• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 1998.10a
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• pp.4-4
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• 1998

고체 추진제의 비정상적인 연소 현상을 해석하여 연소 불안정을 예측하는 것은 추진시스템의 설계 시 매우 중요하다. 로켓의 비정상 연소 현상을 해석하기 위하여 많은 이론적 연구가 진행되어 왔다. 이론적인 해는 주로 선형 해석의 결과들로 정상 상태에서 발생하는 불안정 현상을 예측하는 데에는 적합하지만 비정상 현상을 설명하기에는 부족하다. 따라서 수치 기법을 이용한 비선형 해석이 수행되어 졌다. 기존의 비정상 연소에 관한 연구들은 일정한 물성치를 사용하고 추진제 내에서의 화학 반응과 복사 열전달 등을 무시하여 추진제의 특성을 단순화 시켜 비정상 해석을 수행하였다. 본 연구에서는 비정상 연소 현상에 대한 비선형 수치 해석을 하려한다. 실험에서 밝혀진 것과 같이 추진제의 물성치를 온도의 함수로 사용하고 응축영역으로의 복사 열전달을 고려하였다.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.11a
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• pp.477-478
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• 2003

에너지 사용의 증대에 따라 대기중으로의 질소산화물 배출양이 증가하고 있으며, 이에 따른 산성비, 광화학 스모그등 많은 피해가 나타나고 있다. 이러한 질소산화물중 고정원에서 배출되는 질소산화물은 선택적 촉매환원법에 의해 제거가 되고 있다. 선택적 촉매 환원법에 사용되고 있는 촉매는 주로 V$_2$O$_{5}$/TiO$_2$ 계열로써 300 ~ 40$0^{\circ}C$ 영역에서 최적의 반응을 보인다(H. Bosch and F. Janssen, 1988). 그러나 촉매의 내구성 증진, 재가열에 따른 에너지 절감등의 이유로 저온에서 우수한 활성을 보이는 촉매의 개발이 필요하다. (중략)

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2011.11a
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• pp.321-324
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• 2011

본 논문에서는 contourlet 변환을 이용하여 잡음을 제거하는 방법을 제안한다. 영상 센서의 발전으로 이미지의 해상도가 좋아지는 반면 잡음에 민감해진다. 그러므로 이를 전처리 단계에서 처리해주는 것이 필요하다. 잡음은 주로 자연 영상의 윤곽선에서 민감하게 반응하기 때문에 고주파대의 잡음을 최대한 정확하게 제거하는 과정이 중요하다. Contourlet 변환은 기존의 wavelet 변환의 다중 스케일과 더불어 다양한 방향 필터뱅크를 이용하여 방향 성분에 대하여 풍부한 정보를 얻을 수 있는 변환이다. 영상의 화이트 가우시안 잡음을 제거하기 위해 contourlet 변환 영역에서의 계수를 이변수 가우스 확률 모델로 설정하고 Bayes 추정법을 사용한다. Bayes 추정법에 필요한 파라미터들은 근사적으로 추정한다. 제안한 방식을 통하여 잡음이 제거된 영상에 추가적으로 Wiener filter와 cycle-spinning을 적용하여 더 높은 PSNR (peak signal-to-noise ratio)값을 얻을 수 있다. 모의실험을 통해 제안한 방식의 PSNR 값과 결과영상으로 성능이 우수함을 확인하였다.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 2002.11a
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• pp.128-131
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• 2002

향 관련 직업을 중심으로 한 연구에는 유기 화학적 냄새에 폭로된 종사자를 대상으로 그들의 작업환경 개선을 주된 목적으로 실시되어져왔으나 천연향 자극에 대한 연구는 전무한 상태이다. 본 연구에서는 화장품 관련 전문직과 화장품 판매직을 대상으로 100%의 basil oil, lavender oil, lemon oil, jasmine oil, ylang-ylang oil (KIMEX co. Ltd, Korea), skatole (TAKASAO co. Ltd, Japan)등 6종 향 자극에 대한 EEG, 주관평가에 대해 알아보았다. 그 결과, 전문직에서 선호도가 높은 향은 Fz와 F3에서, 선호도가 낮은 향은 P4에서 $\alpha$/$\beta$비가 증가하는 경향을 나타냈다. 상호 정보량에 대해서는 두 직업 모두 선호도가 낮은 향에 대한 상호 정보량이 선호도가 높은 향에 비해 더 많았다. 특히 화장품 관련 전문직에서는 전두엽의 상호 정보량이 증가하는 경향이 확인되었다. 이상에서 판매직과 비교하여 전문직은 천연향 자극이 감성효과가 아닌 외부자극에 대한 고차원적 기능을 담당하는 전두엽 영역과 관련된 지성효과로 작용함을 알 수 있었다.

• Proceedings of the Korea Information Processing Society Conference
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• 2010.04a
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• pp.566-569
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• 2010

레이저 포인터를 검출하는 과정은 포인터의 위치를 검출하는 과정과 입력된 레이저 포인터의 좌표를 모니터의 좌표로 변환하는 과정으로 나눌 수 있다. 레이저 포인터의 추적에 있어서 다변하는 환경의 영향으로 강건성의 확보가 어렵다. 기존의 추적 방식인 Mean-Shift 알고리즘의 경우에는 계산량이 많아서 실시간으로 입력되는 동영상에는 부적합하다. 반면에 CamShift 알고리즘은 빠른 수행이 가능하여 비디오 영상 및 실시간 영상에 적용하기에 적합하고 배경 변화의 영향을 적게 받는다. 또한 검출하려는 색과 같은 색에 의해서 간섭 받는 현상을 방지할 수 있다. 배경이 복잡한 형태이거나 배경이 동적으로 움직일 때에도 강건한 결과를 얻을 수 있다. 제안된 알고리즘을 실환경에 적용한 결과 검출하고자 하는 물체가 예측 영역을 넘나들거나 또는 화면으로부터 지나치게 멀어지거나 가까워져서 상대적인 크기가 변화할 수 있는 불확실한 변화에도 안정적으로 반응함을 알 수 있었다.

• Journal of Gifted/Talented Education
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• v.13 no.3
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• pp.1-17
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• 2003

Development and evaluation of distance learning for the gifted students in science and mathematics In this study, we developed and administrated the distance learning for the gifted students in science and mathematics, and analysed their responses. To do this, four types of teaching programs - lectures using program for distance learning, practice activities using simulation program, tasks solving programs based on discussions, and problem solving activities - were developed and students responses were analysed in eight area - stimulus, difficulties, structure, learning circumstances, involvement, interaction, learning outcomes, comparison with other learning -. As results, it was found that many students responded positively and thought programs helped their creativity, logical thinking, intelligent ability, and information searching ability. Students preferred practice activities based on appropriate guidances to lectures providing detailed explanations. And interaction could be stimulated by inducing discussion.

• Science of Emotion and Sensibility
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• v.12 no.1
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• pp.33-44
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• 2009

This study investigates differential impacts of the positive and negative content and the interaction with pacing, as a structural feature, on information processing while watching televised video clips with moderately intensive emotional tone. College participants watched six positive messages and six negative video clips lasting approximately 60 seconds. Heart rate was used to index attention and skin conductance was used to measure arousal. After all of the stimuli were shown, the participants performed the free recall questionnaire. The result demonstrates, first, positivity superiority on attention in which participants' heart rates were slower during positive content compared to during negative content. Secondly, negativity superiority was shown on free recall memory as participants remembered positive content better than did negative content. The result also manifests the interaction of emotional valence and pacing as the effects of pacing were less for the negatively emotional content compared to those for the positively emotional content. It is suggested that future studies should examine further about the differential and independent functions of positive and negative contents on information processing and the potential interaction with formal features.

• The Journal of the Korea Contents Association
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• v.12 no.9
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• pp.226-233
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• 2012

Purpose: The purpose of this study was to develop and analyze the effectiveness of an education program counseling manual (EPCM) for community-based visiting nurses. Methods: Seventy-eight of community-based visiting nurses was enrolled in this study. Data were collected using structured questionnaires and analyzed using descriptive statistics, the ${\chi}^2$-test, and the paired t-test in SPSS version 18.0. Results: Nurses had higher mean scores for counselor activity self-efficacy: skill self-efficacy, session management self-efficacy and counseling challenges self-efficacy, after EPCM than before EPCM. Significant differences were found after applying the EPCM. Conclusion: The results of this study indicate that the EPCM is effective at improving counselor self-efficacy of community-based visiting nurses.

• Journal of Korean Home Economics Education Association
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• v.26 no.1
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• pp.1-16
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• 2014

The purpose of this research is to develop a theme-based integrated teaching/learning plan in clothing, food, and housing in home economics and to apply the developed process in classes for evaluation in order to identify the suitability in schools. The theme-based integrated teaching/learning plan developed on the basis of textbooks consist four sub-themes; choosing($1^{st}$ and $2^{nd)$ lessons), using($3^{rd}$ lesson), processing ($4^{th}$ lesson), and alternatives($5^{th}$ and $6^{th}$ lessons) under the main theme of 'green family life'. The results from 20 individual and group activities showed that the students actively solved the problems when the presented cases were related to their own lives or experiences. The opportunity to implement green life through activities motivated students' willingness to proceed in real life. However, it is vital to assist integrated thinking through various examples before beginning due to students with difficulties connecting the issue from one area to the other during the problem-focused activity. The students' ability to solve the activity workbook had been improved as the lessons continued. From the survey questions on the theme-based integrated lessons, all items associated with integration of clothing, foods, and housing were positively responded. Also, questions regarding general understanding, suitability and satisfaction on the teaching/learning process were marked positive. The conclusion could be that the integrated theme related to clothing, food, and housing in our life would be appropriate for green family life. The theme-based integrated teaching/learning plan is effective in understanding the occurrence of green family life in relation with clothing, food, and housing, identifying the practical ideas implementing green life in those areas, and improving the integrated ability to solve the green life related problems. However, this research has its weakness in generalizing the results due to its limited survey respondents and post-evaluation being the only assessment conducted.

• Journal of Korean Home Economics Education Association
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• v.19 no.4
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• pp.91-117
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• 2007

This study was to compare the contents and practical problems addressed, the process of teaching-learning method, and evaluation method of Korean Home Economics curriculum and of the Oregon and Ohio's Practical Problem Focused Family & Consumer Sciences Curricula. The results are as follows. First, contents of Korean curriculum are organized by major sub-concepts of Home Economics academic discipline whereas curricular of both Oregon and Ohio states are organized by practical problems. Oregon uses the practical problems which integrate multi-subjects and Ohio uses ones which are good for the contents of the module by integrating concerns or interests which are lower or detailed level (related interests). Since it differentiates interest and module and used them based on the basic concept of Family and Consumer Science, Ohio's approach could be easier for Korean teachers and students to adopt. Second, the teaching-learning process in Korean home economics classroom is mostly teacher-centered which hinders students to develop higher order thinking skills. It is recommended to use student-centered learning activities. State of Oregon and Ohio's teaching-learning process brings up the ability of problem-solving by letting students clearly analyze practical problems proposed, solve problems by themselves through group discussions and various activities, and apply what they learn to other problems. Third, Korean evaluation system is heavily rely on summative evaluation such as written tests. It is highly recommended to facilitate various performance assessment tools. Since state of Oregon and Ohio both use practical problems, they evaluate students mainly based on their activity rather than written tests. The tools for evaluation include project documents, reports of learning activity, self-evaluation, evaluation of discussion activity, peer evaluation in a group for each students for their performance, assessment about module, and written tests as well.