• 제목/요약/키워드: Computational algorithms

검색결과 1,476건 처리시간 0.022초

컴퓨터 기하학을 위한 병렬계산 (Parallel Computing For Computational Geometry)

  • 오승준
    • 전자통신동향분석
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    • 제4권1호
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    • pp.93-117
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    • 1989
  • Computational Geometry is concerned with the design and analysis of computational algorithms which solve geometry problems. Geometry problems have a large number of applications areas such as pattern recognition, image processing, computer graphics, VLSI design and statistics since they involve inherently geometric problems for which efficient algorithms have to be developed. Several parallel algorithms, based on various parallel computation models, have been proposed for solving geometric problems. We review the current status of the parallel algorithms in computational geometry.

A Computational Approach to Definite NPs

  • Lee, Yong-Hun
    • 한국영어학회지:영어학
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    • 제3권1호
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    • pp.89-108
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    • 2003
  • As pronouns are resolved with their antecedents, definite NPs may enter into the anaphora-antecedent relations with indefinite NPs. This paper is to provide faster and more efficient computational algorithms by which definite NPs are resolved effectively, For this purpose, this paper extends Chierchia's Binding Theory in Categorial Grammar, and definite NPs are resolved with their antecedents by similar algorithms that are used to reflexive resolution. In these algorithms, the relations between indefinite NP and definite NP are represented with λ-expressions, and definite NPs are resolved with their antecedent by λ-conversions.

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New Error Control Algorithms for Residue Number System Codes

  • Xiao, Hanshen;Garg, Hari Krishna;Hu, Jianhao;Xiao, Guoqiang
    • ETRI Journal
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    • 제38권2호
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    • pp.326-336
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    • 2016
  • We propose and describe new error control algorithms for redundant residue number systems (RRNSs) and residue number system product codes. These algorithms employ search techniques for obtaining error values from within a set of values (that contains all possible error values). For a given RRNS, the error control algorithms have a computational complexity of $t{\cdot}O(log_2\;n+log_2\;{\bar{m}})$ comparison operations, where t denotes the error correcting capability, n denotes the number of moduli, and ${\bar{m}}$ denotes the geometric average of moduli. These algorithms avoid most modular operations. We describe a refinement to the proposed algorithms that further avoids the modular operation required in their respective first steps, with an increase of ${\lceil}log_2\;n{\rceil}$ to their computational complexity. The new algorithms provide significant computational advantages over existing methods.

에너지소산 제어 알고리듬의 제어이득 산정 (Control-Gain Estimation of Energy Dissipation Control Algorithms)

  • 이상현;민경원;강상훈
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 2004년도 봄 학술발표회 논문집
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    • pp.431-438
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    • 2004
  • This study is on control-gain estimation of energy dissipation control algorithms. Velocity feedback, bang-bang, and energy dissipation control algorithms are proposed based on the Lyapunov stability theory and their performances are evaluated and compared. Saturation problem is considered in the design of the velocity feedback and energy dissipation control algorithms, and chattering problem in bang-bang control is solved by using boundary layer. Numerical results show that the proposed control algorithms can dissipate the structural energy induced by wind loads efficiently, and thus provide good control performance.

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초등 예비교사의 컴퓨터과학에 대한 인식 변화를 위한 계산적 사고 기반 알고리즘 학습의 설계 및 적용 (Design and Application of Learning Algorithms based on Computational Thinking for Changes in Prospective Elementary School Teachers' Perceptions about Computer Science)

  • 김병수;김종훈
    • 수산해양교육연구
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    • 제24권4호
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    • pp.528-542
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    • 2012
  • In this study, we designed and applied the learning program of various algorithms about computer science, which were based on computational thinking, to prospective elementary school teachers who were non-majors of this field. While they were learning, they could understand two fundamental functions of computational thinking: abstraction and automation. This learning program made them change their perceptions about computer science positively. They had been interested in learning algorithms and computer science itself, and they felt confident about teaching it.

암호해독을 위한 양자 계산 알고리즘의 최근 연구동향 (Research Trends in Quantum Computational Algorithms for Cryptanalysis)

  • 배은옥;김정산;이수준
    • 한국광학회지
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    • 제29권2호
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    • pp.53-57
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    • 2018
  • 본 논문에서는 고전 계산 알고리즘에 비해 지수적인 계산 속도의 향상을 주는 양자 계산 알고리즘들을 중점적으로 소개하고, 기존 암호체계에 영향을 줄 수 있는 양자 계산 알고리즘 연구에 대한 최근 연구 성과들을 정리하며 최종적으로 이 결과들을 보다 발전적으로 향상시킬 수 있는 연구 방향을 제시한다.

3D 그래픽 S/W이용 초기 구조계획 (Preliminary Structural Configuration Using 3D Graphic Software)

  • 김남희;고현무;홍성걸
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 2011년도 정기 학술대회
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    • pp.504-507
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    • 2011
  • 3D graphic softwares have brought design spaces beyond the limitations of Euclidean space. Moreover, as computational geometry has been considered together with algorithms, generative algorithms are being evolved. Recently 3D graphic softwares with the embedded generative algorithms allow designers to design free form curves and surfaces in a systematic way. While architectural design has been greatly affected by the advancement of 3D graphic technology, such attention has not given in the realm of structural design. Grasshopper is a platform in Rhino to deal with these Generative Algorithms and Associative modelling techniques. This study has tried to develop a module for preliminary structural configuration using Rhino with Grasshopper. To verify the proposed concept in this study, a module for designing a basic type of suspension structure is introduced.

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Low-Complexity Sub-Pixel Motion Estimation Utilizing Shifting Matrix in Transform Domain

  • Ryu, Chul;Shin, Jae-Young;Park, Eun-Chan
    • Journal of Electrical Engineering and Technology
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    • 제11권4호
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    • pp.1020-1026
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    • 2016
  • Motion estimation (ME) algorithms supporting quarter-pixel accuracy have been recently introduced to retain detailed motion information for high quality of video in the state-of-the-art video compression standard of H.264/AVC. Conventional sub-pixel ME algorithms in the spatial domain are faced with a common problem of computational complexity because of embedded interpolation schemes. This paper proposes a low-complexity sub-pixel motion estimation algorithm in the transform domain utilizing shifting matrix. Simulations are performed to compare the performances of spatial-domain ME algorithms and transform-domain ME algorithms in terms of peak signal-to-noise ratio (PSNR) and the number of bits per frame. Simulation results confirm that the transform-domain approach not only improves the video quality and the compression efficiency, but also remarkably alleviates the computational complexity, compared to the spatial-domain approach.

3차원 일반 좌표계에서의 PISO, SIMPLE, SIMPLE-C 알고리즘의 비교 (A Comparative Study of PISO, SIMPLE, SIMPLE-C Algorithms in 3-dimensional Generalized Coordinate Systems)

  • 박준영;백제현
    • 한국전산유체공학회지
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    • 제1권1호
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    • pp.26-34
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    • 1996
  • The performance of the SIMPLE, SIMPLE-C and PISO algorithms for the treatment of the pressure-velocity coupling in fluid flow problems were examined by comparing the computational effort required to obtain the same level of the convergence. Example problems are circular duct and 90-degree bent square-duct. For circular duct case, laminar and turbulent flow were computed. For 90-degree bent square-duct case, laminar flow was simulated by the time-marching method as well as the iterative method. The convergence speed of the other two algorithms are not always superior to SIMPLE algorithm. SIMPLE algorithm is faster than SIMPLE-C algorithm in the simple laminar flow calculations. The application of the PISO algorithm in three dimensional general coordinates is not so effective as in two-dimensional ones. Since computational time of PISO algorithm is increased at each time step(or iterative step) in three dimension, the total convergence speed is not decreased. But PISO algorithm is stable for large time step by using time marching method,.

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주파수영역 적응필터의 수렴속도 향상을 위한 가변스텝사이즈 알고리즘에 관한 연구 (A study on Variable Step Size algorithms for Convergence Speed Improvement of Frequency-Domain Adaptive Filter)

  • 정희준;오신범;이채욱
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2000년도 추계종합학술대회 논문집(4)
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    • pp.191-194
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    • 2000
  • Frequency domain adaptive filter is effective to communication fields of many computational requirements. In this paper we propose a new variable step size algorithms which improves the convergence speed and reduces computational complexity for frequency domain adaptive filter. we compared MSE of the proposed algorithms with one of normalized FLMS using computer simulation of adaptive noise canceler based on synthesis speech.

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