• Proceedings of the KIPE Conference
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• 2017.07a
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• pp.413-414
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• 2017

영구자석 동기전동기 구동 인버터 시스템 내 스위치 고장은 다양한 조합으로 발생한다. 특히 스위치 개방고장의 경우 다른 전기 부품에 과전류를 유발하여 전체 시스템에 심각한 2차 손상을 초래한다. 본 논문에서는 개방고장 진단 알고리즘의 복잡성을 완화하기 위해 고장 그룹을 분류하여 고장 발생 시 false alarm의 영향을 받지 않고 간단하고 체계적인 방식으로 고장을 식별할 수 있는 기법을 제안한다. 스위치의 개방 고장으로 영구자석 동기전동기 구동 시스템 내 PWM 전압원 인버터의 신뢰성을 향상시키기 위해 3중 스위치 개방고장 진단 및 검출 기법을 제시한다. 제안된 기법은 기존의 개방고장 진단방법과 달리 정보처리를 위해 Moving Filter를 사용함으로써 연산부하를 증가시키지 않고 신속한 고장 검출이 가능하며 별도의 하드웨어 구성없이 구현이 가능하다. 제안된 기법의 안정성과 유효성이 시뮬레이션을 통해 입증된다.

• Journal of Digital Convergence
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• v.15 no.11
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• pp.433-440
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• 2017

The present study explored the impact of personality and self-identity on online information acquisition, information transmission and the usage of SNSs. Participants were 180 students, SNS users, from a university in Korea. Among the participants, 171 students completed all surveys. As a results, personality traits such as openness, extraversion, agreeableness, neuroticism were positively related to the SNS usage and information behaviors. Social identity orientation was associated with time spent of SNS and the number of friends whereas collective identity orientation was related to information acquisition. As a result of multiple regression, time spent, openness, agreeableness, collective identity were significant predictors of information acquisition. The number of SNS in use, time spent of SNS, openness, neuroticism were predictors of information transmission. However, as the predictor of information transmission, neuroticism showed inverse relationship with information transmission.

• School Mathematics
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• v.18 no.1
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• pp.193-214
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• 2016

Teachers' questioning plays an important role in mathematics teaching and learning by asking students to react or to participate in mathematical discourse. Previous studies on teachers' questioning have not focused on how to questioning to formulate an effective mathematical discourse which is contributed by students because studies mostly analyzed and categorized teachers' questions according to cognitive levels of questions without consideration of context. Therefore, this study explored characteristics of teachers' questioning to formulate an effective characteristics of teachers' questioning to formulate an effective mathematical discourse in mathematics classrooms. By reviewing and analyzing mathematics discourse and studies on teachers' questioning theoretically, we presented openness, sharedness, and productivity as characteristics of teachers' questioning. Through a middle school mathematics teacher's case, we examined three characteristics were necessary to formulate an effective mathematical discourse. Based on results from theoretical analysis and case analysis, we discussed that openness, sharedness, and productivity would be useful as a framework to analyze teachers' questioning.

• The Journal of the Korea Contents Association
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• v.22 no.2
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• pp.559-577
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• 2022

The purpose of this study was to analyze the influence of Big 5 Personality Traits(Extroversion, Agreeableness, Conscientiousness, Openness to experience, Neuroticism) on the organizational commitment of employees and also to investigate the moderating effect of leadership. To summarize the research results, First, Extroversion, Agreeableness, Conscientiousness, Openness of Big 5 Personality Traits had a positive effect on organizational commitment. Second, transactional, transformational and servant leadership had a moderating effect on the relationship between conscientiousness and organizational commitment. And transactional and transformational leadership had a moderating effect on the relationship between openness and organizational commitment. In Pharmaceutical and Medical Device Companies, it was confirmed that personality traits of employees are important factors that affect organizational commitment and organizational leadership interacts with the personality of employees and affects organizational commitment. This study is meaningful in that it attempted to analyze the moderating effect through quantitative design using the scale for the role of personality factors and leadership individually.

• 프린팅코리아
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• v.9 no.11
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• pp.78-79
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• 2010

• Journal of Intelligence and Information Systems
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• v.15 no.2
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• pp.15-31
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• 2009

The next generation IT environment is expected to be an open computing environment based on Grid computing technologies, which allow users to access to any type of computing resources through networks. The open computing environment has benefits in aspects of resource utilization, collaboration, flexibility and cost reduction. Due to the variation in performance of open computing resources, however, resource allocation simply based on users' budget and time constraints often fails to meet the Service Level Agreement(SLA). This paper proposes the Mean-Absolute Deviation(MAD) portfolio optimization approach, in which service brokers consider the uncertainty of performance of resources, and compose resource portfolios that minimize the uncertainty. In order to investigate the effect of this approach, we simulate an open computing environment with varying uncertainty levels, users' constraints, and brokers' optimization strategies. The simulation result concludes threefolds. First, the MAD portfolio optimization improves the success ratio of delivering the required performance to users. Second, the success ratio depends on the accuracy in predicting the variability of performance. Thirdly, the measured variability can also help service brokers expand their service to cost-critical users by discounting the access cost of open computing resources.

• Journal of Labour Economics
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• v.29 no.1
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• pp.1-39
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• 2006

This paper documents the increase in earnings variability (or earnings risk) during the 1990s in Korea, and investigates whether it can be accounted for by capital market opening. The variances of transitory and permanent innovations in earnings are estimated from repeated cross-section data using a simple econometric framework. The increasing time-series pattern of earnings risk among men follows the increased foreign capital presence reasonably well, but the supporting cross-sectional evidence for a causal relationship between the two is weak. However, foreign direct investment (FDI) is found to have had some non-neutral effects on workers of varying skills in such a way that transitory earnings risk of less-skilled workers relatively increased with FDI. To the extent that transitory innovations are not fully insured, this widening effect of FDI on earnings risk gap may have contributed to widening welfare gap between skilled and unskilled workers in Korea, at least in terms of "risks."

• Journal of Korea Technology Innovation Society
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• v.17 no.3
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• pp.563-583
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• 2014

We classified collaboration types of Government-supported Research Institutes (GRIs) in Korea to make a creation knowledge with the openness and the diversity. The openness is described to collaboration dependence and leading intensity, and the diversity is expressed to collaboration diversity and collaboration concentration. We suggest four taxonomy models explained in terms of the openness and the diversity with country level and institute level. This study uses 39,507 papers in SCOUPS DB that include author(s) affiliated to 26 GRIs. It concludes that many GRIs is classified to the type of multilateral collaboration follower in institute level and to the type of global network player in country level from the perspective of openness. In the aspect of diversity, many GRIs is concentrated to the collaboration type of picky eater or monophagous in institute level and to the multinatioal asymmetry type or non-multinational asymmetry type in country level. It is necessary for GRIs to lead collaboration and to transfer inhouse R&D institutes with high performance to be competitive institutes which make high quality knowledge.

• Polymer(Korea)
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• v.25 no.5
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• pp.679-690
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• 2001

High resilience PU foams were prepared with polyether type cell opener. The influences of cell opener concentration on the kinetics, rheology, structural stability morphology and open cell content of the obtained foam were investigated and the role of cell opener during cell opening was determined. And mechanical properties as a function of cell opener concentration were studied. It was observed that urea formation reaction was delayed due to high hydrophilicity of cell opener The decrease of viscosity and the increase of tan $\delta$ were confirmed with increasing cell opener concentration so that the resulted foam had low structural stability and high open cell content. The deterioration of matrix and uniform dispersion of hydrogen-bonded urea in matrix with cell opener concentration was revealed by SEM analysis. As a result, elastic properties of the foam matrix were decreased due to high hydrophilicity of cell opener during the preparation of high resilience polyurethane foam and foam with high open cell content resulted. Hardness, tensile strength, tear strength, elongation of foam were decreased with increasing cell opener concentration.

• Journal of Digital Convergence
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• v.18 no.4
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• pp.75-80
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• 2020

This study verified the moderating effect of brand familiarity and openness in the relationship between micro and macro-national image in Chinese market and brand attitude. The research methods used in this study based on previous studies, a research model was established, related research hypotheses were set up, and Chinese consumers were selected as survey subjects to conduct surveys and data collection, and the suitability test and research hypothesis of the model were verified. As a result of this study, Micro and macro-national image had a positive effect on brand attitude, brand familiarity and openness had no moderating effect on micro-national image, and macro-national image had a moderating effect on macro-economic image. The results of this study provide implications for companies in Korea, the United States, and Japan, which have close relations with China in the Chinese market, to utilize various business strategies.