• 제목/요약/키워드: Minimum Euclidean distance

검색결과 56건 처리시간 0.022초

AN UPPER BOUND ON THE NUMBER OF PARITY CHECKS FOR BURST ERROR DETECTION AND CORRECTION IN EUCLIDEAN CODES

  • Jain, Sapna;Lee, Ki-Suk
    • 대한수학회지
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    • 제46권5호
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    • pp.967-977
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    • 2009
  • There are three standard weight functions on a linear code viz. Hamming weight, Lee weight, and Euclidean weight. Euclidean weight function is useful in connection with the lattice constructions [2] where the minimum norm of vectors in the lattice is related to the minimum Euclidean weight of the code. In this paper, we obtain an upper bound over the number of parity check digits for Euclidean weight codes detecting and correcting burst errors.

Optimum Convolutional Error Correction Codes for FQPSK-B Signals

  • Park, Hyung-Chul
    • 한국통신학회논문지
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    • 제29권5C호
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    • pp.611-617
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    • 2004
  • The optimum convolutional error correction codes for recently standardized Feher-patented quadrature phase-shift keying (FQPSK-B) modulation are proposed. We utilize the continuous phase modulation characteristics of FQPSK-B signals for calculating the minimum Euclidean distance of convolutional coded FQPSK-B signal. It is shown that the Euclidean distance between two FQPSK-B signals is proportional to the Hamming distance between two binary data sequence. Utilizing this characteristic, we show that the convolutional codes with optimum free Hamming distance is the optimum convolutional codes for FQPSK-B signals.

최단거리에 기반한 시계열 데이타의 효율적인 유사 검색 (Efficient Similarity Search in Time Series Databases Based on the Minimum Distance)

  • 이상준;권동섭;이석호
    • 한국정보과학회:학술대회논문집
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    • 한국정보과학회 2003년도 봄 학술발표논문집 Vol.30 No.1 (A)
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    • pp.533-535
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    • 2003
  • The Euclidean distance is sensitive to the absolute offsets of time sequences, so it is not a suitable similarity measure in terms of shape. In this paper. we propose an indexing scheme for efficient matching and retrieval of time sequences based on the minimum distance. The minimum distance can give a better estimation of similarity in shape between two time sequences. Our indexing scheme can match time sequences of similar shapes irrespective of their vortical positions and guarantees no false dismissals

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최소해밍거리를 이용한 트렐리스 부호화된 M- ray PSK의 성능 향상 (Performance Enhancement of Trellis Coded Mary PSK using Minimum Hamming Distance)

  • 은도현;조훈상;이순흠
    • 한국전자파학회논문지
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    • 제12권3호
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    • pp.417-424
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    • 2001
  • 본 논문은 부가 백색 가우시안 잡음 채널에서 M-ary PSK 트렐리스 부호화변조기법의 비트 오차 성능을 향상시키기 위하여 기존의 심볼사상방법에 비해 개선된 오류특성을 나타낼 수 있는 새로운 심볼사상방법을 제안하고 그 성능향상을 확인한 내용을 담고 있다. 본 논문에서 제안된 새로운 심볼사상방법은 셋분할 하는 경우 유클리드 거리뿐 아니라 해밍거리도 고려한 심볼사상방법으로 본 방법에 의한 성능향상을 기존 방식과 비교하여 수식을 이용한 분석한 컴퓨터 시뮬레이션을 통해 검증하였다.

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원호와직선으로 구성된 도형간의 효율적인 최소거리 계산방법 (An Efficient Method for Minimum Distance Problem Between Shapes Composed of Circular Arcs and Lines)

  • 김종민;김민환
    • 대한전기학회논문지
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    • 제43권5호
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    • pp.848-860
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    • 1994
  • Generally, to get the minimum distance between two arbitrary shapes that are composed of circular arcs and lines, we must calculate distances for all the possible pairs of the components from two given shapes. In this paper, we propose an efficient method for the minimum distance problem between two shapes by using their structural features after extracting the reduced component lists which are essential to calculate the minimum distance considering the relationship of shape location. Even though the reduced component lists may contain all the components of the shapes in the worst case, in the average we can reduce the required computation much by using the reduced component lists. This method may be efectively applied to calculating the minimum distance between two shapes which are generated by the CAD tool, like in the nesting system.

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Minimum Distance based Precoder Design for General MIMO Systems using Gram Matrix

  • Chen, Zhiyong;Xu, Xiaodong
    • Journal of Communications and Networks
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    • 제17권6호
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    • pp.634-646
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    • 2015
  • Assuming perfect channel state information (CSI) at the transmitter and receiver, the optimization problem of maximizing the minimum Euclidean distance between two received signals by a linear precoder is considered for multiple-input multiple-output (MIMO) systems with arbitrary dimensions and arbitraryary quadrature amplitude modulation (QAM) input. A general precoding framework is first presented based on the Gram matrix, which is shown for 2-dimensional (2-D) and 3-dimensional (3-D) MIMO systems when employing the ellipse expanding method (EEM). An extended precoder for high-dimensional MIMO system is proposed following the precoding framework, where the Gram matrix for high-dimensional precoding matrix can be generated through those chosen from 2-D and 3-D results in association with a permutation matrix. A complexity-reduced maximum likelihood detector is also obtained according to the special structure of the proposed precoder. The analytical and numerical results indicate that the proposed precoder outperforms the other precoding schemes in terms of both minimum distance and bit error rate (BER).

고유영상 투영거리를 이용한 얼굴영상 검색 (Face Image Retrieval by Using Eigenface Projection Distance)

  • 임길택
    • 한국산업정보학회논문지
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    • 제14권5호
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    • pp.43-51
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    • 2009
  • 본 논문에서는 PCA(principal component analysis)기반의 특징을 이용한 효율적인 얼굴검색 방법을 제안한다. coarse-to-fine 전략을 사용하여 저차원 고유얼굴 공간에서 검색 결과들을 1차 정렬한 후 상위 후보들을 확장된 차원의 고유얼굴 공간에서 재정렬하는 방식으로 검색 순위를 재조정한다. 질의 영상과 클래스간의 유사도의 측정을 위해 PD(projection distance), MQDF(modified quadratic distance function), MED(minimum Euclidean distance)를 사용한다. 실험 결과 $32{\times}32$ 크기의 질의 영상에 PD를 활용하여 점진적으로 검색 결과를 조정하는 제안하는 방법이 얼굴검색에 효율적임을 알 수 있었다.

비중 상한 제약조건에 따른 포트폴리오 성과에 대한 투자 비중 분석 (Weight Vector Analysis to Portfolio Performance with Diversification Constraints)

  • 박경찬;김홍선;김성문
    • 경영과학
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    • 제33권4호
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    • pp.51-64
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    • 2016
  • The maximum weight of single stock in mutual fund is limited by regulations to enforce diversification. Under incomplete information with added constraints on portfolio weights, enhanced performance had been reported in previous researches. We analyze a weight vector to examine the effects of additional constraints on the portfolio's performance by computing the Euclidean distance from the in-sample tangency portfolio, as opposed to previous researches which analyzed ex-post return only. Empirical experiment was performed on Mean-variance and Minimum-variance model with Fama French's 30 industry portfolio and 10 industry portfolio for the last 1,000 months from August 1932 to November 2015. We find that diversification-constrained portfolios have 7% to 26% smaller Euclidean distances with the benchmark portfolio compared to those of unconstrained portfolios and 3% to 11% greater Sharpe Ratio.

Cluster의 중심벡터를 이용하는 영상 압축 (The Image Compression Using the Central Vectors of Clusters)

  • 조제황
    • 한국음향학회지
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    • 제14권1호
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    • pp.5-12
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    • 1995
  • Training 벡터 집합이 Cluster를 이루는 경우, 벡터 양자화에서 영상과 음성의 압축에 사용되는 코드북의 코드벡터는 Cluster의 중심벡터로 간주된다. 본 연구에서는 Training 벡터 간의 Euclidean 거리가 최소가 되는 벡터를 찾는 과정에서 얻어지는 Euclidean 거리분포를 관찰하여 적절한 Cluster수와 그 중심벡터를 결정할 수 있는 방법을 제시하고, 제안된 방법이 기존의 LBG 알고리즘이나 Competitive 학습 알고리즘에 의한 영상 압축보다 약 4[dB] 이상 향상된 SNR을 얻을 수 있음을 보인다.

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Fixed bias를 가지는 4-D Multiple-Subcarrier 신호를 이용한 Optical Wireless 통신의 평균 전력 절감에 관한 연구 (Fixed Biased 4-D Multiple-Subcarrier Signal for Average Power Reduction in Optical Wireless Communication)

  • 김해근
    • 대한전자공학회논문지TC
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    • 제40권10호
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    • pp.103-109
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    • 2003
  • 기존의 Multiple-Subcarrier변조 방식에 4-차원(4-D)신호를 이용한 Optical Wireless통신 방식을 제안하였다. 4-D 신호는 신호파형 최적화 기술 (OSW, Optimization Technique of Signal Waveforms)을 이용하여 유도하고 Multiple-Subcarricr의 block coder에 적용함으로써 출력 신호점 간의 Euclidean distance를 최대화하였다. 그 결과 고정 dc 바이어스를 부가한 상태에서 시스템에서 요구되는 Normalized power를 QPSK에 비해 3 dB, Reserved Subcarrier 나 Minimum Power에 비해 최대 3.3 dB 를 각각 절감하였고 normalized bandwidth 1.125 ∼ 1.25의 범위에서 QPSK에 비해 평균 3 dB, Res. Subcarrier 방식에 비해 2 ∼ 4 dB, Min. Power 방식에 비해 0 ∼ 3 dB를 각각 절감하였다.