• TTA Journal
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• s.98
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• pp.133-138
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• 2005

3GPP WCDMA 시스템은 Rel-99 표준으로부터 시작하여 보완 개선 작업을 거쳐 현재 Rel-6 표준화에 이르렀다. 이와 함께 급변하는 통신시장환경에 적절히 대처하여 향후 제정되는 3GPP 표준 시스템의 경쟁력을 향상시키고 소비자가 요구하는 다양한 서비스를 충족시킬 수 있어야 한다는 사업자들의 의견이 강하게 제기되었다. 이를 만족시킬만한 표준을 얻기 위해 각 사업자 및 제조사 등의 의견을 듣는 자리를 마련하기 위해 2004년 11월 토론토에서 3GPP Future Long-Term Evolution(LTE) Workshop을 개최하였다. 이 워크숍에서 여러 회사들로부터 물리계층에서 서비스 계층까지 다양한 의견이 제안되었으며, 특히 물리계층에서는 OFDM 기반의 기술들이 큰 주목을 받았다. OFDM 기술 자체에 대해서는 3GPP에서 새로운 것은 아니다. 이미 Rel6 표준화 작업과정에 OFDM 의 타당성 조사를 위한 작업(Feasibility Study)을 위해 OFDM Study Item(SI)가 존재하였었다[1]. 하지만 Rel6 시스템에 OFDM을 적용하려는 노력 중에 여러 사정으로 인해 표준화 실질 작업인 Work Item(WI)이 생성되지 못하고 현재 잠정적으로 중단된 상태이다. 본 기고에서는 현재 중단된 OFDM 기술 연구에 대한 과거 진행 내역 및 현재 상황, 또한 향후 RAN LTE 표준화 과정에서 강력한 대안 기술로 지목 받는 이유와 각 회사의 제안 기술들에 대해서 언급하고자 한다. 제1장은 OFDM 기술의 특징과 OFDM Study Item 과정에서 논의된 내용들에 대해서 언급한다. 제2장은 향후 표준화가 진행될 LTE에 서 물리계층 후보 기술로서의 OFDM의 위치에 대해서 논하고자 한다.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.13 no.7
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• pp.1312-1320
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• 2009

This paper presents an efficient design method of 2-D infinite impulse response(IIR) digital filter based on a particle swarm optimization(PSO) algorithm. The design task is reformulated as a constrained minimization problem and is solved by our newly developed PSO algorithm. To ensure the stability of the designed 2-D IIR digital filters, a new stability strategy is embedded in the basic PSO algorithm. The superiority of the proposed method is demonstrated by several experiments. The results show that the approximation error of the resultant filters are better than those of the digital filters which designed by recently published filter design methods. The proposed design method can also obtain the stable2-D IIR digital filters.

• Journal of The Korean Association For Science Education
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• v.35 no.3
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• pp.419-429
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• 2015

In this study, we explored students' epistemological framing during scientific argumentation and how interactions among group members influenced group argumentation. Twenty-one gifted science students divided into groups of three or four participated in this study. Students' discussions related to data interpretation concerning the rate of photosynthesis were analyzed. Students' activities were videotaped in groups so the discourse could be transcribed and students' behavioral cues analyzed. Students' epistemological framing has been identified through analysis of their speech and behavioral responses to the anomalous data from the inquiry process. Subsequently, their sources of warrant and group argumentation levels were explored. We found out that group members framed the inquiry in two ways: "understanding phenomena" and "classroom game." Group members whose framing was "understanding phenomena" required other members to justify the anomalous data by examining its validity and reliability, which conclusively demonstrated a high level of argumentation. On the other hand, when group members used "classroom game" to frame their argumentation, they did not recognize the necessity of explaining the anomalous data; rather, these students used simple empirical justification to explain the data, reflecting a low level of argumentation. When students using different epistemological framing disagreed over interpretations of anomalous data throughout the discussion, clashes ensued that resulted in emotional conflict and a lack of discussion. Students' framing shifts were observed during the discussion on which group leaders seemed to have a huge influence. This study lays the foundation for future work on establishing productive framing to prompt scientific argumentation in science classrooms.

• Journal of Engineering Education Research
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• v.1 no.1
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• pp.5-20
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• 1998

In this paper, the traditional curriculum model for engineering education, called simple hierarchical model, is critically reviewed and the problems of this curriculum model are discussed. Then a new curriculum model for engineering education is proposed to overcome the problems of simple hierarchical model and to provide an innovative education for engineering students. This new curriculum model for engineering education, called $\Pi$-structure, consists of the General Attainments Program, the Fundamental Major Program, and the Advanced Major Program, with the three components stacked in $\Pi$ shape where the first two programs are put in parallel and the third program are put on their top. The necessity, feasibility and various benefits of the $\Pi$-structured education system are widely discussed in the paper.

• School Mathematics
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• v.15 no.2
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• pp.315-335
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• 2013

Probability has distinctive characteristics which are different from other areas of school mathematics. The critical change can be noticed in the domain, 'probability and statistics' of 2009 revised national curriculum for elementary school mathematics. This indicates that the concept of chance is supposed to be taught in the 5~6 grade band instead of the definition of probability which is moved to the middle school level. The purpose of this study is to seek desirable methods for teaching the concept of chance which reflect the achievement criteria and the attention point for teaching and learning of the curriculum at the point of time when textbooks haven't yet been developed. To do this, based on theoretical considerations and comparative analysis of the curricula in the longitudinal - latitudinal dimensions respectively, the validity of the latest curriculum change was confirmed and several learning activities were devised. And then two lessons were planned for applying these activities to eight fifth graders and were implemented along the plan. As a result, the relevance of the learning activities was examined and students' difficulties in learning the concept of chance with educational implications were discussed.

• Electronics and Telecommunications Trends
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• v.2 no.4
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• pp.10-19
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• 1987

현대의 과학기술 및 정보산업 그리고 컴퓨터 관련 기술의 급속한 발전으로 인하여 슈퍼컴퓨터의 요구도가 점차 증가하고 있는 실정이다. 국내에서도 슈퍼컴퓨터의 필요성에 대하여 부분적으로 상당한 논의가 있었으며, 당 연구소에서도 슈퍼컴퓨터 도입 타당성 연구를 수행한 바 있다. 또한 최근에 한국과학기술원 부설 시스팀공학센터에서는 슈퍼컴퓨터의 기종선정 작업에 착수하여 검토중에 있다. 본 고에서는 슈퍼컴퓨터의 구조적 분류와 발전과정 그리고 벡터 처리 기법을 조사 분석함으로서 슈퍼컴퓨터의 개요 및 병렬 처리를 설명하였으며 슈퍼컴퓨터의 응용 분야 및 도입현황을 조사하였다. 그리고 슈퍼컴퓨터의 시스팀 규모를 분류함으로서 도입, 운영을 위한 각 시스팀 규모별 소요 예산을 분석 제시하였다.

• Proceedings of the Korea Technology Innovation Society Conference
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• 2017.11a
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• pp.131-131
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• 2017

그동안 지역혁신체제론의 관점에서 지역연구개발시스템의 효율성을 분석하는 다양한 연구가 수행되었다. 하지만 (1)지역연구개발시스템의 내부 처리과정 고려 미흡과 (2)연구개발의 특수성을 고려하지 못한 효율성의 분석모형 설정, (3)투입 산출지표 설정의 타당성 부족, (4)산출된 효율성 지수의 민감도 분석 소홀 등의 여러 한계점이 존재한다. 특히 5~10년 이내의 단기간으로 접근함에 따라 지역연구개발시스템의 효율성이 어떻게 변모해왔는지 그 역동성을 상세히 고찰하지 못하였다. 따라서 본 연구에서는 1999년~2014년까지 16개 광역지방자치단체를 대상으로 네트워크 자료포락분석(Network Data Envelope Analysis: DEA)의 2단계 접근법(two-stage approach)을 활용해서 지역연구개발시스템의 효율성을 분석하고 주요 개선방향들을 논의하였다.

• Journal of the Korean Data and Information Science Society
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• v.10 no.1
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• pp.199-205
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• 1999

This paper discusses the generalized mixed-effects model for the analysis of overdispersed binomial data. Sometimes certain types of sampling designs or genetic characters of experimental units can be regarded as factors of extra binomial variation. For such cases, this paper suggests models with one or two random effects to explain overdispersion caused by those affecting factors and shows how to test for a model adequacy based on deviance.

• The Journal of the Korea Contents Association
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• v.9 no.8
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• pp.309-323
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• 2009

Business simulation learning is a business education method of the software applications that applied for the university's management training. Its interest is increasing as management training tools to simulate the virtual enterprise and to learn the business management knowledge, management skills, experience and problem-solving. This research was done for the feasibility analysis and management education model design of the business simulation learning. As a prior research to the introduction and operation of the university's business simulation learning curriculum, the need and literature research on the possibility recognition of classes for college students and corporate executives, a demand survey research and analysis was done and discussed the necessity and possibility of the business simulation learning for the industry and universities education area. In addition, we designed a curriculum of the business simulation learning and presented some of education models of management for the university's management training purpose by using the results of the survey research and literature analysis.

• Journal of Korea Water Resources Association
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• v.46 no.2
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• pp.171-182
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• 2013

This paper presents the application of fuzzy set theory in multi criteria decision making (MCDM). FAHP (Fuzzy Analytic Hierarchy Process) method was used to rank alternatives to find the most reasonable and efficient way of agricultural reservoir water resources assessment. 6 criteria and 10 subcriteria had been identified and compared to secure agricultural water resources. Fuzzy numbers and linguistic variables were presented to address inherently uncertain or imprecise data. Comparison analysis of decision making method was also carried out to find a way of suitable decision making and validity of FAHP was discussed.