• KSII Transactions on Internet and Information Systems (TIIS)
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• 제9권10호
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• pp.3965-3982
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• 2015

Event detection is one of the key issues in many wireless sensor network (WSN) applications. The uncertainties that are derived from the instability of sensor node, measurement noise and incomplete sampling would influence the performance of event detection to a large degree. Many of the present researches described the sensor readings with crisp values, which cannot adequately handle the uncertainties inhered in the imprecise sensor readings. In this paper, a fault-tolerant event detection algorithm is proposed based on Dempster-Shafer (D-S) theory (also called evidence theory). Instead of crisp values, all possible states of the event are represented by the Basic Probability Assignment (BPA) functions, with which the output of each sensor node are characterized as weighted evidences. The combination rule was subsequently applied on each sensor node to fuse the evidences gathered from the neighboring nodes to make the final decision on whether the event occurs. Simulation results show that even 20% nodes are faulty, the accuracy of the proposed algorithm is around 80% for event region detection. Moreover, 97% of the error readings have been corrected, and an improved detection capability at the boundary of the event region is gained by 75%. The proposed algorithm can enhance the detection accuracy of the event region even in high error-rate environment, which reflects good reliability and robustness. The proposed algorithm is also applicable to boundary detection as it performs well at the boundary of the event.

• 보건행정학회지
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• 제2권2호
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• pp.57-89
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• 1992

This study is aimed both to reorient the Health net-works focused to Health Subcenters in times of development of local autonomy in Korea and to collect the fundamental data such as attitude and practice of the directors of Health Subcenter. The materials are collected from 134 out of 258 sampling directors of Health Subcenters with a questionaire by mailing(respond rate 51.9%). The major findings of this fundamental data are as follows. 1. Current average number of outpatients cared by a director of Health Subcenter is found to be 21.6. 2. The directors of Health Subcenter have little deducted hours for Public Health Programme. 3. Number of the Preventive Health Programme worked by a director of Health Subcenter is from 0 to 3. The most major group worked only 1 programme marked at 69.4%. 4. The directors of Health Subcenter express approval opinin marked at 80.2% that their qualification to appoint has to finish intern course. 5. The average diagnosis allowance a month is approximately twenty hundred thousand won. 6. Most of Health Subcenter(market at 94%) adopted a self-supporting account system. 7. The most complaining subject of directors of Health Subcenter is their working environment. The second complaining subject is governmental officier's interference. 8. The average number of outpatients cared by a director of Health Subcenter is found to be certain differentials by their marriage and the duration of employment. Some proposals of development on Health Subcenter based on the result of this research is as follows : 1. The reorganization on Health Subcenter under line of National Health Center Net-work 2. The psychological reorientation of directors of Health Sucenter and officers. 3. Autonomy management of Health Subcenter. 4. Reorientation of status on directors of Health Subcenter.

• 보건행정학회지
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• 제28권1호
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• pp.53-69
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• 2018

Background: This study investigates association modified category medical specialization (CMS) and hospital charge, length of stay (LOS), and mortality among lumbar spine disease inpatients. Methods: This study used National Health Insurance Service-cohort sample database from 2002 to 2013, using stratified representative sampling released by the National Health Insurance Service. A total of 56,622 samples were analyzed. The primary analysis was based on generalized estimating equation model accounting for correlation among individuals within each hospital. Results: Inpatients admitted with lumbar spine disease at hospitals with higher modified CMS had a shorter LOS (estimate, -1.700; 95% confidence interval [CI], -1.886 to -1.514; p<0.0001). Inpatients admitted with lumbar spine disease at hospitals with higher modified CMS had a lower mortality rate (odds ratio, 0.635; 95% CI, 0.521 to 0.775; p<0.0001). Inpatients admitted with lumbar spine disease at hospitals with higher modified CMS had higher hospital cost per case (estimate, 192,658 Korean won; 95% CI, 125,701 to 259,614; p<0.0001). However, inpatients admitted with lumbar spine surgery patients at hospitals with higher modified CMS had lower hospital cost per case (estimate, -152,060 Korean won; 95% CI, -287,236 to -16,884; p=0.028). Inpatients admitted with lumbar spine disease at hospitals with higher modified CMS had higher hospital cost per diem (estimate, 55,694 Korean won; 95% CI, 46,205 to 65,183; p<0.0001). Conclusion: Our results showed that increase in hospital specialization had a substantial effect on decrease in hospital cost per case, LOS, and mortality, and on increase in hospital cost per diem among lumbar spine disease surgery patients.

• 한국식생활문화학회지
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• 제11권5호
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• pp.621-634
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• 1996

This study was conducted to investigate the eating patterns of Korean men by analyzing the relation among their socio-demographic characteristics, value toward food and nutrition, and eating behavior. Nine hundred twenty nine Korean men were selected by the stratified random sampling method. The socio-demographic characteristics of the subjects had a significant influence on their value toward food and nutrition. After in their sixties had meals for physiological needs rather than for nutrition or preference. Highly educated people, professional workers, office workers and people in the higher incomes, placed a higher value toward food and nutrition. In addition, rural inhabitants had a significantly lower value toward food and nutrition. They mainly ate to satisfy their hunger. The subjects' eating behavior had a significant difference according to their socio-demographic characteristics. The aged and the less educated valued breakfast the most, and showed a preference for rice as the staple food. The rate of skipping meals for this group was low. The higher their income, their eating behavior score was equally high, while the primary industrial workers and rural inhabitants had a low eating behavior score. Value toward food and nutrition had a significant influence on eating behavior. Those that placed a high value toward food and nutrition showed a marked tendency to choose bread or noodles rather than rice. In addition, those who placed a high value on food and nutrition skipped fewer meals and had a higher eating behavior score.

• Journal of Nutrition and Health
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• 제26권9호
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• pp.1129-1137
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• 1993

This study was carried out to analyze the effects of dietary and life-style factors on the prevalence of depression in Korea. Epidemiologic data from a nation-wide sample of 2,000 adults who were selected with the stratified random sampling method in Korea were interviewed by trained interviewers. Data were presented on the CES-D, a 20-items self-report depression symptom scale developed by the Center for Epidemiologic Studies in U.S.A. The prevalence of depression among all the respondents was 13.5%, with 13.1% in urban samples and 15.5% in rural samples. The prevalence was higher in females(15.3%) than in males(11.7%). There were highly marked differences in the prevalence of depression by sex(p<0.05), age(p<0.0001), education(p<0.001) and income(p<0.01). Respondents of 60 years and over group, the less educated group(below elementary school graduated), and the less income group(less than 400,000 won/month) reported the highest rate of depression. However subjects' occupation and residence had little relation with the prevalence of depression. Drinking and smoking habit appeared to be highly associated with depression in females(p<0.0001) but not in males. The prevalence of depression and eating behavior were highly related(p<0.005). Male respondents below 20 years, 20-29, and 60 years and over depressed group reported significantly lower energy and protein intakes compared to that of the normal group. However, in the female respondents 20-29 years and 60 years and over depressed groups showed the significantly lower energy and protein intakes compared to those of the normal groups(p<0.05), it can be concluded that the various ecological factors such as epidemiological, dietary, and health factors may affect the prevalence of depression among Korean.

• 한국콘텐츠학회논문지
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• 제9권6호
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• pp.399-406
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• 2009

이 연구는 중학생의 스포츠 활동 참가가 자아존중감에 미치는 영향을 규명하는데 그 목적이 있었다. 자아존중감에 영향을 미치는 요인을 스포츠 참가 빈도, 기간, 강도로 가정하고 이 요인들이 각각 자아존중감에 어떠한 영향을 미치는지를 분석하였다. 이러한 연구목적을 달성하기 위하여 본 연구는 2008년 현재 D시 지역에 소재하고 있는 중학교 재학생을 모집단으로 선정한 후, 유층집락무선표집법을 이용하여 420명의 표본을 추출, 최종 395명의 표본을 사용하였다. 사용된 조사도구는 설문지였으며, 통계 분석 방법은 빈도분석, 요인분석, 변량분석이였다. 이와 같은 연구방법 및 절차를 통하여 도출된 결과를 토대로 다음과 같은 결론을 얻었다. 첫째, 중학생의 스포츠 참가 빈도는 자아존중감에 영향을 미친다. 둘째, 중학생의 스포츠 참가 기간은 자아존중감에 영향을 미친다. 셋째, 중학생의 스포츠 참가 강도는 자아존중감에 영향을 미친다.

• 대한원격탐사학회지
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• 제23권6호
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• pp.529-536
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• 2007

불투수도는 도시화, 환경변화를 추정하기 위한 중요한 지수로서 도시 기후 변화, 홍수기철 도시 범람의 증가, 홍수 모델링에 영향 등 도시의 홍수 기상학과 수문학적인 변화와 매우 밀접한 관계가 있다. 본 연구에서는 안성지역 일대를 대상으로 하여 Landsat ETM+ 영상을 이용한 불투수도 작성을 시도하였다. 학습 및 검수자료는 고해상도 영상인 IKONOS 영상을 이용하였으며, Landsat ETM+ 영상에 대한 위성반사율을 이용하여 tasseled cap과 NDVI로 전환하고 다양한 변수들이 불투수도에 미치는 영향을 분석하였다. 그리고 Regression Tree 알고리즘에 따라 불투수도 추정식을 개발하여 지도화하였다.

• 한국기계가공학회지
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• 제18권9호
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• pp.29-35
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• 2019

The structure of the machinery industry due to the 4th industrial revolution is changing from precision and durability to intelligent and smart machinery through sensing and interconnection(IoT). There is a growing need for research on prognostics and health management(PHM) that can prevent abnormalities in processing machines and accurately predict and diagnose conditions. PHM is a technology that monitors the condition of a mechanical system, diagnoses signs of failure, and predicts the remaining life of the object. In this study, the vibration generated during machining is measured and a classification algorithm for normal and fault signals is developed. Arbitrary fault signal is collected by changing the conditions of un stable supply cutting oil and fixing jig. The signal processing is performed to apply the measured signal to the learning model. The sampling rate is changed for high speed operation and performed machine learning using raw signal without FFT. The fault classification algorithm for 1D convolution neural network composed of 2 convolution layers is developed.

• 지구물리와물리탐사
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• 제13권2호
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• pp.144-152
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• 2010

제주도 화산암 두께변화를 연구하기 위하여, 단주기와 광대역 지진계를 각각 8개와 4개 조사지 지표에 설치하여 상시미동 자료를 30 ~ 60분 동안 100 Hz 샘플률로 기록하였다. 인공잡음은 주간자료의 1.8 Hz 이상에서 나타나는 반면, 자연잡음은 0.4 ~ 0.8 Hz 범위에서 주간 및 야간 기록자료 모두에 기록되어 나타난다. H/V 스펙트럼비를 이용하여 구한 우세주파수는 0.2 ~ 0.7 Hz 범위에 분포한다. 우세주파수는 한라산 중심부로 갈수록 점진적으로 작은 값을 보여, 기존의 중력 및 자력모델의 결과처럼 제주도의 기반암이 섬 중심부 아래로 휜 구조임을 반영한다. 기반암 상부 현무암의 평균 횡파속도를 1,800 m/s로 가정할 경우, 각 조사지의 기반암 깊이는 약 640 ~ 2,140 m 정도로 평가된다.

• 한국학교보건학회지
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• 제20권1호
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• pp.103-111
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• 2007

Purpose : The purpose of this study was to investigate the effects of stresses to female university students and their habits of dealing with stresses through drinking alcohol and smoking. Methods : Subjects, 313 students, were selected through convenience sampling method from the 2 four-year universities in Chonbuk and Chonnam province from May to June, 2005. Data were collected through the structured questionnaires that include general characteristics, Quantity Frequency methods, the number of cigarette per day, campus stress scale, and stress coping style scale, and they were analyzed by Cronbach' alpha, descriptive statistics, ANOVA and t-test by using SPSS/PC⁺ program. Results: In this study, 80% of subjects have drunk alcohol. The mean frequency of drinking alcohol per month was 4.68 times and the mean number of alcohol consumption amount per drinking 6.16 glasses. The rate of smoking was 13.7%, and the mean number smoking cigarette per day in the previous month was 12.4. The mean score of stress was 2.20. Among 8 sub-factors of stress, study related stress scored highest among the sub-factors. The mean score of coping styles was 2.50. Among 4 coping styles, hopeful thought was mostly used. Among stresses, the concern of one's future affected her drinking habits. Faculty relationship, academic problem, and value affected smoking habits. Hopeful thought comes out to affect smoking, while drinking, perceived health status, and practice time showed no relationship with coping style. Conclusion: Based on the results, developing a life stress counseling program and effective coping program for women's university students is imperative, especially for those of who show passive attitude toward stress and solve it emotionally instead of using problem-oriented methods. Also, it will be necessary to study further nursing intervention to curb university females' drinking alcohol and smoking.