• The Journal of Korean Institute of Communications and Information Sciences
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• v.24 no.7B
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• pp.1296-1304
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• 1999

In this paper, we propose an enhanced usage parameter control algorithm, which is one of the preventive traffic control method in ATM networks. Proposed algorithm is based on the cell loss priority bit in the ATM cell header. This algorithm can eliminate the measurement phasing problem in cell conformance testing in ATM networks. Proposed algorithm can minimize the cell loss ratio of high priority cell(CLP = 0) and resolve the burstiness of cells which may be introduced in traffic multiplexing and demultiplexing procedure. For the performance evaluation, we simulate the proposed algorithm with discrete time input traffic model, the results show that the performance of proposed algorithm is better than that of ITU-T usage parameter control algorithm.

• Journal of the Korean Institute of Intelligent Systems
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• v.21 no.5
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• pp.630-636
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• 2011

This paper is concerned with the stability analysis and stabilization for the Takagi-Sugeno(T-S) fuzzy systems with parametric uncertainties. To reduce conservativeness in stability analysis for T-S fuzzy systems, fuzzy Lyapunov functions are used. Stability analysis is performed and robust fuzzy controller is designed for stabilization of the system with parametric uncertainties. The stability and stabilization conditions are formulated in terms of linear matrix inequalities (LMIs). Finally, simulation example is presented to show the effectiveness of the proposed approach.

• Proceedings of the Acoustical Society of Korea Conference
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• autumn
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• pp.523-526
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• 2004

미숙련 작업자들에 의하여 생산되는 라우드스피커의 특성들을 분석하여 제작된 제품들의 품질 신뢰도를 분석하였다. 동일한 부품을 사용한 경우임에도 조립 제작과정에서 누적된 미확인 제작오차에 의하여 발생하는 스피커의 전기 임피던스와 음향응답특성등의 산포도를 분석하였다. 또한, 전기 임피던스 곡선들로부터 T-S 매개변수 규명법으로 규명한 스피커 매개변수들의 산포도도 분석하였다. 부품들의 질량에 대한 실측치와 매개변수법으로 규명한 결과를 비교하여 조립제작과정에서 이 값들의 변화 되는 정도도 분석하였다.

• Proceedings of The Korean Society of Health Promotion Conference
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• 2009.05a
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• pp.84-84
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• 2009

목적 : 청소년의 행태와 가족관계가 정신건강에 미치는 영향을 분석하여 중학생의 학교내외 생활지도 및 정신건강을 위한 프로그램 개발에 필요한 기본 정보를 제공하고자 함. 조사방법 : 원주의 한 남녀공학 중학교 3학년을 대상으로 2008년 11월 25일부터 12월 11일까지 설문조사를 실시함. 총 454명의 중학교 3학년 학생 중 377명이 조사에 참여하였음. 척도는 신체증상, 식사장해, 우울감, 대인관계, 무력감, 충동성 등 정신건강에 관한 6척도와 31개 항목으로 구성됨. 통계분석은 독립변수인 행태변수와 가족관계 변수를 교차분석을 시행하였고, 변수간의 평균간 차이검증은 t-test와 ANOVA를 시행하였고, 정신건강 관련요인 규명을 위하여 회귀분석을 실시함. 결과 : 성별에 따라 아침에 상쾌하게 눈이 떠지는지, 취침시각, 공부시간, 핸드폰 유무, 다이어트 경험, 운동 횟수, 취미여부가 통계적으로 유의하였음. 가족구성인원 변수에 따라 가족에게 고민상담, 집안 일 돕기가 통계적으로 유의하였음. 종속변수인 정신건강과 통계적으로 유의한 변수는 가족과 고민상담, 가족과 식사, 아침에 상쾌하게 눈이 떠지는지, 아침식사여부, 공부시간, 운동 횟수였음. 가족과 식사를 하는 학생들이 그렇지 않은 학생들보다, 그리고 12시 이전에 취침하는 학생들이 12시 이후에 취침하는 학생들보다 정신건강이 좋은 것으로 나타남. 토의 및 결론 : 중학생들의 정신건강 지도를 위해서는 행태변수와 가족관계 변수를 고려하는 것이 필요한 것으로 나타났음.

• Journal of the Korean Data and Information Science Society
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• v.21 no.6
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• pp.1041-1049
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• 2010

In Korean professional baseball, attendance is the largest source of revenue for development of professional baseball and the highest concern of professional baseball teams. So, if there is demand forecasting model, it will be helpful for pennant chasers to work out the strategies for drawing attendance. For this reason, this research intends to suggest the model which estimates Korean professional baseball's attendance and uses all usable variables which have an effect on attendance in limited circumstances. We supposed that dependent variable is attendance as well as several independent variables and error term are homoscedastic variance. And then, we compared the models which assume conditional heteroscedastic variance like GARCH and EGARCH with GARCH-t models which use the assumption that error term's distribution follows student-t distribution. In result of that, we could confirm that the models which were made by using GARCH(1,1)-t made estimates the most accurately among the several models considered.

• Journal of Korea Technology Innovation Society
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• v.19 no.3
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• pp.658-685
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• 2016

In technology economic theory, technology innovation through R&D is regarded as a core element of economic growth. This research analyzes how R&D input factor (R&D as a percentage of GDP, total number of researchers, the proportion of science and engineering degree) affects GDP, economic outcome variable, through mediating variable (S&T papers, patent registration). The most effective variable among R&D activity variables is following order: the number of S&T papers (0.967), the total number of researchers (0.373), the proportion of R&D expenditure (0.191), the number of patent registration (0.049), the proportion of science and engineering degree (0.007). It is that the proportion R&D expenditure and the total number of researchers shows greater indirect impact through S&T papers and patent than the direct impact on GDP. This implies the importance of high-quality human resources training and the necessity of maintaining the scale of R&D fund or the importance on GDP. Moreover, S&T papers turns out to have the greatest effect on GDP and implies new outcome and value by sharing and expanding new knowledge and technology created by R&D

• Journal of the Korean Society of Hazard Mitigation
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• v.10 no.4
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• pp.95-104
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• 2010

The storage function model is one of the most commonly used models for flood forecasting and warning system in Korea. This paper studies the physical significance of the storage function model by comparing it with kinematic wave model. The results showed universal applicability of the storage function model to Korean basins. Through a comparison of the basic equations for the models, the storage function model parameters, K, P and $T_l$, are shown to be related with the kinematic wave model parameters, k and p. The analysis showed that P and p are identical and K and $T_l$ can be related to k, basin area, and coefficients of Hack's law. To apply the storage function model throughout the southern part of Korean peninsular, regional parameter relationships for K and $T_l$ were developed for watershed area using data from 17 watersheds and 101 flood events. These relationships combine the kinematic wave parameters with topographic information using Hack's Law.

• Journal of Convergence for Information Technology
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• v.7 no.4
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• pp.205-213
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• 2017

This study was conducted to identify convergence factors affecting smoking behavior among college students through the lens of a Health Belief Model. A descriptive study was carried out with 417 college students in Jeju, South Korea. Descriptive statistics and multiple regression analysis were performed using the SPSS 19.0 program. The results showed that sex(t=-7.44, p<.001), pocket money(t=-2.06, p=.040), smoking in the family(t=4.43, p<.001), smoking of close friends(t=9.59, p<.001), and perceived barriers(t=0.87, p=.014), cues to action(t=6.33, p<.001) were statistically significant variables influencing smoking. These findings indicate that among smoking-related and health belief-related variables needs to be considered for preventive and therapeutic approach to stop smoking in college students.

• Journal of Industrial Convergence
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• v.20 no.10
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• pp.71-77
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• 2022

The purpose of this study was to identify factors affecting the mental health of female middle school students living in rural areas. The study period was from March 14 to 25, 2022, and was conducted with 239 female middle school students attending three middle schools located in G district. The collected data were analyzed using descriptive statistics, t-test, Pearson's correlation, and multiple regression. As a result of the study, significant influencing factors on the subject's mental health were living with both parents (β=.12, t=2.50, p =.013), past subjective mental health status (β=.15, t=2.83, p=.005), subjective physical health status (β=-.21, t=-3.94, p<.001), loneliness (β=.22, t=4.23, p<.001), and severity of insomnia (β=.36, t=6.55, p<.001), and these variables showed 46% explanatory power for mental health. Through this study, further research is needed to specify the causal relationship between living with both parents, past mental health status, physical health status, loneliness, and severity of insomnia and intervention strategies for the mental health of female middle school students considering these variables.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.12 no.4
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• pp.562-569
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• 2001

This paper presents the optimum design method for T-shaped microstrip-line-fed slot antennas on various substrates. Since the impedance bandwidth of the antenna depends highly on the vertical offset position and the length of horizontal strip conductor, we derived the formulas regarding these design parameters to get the maximum bandwidth. The formulas can compute the offset position and the length of horizontal strip conductor for any given substrate parameters. We compared the results obtained by using these design formulas and the one obtained by the simulation for each slot width, and it showed very good agreement.