• Journal of the Korea Institute of Information and Communication Engineering
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• v.22 no.9
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• pp.1243-1249
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• 2018

In this paper, we propose a scheme that tunes the backoff period for enhancing the system throughput with estimating the number of devices in IEEE 802.15.4 slotted carrier sense multiple access with collision avoidance (CSMA/CA) networks. Since each device does not sense the channel always in IEEE 802.15.4 slotted CSMA/CA networks, a personal area network (PAN) coordinator is used to estimate the number of active devices. The PAN coordinator broadcasts an optimal backoff period for the estimated number of devices through a beacon frame. In order to estimate the number of devices in run time, a simple moving average filter is utilized. We show the performance of our proposed scheme in terms of the estimated number of devices and the system throughput. The simulation results show that our proposed scheme can obtain higher system throughput than the IEEE 802.15.4 standard.

• Journal of Korean Society for Atmospheric Environment
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• v.22 no.5
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• pp.554-563
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• 2006

Numerous epidemiological studies have shown stronger associations between $PM_{2.5}$ and both mortality and morbidity than $PM_{10}$. The association of $PM_{2.5}$ with respiratory mortality was examined in Seoul, during the period of $1996{\sim}2002$. Because $PM_{2.5}$ data were available for only 10% of this time period, a prediction regression model was developed to estimate $PM_{2.5}$ concentration. Death count due to respiratory-related diseases(total respiratory mortality; ICD-10, J00-J98) and death counts(cause-specific mortality) due to pneumonia(ICD-10, J12-J18), COPD(ICD-10, J40-J44) and asthma(ICD-10, J45-J46) were considered in this study. Averaged daily mortality was 5.6 for total respiratory mortality and 1.1 to 1.6 for cause-specific mortality. Generalized additive Poisson models controlling for confounders were used to evaluate the acute effects of particle exposures on total respiratory mortality and cause-specific mortality. An IQR increase in 5-day moving average of $PM_{2.5}(22.6{\mu}g/m^3)$ was associated with an 8.2%(95% CI: 4.5 to 12.1%) increase in total respiratory mortality The association of $PM_{2.5}$ was stronger for the elderly ($\geq$65 years old, 10.1%, 95% CI: 5.8 to 14.5%) and for males(8.9%, 95% CI: 2.1 to 11.3%). A $10{\mu}g/m^3$ increase in 5-day moving average of $PM_{2.5}$ was strongly associated with total respiratory mortality in winter(9.5%, 95% CI: 6.6 to 12.4%), followed by spring(3.1%, 95% CI: -1.2 to 7.5%), which was a different pattern with the finding in North American cities. However, our results are generally consistent with those observed in recent epidemiological studies, and suggest that $PM_{2.5}$ has a stronger effect on respiratory mortality in Seoul.

• The Journal of the Korea Contents Association
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• v.7 no.3
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• pp.140-151
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• 2007

In this study, we attempted to develop a watershed runoff index subject to main control points by dividing the Geum River basin into 14 sub-basins. The Yongdam multipurpose dam Daecheong multipurpose dam and Gongju gage station were selected to serve as the main control points of the Geum River basin, and the observed flow of each control point was calculated by the discharge rating curve, whereas the simulated flow was estimated using the Rainfall Runoff Forecasting System (RRFS), user-interfaced software developed by the Korea Water Corporation, based on the Streamflow Synthesis and Reservoir Regulation (SSARR) model developed by the US Army Corps of Engineers. This study consisted of the daily unit observed flow and the simulated flow of the accumulated moving average flow by daily, 5-days, 10-days, monthly, quarterly and annually, and normal monthly/annually flow. We also performed flow duration analysis for each of the accumulated moving average and the normal monthly/annually flows by unit period, and abundant flow, ordinary flow, low flow and drought flow estimated by each flow duration analysis were utilized as watershed runoff index by main control points. Further, as we determined the current flow by unit period and the normal monthly/annually flow through the drought and flood flow analysis subject to each flow we were able to develop the watershed runoff index in a system that can be used to determine the abundance and scarcity of the flow at the corresponding point.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2002.05a
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• pp.227-230
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• 2002

The Loose Part Monitoring System(LPMS) has been designed to detect, locate and evaluate detached or loosened parts and foreign objects in the reactor coolant system. In this paper, at first, we presents an application of the back propagation neural network. At the preprocessing step, the moving window average filter is adopted to reject the low frequency background noise components. And then, extracting the acoustic signature such as Starting point of impact signal, Rising time, Half period, and Global time, they are used as the inputs to neural network. Secondly, we applied the neural network algorithm to LPMS in order to estimate the mass of loose parts. We trained the impact test data of YGN3 using the backpropagation method. The input parameter for training is Rising Time, Half Period, Maximum amplitude. The result showed that the neural network would be applied to LPMS. Also, applying the neural network to the Practical false alarm data during startup and impact test signal at nuclear power Plant, the false alarms are reduced effectively. 1.

• Journal of Korean Public Health Nursing
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• v.10 no.2
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• pp.15-36
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• 1996

It is clear that the women's participation in social activity is dramatically increased in civilian field as well as military profession. Because of the characteristics of military nursing service, there are many difficulties. Frequent move, medical insurance, baby care. and the education are typical forms of difficulties for nurse officers in the military. The purpose of this research is to contribute to the perfect execution of nursing service. guarantee the active attitude for research and improve the combat strength by solving those private and economic problems. The method of research was analysis of question survey and the review of related literatures. The subject of research was 300 active nurse officers who work at the Army Hospitals. The survey was conducted 14 days from Oct 15 to Oct 28. The collected data was processed by computer using SPSS(Statistical Package of Social Science). Frequencies and percentages were used to examine the demographic characteristics of subject, and T-test was also used in the case of necessity. The result showed as follows; As the general characteristics of subject group; 28.7 years of average age, 73.6 months of service period, 63.4% of married. In regard of specialty; General 57.7%. Intensive Care 12.7% and Psychiatries 8.8%. The dissatisfactory factors about military welfare system were the difficulties in children education (36.9%). disadvantages on the civil medical insurance system (27.3%), and little chance of self education and development (21.5%). The problems in performing their duties were shown as dwelling instability due to frequent move (67.7%), and bring up children (14.2%). The reasons for resigning their job were shown as the instability of living status (64.2%), bring up children (18.8%) and dissatisfaction to the service (11.2%). The residential status was shown that military offered houses (45.2%), rental houses (29.3%) and own houses(14.64). The average numbers of moving residencies were; 3-4 time(34.6%), less than 2 times(33.1%), and 5-7 times(21.5%). Higher than 94.7% of the subject group spent more than 50.000 Won. In regard of education, they wanted to attend graduate school with their own expense(26.2%), computer science(20%) and Office Job Training(20%). The ways of taking care of children were mother-in-low(49.6%), mother(14.6%), and others(25%). The average expenditure per month for children were 20-30 hundred Won(44.2%), 10-20 hundred Won(25%) and 30-40 hundred Won(22.3%). The places of children care selected were public or occupational care center(56.2%), religious organization(20.8%), and other center managed by social organizations(10.4%). The result of survey for general welfare of nurse officers are as follows; By and large they seem to be satisfied with their job. however. there are some dissatisfactory factors. They are children care facilties, promotion. income. welfare facilities. disadvantage in medical insurance and civil hospitals. house purchase. unfair chances in specialty training. influence on promotion by educational status. and insufficient role for their children and husbands. As conclusion. the recommendations for improving nursing service are as follows; 1. Children care center managed by occupation 2. Dormitory system for children by military personnel 3. Equal opportunities in education according to ability 4. Reasonable moving price according to the distance and scope of family and extra allowance

• The Research Journal of the Costume Culture
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• v.22 no.4
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• pp.543-554
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• 2014

The purpose of this study was to find whether hemline cycles exist and whether hemlines show greater within-year variability over time. Utilizing US Vogue data from 1950 to 2013 on hemline length of women's daywear, total 2102 day-dresses or skirts on full fashion pictures were analyzed. The skirt length was divided by the total length of figure in the picture which was measured from shoulder to ankle. Aggregated yearly means smoothed by means of three-point moving averages were used to provide a better indication of the long-term direction of movement of the hemline. Within-year hemline variability was smoothed by the way of three-point moving average as well. The data showed five cycles on hemline change processes. The first cycle took 21 years from 1950 to 1971, which was the longest period and had the biggest hemline changes. The second cycle was the shortest from 1971 to 1977, in which hemline moved between below-knee length and midcalf. The hemline in the third cycle moved between midcalf and miniskirt. The third cycle took 16 years from 1977 to 1993. The forth was a short cycle from 1998 to 2001, and hemlines moved moderately between below-knee length and above-knee length. The fifth cycle has been on going since 2001, and the hemline has been getting longer after 2007. The within-year variability of hemlines was bigger in 1980s than previous years and was steadily increased.

• Journal of Oriental Neuropsychiatry
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• v.34 no.3
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• pp.181-212
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• 2023

Objectives: To examine the efficacy and safety of cupping therapy for insomnia disorder and provide clinical evidence that could contribute to further research. Methods: We searched randomized controlled trials (RCTs) that verified effects of cupping therapy for insomnia disorder from 11 domestic and foreign databases. Included studies were evaluated using Risk of Bias (RoB). Results: Nineteen RCTs were selected. Wet cupping was more frequently used than dry cupping. Moving cupping was mostly used among dry cupping methods. Dry cupping was mainly performed in Bladder Meridian on the back. Wet cupping was mainly performed on BL18, LR14, and BL15. The most common treatment period was 4 weeks. The average number of treatments per week was about 2.4 times for all types of cupping, about 3.2 times for dry cupping and about 1.9 times for wet cupping. All selected studies showed a significant sleep improvement compared to the control group. As a result of the meta-analysis, in terms of effective rate, SAS score, and SDS score, the wet cupping in combination with acupuncture was significantly more effective than acupuncture alone, although the quality of selected RCTs was low. Conclusions: Cupping therapy is effective for insomnia disorder. Based on results of this study, it is reasonable to use wet cupping two times per week on BL18, LR14, and BL15 or use moving cupping three times per week in Bladder Meridian on the back for 4 weeks to treat insomnia disorder.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.53 no.3
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• pp.188-195
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• 2004

This paper presents neural load torque observer that is used to deadbeat load torque observer and gain compensation by parameter estimator As a result, the response of the PMSM(permanent magnet synchronous motor) follows that nominal plant. The load torque compensation method is composed of a neural deadbeat observer To reduce the noise effect, the post-filter implemented by MA(moving average) process, is adopted. The parameter compensator with RLSM (recursive least square method) parameter estimator is adopted to increase the performance of the load torque observer and main controller The parameter estimator is combined with a high performance neural load torque observer to resolve the problems. The neural network is trained in on-line phases and it is composed by a feed forward recall and error back-propagation training. During the normal operation, the input-output response is sampled and the weighting value is trained multi-times by error back-propagation method at each sample period to accommodate the possible variations in the parameters or load torque. As a result, the proposed control system has a robust and precise system against the load torque and the Parameter variation. A stability and usefulness are verified by computer simulation and experiment.

• Journal of Electrical Engineering and Technology
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• v.10 no.2
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• pp.616-624
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• 2015

Flashover of power transmission line insulators due to contamination is a major threat to the reliable operation of power system. This paper deals with the analysis of leakage current characteristics of polymeric insulator using S-Transform technique in order to develop a better diagnostic tool to identify the surface condition of outdoor polymeric insulators. In this work, experiments were carried out on 11 kV silicone rubber insulator under AC voltage at different pollution levels. Moving average technique was adopted to find the trend followed by LC peak at different relative humidity conditions. S-Transform was used to find the relationship between energy and frequency content of the leakage current signal with respect to increase in pollution level over a period of time. From the S-Transform time-frequency contour analysis, point of transition to severe arcing due to increase in pollution and its thershold limit were evaluated. Reported results show that the surface condition of insulators could be easily identified from the S-Transform time-frequency analysis of leakage current signals.

• Magazine of the Korean Society of Agricultural Engineers
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• v.38 no.5
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• pp.64-73
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• 1996

When typhoon occurs, the meteorological conditions get worse and can cause a large damage from storm and flood . This damage, however, can be minimized if a precise analysis of the runoff characteristics by typhoon tracks is used in the flood contorl This paper aims at the analysis of storm occurrence and runoff characteristics by typhoon tracks in Nakdong river basin. Therefore, the data of 14 typhoons which invaded Nakdong river basin during the period from 1975 to 1991 were collected, analyzed, and studied. The major results of this study are as followings; 1) The frequency of the typhoon occurrence here in Korea was affected by the storms three times a year on the average. The highest-recorded frequency was during the months of July to September. 2) The survey of the track characteristics depending on the forms of the storm in the Nakdong river basin showed that typhoon storm advanced from the south of the basin to the north, while the frontal type storm was most likely to advanced from the west to the north. 3) Typhoon tracks are classified into three categories, 6 predictors with high correlation coefficient are finally selected, and stepwise multiple regression method are used to establish typhoon strom forecasting models. 4) The riview on the directions of progress of the storm made it clear that the storm moving downstream from upstream of the basin could develop into peak discharge for ca short time and lead to more flood damage than in any other direction.