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A correlative classifiers approach based on particle filter and sample set for tracking occluded target 被引量:6
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作者 LI Kang HE Fa-zhi +1 位作者 YU Hai-ping CHEN Xiao 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2017年第3期294-312,共19页
Target tracking is one of the most important issues in computer vision and has been applied in many fields of science, engineering and industry. Because of the occlusion during tracking, typical approaches with single... Target tracking is one of the most important issues in computer vision and has been applied in many fields of science, engineering and industry. Because of the occlusion during tracking, typical approaches with single classifier learn much of occluding background information which results in the decrease of tracking performance, and eventually lead to the failure of the tracking algorithm. This paper presents a new correlative classifiers approach to address the above problem. Our idea is to derive a group of correlative classifiers based on sample set method. Then we propose strategy to establish the classifiers and to query the suitable classifiers for the next frame tracking. In order to deal with nonlinear problem, particle filter is adopted and integrated with sample set method. For choosing the target from candidate particles, we define a similarity measurement between particles and sample set. The proposed sample set method includes the following steps. First, we cropped positive samples set around the target and negative samples set far away from the target. Second, we extracted average Haar-like feature from these samples and calculate their statistical characteristic which represents the target model. Third, we define the similarity measurement based on the statistical characteristic of these two sets to judge the similarity between candidate particles and target model. Finally, we choose the largest similarity score particle as the target in the new frame. A number of experiments show the robustness and efficiency of the proposed approach when compared with other state-of-the-art trackers. 展开更多
关键词 visual tracking sample set method online learning particle filter
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Prevention the fever of NHTR reactions using blood transfusion set with leucocyte removal filter 被引量:1
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《中国输血杂志》 CAS CSCD 2001年第S1期335-,共1页
关键词 Prevention the fever of NHTR reactions using blood transfusion set with leucocyte removal filter
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针对动态集的矩阵型Bloom filter表示与查找 被引量:4
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作者 肖明忠 王佳聪 闵博楠 《计算机应用研究》 CSCD 北大核心 2008年第7期2001-2003,2022,共4页
提出一种针对动态集合的矩阵型Bloom filter表示与查找法(matrix Bloom filter,MBF),它使用一个s×m位矩阵对数据集合进行哈希表示与查找,较同类算法SBF和DBF,能继承Bloom filter算法常数查找开销的基本精髓。
关键词 BLOOM过滤器 动态集 拆分型Bloomfilter 动态性Bloomfilter 矩阵型Bloomfilter
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基于Rough Set理论的实时个人邮件过滤系统的研究 被引量:1
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作者 于洪 杨大春 吴中福 《计算机工程与应用》 CSCD 北大核心 2004年第16期18-19,49,共3页
电子邮件过滤是网络信息安全研究的热点。RoughSet理论是一种处理含糊和不精确性问题的一种新型数学工具,得到了广泛应用。文章结合RoughSet理论的数据分析方法针对实时个人用户电子邮件过滤系统进行了研究。实验结果表明,该方法是有效的。
关键词 个人电子邮件过滤 ROUGH set理论 数据分析
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Rough Set中正区域的若干性质 被引量:4
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作者 叶东毅 陈昭炯 《福州大学学报(自然科学版)》 CAS CSCD 2002年第5期521-523,共3页
分析了不同正区域之间的关系 ,在此基础上给出有关正区域计算的若干新的性质 ,如记录过滤性质、替换计算性质和分解计算性质等 .利用这些性质可以降低正区域动态计算的计算量 .
关键词 ROUGH set 粗糙集理论 正区域 记录过滤性质 替换计算性质 分解计算性质 计算量
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基于Bloom filter的远程对称差规模估算法
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作者 田小梅 胡灿 龚静 《计算技术与自动化》 2013年第4期75-79,共5页
在内容分发网络、闲谈协议、移动数据同步等分布式系统中,远程主机上集合对称差规模的估算准确程度,直接影响基于CPISync算法的集合调和方法的消息交换轮数以及调和时间。对称差规模的估算误差越低,则集合调和的速度越快。本文提出基于... 在内容分发网络、闲谈协议、移动数据同步等分布式系统中,远程主机上集合对称差规模的估算准确程度,直接影响基于CPISync算法的集合调和方法的消息交换轮数以及调和时间。对称差规模的估算误差越低,则集合调和的速度越快。本文提出基于布鲁姆过滤器的准交集查询法,该算法可显著降低对称差规模的估算误差,提高调和算法的效率。 展开更多
关键词 移动计算 布鲁姆过滤器 集合调和 数据同步
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Rough Set在垃圾邮件过滤技术中的应用
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作者 张宁丹 《湘南学院学报》 2007年第2期69-72,共4页
垃圾邮件是Internet上面临急待解决的问题.Rough集理论是处理模糊和不精确数据的新型工具,能提供描述正常模型的最小预测规则集.重点阐述了Rough set在垃圾邮件过滤中的应用,并对大量数据进行了实验对比,试验验证了Rough set在垃圾邮件... 垃圾邮件是Internet上面临急待解决的问题.Rough集理论是处理模糊和不精确数据的新型工具,能提供描述正常模型的最小预测规则集.重点阐述了Rough set在垃圾邮件过滤中的应用,并对大量数据进行了实验对比,试验验证了Rough set在垃圾邮件过滤技术上的可行性和可靠性. 展开更多
关键词 垃圾邮件 ROUGH set 过滤技术 网络应用
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一种基于SET/CMOS电路的二阶低通滤波器
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作者 陈学军 黄聚义 《青岛大学学报(自然科学版)》 CAS 2004年第4期57-60,共4页
在研究单电子晶体管(single electron transistor,SET)Ⅰ—Ⅴ特性的基础上,依据分区处理法,设计了一个SET积分器电路,并采用级联方法实现了一个SET/CMOS二阶低通滤波器。仿真结果表明,该滤波器的幅频特性增益比采用其它方法描述SET... 在研究单电子晶体管(single electron transistor,SET)Ⅰ—Ⅴ特性的基础上,依据分区处理法,设计了一个SET积分器电路,并采用级联方法实现了一个SET/CMOS二阶低通滤波器。仿真结果表明,该滤波器的幅频特性增益比采用其它方法描述SET Ⅰ—Ⅴ特性所构成的滤波器的幅频特性增益高出1倍多。 展开更多
关键词 单电子晶体管 set I-V特性 积分器 低通滤波器 传输特性
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可数-定向集与ω^(*)-well-filtered空间 被引量:1
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作者 张曼怡 徐晓泉 《模糊系统与数学》 北大核心 2023年第6期90-99,共10页
本文利用可数-定向集,引入了ω^(*)-Rudin空间和ω^(*)-well-filtered决定空间的概念,讨论了ω^(*)-well-filtered空间及相关空间的收缩性、乘积性、反射性等基本性质,给出了ω^(*)-well-filtered性的等价刻画,得到了如下主要结果:(1)ω... 本文利用可数-定向集,引入了ω^(*)-Rudin空间和ω^(*)-well-filtered决定空间的概念,讨论了ω^(*)-well-filtered空间及相关空间的收缩性、乘积性、反射性等基本性质,给出了ω^(*)-well-filtered性的等价刻画,得到了如下主要结果:(1)ω^(*)-Rudin空间的连续收缩核仍然是ω^(*)-Rudin空间;(2)ω^(*)-well-filtered决定空间的连续收缩核仍然是ω^(*)-well-filtered决定空间;(3)设{X_(i):1≤i≤n}是有限个T_(0)空间,则n∏i=1X_(i)是ω^(*)-well-filtered决定空间当且仅当每个因子空间X_(i)是ω^(*)-well-filtered决定空间(i=1,2,…,n);(4)ω^(*)-well-filtered空间的连续收缩核是ω^(*)-well-filtered空间;(5)设{X_(i):i∈I}是一族T_(0)空间,则∏i∈IX_(i)是ω^(*)-well-filtered空间当且仅当每个因子空间X_(i)是ω^(*)-well-filtered空间(i∈I);(6)ω^(*)-well-filtered空间范畴是T_(0)空间范畴的满子反射范畴,并给出了T_(0)空间ω^(*)-well-filtered反射的具体构造。 展开更多
关键词 可数-定向集 ω^(*)-well-filtered空间 ω^(*)-d-空间 Smyth幂空间 反射
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Logical Properties of Lattice Filter of Lattice Implication Algebra 被引量:4
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作者 赖家俊 徐扬 宋振明 《Journal of Southwest Jiaotong University(English Edition)》 2007年第4期353-356,共4页
Some new properties of lattice filters are presented based on the order-preserving mapping and lattice homomorphism, and two necessary and sufficient conditions for lattice filters under the chain type are given. Then... Some new properties of lattice filters are presented based on the order-preserving mapping and lattice homomorphism, and two necessary and sufficient conditions for lattice filters under the chain type are given. Then, the relations between lattice filter and lattice implication algebras (LIAs), i. e., the relations between lattice filter and LIA-filters, and the related properties are investigated. In addition, three necessary and sufficient conditions for LIA-filters are discussed. The obtained results may serve as some theoretical supports to lattice-valued logical system. 展开更多
关键词 Partially ordered set LATTICE Lattice filters Lattice implication algebra filterS
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Variational Bayesian labeled multi-Bernoulli filter with unknown sensor noise statistics 被引量:5
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作者 Qiu Hao Huang Gaoming Gao Jun 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2016年第5期1378-1384,共7页
It is difficult to build accurate model for measurement noise covariance in complex backgrounds. For the scenarios of unknown sensor noise variances, an adaptive multi-target tracking algorithm based on labeled random... It is difficult to build accurate model for measurement noise covariance in complex backgrounds. For the scenarios of unknown sensor noise variances, an adaptive multi-target tracking algorithm based on labeled random finite set and variational Bayesian (VB) approximation is proposed. The variational approximation technique is introduced to the labeled multi-Bernoulli (LMB) filter to jointly estimate the states of targets and sensor noise variances. Simulation results show that the proposed method can give unbiased estimation of cardinality and has better performance than the VB probability hypothesis density (VB-PHD) filter and the VB cardinality balanced multi-target multi-Bernoulli (VB-CBMeMBer) filter in harsh situations. The simulations also confirm the robustness of the proposed method against the time-varying noise variances. The computational complexity of proposed method is higher than the VB-PHD and VB-CBMeMBer in extreme cases, while the mean execution times of the three methods are close when targets are well separated. 展开更多
关键词 Labeled random finite set Multi-Bernoulli filter Multi-target tracking Parameter estimation Variational Bayesian approximation
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S-rough sets and knowledge separation 被引量:104
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作者 Shi Kaiquan 1,21. School of Mathematics and System Sciences, Liaocheng University, Liaocheng 252059, P. R. China 2. School of Mathematics and System Sciences, Shandong University, Jinan 250100, P. R. China 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2005年第2期403-410,共8页
The conceptions of the knowledge screen generated by S-rough sets are given: f- screen and - screen , and then puts forward - filter theorem, - filter theorem of knowledge. At last, the applications of knowledge separ... The conceptions of the knowledge screen generated by S-rough sets are given: f- screen and - screen , and then puts forward - filter theorem, - filter theorem of knowledge. At last, the applications of knowledge separation are given according to - screen and - screen. 展开更多
关键词 S- rough sets f- screen - screen f-filter theorem - filter theorem knowledge separation.
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Filtering-efficiency measurement of Chinese-made filter 1by double-filter method
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作者 ZHI Min (Shanghai Institute of Nuclear Rcsearrh, the Chinese Academy of Sciences, Shanghai 201800) 《Nuclear Science and Techniques》 SCIE CAS CSCD 1999年第3期168-170,共3页
Filtering efficiency of the Chinese-made filter 1 has been measured by the double-filter method with only one set of measurement equipment. The β counts of the two filters are measured in turn for every 3 minutes, fr... Filtering efficiency of the Chinese-made filter 1 has been measured by the double-filter method with only one set of measurement equipment. The β counts of the two filters are measured in turn for every 3 minutes, from which the decay constants are extracted to be 0.0131 min-1 and 0.0129 min-1 for the first and second filter respectively. After correcting the β counts of the second filter, the filtering efficiency of the filter is obtained to be (87.4±0.7)% in average. 展开更多
关键词 滤波器 双重滤波方法 滤波效率
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The Application of Rough Set Theory in Pseudo-BCK-Algebra
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作者 Xiaoyan MAO Huijie ZHOU 《Journal of Mathematical Research with Applications》 CSCD 2016年第1期23-35,共13页
In this paper, we apply the rough set theory to pseudo-BCK-algebras. As a generalization of pseudo-BCK-algebras, the notions of rough pseudo-BCK-algebras, rough subalgebras and rough pseudo-filters are introduced and ... In this paper, we apply the rough set theory to pseudo-BCK-algebras. As a generalization of pseudo-BCK-algebras, the notions of rough pseudo-BCK-algebras, rough subalgebras and rough pseudo-filters are introduced and some of their properties are discussed in an algebra-like approximation space. Furthermore, we investigate rough subalgebras and rough pseudo-filters in a pseudo-BCK-algebra approximation space. Finally, we give several verification programs of pseudo-BCK-algebras, pseudo-filters and subalgebra. 展开更多
关键词 lower and upper approximation pseudo-BCK-algebra pseudo-filter rough set SUBALGEBRA
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Synthesis of Fractional-order PI Controllers and Fractional-order Filters for Industrial Electrical Drives 被引量:1
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作者 Paolo Lino Guido Maione +2 位作者 Silvio Stasi Fabrizio Padula Antonio Visioli 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2017年第1期58-69,共12页
This paper introduces an electrical drives control architecture combining a fractional-order controller and a setpoint pre-filter. The former is based on a fractional-order proportional-integral(PI) unit, with a non-i... This paper introduces an electrical drives control architecture combining a fractional-order controller and a setpoint pre-filter. The former is based on a fractional-order proportional-integral(PI) unit, with a non-integer order integral action, while the latter can be of integer or non-integer type. To satisfy robustness and dynamic performance specifications, the feedback controller is designed by a loop-shaping technique in the frequency domain. In particular, optimality of the feedback system is pursued to achieve input-output tracking. The setpoint pre-filter is designed by a dynamic inversion technique minimizing the difference between the ideal synthesized command signal(i.e., a smooth monotonic response) and the prefilter step response. Experimental tests validate the methodology and compare the performance of the proposed architecture with well-established control schemes that employ the classical PIbased symmetrical optimum method with a smoothing pre-filter. 展开更多
关键词 Dynamic inversion electrical drives fractionalorder PI controller LOOP-SHAPING set-point pre-filter
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A Recursive Method to Encryption-Decryption-Based Distributed Set-Membership Filtering for Time-Varying Saturated Systems Over Sensor Networks
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作者 Jun Hu Jiaxing Li +2 位作者 Chaoqing Jia Xiaojian Yi Hongjian Liu 《IEEE/CAA Journal of Automatica Sinica》 2025年第5期1047-1049,共3页
Dear Editor,This letter deals with the distributed recursive set-membership filtering(DRSMF)issue for state-saturated systems under encryption-decryption mechanism.To guarantee the data security,the encryption-decrypt... Dear Editor,This letter deals with the distributed recursive set-membership filtering(DRSMF)issue for state-saturated systems under encryption-decryption mechanism.To guarantee the data security,the encryption-decryption mechanism is considered in the signal transmission process.Specifically,a novel DRSMF scheme is developed such that,for both state saturation and encryption-decryption mechanism,the filtering error(FE)is limited to the ellipsoid domain.Then,the filtering error constraint matrix(FECM)is computed and a desirable filter gain is derived by minimizing the FECM.Besides,the bound-edness evaluation of the FECM is provided. 展开更多
关键词 time varying saturated systems signal transmission processspecificallya encryption decryption mechanism sensor networks recursive method distributed set membership filtering
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Image Filter for Removal of Impulse Noise Based on Directional Derivatives 被引量:2
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作者 KONG Tao, LI Jun-li, CHEN Gang (College of Information Science and Engineering, Ningbo University, Ningbo 315211, China) 《Computer Aided Drafting,Design and Manufacturing》 2008年第2期91-102,共12页
One of the most common image processing tasks involves the removal of noise from images. Noise can be introduced during image capture, during transmission, or during storage. For design purposes, noise sources are fre... One of the most common image processing tasks involves the removal of noise from images. Noise can be introduced during image capture, during transmission, or during storage. For design purposes, noise sources are frequently approximated by random variables with a known probability distribution. One common noise model corrupts a signal by introducing impulses. And the surface of the image disturbed by impulse noise displays many peaks or vales. According to the characteristic of impulse noise, a novel algorithm is proposed to the detection of impulse noise point from images based on directional derivatives. First, the theory of calculus on directional derivatives is introduced in detail. Then it is applied to the field of image to removing noise with the discrete form derived from its continuous mathematical model. And a number of contrasting simulations illustrate that our algorithm not only can preserve the structure information while removing impulse noise but also can mostly save the gray value of the pixels undisturbed by noise. In addition, the comparisons of the filtering performance for removing impulse noise are analyzed in detail in the case of different noise densities, and also show that the algorithm suggested outperforms the conventional filter algorithms such as mean filter, median filter and so on in speed and impulse noise reduction, especially in random-valued impulse noise reduction. So it is a very good alternative to the existing schemes. 展开更多
关键词 level sets directional derivatives impulse noise median filter
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红外图像边缘自适应增强方法研究
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作者 张沛朋 宋学坤 《电子器件》 2025年第6期1274-1279,共6页
红外图像的边缘细节与传统图像不同,其与噪声同时存在,强边缘、弱边缘难以划分,自适应性差,影响图像增强质量。提出一种红外图像边缘自适应增强方法。通过改进的Canny算法提取图像边缘,采用改进的自适应中值滤波器对提取的图像进行去噪... 红外图像的边缘细节与传统图像不同,其与噪声同时存在,强边缘、弱边缘难以划分,自适应性差,影响图像增强质量。提出一种红外图像边缘自适应增强方法。通过改进的Canny算法提取图像边缘,采用改进的自适应中值滤波器对提取的图像进行去噪处理,根据梯度幅值和方向,完成非极大值抑制。通过OTSU算法划分图像区域,提取划分后的图像边缘,引入模糊集理论对红外图像的强边缘、弱边缘和噪声分别进行处理,并采用模糊特征平面自适应调节加权系数,分别调节强边缘、弱边缘和噪声,完成红外图像边缘自适应增强。实验结果表明:所提方法的信噪比在4.2左右,绝对均值误差在0.05以下,说明该方法能够有效增强图像边缘,且增强后图像信噪比和结构相似度高、绝对误差均值低。 展开更多
关键词 红外图像 边缘自适应增强 边缘提取 自适应中值滤波 模糊集理论
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伪BE代数的双极值模糊滤子
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作者 姜曼 《安徽大学学报(自然科学版)》 北大核心 2025年第1期19-26,共8页
把双极值模糊集与伪BE代数相结合,首先在伪BE代数中给出了双极值模糊滤子的概念并讨论其性质,研究了双极值模糊集是双极值模糊滤子的条件;其次在伪BE代数中定义了双极值模糊交换滤子;最后讨论了双极值模糊滤子与双极值模糊交换滤子的关系.
关键词 伪BE代数 双极值模糊集 双极值模糊滤子 双极值模糊交换滤子
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基于中心差分扩展集员滤波的融合室内定位算法 被引量:1
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作者 吴晓烨 何青 +1 位作者 李灵 张杏 《传感器与微系统》 北大核心 2025年第5期112-114,119,共4页
针对室内复杂环境下单一定位技术难以满足高精度定位需求的问题,提出了一种用于非线性系统状态估计的中心差分扩展集员滤波(CDESMF)算法来融合超宽带(UWB)和惯性测量单元(IMU)的测量信息。为了克服泰勒展开的固有缺陷,采用低阶多维斯特... 针对室内复杂环境下单一定位技术难以满足高精度定位需求的问题,提出了一种用于非线性系统状态估计的中心差分扩展集员滤波(CDESMF)算法来融合超宽带(UWB)和惯性测量单元(IMU)的测量信息。为了克服泰勒展开的固有缺陷,采用低阶多维斯特林插值公式代替泰勒展开将非线性系统线性化,以提高算法精度并且有效抑制数据的抖动。实验结果表明:本文研究的融合算法定位精度在5 cm以内,比扩展卡尔曼滤波(EKF)融合算法定位精度提高了21%。 展开更多
关键词 集员滤波 超宽带 惯性测量单元 室内定位
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