• Journal of Power Electronics
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• 제9권6호
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• pp.949-959
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• 2009

This paper presents a systematic investigation of the fault-mode behaviors of matrix converter systems. Knowledge about converter behaviors after fault occurrence is important from the standpoint of reliable system design, protection and fault-tolerant control. Converter behaviors have been, in detail, examined with both qualitative and quantitative approaches for key fault types, such as switch open-circuited faults and switch short-circuited faults. Investigating the fault-mode behaviors of matrix converters reveals that converter operation with switch short-circuited faults leads to overvoltage stresses as well as overcurrent stresses on other healthy switching components. On the other hand, switch open-circuited faults only result in overvoltage to other switching components. This study can be used to predict fault-mode converter behaviors and determine additional stresses on remaining power circuit components under fault-mode operations.

• 한국생활과학회지
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• 제16권5호
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• pp.899-908
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• 2007

Clusters of parental and peer variables associated with adolescent risk behaviors are explored using the mixture model. Questionnaires were completed by 917 high school freshmen in the Daegu Kyungpook area and included measures of risk behaviors, parental attachment, autonomy, parental monitoring, and peers' risk behaviors and desirable behaviors. As a result of the mixture model, five clusters were produced. Two of the subgroups were consistent with the literature of showing linear relationships among adolescent risk behaviors and above variables; a group of higher parental attachment and autonomy as well as parental monitoring, lower friends' risk behaviors, and lower adolescent risk behaviors, and a group of lower parental attachment and autonomy as well as parental monitoring, higher friends' risk behaviors, and higher adolescent risk behaviors. Two other subgroups were similar in parental attachment and autonomy, but differed in parental monitoring, friends' risk behaviors, and adolescent risk behaviors. The last subgroup was characterized by scoring the lowest parental attachment and autonomy, parental monitoring, friends' risk behaviors, and lower adolescent risk behaviors compared to other subgroups. The utility of the mixture model in research on adolescent risk behaviors is discussed in the conclusion.

• Asian-Australasian Journal of Animal Sciences
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• 제23권4호
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• pp.537-542
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• 2010

The goal of this study was to investigate how spectrographic features of ultrasonic vocalizations (USVs) in rats vary among individuals and behaviors. Eighteen pairs of rats were allocated to individual pair cages. Each pair's behaviors and vocalizations were recorded during the 900s a known cage-mate was returning to the cage. The effects of individuals, behaviors, and the interaction between individuals and behaviors ($individuals{\times}behaviors$) were tested on the duration and peak frequencies. There was difference in the duration and peak frequency: i) among individuals (p<0.0001 and p<0.0001, respectively); ii) among behaviors (p = 0.0667 and p<0.0001, respectively); iii) among individuals${\times}$behaviors (p<0.0001 and p<0.0001, respectively). The frequency of ultrasonic vocalizations changed with a frequency ranging from 40 to 71 kHz which were emitted by individuals, whereas the frequency of ultrasonic vocalizations changed with a frequency ranging from 60 to 70 kHz which were emitted by behaviors. The peak frequency of call on 'contact' behavior was lower than that of call on other behaviors, but call duration of call on 'contact' was longer than on other behaviors. Especially, 40 kHz calls were found on 'contact' and 'other' behaviors. We suggest that ultrasonic vocalizations need to be subdivided and the effects of individuals and behaviors must be considered to assess emotional state of rats because these may influence the features of ultrasonic vocalizations.

• 한국방사선학회논문지
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• 제16권5호
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• pp.611-618
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• 2022

본 연구는 COVID-19 상황 속에서 온라인 수업을 경험한 방사선(학)과 대학생들을 대상으로 수업 중 이루어지는 딴짓의 정도를 확인하고 자기주도적 학습역량, 몰입과 학업성취도가 딴짓에 미치는 영향을 규명하기 위함이었다. 연구방법은 서술적 조사연구이며, 연구 대상은 방사선(학)과 학생들로 구조화된 설문지를 이용하여 2022년 6월 1일부터 6월 30일까지 조사하여 200부를 최종 분석 대상으로 하였다. 수집된 자료는 SPSS/WIN 21.0을 이용하여 척도의 신뢰도를 검증하고, 딴짓을 유형을 파악하고 한 후 일반적 특성, 딴짓, 자기주도적 학습역량, 몰입과 학업성취도에 대하여 기술통계, 분산분석, Pearson's 상관관계 그리고 다중회귀분석을 실시하였다. 연구결과 대상자들의 딴짓은 '딴 생각하기', '문자하기' 순이 였으며 딴짓은 1.75점, 자기주도적 학습능력은 3.60점, 몰입은 3.23점, 학업성취도는 4.29점으로 나타났다. 딴짓과 자기주도적 학습역량, 몰입과 학업성취도 간에는 유의한 음의 상관관계가 있었으며, 딴짓에 미치는 영향을 미치는 요인은 학업성취도, 나이, 몰입, 자기주도적 학습능력 순이었다. 이상의 결과로 방사선(학)과 대학생들의 딴짓을 낮출 수 있는 방법이 학업성취도를 높이는 것임으로 수업에 몰입할 수 있는 구체적 방안 및 다양한 교수법이 필요할 것으로 기대된다.

• International Journal of Fuzzy Logic and Intelligent Systems
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• 제4권3호
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• pp.327-336
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• 2004

In distributed autonomous mobile robot system, each robot (predator or prey) must behave by itself according to its states and environments, and if necessary, must cooperate with other robots in order to carry out a given task. Therefore it is essential that each robot have both learning and evolution ability to adapt to dynamic environment. This paper proposes a pursuing system utilizing the artificial life concept where virtual robots emulate social behaviors of animals and insects and realize their group behaviors. Each robot contains sensors to perceive other robots in several directions and decides its behavior based on the information obtained by the sensors. In this paper, a neural network is used for behavior decision controller. The input of the neural network is decided by the existence of other robots and the distance to the other robots. The output determines the directions in which the robot moves. The connection weight values of this neural network are encoded as genes, and the fitness individuals are determined using a genetic algorithm. Here, the fitness values imply how much group behaviors fit adequately to the goal and can express group behaviors. The validity of the system is verified through simulation. Besides, in this paper, we could have observed the robots' emergent behaviors during simulation.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2003년도 컴퓨터소사이어티 추계학술대회논문집
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• pp.137-140
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• 2003

This paper proposes a pursuing system utilizing the learning method where multiple cooperating agents emulate social behaviors of animals and insects and realize their group behaviors. Each agent contains sensors to perceive other agents in several directions and decides its behavior based on the information obtained by the sensors. In this paper, a neural network is used fir behavior decision controller. The input of the neural network is decided by the existence of other agents and the distance to the other agents. The output determines the directions in which the agent moves. The connection weight values of this neural network are encoded as genes, and the fitness individuals are determined using a genetic algorithm. Here, the fitness values imply how much group behaviors fit adequately to the goal and can express group behaviors. The validity of the system is verified through simulation.

• 가정과삶의질연구
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• 제19권5호
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• pp.221-238
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• 2001

The purpose of this study was to investigate the relationships between parental childreating behaviors and parental personality, and children’s emotional intelligence. The subjects included 223 children from kindergarten to 6th grade and their parents. The results were as follows: Firstly, children’s Emotional Intelligence(EI) showed sex difference and age difference between two grade-groups(kindergarten~3rd grade, 4th~6th grade). the age-differences being more distinct in other-related EI than in the self-related : Secondly, parental personality explained parental childrearing behaviors better in higher-grade groups than in lower-grade groups, maternal personality predicting maternal childreating behaviors better than paternal personality predicting the paternal childreaing behaviors; Thirdly, childrearing behaviors explained childern’s self-relate EI better than the other-related : Finally, parental personality revealed greater predictive power of children’s EI in higher-grade groups than in lower-grade groups, better explaining sel-related EI than the other-related. Several suggestions were made concerning future EI studies.

• 보건교육건강증진학회지
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• 제23권3호
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• pp.99-119
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• 2006

Objectives: This study intends to understand the difference within group of social support level and the effect of social support to health behaviors and health status of the elderly by selecting the old of local society as target. Methods: Data were obtained from self-administered questionnaire of 8,688 persons, older than 65 years, living in a community. We measured the sociodemographic characteristics, social support(family support, other support, quality of support), physical health state(subjective health status, number of chronic disease), physical function state(activities of daily living; ADL, instrumental activities of daily living; IADL), cognition state(mini-mental state examination-Korean; MMSE-K) and depression state(short form of geriatric depression scale; SGDS), health behaviors(smoking, drinking, exercise, eating habit). Univariate, multinominal logistic regression and covariance structure analysis were employed to analyze factors affecting on the social support of the elderly. Results: When considering the degree of social support by the sociodemographic characteristics of the older adults, the family support, other support and quality of support is better when the old is male, young, high education and self-reported living status is good and it has significance statistically. When considering the relation between social support and health status, the family support, other support and quality of support is better when the old's subjective and objective physical health status is good. The family support, other support and quality of support is better when the old's subjective health status is better. The other support and quality of support is better when the old's ADL(activities of daily living) and IADL(instrumental activities of daily living) are good. The family support, other support and quality of support is better when the old's cognitive function and depression state is better. When considering the relation between social support and health behaviors, in case of smoking and drinking, the quality of support, family support and other support is better when the old smokes and drinks rather than the old does not. In case of exercise and eating habit, the family support, other support and quality of support is better when the old exercises and eats regularly rather than the old does not. It has significance statistically. From the result of performing covariance structure analysis by structural equation modeling(SEM) with two endogenous variable(health behaviors and health status) and one exogenous variable(social support), factor loading of health status is 0.74 and factor loading of health behaviors is 0.05. The social support explains health status of 55.4% and health behaviors of 2.9%. Conclusions: This study has the meaning that it finds the difference of social support generating from inside of the group for the old residing in city and country and specifies the effect that the difference of social support influences to health status and health behaviors. From now on, in the development of health improvement strategy of the olds, it is necessary to approach from inclusive aspect while considering psychosocial factor such as social support and social economical factor as well as health status.

• 대한가정학회지
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• 제41권1호
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• pp.111-124
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• 2003

This study tries to analyse the relationship between sexual attitudes and behaviors on the one hand and parent-child relationships on the other among college students in Korea. 1,237 students from different areas were surveyed. Sexual attitudes are subdivided into four aspects, namely, permissiveness, instrumentality, emotional exchange, and responsibility, and sexual behaviors into indirect and direct ones. Results are as follow. First, sexual attitudes and behaviors among the subjects are found being different, depending on such variables as sex, religion and dating experiences. Secondly, while being related with both indirect and direct sexual behaviors, the variable of co-residence with parents is significantly related with the aspect of permissiveness, but not with the other three aspects. Thirdly, the parent-child communication is significantly related with sexual attitudes. One who has an open pattern of communication with parents tends to have more desirable sexual attitudes and is better able to control sexual behaviors.

• 한국의상디자인학회지
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• 제24권3호
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• pp.33-48
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• 2022

This study aimed to investigate bag purchase behaviors according to materialism value. The subjects were 443 male and female adult consumers in their 20s to 50s. The research method was a survey, and the questionnaire consisted of questions on materialism value, bag purchase behaviors, and demographic characteristics. For data analysis, descriptive statistics, Cronbach's α, χ² test, factor analysis, cluster analysis, ANOVA, and Duncan's multiple range test were performed. The results of this study were as follows. First, materialism value was derived from three factors (happiness pursuit, possession-oriented, and success judgment). Second, subjects could be divided into three groups (happiness pursuit group, success judgment pursuit group, and immaterialism group) based on the materialism value variable. Third, the derived groups showed many differences in bag purchase behaviors. The happiness pursuit group considered all bag evaluation criteria factors (practicality, aesthetics, economy, symbolism) and bag purchasing information sources factors (mass media and personal sources) more than other groups, and showed a tendency to prefer select shops and complex shopping malls as bag purchasing places. In addition, the average annual cost and frequency of purchasing bags of this group were higher than those of other groups. The success judgment pursuit group considered symbolism as a bag evaluation criteria more than other groups, and considered personal sources as bag purchasing information sources more than mass media sources, and preferred luxury stores and department stores as bag purchasing places. On the other hand, the immaterialism group considered practicality and aesthetics as bag evaluation criteria and placed less importance on all information sources than other groups, and preferred Internet shopping malls as purchasing places. This group had the lowest average annual purchase cost and frequency among the three consumer groups. This study suggested that materialism value is a useful variable to segment male and female adult consumer markets effectively, and to understand the bag purchase behaviors of consumer groups divided by materialism value.