• 제목/요약/키워드: design diversity

검색결과 1,026건 처리시간 0.022초

OFDM-CDMA기반의 광대역 무선접속시스템에서 공간-시간부호의 성능분석 (Performance Analysis of Space-Time Codes on OFDM-CDMA based Broadband Wireless Access Networks)

  • 강민구
    • 인터넷정보학회논문지
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    • 제7권1호
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    • pp.173-178
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    • 2006
  • 본 논문에서는 OFDM-CDMA기반의 광대역 무선 접속시스템에서 다중 안테나를 적용한다. 이로서 시간영역에서 윈도우 기반의 채널추정 기법과 OFDM기반의 공간영역에서 다중 안테나 전송시스템에서 채널추정의 불완전성을 극복하기 위한 다채널 분리용 프리앰블을 적용함으로서 광대역 무선 접속시스템에서 사용자수를 최대로 확대하고 사용자 용량을 증대하는 광대역 무선접속시스템의 성능을 분석하였다.

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Discrete optimal sizing of truss using adaptive directional differential evolution

  • Pham, Anh H.
    • Advances in Computational Design
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    • 제1권3호
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    • pp.275-296
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    • 2016
  • This article presents an adaptive directional differential evolution (ADDE) algorithm and its application in solving discrete sizing truss optimization problems. The algorithm is featured by a new self-adaptation approach and a simple directional strategy. In the adaptation approach, the mutation operator is adjusted in accordance with the change of population diversity, which can well balance between global exploration and local exploitation as well as locate the promising solutions. The directional strategy is based on the order relation between two difference solutions chosen for mutation and can bias the search direction for increasing the possibility of finding improved solutions. In addition, a new scaling factor is introduced as a vector of uniform random variables to maintain the diversity without crossover operation. Numerical results show that the optimal solutions of ADDE are as good as or better than those from some modern metaheuristics in the literature, while ADDE often uses fewer structural analyses.

옥상 녹화지의 시각적 선호도 (Visual Preference in Green Roof Sites)

  • 이관규
    • 한국조경학회지
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    • 제34권5호
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    • pp.32-38
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    • 2006
  • Roof greening in a city can contributes to not only providing network opportunities for dispersed greenspace patches but also bringing more greenspaces into a city. In addition, it can help to flooding and microclimate control in the city. Recently, a number of roof greening projects have been introduced, mainly to public buildings and schools. Roof peening need to offers both ecological functions and convenience and satisfaction for urban residents. This study aims to provide directions for improving ecological benefits and visual preference of roof greening. Twelve scene slides were adopted to measure people's visual preference. The survey results show that landscape images can be categorized into naturalness, visual diversity, uniqueness, and spatial flexibility. Physical scenes can be classified into type I mostly greened by plants, type II mixed between convenience facilities and plants, and type III constructed with pond. People show high preferences to type I and type II when visual diversity is high. The results of this study suggest to enhance the visual preference by considering visual diversity when applying the ecological design methods to improve naturalness for roof greening.

다이버시티 안테나의 소형화와 격리도 향상을 위한 미앤더 선로와 개방형 루프가 결합된 방사구조의 설계 (Design of the Open-Loop Combined Meandered-Line 1-Layer Radiator for Diversity Antennas with Size-Reduction and Improved Isolation)

  • 목세균;강승택;김용진
    • 전기학회논문지
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    • 제61권1호
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    • pp.110-116
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    • 2012
  • This paper proposes a new diversity antenna which is the base of MIMO, tunable and reconfigurable antennas. The antenna has a small size and high inter-antenna isolation resulting from the compact radiating element comprising a meandered line and an open-loop combined in one limited uniplanar space and a modified T-shaped decoupling structure, respectively. In a WiMAX band, the radiating element and the entire antenna are $0.092{\lambda}$ and $0.2216{\lambda}$ in size, which shows effective size-reduction and the gain and efficiency of the proposed antenna attached to the ground of a handheld device are 3.7dBi and 56% acceptable to the industrial standard.

생태학적 원리를 적용하여 창조된 환경림에서 확인된 복원 효과 (Restoration Effects Confirmed in the Environmental Forests Created on the Bases of Ecological Principles)

  • 이창석;이안나
    • 환경생물
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    • 제22권1호
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    • pp.220-226
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    • 2004
  • 경기도 시흥시 정왕동 시화공업단지 내 주식회사 진도종합건설 시화소각장 주변을 생태적으로 건전하게 유지하기 위한 수단으로 생태적 설계에 바탕을 두고 복원사업을 실시하였고, 서울시 노원구의 수락산에 인공 조림된 아까시나무 임분을 복원생태학의 원리에 바탕을 두고 관리하여 그 효과를 평가하였다. 생태학적으로 창조된 숲은 조경 방법을 적용하여 조성된 숲과 비교하여 주변의 자연림과 더 유사한 종 조성을 나타내었고, 종 다양성도 높아 생태적 복원의 효과가 확인되었다. 생태학적 원리를 적용하여 관리된 아까시나무 임분은 그러한 관리없이 방치된 것과 비교하여 인근의 자연림과 더 유사한 종 조성을 나타내었고, 종 다양성도 높아 여기서도 복원의 효과를 확인할 수 있었다. 그러나 이러한 생태적 복원은 사업시행자 및 감독자의 전문성 결여, 생태적 특성이 반영되지 않은 건축조례, 묘목의 부재 등 여러 가지 현실적 문제점을 드러내었다. 본 연구는 이러한 문제를 해결하기 위한 대안으로 건축조례의 개선을 포함하여 해당지역의 자연환경에 토대를 둔 식재 지침 마련, 묘목의 준비 및 국민의 의식 수준을 향상시키기 위한 환경교육의 필요성을 제시하였다.

여대생의 메이크업행동에 관한 연구 (A Study on the Behavior of women Student in the University about Make-up)

  • 이난희;이상은
    • 한국의상디자인학회지
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    • 제7권2호
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    • pp.87-99
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    • 2005
  • This study is to examine the modern women's awareness make-up in psychological standpoint based upon the survey of $20\~30$ years old women's consciousness of the motivation, the attention, the psychological utility, the attitude for make-up, the action behavior and the coordination with clothes. Modern women show a keen interest in make-up in company with the diversity of a fashion. This means the tendency which the intention for change and the expression of oneself are emphasizing on. The motivations of make-up are women's attention to other people and notice of evaluation of others and social meaning of make-up in relation with one's interest in appearances. Also, total coordination is concerned as another motivation. Make-up became the practical use and usual doings for women with the diversity of the information of make-up & the increase of cosmetics. Since there were so many women responded that they start to make up in their teens, we recognized that the women's sense of values has changed with the change of modern society.

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개선된 ABAB 형 준직교 시공간 블록 부호 (Improved ABAB Type Quasi-orthogonal Space-Time Block Codes)

  • 김창중;여승준;이호경
    • 대한전자공학회논문지TC
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    • 제46권4호
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    • pp.70-76
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    • 2009
  • 본 논문에서는 ABAB 형 준직교 시공간 부호(Quasi-Orthogonal Space-Time Block Code; QOSTBC)에 사용되는 전처리 과정을 설계하는 조건을 제안하였다. 본 논문에서 제안한 설계 조건은 최대 다이버시티 및 최대 전송율(Full Diversity and Full Rate; FDFR), 단일 심볼 복호 능력, 향상된 부호 이득을 얻을 수 있는 방법을 제공한다. 또한 본 논문에서는 제안된 설계 조건을 이용하여 개선된 ABAB 형 QOSTBC를 설계하였다. 이 QOSTBC는 기존에 Dalton이 제안했던 ABAB 형 QOSTBC 부호 보다 뛰어난 성능을 가질 뿐 아니라, 동일하게 FDFR을 충족하며, PAM 신호 성좌가 사용되는 경우, 단일 심볼 복호가 가능하다.

A Modularized Approach to the Development of the Creativity Learning Program

  • Won, Kyung-Ah
    • 디자인학연구
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    • 제20권2호
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    • pp.103-116
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    • 2007
  • Art education in design has repeatedly stressed the importance of developing creativity. In the digital period, however, which shows rapid change in both forms and contents, it needs to be equipped with more flexible and systematic ways of approaching to the creativity development, especially involved with cultural diversity of the digital world. This paper primarily proposes a maximally efficient, productive creativity learning program in which the integration of expressive media and communication generates a comprehensive network of communicative information in the development of digital technologies, which, consequently, brings forth valuable cultural contents of art. The amalgamation of Won (2006)'s Prism Effect, with distinctive three devices, and the facilitator factors, with two different facilitators such as self-controlled and controlled plays, would function as a catalyst for cultural diversity in the digital forms and contents of art. And this will, consequently, result in producing a number of practices that can be classified and assorted for a later performance. This paper thus suggests a roadmap of how to develop the creativity learning program in which two categories of facilitators based on three thinking devices function to classify four activities. In addition, selected activities are shaped as a creativity learning program by generating learning practices with the formalizing instructional strategy that fit into a specialized educational environment and learners. The samples of loaming practice design show guidelines for practice and the results of learning activity. Therefore, the eventual goal of this paper would be to establish a creativity learning program that constitutes a highly systematized and modularized database to maximize the efficiency and productivity of the creativity development.

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$\varepsilon$-다중목적함수 진화 알고리즘을 이용한 DNA 서열 디자인 (DNA Sequence Design using $\varepsilon$ -Multiobjective Evolutionary Algorithm)

  • 신수용;이인희;장병탁
    • 한국정보과학회논문지:소프트웨어및응용
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    • 제32권12호
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    • pp.1217-1228
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    • 2005
  • 최근 들어 DNA 컴퓨팅이 활발하게 연구되면서, DNA 컴퓨팅에서 가장 기본적이고도 중요한 DNA 서열 디자인 문제가 부각되고 있다. 기존의 연구에서 DNA 서열 디자인 문제를 다중목적 최적화 문제로 정의하고, elitist non-dominated sorting genetic algorithm(NSGA-II)를 이용하여 성공적으로 DNA 서열을 디자인하였다. 그런데, NSGA-II는 계산속도가 느리다는 단점이 있어서, 이를 극복하기 위해 본 논문에서는 $\varepsilon$-다중목적함수 진화알고리즘(r-Multiobjective evolutionary algorithm, $\varepsilon$-MOEA)을 DNA 서열 디자인에 이용하였다. 우선, 두 알고리즘의 성능을 보다 자세히 비교하기 위해서 DTLZ2 벤치 마크 문제에 대해서 적용한 결과, 목적함수의 개수가 작은 경우에는 큰 차이가 없으나, 목적함수의 개수가 많을 경우에는 $\varepsilon$-MOEA가 NSGA-II에 대해서 최적해를 찾는 정도(Convergence)와 다양한 해를 찾는 정도 (diversity)에 있어서 각각 $70\%,\;73\%$ 향상된 성능을 보여주었고, 또한 최적해를 찾는 속도도 비약적으로 개선되었다. 이러한 결과를 바탕으로 기존의 DNA 서열 디자인 방법론으로 디자인된 DNA 서열들과 7-순환외판원 문제 해결에 필요한 DNA 서열을 NSGA-II와 $\varepsilon$-MOEA로 재디자인하였다. 대부분의 경우 $\varepsilon$-MOEA가 우수한 결과를 보였고, 특히 7-순환외판원 문제에 대해서 NSGA-II와 비교하여 convergence와 diversity의 측면에서 유사한 결과를 2배 이상 빨리 발견하였고, 동일한 계산 시간을 이용해서는 $22\%$ 정도 보다 다양하게 해를 발견하였으며, $92\%$ 우수한 최적해를 발견하는 것을 확인하였다.

현대 패션에 나타난 '느림'의 패러다임 (Fashion Paradigm of 'Slowness' on Contemporary Fashion)

  • 함연자
    • 한국의류산업학회지
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    • 제11권4호
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    • pp.527-536
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    • 2009
  • The purpose of this study is to consider the characteristics of fashion paradigm on contemporary fashion in pursuit of social change towards 'slowness'. As for the research methodology, literature survey has been undertaken. The results of this study can be summarized as followings. First, eco-friendly ethics towards sustainability is in taking action. The concept of 'cradle-to-cradle' is realized through reuse, recycle, organic material, and no use of chemical. Second, local diversity is revolving quality and longevity. Good quality of fashion made by artisans and specificity in local area is to be kept last. Third, people are recast in roles from simple consumers to self-made producers of their clothes. Users of clothes are more active and skilled role in practice of handmade, reform, DIY, and open-source design. In Conclusion, the fashion paradigm of 'slowness' is about designing, producing, consuming and living better to combine ideas for sense of nature's time, culture's time and people's time.