• Proceedings of the KIPE Conference
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• 2014.07a
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• pp.138-139
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• 2014

3레벨 NPC 인버터는 구조상 DC Link가 두 개의 커패시터로 직렬 구성되어 있어 두 커패시터 간의 전압 불균형의 문제가 발생한다. 중성점의 변동으로 인하여 스위치 소자의 소손과 제어기의 오작동 등 시스템의 안정도가 떨어지게 된다. 기존의 중성점 전압을 제어하는 오프셋 전압 인가 방식은 zero point 지점에서 불연속 스위칭 구간이 존재하기 때문에 중성점 제어가 불가능하다. 본 논문에서는 중성점 전압을 제어하기 위하여 DPWM 기법에서 중성점 전압을 제어하는 방식을 제안하였다. DC Link의 두 커패시터 전압 불균형이 발생하면 $60^{\circ}(+30^{\circ})$ DPWM 기법으로 Positive 벡터와 Negative 벡터의 스위칭 인가 시간을 조절하여 두 커패시터의 전압 균형을 이루게 한다. 시뮬레이션을 통하여 본 논문에서 제안한 방식에 대한 타당성을 검증하였다.

• Journal of Nutrition and Health
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• v.53 no.6
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• pp.629-647
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• 2020

Purpose: This study was undertaken to develop a nutrition quotient for elementary school children (NQ-C) for evaluating the overall dietary quality and eating behaviors. Methods: The NQ-C was developed by implementing 3 stages: item generation, item reduction, and validation. Candidate food behavior checklist (FBC) items of the NQ-C were derived from systematic literature reviews, expert in-depth interviews, statistical analyses of the fifth Korean National Health and Nutrition Examination Survey data, and national nutrition policies and recommendations. For the pilot survey, 260 elementary school students (128 second graders and 132 fifth graders) completed self-administered questionnaires as well as 24-hour dietary intakes, with the help of their parents and survey team staff, if required. Based on the pilot survey results, expert reviews, and priorities of national nutrition policy and recommendations, checklist items were reduced from 41 to 24. A total of 20 items for NQ-C were finally selected from results generated from 1,144 nationwide samples surveyed. Construct validity of the NQ-C was assessed using the confirmatory factor analysis, LInear Structural RELations. Results: Analyses of the exploratory factors of NQ-C identified that 5 dimensions of diet (balance, diversity, moderation, practice and environment) accounted for 46.2% of the total variance. Standardized path coefficients were used as weights of the items. The NQ-C and 5-factor scores of the subjects were calculated using the obtained weights of the FBC items. Conclusion: Our data indicates that NQ-C is a useful and suitable instrument for assessing nutrition adequacy, dietary quality, and eating behaviors of Korean elementary school children.

• The Journal of the Korea Contents Association
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• v.16 no.11
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• pp.240-252
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• 2016

The purposes of this paper examines the extant to which congruence in leader and follower rating of LMX quality is related to organizational commitment, and perceptions of organizational politics(POPs). A conceptual model is introduced that identifies four combinations of leader and follower LMX ratings of Cogliser et al.(2009): balanced/low LMX(low leader and follower LMX), balanced/high LMX(high leader and follower LMX), follower overestimation(low leader LMX/high follower LMX), follower underestimation(high leader LMX/low follower LMX). The summary of results based on a sample of 236 matched pairs of leaders and followers in KOREA is as follows: First, balanced/high LMX and follower overestimation were associated with relatively high levels of affective organizational commitment, and perceptions of organizational politics. However, follower underestimation and balanced/low LMX was related to low levels of follower outcomes. In particular, follower underestimation and balanced/low LMX were significantly different from balanced/high LMX and follower overestimation. Second, perceptions of organizational politics was negatively related to affective organizational commitment in the four LMX relationship types. Especially, the negative relationship between POPs and organizational commitment was stronger for people who are low as compared with high in LMX quality. Theoretical and practical implications of our findings as well as directions for future research are provided.

• Journal of Family Resource Management and Policy Review
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• v.25 no.4
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• pp.55-70
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• 2021

The aim of this study was to analyze the work and life balance of unmarried working cases in single-person households. Eleven cases were interviewed with a semi-structured questionnaire. The results were as follows: When they were starting as a single-person household on their own initiative and with enough preparation and planning, they expressed higher satisfaction as a single person household. For their adaptation to being a single-person household, practice education and information about household work and self-care were useful. Their thought about 'life' are focusing on self improvement and leisure activities either alone or with their friends. Their family interactions were performed with financial, emotional, and housework support from each other. Resources such as money and time were the major factors that impacted work and life balance. For work and life balance of single person househods, the cases needed political support for financial aid and flexible work arrangements.

• Journal of Nutrition and Health
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• v.56 no.3
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• pp.247-263
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• 2023

Purpose: This study was conducted to update the Nutrition Quotient for Adolescents (NQ-A), which is used to assess the overall dietary quality and food behavior among Korean adolescents. Methods: The first 30 candidate items of the measurable eating behavior checklist were obtained based on a previous NQ-A checklist, the results of the seventh Korea National Health and Nutrition Examination Survey data, Korea Youth Risk Behavior Survey data, national nutrition policies and dietary guidelines, and literature reviews. A total of 100 middle and high school students residing in Seoul and Gyeonggi Province participated in a pilot study using the 25-item checklist. Factor analysis and frequency analysis were conducted to determine if the checklist items were organized properly and whether the responses to each item were distributed adequately, respectively. As a result, 22 checklist items were selected for the nationwide survey, which was applied to 1,000 adolescent subjects with stratified sampling from 6 metropolitan cities. The construct validity of the updated NQ-A 2021 was assessed using confirmatory factor analysis. Results: Twenty checklist items were determined for the final NQ-A 2021. The items were composed of three factors: balance (8 items), moderation (9 items), and practice (3 items). The standardized path coefficients were used as the weights of items to determine the nutrition quotients. NQ-A 2021 and 3-factor scores were calculated according to the weights of questionnaire items. The weight for each of the 3 factors was determined as follows: balance, 0.15; moderation, 0.30; and practice, 0.55. Conclusion: The updated NQ-A 2021 is a useful instrument for easily and quickly evaluating the dietary qualities and eating behaviors of Korean adolescents.

• Defense and Technology
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• no.5 s.123
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• pp.58-70
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• 1989

일본은 '86년부터 중기방위력 증강계획을 착실히 추진해가고 있다. 제4차년도인 1989년의 사업계획은 내빈화 및 질높은 방위력 정비에 주안점을 두고 8개 부문으로 나뉘어 구성되었다. 이에 따라 정면에 대해 지휘통신.정보기능등 상당한 개선책을 강구할수 있게 되었다. 전체적으로 균형이 잡혀있는 것으로 보인다

• Defense and Technology
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• no.9 s.235
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• pp.44-53
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• 1998

중국은 냉전의 종식 이후 이전에 지역 내에서 미소간의 대립을 중심으로 형성되어 있었던 세력균형이 점차 다원화되고 있음에 따라, 지역 내의 강국이 되고자 하는 목표를 가지고 있기 때문에 인접국가와 분쟁에 처하게 될 가능성은 매우 커 보인다. 이러한 점에서 중국의 해군력 강화는 향후 동아시아 지역의 안보환경과 관련하여 불확실성과 불안정성을 가중시키는 중요한 요인으로 작용할 것이다. 따라서 지역 내의 군비 경쟁을 촉진시키는 요인으로 작용할 것이다.

• Journal of Korea Society of Industrial Information Systems
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• v.2 no.2
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• pp.31-39
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• 1997

퍼지로직 컨트롤러는 파라메터의 측정이 불가능하고 수학적으로 정확하게 모델링 되지 않는 제어에 효과적으로 사용되어진다. 본 논문에서는 입력값에 대해 룩업테이블을 사용하지 않고 멤버쉽 함수를 계산하여 수렴점에서의 진동을 줄이는 방법을 제안하였다. 그리고 역추균형 제어 시스템에 적용시켜 그 타당성을 확인하였다.

• Nuclear industry
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• v.26 no.11 s.285
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• pp.2-3
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• 2006

정부가 지나치게 주도하거나 혹은 산하 기관이 지나치게 주도하는 것은 모두가 바람직하지 않다. 이 양자가 긴장감을 유지하고 균형을 잡아나가는 과정이 다소 불편할 것이지만 국가적으로 이득이 된다는 것이 민주주의의 기본이다. 합력하여 일하는 체제에서 사실 누가 누구를 비판할 수는 없는 것이 정상이다. 그럼에도 불구하고 우리는 내 탓 혹은 남의 탓을 하도록 유전자가 만들어진 것 같다. 이것이 모두의 잘못이라는 점을 깨닫는 사회는 발전하고 상대방 탓만 하는 사회는 그렇지 않을 것이다.

• Electric Engineers Magazine
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• s.309
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• pp.24-28
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• 2008

이번호에서는 태양광발전시스템에 적용하고 있는 분산형 전원 배전계통 연계기술기준을 소개하기로 한다. 지금까지 국내 분산형 전원 배전계통 기술기준은 한국전력공사에서 마련한 기준을 중심으로 적용하고 있다. 참고로 이웃 일본의 경우 정부에서 정한 전기설비기술기준 해석에서 정하여 객관적이며 균형 있게 적용하면서 국가적으로 발전적인 부분을 담고 있다는 점을 강조하고 싶다.