• Journal of KIISE:Information Networking
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• v.31 no.5
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• pp.519-531
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• 2004

Ad-hoc networks are temporary wireless systems composed of mobile nodes without any fixed infrastructure. The life time of each node in the ad-hoc network significantly affects the life time of whole ad-hoc network. A node which drained out its battery may incur the partition of whole network in some network topology The life time of each node depends on the battery capacity of each node. Therefore if all mobile nodes in the network live evenly long, the life time of the network will be longer. In this paper, we propose Power-Aware Dynamic Source Routing (PADSR) which selects the best path to make the life time of the network be longer. In PADSR, when a source node finds a path to the destination node, it selects the best path that makes nodes in the network live evenly long. To find the best path, PADSR considers the consumption of transmission energy and residual battery capacity of nodes upon the path. Consequently the network lives longer if we use PADSR.

• Journal of The Korean Society of Integrative Medicine
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• v.9 no.2
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• pp.35-41
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• 2021

Purpose : It is necessary to demonstrate the effect of non-invasive and non-pharmacological interventions such as manual therapy and therapeutic exercise for the management of nonspecific neck pain. In the present study, we aimed to investigate the efficacy of myofascial release therapy plus therapeutic exercise for disability owing to neck pain and quality of life in individuals with nonspecific neck pain. Methods : Eighteen participants with nonspecific neck pain were randomly allocated to intervention (n=9) and control groups (n=9). The intervention group received a myofascial release therapy for 20 min and performed neck stabilization exercises for 30 min twice a week for 4 weeks. The control group performed neck stabilization exercises for 30 min twice a week for 4 weeks at the same time points as the intervention group. Disability owing to neck pain and quality of life were quantified using the neck disability index (NDI) and the Korean version of the World Health Organization Quality of Life Brief Version (WHOQOL-BREF), respectively. NDI and WHOQOL-BREF were assessed before and after intervention. Results : The disability owing to neck pain significantly changed between the groups over time (total score of NDI, p=.049). There were significant time and group interactions in pain (pain intensity of NDI, p=.035) and concentration (concentration of NDI, p=.049). Personal care, lifting, reading, headaches, work, driving, sleeping, and recreation did not show significant improvement between the groups over time. Total score, overall quality of life and general health, physical health domain, psychological domain, social relationships domain, and environmental domain quantified by WHOQOL-BREF did not show significant improvements between the groups over time. Conclusion : These results suggest the clinical use of myofascial release therapy in addition to therapeutic exercise for the management of nonspecific neck pain. Further studies are needed to generalize the findings of this study.

• Korean Journal of Human Ecology
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• v.23 no.1
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• pp.149-161
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• 2014

The purpose of this study was to investigate the nutrition teachers' operation and demand of dietary life education in Jeonbuk Province. The study was carried out using a self administered questionnaire and the subjects were 190 nutrition teachers. The questions were general characteristics of the subjects, operating status as frequency, place, the main use time, and training demand on dietary life education by elementary school and middle & high school, teaching career, and training hours. The results are as follows. Most of the subjects were female(98.9%), more than half were 40's(52.1%) in their age, school work career was 13.2 years. Frequency of the dietary life education operation was once per month(56.8%), 2~3 times per month(27.9%), and place of education were dinning room (49.7%), classroom(25.9%). Almost of the subjects(90.4%) recognized the facilities for education was lack, 89.3% of them did the education materials was lack, also. The desirable frequency of dietary life education was once per month(48.9%), and once per week(35.3%.) The half of the subjects recognized the objects of the dietary life education was not only students but also their parents and teachers. The proper education time was dietary life education tim (34.2%), discretion activity time(31.1%). Most of the subjects(95.7%) had willing to get training, the proper training program was 30 hours, and they prefer summer vacation(61.0%) than winter vacation(30.5%) and semester(8.6%). Proper experimental practice ratio of environment : health : thanks were 30% : 43% : 27%. It is concluded that the demand of nutrition teachers is necessary for their education program in elementary and middle & high school.

• Proceedings of the KIEE Conference
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• 2000.07e
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• pp.40-43
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• 2000

Our studies diagnose insulation degradation using the method of computer sensing system, which has the advantages of PD(partial discharge) and AE(acoustic emission) sensing system. To use advantages of these two methods can be used effectively to search for treeing location and PD in some materials. In analysis method of degradation, using statically operator such as the center of gravity (G), the gradient of the discharge distribution(C), we have analyzed for the prediction of life which we can be obtained the time, occurred of many pulse of small discharge amplitude.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.05b
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• pp.297-300
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• 2006

Recently, To extend building's life, the use amount of repair mortar has been rapidly increased and naphthalenesulfonic and melanminesulfonic, polycarboxylic superplasticizer etc. are used for repair mortar in large numbers of construction site for efficient work. In this study, it was going to examine the use proper of superplasticizer for repair mortar through the hydrate setting time test and flow test with the mortar combination which replaced by alumina cement and added superplasticizer. As a result, the fluidity of the mortar replaced by alumina cement(10%) and added superplasticizer was dropped down and setting time was shortened. Especially this appearance was more increased on the mortar combination added ploycarboxylic and melanminesulfonic superplasticizer than naphthalensulfunic superplasticizer.

• Journal of Mechanical Science and Technology
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• v.20 no.3
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• pp.329-334
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• 2006

This paper presents the evaluation of LPG (Liquefied petroleum gas) regulators for home use. For the evaluation, several properties of the regulators were experimentally analyzed, such as the operation of safety device, the adjusting and lock-up pressure, the adjusting spring and the diaphragm, with respect to the used time of the regulators. Experimental results showed that the initial operation performances of regulators were degraded with increase of the service time and also showed that the degradation of the performance and material property could become serious after about six-year-use of the regulators.

• Journal of Welding and Joining
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• v.16 no.1
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• pp.70-76
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• 1998

Most fossil power plants and many critical components will be approaching the end of their nominal design life. At the same time, utilities are finding it economically attractive to extend the use of these plants for several more years, Especially Main steam pipe that operated under high temperature and pressure, often under the more severe operating conditions associated with cycling duty, is most important pipe system and critical component in fossil power plant. To extend the viability of older pipe system and to improve the operation and maintenance reliability, some technologies of precise diagnosis and life management have evolved out of the necessity. The purpose of this study is to descrive the related technologies and show the example of one power plants. The purpose of this study is to descrive the related technologies and show the example of one power plants. The stress analysis was done using ANSYS FEM Code. The branch area from main steam to turbine was the high stressed zone. To evaluate the degradation of the pipe material, replica, visual check, magnetic test, hardness test were done at the welding spot. The degradation level of welding point was E/F, so the remaining life of the welded area was about 0-25%.

• Archives of design research
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• v.21
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• pp.207-217
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• 1997

Mixed Use Area (Multifaceted Integration) is getting increasingly demanded since it has several merits such as preventing CBD from being emptied during night time, making daily life comfortable and utilizing the land more efficiently. However, the characteristic of Mixed Use Area -as advantages of it-, which is that it combines residence, retail, office, cultural, entertainment facilities altogether could be regarded as a weakness when it is viewed from each functions' original purposes such as residential and retail areas'. Accordingly, it is needed to do basic research and develop design guidelines of the Mixed Use Area to prepare its another take-off. The purpose of this research is to study theoretical background of Mixed Use Area's birth, understand its status quo by examining examples overseas and presented possible standardized ways of developing it.

• Korean Journal of Human Ecology
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• v.20 no.2
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• pp.311-325
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• 2011

The purpose of this study was to analyze patterns of time usage of the retired elderly so as to improve their quality of life. The subjects of this study were 225 elderly people in Jeonnam Province. The statistics used for data analysis were frequency, percentage, mean, standard deviation, t-test, and multiple regression. The major findings were as follows : (1) The retired elderly spend more time in physiological activities and leisure, and there was no day difference in time use. (2) On weekdays, the variables affecting labor time were age, former job, health state, and education. On the weekends, education, health state, and former job had significant effects on the amount of time spent on labor. (3) The variables affecting participation and volunteer time were: monthly living expenses, age, spouse, former job, and house, on weekdays, and on the weekends, significant factors were spouse, age, and former job. (4) The variables affecting leisure time were education, age, monthly living expenses, religion, and economic state, on the weekdays, and on weekends, the significant factors were education, economic state, house, religion, and former job.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.17 no.1
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• pp.1-16
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• 2018

Changes in the life style might vary trip purposes, ultimately leading to the change in the travel behavior. Therefore, this study analyzed the factors affecting travel time change by using the time use survey data in Seoul, surveyed by the Statistics Korea in 1999~2014. We developed multiple linear regression models for travel time, considering individual, household and time-related variables as independent variables. The models were separately estimated weekday and weekend. the model results show that the household, individual, and time related variables have an significant effect on the travel time. In addition, travel time is more influenced by individual characteristics thn household ones. Each activity time positively affects the travel time, indicating that travel is derived demand. The variable that have the greatest influence on the travel time is the activity time for leisure.