• Proceedings of the KIPE Conference
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• 2019.11a
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• pp.10-12
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• 2019

영구자석 동기 전동기는 높은 효율과 전력 밀도 등의 장점때문에 자동차나 엘리베이터 등 다양한 산업 분야에서 사용되고 있다. 영구자석 동기 전동기의 구동에는 여러가지 이유로 인해 고조파 토크 리플이 존재한다. 이러한 토크 리플은 속도 리플을 유발하여 소음이나 진동의 원인이 되며, 그 분포가 전동기의 구조나 운전점에 따라 변화하기 때문에 제어 성능에 매우 큰 영향을 준다. 본 연구에서는 영구자석 동기 전동기의 운전점에 따라 변화하는 토크 리플을 상쇄하기 위해 주입할 최적의 고조파 토크를 실시간으로 추적하는 방법을 제안한다. 제안된 방법에서는 속도 제어 중 토크 리플에 의해 발생하는 속도 리플을 적분하여 평가지표로 삼고, 속도 리플이 감소하는 방향으로 주입할 고조파 토크의 크기와 위상을 조정한다. 이 방법은 제정수 추출이나 회전자의 위치 별 토크 테이블 없이 운전 조건의 변화에 따라 토크 리플의 최적 보상점을 추적한다는 장점이 있다. 제안된 방법의 효과는 시뮬레이션을 통해 검증되었다.

• Proceedings of the KIPE Conference
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• 2012.07a
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• pp.582-583
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• 2012

가변자속 영구자석 동기전동기는 자속의 변화에 따라 전동기의 제정수도 변화하므로, 수학적 모델 기반의 역기전력 추정 센서리스 제어를 적용하는 경우 제정수 오차로 인해 센서리스 제어 성능이 저하된다. 본 논문에서는 3kW급 가변자속 영구자석 동기전동기에 대해서 자속 가변에 따른 전동기 제정수 변화를 살펴보고, 이를 기반으로 가변자속 영구자석 동기전동기에 적합한 센서리스 제어 알고리즘에 대해 살펴보고자 한다.

• Korean Journal of School Psychology
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• v.11 no.1
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• pp.253-274
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• 2014

The present study classified groups based on latent profile of self-determination motivation(amotivation, external motivation, intrinsic motivation), and examined the determinants for each group. The data was collected through panel data of Korea Education Longitudinal Study(KELS), total 5,459 participants who answered questionnaires of self-determination motivation of two times both second grade of middle school and second grade of high school. To identify the change motivational type, standardized residual was conducted using SPSS 17.0., and the latent classes for the change of motivational type was investigated using M-Plus in the frame work of Latent Profile Analysis(LPA). The results indicated that five groups(increase of self-determination, self-determination maintenance, self-determination developmental delay, elf-determination confusion, decrease of self-determination group) were classified based on latent profile. In addition, parental control, academic self-concept, teacher-student relationship, test anxiety, avoidance orientation, gender, father's education, and income were significantly related to each group. Lastly, the implications for directions of the adolescent counseling, limitations and future research are discussed.

• The Korean Journal of Coaching Psychology
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• v.7 no.1
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• pp.59-89
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• 2023

In this study, change motivation for growth and development is defined as 'the power to set a specific action direction for change based on the perception of one's current behavior in order to achieve a goal that one considers important, and to be willing to act'. In addition, the purpose of this study was to develop and validate a scale to measure the motivation for change for growth and development of general adults. To develop preliminary questions, interviews were conducted with 7 coaching experts and 9 experienced coaches, and an open-ended questionnaire was conducted with 55 adults. Afterwards, 7 factors and 83 questions were selected through three rounds of item classification and content validity verification, and a preliminary survey was conducted targeting 321 general adults, and 42 items, 4 factors, were derived through exploratory factor analysis. did Finally, the main survey was conducted with 631 adults in order to verify the validity of the construct concept of the change motivation scale and the validity of the criterion. Divided into two groups, 315 people in group 1 conducted exploratory factor analysis and 316 people in group 2 conducted confirmatory factor analysis to verify the concept of change motivation scale. As a result of the factor analysis of Group 1, it was found that the 3 factor structure consisting of 31 items was appropriate, and as a result of the confirmatory factor analysis of Group 2, the goodness of fit of the modified model of the 3 factor structure was confirmed, which motivated change. The construct validity of the scale was demonstrated. As a result of analyzing the correlations with various variables for the analysis of convergent validity and criterion-related validity of the Motivation for Change scale, each of the three factors was found to be significantly related to most variables. Finally, the significance, implications and limitations of this study, and future research were discussed.

• Proceedings of the KSAR Conference
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• 2004.06a
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• pp.219-219
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• 2004

Human erythropoietin (hEPO) 유전자가 도입된 형질전환돼지는 수태와 임신율을 일반돼지와 비교를 해 보았을 때 매우 낮은 경향을 보이는 것으로 나타났으며, 이러한 경향의 원인을 구명하기 위하여 인위적인 발정동기화 및 호르몬을 이용한 과배란 유기시 배란과 수정(수태)시 성호르몬 변화를 비교하고자 실시하였다. 먼저 발정동기화를 위하여 PG 600 (PMSG 400 IU, HCG 200IU)을 주사한 후 10일 후에 Regumate porcine을 6일간 급여한 후에 PMSG 주사하고 2일 후에 hCG 주사한 다음 인공수정을 실시하였다. (중략)

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.32 no.3
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• pp.316-320
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• 1996

터빈 노즐 면적을 최적화함과 동시에 동기화 시킴으로서 기관의 싸이클 특성의 변화를 시도하였다. 그 결과 동력 추출을 위한 가스 유동이 제한을 받게 되고 최종의 팽창비 $\delta$에 의하여 싸이클의 변화가 이루어졌으며 동력의 이득은 싸이클 효율이 증가됨으로써 성취되었다.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.858-859
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• 2011

고성능과 고효율 전동기인 매입형 영구자석 동기기에 사용되고 있는 희토류계 영구자석은 높은 가격과 수급 문제로 인해 최근 이슈화 되고 있다. 희토류계 영구자석을 대체하여 페라이트 영구자석을 적용할 수 있지만 낮은 잔류자속밀도로 인해 고출력을 얻을 수 없다는 문제점이 있다. 그러나 최근 높은 잔류자속밀도를 가진 고밀도화 페라이트 자석이 출시되면서 이를 적용한 매입형 영구자석 동기기의 특성을 해석할 필요성을 가지게 되었다. 본 논문에서는 고밀도화 페라이트 자석을 이용한 매입형 영구자석 동기기의 특성 해석을 하였다. 특히 영구자석의 재질 변경으로 인해 동기기의 토크와 토크 리플의 변화를 비교하고 코깅 토크에 의한 변화도 비교하였다. 또한 매입형 회전자내에 영구자석의 형상을 1층 및 3층으로 적용하여 구조에 따른 해석을 통해 특성을 비교함으로서 고밀도화 페라이트 자석의 효율적인 적용을 얻기 위한 회전자 구조를 선택하고자 한다. 또한 이를 통해 고밀도화 페라이트 자석의 적용 가능성을 예측하고자 한다.

• Informatization Policy
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• v.20 no.3
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• pp.63-85
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• 2013

Drawing on Protection Motivation Theory(PMT), this study attempts to clarify antecedents that influence the intention to protect individuals' privacy on the Internet. Protection motivation forms through individuals' cognitive appeal involving threat and efficacy. Then protection motivation causes privacy behavioral change. Protection motivation factors are established privacy trust and privacy risk, which are related to privacy attitude and belief. This proposed model is empirically analyzed by utilizing structural equation analysis(SEM). According to the result of the empirical analysis, it is founded that almost paths have statistically significant explanatory power except path from efficacy to privacy risk and path from privacy trust to privacy behavioral intention. This study shows powerful evidence of antecedent factors based on protection motivation of individuals' privacy behavioral intention in online environment.

• Journal of the Korea Convergence Society
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• v.9 no.12
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• pp.485-493
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• 2018

This study analyzed the motivational interviewing of type 2 diabetes patients in order to understand the difficulties and motivations associated with starting insulin treatment in psychosomatic insulin-resistant patients. The method used the consistent comparative analysis. The results of study were as follows: building relationships, focusing (Self-explore of problems with diabetes self-management, Recognizing the limitations of diabetes management, Concerns about complications, Imagine the future), inducing (Imagine the expected benefits and disadvantages of insulin administration, Discovering the benefits of insulin, Changes in thinking about starting insulin therapy), planning (Show specific curiosity about change, Planning change), maintaining change behavior (Keeping change confident), and evaluating. This study will contribute to understanding patients with type 2 diabetes with psychological insulin resistance. It may also provide implications for professionals helping these subjects.

• Journal of The Korean Association For Science Education
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• v.36 no.1
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• pp.125-134
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• 2016

The purpose of this study is to explore the relationship between motivational belief about learning science, self-directed learning ability and conceptual understanding of matter change with a quantitative method, assuming that motivational belief and self-directed learning ability might affect conceptual understanding. To do this, the authors investigated middle school students' motivational belief about learning science, self-directed learning ability, and conceptual understanding of matter change using measurement tools based on previous studies, and then analysed the casual relationship between three variables using PLS structural equation model. As a result, three latent variables in this study could be evaluated as appropriated in reliability and validity. And also, self-directed learning ability could affect both the motivational belief and conceptual understanding, while motivational belief could affect only self-directed learning ability but not conceptual understanding. Through this study the authors confirmed that in the context of science learning self-directed learning ability can directly affect conceptual understanding but motivational belief can affect indirectly. This study is significant in that the causal relationship between different variables in science learning could be confirmed in a quantitate manner, and also in that it can suggest PLS structural equation method as a new research methodology in science education research area.