• Communications of the Korean Mathematical Society
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• v.32 no.2
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• pp.353-359
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• 2017

Starting from a t-norm T, it is possible to construct a class of new t-norms, so-called T-generalized t-norm. The purpose of this paper is to describe some properties of this class of generalized t-norms. An algebraic structure as well as a binary relation among t-norms are also investigated. Some open problems are discussed as well.

• Journal of Physiology & Pathology in Korean Medicine
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• v.34 no.1
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• pp.30-36
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• 2020

This study aimed to investigate heart rate variability (HRV) characteristics of cold pattern with repeated measurement data. Participants were taken from a Daejeon University cohort study from 2015 to 2018. Forty-seven of the participants studied displayed cold pattern while 23 showed signs of non-cold pattern. HRV was measured in supine position for 5 minutes at each year, and an 8-item cold pattern questionnaire was used for the diagnosis of cold pattern. SDNN (standard deviation of the NN intervals) and RMSSD (the square root of the mean squared differences of successive NN intervals) were used as time domain analysis, and TP (total power), VLF (power in very low frequency range), LF (power in low frequency range), HF (power in high frequency range), LF norm (LF power in normalized units), HF norm (HF power in normalized units) and LF/HF were used as frequency domain analysis. In the Mann-Whitney U test, LF norm, HF norm, and LF/HF showed differences between the cold pattern group and non-cold pattern group at every measurement, and in the independent t-test, the differences were also observed at three points except for the baseline (2015). In the repeated measures ANOVA, the interaction effects were not observed in all HRV parameters, but the time period effects were observed in SDNN, RMSSD, TP, VLF, LF and HF. There were significant differences between those two groups in LF norm, HF norm and LF/HF. This study suggests that LF norm, HF norm and LF/HF might be a useful indicator of cold pattern properties.

• Journal of the Korean Mathematical Society
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• v.56 no.1
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• pp.149-167
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• 2019

In this work, we study the existence, uniqueness and stability in the ${\alpha}$-norm of solutions for some stochastic partial functional integrodifferential equations. We suppose that the linear part has an analytic resolvent operator in the sense given in Grimmer [8] and the nonlinear part satisfies a $H{\ddot{o}}lder$ type condition with respect to the ${\alpha}$-norm associated to the linear part. Firstly, we study the existence of the mild solutions. Secondly, we study the exponential stability in pth moment (p > 2). Our results are illustrated by an example. This work extends many previous results on stochastic partial functional differential equations.

• Fashion & Textile Research Journal
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• v.17 no.6
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• pp.965-977
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• 2015

This study aims to investigate determinants that included personal values, pro-environmental beliefs, and proenvironmental norms for enhancing consumers' purchase intention of eco-friendly outdoor wear exploring Stern(2000)’s the value-belief-norm theory. A survey was conducted with females and males between the ages of 20 and 60 who have experienced buying outdoor wear products. A total of 300 responses were analyzed by descriptive analysis, factor analysis, a reliability test, an independent samples t-test, and regression analysis. The results of this study were as follows: 1) The results of exploratory factor analysis and reliability test on the personal value clearly showed factorial structures including the social power, ecologic value, openness, equality, and altruistic value. 2) There are significant differences in personal value sub-dimensions, pro-environmental beliefs, pro-environmental norm, and purchase intention of eco-friendly outdoor wear products according to respondents' gender and age. 3) Personal values, but not social power, affect pro-environmental beliefs; in turn, pro-environmental beliefs affect pro-environmental norms, which then affects purchase intentions of eco-friendly outdoor wear. The findings support the conclusion that there is significant causality among personal value such as ecologic, openness, equality, and altruistic, pro-environmental belief, and pro-environmental norm. This study suggests pragmatic implications to understand outdoor wear consumers' socio-psychological and demographic factors and to augment purchase intentions of eco-friendly outdoor wear products.

• Journal of Korean Academic Society of Home Health Care Nursing
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• v.29 no.1
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• pp.82-92
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• 2022

Purpose: The purpose of this study was to investigate the factors affecting the prevention behavior of COVID-19 infection among nursing students. Methods: This survey was conducted from September 3 to October 2, 2021 among 172 sophomore and senior students at universities in D metropolitan city and J province. The data were analyzed using descriptive statistics, t-test, ANOVA, Pearson's correlation and Hierarchical Regression. Results: There were significant differences in COVID-19 preventive behavior by gender (t=0.13, p=.017) and clinical practice experience (t=2.78, p=.006). COVID-19 preventive behavior showed significantly positive correlations with subjective norm (r=.35, p<.001), self-efficacy(r=.33, p<.001), and intention(r=.62, p<.001). The variables affecting COVID-19 preventive behavior were intention(β=.529, p<.001), subjective norm(β=.169, p=.008), and clinical practice experience(β=.118, p=.049), and the explanatory power was 43%. Conclusion: Considering these results, it is necessary to develop strategies that can encourage the intention of nursing students to practice prevention for COVID-19 infection control. In addition, maintaining subjective norms through national policies is a critical strategy.

• Child Health Nursing Research
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• v.25 no.1
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• pp.1-8
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• 2019

Purpose: This study was conducted using the theory of planned behavior to analyze factors influencing mothers' intention to vaccinate their children against hepatitis A (HA). Methods: This descriptive study used a questionnaire. The participants were 100 mothers with children under 19 years. The collected data were analyzed by the t-test, analysis of variance, and the Mann-Whitney U test. The Pearson's correlation was used to test the correlations among variables. Stepwise multiple regression was used to identify factors related to HA vaccination intention. Results: The attitude of mothers with children under 19 to HA vaccination were quite positive (6.2 of 7), and their perceived behavioral control (5.73 of 7), subjective norm (5.54 of 7), and vaccination intention (5.96 of 7) were relatively high. Attitude toward HA vaccination was the strongest influencing factor, followed by subjective norm. The explanatory power of attitude and subjective norm for HA vaccination was 84%. Conclusion: HA vaccination is very important for preventing HA. Mothers' positive attitudes toward HA vaccination were an important factor influencing their children's HA vaccination. Providing education on the benefits of HA vaccination and the vaccination schedule may foster positive attitude toward vaccination.

• The Journal of Korean Obstetrics and Gynecology
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• v.29 no.3
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• pp.10-22
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• 2016

Objectives: The aim of the study was to investigate the characteristics of the autonomic innervation of the heart in Precocious Puberty (PP) Girls.Methods: We studied 87 girls visiting Dongshin University Suncheon Oriental Medicine hospital from first Januarty 2013 to 31th December 2015. Among the 87 girls who were selected 14 people under the age of 8. The subjects were categorized in two groups, 2 PP girls and 12 healthy controls. We studied the difference of Heart rate variability (HRV) between two groups by Independent samples T-test using SPSS for windows (version 22.0).Results: The Standard deviation of all normal R-R intervals (SDNN), The spuare root of the sum of the spuare of difference between adjacent normal R-R intervals (RMS-SD) of PP group was non-significantly lower than non-PP group. Total power (TP), Very low frequency power (VLF), High frequency power (HF), Low frequency power (LF) of PP group was non-significantly lower than non-PP group, LF/HF ratio of PP group was significantly higher than non-PP group. Normalized high frequency power (HF norm) of PP group was non-significantly lower than non-PP group. Normalized low frequency power (LF norm) of PP was non-signficantly higher than non-PP group.Conclusion: The results suggest that imbalance of sympathetic and parasympathetic nervous system from girls of precocious puberty can be seen.

• The Journal of Korean Obstetrics and Gynecology
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• v.23 no.4
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• pp.155-163
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• 2010

Purpose: The aim of the study was to compare the characteristics of the autonomic innervation of the heart in polycystic ovary syndrome(PCOS) patients with regulary cycling controls. Methods: We studied 21 patients visiting $\bigcirc\bigcirc$hospital from 25th June 2009 to 25th June 2010. The subjects were categorized in two groups, 11 PCOS patients and 10 healthy regularly cycling controls. We studied the difference of Heart rate variability (HRV) between two groups by Independent samples T-test using SPSS for windows(version 17.0). Results: The Standard deviation of all normal R-R intervals (SDNN), The spuare root of the sum of the spuare of difference between adjacent normal R-R intervals (RMS-SD) of PCOS group was non-significantly lower than non-PCOS group. High frequency power (HF) and Normalized high frequency power (HF norm) of PCOS group was significantly higher than non-PCOS group. Normalized low frequency power (LF norm) of PCOS was signficantly lower than non-PCOS group. The results means increased sympathetic and decreased vagal modulation. Total power (TP), Very low frequency power (VLF) of PCOS group was non-significantly lower than non-PCOS group. Low frequency power (LF), LF/HF ratio of PCOS group was non-significantly higher than non-PCOS group. Conclusion: The results suggest that PCOS can be related to decreased activity of parasympathetic nervous system.

• Proceedings of the KIEE Conference
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• 2005.10b
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• pp.496-498
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• 2005

This paper presents intelligent digital redesign method of global approach for hybrid state space fuzzy-model-based controllers. For effectiveness and stabilization of continuous-time uncertain nonlinear systems under discrete-time controller, Takagi-Sugeno(TS) fuzzy model is used to represent the complex system. And global approach design problems viewed as a convex optimization problem that we minimize the error of the norm bounds between nonlinearly interpolated linear operators to be matched. Also by using the power series, we analyzed nonlinear system's uncertain parts more precisely. When a sampling period is sufficiently small, the conversion of a continuous-time structured uncertain nonlinear system to an equivalent discrete-time system have proper reason. Sufficiently conditions for the global state-matching of the digitally controlled system are formulated in terms of linear matrix inequalities (LMIs).

• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.10A
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• pp.943-951
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• 2006

Multi-input-multi-output (MIMO) systems are considered to improve the capacity and reliability of next generation mobile communication. However, the multiple RF chains associated with multiple antennas are costly in terms of size, power and hardware. Antenna selection is a low-cost low-complexity alternative to capture many of the advantages of MIMO systems. We proposed new joint Tx/Rx antenna selection algorithm with low complexity. The proposed algorithm is a method selects $L_R{\times}L_T$ channel matrix out of $L_R{\times}L_T$ entire channel gain matrix where $L_R{\times}L_T$ matrix selects alternate Tx antenna with Rx antenna which have the largest channel gain to maximize Frobenius norm. The feature of this algorithm is very low complexity compare with Exhaustive search which have optimum capacity. In case of $4{\times}4$ antennas selection out of $8{\times}8$ antennas, the capacity decreases $0.5{\sim}2dB$ but the complexity also decreases about 1/10,000 than optimum exhaustive search.