• Title/Summary/Keyword: centroid

검색결과 557건 처리시간 0.025초

NOTES ON GENERALIZED DERIVATIONS ON LIE IDEALS IN PRIME RINGS

  • Dhara, Basudeb;Filippis, Vincenzo De
    • 대한수학회보
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    • 제46권3호
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    • pp.599-605
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    • 2009
  • Let R be a prime ring, H a generalized derivation of R and L a noncommutative Lie ideal of R. Suppose that $u^sH(u)u^t$ = 0 for all u $\in$ L, where s $\geq$ 0, t $\geq$ 0 are fixed integers. Then H(x) = 0 for all x $\in$ R unless char R = 2 and R satisfies $S_4$, the standard identity in four variables.

GENERALIZED DERIVATIONS IN PRIME RINGS AND NONCOMMUTATIVE BANACH ALGEBRAS

  • De Filippis, Vincenzo
    • 대한수학회보
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    • 제45권4호
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    • pp.621-629
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    • 2008
  • Let R be a prime ring of characteristic different from 2, C the extended centroid of R, and $\delta$ a generalized derivations of R. If [[$\delta(x)$, x], $\delta(x)$] = 0 for all $x\;{\in}\;R$ then either R is commutative or $\delta(x)\;=\;ax$ for all $x\;{\in}\;R$ and some $a\;{\in}\;C$. We also obtain some related result in case R is a Banach algebra and $\delta$ is either continuous or spectrally bounded.

멀티캐스팅을 위한 BCT생성 알고리즘의 시뮬레이션 (A Simulation of BCT(Backbone Core Tree) Generation Algorithm for Multicasting)

  • 서현곤;김기형
    • 한국시뮬레이션학회:학술대회논문집
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    • 한국시뮬레이션학회 2002년도 춘계학술대회논문집
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    • pp.67-71
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    • 2002
  • 본 논문에서는 many-to-many IP 멀티캐스팅을 위한 효율적인 BCT(Backbone Core Tree)생성 알고리즘의 시뮬레이션 방법에 대하여 제안한다. BCT는 기법은 CBT(Core Based Tree)에 기반을 두고 있다. CBT는 공유 트리를 이용하여 멀티캐스트 자료를 전달하기 때문에 Source based Tree에 비하여 각 라우터가 유지해야 하는 상태 정보의 양에 적고, 적용하기 간단하지만, Core 라우터 선택의 어려움과 트래픽이 Core로 집중되는 문제점을 가지고 있다. 이에 대한 보완책으로 BCT기법이 제안되었는데, 본 논문에서는 주어진 네트워크 위상 그래프에서 최소신장 트리를 만들고, 센트로이드(Centroid)를 이용하여 효율적인 BCT를 생성하는 알고리즘을 제안하고 시뮬레이션 방법을 제시한다.

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신경회로망을 이용한 코드북의 순차적 갱신 알고리듬 (An Algorithm to Update a Codebook Using a Neural Net)

  • 정해묵;이주희;이충웅
    • 대한전자공학회논문지
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    • 제26권11호
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    • pp.1857-1866
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    • 1989
  • In this paper, an algorithm to update a codebook using a neural network in consecutive images, is proposed. With the Kohonen's self-organizing feature map, we adopt the iterative technique to update a centroid of each cluster instead of the unsupervised learning technique. Because the performance of this neural model is comparable to that of the LBG algorithm, it is possible to update the codebooks of consecutive frames sequentially in TV and to realize the hardwadre on the real-time implementation basis.

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차량 후면부의 번호판 추출 (Extraction of Car Plate at the Rear Side of Vehicle)

  • 김영백;박재윤;김원경
    • 한국지능시스템학회:학술대회논문집
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    • 한국퍼지및지능시스템학회 2004년도 추계학술대회 학술발표 논문집 제14권 제2호
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    • pp.564-567
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    • 2004
  • In this thesis, a method is proposed to extract the car plate at the rear side of vehicle using blobs. We first extract the blobs in the input images using intensity variations and calculate the minimum horde. rectangle (MBR) of each blobs. It is followed that we select groups of blobs having similar width, centroid. And then, we try to detect the border lines of car plate and verify whether the area is a car plate or not using NN.

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표식 인식 시스템의 개발 (Development of landmark tracking system)

  • 권승만;이상룡
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1991년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 22-24 Oct. 1991
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    • pp.642-645
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    • 1991
  • This paper presents the results of research on hardware and software of the landmark tracking system to the positions of moving robot in real time. The landmark tracking system is composed of CCD camera, landmark, strobo system and image processing board. The algorithm calculates the position and direction by using the coordinate transformation fomula after calculating the centroid and rotation angle of landmark at fixed position using the image data. The experiment is performed with landmark tracking system is loaded on xyz-table. XYZ-table is used for identifying the true position in our experiment. The results shows that this system has high performance with maxima error of .+-.1 pixels.

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PIV의 성능개선에 관한 연구 (A Study on the Improvement of PIV Performance)

  • 이영호;김춘식;최장운
    • Journal of Advanced Marine Engineering and Technology
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    • 제18권3호
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    • pp.34-42
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    • 1994
  • The present study is aimed to improve the PIV performance by suggesting a two-frame particle identification technique and by introducing estimation method of wall pressure distribution from the velocity data. Adopted image processing system consists of one commercial image board slit into a personal computer, 2-D sheet light generator, flow picture recording apparatus and related particle identification software. A revised particle tracking method essential to PIV performance is obtained by particle centroid correlation pairing (CCP) and its effectiveness is ascertained by comparison with multi-frame identification.

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격자형 환경 모델을 이용한 장애물의 의도 추론 (Obstacle's Intention Inference using the Grid-type Map)

  • 김성훈;이희영;변증남
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 1999년도 하계종합학술대회 논문집
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    • pp.796-799
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    • 1999
  • In this paper, we propose an inference method for understanding intention of obstacle for collision avoidance using the grid-type map. In order to represent the environment using ultrasonic sensors, the grid-type map is first constructed. Then we detect the obstacle and infer the intention for collision avoidance using the CLA(Centroid of Largest Area) point of the grid-type map. To verify the proposed method, some experiments are performed.

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Obtaining the driving scale of turbulence from observations

  • 조정연
    • 천문학회보
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    • 제42권1호
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    • pp.56.2-56.2
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    • 2017
  • To maintain turbulence in astrophysical fluids, driving is required. Constraining the driving scale of turbulence is important to identify the driving mechanism and also to obtain more accurate turbulence statistics from observations. We discuss how to obtain the driving scale of turbulence from observations. First, we explain the method to obtain the driving scale from the standard deviation of centroid velocity (i.e. the first moment of the line profile). Second, we discuss other techniques to obtain the driving scale.

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