• KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
• /
• 제2B권3호
• /
• pp.125-132
• /
• 2002

PMSMS (permanent magnet synchronous motors) are widely used in industrial applications and home appliances because of their high torque to inertia ratio, superior power density, and high efficiency. For high performance control, accurate informations about the rotor position is essential. Sensorless algorithms have lately been studied extensively due to the high cost of position sensors and their low reliability in harsh environments. A novel position sensorless speed control for PMSMs uses indirect flux estimation and is presented in this paper. Rotor position and angular velocity are estimated by the proposed indirect flux estimation. Linkage flux and magnetic field flux are calculated by the voltage equations and the measured phase current without any integration. Instead of linkage flux calculation with integral operation, indirect flux and differential magnetic field are used for the estimation of rotor position. A proper rejection technique fur current noise effect in the calculation of differential linkage flux is introduced. The proposed indirect flux detecting method is free from the integral rounding error and linkage flux drift problem, because differential linkage flux can be calculated without any integral operation. Furthermore, electrical parameters of the PMSM can be measured by the proposed TCM (time compression method) for soft starting and precise estimation of rotor position. The position estimator uses accurate electrical parameters that are obtained from the proposed TCM at starting strategy. In the operating region, a proper compensation method fur temperature effect can compensate fir the estimation error from the variation of electrical parameters. The proposed novel position sensorless speed control scheme is verified by the experimental results.

• 한국군사과학기술학회지
• /
• 제26권3호
• /
• pp.302-312
• /
• 2023

This paper describes the analysis of lightning strike zoning, the indirect lightning data simulation and the protection design for lightning indirect effects of equipment by lightning strike for unmanned aircraft consisting of composite wings. Through the analysis of lightning strike zoning according to the external shape of unmanned aerial vehicles, the structure areas that should be protected during lightning strike is derived, and the protection requirements of lightning indirect effects for flight critical equipments and equipment that must be operated upon lightning strike was derived. Lightning protection levels according to the location of mounting equipment and surrounding structure materials for each equipment was derived, and the protection design of the unmanned aerial vehicle with composite structures was also proposed from direct effect of lightning. Later, the lightning protection technology will be verified by the ground test of lightning direct and indirect effects.

• 복식
• /
• 제51권8호
• /
• pp.77-91
• /
• 2001

The purpose of this study was to investigate the effects of the perceived facial attractiveness and appropriateness of clothing on the evaluation of task performance of target person mediated by subjects'likability toward and trait evaluation of the target person. The facial attractiveness of the female university students were used as index of physical attractiveness in this study. Three levels of facial attractiveness was manipulated based on the judgements by 30 female university students. Four types of clothes were selected perceived appropriate for two assumed situations by female university students. Three female faces having high. medium, and low attractiveness were simulated with the same body dressed four types of clothing respectively using CAD system, and a total of 12 stimulus persons were created. The design for the experiment was a $3\tiems4\times2$ randomaized factorial. with three levels of facial attractiveness(high, medium, low), and four types attire(formal-masculine, formal-feminine, casual-masculine, casual-feminine), two kinds of context (job interview, dating) in which perceptions were occurred. The subjects of this study was 524 male and female(262 of male, 262 of female) university students from 3 universities in Kwangju, Korea. The data were analysed using factor analysis. descriptive statistics, regression, path analysis. The results were as follows : 1. In bogus job interview. the direct effect of perceived facial attractiveness on task performance evaluation was .175 and the indirect effect mediated by likability and trait evaluation was .285 in path analysis model. The direct effect of perceived appropriateness of clothing on task performance evaluation was .111 and the indirect effect mediated by likability only was .0564 in pass analysis model. 2. In dating situation, the direct effect of perceived facial attractiveness on task performance evaluation was .355, the indirect effect mediated by likability and trait evaluation was .188 in path analysis model. The direct effect of perceived appropriateness of clothing on task performance evaluation was .108, the indirect effect mediated by likability and trait evaluation was .060 in Pass analysis.

• 대한간호학회지
• /
• 제43권2호
• /
• pp.276-286
• /
• 2013

Purpose: This study was done to examine actor and partner effect of dementia knowledge, self-efficacy and depression on dementia preventive behavior in elderly couples. Methods: Participants were 115 couples aged 60 years or over who met eligibility criteria. All measures were self-administered. Data were analyzed using SPSS 18.0 and AMOS 18.0 program. Results: Dementia knowledge in elderly couples showed actor and partner effect on dementia preventive behavior. Self-efficacy in the wife did not have direct effects on dementia preventive behavior, but showed indirect effects through dementia knowledge. Self-efficacy in the husband showed direct effects on dementia preventive behavior and indirect effects through dementia knowledge. Wife's depression had direct actor effect on dementia preventive behavior and indirect effect through self-efficacy and dementia knowledge. Husband's depression did not have direct actor effect on dementia preventive behavior, but indirect effect through self-efficacy and dementia knowledge. Effect size of wives' dementia knowledge, self-efficacy and depression on dementia preventive behavior was larger than that of husbands'. Dementia preventive behavior, dementia knowledge and depression had a mutual effect. Conclusion: Results indicate that to promote dementia preventive activity in elderly couples, programs should be conducted for both of the couple, but focused differently for wife and husband.

• 대한간호학회지
• /
• 제48권2호
• /
• pp.154-166
• /
• 2018

Purpose: This study aimed to identify the actor and partner effects of health status, marital satisfaction, and self efficacy on retirement preparation in middle aged couples using the Actor-Partner Interdependence Model. Methods: Participants were 121 middle aged couples living in Seoul, Gyeonggi-do and Daegu City, Korea. All measures were self-administered. The collected data were analyzed using SPSS 20.0 and AMOS 20.0. Results: 1) Wife's self efficacy and marital satisfaction showed direct actor and partner effects on retirement preparation in middle aged couples. Wife's health status showed an indirect actor effect through wife's self efficacy and marital satisfaction on wife's retirement preparation, and showed an indirect partner effect through husband's self efficacy on husband's retirement preparation. 2) Husband's self efficacy and marital satisfaction showed only direct actor effect on retirement preparation. Health status among the husbands showed an indirect actor effect on husband's retirement preparation through their self efficacy and marital satisfaction, and an indirect partner effect through wife's marital satisfaction on wife's retirement preparation. 3) The actor effect size of health status on self efficacy and marital satisfaction was larger among husband's than wife's. Additionally, the partner effect size of health status on self efficacy and marital satisfaction was different between the two groups; however, the actor and partner effect size of self efficacy and marital satisfaction on retirement preparation was the same for husband and wife. Conclusion: The results of this study indicate that nursing intervention strategies for improving self efficacy and marital satisfaction are strongly needed to enhance retirement preparation of middle aged couples in Korean community.

• 한국보육지원학회지
• /
• 제14권1호
• /
• pp.167-186
• /
• 2018

Objective: The purpose of this study was to explore the structural analysis of the relationships among principals and fellow teacher's emotional support, teacher's active motivation for choosing the teaching profession, self-leadership, and child care efficacy and commitment. Methods: Data were collected from 465 child care teachers and analyzed by means of structural equational modeling(SEM). Results: First, principals and fellow teacher' emotional support was found to have a direct effect on teacher's child care commitment, as well as an indirect effect through teacher's self-leadership. Second, teacher's active motivation for choosing the teaching profession was found to have a direct effect on teacher's child care commitment, as well as an indirect effect through self-leadership and child care efficacy. Third, teacher's self-leadership was found to have a direct effect on teacher's child care commitment, as well as an indirect effect through child care efficacy. Fourth, teacher's child care efficacy was to found have a direct effect on teacher's child care commitment. Conclusion: These results suggest the need for a great deal of utility to improve teacher's child care commitment.

• 수산해양교육연구
• /
• 제28권3호
• /
• pp.701-712
• /
• 2016

The purpose of this study was to investigate the effect of democratic and autocratic behavior type of dance art instructors in elementary dance education on class satisfaction focused on mediations of flow and perceived competence. A total of 500 questionnaires were distributed but insincerely replied or double-replied questionnaires were excluded and finally 453 questionnaires were analyzed for this study. For the analysis of the data, SPSS 18.0 version was used and double mediation model operating in serial, proposed by Hayes and a bootstrapping method were used. First, instructor's democratic behavior type was statistically positive effect on class satisfaction. However autocratic behavior type was statistically negative effect. Second, the indirect effect of instructor's democratic type and autocratic behavior type on class satisfaction through the flow were statistically positive significant. Third, the indirect effect of instructor's democratic behavior type on class satisfaction through the perceived competence was statistically significant. However autocratic behavior type was statistically negative effect. Lastly, the indirect effect of instructor's democratic and autocratic behavior types on class satisfaction through the flow and perceived competence were statistically positive significant.

• 대한가정학회지
• /
• 제38권2호
• /
• pp.41-56
• /
• 2000

This study focused on the effects of family, individual characteristics of adolescents and coping behaviors on adolescent runaway. The major findings were as follows: 1. Adolescent who had higher level of family violence, lower level of communication with parent, family cohesion and adaptability, and resource adequacy perception reported higher scores in runaway. 2. Adolescents who had higher level of emotional distress, lower level of self-esteem and self-control tended to have higher scores in runaway. 3. There was a significant difference in adolescent runaway according to coping behavior styles. 4. Maladaptive coping behaviors were significantly associated with the runaway adolescent group. 5. Adaptive coping behaviors were not associated with both runaways and non-runaways group. 6. Communication with father had a direct effect on adolescent runaway and also indirect effects through emotional stress and maladaptive coping behavior. 7. Maladaptive coping behaviors had a direct effect on adolescent runaway but adaptive coping behavior had no effect. 8. Emotional stress had an indirect effect through maladaptive coping behavior on adolescent runaway. 9. Communication with father had a direct effect and an indirect effect through self-esteem of adolescents on the adaptive coping behavior. 10. Family adaptability had a direct effect on the adaptive coping behavior.

• 대한가정학회지
• /
• 제48권7호
• /
• pp.33-48
• /
• 2010

The purpose of this study was to explore the effects of family structure(parentral marital status and socioeconomic status), parental communication, academic problems, and peer relationship on juvenile delinquency. The participants were 1009 middle school and high school students in Seoul city and Gyeonggi Province. The major results were as follows: 1) Parental marital status(divorced/seperated) had both direct and indirect positive effects and lower class in socioeconomic status had an indirect positive effect on academic problems and peer relationship on juvenile delinquency rates. 2) Open maternal communication had a direct negative effect on juvenile delinquency rates. However, open paternal communication had both direct and indirect negative effects. 3) Academic problems had both direct and indirect positive effects on juvenile delinquency rates. 4) Peer relationship had a direct positive effect on juvenile delinquency rates. 5) The level of effects that each variable had differed by delinquency types. Based on these results, implications for preventing juvenile delinquency were discussed.

• 한국보육지원학회지
• /
• 제16권5호
• /
• pp.47-67
• /
• 2020

Objective: The main purpose of this study was to investigate the direct effect of maternal parenting behavior and indirect effects through preschoolers'executive function on three types of social behavior, prosocial, aggressive and withdrawn behavior. Methods: A total of 299 mothers and their preschool-aged children were the subjects of this study. Mothers completed the questionnaire that included measures of their parenting behavior, preschoolers' executive function, and social behavior. Results: First, mothers' positive parenting behavior had a direct effect on preschoolers' prosocial behavior, and mothers' negative parenting behavior had direct effects on preschoolers' aggressive and withdrawn behavior. Second, mothers' positive parenting behavior had indirect effects on preschoolers' prosocial, aggressive and withdrawn behavior through preschoolers' executive function. In contrast, indirect paths from maternal negative parenting behavior to social behavior through preschoolers' execution function were not significant. Conclusion/Implications: These findings underscore the importance of executive function during early childhood and suggest the need for effective parenting programs to promote executive function.