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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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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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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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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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SV-t模型下人民币汇率VaR和ES的动态度量与分析
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作者 陈丽娟 《商业时代》 北大核心 2013年第12期65-67,共3页
人民币汇率的风险度量是汇率风险管理的关键环节。本文首先用SV-t模型对人民币对美元、日元及欧元汇率收益的波动率进行分析,在此基础上分别运用VaR和ES方法对其风险进行动态的度量与分析比较。结果表明:SV-t模型能够刻画出人民币汇率... 人民币汇率的风险度量是汇率风险管理的关键环节。本文首先用SV-t模型对人民币对美元、日元及欧元汇率收益的波动率进行分析,在此基础上分别运用VaR和ES方法对其风险进行动态的度量与分析比较。结果表明:SV-t模型能够刻画出人民币汇率收益率序列的波动特征;人民币对美元的VaR基本反映出其最大可能的损失;人民币对日元及欧元的Va R则低估了实际的风险水平,相应的ES虽保守却比较准确地估计出尾部风险。文章最后也对中国汇率市场的风险管理及风险监管提出了一些政策建议。 展开更多
关键词 人民币汇率 SV—t模型 学生t分布 Value—at—Risk expected Shortfall
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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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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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Statistical analysis of generalized exponential distribution under progressive censoring with binomial removals 被引量:11
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作者 Weian Yan Yimin Shi +1 位作者 Baowei Song Zhaoyong Mao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2011年第4期707-714,共8页
The estimation of generalized exponential distribution based on progressive censoring with binomial removals is presented, where the number of units removed at each failure time follows a binomial distribution. Maximu... The estimation of generalized exponential distribution based on progressive censoring with binomial removals is presented, where the number of units removed at each failure time follows a binomial distribution. Maximum likelihood estimators of the parameters and their confidence intervals are derived. The expected time required to complete the life test under this censoring scheme is investigated. Finally, the numerical examples are given to illustrate some theoretical results by means of Monte-Carlo simulation. 展开更多
关键词 binomial removal progressive censoring maximumlikelihood estimator expected experiment time generalized exponential distribution.
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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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批判与企盼:基于生命价值取向的高校道德教育 被引量:9
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作者 张世爱 《河南师范大学学报(哲学社会科学版)》 CSSCI 北大核心 2010年第1期243-245,共3页
目前高校德育存在着追求极端的道德理想主义,脱离"真实"的道德需求,追求绝对的客观知识,脱离学生的"本真"生活,规训和控制生命个体,压抑学生的自由发展,以道德认知为评价标准,影响学生主体人格发展等诸种弊端。通... 目前高校德育存在着追求极端的道德理想主义,脱离"真实"的道德需求,追求绝对的客观知识,脱离学生的"本真"生活,规训和控制生命个体,压抑学生的自由发展,以道德认知为评价标准,影响学生主体人格发展等诸种弊端。通过对这种现状的批判与反思,来透视高校德育中生命意识的遮蔽与缺失。在明乎困境的基础上,呼唤高校德育回归生活、回归自我、回归道德教育的本质,实现高校德育对生命价值的追求。 展开更多
关键词 生命 高校德育 批判 企盼
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突发事件下个体抢购物品现象的经济学分析 被引量:12
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作者 孙多勇 《经济与管理》 2006年第11期28-31,共4页
利用前景理论建立突发事件下信息对个体心理预期影响的理论模型,可对危机中的“抢购”行为进行理论分析。结果表明:危机事件下的“抢购”行为直接与人们的心理预期有关;私人信息会影响个体心理预期并产生过度反应;尽早公开信息有利于遏... 利用前景理论建立突发事件下信息对个体心理预期影响的理论模型,可对危机中的“抢购”行为进行理论分析。结果表明:危机事件下的“抢购”行为直接与人们的心理预期有关;私人信息会影响个体心理预期并产生过度反应;尽早公开信息有利于遏制私人信息影响;信息对个体风险感知的影响取决于个体接受信息的状态。 展开更多
关键词 前景理论 心理预期 行为决策 突发事件 经济学分析 “抢购”行为 信息公开 政府
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Performance-based seismic financial risk assessment of reinforced concrete frame structures 被引量:5
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作者 吴巧云 朱宏平 樊剑 《Journal of Central South University》 SCIE EI CAS 2012年第5期1425-1436,共12页
Engineering facilities subjected to natural hazards(such as winds and earthquakes) will result in risk when any designed system(i.e.capacity) will not be able to meet the performance required(i.e.demand).Risk might be... Engineering facilities subjected to natural hazards(such as winds and earthquakes) will result in risk when any designed system(i.e.capacity) will not be able to meet the performance required(i.e.demand).Risk might be expressed either as a likelihood of damage or potential financial loss.Engineers tend to make use of the former(i.e.damage).Nevertheless,other non-technical stakeholders cannot get useful information from damage.However,if financial risk is expressed on the basis of probable monetary loss,it will be easily understood by all.Therefore,it is necessary to develop methodologies which communicate the system capacity and demand to financial risk,Incremental dynamic analysis(IDA) was applied in a performance-based earthquake engineering context to do hazard analysis,structural analysis,damage analysis and loss analysis of a reinforced concrete(RC) frame structure.And the financial implications of risk were expressed by expected annual loss(EAL).The quantitative risk analysis proposed is applicable to any engineering facilities and any natural hazards.It is shown that the results from the IDA can be used to assess the overall financial risk exposure to earthquake hazard for a given constructed facility.The computational IDA-EAL method will enable engineers to take into account the long-term financial implications in addition to the construction cost.Consequently,it will help stakeholders make decisions. 展开更多
关键词 performance-based earthquake engineering (PBEE) incremental dynamic analysis (IDA) seismic risk analysis expected annual loss (EAL) seismic financial risk
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A statistical inference for generalized Rayleigh model under Type-Ⅱ progressive censoring with binomial removals 被引量:2
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作者 REN Junru GUI Wenhao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2020年第1期206-223,共18页
This paper considers the parameters and reliability characteristics estimation problem of the generalized Rayleigh distribution under progressively Type-Ⅱ censoring with random removals,that is,the number of units re... This paper considers the parameters and reliability characteristics estimation problem of the generalized Rayleigh distribution under progressively Type-Ⅱ censoring with random removals,that is,the number of units removed at each failure time follows the binomial distribution.The maximum likelihood estimation and the Bayesian estimation are derived.In the meanwhile,through a great quantity of Monte Carlo simulation experiments we have studied different hyperparameters as well as symmetric and asymmetric loss functions in the Bayesian estimation procedure.A real industrial case is presented to justify and illustrate the proposed methods.We also investigate the expected experimentation time and discuss the influence of the parameters on the termination point to complete the censoring test. 展开更多
关键词 Type-Ⅱprogressive censoring with random removals generalized Rayleigh distribution reliability characteristic maximum likelihood estimation Markov chain Monte Carlo method expected experimentation time
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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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Optimization of post-warranty sequential inspection for second-hand products 被引量:1
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作者 Dae-Kyung Kim Jae-Hak Lim Dong Ho Park 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2017年第4期793-800,共8页
This paper considers an optimal sequential inspection schedule for a second-hand product after that the free nonrenewable warranty is expired. The length of warranty is prespecified and during the warranty period, the... This paper considers an optimal sequential inspection schedule for a second-hand product after that the free nonrenewable warranty is expired. The length of warranty is prespecified and during the warranty period, the product is minimally repaired by the dealer when it fails. Following the expiration of the non-renewing warranty, the product is inspected and upgraded sequentially a fixed number of times at the expenses of the customer.At each inspection, the failure rate of the product is reduced proportionally so that the product is upgraded. The product is assumed to deteriorate as it ages and the replacement of the product occurs when a fixed number of inspections are rendered. In addition,the intervals between two successive inspections are assumed to decrease monotonically. The main objective of this paper is to determine the optimal improvement level to upgrade the product at each inspection so that the expected maintenance cost during the life cycle of the product is minimized from the perspective of the customer. Under the given cost structures, we derive an explicit formula to obtain the expected maintenance cost incurred during the life cycle of the product and discuss the method to find the optimal level of the improvement analytically in case the failure times follow the Weibull distribution. Numerical results are analyzed to observe the impact of relevant parameters on the optimal solution. 展开更多
关键词 second-hand product sequential inspection upgrade action life cycle of the product expected maintenance cost free non-renewable warranty
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E-Bayesian estimation for competing risk model under progressively hybrid censoring 被引量:3
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作者 Min Wu Yimin Shi Yan Wang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2016年第4期936-944,共9页
This paper considers the Bayesian and expected Bayesian(E-Bayesian) estimations of the parameter and reliability function for competing risk model from Gompertz distribution under Type-I progressively hybrid censori... This paper considers the Bayesian and expected Bayesian(E-Bayesian) estimations of the parameter and reliability function for competing risk model from Gompertz distribution under Type-I progressively hybrid censoring scheme(PHCS). The estimations are obtained based on Gamma conjugate prior for the parameter under squared error(SE) and Linex loss functions. The simulation results are provided for the comparison purpose and one data set is analyzed. 展开更多
关键词 Bayesian estimation expected Bayesian(E-Bayesian) estimation Gompertz distribution Type-I progressively hybrid censoring
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New approach for uncertain random multi-objective programming problems based on C_(ESD) criterion 被引量:1
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作者 SUN Yun WANG Ying +2 位作者 MENG Xiangfei FU Chaoqi LUO Chengkun 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2021年第3期619-630,共12页
To overcome the defects that the traditional ap-proach for multi-objective programming under uncertain ran-dom environment(URMOP)neglects the randomness and uncer-tainty of the problem and the volatility of the result... To overcome the defects that the traditional ap-proach for multi-objective programming under uncertain ran-dom environment(URMOP)neglects the randomness and uncer-tainty of the problem and the volatility of the results,a new ap-proach is proposed based on expected value-standard devi-ation value criterion(C_(ESD) criterion).Firstly,the effective solution to the URMOP problem is defined;then,by applying sequence relationship between the uncertain random variables,the UR-MOP problem is transformed into a single-objective program-ming(SOP)under uncertain random environment(URSOP),which are transformed into a deterministic counterpart based on the C_(ESD) criterion.Then the validity of the new approach is proved that the optimal solution to the SOP problem is also effi-cient for the URMOP problem;finally,a numerical example and a case application are presented to show the effectiveness of the new approach. 展开更多
关键词 chance theory independent-uncertain random multi-objective programming expected value-standard derivation value criterion(C_(ESD)criterion)
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网络异常IP自动截断设计与实现
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作者 黄伟强 聂瑞华 《华南师范大学学报(自然科学版)》 CAS 2008年第3期41-44,共4页
介绍了基于Expect语言对网络异常IP自动截断设计与实现,把sFlow流量监控技术结合起来,利用sFlow流量分析发现网络异常的IP地址,使用Expect语言模拟仿真Telnet的方式,传送ACL控制命令至网络异常IP连接相应的网络设备,从而实现对网络异常I... 介绍了基于Expect语言对网络异常IP自动截断设计与实现,把sFlow流量监控技术结合起来,利用sFlow流量分析发现网络异常的IP地址,使用Expect语言模拟仿真Telnet的方式,传送ACL控制命令至网络异常IP连接相应的网络设备,从而实现对网络异常IP进行自动截断处理的目的.网络异常IP自动截断设计与实现增强了网络对异常行为的控制,提高了网络正常运行的稳定性,减少了网络管理的工作量. 展开更多
关键词 SFLOW EXPECT TCL TELNET ACL
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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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