• 한국초등과학교육학회지:초등과학교육
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• 제33권4호
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• pp.700-709
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• 2014

The purpose of this study was to examine the effects of question-generating strategy on science academic achievement, scientific attitude in elementary science class. To examine the effects of question-generating strategy this learning materials were applied to elementary science curriculum, and an experimental group and a control group were selected from $5^{th}$ graders at H elementary school located in Gyeonggi-do. Students were taught for 6 weeks. Control group take traditional lessons and solve questions presented textbook. Question generated group generate questions, solve them and feed back by themselves. The results of this study were found statistically significant difference in the pupil's enhancement of the science academic achievement, scientific attitude (p<.05). Thus question-generating strategy for elementary science inquiry instruction that has a positive effect on interests in class is useful and better be widely applied to science education.

• 산업경영시스템학회지
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• 제37권4호
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• pp.202-211
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• 2014

Pairs trading is a type of arbitrage investment strategy that buys an underpriced security and simultaneously sells an overpriced security. Since the 1980s, investors have recognized pairs trading as a promising arbitrage strategy that pursues absolute returns rather than relative profits. Thus, individual and institutional traders, as well as hedge fund traders in the financial markets, have an interest in developing a pairs trading strategy. This study proposes pairs trading rules (PTRs) created from a price ratio between securities (i.e., stock index futures) using rough set analysis. The price ratio involves calculating the closing price of one security and dividing it by the closing price of another security and generating Buy or Sell signals according to whether the ratio is increasing or decreasing. In this empirical study, we generate PTRs through rough set analysis applied to various technical indicators derived from the price ratio between KOSPI 200 and S&P 500 index futures. The proposed trading rules for pairs trading indicate high profits in the futures market.

• 한국자동차공학회논문집
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• 제21권4호
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• pp.83-88
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• 2013

Recently, PCCI (premixed charge compression ignition) combustion is studied to reduce both NOx and PM because of homogeneous mixture formation and lower combustion temperature. It has also merit of increasing thermal efficiency owing to better air-fuel mixure. However, it is well known that PCCI combustion has a weakness in fuel economy because PCCI combustion tends to start before TDC. Therefore, it is necessary to find an optimal conditions for PCCI combustion which maintains reduction of NOx, PM and increase of thermal efficiency. In this study, pPCCI combustion was realized by adding early injection strategy to a conventional diesel engine. In addition, the characteristics of pPCCI combustion was analized by comparing conventional diesel injection strategy. The results show that NOx and PM per power in pPCCI combution were reduced compared to a conventional diesel combustion.

• Biotechnology and Bioprocess Engineering:BBE
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• 제10권6호
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• pp.603-606
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• 2005

Ralstonia eutropha NCIMB 11599 and ATCC 17699 were grown, and their productions of poly(3-hydroxybutyrate-co-4-hydroxybutyrate) [P(3HB-co-4HB)] compared. In flask cultures of R. eutropha NCIMB 11599, cell concentration, P(3HB-co-4HB) concentration and polymer content decreased considerably with increases in the ${\gamma}-butyrolactone$ concentration, and the 4HB fraction was also very low (maximum 1.74 mol%). In fed-batch cultures of R. eutropha NCIMB 11599, glucose and ${\gamma}-butyrolactone$ were fed as the carbon sources, under a phosphate limitation strategy. When glucose was fed as the sole carbon source, with its concentration controlled using an on-line glucose analyzer, 86% of the P(3HB) homopolymer was obtained from 201g/L of cells. In a two-stage fed-batch culture, where the cell concentration was increased to 104g/L, with glucose fed in the first step and constant feeding of ${\gamma}-butyrolactone$, at 6g/h, in the second, final cell concentration at 67h was 106g/L, with a polymer content of 82%, while the 4HB fraction was only 0.7mol%. When the same feeding strategy was applied to the fedbatch culture of R. eutropha ATCC 17699, where the cell concentration was increased to 42 g/L, by feeding fructose in the first step and ${\gamma}-butyrolactone$ (1.5g/h) in the second, the final cell concentration, polymer content and 4HB fraction at 74h were 51g/L, 35% and 32 mol%, respectively. In summary, R. eutropha ATCC 17699 was better than R. eutropha NCIMB 11599 in terms of P(3HB-co-4HB) production with various 4HB fractions.

• 전기학회논문지P
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• 제67권4호
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• pp.208-213
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• 2018

In this paper, we studied the control strategy of applying STATCOM(static synchronous compensator) to mitigate the FIDVR(fault induced delayed voltage recovery) phenomenon. The proportion of motor loads is gradually increasing which might affect power system stability. Excessive reactive power consumption by the stall of the motor loads causes FIDVR phenomenon. In addition, the low inertia of the small HVAC(heating, ventilation and air conditioner) unit will not separate itself in the event of a contingency, causing system instability. For this reason, we have developed a control strategy that utilizes STATCOM efficiently through static and dynamic analysis. Case studies on a Korean power system have validated the performance of the proposed scheme under severe contingency scenarios. The results have verified that the proposed strategy can effectively mitigate FIDVR and improve the stability and reliability of the system.

• 문화기술의 융합
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• 제7권4호
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• pp.27-34
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• 2021

본 연구는 중년여성의 성공적 노화와 SOC 전략이 삶의 질에 미치는 영향을 파악하기 위한 서술적 조사연구이다. 연구대상자는 전국의 40~65세의 중년여성으로 구조화된 설문지를 이용하여 자료를 수집하였다. 수집된 자료는 SPSS WIN/PC 24.0통계프로그램을 이용해 서술적 통계, Independent t-test, one-way ANOVA, Pearson's correlation, stepwise multiple regression으로 분석하였다. 연구결과 중년여성의 성공적인 노화, SOC 대체전략과 삶의 질은 정적인 상관관계가 있었으며, 삶의 질에 미치는 요인으로 성공적 노화(β=.41, p<.001), SCO 대처전략(β=.17, p=.047) 순으로 통계적 유의성이 확인되었다. 두 변수에 의한 설명력은 24.7%였다. 따라서 중년여성의 삶의 질을 향상시키기 위해서는 성공적 노화와 SCO 대처전략을 증진시키는 프로그램의 개발과 적용이 필요하다.

• 분석과학
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• 제8권4호
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• pp.1075-1078
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• 1995

This paper describes how industry has responded to the environmental challenge. Benefits include compliance with environmental legislation; genuine reductions to environmental impact; sustainable improvements to profitability in the face of increased competitive pressure. National and international Standards for environmental management offer security and direction for a company wishing to improve environmental performance and coupled with a waste minimisation strategy many financial and environmental benefits can be achieved. Introduction of new technical skills, techniques and worker understanding to aid motivation is an essential component of such a strategy. Monitoring and targeting has a key role to play in the establishment of improved environmental performance.

• 한국임상보건과학회지
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• 제8권2호
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• pp.1450-1461
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• 2020

Purpose: The purpose of this study was to understand the degree of nursing professional intuition, major satisfaction, clinical practice satisfaction, self-leadership, and career preparation behavior of nursing college students, and to identify factors that influence career preparation behavior. Method: This study was a descriptive research study to analyze the factors affecting career preparation behavior. The data collection period was from August 03 to 30, 2020 for 4 weeks. The survey conducted an online survey of 220 students in grades 3-4 who were enrolled in 6 nursing departments located in P metropolitan city and G province, and have clinical practice experience. The collected data were analyzed using SPSS Win 20.0 program. Results: Career preparation behavior had a significant positive correlation with nursing professional intuition(r=.455, p<.001) and self-leadership(r=.539, p<.001), and major satisfaction(r=-.337, p<.001) and clinical practice satisfaction(r=-.380, p<.001) had a significant negative correlation. Self-leadership(β=.424, p<.001) was the most significant factor influencing the study subjects' career preparation behavior, nursing professional intuition(β=.170, p=.010), clinical practice Satisfaction(β=.127, p=.047), employment information(β=.122, p=.023), major satisfaction(β=.137, p=.042) in the order, these variables were found in the order of The explanatory power of the factors affecting the subject's career preparation behavior was 40.2%. Conclusion: Therefore, in order to help nursing students' career preparation behavior, a strategy to provide a variety of employment information and a strategy for nursing intervention that can improve self-leadership, clinical practice satisfaction, and major satisfaction is required.

• 적정기술학회지
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• 제5권2호
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• pp.97-105
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• 2019

전 세계 대부분의 BoP (Base of the Pyramid) 층은 균형 잡힌 식생활을 취할 수 있는 경제력을 가지고 있지 않다. 따라서 이에 대한 해결책으로 일상적으로 섭취하는 식품에 필수 영양소를 첨가하는 방법이 이들 계층에게 지출에 대한 부담을 주지 않고 영양 상태를 개선할 수 있는 방안으로 제시되고 있다. 본 연구의 목적은 적정한 신기술을 활용하여 저소득층의 영양개선에 참여한 다국적기업인 아지노모토(Ajinomoto)와 그라민다농(Grameen Danone)의 사례를 소개하고, 이들 기업의 비즈니스 전략을 비교·평가하는 것이다. 기술 중심의 적정기술이 가지는 한계점을 극복하기 위해서는 기술과 사회, 비즈니스를 아우르는 사회기술시스템으로 진화할 필요가 있다. 이를 위해 본 연구는 적정한 신기술과 저소득층(BoP) 비즈니스를 접목하여 저소득층의 삶의 질 개선과 소득 증대에 기여한 사례를 발굴하였다. 본 연구에서는 기술적 관점에서 "적정기술 2.0" 프레임워크를 통해 사례를 분석한 후, 비즈니스 모델 분석 기준을 바탕으로 BoP 비즈니스의 전략을 살펴보았다. 이러한 분석 결과를 바탕으로 4A모델을 통해 BoP 시장에서 적정기술의 성공요인을 분석하였다.

• 동양고전연구
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• 제73호
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• pp.249-279
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• 2018

본 논문은 손자병법의 '전략'을 분석하고, 이를 현대사회, 특히 기업경영에 접목하는 시도를 통해 손자병법의 현대적 응용가치를 검증하기 위한 것이다. 군대는 전쟁에서 피해와 희생을 최소화하고 빠른 시간 내에 승리를 얻기 위해 '전쟁전략'을, 기업은 최소비용으로 최대이윤을 내기 위해 '경영전략'을 사용한다. 손자병법의 '세(勢)', '응변력(應變力)', '궤도(詭道)'로 구성되는 전략의 3요소는 현대 기업경영에서의 '내부자원 분석', '외부환경 분석', '정보관리'와 연결된다. 전략의 수립단계에서 손자병법에서는 '선지(先知)', '묘산(廟算)', '군쟁(軍爭)'을 포함하는 '선승전략(先勝戰略)'의 중요성을 강조하였는데, 이는 현대 기업경영에서 '선지'는 3C분석 중 경쟁자분(competitor)과 벤치마킹으로, '묘산'은 SWOT분석과 4P's분석으로, '군쟁'은 포지셔닝전략과 시장선점전략으로 표현되고 있다. 전략의 실행단계에서 '기습전략(奇襲戰略)', '허실전략(虛實戰略)', '분합전략(分合戰略)'은 현대 기업경영에서 '기습전략'은 차별화전략과 집중화전략으로, '허실전략'은 정보관리와 합리적 포지셔닝으로, '분합전략'은 다각화전략, 집중화전략, 변화관리, 본원적 경쟁전략, 시너지효과 등으로 발현되고, 전략의 결실은 손자병법에서는 '전쟁의 승리', 현대 기업경영에서는 '경쟁우위'와 '이윤극대화'로 나타난다. 이처럼 손자병법의 전략은 표현과 방식에 있어서 약간의 차이가 있을 뿐 현대 기업의 경영전략과 궁극적으로 서로 상통하고 있어, 기원전 500년경에 쓴 병법서이지만 빠르게 변화하는 환경과 치열한 경쟁 속에 놓여 있는 현대의 기업들과 현대인들에게 경쟁의 원리와 승리의 비법을 깨닫는데 필요한 '큰 지혜'를 제공하고 있다는 것을 알 수 있다.