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RBAC模型层次关系中的角色权限 被引量:17
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作者 顾春华 肖宝亮 《华东理工大学学报(自然科学版)》 EI CAS CSCD 北大核心 2007年第1期96-99,共4页
针对RBAC96模型中角色的私有权限处理方法的不足,从实现的角度提出了一个改进模型。通过公有继承方式和角色权限转换,使角色的私有权限得以保护,公有权限的继承层次得以简单灵活的控制,解决了由于角色继承而复杂化的角色基数问题。并以... 针对RBAC96模型中角色的私有权限处理方法的不足,从实现的角度提出了一个改进模型。通过公有继承方式和角色权限转换,使角色的私有权限得以保护,公有权限的继承层次得以简单灵活的控制,解决了由于角色继承而复杂化的角色基数问题。并以面向对象的方法实现了此模型。 展开更多
关键词 基于角色的访问控制 私有权限 权限转换 基数
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Cardinality compensation method based on information-weighted consensus filter using data clustering for multi-target tracking 被引量:4
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作者 Sunyoung KIM Changho KANG Changook PARK 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2019年第9期2164-2173,共10页
In this paper, a cardinality compensation method based on Information-weighted Consensus Filter(ICF) using data clustering is proposed in order to accurately estimate the cardinality of the Cardinalized Probability Hy... In this paper, a cardinality compensation method based on Information-weighted Consensus Filter(ICF) using data clustering is proposed in order to accurately estimate the cardinality of the Cardinalized Probability Hypothesis Density(CPHD) filter. Although the joint propagation of the intensity and the cardinality distribution in the CPHD filter process allows for more reliable estimation of the cardinality(target number) than the PHD filter, tracking loss may occur when noise and clutter are high in the measurements in a practical situation. For that reason, the cardinality compensation process is included in the CPHD filter, which is based on information fusion step using estimated cardinality obtained from the CPHD filter and measured cardinality obtained through data clustering. Here, the ICF is used for information fusion. To verify the performance of the proposed method, simulations were carried out and it was confirmed that the tracking performance of the multi-target was improved because the cardinality was estimated more accurately as compared to the existing techniques. 展开更多
关键词 cardinality compensation cardinalized probability HYPOTHESIS density FILTER Data clustering Information-weighted consensus FILTER MULTI-TARGET tracking
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The Erdös-Faber-Lovász Conjecture for Gap-Restricted Hypergraphs
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作者 Zhimin Wang 《Engineering(科研)》 2024年第2期47-59,共13页
An edge coloring of hypergraph H is a function   such that  holds for any pair of intersecting edges . The minimum number of colors in edge colorings of H is called the chromatic index of H and is ... An edge coloring of hypergraph H is a function   such that  holds for any pair of intersecting edges . The minimum number of colors in edge colorings of H is called the chromatic index of H and is denoted by . Erdös, Faber and Lovász proposed a famous conjecture that  holds for any loopless linear hypergraph H with n vertices. In this paper, we show that  is true for gap-restricted hypergraphs. Our result extends a result of Alesandroni in 2021. 展开更多
关键词 Linear Hypergraph Chromatic Index Erdös-Faber-Lovász Conjecture Edge cardinality
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模糊集的基数与连续统假设 被引量:5
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作者 李洪兴 罗承忠 汪培庄 《Journal of Mathematical Research and Exposition》 CSCD 1995年第1期129-134,共6页
本文在模糊映射 ̄[1]的基础上给出了模糊集基数的定义,它把普通集的基数作为特款;不但得到有关基数的大部分结论,而且有其自身的特殊性质;特别,对于连续统假设这一世界难题可能有新的启示.
关键词 模糊映射 连续统假设 模糊集 基数
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Cardinality Estimator:Processing SQL with a Vertical Scanning Convolutional Neural Network 被引量:5
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作者 Shao-Jie Qiao Guo-Ping Yang +5 位作者 Nan Han Hao Chen Fa-Liang Huang Kun Yue Yu-Gen Yi Chang-An Yuan 《Journal of Computer Science & Technology》 SCIE EI CSCD 2021年第4期762-777,共16页
Although the popular database systems perform well on query optimization,they still face poor query execution plans when the join operations across multiple tables are complex.Bad execution planning usually results in... Although the popular database systems perform well on query optimization,they still face poor query execution plans when the join operations across multiple tables are complex.Bad execution planning usually results in bad cardinality estimations.The cardinality estimation models in traditional databases cannot provide high-quality estimation,because they are not capable of capturing the correlation between multiple tables in an effective fashion.Recently,the state-of-the-art learning-based cardinality estimation is estimated to work better than the traditional empirical methods.Basically,they used deep neural networks to compute the relationships and correlations of tables.In this paper,we propose a vertical scanning convolutional neural network(abbreviated as VSCNN)to capture the relationships between words in the word vector in order to generate a feature map.The proposed learning-based cardinality estimator converts Structured Query Language(SQL)queries from a sentence to a word vector and we encode table names in the one-hot encoding method and the samples into bitmaps,separately,and then merge them to obtain enough semantic information from data samples.In particular,the feature map obtained by VSCNN contains semantic information including tables,joins,and predicates about SQL queries.Importantly,in order to improve the accuracy of cardinality estimation,we propose the negative sampling method for training the word vector by gradient descent from the base table and compress it into a bitmap.Extensive experiments are conducted and the results show that the estimation quality of q-error of the proposed vertical scanning convolutional neural network based model is reduced by at least 14.6%when compared with the estimators in traditional databases. 展开更多
关键词 cardinality estimation word vector vertical scanning convolutional neural network sampling method
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一类带限的插值小波(英文) 被引量:4
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作者 刘有明 G.G.Walter 《数学进展》 CSCD 北大核心 1997年第6期523-528,共6页
Shannon尺度函数具有带限性质、正交性质、取样性质,但它不在L(R)中.本文引入一类新的小波,它的尺度函数不仅具有上述性质而且在L(R)中,甚至更多.
关键词 小波 尺度函数 带限 多尺度分析 插值小波
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言语数词习得的认知基础
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作者 牟毅 《北京师范大学学报(社会科学版)》 CSSCI 北大核心 2024年第3期64-71,共8页
儿童从学前期开始学习言语数词(如理解数词的数量含义),但其认知基础为何尚有很大争议。现有研究聚焦检查儿童的数词概念是否建立于自婴儿期就具有的非言语数能力基础上。考虑到非言语数能力受到至少两个不同的数认知系统的支持(近似数... 儿童从学前期开始学习言语数词(如理解数词的数量含义),但其认知基础为何尚有很大争议。现有研究聚焦检查儿童的数词概念是否建立于自婴儿期就具有的非言语数能力基础上。考虑到非言语数能力受到至少两个不同的数认知系统的支持(近似数量系统和物体追踪系统),研究者检查数词概念习得是否依赖于这些数认知系统,并发展出四种假设:近似数量系统假设,物体追踪系统假设,双系统假设和独立假设。这些假设均有其合理性和局限性,检验四种假设的关键是同时纳入两个非言语数认知系统并对比它们对数词习得的贡献。在这个检验思路中,未来研究需提供追踪和干预训练数据检查两个非言语数认知系统和数词习得的关系,且将之在行为和大脑认知神经层面交叉印证;此外,对这些关系的检查还需注意区分儿童数词学习的不同阶段,并考虑其他一般性认知能力的影响。 展开更多
关键词 言语数词 基数性 继位性 近似数量系统 物体追踪系统
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基于Bloom Filter本地差分隐私的基数估计
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作者 邱彩 王俊清 傅继彬 《科技创新与应用》 2024年第28期35-38,共4页
计算机技术和通信技术的共同发展,使得数据呈现指数大爆炸式的增长。数据中蕴含的巨大价值是有目共睹的。但是对数据集的肆意收集与分析,使用户的隐私数据处在被泄露的风险中。为保护用户的敏感数据的同时实现对基数查询的有效响应,提... 计算机技术和通信技术的共同发展,使得数据呈现指数大爆炸式的增长。数据中蕴含的巨大价值是有目共睹的。但是对数据集的肆意收集与分析,使用户的隐私数据处在被泄露的风险中。为保护用户的敏感数据的同时实现对基数查询的有效响应,提出一种基于差分隐私的隐私保护算法BFRRCE(Bloom Filter Random Response for Cardinality Estimation)。首先对用户的数据利用Bloom Filter数据结构进行数据预处理,然后利用本地差分隐私的扰动算法对数据进行扰动,达到保护用户敏感数据的目的。 展开更多
关键词 隐私保护 本地化差分隐私 Bloom Filter 基数 随机响应
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Adaptive Algorithms on Maximizing Monotone Nonsubmodular Functions
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作者 Bin Liu Hui Su +1 位作者 Shu-Fang Gong Qi-Zhi Fang 《Journal of the Operations Research Society of China》 EI CSCD 2024年第2期428-445,共18页
Submodular optimization is widely used in large datasets.In order to speed up the problems solving,it is essential to design low-adaptive algorithms to achieve acceleration in parallel.In general,the function values a... Submodular optimization is widely used in large datasets.In order to speed up the problems solving,it is essential to design low-adaptive algorithms to achieve acceleration in parallel.In general,the function values are given by a value oracle,but in practice,the oracle queries may consume a lot of time.Hence,how to strike a balance between optimizing them is important.In this paper,we focus on maximizing a normalized and strictly monotone set function with the diminishing-return ratio under a cardinality constraint,and propose two algorithms to deal with it.We apply the adaptive sequencing technique to devise the first algorithm,whose approximation ratio is arbitrarily close to 1-e^(-γ)in O(logn·log(log k/γ)) adaptive rounds,and requires O(logn^(2)·log(log k/γ)) queries.Then by adding preprocessing and parameter estimation steps to the first algorithm,we get the second one.The second algorithm trades a small sacrifice in adaptive complexity for a significant improvement in query complexity.With the same approximation and adaptive complexity,the query complexity is improved to.To the best of our knowledge,this is the first paper of designing adaptive algorithms for maximizing a monotone function using the diminishing-return ratio. 展开更多
关键词 Approximation algorithm Adaptivity Nonsubmodular maximization cardinality constraint
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Scientific Elegance in NIDS: Unveiling Cardinality Reduction, Box-Cox Transformation, and ADASYN for Enhanced Intrusion Detection
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作者 Amerah Alabrah 《Computers, Materials & Continua》 SCIE EI 2024年第6期3897-3912,共16页
The emergence of digital networks and the wide adoption of information on internet platforms have given rise to threats against users’private information.Many intruders actively seek such private data either for sale... The emergence of digital networks and the wide adoption of information on internet platforms have given rise to threats against users’private information.Many intruders actively seek such private data either for sale or other inappropriate purposes.Similarly,national and international organizations have country-level and company-level private information that could be accessed by different network attacks.Therefore,the need for a Network Intruder Detection System(NIDS)becomes essential for protecting these networks and organizations.In the evolution of NIDS,Artificial Intelligence(AI)assisted tools and methods have been widely adopted to provide effective solutions.However,the development of NIDS still faces challenges at the dataset and machine learning levels,such as large deviations in numeric features,the presence of numerous irrelevant categorical features resulting in reduced cardinality,and class imbalance in multiclass-level data.To address these challenges and offer a unified solution to NIDS development,this study proposes a novel framework that preprocesses datasets and applies a box-cox transformation to linearly transform the numeric features and bring them into closer alignment.Cardinality reduction was applied to categorical features through the binning method.Subsequently,the class imbalance dataset was addressed using the adaptive synthetic sampling data generation method.Finally,the preprocessed,refined,and oversampled feature set was divided into training and test sets with an 80–20 ratio,and two experiments were conducted.In Experiment 1,the binary classification was executed using four machine learning classifiers,with the extra trees classifier achieving the highest accuracy of 97.23%and an AUC of 0.9961.In Experiment 2,multiclass classification was performed,and the extra trees classifier emerged as the most effective,achieving an accuracy of 81.27%and an AUC of 0.97.The results were evaluated based on training,testing,and total time,and a comparative analysis with state-of-the-art stud 展开更多
关键词 Adaptive synthetic sampling class imbalance features cardinality network security over sampling
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AN INEXACT PROXIMAL DC ALGORITHM FOR THE LARGE-SCALE CARDINALITY CONSTRAINED MEAN-VARIANCE MODEL IN SPARSE PORTFOLIO SELECTION
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作者 Mingcai Ding Xiaoliang Song Bo Yu 《Journal of Computational Mathematics》 SCIE CSCD 2024年第6期1452-1501,共50页
Optimization problem of cardinality constrained mean-variance(CCMV)model for sparse portfolio selection is considered.To overcome the difficulties caused by cardinality constraint,an exact penalty approach is employed... Optimization problem of cardinality constrained mean-variance(CCMV)model for sparse portfolio selection is considered.To overcome the difficulties caused by cardinality constraint,an exact penalty approach is employed,then CCMV problem is transferred into a difference-of-convex-functions(DC)problem.By exploiting the DC structure of the gained problem and the superlinear convergence of semismooth Newton(ssN)method,an inexact proximal DC algorithm with sieving strategy based on a majorized ssN method(siPDCA-mssN)is proposed.For solving the inner problems of siPDCA-mssN from dual,the second-order information is wisely incorporated and an efficient mssN method is employed.The global convergence of the sequence generated by siPDCA-mssN is proved.To solve large-scale CCMV problem,a decomposed siPDCA-mssN(DsiPDCA-mssN)is introduced.To demonstrate the efficiency of proposed algorithms,siPDCA-mssN and DsiPDCA-mssN are compared with the penalty proximal alternating linearized minimization method and the CPLEX(12.9)solver by performing numerical experiments on realword market data and large-scale simulated data.The numerical results demonstrate that siPDCA-mssN and DsiPDCA-mssN outperform the other methods from computation time and optimal value.The out-of-sample experiments results display that the solutions of CCMV model are better than those of other portfolio selection models in terms of Sharp ratio and sparsity. 展开更多
关键词 Sparse portfolio selection cardinality constrained mean-variance model Inexact proximal difference-of-convex-functions algorithm Sieving strategy Decomposed strategy
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关于欧几里得空间E^d中的二距离集 被引量:2
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作者 徐士英 《中国计量学院学报》 2002年第1期16-18,26,共4页
本文对欧几里得空间 Ed
关键词 二距离集 上界
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HLA中基于OMT文件创建数据库关系表的方法 被引量:3
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作者 鞠儒生 乔海泉 +1 位作者 陈少卿 黄柯棣 《计算机仿真》 CSCD 2006年第5期119-122,共4页
针对高层体系结构(HLA)仿真结果数据日益增多,数据类型多变以及数据关系极其复杂的情况,介绍了利用HLA中对象模型模板(OMT)文件创建数据库关系表的通用方法。根据一般关系表的创建过程,分析了利用OMT文件中的数据定义,分别确定数据库关... 针对高层体系结构(HLA)仿真结果数据日益增多,数据类型多变以及数据关系极其复杂的情况,介绍了利用HLA中对象模型模板(OMT)文件创建数据库关系表的通用方法。根据一般关系表的创建过程,分析了利用OMT文件中的数据定义,分别确定数据库关系表名称、字段名以及字段类型的原理。对OMT中类名过长及重复的问题,设计采用映射表的处理方法。对OMT文件中比较复杂的定义类型,包括多粒度或变粒度下简单数据类型、复杂数据类型以及嵌套复杂数据类型,详细分析了其对应的建表设计方案。最后根据实际仿真的需要,说明了关系表附加字段的选取过程。根据上述思路,设计开发了对应的工程软件,软件的成功应用证明了设计方案的有效性。 展开更多
关键词 仿真结果数据 层体系结构 象模型模板
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Recent Advances in Mathematical Programming with Semi-continuous Variables and Cardinality Constraint 被引量:3
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作者 Xiaoling Sun Xiaojin Zheng Duan Li 《Journal of the Operations Research Society of China》 EI 2013年第1期55-77,共23页
Mathematical programming problems with semi-continuous variables and cardinality constraint have many applications,including production planning,portfolio selection,compressed sensing and subset selection in regressio... Mathematical programming problems with semi-continuous variables and cardinality constraint have many applications,including production planning,portfolio selection,compressed sensing and subset selection in regression.This class of problems can be modeled as mixed-integer programs with special structures and are in general NP-hard.In the past few years,based on new reformulations,approximation and relaxation techniques,promising exact and approximate methods have been developed.We survey in this paper these recent developments for this challenging class of mathematical programming problems. 展开更多
关键词 Semi-continuous variables cardinality and sparsity constraint Mixed-integer 0-1 quadratic programming Perspective reformulation Lagrangian decomposition Approximate methods
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Portfolio Optimization under Cardinality Constraints: A Comparative Study
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作者 Henri Claver Jimbo Isidore Seraphin Ngongo +2 位作者 Nicolas Gabriel Andjiga Takeru Suzuki Charles Awona Onana 《Open Journal of Statistics》 2017年第4期731-742,共12页
The Cardinality Constraint-Based Optimization problem is investigated in this note. In portfolio optimization problem, the cardinality constraint allows one to invest in assets out of a universe of N assets for a pres... The Cardinality Constraint-Based Optimization problem is investigated in this note. In portfolio optimization problem, the cardinality constraint allows one to invest in assets out of a universe of N assets for a prespecified value of K. It is generally agreed that choosing a “small” value of K forces the implementation of diversification in small portfolios. However, the question of how small must be K has remained unanswered. In the present work, using a comparative approach we show computationally that optimal portfolio selection with a relatively small or large number of assets, K, may produce similar results with differentiated reliabilities. 展开更多
关键词 cardinality CONSTRAINTS DIVERSITY PORTFOLIO Selection PORTFOLIO Reliability PARAMETRIC STATISTICS
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On the Decomposition of a Bounded Closed Interval of the Real Line into Closed Sets
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作者 Edgar A. Cohen 《Advances in Pure Mathematics》 2013年第4期405-408,共4页
It has been shown by Sierpinski that a compact, Hausdorff, connected topological space (otherwise known as a continuum) cannot be decomposed into either a finite number of two or more disjoint, nonempty, closed sets o... It has been shown by Sierpinski that a compact, Hausdorff, connected topological space (otherwise known as a continuum) cannot be decomposed into either a finite number of two or more disjoint, nonempty, closed sets or a countably infinite family of such sets. In particular, for a closed interval of the real line endowed with the usual topology, we see that we cannot partition it into a countably infinite number of disjoint, nonempty closed sets. On the positive side, however, one can certainly express such an interval as a union of c disjoint closed sets, where c is the cardinality of the real line. For example, a closed interval is surely the union of its points, each set consisting of a single point being closed. Surprisingly enough, except for a set of Lebesgue measure 0, these closed sets can be chosen to be perfect sets, i.e., closed sets every point of which is an accumulation point. They even turn out to be nowhere dense (containing no intervals). Such nowhere dense, perfect sets are sometimes called Cantor sets. 展开更多
关键词 CANTOR SETS cardinality DISJOINT Closed SETS DYADIC Representation INTERLACING DYADIC Expansions Generators of SETS Nowhere Dense
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A note on spline wavelets
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作者 LIU YoumingDepartment of Applied Mathematics, Beijing Polytechnic University, Beijing 100022, China 《Chinese Science Bulletin》 SCIE EI CAS 1997年第15期1250-1253,共4页
THE B-spline wavelets N<sub>m</sub> (x) play an important role in the approximation theory sincethey are piecewise polynomials so that they may be used to fit a function and its derivatives atthe integer... THE B-spline wavelets N<sub>m</sub> (x) play an important role in the approximation theory sincethey are piecewise polynomials so that they may be used to fit a function and its derivatives atthe integers. However, except for m=1, 2, they do not have the interpolating property (i.e. N<sub>m</sub>(n) ≠δ<sub>n0</sub>. In this work, we shall construct a family of scaling functions of fatherwavelets which have the interpolating property and whose Fourier transforms are spline func-tions. As usual, these functions can be orthogonalized by Meyer’s technique and the corre-sponding mother wavelets ψ may be found by the 展开更多
关键词 WAVELETS SCALING FUNCTION cardinality.
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Construction of New Codes from Given Ones in an Additive Channel
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作者 Garib Movsisyan 《Journal of Information Security》 2016年第3期165-171,共7页
In the present work, a construction making possible creation of an additive channel  of cardinality s and rank r for arbitrary integers s, r, n (r≤min (n,s-1)), as well as creation of a code  correcting err... In the present work, a construction making possible creation of an additive channel  of cardinality s and rank r for arbitrary integers s, r, n (r≤min (n,s-1)), as well as creation of a code  correcting errors of the channel A is presented. 展开更多
关键词 Additive Channel Golay Code Classical Coding Theory T-Order Neighborhood Correcting Code Binary Alphabet cardinality
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Fast counting the cardinality of flows for big traffic over sliding windows
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作者 Jingsong SHAN Yinjin FU +2 位作者 Guiqiang NI Jianxin LUO Zhaofeng WU 《Frontiers of Computer Science》 SCIE EI CSCD 2017年第1期119-129,共11页
Counting the cardinality of flows for massive high-speed traffic over sliding windows is still a challenging work under time and space constrains, but plays a key role in many network applications, such as traffic man... Counting the cardinality of flows for massive high-speed traffic over sliding windows is still a challenging work under time and space constrains, but plays a key role in many network applications, such as traffic management and routing optimization in software defined network. In this pa- per, we propose a novel data structure (called LRU-Sketch) to address the problem. The significant contributions are as follows. 1) The proposed data structure adapts a well-known probabilistic sketch to sliding window model; 2) By using the least-recently used (LRU) replacement policy, we design a highly time-efficient algorithm for timely forgetting stale information, which takes constant (O(1)) time per time slot; 3) Moreover, a further memory-reducing schema is given at a cost of very little loss of accuracy; 4) Comprehensive ex- periments, performed on two real IP trace files, confirm that the proposed schema attains high accuracy and high time efficiency.ferences including IEEE TPDS, ACM ToS, JCST, MIDDLEWARE, CLUSTER, NAS, etc. Currently, his research interests include big data management, cloud storage, and distributed file systems. 展开更多
关键词 probabilistic data structure SKETCH streaming data cardinality flow
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Semi-quantum protocol for cardinalities of private set intersection and union based on GHZ states
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作者 Zhang Long Wang Weijian Zhang Kejia 《The Journal of China Universities of Posts and Telecommunications》 EI CSCD 2022年第4期69-76,105,共9页
In modern society,it is necessary to perform some secure computations for private sets between different entities.For instance,two merchants desire to calculate the number of common customers and the total number of u... In modern society,it is necessary to perform some secure computations for private sets between different entities.For instance,two merchants desire to calculate the number of common customers and the total number of users without disclosing their own privacy.In order to solve the referred problem,a semi-quantum protocol for private computation of cardinalities of set based on Greenberger-Horne-Zeilinger(GHZ)states is proposed for the first time in this paper,where all the parties just perform single-particle measurement if necessary.With the assistance of semi-honest third party(TP),two semi-quantum participants can simultaneously obtain intersection cardinality and union cardinality.Furthermore,security analysis shows that the presented protocol can stand against some well-known quantum attacks,such as intercept measure resend attack,entangle measure attack.Compared with the existing quantum protocols of Private Set Intersection Cardinality(PSI-CA)and Private Set Union Cardinality(PSU-CA),the complicated oracle operations and powerful quantum capacities are not required in the proposed protocol.Therefore,it seems more appropriate to implement this protocol with current technology. 展开更多
关键词 quantum communication private set intersection cardinality private set union cardinality secure multiparty computation
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