• Journal of information and communication convergence engineering
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• 제8권4호
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• pp.387-392
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• 2010

This study focuses on improving MIMO-OFDM systems by combining a wireless communication architecture known as vertical BLAST(bell laboratories layered space-time) or V-BLAST and STTC(space time trellis coding). In this paper, the combination is done by introducing STTC in each V-BLAST layer. Moreover, this architecture uses multiple antennas that are grouped into small number of antennas which makes it less complex to decode by decoding every group. Whereas, in traditional V-BLAST, all the antennas form one group and they are decoded together at the receiver, therefore, this increases the complexity as the number of antennas is getting high. We compare the bit error rate performance of this system with MIMO-OFDM that uses convolutional coding instead of STTC. Under the same spectral efficiency, the simulation results prove that joining V-BLAST with STTC improves MIMO-OFDM systems performance.

• 반도체디스플레이기술학회지
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• 제10권2호
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• pp.1-5
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• 2011

In recent years, worldwide production of solar wafers increased rapidly. Therefore, the solar wafer technology in the developed countries already has become an industry, and related industries such as solar wafer manufacturing equipment have developed rapidly. In this paper we propose the color classification method of the polycrystalline solar wafer that needed in manufacturing equipment. The solar wafer produced in the manufacturing process does not have a uniform color. Therefore, the solar wafer panels made with insensitive color uniformity will fall off the aesthetics. Gaussian mixture models (GMM) are among the most statistically mature methods for clustering and we use the Gaussian mixture models for the classification of the polycrystalline solar wafers. In addition, we compare the performance of the color feature vector from various color space for color classification. Experimental results show that the feature vector from YCbCr color space has the most efficient performance and the correct classification rate is 97.4%.

• 한국도서관정보학회지
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• 제52권4호
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• pp.103-126
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• 2021

본 연구는 충청남도교육청 소속 19개 공공도서관을 대상으로 교육·문화복합공간으로서의 도서관 재구조화 방안을 제안하고자 하였다. 이를 위해 국내외 공공기관 복합화 시설의 사례 조사, 이용자 설문조사 등을 실시하였다. 그 결과 미래 공공도서관이 갖추어야 할 공간으로 배우는 공간(종합자료실, 테마 자료 탐구실, 미래교실, 블렌디드 러닝센터, STEAM 교육실, 원격강의학습실), 표현하는 공간(포이어, 메이커 룸, 디지털 매체 창작실, 원격강의제작실), 나누는 공간(동아리·모둠학습실, 웰빙 복합문화공간, 생활·편의공간, 휴게실·브라우징), 즐기는 공간(퍼포먼스·생각 놀이터, 유아·어린이 자료실, 디지털 가상체험실, 특화 알코브실, 야외독서실) 등으로 구분하여 공간 재구조화 전략을 제시하였다. 또한, 건축 규모, 장서 규모, 서비스 및 공간 수준 등을 고려하여 선도모형, 기본모형, 이음터 모형, 최소모형 등 도서관별로 특화된 교육청 소속 공공도서관의 재구조화 모형을 제안하였다.

• 천문학회보
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• 제45권1호
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• pp.40.4-40.4
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• 2020

Kyung Hee university invented the Transformable Reflective Telescope (TRT) for optical experiment and education. The TRT kit can transform into three optical configurations from Newtonian to Cassegrain to Gregorian by exchanging the secondary mirror. We designed the Ebert-Fastie spectrograph as an extension of the TRT kit. The primary mirror of the TRT kit serves as both collimator and camera lens, and the reflective grating as the dispersing element is placed along the optical axis of the primary mirror. We designed and fabricated the grating holder and the source units using 3D printer. Baffle was also fabricated to suppress the stray light, which was reduced by 83%. The spectrograph can observe the optical wavelength range (4000Å~7000Å). Measured resolving power (R=λ/Δλ) was ~700 with slit width of 0.18mm. The spectrograph is optimized for f/24, and the spectral pixel scale is 0.49Å/pixel with Canon 550D detector. We present the sample spectra of discharged Ne, Ar and Kr gases. The flexible setting and high performance make this spectrograph a useful tool for education and experiment.

• 한국실내디자인학회논문집
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• 제15권2호
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• pp.99-107
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• 2006

People with visual impairments are difficult to go to education facility by themselves, because of their limited visual ability, orientation, and usability field, so they prefer dormitories. Those dormitories playa role in living space, education, communication and culture function. Therefore those facilities planned more user centered design, since they are influenced by user actability and their values. User centered designs that match between the user and space are understood as well as their characteristics and behavior. Especially for understanding their activity, observation is conducted about their behavior in dormitories. Thus the purpose of this study is suggested to be a basic source that planning about residential facility for people with visual impairments through interview and observation investigation by analysis that they resident in space motion and performance.

• Steel and Composite Structures
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• 제30권4호
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• pp.315-325
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• 2019

Double skin composite walls offer structural and economic merits over conventional reinforced concrete counterparts in terms of higher capacity, greater stiffness, and better ductility. This paper investigated the axial behavior of double skin composite walls with steel truss connectors. Full-scaled tests were conducted on three specimens with different height-to-thickness ratios. Test results were evaluated in terms of failure mode, load-axial displacement response, buckling loading, axial stiffness, ductility, strength index, load-lateral deflection, and strain distribution. The test data were compared with AISC 360 and Eurocode 4 and it was found that both codes provided conservative predictions on the safe side.

• 정보교육학회논문지
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• 제12권1호
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• pp.41-48
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• 2008

현재 과학과 수행평가는 교사평가가 주를 이루고 있기 때문에 평가 결과의 피드백이 신속하게 이루어지지 못하고, 시 공간적 제약으로 인하여 동료평가가 거의 이루어지지 않는다. 또한 과학과 수행평가에서 주로 시행되는 보고서 수행평가의 경우 체계적인 형식 없이 실험관찰에 기록된 내용으로 평가되는 경우가 많다. 이러한 수행평가 방법은 수행 기준의 공유를 통한 성취의욕 향상, 평가결과의 즉각적인 피드백을 통한 자기조정이라는 수행평가의 기대에 부응하지 못할 수밖에 없다. 따라서 본 연구에서는 웹을 기반으로 동료학습자 간의 자료공유와 토의를 통해서 실험 및 조사 보고서를 완성하고 이를 동료평가, 교사평가에 활용하며 그 결과를 통해 학습자의 요구 수준을 파악하고 학습자에게 적절한 피드백을 제공하는 수행평가 시스템을 개발하였다.

• 교육시설
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• 제12권5호
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• pp.25-34
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• 2005

The Educational Cultural Center for Students is a new mixed-cultural space which made around 1997 for students' education of humanism and talent with the 7th revision of educational course. This Educational Cultural Center for Students is different to the existing one because the subject of the culture is students who make creation and performance by themselves while the former ones were for seeing, hearing and feeling things. There are seven Educational Cultural Center for Students all over the country and will be built more in the future. Comparing to the former Educational Cultural Centers for Students, functional rooms in the Educational Cultural Centers for Students are an outdoor performance room, a large performance room, a small performance room of performance facility, a gallery of display facility, a gymnasium, a swimming pool, a fitness room, a table-tennis room of physical facility, a library and a reading room of a book facility, and a group room, a computer room, a singing room, a billiard room, an art room, a musical room, a dancing room, a manner room, a playing room, a cultural lecture room and a seminar room of a interest-activity facility. The result of analyzing the usage frequency is that a performance room has the highest frequency and a display room, a musical room, a music appreciation room and a physical room follow the frequency order. But this frequency does not fit for all area. By place and social situations, the frequency and space organization may be changed.

• 벤처창업연구
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• 제13권1호
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• pp.31-41
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• 2018

본 논문은 정부의 창업지원사업이 외형적 예산투입관점에서는 크게 증가함에도 불구하고 창업기업들의 현장에서 필요로 하는 니즈에 맞게 적절하게 이루어지지 못한다는 문제에 대해, 창업지원사업을 수혜 받은 기업들을 대상으로 정부지원 세부사업에 대한 중요도와 만족도를 조사하고 이의 차이인 기대충족도를 분석하여 그 원인을 분석하고 개선방안을 제시하는데 목적이 있다. 이를 위해, 본 연구는 충청남북도에 소재한 창업기업들을 대상으로 창업가가 인식한 정부의 창업지원사업 만족도가 경영성과에 미치는 영향을 살펴보았다. 특히 본 논문은 창업지원사업 중 어떠한 정부지원이 경영성과에 가장 큰 유의미한 영향을 미치는지를 분석하였다. 연구결과는 다음과 같다. 첫째, 창업지원사업의 창업교육, 시설 공간, 컨설팅, 자금지원 각각 분야의 중요도와 만족도의 차이에 대한 통계적 유의성을 검정한 결과 모든 분야에서 유의미한 차이가 있는 것으로 나타났다. 또한 중요도와 만족도의 차이가 가장 큰 분야는 자금지원으로 나타났다. 둘째, 창업지원사업과 재무적 성과와의 영향관계를 분석한 결과 시설 공간 만족도가 재무적 성과에 정(+)의 영향을 미쳐 시설 공간 만족도가 높을수록 재무적 성과가 높아지는 것을 알 수 있다. 창업지원사업과 비재무적 성과와의 영향관계를 분석한 결과 창업교육 및 컨설팅 만족도가 비재무적 성과에 정(+)의 영향을 미쳐 창업교육 및 컨설팅 만족도가 높을수록 비재무적 성과가 높아지는 것을 알 수 있다. 마지막으로 본 논문은 기대충족도가 가장 낮은 자금지원사업에 대해 그 수치가 가장 높은 창업교육 및 컨설팅사업과 연계하여 맞춤형 지원사업을 개발하는 것을 정책대안으로 제시하였다.

• 한국수학교육학회지시리즈D:수학교육연구
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• 제9권1호
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• pp.25-45
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• 2005

Background Phenomenography suggests that more variation is associated with wider ways of experiencing phenomena. In the discipline of mathematics, broadening the 'lived space' of mathematics learning might enhance students' ability to solve mathematics problems Aims The aim of the present study is to: 1. enhance secondary school students' capabilities for dealing with mathematical problems; and 2. examine if students' conception of mathematics can thereby be broadened. Sample 410 Secondary 1 students from ten schools participated in the study and the reference group consisted of 275 Secondary 1 students. Methods The students were provided with non-routine problems in their normal mathematics classes for one academic year. Their attitudes toward mathematics, their conceptions of mathematics, and their problem-solving performance were measured both at the beginning and at the end of the year. Results and conclusions Hierarchical regression analyses revealed that the problem-solving performance of students receiving non-routine problems improved more than that of other students, but the effect depended on the level of use of the non-routine problems and the academic standards of the students. Thus, use of non-routine mathematical problems that appropriately fits students' ability levels can induce changes in their lived space of mathematics learning and broaden their conceptions of mathematics and of mathematics learning.