• KSII Transactions on Internet and Information Systems (TIIS)
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• 제12권1호
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• pp.21-40
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• 2018

In this paper, we propose the distributed robust beamforming design scheme in cognitive two-way amplify-and-forward (AF) relay networks with imperfect channel state information (CSI). Assuming the CSI errors follow a complex Gaussian distribution, the objective of this paper is to design the robust beamformer which minimizes the total transmit power of the collaborative relays. This design will guarantee the outage probability of signal-to-interference-plus-noise ratio (SINR) beyond a target level at each secondary user (SU), and satisfies the outage probability of interference generated on the primary user (PU) above the predetermined maximum tolerable interference power. Due to the multiple CSI uncertainties in the two-way transmission, the probabilistic constrained optimization problem is intractable and difficult to obtain a closed-form solution. To deal with this, we reformulate the problem to the standard form through a series of matrix transformations. We then accomplish the problem by using the probabilistic approach based on two sorts of Bernstein-type inequalities and the worst-case approach based on S-Procedure. The simulation results indicate that the robust beamforming designs based on the probabilistic method and the worst-case method are both robust to the CSI errors. Meanwhile, the probabilistic method can provide higher feasibility rate and consumes less power.

• 정보교육학회논문지
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• 제12권1호
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• pp.89-97
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• 2008

제 7차 초등학교 과학과 교육과정에서는 특히 탐구학습을 강조하고 있다. 그러나 단위 시간과 학습자료의 부족이라는 현실적인 이유 때문에 학교 교육 현장에서는 실제적인 적용이 어렵다. 본 연구에서는 이러한 문제점을 해결하기 위하여 웹기반 발견학습 시스템을 설계 구현하고 그 효과성을 검증하는데 목적이 있다. 검증 과정으로 초등학교 4학년 과학과의 용수철 늘이기 단원을 대상으로 일반적인 발견학습 모형을 적용한 비교집단과 웹기반 발견학습 시스템으로 수업을 받은 실험집단의 학업성취도에 있어 유의미한 차이가 있는지 조사하였다. 적용 결과, 웹기반 발견학습 시스템으로 수업을 한 경우, 전통적인 발견학습 모형 그대로 적용한 경우보다 학업 성취도가 높았다.

• 한국산학기술학회논문지
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• 제18권12호
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• pp.735-743
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• 2017

본 논문은 통합설계교육 방법론에 대한 연구로서 1990년대 물질조직화의 개념으로 작업하였던 건축가들 중 특히 FOA에 집중하여 건축관과 설계방법론을 고찰하고 이를 적용한 수업사례를 중심으로 통합설계교육 방법론으로서의 가능성을 고찰하는 것을 목적으로 한다. FOA의 설계방법론은 프로토타입에서 출발하여 건물을 구성하는 요소를 물질로서 다루고 다이어그램의 위상학적 변환의 과정으로 이들을 조정하고 통합하여 하나의 건물로 일관성 있게 조직화하는 방법이다. 이를 실제 본인이 지도하였던 통합설계스튜디오의 설계방법론으로 적용하여 학생들의 설계과제를 진행하고 이를 분석하였다. 통합설계스튜디오는 대지의 문화적, 역사적 맥락의 이해를 바탕으로 한 설계개념의 추출에서 시작하여, 기본법규사항과 무장애 설계에 대한 이해와 적용을 거쳐, 필요한 기술적 요소들을 적용하고 조정하면서 상세설계까지 발전시키는 것을 교육목표로 삼아 진행되었으며, 학생들은 물질조직화의 방법으로 여러 관련 이론과목에서 배운 지식들을 통합한 설계안을 도출하고자 하였다. 이 과정에서 학생들은 구조, 대지의 역사, 극장 시야각 등을 주요 물질 요소로 삼아 형태를 형성하며 학습한 지식과 설계안을 일관성 있게 통합할 수 있음을 보여주었으며, 이에 FOA의 물질조직화를 기반으로 한 설계방법론은 통합설계방법론으로서의 의의를 갖는다고 판단된다.

• 디지털융복합연구
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• 제12권2호
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• pp.475-482
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• 2014

A wide variety of contents are now provided along with the development of information appliances. The purpose of this study was to examine what should be considered to boost the quality of mobile device based e-learning contents. For this study, 12 evaluation domains and 26 evaluation items were selected using the Delphi method. The factors to be considered for mobile device based e-learning contents quality are summarized 4 factor. In other words, for the purpose of managing the quality of mobile device based e-learning contents, there exist four areas to be considered, 'foundation', 'contents', 'teaching design' and 'technology.' The findings of this study are expected to contribute to the improvement of the quality of the educational contents.

• International Journal of Advanced Culture Technology
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• 제8권2호
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• pp.176-183
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• 2020

This study inquired about the convergence learning program for childhood based on Erikson's play theory and design education for children's behavior development. I analyzed the convergence learning programs of Summer Camps in the Pacific Science Center, Galileo Learning. The contents of the programs show the most used imaginary and symbolic contents that represent the real-world problems which are related design thinking process. The curriculums and structure of the programs are based on the design thinking method and K-12 theory. The visual thinking method and the applications are used for expressing their creativity and approaching the technical skills easily. The play concept theory is an affirmative way to strengthen the children's psychological and social development. Therefore, the convergence learning program should integrate the design thinking process and apply the play concept theory for supporting and developing the children's behavior.

• 공학교육연구
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• 제12권1호
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• pp.17-23
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• 2009

본 논문에서는 컴퓨터네트워크 실습 교과목을 대상으로 한 전문대학 학습자에 적합한 PBL 교수 학습 모형의 설계 및 구현을 다룬다. 설계된 교수학습 모형은 대덕대학 2학년 학생들을 대상으로 진행하였다. PBL 수업에 참여한 학생들은 PBL 학습을 통해 문제 체계적으로 진행된 수업에 대한 만족을 나타냈으며 과제 해결을 위해 자료와 도구를 적절히 이용하는 능력을 향상시켰으며 협동학습을 통해 더 많은 것을 배울 수 있었다. 이를 학습자의 수업평가 결과를 통해 확인하였다.

• 동서간호학연구지
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• 제22권1호
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• pp.60-67
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• 2016

Purpose: This study was conducted to develop and apply simulation-based nursing education program for post-myomectomy care in nursing students. Methods: One group pre-post design was utilized. One hundred and thirty two participants consisting of 66 nursing students 132 participants consisting of 66 nursing students team were recruited. The data were collected from March 2 to June 12, 2015. Eight hours of simulation-based education program for post-myomectomy care was operated. Forty five items of Clinical Competence Assessment Scale was developed and content validity was tested using the content validity index. Results: The total score of Clinical Competence Assessment Scale was 90 and mean score of it was 82 (SD 4.2). The item showing the lowest mean score was 'education for Foley catheter management'. Mean score of performance was 92.7%, education 90.2% and assessment 89.9% respectively. Conclusion: The findings suggest that it would be useful to use the simulation-based education program for post-myomectomy care for evaluating clinical performance in nursing students.

• Earthquakes and Structures
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• 제12권1호
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• pp.109-118
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• 2017

A novel post-tensioned self-centering (SC) concrete beam-column connection with web friction devices has been proposed for concrete moment-resisting frames. This paper presents a probabilistic performance evaluation procedure to evaluate the performance of the self-centering concrete frame with the proposed post-tensioned beam-column connections. Two performance limit states, i.e., immediate occupancy (IO) and repairable (RE) limit states, are defined based on peak and residual story drift ratios. Statistical analyses of seismic demands revealed that the dispersion of residual drifts is larger than that of peak drifts. Due to self-centering feature of post-tensioning connections, the SC frame was found to have high probabilities to be recentered under the design basis earthquake (DBE) and maximum considered earthquake (MCE) ground motions. Seismic risk analysis was performed to determine the annual (50-year) probability of exceedance for IO and RE performance limit states, and the results revealed that the design objectives of the SC frame would be met under the proposed performance-based design approach.

• 디지털융복합연구
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• 제12권12호
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• pp.507-512
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• 2014

문화가 공급하는 자와 수요자와의 감정의 공유가 있어야 가능한 것임을 감안해 보더라도 수요자가 그 코드를 제대로 읽어내지 못한다면 문화의 형성은 불가능하기 때문이다. 이에 활발한 도자공예 문화의 보급은 교육의 힘으로 가능하다 할 수 있다. 우리의 도자공예문화 역시 이러한 의미에서 교육의 중요성을 다시금 확인하고 재정비 필요하다. 시대적 지역적인 도자공예가 하나의 문화로 자리매김을 위해서는 무엇보다도 교육 및 활성화 방안이 필요하다. 이에 교육 방법이나 활성화 방안으로 공방 운영에 교육의 중요성을 토대로 도자공방 활성화 방안을 연구 제시하고자 한다.

• Earthquakes and Structures
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• 제9권1호
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• pp.93-109
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• 2015

Based on the reconnaissance of buildings in Dujiangyan City during 2008 Wenchuan earthquake, China, structural damage characteristics and the spatial distribution of structural damage are investigated, and the possible reasons for the extraordinary features are discussed with consideration of the influence of urban historical evolution and spatial variation of earthquake motions. Firstly, the urban plan and typical characteristics of structural seismic damage are briefly presented and summarized. Spatial distribution of structural damage is then comparatively analyzed by classifying all surveyed buildings in accordance with different construction age, considering the influence of seismic design code on urban buildings. Finally, the influences of evolution of seismic design code, topographic condition, local site and distance from fault rupture on spatial distribution of structural damage are comprehensively discussed. It is concluded that spatial variation of earthquake motions, resulting from topography, local site effect and fault rupture, are very important factor leading to the extraordinary spatial distribution of building damage except the evolution of seismic design codes. It is necessary that the spatial distribution of earthquake motions should be considered in seismic design of structures located in complicated topography area and near active faults.