• 한국지능시스템학회논문지
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• 제14권6호
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• pp.674-677
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• 2004

본 논문에서는 심볼간의 간섭이 존재하는 채널에서 고정 지연 값을 가지는 트리검색 신호검출기의 효율적인 구성방법을 다룬다. 이 접근방법은 효율적인 다차원 신호공간 분할에 기반을 두고 있다 다차원 공간에서의 Voronoi 다이어그램 (VoD)과 Delaunay 분할 (DT)이 신호검출 알고리즘의 구현에 적용된다 제안된 방식에서는 VOD/DT에 포함되어 있는 기하학적인 정보를 활용하여 관찰된 순차적인 신호의 상대적인 위치가 결정되며 이러한 방식이 구현치 복잡도를 감소시키는 장점이 있음을 보인다. 구체적인 구성 절차가 심볼간의 간섭이 존재하는 통신채널에서의 예를 가지고 논의되며 시뮬레이션 결과가 논의된다.

• 한국농촌건축학회논문집
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• 제22권3호
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• pp.9-16
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• 2020

The trend emphasizes children-oriented, play-oriented ecological education programs for children's ecological education. And most of these nature -friendly and eco-friendly education takes place outdoors. Therefore, outdoor space planning is important in childcare facilities. This case study aims to analyze the actual conditions of outdoor spaces in daycare centers and to provide standard data for outdoor space planning. In order to provide basic data on the improvement direction and planning standards of outdoor spaces, this present study conducted the composition, utilization status and related problems of outdoor spaces for nature -friendly ecological education in childcare facilities. Accordingly, outdoor space planning for ecological education should consider outdoor space characteristics such as free and easy accessibility between indoor and outdoor spaces, openness of space, flexibility, dynamic/static space, and nature affinity. Therefore, for an ecological education environment, children should be able to freely approach nature and play in the natural environment without any restrictions and artificial controls. Also, in urban areas, natural environment such as parks and open spaces should be considered as outdoor play spaces for children.

• 대한기계학회논문집A
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• 제34권8호
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• pp.989-996
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• 2010

통계적 회귀모델과 보간모델은 구조공학 분야에서 실제실험과 전산실험의 결과로부터 자료를 분석하고 응답을 예측하기 위해 적용되었으며 최근 10 년 동안 다양한 설계방법론들과 함께 발전해왔다. 그러나 그들은 구조물의 크기와 형상과 같은 공간변수에 대해서만 취급해왔고 시간변수에 따라 변하는 시간-변화 동적응답을 고려할 수 없었다. 본 연구에서는 공간변수와 시간변수를 모두 취급하여 시간-변화 동적응답을 고려할 수 있는 다중응답접근법 기반 통계적 공간-시간 메타모델을 제안한다. 대표적 회귀모델인 반응표면모델과 보간모델인 크리깅모델을 구조공학 예제의 시간-변화 동적응답에 적용한다. 또한 제안한 방법의 성능을 검증하기 위해 실제함수와의 비교를 통해 두 통계적 공간-시간 메타모델의 정확성을 비교한다.

• Journal of Astronomy and Space Sciences
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• 제31권1호
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• pp.33-39
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• 2014

This paper describes an experimental approach to evaluate the effective doses of space radiations at high-altitude by combining the measured data from the Liulin-6K spectrometer loaded onto the air-borne RC-800 cockpit and the calculated data from CARI-6M code developed by FAA. In this paper, 15 exposed dose experiments for the flight missions at a high-altitude above 10 km and 3 experiments at a normal altitude below 4 km were executed over the Korean Peninsula in 2012. The results from the high-altitude flight measurements show a dramatic change in the exposed doses as the altitude increases. The effective dose levels (an average of $15.27{\mu}Sv$) of aircrew at the high-altitude are an order of magnitude larger than those (an average of $0.30{\mu}Sv$) of the normal altitude flight. The comparison was made between the measure dose levels and the calculated dose levels and those were similar each other. It indicates that the annual dose levels of the aircrew boarding RC-800 could be above 1 mSv. These results suggest that a proper procedure to manage the exposed dose of aircrew is required for ROK Air Force.

• Journal of the Korean Data and Information Science Society
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• 제15권4호
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• pp.759-771
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• 2004

The decision tree approach is most useful in classification problems and to divide the search space into rectangular regions. Decision tree algorithms are used extensively for data mining in many domains such as retail target marketing, fraud dection, data reduction and variable screening, category merging, etc. We analyze Gyeongnam social indicator survey data using decision tree techniques for environmental information. We can use these decision tree outputs for environmental preservation and improvement.

• Industrial Engineering and Management Systems
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• 제13권4호
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• pp.369-382
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• 2014

This paper introduces a new multi-product multi-period multi-objective aggregate production planning problem. The proposed problem is modeled using multi-objective mixed-integer mathematical programming. Three objective functions, including minimizing total cost, maximizing customer services level, and maximizing the quality of end-product, are considered, simultaneously. Several constraints such as quantity of production, available time, work force levels, inventory levels, backordering levels, machine capacity, warehouse space and available budget are also considered. Some parameters of the proposed model are assumed to be qualitative and modeled using fuzzy sets. Then, a fuzzy goal programming approach is proposed to solve the model. The proposed approach is applied on a real-world industrial case study of a color and resin production company called Teiph-Saipa. The approach is coded using LINGO software. The efficacy and applicability of the proposed approach are illustrated in the case study. The results of proposed approach are compared with those of the existing experimental methods used in the company. The relative dominance of the proposed approach is revealed in comparison with the experimental method. Finally, a data dictionary, including the way of gathering data for running the model, is proposed in order to facilitate the re-implementation of the model for future development and case studies.

• 한국항공우주학회지
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• 제34권10호
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• pp.1-6
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• 2006

본 연구에서는 3차원 날개의 실속 특성을 예측하였다. 날개의 실속 특성을 해석하기 위해 반복적 캠버변형 기법을 비평면 양력면 이론에 도입하였다. 반복적 캠버변형 기법은 기지의 2차원 에어포일 데이터를 이용하여 3차원 날개의 실속 특성을 해석한다. 날개의 한 단면에서의 캠버변형이 날개의 다른 단면에 미치는 영향은 다차원 뉴턴 반복법을 사용하여 고려하였다. 해석 결과는 실험값과 타 전산해석 결과와 비교하여 일치되는 결과를 보였다. 본 기법은 비틀림 또는 조종면을 갖는 어떠한 날개에도 적용이 가능하며 또한 날개와 날개의 상호 작용이 있을 때의 실속 특성도 예측 가능하다.

• Journal of Sport and Applied Science
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• 제4권4호
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• pp.7-17
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• 2020

Purpose: This study started with interest in sport culture and is meaningful as an exploratory study to help with the basic understanding of sport culture research. Research design, data, and methodology: The approach of this study is the exploratory approach by literature reviews. This study carried out exploratory research on thinking about diversity of sports culture and the development process of sports culture by human history periods. Results: First, in thinking about cultural diversity, cultural absolutism and cultural relativism were identified. The characteristics of sports culture can identify universality, individuality and diffusion, and the attributes of sports culture included sharing, learning, accumulation, whole systematic relationship and change. Second, the characteristics of sports culture were identified by the approach of each historical era. The historical stages were divided into ancient civilizations, ancient Greece and Rome, middle ages and early modern period, and late modern period. Sports have historically been found to have a British-centered European origin or popularized in the United States. Conclusions: with the characteristics of modern sports culture, the globalization of sports culture, the prominence of sports industry and sports space marketing, and the symbiotic influence relationship of sports and mass media were examined and future directions were discussed.

• 한국주거학회논문집
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• 제12권3호
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• pp.1-12
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• 2001

The purpose of this study was to investigate the outdoor space of the recent built apartment complex in Ulsan and to provide the basic information for planning and apartment outdoor space. Multiple methods were utilized such as questionnaire, observation, behavior-mapping, and photography. The sample consisted of 382 residents living in four apartment complex in Ulsan. data were analyzed by frequency and percentage using SPSS PC+. The observation was performed in seven outdoor space, i.e., green area, road area, exercise area, play area, parking area, and approach area. According to the findings of this study, residents did not actively involve in outdoor activities and seldom use the outdoor space. Various changes and erosions were observed as a trace, especially near fence and grass area because of unplanned location of entrances. Finally this study suggested several planning guidelines for outdoor space in apartment complex.

• 천문학회보
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• 제46권2호
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• pp.59.2-59.2
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• 2021

On March 6 2021, Apophis made a close approach to the Earth with a minimum distance of 0.11 AU when the apparent magnitude reached up to V~16. This was the most favorable condition to observe this asteroid until its 2029 encounter. The observations during this apparition were extremely important to determine major physical properties, such as size, rotational state, 3D shape model, surface mineral properties. So, we organized the observation campaign during the 2021 apparition. The main goals of our campaign are to refine the spin state and 3D shape model and check the surface composition variations. The campaign involved dozens of countries and included ground-based photometry and spectroscopy, and spacecraft observations. Our timely observation campaign will provide essential data in planning the operation scenario for the space mission. In this presentation, we will report the preliminary result of the Apophis observation campaign during the 2021 apparition.