• Advances in nano research
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• 제11권6호
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• pp.581-593
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• 2021

This model is proposed to describe the buckling behavior of Carbon Nanotubes (CNTs) embedded in an elastic medium taking into account the combined effects of the magnetic field, the temperature, the nonlocal parameter, the number of walls. Using Eringen's nonlocal elasticity theory, thin cylindrical shell theory and Van der Waal force (VdW) interactions, we develop a system of partial differential equations governing the buckling response of CNTs embedded on Winkler, Pasternak, and Kerr foundations in a thermal-magnetic environment. The pre-buckling stresses are obtained by applying airy's stress function and an adjacent equilibrium criterion. To estimate the nonlocal critical buckling load of CNTs under the simultaneous effects of the magnetic field, the temperature change, and the number of walls, an optimization technique is proposed. Furthermore, analytical formulas are developed to obtain the buckling behavior of SWCNTs embedded in an elastic medium without taking into account the effects of the nonlocal parameter. These formulas take into account VdW interactions between adjacent tubes and the effect of terms involving differences in tube radii generally neglected in the derived expressions of the critical buckling load published in the literature. Most scientific research on modeling the effects of magnetic fields is based on beam theories, this motivation pushes me to develop a cylindrical shell model for studying the effect of the magnetic field on the static behavior of CNTs. The results show that the magnetic field has significant effects on the static behavior of CNTs and can lead to slow buckling. On the other hand, thermal effects reduce the critical buckling load. The findings in this work can help us design of CNTs for various applications (e.g. structural, electrical, mechanical and biological applications) in a thermal and magnetic environment.

• 보건교육건강증진학회지
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• 제27권4호
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• pp.165-175
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• 2010

Objectives: The purpose of this study is to evaluate the program theory of a lifestyle intervention program for the prevention and treatment of metabolic syndrome. Methods: The program evaluated is a tailored intervention for multiple health behavior associated with metabolic syndrome which is informed by theoretical constructs from the Intervention Mapping and Transtheoretical model. The program components include one-to-one health counseling, a self-management handbook, and a health diary. To evaluate program impact theory we examined the logic of program goals and objectives, intervention methods and strategies, and the theoretical constructs of program materials through document review and matrix building. Results: This evaluation has found that the intervention program applied social cognitive theory constructs to design intervention methods and strategies in addition to the Transtheoretical model: self-monitoring for goal setting and monitoring skill, outcome expectation for the benefits of health behavior change, and interaction with environment for observational learning through modeling. While the intervention addresses multiple determinants and behaviors, it is limited to an individual level and lacks social and environmental approaches. Following the Transtheoretical framework, the contents of the intervention materials were developed utilizing consciousness raising as a main strategy for earlier stages of change, and counterconditioning and stimulus control for later stages of change. Conclusion: Program theory evaluation can be a process of enhancing program validity. It would also be necessary for providing basis for efficient program implementation. When comparisons of program theory between similar programs are possible, program theory and validity will be strengthened when comparisons of program theories between similar programs are possible.

• Steel and Composite Structures
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• 제36권5호
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• pp.521-531
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• 2020

The behavior variation of concrete dam is investigated, based on a new method for analyzing the data model of concrete dam in service process for the limitation of wavelet transform for solving concrete dam service process model. The study takes into account the time and position of behavior change during the process of concrete dam service. There is no dependence on the effect quantity for overcoming the shortcomings of the traditional identification method. The panel data model is firstly proposed for analyzing the behavior change of composite concrete dam. The change-point theory is used to identify whether the behavior of concrete dams changes during service. The phase space reconstruction technique is used to reconstruct the phase plane of the trend effect component. The time dimension method is used to solve the construction of multi-transformation model of composite panel data. An existing 76.3-m-high dam is used to investigate some key issues on the behavior change. Emphasis is placed on conversion time and location for three time periods consistent with the practical analysis report for evaluating the validity of the analysis method of the behavior variation of concrete dams presented in this paper.

• 한국자기학회지
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• 제8권4호
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• pp.179-184
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• 1998

일반적으로 페로브로스카이트 구조의 망간 산화물에서 많이 관찰되어온 초거대 자기 저항 현상은 임계점 (큐리온도) 부근에서 온도 변화에 의한 상자성-강자성 상전이와 동반한 전기 전도 기수 변화에 따른 급격한 저항 변화와 매우 밀접한 광계가 있다. 본 논문에서는 이러한 전기 저항-온도 거동을 모사하기 위해, 온도에 따른 상분율 변화 함수를 유효매질 이론(effective media theory)을 이용하여 모형식을 마련하엿다. 미 모형식은 실제 La0.7Ca0.3MnO3의 저항-온도 거동을 매우 정확하게 모사하였다.

• 지역사회간호학회지
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• 제13권3호
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• pp.456-470
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• 2002

Objectives: The purpose of this study was to test the Theory of Planned Behavior (TPB) in the prediction of smoking cessation intention and smoking cessation behavior among adolescent smokers, in order to provide basic data to develop a future smoking cessation program as a nursing intervention. Method: The study subjects were 80 adolescent smokers who had smoked one cigarette and attended a five-day school smoking cessation program. The data were collected from October 24 to December 21, 1999. The instruments used in this study were the tools developed by Jee (1994) to measure TPB variables such as attitude toward smoking cessation behavior, subjective norm, perceived behavioral control, smoking cessation intention, and smoking cessation behavior. The data were analyzed with the SAS/PC program using descriptive statistics, hierarchical multiple regression, and logistic multiple regression. Results: 1. Attitude toward smoking cessation behavior, subjective norm, and perceived behavioral control were partially significant in predicting smoking cessation intention. 2. Smoking cessation intention and perceived behavioral control toward smoking cessation behavior did not significantly predict smoking cessation behavior. 3. There were partial interaction effects among the attitude toward smoking cessation behavior, subjective norm, and perceived behavioral control in the prediction of smoking cessation intention. 4. There were partial interaction effects between smoking cessation intention and perceiver behavioral control toward smoking cessation behavior in the prediction of smoking cessation behavior. Conclusion: This study partially demonstrated support for the TPB model that was partially useful in predicting smoking cessation intention and smoking cessation behavior among adolescent smokers. Therefore, it is recommended that attitude toward smoking cessation behavior and perceived behavioral control should be considered in developing smoking cessation programs and implementing nursing interventions to change the smoking behavior of adolescent smokers.

• Journal of Power Electronics
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• 제14권6호
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• pp.1303-1313
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• 2014

Dynamic behavior of the harmonic detection part of an active power filter (APF) has an essential role in filter compensation performances during transient conditions. Instantaneous power (p-q) theory is extensively used to design harmonic detectors for active filters. Large overshoot of p-q theory method deteriorates filter response at a large and rapid load change. In this study the harmonic estimation of an APF during transient conditions for balanced three-phase nonlinear loads is conducted. A novel fuzzy instantaneous power (FIP) theory is proposed to improve conventional p-q theory dynamic performances during transient conditions to adapt automatically to any random and rapid nonlinear load change. Adding fuzzy rules in p-q theory improves the decomposition of the alternating current components of active and reactive power signals and develops correct reference during rapid and random current variation. Modifying p-q theory internal high-pass filter performance using fuzzy rules without any drawback is a prospect. In the simulated system using MATLAB/SIMULINK, the shunt active filter is connected to a rapidly time-varying nonlinear load. The harmonic detection parts of the shunt active filter are developed for FIP theory-based and p-q theory-based algorithms. The harmonic detector hardware is also developed using the TMS320F28335 digital signal processor and connected to a laboratory nonlinear load. The software is developed for FIP theory-based and p-q theory-based algorithms. The simulation and experimental tests results verify the ability of the new technique in harmonic detection of rapid changing nonlinear loads.

• 한국직업건강간호학회지
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• 제9권1호
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• pp.39-48
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• 2000

Hyperlipemia is the most leading risk factor of cardiovascular disease which is the main cause of death in Korea. However, there is a tendency to neglect the prevention and treatment since it has no specific symptoms. It has been reported that the level of serum-lipid can be lowered by the improvement of eating habits. Therefore, it is highly likely that the development of programs on the improvement of eating habits through behavioral theory is required to the community nursing practice. The theory of planned behavior, which assumes that human behaviors are determined by one's intention to carry out the behavior, can be characterized by the point that behaviors are not only individual factors but also social behaviors relating to subjective norms. It is widely recognized that this theory has a high predictability on health behavior due to it's simplicity clearness, and measurability as well as high quality of being general. Thus, the theory of planned behavior could be useful in developing a model of a health promotion program to the change of behaviors of the risk group of cardiovascular disease. Consequently, based on the theory of planned behavior, the purpose of this study is to develop an intention promotion program of the diet, and then to testify the effects. The sample of this study consisted of 26 industrial workers who had proved hyperlipemia from a medical examination in 1996 (experimental group 13, control group 13). The intention promotion program, which includes education, monitoring, pressure, counselling on the level of individuals, families and organizations, was conducted for 10 weeks The purpose of this program was to promoting intention of the diet through changes of the prerequisite factors of intention such as behavioral belief, outcome evaluation, normative belief and control belief. When it came to data analysis, the ${\chi}^2$-test and Fisher's Exact test were used to compare the general characteristics between the experimental and the control group, an independent t-test for the other variables. ANOVA was used to the test hypothesis, and the Pearson correlation test for variable's correlation. The results of this study can be summarized as follows ; 1) There was a significant increase in the intention(F=18.51, p=.00) of diet in the experimental group. 2) Diets(F=32.51, p=.001) in the experimental group were better carried out than in the control group. 5) There was a moderate correlation between the intention of diet and performance (r=.587. p=.003). From the results, it can be concluded that the intention promotion program is very effective, leading to the change of health promotion behavior. Above all, it is really valuable that the intention promotion program in this study regards health promotion behavior as a social behavior and that intervention was done on the level of family and organization. Consequently, when performing a health promotion program, social approach elevating the intention should go hand in hand in order to make the program effective.

• 지식경영연구
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• 제21권2호
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• pp.77-100
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• 2020

This study conducted a qualitative study on 23 seniors over 55 years old to understand the digital behavior of seniors in the online education acceptance environment. Grounded Theory methodology was applied to the initial enrollment behavior, login behavior, and utilization behavior of online education program. Through the process of open coding, axis coding, and selective coding, the framework in the online education environment of the senior generation was finally derived. As a causal conditions for the senior generation to participate in the online education environment, goal orientation, relationship orientation, leisure orientation and external compulsory were derived, and shadow work appeared as the central phenomenon. Also, contextual conditions resulted in social change, physical and cognitive aging, and psychological atrophy. The intervening conditions included digital device acceptance, educational attitudes, environmental factors, and self-efficacy. Based on this, the action/interactions strategy formed a positive and negative attitude toward shadow work. As a result, positive response behavior, compromising behavior, and shadow work avoidance behavior were shown. It is hoped that this study will be reflected in future researches for the use of digital devices of the elderly and the expansion of online education participation and government policy.

• 한국IT서비스학회지
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• 제22권3호
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• pp.1-27
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• 2023

The semiconductor industry is a competitive, complicated and a cyclical sector with a highly dynamic business climate which requires an effective leadership style to operate and succeed. This study explores the important issue of how leadership facilitates employee innovative work behaviors in the semiconductor industry. Based on the assumptions of the ambidextrous leadership theory and social exchange theory, we collected data from 300 workers employed in the semiconductor industry of South Korea. The study investigated (1) the impact of ambidextrous leadership on innovative work behavior, (2) the mediating effects of workers decision-making autonomy and workplace learning in the relationship between ambidextrous leadership and innovative work behavior, (3) the moderating role of resistance to change in the relationship between ambidextrous leadership and workplace learning, and (4) the moderating role of openness to experience in the relationship between ambidextrous leadership and innovative work behavior. SmartPLS 4 and SPSS v24 was used to analyze our data. The study revealed that ambidextrous leadership positively influences workers innovative work behavior. In addition, decision-making autonomy and workplace learning partially mediated the relationship between ambidextrous leadership and innovative work behavior. Moreover, resistance to change was found to be a significant moderator in the relationship between ambidextrous leadership and workplace learning. Based on these findings, we conclude that ambidextrous leadership is very imperative for semiconductor businesses seeking to foster employee innovative work behaviors. Theoretical and practical implications of the study are also discussed.

• 한국정보시스템학회지:정보시스템연구
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• 제25권3호
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• pp.1-30
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• 2016

Purpose The purpose of this study is to grasp the factors influencing domestic SNS users' privacy protection behavior and verify their relationship through self-efficacy and responsiveness. Thus, this study tries to suggest efficient and effective measures for SNS personal information protection. Design/methodology/approach To this end, with main variables of the protection motivation theory based on the assumption that when users are exposed to the threat to their health, they would have protection motivation and change their behavior of protecting their health, a research model was suggested. In addition, in order to empirically verify the research model, a survey was performed targeting general college students having the experience of using SNS. Findings As a result of the analysis, first, perceived effectiveness and self-efficacy had a positive effect on responsiveness. Second, perceived barrier had a positive effect on self-efficacy. Third, self-efficacy and responsiveness had a positive effect on privacy protection behavior. This study is expected to contribute to establishing an effective guideline for measures that could induce SNS users' privacy protection behavior.