• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 1999년도 추계학술대회 논문집 - 한국공작기계학회
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• pp.470-475
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• 1999

Recently as the application of gear drive increases in high-speed and high-loading, the concern of designing multi-stage gear drive is being risen. Until now however, the research of gear drive is focused on single-stage gear drive and the design depends on experiences and know-how of designer and is carried out by trial and error. This research automated the basic design and the configuration design for two and three-stage gear drives which consist of cylindrical gears. In basic design, design is executed with two design processes, which minimize the overall volume of gear, and whose results are compared each other. In configuration design, the positions of gears are determined to minimize the volume of gearbox using the result of basic design and simulated annealing algorithm.

• 한국초등과학교육학회지:초등과학교육
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• 제33권4호
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• pp.634-645
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• 2014

The purpose of this study was to analyze the teachers' stages of concern and levels of use on STEAM of the 2009 elementary science curriculum and to support effective application according to the teachers' stages and levels. Therefore this study was conducted by the Concerns-Based Adoption Model (CBAM). The total number of 113 teachers participated in this study. The results of the study were as follows: First, most teachers were in the stage of awareness. Second, the results of the chi-square test showed that the stages were significantly different according to their positions, training experiences and final degrees (p<.05). Third, about half of teachers were in the level of orientation and preparation. The others were in the level of routine, integration and renewal. Fourth, the results of the chi-square test showed that the levels were significantly different with the categories of their gender, position, age, career in education, workplace and training experience (p<.05). Fifth, the correlation coefficient between stages of concern and levels of use (r=.59) was relatively high (p<.05). Based on these results, we suggested that the support of application should be provided according to the teachers' stages and levels.

• 과학교육연구지
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• 제39권1호
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• pp.99-112
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• 2015

이 연구의 목적은 초등 교사가 융합인재교육(STEAM)에 어떤 관심을 가지고 있는지 그리고 융합인재교육 시범학교를 운영하면서 융합인재교육에 대한 관심도가 어떻게 변화하는지를 알아봄으로써 새롭게 적용되는 융합인재교육에 대한 기초 자료를 제공하는데 있다. 이 연구에서는 Hall에 의해 개발된 관심도 검사 도구(SoCQ)를 사용하였다. 연구대상은 융합인재교육 시범학교를 운영하고 있는 초등학교 90명이며, 시범학교 운영 기간인 4월, 6월, 12월에 관심도의 변화를 조사하였다. 이 연구를 통해 밝혀진 결과를 요약하면 다음과 같다. 첫째, 융합인재교육 시범학교를 운영하고 있는 전체 초등교사의 관심도의 변화는 4월에는 무관심 단계가 가장 높고 결과적 관심이 가장 낮았으나 12월에는 무관심과 운영적 관심이 낮아졌다. 4월과 비교하여 결과적 관심의 평균값이 54.7에서 74.3로 가장 크게 증가하였다. 교사들의 개인적인 변인을 대상으로 탐색한 결과는 다음과 같다. 고등학교 이과를 이수한 초등 교사들은 운영적 관심의 단계가 낮게 나타났으며, 석사 이상의 학력을 갖춘 초등 교사의 경우도 운영적 관심의 단계가 낮게 나타났다. 아울러, 교육대학교 STEM 관련 교과의 심화과정을 졸업한 초등 교사들 역시 운영적 관심의 단계가 낮게 나타났다. 개인의 요인에 따라 융합인재교육을 받아들이는 관심 단계가 차이가 있음을 알 수 있다. 탐색적 연구의 결과는 융합인재교육의 통합적 접근을 위해 가치 있는 기초 자료를 제공할 것이다.

• 한국초등과학교육학회지:초등과학교육
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• 제21권2호
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• pp.227-239
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• 2002

The purpose of this study was to improve the practice of performance assessment in elementary science education and to support it according to the levels teachers' concerns. So this study was conducted by applying CBAM which is based on teachers' concern, which was designed for the investigation of the elementary science teachers' concern, their performance level, intellectual understanding, status of performance. and stage oi awareness and the connections between these factors. The study involved 311 elementary school teachers in the city of Seoul. The result of this study was as follows: First, the stage of teachers’ concerns performance assessment in science marked 49.5％, indicating that about half of the teachers was staying on the informative stage which could be generally occurring in the beginning of performance the curriculum innovation. The level of performance marked 33.8%, which was regarded as the stage of elaboration. For the category of intellectual understanding, most of the teachers didn’t fully understood the performance assessment. Regarding the status performance, 90.4％ of the teachers were implementing the assessment at the state of knowing the purpose of it. However. 40.5% of the teachers didn't fully understand the specific characteristics of the assessment. Also, the results of analyzing the teachers’ awareness on science performance assessment indicated that they have slightly positive positions. Secondly, the result of analyzing the stages of concerns for the assessment, based on the elementary school teachers' personal background, levels of implementation, and their intellectual understanding showed that the concerns were significantly different with the categories of their workplaces(p<.05). Finally, the result of analyzing the relationship among the concerns for the science performance assessment, levels of implementation and intellectual understanding indicated that there were significant differences in levels of implementation with the degree of intellectual understanding (p<.001).

• International Journal of Internet, Broadcasting and Communication
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• 제16권2호
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• pp.103-111
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• 2024

We address the problematic issue of blinking in residential LED lighting systems-a phenomenon that has recently become a significant concern due to voltage sags caused by high-power household appliances. To combat this, we developed a two-stage LED converter with integrated anti-blinking circuitry, specifically designed for T5 LED indirect lighting fixtures. The first stage employs a Power Factor Correction (PFC) boost circuit to enhance voltage stability by aligning the voltage and current phases, thereby minimizing power losses. The second stage, a meticulously engineered DC-DC buck converter, ensures stable lighting despite electrical fluctuations. Rigorous testing has confirmed our converter's efficacy in maintaining consistent light output without blinking, thereby substantially improving user comfort and adhering to strict standards for harmonic distortion and electromagnetic compatibility. Our breakthrough provides a robust solution to a pressing issue, marking a significant advancement in LED lighting technology.

• 한국콘텐츠학회논문지
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• 제20권8호
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• pp.75-87
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• 2020

본 연구에서는 초등교사의 SW교육에 대한 관심도 및 실행수준을 관심중심수용모형(Concerns-Based Adoption Model)을 통해 분석하여 SW교육의 지속적인 현장 적용을 위한 교사교육에서의 시사점을 도출하고자 하였다. 이를 위해 현직 초등학교 교사 152명을 대상으로 설문을 실시하였고, 수집된 데이터를 분석하였다. 연구 결과, 초등교사의 SW교육에 대한 관심도는 0단계(지각)부터 2단계(개인) 측면의 관심이 높은 초기 관심 단계를 보이고 있었다. 현재 SW교육을 실행하고 있는 교사는 현장에서 SW교육을 단기적으로 시행하는 것에 집중하는 기계적 실행과 일상화 수준에 있는 것으로 나타났으며, 실행하고 있지 않은 교사의 과반수는 SW교육을 실행하기 위한 의도가 없는 것으로 나타났다. 교사의 성별, 교직경력, SW연수경험, SW교수경험에 따라 교사의 SW교육 관심단계에 유의미한 차이가 나타났으며, 담당학년, SW연수경험, SW교수경험에 따라 SW교육 실행수준에 유의미한 차이가 있었다. 이러한 결과를 바탕으로 현직 초등학교 교사들의 SW교육 관심 변화를 촉진하기 위한 방안을 교사를 대상으로 한 다양한 SW교육 제공 및 교수경험 확대의 측면에서 제안하였다.

• 한국인구학
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• 제18권2호
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• pp.51-69
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• 1995

이 연구는 한국사회에서 사회복지 정책을 어떻게 전개해 나가야 할 것인지에 관한 관심 속에서 선진복지국가인 스웨덴의 사회복지제도가 어떻게 발전해 나갔는지를 인구변천에 초점을 맞추어 살펴보고 있다. 먼저 스웨덴과 한국의 인구발전과정을 인구변천모형에 따라 분석하고, 인구변천 단계에 따라 사회복지가 어떻게 발전해 나왔는지를 주로 사회복지 법규를 통해 규명하고 있다. 다음 각 단계별 법규와 사회보장비 지출을 검토하여 스웨덴의 복지발달과정의 이념을 규명한 후, 한국의 사회복지정책이 어떤 방향을 나가야 할지를 제시하고 있다. 연구결과 스웨덴에 비해 한국의 사회보장비지출은 절대 부족상태이며, 스웨덴이 보편주의적 서비스를 강조하는데 비해 한국은 특수집단에 대한 서비스를 강조하고 있음이 부각되었다. 또 한국은 특수한 역사적, 문화적 요인에 의해 보훈계통의 비용이 지불되고 있다. 이 연구의 정책적 함의는 한국사회도 앞으로 소극적인 복지정책보다는 스웨덴에서 처럼 보편주의, 생산주의 및 가정복지를 바탕으로 한 복지민주주의 정책에 대한 적극적인 자세가 필요함을 제시하고 있다.

• 대한가정학회지
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• 제34권4호
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• pp.327-343
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• 1996

The objective of this study were 1) to determine the stages of concern of HE teachers about the practical problem-based curriculum approach, as illustrated by the Ohio's Work and Family Life Curriculum (W&FLC); 2) to determine the relationships between home economics (HE) teacher's stages of concern about W&FLC and personal and professional characteristics of HE teachers; and 3) to determine aspects of interest about the practical problem-based curriculum approach, such as the Ohio W&FLC. Respondents in this study were 225 HE teachers. The data were collected during the in-service teacher training sessions after presentation about W&FLC. Concerns Based Adoption Model (CBAM) was modified to provide a conceptual framework for this study. Frequencies, SD, mean, mode, range were used to determine the stages of concern of HE teachers. To determine the relationships between stages of concerns and personal and professional characteristics of HE teachers, coefficient of Chi-Square contingency tables was used. Content analysis was used to determine aspects of interest about the practical problem-bsed curriculum approach, such as W&FLC. The median of the stages of HE teachers' concerns about W&FLC was Stage 1, Information Stage. About 60% of HE teachers were interested in learning more details about W&FLC. Chi-square revealed no statistically significant relationships between stages of concerns about W&FLC and characteristics of HE teachers. Content analysis was used to determine aspects of interest about W&FLC of HE teachers. Nine categories were found: content, teaching strategies, implementation of the curriculum, philosophical framework, how to adopt W&FLC, resource materials, students' outcomes, in-service teacher training, and HE teacher organization. The majority of HE teachers were interested in relationships with family and others, resource management, family relationships, personal development, communication skill, family life, creating a self-identity, life planning, roles of family members, homemaking management, child care, and parenting.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2008년도 동계학술발표대회 논문집
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• pp.119-124
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• 2008

Recently, focus has been drawn on natural refrigerants due to increasing concern on global warming. As a consequence, CO2 systems such as a heat pump water heater using CO2 as a refrigerant are rapidly growing on the market. Currently, rolling piston rotary compressors are widely used for CO2 heating and/or refrigeration systems. There are several ways of realizing gas compression structure. They are single stage compression with single cylinder, single stage compression with two cylinders, and two stage compression with two cylinders. In this paper, computer simulation program which was validated for a single stage rotary compressor with one cylinder has been extended for a single stage, two cylinder rotary type. Numerical investigation has been made on optimal design for the cylinder configuration using the extended simulation program. For a single stage two cylinder rotary compressor having a displacement volume of 4 cc for each cylinder, compressor efficiency has been found to be maximum when the cylinder radius and height are 31mm and 10mm, respectively.

• 영재교육연구
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• 제24권6호
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• pp.917-934
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• 2014

이 연구는 관심중심수용모형(Concern-Based Adoption Model)을 통해서 영재교육 담당교원 직무연수 연수대상 교사들의 영재교육에 대한 단계별 관심도와 연수 후 관심도 변화 수준 차이를 분석하기 위하여 수행되었다. 연구의 목적을 달성하기 위하여 B광역시 영재교육진흥원에서 주관한 2014학년도 초 중등 영재교육 담당교원 직무연수에 참여하였던 연수 교원 162명 중에서 설문에 성실하게 응답해준 102명을 대상으로 교사들의 변인별(성별, 학교 급별, 과목별) 영재교육에 대한 관심도와 연수 전과 후의 관심도 차이를 분석하였다. 이 연구를 통해 영재교육 담당교원 기초과정 직무연수는 영재교사를 양성하고 영재교육에 대한 저변확대를 위해서 반드시 필요한 연수이며, 연수대상 교사들에게 영재교육에 대한 자신감을 향상 시켜주고 관심도에 대한 필요를 충족시켜주고 있음을 확인할 수 있었다.