• Title/Summary/Keyword: efficient estimation

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An Efficient Thermal Stress Estimation Using Block Adaptive Filtering

  • Tai, Ming-Lang
    • 한국정보디스플레이학회:학술대회논문집
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    • 2009.10a
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    • pp.1269-1271
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    • 2009
  • We had proposed fast thermal stress estimation methodology for the components on system board when the system is stationary within specific ambient air temperature. Now, we will propose one efficient thermal stress estimation methodology, block adaptive filtering methodology, for the FPD electronic system board which is enclosed by mechanical cover.

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An Efficient Multi-level Successive Elimination Algorithm using the Locality in Block (동영상의 블록내 지역성을 이용하는 효율적인 다단계 연속 제거알고리즘)

  • Jung, Soo Mok
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.5 no.4
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    • pp.179-187
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    • 2009
  • In this paper, an efficient multi-level successive elimination algorithm using the locality in block was proposed for motion estimation. If SAD(sum of absolute difference) is calculated from large absolute difference values to small absolute difference values, SAD is increased rapidly. So, partial distortion elimination in SAD calculation can be done very early. Hence, the computations of SAD calculation can be reduced. In this paper, an efficient algorithm to calculate SAD from large absolute difference values to small absolute difference values by using the locality in block. Experimental results show that the proposed algorithm is an efficient algorithm with 100% motion estimation accuracy for the motion estimation of motion vectors.

A study on robust regression estimators in heteroscedastic error models

  • Son, Nayeong;Kim, Mijeong
    • Journal of the Korean Data and Information Science Society
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    • v.28 no.5
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    • pp.1191-1204
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    • 2017
  • Weighted least squares (WLS) estimation is often easily used for the data with heteroscedastic errors because it is intuitive and computationally inexpensive. However, WLS estimator is less robust to a few outliers and sometimes it may be inefficient. In order to overcome robustness problems, Box-Cox transformation, Huber's M estimation, bisquare estimation, and Yohai's MM estimation have been proposed. Also, more efficient estimations than WLS have been suggested such as Bayesian methods (Cepeda and Achcar, 2009) and semiparametric methods (Kim and Ma, 2012) in heteroscedastic error models. Recently, Çelik (2015) proposed the weight methods applicable to the heteroscedasticity patterns including butterfly-distributed residuals and megaphone-shaped residuals. In this paper, we review heteroscedastic regression estimators related to robust or efficient estimation and describe their properties. Also, we analyze cost data of U.S. Electricity Producers in 1955 using the methods discussed in the paper.

Efficient motion estimation and compensation methods for scalable video coding using 3D wavelet transform (3차원 웨이블릿 기반의 스케일러블 비디오 부호화를 위한 효과적인 움직임 예측 및 보상 방법)

  • 김종호;이준재;정제창
    • Proceedings of the IEEK Conference
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    • 2003.11a
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    • pp.433-436
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    • 2003
  • In this paper, the efficient motion estimation and compensation method for 3 dimensional wavelet transform is proposed. Recently, since the compression performance and scalable functionality are provided by wavelet transform, many researches have been carried out for applying to the video compression. For the temporal filtering, motion estimation and compensation techniques are used, but the unconnected pixels, which are produced by motion compensation result into the degradation of coding performance and quality of the picture. For the efficient motion compensated temporal filtering by reducing the number of these unconnected pixels, we propose the variable block size motion estimation and compensation method. Also we propose a method that determines the block size using rate-distortion optimization technique according to the local characteristics of the frame. The simulation results show the improved performances than the MPEG-4 scalable coding methods and the 3 dimensional wavelet coding methods using fixed block size motion estimation and compensation.

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Some Properties of Sequential Point Estimation of the Mean

  • Choi, Ki-Heon
    • Journal of the Korean Data and Information Science Society
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    • v.16 no.3
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    • pp.657-663
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    • 2005
  • Under the minimum risk point estimation formulation of Robbins(1959), we consider the sequential point estimation problem for normal population $N({\theta},\;{\theta})$ with unknown parameter ${\theta}$. In the case of completely unknown ${\theta}$, Stein's(1945) two-stage procedure is known to enjoy the consistency property, but it is not even first-order efficient. In the case when ${\theta}>{\theta}_L\;where\;{\theta}_L(>0)$ is known, the revised two-stage procedure is shown to enjoy all the usual second-order properties.

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Efficient Search Algorithm for Fast Motion Estimation

  • Park, Dong-Min;Kwak, Tong-Ill;Hwang, Bo-Hyun;Yun, Jong-Ho;Choi, Myung-Ryul
    • 한국정보디스플레이학회:학술대회논문집
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    • 2008.10a
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    • pp.737-740
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    • 2008
  • Block-matching motion estimation plays an important role in video coding. In this paper, we propose an Efficient Search Algorithm for Fast Motion Estimation. The proposed algorithm detects motion variation for reducing computational complexity before determining motion vector. Experimental results show that the proposed algorithm has good performance than conventional algorithms through quantitative evaluation.

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Estimation of Spatial Dependence with GEE

  • Lee, Yoon-Dong;Choi, Hye-Mi
    • Proceedings of the Korean Statistical Society Conference
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    • 2003.05a
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    • pp.269-273
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    • 2003
  • We consider an efficient parametric estimation method of spatial dependence in weak stationary processes. Spatial dependence is modeled through variogram and correlogram. Most of parametric estimation methods of correlogram use two step method; nonparametric estimation and parametric integration. We bind these two steps into one step by using GEE method instead of least squares type optimization. Our one step method is more efficient statistically and gives a clear interpretation of related concepts used in traditional two step methods.

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An Efficient Frequency-Offset Estimation using Diversity in OFOM-based Wirelss Systems (무선 OFDM 시스템에서 다이버시티를 이용한 효율적인 주파수 옵셋 추정)

  • Kim, Joon-Young;Chang, Sek-Chin
    • Proceedings of the KIEE Conference
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    • 2006.04a
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    • pp.60-62
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    • 2006
  • This paper presents an efficient frequency offset (FO) estimation algorithm for the orthogonal frequency division multiplexing (OFDM) based wireless local area networks (WLANS). The packet preamble imformation is utilized on the high rate WLAN standards adopted by the IEEE 802.11a. We present FO estimation schemes using diversity. In the simulation results, we prove that the presented schemes can improve the estimation performance compared with the convolutional scheme.

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An Efficient Global Motion Estimation based on Robust Estimator

  • Joo, Jae-Hwan;Choe, Yoon-Sik
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 2009.01a
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    • pp.408-412
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    • 2009
  • In this paper, a new efficient algorithm for global motion estimation is proposed. This algorithm uses a previous 4-parameter model based global motion estimation algorithm and M-estimator for improving the accuracy and robustness of the estimate. The first algorithm uses the block based motion vector fields and which generates a coarse global motion parameters. And second algorithm is M-estimator technique for getting precise global motion parameters. This technique does not increase the computational complexity significantly, while providing good results in terms of estimation accuracy. In this work, an initial estimation for the global motion parameters is obtained using simple 4-parameter global motion estimation approach. The parameters are then refined using M-estimator technique. This combined algorithm shows significant reduction in mean compensation error and shows performance improvement over simple 4-parameter global motion estimation approach.

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