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CRB:A new rumor blocking algorithm in online social networks based on competitive spreading model and influence maximization
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作者 董晨 徐桂琼 孟蕾 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第8期588-604,共17页
The virtuality and openness of online social platforms make networks a hotbed for the rapid propagation of various rumors.In order to block the outbreak of rumor,one of the most effective containment measures is sprea... The virtuality and openness of online social platforms make networks a hotbed for the rapid propagation of various rumors.In order to block the outbreak of rumor,one of the most effective containment measures is spreading positive information to counterbalance the diffusion of rumor.The spreading mechanism of rumors and effective suppression strategies are significant and challenging research issues.Firstly,in order to simulate the dissemination of multiple types of information,we propose a competitive linear threshold model with state transition(CLTST)to describe the spreading process of rumor and anti-rumor in the same network.Subsequently,we put forward a community-based rumor blocking(CRB)algorithm based on influence maximization theory in social networks.Its crucial step is to identify a set of influential seeds that propagate anti-rumor information to other nodes,which includes community detection,selection of candidate anti-rumor seeds and generation of anti-rumor seed set.Under the CLTST model,the CRB algorithm has been compared with six state-of-the-art algorithms on nine online social networks to verify the performance.Experimental results show that the proposed model can better reflect the process of rumor propagation,and review the propagation mechanism of rumor and anti-rumor in online social networks.Moreover,the proposed CRB algorithm has better performance in weakening the rumor dissemination ability,which can select anti-rumor seeds in networks more accurately and achieve better performance in influence spread,sensitivity analysis,seeds distribution and running time. 展开更多
关键词 online social networks rumor blocking competitive linear threshold model influence maximization
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An Influence Maximization Algorithm Based on the Mixed Importance of Nodes 被引量:1
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作者 Yong Hua Bolun Chen +2 位作者 Yan Yuan Guochang Zhu Jialin Ma 《Computers, Materials & Continua》 SCIE EI 2019年第5期517-531,共15页
The influence maximization is the problem of finding k seed nodes that maximize the scope of influence in a social network.Therefore,the comprehensive influence of node needs to be considered,when we choose the most i... The influence maximization is the problem of finding k seed nodes that maximize the scope of influence in a social network.Therefore,the comprehensive influence of node needs to be considered,when we choose the most influential node set consisted of k seed nodes.On account of the traditional methods used to measure the influence of nodes,such as degree centrality,betweenness centrality and closeness centrality,consider only a single aspect of the influence of node,so the influence measured by traditional methods mentioned above of node is not accurate.In this paper,we obtain the following result through experimental analysis:the influence of a node is relevant not only to its degree and coreness,but also to the degree and coreness of the n-order neighbor nodes.Hence,we propose a algorithm based on the mixed importance of nodes to measure the comprehensive influence of node,and the algorithm we proposed is simple and efficient.In addition,the performance of the algorithm we proposed is better than that of traditional influence maximization algorithms. 展开更多
关键词 influence maximization social network mixed importance coreness
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An Influence Maximization Algorithm Based on Improved K-Shell in Temporal Social Networks 被引量:1
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作者 Wenlong Zhu Yu Miao +2 位作者 Shuangshuang Yang Zuozheng Lian Lianhe Cui 《Computers, Materials & Continua》 SCIE EI 2023年第5期3111-3131,共21页
Influence maximization of temporal social networks(IMT)is a problem that aims to find the most influential set of nodes in the temporal network so that their information can be the most widely spread.To solve the IMT ... Influence maximization of temporal social networks(IMT)is a problem that aims to find the most influential set of nodes in the temporal network so that their information can be the most widely spread.To solve the IMT problem,we propose an influence maximization algorithm based on an improved K-shell method,namely improved K-shell in temporal social networks(KT).The algorithm takes into account the global and local structures of temporal social networks.First,to obtain the kernel value Ks of each node,in the global scope,it layers the network according to the temporal characteristic of nodes by improving the K-shell method.Then,in the local scope,the calculation method of comprehensive degree is proposed to weigh the influence of nodes.Finally,the node with the highest comprehensive degree in each core layer is selected as the seed.However,the seed selection strategy of KT can easily lose some influential nodes.Thus,by optimizing the seed selection strategy,this paper proposes an efficient heuristic algorithm called improved K-shell in temporal social networks for influence maximization(KTIM).According to the hierarchical distribution of cores,the algorithm adds nodes near the central core to the candidate seed set.It then searches for seeds in the candidate seed set according to the comprehensive degree.Experiments showthatKTIMis close to the best performing improved method for influence maximization of temporal graph(IMIT)algorithm in terms of effectiveness,but runs at least an order of magnitude faster than it.Therefore,considering the effectiveness and efficiency simultaneously in temporal social networks,the KTIM algorithm works better than other baseline algorithms. 展开更多
关键词 Temporal social network influence maximization improved K-shell comprehensive degree
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Time sequential influence maximization algorithm based on neighbor node influence
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作者 CHEN Jing QI Ziyi LIU Mingxin 《High Technology Letters》 EI CAS 2022年第2期153-163,共11页
In view of the forwarding microblogging,secondhand smoke,happiness,and many other phenomena in real life,the spread characteristic of the secondary neighbor nodes in this kind of phenomenon and network scheduling is e... In view of the forwarding microblogging,secondhand smoke,happiness,and many other phenomena in real life,the spread characteristic of the secondary neighbor nodes in this kind of phenomenon and network scheduling is extracted,and sequence influence maximization problem based on the influence of neighbor nodes is proposed in this paper.That is,in the time sequential social network,the propagation characteristics of the second-level neighbor nodes are considered emphatically,and k nodes are found to maximize the information propagation.Firstly,the propagation probability between nodes is calculated by the improved degree estimation algorithm.Secondly,the weighted cascade model(WCM) based on static social network is not suitable for temporal social network.Therefore,an improved weighted cascade model(IWCM) is proposed,and a second-level neighbors time sequential maximizing influence algorithm(STIM) is put forward based on node degree.It combines the consideration of neighbor nodes and the problem of overlap of influence scope between nodes,and makes it chronological.Finally,the experiment verifies that STIM algorithm has stronger practicability,superiority in influence range and running time compared with similar algorithms,and is able to solve the problem of maximizing the timing influence based on the influence of neighbor nodes. 展开更多
关键词 neighbor node influence time sequential social network influence maximization(im) information propagation model
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An Influence Maximization Algorithm Based on the Influence Propagation Range of Nodes
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作者 Yong Hua Bolun Chen +2 位作者 Yan Yuan Guochang Zhu Fenfen Li 《Journal on Internet of Things》 2019年第2期77-88,共12页
The problem of influence maximization in the social network G is to find k seed nodes with the maximum influence.The seed set S has a wider range of influence in the social network G than other same-size node sets.The... The problem of influence maximization in the social network G is to find k seed nodes with the maximum influence.The seed set S has a wider range of influence in the social network G than other same-size node sets.The influence of a node is usually established by using the IC model(Independent Cascade model)with a considerable amount of Monte Carlo simulations used to approximate the influence of the node.In addition,an approximate effect(1􀀀1=e)is obtained,when the number of Monte Carlo simulations is 10000 and the probability of propagation is very small.In this paper,we analyze that the propagative range of influence of node set is limited in the IC model,and we find that the influence of node only spread to the t0-th neighbor.Therefore,we propose a greedy algorithm based on the improved IC model that we only consider the influence in the t0-th neighbor of node.Finally,we perform experiments on 10 real social network and achieve favorable results. 展开更多
关键词 influence maximization social network IC RANGE
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Maximizing Influence in Temporal Social Networks:A Node Feature-Aware Voting Algorithm
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作者 Wenlong Zhu Yu Miao +2 位作者 Shuangshuang Yang Zuozheng Lian Lianhe Cui 《Computers, Materials & Continua》 SCIE EI 2023年第12期3095-3117,共23页
Influence Maximization(IM)aims to select a seed set of size k in a social network so that information can be spread most widely under a specific information propagation model through this set of nodes.However,most exi... Influence Maximization(IM)aims to select a seed set of size k in a social network so that information can be spread most widely under a specific information propagation model through this set of nodes.However,most existing studies on the IM problem focus on static social network features,while neglecting the features of temporal social networks.To bridge this gap,we focus on node features reflected by their historical interaction behavior in temporal social networks,i.e.,interaction attributes and self-similarity,and incorporate them into the influence maximization algorithm and information propagation model.Firstly,we propose a node feature-aware voting algorithm,called ISVoteRank,for seed nodes selection.Specifically,before voting,the algorithm sets the initial voting ability of nodes in a personalized manner by combining their features.During the voting process,voting weights are set based on the interaction strength between nodes,allowing nodes to vote at different extents and subsequently weakening their voting ability accordingly.The process concludes by selecting the top k nodes with the highest voting scores as seeds,avoiding the inefficiency of iterative seed selection in traditional voting-based algorithms.Secondly,we extend the Independent Cascade(IC)model and propose the Dynamic Independent Cascade(DIC)model,which aims to capture the dynamic features in the information propagation process by combining node features.Finally,experiments demonstrate that the ISVoteRank algorithm has been improved in both effectiveness and efficiency compared to baseline methods,and the influence spread through the DIC model is improved compared to the IC model. 展开更多
关键词 Temporal social networks influence maximization voting strategy interactive properties SELF-SimILARITY
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Identifying influential spreaders in social networks: A two-stage quantum-behaved particle swarm optimization with Lévy flight
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作者 卢鹏丽 揽继茂 +3 位作者 唐建新 张莉 宋仕辉 朱虹羽 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期743-754,共12页
The influence maximization problem aims to select a small set of influential nodes, termed a seed set, to maximize their influence coverage in social networks. Although the methods that are based on a greedy strategy ... The influence maximization problem aims to select a small set of influential nodes, termed a seed set, to maximize their influence coverage in social networks. Although the methods that are based on a greedy strategy can obtain good accuracy, they come at the cost of enormous computational time, and are therefore not applicable to practical scenarios in large-scale networks. In addition, the centrality heuristic algorithms that are based on network topology can be completed in relatively less time. However, they tend to fail to achieve satisfactory results because of drawbacks such as overlapped influence spread. In this work, we propose a discrete two-stage metaheuristic optimization combining quantum-behaved particle swarm optimization with Lévy flight to identify a set of the most influential spreaders. According to the framework,first, the particles in the population are tasked to conduct an exploration in the global solution space to eventually converge to an acceptable solution through the crossover and replacement operations. Second, the Lévy flight mechanism is used to perform a wandering walk on the optimal candidate solution in the population to exploit the potentially unidentified influential nodes in the network. Experiments on six real-world social networks show that the proposed algorithm achieves more satisfactory results when compared to other well-known algorithms. 展开更多
关键词 social networks influence maximization metaheuristic optimization quantum-behaved particle swarm optimization Lévy flight
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基于离散度及果蝇算法的关键节点识别算法
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作者 付立东 李东洋 《计算机工程与设计》 北大核心 2025年第3期648-656,共9页
针对现有算法在复杂网络中筛选出的关键节点过于密集、传播效率低的富人俱乐部(Rich-Club)现象,提出一种基于离散度及果蝇算法的关键节点识别算法。利用去除筛选网络中最大影响力节点,网络的流通性将会有最大程度损坏这一特性,定义离散... 针对现有算法在复杂网络中筛选出的关键节点过于密集、传播效率低的富人俱乐部(Rich-Club)现象,提出一种基于离散度及果蝇算法的关键节点识别算法。利用去除筛选网络中最大影响力节点,网络的流通性将会有最大程度损坏这一特性,定义离散度函数,采用香农熵对果蝇算法进行改进并优化,确定网络最优种子集。在多种类型规模网络上的实验结果表明,该方法能够有效识别复杂网络中具有传播范围更广的最大影响力节点。 展开更多
关键词 复杂网络 最大影响力节点 果蝇算法 离散度 香农熵 流通性 富人俱乐部
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一种预测未知节点的融合影响力最大化的知识可迁移GNN模型
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作者 曾志林 张超群 +3 位作者 吴国富 汤卫东 李灏然 李婉秋 《中文信息学报》 北大核心 2025年第2期89-99,110,共12页
在社交网络中,大多数节点的数据不完整,已有的方法对这些节点的预测效率较低。鉴于此,该文提出一种融合影响力最大化的知识可迁移图神络网络(Graph Neural Network,GNN)模型VRKTGNN,其是对预测社交网络未知节点的KTGNN模型的改进。VRKT... 在社交网络中,大多数节点的数据不完整,已有的方法对这些节点的预测效率较低。鉴于此,该文提出一种融合影响力最大化的知识可迁移图神络网络(Graph Neural Network,GNN)模型VRKTGNN,其是对预测社交网络未知节点的KTGNN模型的改进。VRKTGNN根据用户的关注去构建一个图结构数据,由改进的投票排名算法VoteRank++选出图数据中影响力最大的节点对未知节点进行知识迁移,通过KTGNN利用影响力最大的节点将未知节点的信息进行完善或者补全,进而预测出大多数未知节点的一个关注重点。在五个数据集上的实验结果表明,VRKTGNN总体明显优于十个对比模型。具体来说,与最优的对比模型KTGNN相比,VRKTGNN在Github-web数据集上性能非常接近,而在Twitch-DE、Tolokers、Twitter、Twitch-EN数据集上的F_(1)值分别提升5.73%、2.9%、2.86%和1.83%。这些结果均表明,该文新提出的模型鲁棒性更强,能够利用影响力最大的节点对社交网络中的未知节点进行有效预测,且对复杂网络更具优势。 展开更多
关键词 社交网络 影响力最大化 图神经网络 知识迁移
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具有网络结构适应性的社交网络影响最大化方法
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作者 汪晓洁 侯小静 +1 位作者 徐春 张蕾 《计算机工程与科学》 北大核心 2025年第4期667-676,共10页
影响最大化在社交网络分析和挖掘中得到了广泛的研究,其目的是找到一个具有k个节点的种子集合,使得该节点集合在某种传播模型下影响传播的范围最大。现有研究鲜有考虑网络结构对信息传播的影响,影响最大化算法通常对不同结构类型的网络... 影响最大化在社交网络分析和挖掘中得到了广泛的研究,其目的是找到一个具有k个节点的种子集合,使得该节点集合在某种传播模型下影响传播的范围最大。现有研究鲜有考虑网络结构对信息传播的影响,影响最大化算法通常对不同结构类型的网络适应性不强。针对该问题,研究了具有网络结构适应性的影响最大化问题,分析了网络结构对影响传播产生的影响。针对二者的影响关系,提出了3种分配策略以适应不同的网络类型;然后,在社区尺度上对节点影响力进行度量,构建初始种子节点集合;最后,对初始种子节点集合进行调优,进一步提高种子节点的质量。在具有不同结构的真实数据集和合成数据集上的实验表明,提出的算法在各项性能指标上均取得了较好的效果,发现了影响传播与种子节点间的平均距离之间,并不是种子节点间的距离越大,影响传播越好,这改变了在考虑传播重叠问题时对种子节点间平均距离的固有认知。 展开更多
关键词 社交网络 影响最大化 网络适应性 分配策略 社区结构
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网络扩散中迭代产品的退市时机与投放种子优化
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作者 熊澳 翁克瑞 《系统管理学报》 北大核心 2025年第1期40-49,共10页
科技上的不断创新提高了企业产品推陈出新的速度。在新产品发布时,新产品与旧产品之间存在内部竞争关系,企业需要考虑以下两个问题:一是新产品如何投放,以快速渗透市场;二是旧产品是否即时退市,以为新产品提供更大的市场空间。研究了产... 科技上的不断创新提高了企业产品推陈出新的速度。在新产品发布时,新产品与旧产品之间存在内部竞争关系,企业需要考虑以下两个问题:一是新产品如何投放,以快速渗透市场;二是旧产品是否即时退市,以为新产品提供更大的市场空间。研究了产品迭代时退市时机与投放种子选择问题:在一个已存在旧产品的社会网络G(N,E)中投放新产品,新旧产品以内部竞争的扩散机制传播其影响力,如何选择旧产品退市时机与新产品投放种子,使得新旧产品的扩散利润最大化。建立了该问题的整数规划模型,刻画了考虑内部竞争的影响力扩散过程,设计了退市时机与种子选择迭代更新的混合贪婪算法(IUHGA)。与经典算法的对比实验显示,IUHGA具有较高的求解质量。研究结果表明:旧产品退市时机与更新产品利润、种子数量、产品最大扩散周期和网络用户聚集度存在一定关系。 展开更多
关键词 社会网络 影响力最大化 产品迭代 退市时机
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IMVis: Visual analytics for influence maximization algorithm evaluation in hypergraphs
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作者 Jin Xu Chaojian Zhang +4 位作者 Ming Xie Xiuxiu Zhan Luwang Yan Yubo Tao Zhigeng Pan 《Visual Informatics》 EI 2024年第2期13-26,共14页
Influence maximization(IM)algorithms play a significant role in hypergraph analysis tasks,such as epidemic control analysis,viral marketing,and social influence analysis,and various IM algorithms have been proposed.Th... Influence maximization(IM)algorithms play a significant role in hypergraph analysis tasks,such as epidemic control analysis,viral marketing,and social influence analysis,and various IM algorithms have been proposed.The main challenge lies in IM algorithm evaluation,due to the complexity and diversity of the spreading processes of different IM algorithms in different hypergraphs.Existing evaluation methods mainly leverage statistical metrics,such as influence spread,to quantify overall performance,but do not fully unravel spreading characteristics and patterns.In this paper,we propose an exploratory visual analytics system,IMVis,to assist users in exploring and evaluating IM algorithms at the overview,pattern,and node levels.A spreading pattern mining method is first proposed to characterize spreading processes and extract important spreading patterns to facilitate efficient analysis and comparison of IM algorithms.Novel visualization glyphs are designed to comprehensively reveal both temporal and structural features of IM algorithms’spreading processes in hypergraphs at multiple levels.The effectiveness and usefulness of IMVis are demonstrated through two case studies and expert interviews. 展开更多
关键词 influence maximization evaluation Comparative visual analysis Visual analytics
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基于IMS的IPTV架构及其对IMS网络架构的影响分析 被引量:4
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作者 张茜 王亚晨 赵耀 《电信科学》 北大核心 2009年第9期68-73,共6页
在电信网、广播电视网、互联网三网融合的趋势下,基于IMS网络提供IPTV业务是IPTV近年来的主要发展方向之一。各国际标准化组织已经进行了较为深入的研究工作。本文首先介绍各标准化组织的相关研究进展,而后针对IPTV业务的特点,在国际标... 在电信网、广播电视网、互联网三网融合的趋势下,基于IMS网络提供IPTV业务是IPTV近年来的主要发展方向之一。各国际标准化组织已经进行了较为深入的研究工作。本文首先介绍各标准化组织的相关研究进展,而后针对IPTV业务的特点,在国际标准化组织研究基础上提出基于IMS的IPTV体系架构并进行分析,最后着重分析IPTV业务对IMS网络的影响。 展开更多
关键词 imS IPTV 系统架构 业务 影响
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Identifying influential nodes in social networks via community structure and influence distribution difference 被引量:3
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作者 Zufan Zhang Xieliang Li Chenquan Gan 《Digital Communications and Networks》 SCIE CSCD 2021年第1期131-139,共9页
This paper aims to effectively solve the problem of the influence maximization in social networks.For this purpose,an influence maximization method that can identify influential nodes via the community structure and t... This paper aims to effectively solve the problem of the influence maximization in social networks.For this purpose,an influence maximization method that can identify influential nodes via the community structure and the influence distribution difference is proposed.Firstly,the network embedding-based community detection approach is developed,by which the social network is divided into several high-quality communities.Secondly,the solution of influence maximization is composed of the candidate stage and the greedy stage.The candidate stage is to select candidate nodes from the interior and the boundary of each community using a heuristic algorithm,and the greedy stage is to determine seed nodes with the largest marginal influence increment from the candidate set through the sub-modular property-based Greedy algorithm.Finally,experimental results demonstrate the superiority of the proposed method compared with existing methods,from which one can further find that our work can achieve a good tradeoff between the influence spread and the running time. 展开更多
关键词 Social network Community detection influence maximization Network embedding influence distribution difference
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Influence Diffusion Model in Multiplex Networks
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作者 Senbo Chen Wenan Tan 《Computers, Materials & Continua》 SCIE EI 2020年第7期345-358,共14页
The problem of influence maximizing in social networks refers to obtaining a set of nodes of a specified size under a specific propagation model so that the aggregation of the node-set in the network has the greatest ... The problem of influence maximizing in social networks refers to obtaining a set of nodes of a specified size under a specific propagation model so that the aggregation of the node-set in the network has the greatest influence.Up to now,most of the research has tended to focus on monolayer network rather than on multiplex networks.But in the real world,most individuals usually exist in multiplex networks.Multiplex networks are substantially different as compared with those of a monolayer network.In this paper,we integrate the multi-relationship of agents in multiplex networks by considering the existing and relevant correlations in each layer of relationships and study the problem of unbalanced distribution between various relationships.Meanwhile,we measure the distribution across the network by the similarity of the links in the different relationship layers and establish a unified propagation model.After that,place on the established multiplex network propagation model,we propose a basic greedy algorithm on it.To reduce complexity,we combine some of the characteristics of triggering model into our algorithm.Then we propose a novel MNStaticGreedy algorithm which is based on the efficiency and scalability of the StaticGreedy algorithm.Our experiments show that the novel model and algorithm are effective,efficient and adaptable. 展开更多
关键词 StaticGreedy social networks influence maximization multiplex networks
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基于不完美信道估计的闭环MIMO-MRC跨层设计
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作者 徐龙泉 王富强 《信息通信》 2015年第5期1-3,共3页
为提高无线通信的频谱效率,提出一种MIMO-MRC(multiple-input multiple-output-maximal ratio combining)跨层方案。是物理层的自适应调制(adaptive modulation,AM)和数据链路层的自动重传(automatic repeat request,ARQ)协作,发射端利... 为提高无线通信的频谱效率,提出一种MIMO-MRC(multiple-input multiple-output-maximal ratio combining)跨层方案。是物理层的自适应调制(adaptive modulation,AM)和数据链路层的自动重传(automatic repeat request,ARQ)协作,发射端利用估计信道信息反馈,自适应调节调制模式,选择最优发射权矢量和自动重传发射数据。分析了估计误差对MIMO-MRC跨层系统的影响,给出了MIMO-MRC系统在信道估计存在误差时的频谱效率和中断概率的闭合表达式。通过仿真实验证明,对比SISO(single-input single-output)跨层系统和A lamouti's跨层系统,MIMO-MRC跨层系统的性能有明显提高,可获得约3 d B的分集增益。 展开更多
关键词 跨层设计 自适应调制 自动重传 最大比合并 不完美信道估计
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基于Transformer模型的社交网络影响力最大化算法
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作者 于树科 姚瑶 严晨雪 《电信科学》 北大核心 2024年第12期114-124,共11页
基于网络拓扑结构的社交网络影响力最大化算法受网络结构影响大,导致在不同规模、不同拓扑结构的社交网络上的性能不稳定。针对此问题,提出一种基于改进Transformer模型的社交网络影响力最大化算法。首先,基于K-shell分解法筛选社交网... 基于网络拓扑结构的社交网络影响力最大化算法受网络结构影响大,导致在不同规模、不同拓扑结构的社交网络上的性能不稳定。针对此问题,提出一种基于改进Transformer模型的社交网络影响力最大化算法。首先,基于K-shell分解法筛选社交网络中影响力高的节点;然后,运用随机游走策略发现候选节点的拓扑结构信息和连接框架信息;最终,对Transformer模型进行改进,使其支持可扩展的节点特征序列,利用改进Transformer模型预测社交网络中的种子节点。在6个不同规模的真实社交网络上完成了验证实验。结果表明,所提算法在不同规模、不同拓扑结构的社交网络上均实现了较好的影响力最大化性能,且大幅提高了种子节点识别的时间效率。 展开更多
关键词 社交网络 影响力节点 影响力最大化 信息传播 神经网络
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红花椒风味品质的影响因素研究 被引量:4
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作者 梁琪 祝磊 +3 位作者 张婷 王静雯 钟慈平 吴纯洁 《中国调味品》 CAS 北大核心 2024年第1期48-52,66,共6页
目的:考察温度、光照、氧气3个因素对红花椒风味物质的综合影响。方法:采用HPLC测定不同影响因素下花椒中羟基-α-山椒素、羟基-β-山椒素、羟基-γ-山椒素、羟基-ε-山椒素等麻味物质含量;采用GC测定不同影响因素下花椒中芳樟醇、柠檬... 目的:考察温度、光照、氧气3个因素对红花椒风味物质的综合影响。方法:采用HPLC测定不同影响因素下花椒中羟基-α-山椒素、羟基-β-山椒素、羟基-γ-山椒素、羟基-ε-山椒素等麻味物质含量;采用GC测定不同影响因素下花椒中芳樟醇、柠檬烯、乙酸芳樟酯等香味物质含量;采用极坐标对不同因素对风味物质的影响进行综合强度分析。结果:4℃和25℃时麻味物质含量高且差异较小,4℃时香味物质含量最高;遮光条件下麻味和香味物质含量保存最佳;隔氧条件下,随着储存时间的延长,麻味和香味物质损失较慢;结合强度分析图得出红花椒受到影响的因素主要包括氧气、温度和光照,其中氧气对其影响最显著。结论:对红花椒风味品质的影响因素按照重要性排序为氧气>温度>光照,隔氧、遮光、4℃是最佳条件。该研究为花椒调味品加工、运输和储存提供了参考依据。 展开更多
关键词 红花椒 影响因素 麻味 香味
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独立级联传播模型下的连续影响力最大化
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作者 邓紫维 陈崚 刘维 《计算机科学》 CSCD 北大核心 2024年第6期161-171,共11页
影响力最大化是在社交网络中寻求一组最具有影响力的用户作为种子节点,通过种子节点向网络中传播信息,使得传播的范围最大化。现有的对影响力最大化的研究大多是针对每个节点,考虑是否将其作为种子节点。而在实际应用中,需要根据用户的... 影响力最大化是在社交网络中寻求一组最具有影响力的用户作为种子节点,通过种子节点向网络中传播信息,使得传播的范围最大化。现有的对影响力最大化的研究大多是针对每个节点,考虑是否将其作为种子节点。而在实际应用中,需要根据用户的影响力来赋予他成为种子的概率,使得根据这个概率分布得到的种子集合的影响力传播范围的期望值最大化,这就是连续影响力最大化问题。文中提出了一种独立级联传播模型下连续影响力最大化算法。该算法首先将上述问题抽象成一个约束优化问题,然后抽样若干个可能的种子集,并对每个可能的种子集估计影响的传播范围;使用梯度下降法,在每轮迭代中根据估计的传播范围计算各个方向的增量值,取最大增量的方向作为梯度进行目标函数值的迭代更新,从而得到目标函数值的最优解。在真实和虚拟网络上进行实验,结果表明,该算法在影响范围的期望值上优于Random,Degree,UD和CD等算法。 展开更多
关键词 连续影响力最大化 社交网络 独立级联传播模型 梯度下降 迭代
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Approximating Special Social Influence Maximization Problems 被引量:6
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作者 Jie Wu Ning Wang 《Tsinghua Science and Technology》 SCIE EI CAS CSCD 2020年第6期703-711,共9页
Social Influence Maximization Problems(SIMPs)deal with selecting k seeds in a given Online Social Network(OSN)to maximize the number of eventually-influenced users.This is done by using these seeds based on a given se... Social Influence Maximization Problems(SIMPs)deal with selecting k seeds in a given Online Social Network(OSN)to maximize the number of eventually-influenced users.This is done by using these seeds based on a given set of influence probabilities among neighbors in the OSN.Although the SIMP has been proved to be NP-hard,it has both submodular(with a natural diminishing-return)and monotone(with an increasing influenced users through propagation)that make the problem suitable for approximation solutions.However,several special SIMPs cannot be modeled as submodular or monotone functions.In this paper,we look at several conditions under which non-submodular or non-monotone functions can be handled or approximated.One is a profit-maximization SIMP where seed selection cost is included in the overall utility function,breaking the monotone property.The other is a crowd-influence SIMP where crowd influence exists in addition to individual influence,breaking the submodular property.We then review several new techniques and notions,including double-greedy algorithms and the supermodular degree,that can be used to address special SIMPs.Our main results show that for a specific SIMP model,special network structures of OSNs can help reduce its time complexity of the SIMP. 展开更多
关键词 influence maximization online social networks submodular function
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