsin inhibitory activity, and gelling properties of albumen from duck egg during salting of 30 days were studied. As the salting time increased, moisture content decreased, the salt content and surface hydrophobicity increased (p<0.05). Trypsin inhibitory activity and specific activity were continuously decreased throughout the salting time of 30 days (p<0.05). This coincided with the decrease in band intensity of inhibitor with molecular weight of 44 kDa as examined by inhibitory activity staining. Nevertheless, no differences in protein patterns were observed in albumen during the salting of 30 days. Based on texture profile analysis, hardness, springiness, gumminess, chewiness, and resilience of albumen gel decreased with increasing salting time. Conversely, salted albumen gels exhibited higher cohesiveness and adhesiveness, compared to those of fresh albumen. Scanning electron microscopic study revealed that gel of salted albumen showed the larger voids and less compactness. In general, salting lowered trypsin inhibitory activity and gelling property of albumen from duck egg to some extent. Nevertheless, the salted albumen with the remaining inhibitor could be an alternative additive for surimi or other meat products to prevent proteolysis.

• 대한가정학회지
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• 제46권2호
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• pp.113-125
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• 2008

In order to develop leisure activity programs, the responses of 900 middle and high school students to a questionnaire survey were analyzed. Between May 7 and May 21, 2007. we routinely interviewed adolescent (middle and high school) students from Daegu City. After initial screening, the responses of 874 students were used for statistical and descriptive analysis. The findings were as follows: 1) Respondents indicated the highest preference for 9-leisure activity programs, with physical training rating the highest. 2) Adolescent requirement for leisure activity programs varied according to demographic factors; sex, age, religion, family living standards level, monthly average allowance. 3) Adolescent requirement for leisure activity programs varied according to value disposition patterns; materialism and job achievement-oriented value disposition, human relationship-oriented value disposition, enjoyment-oriented value disposition. 4) Adolescent requirement for leisure activity programs varied according to leisure-constrains factors; social constrains, individual and time constrains, family constrains, economic constrains.