• 제목/요약/키워드: point sampling

검색결과 824건 처리시간 0.032초

계층적인 탐색점 추출을 이용한 고속 블록 정합 알고리즘 (A Fast Block Matching Algorithm Using Hierarchical Search Point Sampling)

  • 정수목
    • 한국컴퓨터산업학회논문지
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    • 제4권12호
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    • pp.1043-1052
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    • 2003
  • 본 논문에서는 비디오코딩의 움직임 추정을 위한 빠른 움직임 추정알고리즘을 제안하였다. 제안된 알고리즘은 다단계 연속제거 알고리즘과 효율적인 다단계 연속제거 알고리즘에 기초하고 있다. 제안된 알고리즘은 계층적으로 탐색점을 추출하여 매우 많은 연산량을 필요로 하는 정합 연산량을 감소시키면서 최상의 움직임벡터를 얻을 수 있다. 실험을 통하여 제안된 알고리즘의 효율성을 확인하였다.

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Bayesian Parameter Estimation using the MCMC method for the Mean Change Model of Multivariate Normal Random Variates

  • Oh, Mi-Ra;Kim, Eoi-Lyoung;Sim, Jung-Wook;Son, Young-Sook
    • Communications for Statistical Applications and Methods
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    • 제11권1호
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    • pp.79-91
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    • 2004
  • In this thesis, Bayesian parameter estimation procedure is discussed for the mean change model of multivariate normal random variates under the assumption of noninformative priors for all the parameters. Parameters are estimated by Gibbs sampling method. In Gibbs sampler, the change point parameter is generated by Metropolis-Hastings algorithm. We apply our methodology to numerical data to examine it.

새만금 예정수역의 수질특성 조사 (Study on the Characteristics for Water Quality in Prearranged Saemangeum Reclaiming Area)

  • 이광야;엄명철;조재원;정해진
    • 한국농공학회:학술대회논문집
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    • 한국농공학회 2003년도 학술발표논문집
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    • pp.555-558
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    • 2003
  • This study carried out to analyze the characteristics of water concentration for Saemangeum reclaiming area during two seasons. Total nitrogen appeared by thing which all mean values are the biggest at two survey at ST.4 that is near with Mangyoung river. At the same time, change by range of tide was seen. Therefore, is thought that ST.4 suffers impact of river and seawater at the same time. But is thought that water of Mangyoung river exerts bigger effect than seawater because ST.4 appears that concentration is high clearly with different Sampling point. Therefore, is thought that pollution occurs better than different sampling point if ST.4's flowing deters.

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Probability Constrained Search Range Determination for Fast Motion Estimation

  • Kang, Hyun-Soo;Lee, Si-Woong;Hosseini, Hamid Gholam
    • ETRI Journal
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    • 제34권3호
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    • pp.369-378
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    • 2012
  • In this paper, we propose new adaptive search range motion estimation methods where the search ranges are constrained by the probabilities of motion vector differences and a search point sampling technique is applied to the constrained search ranges. Our new methods are based on our previous work, in which the search ranges were analytically determined by the probabilities. Since the proposed adaptive search range motion estimation methods effectively restrict the search ranges instead of search point sampling patterns, they provide a very flexible and hardware-friendly approach in motion estimation. The proposed methods were evaluated and tested with JM16.2 of the H.264/AVC video coding standard. Experiment results exhibit that with negligible degradation in PSNR, the proposed methods considerably reduce the computational complexity in comparison with the conventional methods. In particular, the combined method provides performance similar to that of the hybrid unsymmetrical-cross multi-hexagon-grid search method and outstanding merits in hardware implementation.

Deciding a sampling length for estimating the parameters in Geometric Brownian Motion

  • Song, Jun-Mo
    • Journal of the Korean Data and Information Science Society
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    • 제22권3호
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    • pp.549-553
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    • 2011
  • In this paper, we deal with the problem of deciding the length of data for estimating the parameters in geometric Brownian motion. As an approach to this problem, we consider the change point test and introduce simple test statistic based on the cumulative sum of squares test (cusum test). A real data analysis is performed for illustration.

A High Quality Mesh Generation for Surfaces in the Use of Interval Arithmetic

  • Kikuchi, Ryota;Makino, Mitsunori
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2002년도 ITC-CSCC -2
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    • pp.1153-1156
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    • 2002
  • In this parer, a high quality mesh generation method by using interval arithmetic is proposed. In the proposed method, the variance of a tangent vector at the point is considered by the automatic differentiation. From the variance, sampling points on the surface are judged whether it is adequate or not, which is calculated by the interval arithmetic. Then Delaunay triangulation is performed to the obtained sampling points, and a set of meshes is generated. The proposed method is hard to overlook the local variation of surfaces.

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특이점의 분할을 고려한 근사 서브디비전 방법에 대한 연구 (A Study on approximating subdivision method considering extraordinary points)

  • 서흥석;조맹효
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 2003년도 봄 학술발표회 논문집
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    • pp.253-260
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    • 2003
  • In computer-aided geometric modeling(CAGD), subdivision surfaces are frequently employed to construct free-form surfaces. In the present study, Loop scheme and Catmull-Clark scheme are applied to generate smooth surfaces. To be consistent with the limit points of target surface, the initial sampling points are properly rearranged. The pointwise errors of curvature and position in the sequence of subdivision process are evaluated in both Loop scheme & Catmull-Clark subdivision scheme. In partcural, a general subdivision method in order to generate considering extraordinary points are implemented free from surface with arbitrary sampling point information.

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최적 경유점 선택 방법을 이용한 이동로봇의 반응적 주행 (Reactive navigation of mobile robots using optmal via-point selection method)

  • 김경훈;조형석
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1997년도 한국자동제어학술회의논문집; 한국전력공사 서울연수원; 17-18 Oct. 1997
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    • pp.227-230
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    • 1997
  • In this paper, robot navigation experiments with a new navigation algorithm are carried out in real environments. The authors already proposed a reactive navigation algorithm for mobile robots using optimal via-point selection method. At each sampling time, a number of via-point candidates is constructed with various candidates of heading angles and velocities. The robot detects surrounding obstacles, and the proposed algorithm utilizes fuzzy multi-attribute decision making in selecting the optimal via-point the robot would proceed at next step. Fuzzy decision making allows the robot to choose the most qualified via-point even when the two navigation goals-obstacle avoidance and target point reaching-conflict each other. The experimental result shows the successful navigation can be achieved with the proposed navigation algorithm for real environments.

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변량표본크기와 변량표본추출구간을 이용한$\bar{X}$관리도의 경제적 설계 (An Economic Design of $\bar{X}$ Control Charts with Variable Sample Size and Sampling Interval)

  • 김계완;윤덕균
    • 품질경영학회지
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    • 제28권3호
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    • pp.18-30
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    • 2000
  • Recent studies have shown that the $\bar{X}$ chart with variable sampling intervals(VSI) and the $\bar{X}$ chart with variable sample size(VSS) are much quicker than Shewhart $\bar{X}$ chart in detecting shiks in the process. Shewhart $\bar{X}$ chart has been beneficial to detect large shifts but it is hard to apply Shewhart $\bar{X}$ chart in detecting moderate shifts in the process mean. In this article the $\bar{X}$ chart using variable sample size(VSS) and variable sampling Intervals(VSI) has been proposed to supplement the weak point mentioned above. So the purpose of this paper is to consider finding the design parameters which minimize expected loss costs for unit process time and measure the performance of VSSI(variable sample size and sampling interval) $\bar{X}$ chart. It is important that assignable causes be detected to maintain the process controlled. This paper has been studied under the assumption that one cycle is from starting of the process to eliminating the assignable causes in the process. The other purpose of this article is to represent the expected loss costs in one cycle with three process parameters(sample size, sampling interval and control limits) function and find the three parameters.

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Comparison between Head Space Gas Sampling and Purge & Trap Sampling in Water Analysis

  • Nagayanagi, Yutaka;Nakagawa, Katsuhiro;Saito, Yoshihiro;Kim, Poongzag
    • 분석과학
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    • 제8권4호
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    • pp.739-744
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    • 1995
  • The two main methods to prepare water samples for analyzing volatile organic compounds(VOC's) were investigated. One is the purge and trap(PT) method and another is the head space(HS) sampling method. Both methods were effective to transfer the low boiling point components from the water sample onto the capillary column. The cryo-focusing at the top of the main capillary column was an effective way to obtain the sharpness of the chromatographic peaks but could be avoided when a semi-wide bore column was used. The recovery from the same amount of the sample was better in PT than in HS but a larger sample volume in HS method could compensate the lower efficiency. Therefore PT is suitable to the analysis of drinking water where the very low concentration must be determined. HS is suitable to waste water analysis because of the easiness of the operation. The repeatability was good and similar in both methods. For the contamination of the former sample, both methods were tough and could be used without any problems. The matrix effect which could change the equilibrium parameters in HS method was find negligible in many components. The actual samples such as tap water and river water were analyzed with both methods concerning 16 components regulated in Korea.

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