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基于混合高斯模型的新型目标检测系统 被引量:11
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作者 金广智 石林锁 +1 位作者 白向峰 滕明春 《计算机应用》 CSCD 北大核心 2011年第12期3360-3362,3365,共4页
针对传统混合高斯模型计算量过大及其在非平稳背景下存在的问题,提出一种新型运动目标检测系统。该系统引入模型等权重初始化策略,改善了视频检测初始阶段的效果;通过基于线性均差的模型匹配方法,减少了对方差的运算次数,有效减少了模... 针对传统混合高斯模型计算量过大及其在非平稳背景下存在的问题,提出一种新型运动目标检测系统。该系统引入模型等权重初始化策略,改善了视频检测初始阶段的效果;通过基于线性均差的模型匹配方法,减少了对方差的运算次数,有效减少了模型的计算量;加入干扰信息处理模块,以增强模型在复杂背景下的生存能力。经实验验证,新型系统准确检测出了视频初始阶段的多运动目标,可使进入场景后停留的目标快速融入背景,并能有效克服非平稳背景的扰动。实验结果表明该系统相比经典模型,准确性和鲁棒性均有明显改善。 展开更多
关键词 目标检测 混合高斯模型 线性均差 非平稳背景
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A High Linearity,13bit Pipelined CMOS ADC 被引量:1
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作者 李福乐 段静波 王志华 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第3期497-501,共5页
A 13bit,pipelined analog-to-digital converter (ADC) designed to achieve high linearity is described. The high linearity is realized by using the passive capacitor error-averaging technique to calibrate the capacitor... A 13bit,pipelined analog-to-digital converter (ADC) designed to achieve high linearity is described. The high linearity is realized by using the passive capacitor error-averaging technique to calibrate the capacitor mismatch error, a gain-boosting opamp to minimize the finite gain error and gain nonlinearity,a bootstrapping switch to reduce the switch on-resistor nonlinearity, and an anti-disturb design to reduce the noise from the digital supply. This ADC is implemented in 0.18μm CMOS technology and occupies a die area of 3.2mm^2 , including pads. Measured performance includes - 0.18/ 0.15LSB of differential nonlinearity, -0.35/0.5LSB of integral nonlinearity, 75.7dB of signal-to-noise plus distortion ratio (SNDR) and 90. 5 dBc of spurious-free dynamic range (SFDR) for 2.4MHz input at 2.5MS/s. At full speed conversion (5MS/s) and for the same 2.4MHz input, the measured SNDR and SFDR are 73.7dB and 83.9 dBc, respectively. The power dissipation including output pad drivers is 21mW at 2.5MS/s and 34mW at 5MS/s,both at 2.7V supply. 展开更多
关键词 analog-to-digital converter high linearity capacitor error-averaging GAIN-BOOSTING bootstrapping switch anti-disturb
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Efficient fundamental frequency transformation for voice conversion
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作者 宋鹏 金赟 +2 位作者 包永强 赵力 邹采荣 《Journal of Southeast University(English Edition)》 EI CAS 2012年第2期140-144,共5页
In order to improve the performance of voice conversion, the fundamental frequency (F0) transformation methods are investigated, and an efficient F0 transformation algorithm is proposed. First, unlike the traditiona... In order to improve the performance of voice conversion, the fundamental frequency (F0) transformation methods are investigated, and an efficient F0 transformation algorithm is proposed. First, unlike the traditional linear transformation methods, the relationships between F0s and spectral parameters are explored. In each component of the Gaussian mixture model (GMM), the F0s are predicted from the converted spectral parameters using the support vector regression (SVR) method. Then, in order to reduce the over- smoothing caused by the statistical average of the GMM, a mixed transformation method combining SVR with the traditional mean-variance linear (MVL) conversion is presented. Meanwhile, the adaptive median filter, prevalent in image processing, is adopted to solve the discontinuity problem caused by the frame-wise transformation. Objective and subjective experiments are carried out to evaluate the performance of the proposed method. The results demonstrate that the proposed method outperforms the traditional F0 transformation methods in terms of the similarity and the quality. 展开更多
关键词 F0 prediction support vector regression meanvariance linear conversion adaptive median filter
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LMMSE-based SAGE channel estimation and data detection joint algorithm for MIMO-OFDM system 被引量:1
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作者 申京 Wu Muqing 《High Technology Letters》 EI CAS 2012年第2期195-201,共7页
A new channel estimation and data detection joint algorithm is proposed for multi-input multi-output (MIMO) - orthogonal frequency division multiplexing (OFDM) system using linear minimum mean square error (LMMSE... A new channel estimation and data detection joint algorithm is proposed for multi-input multi-output (MIMO) - orthogonal frequency division multiplexing (OFDM) system using linear minimum mean square error (LMMSE)- based space-alternating generalized expectation-maximization (SAGE) algorithm. In the proposed algorithm, every sub-frame of the MIMO-OFDM system is divided into some OFDM sub-blocks and the LMMSE-based SAGE algorithm in each sub-block is used. At the head of each sub-flame, we insert training symbols which are used in the initial estimation at the beginning. Channel estimation of the previous sub-block is applied to the initial estimation in the current sub-block by the maximum-likelihood (ML) detection to update channel estimatjon and data detection by iteration until converge. Then all the sub-blocks can be finished in turn. Simulation results show that the proposed algorithm can improve the bit error rate (BER) performance. 展开更多
关键词 multi-input multi-output (MIMO) orthogonal frequency division multiplexing (OFDM) linear minimum mean square error (LMMSE) space-alternating generalized expectation-maximization (SAGE) ITERATION channel estimation data detection joint algorithm.
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Slope displacement prediction based on morphological filtering 被引量:4
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作者 李启月 许杰 +1 位作者 王卫华 范作鹏 《Journal of Central South University》 SCIE EI CAS 2013年第6期1724-1730,共7页
Combining mathematical morphology (MM),nonparametric and nonlinear model,a novel approach for predicting slope displacement was developed to improve the prediction accuracy.A parallel-composed morphological filter wit... Combining mathematical morphology (MM),nonparametric and nonlinear model,a novel approach for predicting slope displacement was developed to improve the prediction accuracy.A parallel-composed morphological filter with multiple structure elements was designed to process measured displacement time series with adaptive multi-scale decoupling.Whereafter,functional-coefficient auto regressive (FAR) models were established for the random subsequences.Meanwhile,the trend subsequence was processed by least squares support vector machine (LSSVM) algorithm.Finally,extrapolation results obtained were superposed to get the ultimate prediction result.Case study and comparative analysis demonstrate that the presented method can optimize training samples and show a good nonlinear predicting performance with low risk of choosing wrong algorithms.Mean absolute percentage error (MAPE) and root mean square error (RMSE) of the MM-FAR&LSSVM predicting results are as low as 1.670% and 0.172 mm,respectively,which means that the prediction accuracy are improved significantly. 展开更多
关键词 slope displacement prediction parallel-composed morphological filter functional-coefficient auto regressive predictionaccuracy
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A Quantitative Structure Property Relationship for Prediction of Flash Point of Alkanes Using Molecular Connectivity Indices 被引量:3
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作者 Morteza Atabati Reza Emamalizadeh 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第4期420-426,共7页
Many structure-property/activity studies use graph theoretical indices, which are based on the topological properties of a molecule viewed as a graph. Since topological indices can be derived directly from the molecul... Many structure-property/activity studies use graph theoretical indices, which are based on the topological properties of a molecule viewed as a graph. Since topological indices can be derived directly from the molecular structure without any experimental effort, they provide a simple and straightforward method for property prediction. In this work the flash point of alkanes was modeled by a set of molecular connectivity indices (Х), modified molecular connectivity indices ( ^mХ^v ) and valance molecular connectivity indices ( ^mХ^v ), with ^mХ^v calculated using the hydrogen perturbation. A stepwise Multiple Linear Regression (MLR) method was used to select the best indices. The predicted flash points are in good agreement with the experimental data, with the average absolute deviation 4.3 K. 展开更多
关键词 quantitative structure property relationship flash point molecular connectivity indices hydrogen perturbation ALKANE
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New sigma point filtering algorithms for nonlinear stochastic systems with correlated noises 被引量:2
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作者 王小旭 潘泉 +1 位作者 程咏梅 赵春晖 《Journal of Central South University》 SCIE EI CAS 2012年第4期1010-1020,共11页
New sigma point filtering algorithms, including the unscented Kalman filter (UKF) and the divided difference filter (DDF), are designed to solve the nonlinear filtering problem under the condition of correlated no... New sigma point filtering algorithms, including the unscented Kalman filter (UKF) and the divided difference filter (DDF), are designed to solve the nonlinear filtering problem under the condition of correlated noises. Based on the minimum mean square error estimation theory, the nonlinear optimal predictive and correction recursive formulas under the hypothesis that the input noise is correlated with the measurement noise are derived and can be described in a unified framework. Then, UKF and DDF with correlated noises are proposed on the basis of approximation of the posterior mean and covariance in the unified framework by using unscented transformation and second order Stirling's interpolation. The proposed UKF and DDF with correlated noises break through the limitation that input noise and measurement noise must be assumed to be uneorrelated in standard UKF and DDF. Two simulation examples show the effectiveness and feasibility of new algorithms for dealing with nonlinear filtering issue with correlated noises. 展开更多
关键词 nonlinear system correlated noise sigma point unscented Kalman filter divided difference filter
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Minimax Estimation Problem for Periodically Correlated Stochastic Processes
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作者 Iryna Dubovetska Mykhailo Moklyachuk 《Journal of Mathematics and System Science》 2013年第1期26-30,共5页
The problem of optimal linear estimation of the functional Aξ =10^∞a(t)ζ((t)dt depending on the unknown values of periodically correlated stochastic process ζ(t) from observations of this process for t 〈 0... The problem of optimal linear estimation of the functional Aξ =10^∞a(t)ζ((t)dt depending on the unknown values of periodically correlated stochastic process ζ(t) from observations of this process for t 〈 0 is considered. Formulas that determine the greatest value of mean square error and the minimax estimation for the functional are proposed for the given class of admissible processes. It is shown that one-sided moving average stationary sequence gives the greatest value of the mean square error. 展开更多
关键词 Periodically correlated process minimax estimate mean SOlUte error least favorable process.
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An Extension of the Dimension-Reduced Projection 4DVar
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作者 SHEN Si LIU Juan-Juan WANG Bin 《Atmospheric and Oceanic Science Letters》 CSCD 2014年第4期324-329,共6页
This paper extends the dimension-reduced projection four-dimensional variational assimilation method(DRP-4DVar) by adding a nonlinear correction process,thereby forming the DRP-4DVar with a nonlinear correction, which... This paper extends the dimension-reduced projection four-dimensional variational assimilation method(DRP-4DVar) by adding a nonlinear correction process,thereby forming the DRP-4DVar with a nonlinear correction, which shall hereafter be referred to as the NC-DRP-4DVar. A preliminary test is conducted using the Lorenz-96 model in one single-window experiment and several multiple-window experiments. The results of the single-window experiment show that compared with the adjoint-based traditional 4DVar, the final convergence of the cost function for the NC-DRP-4DVar is almost the same as that using the traditional 4DVar, but with much less computation. Furthermore, the 30-window assimilation experiments demonstrate that the NC-DRP-4DVar can alleviate the linearity approximation error and reduce the root mean square error significantly. 展开更多
关键词 data assimilation linear approximation nonlinear correction OSSE
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Cyclic beamforming using fractional Fourier transform domain cyclostationarity
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作者 Muhammad Ishtiaq Ahmad Liu Zhiwen Xu Yougen 《High Technology Letters》 EI CAS 2011年第1期57-63,共7页
A minimum mean-squared error (MSE) beamforming algorithm employing the optimum fractional Fourier transform (Opt-FrFT) domain second-order cyclostationarity is proposed. This method can efficiently filter out the ... A minimum mean-squared error (MSE) beamforming algorithm employing the optimum fractional Fourier transform (Opt-FrFT) domain second-order cyclostationarity is proposed. This method can efficiently filter out the compact desired chirp signal, with a consequence that the cyclically uncorrelated interferences and stationary (colored) Gaussian noise are greatly suppressed in the Opt- FrFT domain. This improves the MSE minimization cyclic beamformer by reducing effectively the Opt-FrFY domain signal-noise cross terms in the presence of finite data length de-correlation operation. Simulation results show that the new method works well under a wide range of signal-to-noise ratio (SNR) and signal-to-interference ratio (SIR). 展开更多
关键词 BEAMFORMING fractional Fourier transform chirp signal CYCLOSTATIONARITY
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Properties of A=7-9 Drip-Line Nuclei in RMF Theory
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作者 WANG Cheng-Bin DONG Tie-Kuang +1 位作者 REN Zhong-Zhou ZHU Zhi-Yuan 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第5期895-898,共4页
The relativistic mean-field (RMF) theory is used to calculate the properties of A =7-9 drip-line nuclei ^7Li, ^7;9Be, ^8;9B, and ^9C. Systematic deviations between experimental and theoretical binding energies are f... The relativistic mean-field (RMF) theory is used to calculate the properties of A =7-9 drip-line nuclei ^7Li, ^7;9Be, ^8;9B, and ^9C. Systematic deviations between experimental and theoretical binding energies are found. Possible reasons of these systematic deviations are discussed in terms of pairing energy. The root-mean-square (rms) radii of matter distributions for these nuclei agree with the experimental data quite well. The one-proton halo structure in ^8B is reproduced well, and the two-proton halo in ^9C is predicted. The calculations show that the RMF theory is valid in studying the properties of light drip-line nuclei. 展开更多
关键词 RMF method drip-line nuclei nuclear structure
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Joint Transceiver Design for OFDM Systems
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作者 Chen Rui Li Jiandong +1 位作者 Li Changle Liu Wei 《China Communications》 SCIE CSCD 2012年第2期43-51,共9页
Orthogonal Frequency Division Multiplexing(OFDM) is an effective technique to deal with a frequency selective channel since it can convert the channel into some flat fading subchannels.However,very different output SN... Orthogonal Frequency Division Multiplexing(OFDM) is an effective technique to deal with a frequency selective channel since it can convert the channel into some flat fading subchannels.However,very different output SNR values of the subchannels will lead to poor bit error performance when a linear equalizer and Equal Bit Allocation(EBA) are adopted in OFDM systems.So,we proposed three novel nonlinear Joint Transceiver(JT) schemes based on Zero-Forcing(ZF) criterion and Minimum Mean Square Error(MMSE) criterion respectively,which can transform all subchannels of an OFDM system into subchannels with identical channel gain.Thus,EBA is equivalent to the Optimum Bit Allocation(OBA) for these subchannels.Numerical analysis helps us to obtain the theoretical approximate BER values of the JT scheme.Simulation results verify the numerical analysis and confirm that the performance of our proposed JT scheme greatly outperforms the traditional linear equalizer with EBA at moderate and high SNR values. 展开更多
关键词 OFDM joint transceiver design VBLAST dirty paper coding
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Rapid prediction of floating and sinking components of raw coal
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作者 Wang Guanghui Kuang Yali Wang Zhangguo Ji Li Wang Ying 《International Journal of Mining Science and Technology》 SCIE EI 2012年第5期735-738,共4页
A model that rapidly predicts the density components of raw coal is described.It is based on a threegrade fast float/sink test.The recent comprehensive monthly floating and sinking data are used for comparison.The pre... A model that rapidly predicts the density components of raw coal is described.It is based on a threegrade fast float/sink test.The recent comprehensive monthly floating and sinking data are used for comparison.The predicted data are used to draw washability curves and to provide a rapid evaluation of the effect from heavy medium induced separation.Thirty-one production shifts worth of fast float/sink data and the corresponding quick ash data are used to verify the model.The results show a small error with an arithmetic average of 0.53 and an absolute average error of 1.50.This indicates that this model has high precision.The theoretical yield from the washability curves is 76.47% for the monthly comprehensive data and 81.31% using the model data.This is for a desired cleaned coal ash of 9%.The relative error between these two is 6.33%,which is small and indicates that the predicted data can be used to rapidly evaluate the separation effect of gravity separation equipment. 展开更多
关键词 Raw coal Floating and sinking components Fast floating and sinking data Predicting model
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A new group contribution-based method for estimation of flash point temperature of alkanes
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作者 戴益民 刘辉 +5 位作者 陈晓青 刘又年 李浔 朱志平 张跃飞 曹忠 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第1期30-36,共7页
Flash point is a primary property used to determine the fire and explosion hazards of a liquid. New group contribution-based models were presented for estimation of the flash point of alkanes by the use of multiple li... Flash point is a primary property used to determine the fire and explosion hazards of a liquid. New group contribution-based models were presented for estimation of the flash point of alkanes by the use of multiple linear regression(MLR)and artificial neural network(ANN). This simple linear model shows a low average relative deviation(AARD) of 2.8% for a data set including 50(40 for training set and 10 for validation set) flash points. Furthermore, the predictive ability of the model was evaluated using LOO cross validation. The results demonstrate ANN model is clearly superior both in fitness and in prediction performance.ANN model has only the average absolute deviation of 2.9 K and the average relative deviation of 0.72%. 展开更多
关键词 flash point alkane group contribution artificial neural network(ANN) quantitative structure-property relationship(QSPR)
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Further results on differentially 4-uniform permutations over F2^2m 被引量:4
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作者 ZHA ZhengBang HU Lei +1 位作者 SUN SiWei SHAN JinYong 《Science China Mathematics》 SCIE CSCD 2015年第7期1577-1588,共12页
We present several new constructions of differentially 4-uniform permutations over F22 mby modifying the values of the inverse function on some subsets of F22 m. The resulted differentially 4-uniform permutations have... We present several new constructions of differentially 4-uniform permutations over F22 mby modifying the values of the inverse function on some subsets of F22 m. The resulted differentially 4-uniform permutations have high nonlinearities and algebraic degrees, which provide more choices for the design of crytographic substitution boxes. 展开更多
关键词 PERMUTATION differentially 4-uniform function NONLINEARITY algebraic degree
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THE SUPERIORITIES OF BAYES LINEAR UNBIASED ESTIMATION IN PARTITIONED LINEAR MODEL 被引量:6
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作者 Weiping ZHANG Laisheng WEI Yu CHEN 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2011年第5期945-954,共10页
In this article, the Bayes linear unbiased estimation (BALUE) of parameters is derived for the partitioned linear model. The superiorities of the BALUE over ordinary least square estimator (LSE) are studied in ter... In this article, the Bayes linear unbiased estimation (BALUE) of parameters is derived for the partitioned linear model. The superiorities of the BALUE over ordinary least square estimator (LSE) are studied in terms of the Bayes mean square error matrix (BMSEM) criterion and Pitman closeness (PC) criterion. 展开更多
关键词 Bayes linear unbiased estimation Bayes mean square error matrix criterion least squareestimation partitioned linear model Pitman closeness criterion.
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Refining Soil Organic Matter Determination by Loss-on-Ignition 被引量:15
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作者 M.H.SALEHI O.HASHEMI BENI +2 位作者 H.BEIGI HARCHEGANI I.ESFANDIARPOUR BORUJENI H.R.MOTAGHIAN 《Pedosphere》 SCIE CAS CSCD 2011年第4期473-482,共10页
Wet oxidation procedure,i.e.,Walkley-Black (WB) method,is a routine,relatively accurate,and popular method for the determination of soil organic matter (SOM) but it is time-consuming,costly and also has a high potenti... Wet oxidation procedure,i.e.,Walkley-Black (WB) method,is a routine,relatively accurate,and popular method for the determination of soil organic matter (SOM) but it is time-consuming,costly and also has a high potential to cause environmental pollution because of disposal of chromium and strong acids used in this analysis.Therefore,loss-on-ignition (LOI) procedure,a simple and cheap method for SOM estimation,which also avoids chromic acid wastes,deserves more attention.The aims of this research were to study the statistical relationships between SOM determined with the LOI (SOMLOI) and WB (SOMWB) methods to compare the spatial variability of SOM in two major plains,Shahrekord and Koohrang plains,of Chaharmahal-va-Bakhtiari Province,Iran.Fifty surface soil samples (0-25 cm) were randomly collected in each plain to determine SOM using the WB method and the LOI procedure at 300,360,400,500 and 550 ℃ for 2 h.The samples covered wide ranges of soil texture and calcium carbonate equivalent (CCE).The general linear form of the regression equation was calculated to estimate SOM LOI from SOM obtained by the WB method for both overall samples and individual plains.Forty soil samples were also randomly selected to compare the SOM and CCE before and after ignition at each temperature.Overall accuracy of the continuous maps generated for the LOI and WB methods was considered to determine the accordance of two procedures.Results showed a significant positive linear relationship between SOM LOI and SOM WB.Coefficients of determination (R2) of the equations for individual plains were higher than that of the overall equation.Coefficients of determination and line slopes decreased and root mean square error (RMSE) increased with increasing ignition temperature,which may be due to the mineral structural water loss and destruction of carbonates at higher temperatures.A temperature around 360 ℃ was identified as optimum as it burnt most organic carbon,destroyed less inorganic carbon,caused less clay structural water loss,and used less electrical energy.Although the trends of SOM in the kriged maps by the two procedures accorded well,low overall accuracy was observed for the maps obtained by the two methods.While not suitable for determination where high accuracy is required,determination of organic carbon through LOI is likely suitable for exploratory soil surveys where rough estimation of organic matter is required. 展开更多
关键词 calcium carbonate equivalent ignition temperature kriged maps spatial variability wet oxidation
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Randomly Weighted LAD-Estimation for Partially Linear Errors-in-Variables Models
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作者 Xiaohan YANG Rong JIANG Weimin QIAN 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2015年第4期561-578,共18页
The authors consider the partially linear model relating a response Y to predictors (x, T) with a mean function x^Tβ0 + g(T) when the x's are measured with an additive error. The estimators of parameter β0 are... The authors consider the partially linear model relating a response Y to predictors (x, T) with a mean function x^Tβ0 + g(T) when the x's are measured with an additive error. The estimators of parameter β0 are derived by using the nearest neighbor-generalized randomly weighted least absolute deviation (LAD for short) method. The resulting estimator of the unknown vector 30 is shown to be consistent and asymptotically normal. In addition, the results facilitate the construction of confidence regions and the hypothesis testing for the unknown parameters. Extensive simulations are reported, showing that the proposed method works well in practical settings. The proposed methods are also applied to a data set from the study of an AIDS clinical trial group. 展开更多
关键词 Partially linear errors-in-variables LAD-estimation Randomly weighted method Linear hypothesis Randomly weighted LAD-test
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Linear Bayes Estimators Applied to the Inverse Gaussian Lifetime Model 被引量:1
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作者 WANG Lichun PETTIT Lawrence 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2016年第6期1683-1692,共10页
For the two-parameter inverse Gaussian distribution denoted by IG(μ,A), the authors employ a linear Bayes procedure to estimate the parameters μ and A. The superiority of the proposed linear Bayes estimator (LBE... For the two-parameter inverse Gaussian distribution denoted by IG(μ,A), the authors employ a linear Bayes procedure to estimate the parameters μ and A. The superiority of the proposed linear Bayes estimator (LBE) over both the classical UMVUE and the maximum likelihood estimator (MLE) is established in terms of the mean squared error matrix (MSEM) criterion. Compared with the usual Bayes estimator, which is obtained by an MCMC method, the proposed LBE is simple and easy to use. Some numerical results are presented to verify that the LBE performs well. 展开更多
关键词 Linear Bayes method MCMC method mean squared error matrix (MSEM) quadraticloss.
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PERFORMANCE ANALYSIS OF OPTIMAL CHANNEL ESTIMATION AND MULTIUSER DETECTION IN A RANDOMLY-SPREAD CDMA CHANNEL
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作者 Keigo TAKEUCHI Mikko VEHKAPER +1 位作者 Toshiyuki TANAKA Ralf R.MLLER 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2010年第1期22-34,共13页
This paper analyzes performance of optimal channel estimation and multiuser detection(MUD) in a block-fading code-division multiple-access (CDMA) channel on the assumptions of randomspreading and large-system limit,by... This paper analyzes performance of optimal channel estimation and multiuser detection(MUD) in a block-fading code-division multiple-access (CDMA) channel on the assumptions of randomspreading and large-system limit,by using the replica method developed in statistical mechanics.The authors find that the asymptotic spectral efficiency of the linear minimum mean-squared error(LMMSE) MUD which was proposed and analyzed by Evans and Tse in 2000 is indistinguishable fromthat of the optimal MUD for small system loads.Our results imply that performance of MUD scarcelyimproves even if one spends more computational cost than that of the LMMSE MUD,i.e.,at most thecube of the number of users,on the above-described conditions. 展开更多
关键词 Channel estimation code-division multiple-access (CDMA) systems multiuser detection replica method spectral efficiency.
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