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Equivalent Conditions of Complete Convergence for Weighted Sums of Sequences of i.i.d.Random Variables under Sublinear Expectations
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作者 XU Mingzhou CHENG Kun 《应用概率统计》 北大核心 2025年第3期339-352,共14页
The complete convergence for weighted sums of sequences of independent,identically distributed random variables under sublinear expectation space is studied.By moment inequality and truncation methods,we establish the... The complete convergence for weighted sums of sequences of independent,identically distributed random variables under sublinear expectation space is studied.By moment inequality and truncation methods,we establish the equivalent conditions of complete convergence for weighted sums of sequences of independent,identically distributed random variables under sublinear expectation space.The results complement the corresponding results in probability space to those for sequences of independent,identically distributed random variables under sublinear expectation space. 展开更多
关键词 complete convergence weighted sums i.i.d.random variables sublinear expectation
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Kinematic calibration under the expectation maximization framework for exoskeletal inertial motion capture system
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作者 QIN Weiwei GUO Wenxin +2 位作者 HU Chen LIU Gang SONG Tainian 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第3期769-779,共11页
This study presents a kinematic calibration method for exoskeletal inertial motion capture (EI-MoCap) system with considering the random colored noise such as gyroscopic drift.In this method, the geometric parameters ... This study presents a kinematic calibration method for exoskeletal inertial motion capture (EI-MoCap) system with considering the random colored noise such as gyroscopic drift.In this method, the geometric parameters are calibrated by the traditional calibration method at first. Then, in order to calibrate the parameters affected by the random colored noise, the expectation maximization (EM) algorithm is introduced. Through the use of geometric parameters calibrated by the traditional calibration method, the iterations under the EM framework are decreased and the efficiency of the proposed method on embedded system is improved. The performance of the proposed kinematic calibration method is compared to the traditional calibration method. Furthermore, the feasibility of the proposed method is verified on the EI-MoCap system. The simulation and experiment demonstrate that the motion capture precision is significantly improved by 16.79%and 7.16%respectively in comparison to the traditional calibration method. 展开更多
关键词 human motion capture kinematic calibration EXOSKELETON gyroscopic drift expectation maximization(EM)
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Correcting the Expectation of Even Degree of Chicken Body Weight
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作者 WANGZhou-ji ZHANGLi-chao 《Journal of Northeast Agricultural University(English Edition)》 CAS 2000年第1期25-28,共4页
The even degree of chicken population could be estimated by the coefficient of variation or the percentage of the chicken whose body weights were not higher and lower than average body weight by 15% in the sampling po... The even degree of chicken population could be estimated by the coefficient of variation or the percentage of the chicken whose body weights were not higher and lower than average body weight by 15% in the sampling population.In fact,the two indexes were relative to each other.On the basis of analyzing the relationship between the two expectations,the expectations which had been worked out independently were corrected in this paper. 展开更多
关键词 CHICKEN even degree expectation CORRECTION
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Novel method for extraction of ship target with overlaps in SAR image via EM algorithm 被引量:1
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作者 CAO Rui WANG Yong 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第4期874-887,共14页
The quality of synthetic aperture radar(SAR)image degrades in the case of multiple imaging projection planes(IPPs)and multiple overlapping ship targets,and then the performance of target classification and recognition... The quality of synthetic aperture radar(SAR)image degrades in the case of multiple imaging projection planes(IPPs)and multiple overlapping ship targets,and then the performance of target classification and recognition can be influenced.For addressing this issue,a method for extracting ship targets with overlaps via the expectation maximization(EM)algorithm is pro-posed.First,the scatterers of ship targets are obtained via the target detection technique.Then,the EM algorithm is applied to extract the scatterers of a single ship target with a single IPP.Afterwards,a novel image amplitude estimation approach is pro-posed,with which the radar image of a single target with a sin-gle IPP can be generated.The proposed method can accom-plish IPP selection and targets separation in the image domain,which can improve the image quality and reserve the target information most possibly.Results of simulated and real mea-sured data demonstrate the effectiveness of the proposed method. 展开更多
关键词 expectation maximization(EM)algorithm image processing imaging projection plane(IPP) overlapping ship tar-get synthetic aperture radar(SAR)
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大规模网络的三角形模体社区发现模型 被引量:4
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作者 柴变芳 赵晓鹏 +1 位作者 贾彩燕 于剑 《南京大学学报(自然科学版)》 CAS CSCD 北大核心 2014年第4期466-473,共8页
研究表明将边表示的网络转换为三角形模体表示形式,可以有效解决基于模型社区发现方法由网络规模庞大带来的计算瓶颈问题.提出一个三角形模体社区发现模型MCDTM(a Model for Community Detection based on Triangular Motifs),其将网络... 研究表明将边表示的网络转换为三角形模体表示形式,可以有效解决基于模型社区发现方法由网络规模庞大带来的计算瓶颈问题.提出一个三角形模体社区发现模型MCDTM(a Model for Community Detection based on Triangular Motifs),其将网络表示为一系列三角形模体,利用categorical分布对各三角形模体的生成过程建模,用最大似然参数估计方法给出参数估计的推理过程,根据参数估计结果可得节点、边及三角形模体的社区隶属度.人工网络和实际网络上的实验证明MCDTM模型可快速准确地发现网络的潜在结构. 展开更多
关键词 三角形模体 大规模网络 重叠社区发现 EM(expectation Maximization)算法
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合肥市居住区居民户外活动与绿地环境的关系 被引量:1
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作者 赵霞 吴泽民 +1 位作者 李亚亮 苗璇璐 《中国城市林业》 2008年第1期27-30,共4页
通过调查合肥市3个居住区组团绿地空间中居民的活动和期望,分析居民活动与绿地空间的密切关系,探索提出与居民活动相适应的人性化绿地模式。结果表明:人们有很强烈的休闲期望,其中以休息、活动身体和呼吸新鲜空气为最主要。绿地空间的... 通过调查合肥市3个居住区组团绿地空间中居民的活动和期望,分析居民活动与绿地空间的密切关系,探索提出与居民活动相适应的人性化绿地模式。结果表明:人们有很强烈的休闲期望,其中以休息、活动身体和呼吸新鲜空气为最主要。绿地空间的活动也较为多样,以休息与散步为主,且居民活动与空间的性质、功能和设施有关。功能越多样,活动越丰富,满意度越高。同时,结合具体调查结果对绿地空间现状及存在的问题做出分析,在此基础上提出3个相应的绿地空间设计模式。 展开更多
关键词 RESIDENTIAL area CLUSTER green LAND ACTIVITIES ACTIVITIES expectation design pattern
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一种多尺度无监督遥感图像分割方法
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作者 郭小卫 官小平 《遥感信息》 CSCD 2006年第6期20-22,54,共4页
提出了一种多尺度无监督遥感图像分割方法。通过对多尺度图像数据在每个尺度上进行Gauss子集聚类,并将每个像素的邻域内的Gauss子集类别标记作为特征向量,利用Markov四叉树模型进行二次聚类,从而实现无监督图像分割。与其他基于多尺度Ma... 提出了一种多尺度无监督遥感图像分割方法。通过对多尺度图像数据在每个尺度上进行Gauss子集聚类,并将每个像素的邻域内的Gauss子集类别标记作为特征向量,利用Markov四叉树模型进行二次聚类,从而实现无监督图像分割。与其他基于多尺度Markov模型的无监督分割方法和传统动态聚类方法相比,该方法既无需假定每类的分布形式,又能较好地反映数据的概率结构。合成图像与SAR图像的实验结果表明,该方法的分割精度接近于有监督的H-MPM和H-SMAP方法。 展开更多
关键词 多尺度 四叉树 MPM(maximum POSTERIOR marginals) EM(expectation maximization)算法 无监督分割
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基于多特征的SAR图像多尺度无监督分割
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作者 郭小卫 官小平 《遥感信息》 CSCD 2006年第4期33-36,共4页
提出一种基于多特征的SAR图像多尺度无监督分割方法。该方法采用隐Markov树(hidden Markov tree,HMT)模型对SAR图像的灰度数据与标准差数据分别建模并分割,由两个分割结果提取SAR图像的结构性信息,并根据结构性信息,对灰度分割的后验概... 提出一种基于多特征的SAR图像多尺度无监督分割方法。该方法采用隐Markov树(hidden Markov tree,HMT)模型对SAR图像的灰度数据与标准差数据分别建模并分割,由两个分割结果提取SAR图像的结构性信息,并根据结构性信息,对灰度分割的后验概率进行平滑,最终的分割结果表明,该方法在很少损失结构性信息的基础上,能得到更光滑的分割结果。 展开更多
关键词 HMT(hidden Markov tree) SAR图像 RAYLEIGH分布 EM(expectation maximization)算法 ICE(iterative CONDITIONAL estimation)算法
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序言
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作者 殷浩文 《生态毒理学报》 CAS CSCD 北大核心 2017年第2期1-1,共1页
A model organism is a non-human species that is extensively studied to understand particular biological phenomena,with the expectation that discoveries made in the organism model will provide insight into the workings... A model organism is a non-human species that is extensively studied to understand particular biological phenomena,with the expectation that discoveries made in the organism model will provide insight into the workings of other organisms.模式生物是一类为了揭示特殊生物学现象而广泛采用的非人类种属,通过对模式生物物种进行的科学研究可以类推到同类或其他类别生物的某种具有普遍规律的生命现象。 展开更多
关键词 模式生物 生物学现象 INSIGHT 生物物种 expectation 生态毒理学 测试体系 化学品安全 阶段总结 环境管理
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一种高分辨率遥感图像目标自动提取方法 被引量:4
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作者 吴波 刘嘉 +1 位作者 王宏琦 吴一戎 《电子与信息学报》 EI CSCD 北大核心 2008年第11期2732-2736,共5页
该文提出一种高分辨率遥感图像目标自动提取方法,该方法首先使用分类器实现目标的快速检测,然后利用图像色彩模型和平滑性先验知识建立分割代价函数,并最小化此代价函数实现目标的精确提取,最后在后处理步骤中加入目标的形状先验知识,... 该文提出一种高分辨率遥感图像目标自动提取方法,该方法首先使用分类器实现目标的快速检测,然后利用图像色彩模型和平滑性先验知识建立分割代价函数,并最小化此代价函数实现目标的精确提取,最后在后处理步骤中加入目标的形状先验知识,进一步提高精度。以油罐提取为例进行了实验,结果证明了该方法的有效性和鲁棒性。 展开更多
关键词 Adaboost 有监督学习 高斯混合模型 EM(expectation Maximization)算法 目标提取
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基于非对称拉普拉斯分布的混合分位数回归参数估计 被引量:1
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作者 张发赶 何幼桦 《上海大学学报(自然科学版)》 CAS CSCD 北大核心 2021年第3期601-610,共10页
利用非对称拉普拉斯分布提出一种新的混合分位数回归模型.传统模型仅考虑位置参数,而所提出模型同时考虑了位置参数和尺度参数,并利用期望最大化(expectation maximization,EM)算法对模型参数进行估计.数值分析结果表明,参数估计的精度... 利用非对称拉普拉斯分布提出一种新的混合分位数回归模型.传统模型仅考虑位置参数,而所提出模型同时考虑了位置参数和尺度参数,并利用期望最大化(expectation maximization,EM)算法对模型参数进行估计.数值分析结果表明,参数估计的精度在各个分位数上均较为理想,并且估计精度随着样本量的增加而提高.最后运用所提出模型及其算法对城市房价数据进行分析. 展开更多
关键词 混合分位数回归 非对称拉普拉斯分布 期望最大化(expectation maximization EM)算法
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内核网络协议栈功能测试自动化的实现 被引量:2
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作者 刘渊 王开云 +1 位作者 范晓岚 姜建国 《计算机应用》 CSCD 北大核心 2005年第5期1052-1054,共3页
在研究手动测试过程的基础上,结合UML技术和Expect语言,提出了一种适用于操作系统内核级网络协议栈软件功能测试的自动化测试模型。在Linux操作系统上,用一个在一台计算机上即可开展的自动化测试示例验证了该模型及其相应技术手段的可行... 在研究手动测试过程的基础上,结合UML技术和Expect语言,提出了一种适用于操作系统内核级网络协议栈软件功能测试的自动化测试模型。在Linux操作系统上,用一个在一台计算机上即可开展的自动化测试示例验证了该模型及其相应技术手段的可行性,初步解决了测试的自动网络配置、自动数据驱动等问题,并在提高测试效率的同时降低了测试对硬件资源的需求。 展开更多
关键词 网络协议栈 自动化功能测试 UML Expect编程
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Real-time reliability evaluation based on damaged measurement degradation data 被引量:16
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作者 王小林 蒋平 +1 位作者 郭波 程志君 《Journal of Central South University》 SCIE EI CAS 2012年第11期3162-3169,共8页
A method was proposed to evaluate the real-time reliability for a single product based on damaged measurement degradation data.Most researches on degradation analysis often assumed that the measurement process did not... A method was proposed to evaluate the real-time reliability for a single product based on damaged measurement degradation data.Most researches on degradation analysis often assumed that the measurement process did not have any impact on the product's performance.However,in some cases,the measurement process may exert extra stress on products being measured.To obtain trustful results in such a situation,a new degradation model was derived.Then,by fusing the prior information of product and its own on-line degradation data,the real-time reliability was evaluated on the basis of Bayesian formula.To make the proposed method more practical,a procedure based on expectation maximization (EM) algorithm was presented to estimate the unknown parameters.Finally,the performance of the proposed method was illustrated by a simulation study.The results show that ignoring the influence of the damaged measurement process can lead to biased evaluation results,if the damaged measurement process is involved. 展开更多
关键词 degradation analysis damaged measurement real-time reliability expectation maximization algorithm
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资产相关结构对投资组合风险测度的影响分析 被引量:2
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作者 任仙玲 叶明确 张世英 《统计与决策》 CSSCI 北大核心 2008年第19期38-40,共3页
文章从分析金融资产收益率的统计特征入手,以GARCH模型为基础,用非对称幂分布描述组合资产中各金融资产收益率的边缘分布函数,在多种Copula函数情形下计算组合资产的风险值VaR及ES。结果表明:基于由多元Clayton Copula和多元Gumbel Cop... 文章从分析金融资产收益率的统计特征入手,以GARCH模型为基础,用非对称幂分布描述组合资产中各金融资产收益率的边缘分布函数,在多种Copula函数情形下计算组合资产的风险值VaR及ES。结果表明:基于由多元Clayton Copula和多元Gumbel Copula组成的混合Copula函数较好地刻画了多只股票的相关结构,而且ES比VaR能够较准确地估计组合资产的尾部风险。 展开更多
关键词 GAKCH模型 VALUE-AT-RISK 非对称幂分布:多元Copula函数 EXPECTED Shortfall
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网络协议栈软件的自动化测试研究与实现 被引量:1
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作者 刘渊 范晓岚 +1 位作者 王开云 姜建国 《计算机工程与应用》 CSCD 北大核心 2005年第15期120-122,182,共4页
在研究手动测试过程的基础上,结合UML(User-ModeLinux)技术和Expect语言,提出了一种适用于内核级网络协议栈软件的产品定型功能测试的自动化测试模型,并在Linux操作系统上,用一个在一台计算机上即可开展的自动化测试示例验证了该模型及... 在研究手动测试过程的基础上,结合UML(User-ModeLinux)技术和Expect语言,提出了一种适用于内核级网络协议栈软件的产品定型功能测试的自动化测试模型,并在Linux操作系统上,用一个在一台计算机上即可开展的自动化测试示例验证了该模型及其相应技术手段的可行性。该自动化测试模型可以在提高测试效率的同时降低测试对硬件资源的需求。 展开更多
关键词 网络协议栈 自动化测试 测试例 UML Expect编程
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Wigner-Ville distribution and cross Wigner-Ville distribution of noisy signals 被引量:4
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作者 Chen Guanghua Ma Shiwei Liu Ming Zhu Jingming Zeng Weimin 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第5期1053-1057,共5页
The Wigner-Ville distribution (WVD) and the cross Wigner-Ville distribution (XWVD) have been shown to be efficient in the estimation of instantaneous frequency (IF). But the statistical result of the IF estimati... The Wigner-Ville distribution (WVD) and the cross Wigner-Ville distribution (XWVD) have been shown to be efficient in the estimation of instantaneous frequency (IF). But the statistical result of the IF estimation from XWVD peak is much better than using WVD peak. The reason is given from a statistical point of view. Theoretical studies show that XWVD of the analyzed signal can be estimated from XWVD of the noise-contaminated signal. The estimation is unbiased, and the variance is equal to that of noise. In this case, WVD cannot be estimated from W-VD of the noise-contaminated signal. Therefore, higher SNR is required when WVD is used to analyze signals. 展开更多
关键词 Wigner-Ville distribution cross Wigner-Ville distribution instantaneous frequency expectation variance.
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A multi-target tracking algorithm based on Gaussian mixture model 被引量:4
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作者 SUN Lili CAO Yunhe +1 位作者 WU Wenhua LIU Yutao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2020年第3期482-487,共6页
Since the joint probabilistic data association(JPDA)algorithm results in calculation explosion with the increasing number of targets,a multi-target tracking algorithm based on Gaussian mixture model(GMM)clustering is ... Since the joint probabilistic data association(JPDA)algorithm results in calculation explosion with the increasing number of targets,a multi-target tracking algorithm based on Gaussian mixture model(GMM)clustering is proposed.The algorithm is used to cluster the measurements,and the association matrix between measurements and tracks is constructed by the posterior probability.Compared with the traditional data association algorithm,this algorithm has better tracking performance and less computational complexity.Simulation results demonstrate the effectiveness of the proposed algorithm. 展开更多
关键词 multiple-target tracking Gaussian mixture model(GMM) data association expectation maximization(EM)algorithm
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天然防腐剂--那他霉素(英文) 被引量:3
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作者 周莉 《肉类研究》 2008年第12期78-82,共5页
The article mainly introduced the character of antimicrobial Natamycin, the preservative mechanism, the application in meat products was reviewed and the development of Natamycin was proposed.
关键词 character of Natamycin SAFETY meat products expectation
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Effect of perceived control on human thermal comfort in heated environments 被引量:1
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作者 LIU Chang WANG Zhao-jun +3 位作者 SU Xiao-wen YANG Yu-xin ZHOU Fan-zhuo XU Run-pu 《Journal of Central South University》 SCIE EI CAS CSCD 2022年第7期2346-2356,共11页
To study the effects of perceived control on human thermal sensation and thermal comfort in heated environments,a psychological experiment was conducted.In total,24 subjects participated in an experiment.The experimen... To study the effects of perceived control on human thermal sensation and thermal comfort in heated environments,a psychological experiment was conducted.In total,24 subjects participated in an experiment.The experiment consisted of two cases in which the indoor temperature was set at 18℃ with different cold radiation temperatures.The experiment lasted for 120 min and was divided into three phases,adaptation,without perceived control and perceived control.In the second phase,the subjects were told in advance that the indoor temperature could not be adjusted.In the third phase,subjects were told that they could adjust the indoor temperature to meet their own thermal expectations,but the indoor temperature could not actually be changed.The results showed that the effect of perceived control on thermal sensation was related to the thermal expectation.For people with strong expectations for a neutral environment,perceived control improved their thermal sensation by satisfying their thermal expectations.For people with low thermal expectations,perceived control reduced their thermal tolerance to the environment,eventually leading to thermal discomfort.These new findings provide more supports for the importance of psychological effects and a reference for the personal control of heating temperatures. 展开更多
关键词 perceived control thermal expectation thermal sensation thermal comfort heating temperature
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Improved H-infinity channel estimator based on EM for MIMO-OFDM systems 被引量:1
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作者 Peng xu Jinkuan Wang Feng Qi 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2011年第4期572-578,共7页
H-infinity estimator is generally implemented in timevariant state-space models, but it leads to high complexity when the model is used for multiple input multiple output with orthogo- hal frequency division multiplex... H-infinity estimator is generally implemented in timevariant state-space models, but it leads to high complexity when the model is used for multiple input multiple output with orthogo- hal frequency division multiplexing (MIMO-OFDM) systems. Thus, an H-infinity estimator over time-invariant system models is pro- posed, which modifies the Krein space accordingly. In order to avoid the large matrix inversion and multiplication required in each OFDM symbol from different transmit antennas, expectation maximization (EM) is developed to reduce the high computational load. Joint estimation over multiple OFDM symbols is used to resist the high pilot overhead generated by the increasing number of transmit antennas. Finally, the performance of the proposed estimator is enhanced via an angle-domain process. Through performance analysis and simulation experiments, it is indicated that the pro- posed algorithm has a better mean square error (MSE) and bit error rate (BER) performance than the optimal least square (LS) estimator. Joint estimation over multiple OFDM symbols can not only reduce the pilot overhead but also promote the channel performance. What is more, an obvious improvement can be obtained by using the angle-domain filter. 展开更多
关键词 multiple input multiple output (MIMO) orthogonalfrequency division multiplexing (OFDM) channel estimation H-INFINITY expectation maximization (EM) angle domain.
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