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1.
孙茜雅 《电子科技》2012,25(3):13-16,20
提出一种基于最小熵的社团结构检测算法。首先用模糊关系表示交互网络,一种基于熵的测度来确定模糊关系的隶属度,且熵越小,节点越相似。然后提出一种新的模糊关系合成规则,通过应用该规则,模糊关系被转换为最小关系。最后,通过熵的值把这个最小模糊关系划分成一个个社团。在人工网络与真实网络中的测试结果表明,该算法可以有效地识别社团结构。  相似文献   

2.
汪林玉  谷科  余飞  尹波  廖年冬 《电子学报》2019,47(4):886-895
个人意愿对于形成网络社团和传播信息有着重要的影响力,因此本文提出一种基于个人意愿的社团结构与信息检测方案.该方案中的社团检测算法初次检测以融入节点属性的模块度,再次检测以兴趣度并能发现重叠社团,最后精细检测以个人意愿,本文社团检测算法(ε_CSDA)较之前的算法更有效的是可以发现重叠社团;同时,该方案建立的信息传播模型在指数模型基础上构建边特征向量(边属性)、节点特征向量(节点属性)和意愿向量(用户意愿、社团意愿和节点意愿),并以传播概率和传播延迟构建模型基本关系,从而使得该模型实现了基于个人意愿的信息传播.实验结果表明,加入个人意愿的社团检测和信息传播方案,能够保证社团检测的有效性和实用性,能够实现用户间信息传播的主动性和可靠性.  相似文献   

3.
基于加权内容-结构网络和随机游走的社团划分算法   总被引:1,自引:0,他引:1       下载免费PDF全文
牛新征  牛嘉郡  苏大壮  佘堃 《电子学报》2017,45(9):2135-2142
针对传统模块优化社团划分算法仅能利用网络的结构信息,而无法利用同样丰富的内容信息,导致划分精度较低的问题,提出一种结合内容属性并通过给连边加权来全面优化网络拓扑结构的社团划分算法CCSRW(Classification with Content-Structure and Random Walk).设计利用随机游走理论计算结构节点与内容节点间的相似性关系矩阵,并将结构节点映射到内容属性空间上,最终把社团划分问题转化为多维无监督聚类问题.通过在真实数据集上进行的全面实验分析,展示了相比于传统社团划分算法,本文的算法能更准确的描述网络结构,显著提高划分性能,并有效解决小社团不敏感问题,更适用于大规模复杂信息网络的社团划分.  相似文献   

4.
邓小龙  温颖 《电子学报》2016,44(9):2114-2120
社团结构划分对于分析复杂网络的统计特性非常重要.在非均匀社交网络的信息传播中,社团结构划分更是一个广泛关注的研究热点,相关研究往往侧重于研究紧密连接的社团结构对于信息传播所产生的关键影响.传统社团划分方法大多基于点和边的相关特性进行构建,如标签传播算法LPA(Label Propagation Algorithm)通过半监督机器学习方法,基于网络节点标签的智能交换和社团融合过程进行社团划分,但运行效率较低.为提高LPA类算法的运行速度,使其快速收敛,并提高社团划分精度,特别是重叠社团划分精度,针对LPA算法划分中的低运行效率和低融合收敛速度,本文从标签传播的网络连接矩阵本质出发,将该矩阵的最大非零特征值与网络标签信息传播的阀值相结合,提出了新的基于传染病传播模型的社团划分方法(简称ESLPA算法,Epidemic Spreading LPA).通过经典LFR Benchmark模拟测试网络、随机网络以及真实社交网络数据上的算法验证,结果表明该算法时间复杂度大幅优于经典LPA算法,在重叠社团划分上精确度优于基于LPA模型的经典COPRA算法,特别是在重叠社团较明显时,划分精度接近精度较高GA、N-cut和A-cut算法,明显优于GN、FastGN和CPM等经典算法.  相似文献   

5.
传感器网络的路由协议越来越引起人们的关注。针对节点高密度部署并且存在部分移动节点的网络环境,当前常用的各类路由算法都不能有效地降低能耗。论文提出了改进型GAF算法,将网络划分成若干个单元格,不同移动速度的节点以不同的权重竞选簇头,竞选失败者将进入休眠状态,以此来降低网络总能耗。通过分析和仿真,验证了该算法在节能方面的优势。  相似文献   

6.
针对广域网中节点数量多,范围广的特点,提出了一种将节点划分成域,并以带宽、时延作为服务质量(QoS)指标在域间寻找可行路径的路由方案。该方案由两个算法组成,它们在把真实网络映射成为具有分级结构图的同时给出了满足服务质量要求的可行路径。  相似文献   

7.
在无线传感器网络中,基于分簇的路由协议对提高网络的寿命有着重要作用,LEACH是一种应用比较广泛的层次路由协议。本文提出一种新的基于最优分簇的无线传感器网络分簇路由(LEACH-O)算法,在簇的形成过程考虑到节点的集中程度和节点的剩余能量,从而减少传感器节点的能量消耗,优化资源利用率。仿真实表明,与传统的LEACH算法相比,该算法配传感器节点间数据传输提供了高效路由,从而延长网络的生命周期。  相似文献   

8.
通信网络宏观可靠性指标的全代数化算法   总被引:6,自引:0,他引:6  
为了更全面和客观地评价宽带大容量通信网络的可靠性能,引入宏观可靠性指标--总容量归一化加权可靠性指标概念,它是把通信容量和链路可靠性参数有机地综合在一起的指标.解决该指标全代数化计算的关键问题是寻找能够算出网络各节点之间全部路由的代数化路由算法.研究出一种逻辑代数化网络路由算法,n个节点的网络只需n次矩阵变换运算,就能得到任意节点之间的全部路由.基于新路由算法研究出网络可靠性指标的全代数化算法,它易于编写程序,利用计算机可以很方便地算出通信网络的可靠性指标,解决了总容量归一化加权可靠性指标计算困难问题,且达到实用化程度.利用算例验证了算法的正确性,并对算法的各计算过程进行了详细说明.  相似文献   

9.
石雷  韩江洪  石怡  魏振春 《通信学报》2014,35(12):11-97
在多跳多基站无线网络环境下,设计了一种基于干扰管理的高容量跨层优化策略。算法的物理层采用串行干扰消除实现干扰管理,在上层首先通过Voronoi图实现区域划分,然后基于节点的最小跳数建立每个节点到基站的初始链路分配和多跳路由方案,之后通过多时间片分配或多跳路由的节点选取对方案进行优化,并通过迭代的方式寻找吞吐量更大的优化策略。理论分析证明了该方案具有多项式时间复杂度,仿真结果显示引入了干扰管理相关技术后,整个网络的吞吐率有2到5倍的提升。  相似文献   

10.
重叠社团在社交网络大数据中普遍存在.针对现有重叠社团挖掘算法易将重叠区域错误地划分为独立的社团且计算复杂的问题,提出了一种基于局部信息度量的快速重叠社团挖掘算法(Local information based Fast Overlapped Communities Detection,Li-FOCD).首先,为节点定义局部信息度量指标——社团连接度和邻居连接度,建模节点与社团的关系,缩小了计算范围;然后,每次并行地迭代执行缩减、扩展、去重等操作,并更新局部度量指标,通过松弛每次迭代的终止条件,发现近似最优社团集合而不是最优社团,最终算法复杂度为O(m+n).基于真实的大规模社交网络数据的试验分析表明:与当前流行的重叠社团挖掘算法相比,Li-FOCD在不损失检测质量的前提下,大幅提升了计算效率.  相似文献   

11.
Cognitive Wireless Mesh Networks (CWMN) is a novel wireless network which combines the advantage of Cognitive Radio (CR) and wireless mesh networks. CWMN can realize seamless integration of heterogeneous wireless networks and achieve better radio resource utilization. However, it is particularly vulnerable due to its features of open medium, dynamic spectrum, dynamic topology, and multi-top routing, etc.. Being a dynamic positive security strategy, intrusion detection can provide powerful safeguard to CWMN. In this paper, we introduce trust mechanism into CWMN with intrusion detection and present a trust establishment model based on intrusion detection. Node trust degree and the trust degree of data transmission channels between nodes are defined and an algorithm of calculating trust degree is given based on distributed detection of attack to networks. A channel assignment and routing scheme is proposed, in which selects the trusted nodes and allocates data channel with high trust degree for the transmission between neighbor nodes to establish a trusted route. Simulation results indicate that the scheme can vary channel allocation and routing dynamically according to network security state so as to avoid suspect nodes and unsafe channels, and improve the packet safe delivery fraction effectively.  相似文献   

12.
Recently more and more research interest focuses on the energy efficient routing in mobile ad hoc networks and many related routing algorithms are reported. In this paper, a new optimized priority based energy efficient routing algorithm is presented and priority is added to the existing routing algorithm according to the residual energy proportion of the nodes. Lower residual energy means lower priority and the nodes with lower priority are less likely to forward packets to other nodes. The algorithm needs no global information of the networks and only a little modification is needed to the existing algorithm, so it is practical to be implemented. The algorithm can improve the performance of routing discovery, routing maintenance and cache management at the same time. Some optimization strategy is taken to reduce the network overhead and the lifetime of the network is much longer and the network with our algorithm can transfer much more effective data. Simulation with NS-2 is done and satisfying results are obtained with this algorithm. The results show that the algorithm is efficient.  相似文献   

13.
Dynamic Routing and Wavelength Assignment in Survivable WDM Networks   总被引:1,自引:0,他引:1  
Dense wavelength division multiplexing (DWDM) networks are very attractive candidates for next generation optical Internet and intelligent long-haul core networks. In this paper we consider DWDM networks with wavelength routing switches enabling the dynamic establishment of lightpaths between each pair of nodes. The dynamic routing and wavelength assignment (RWA) problem is studied in multifiber networks, assuming both protection strategies: dedicated and shared. We solve the two subproblems of RWA simultaneously, in a combined way using joint methods for the wavelength selection (WS) and wavelength routing (WR) tasks. For the WS problem in contrast to existing strategies we propose a new, network state based selection method, which tries to route the demand on each wavelength, and selects the best one according to different network metrics (such as available channels, wavelengths per fiber and network load). For the WR problem we propose several weight functions for using in routing algorithms (Dijkstra or Suurballe), adapting dynamically to the load of the links and to the length of the path. The combination of different wavelength selection and routing (WS&WR) methods enables wide configuration opportunities of our proposed algorithm allowing good adaptation to any network state. We also propose the extension of the RWA algorithm for dedicated and shared protection and a new method for applying shared protection in dynamic WDM environment. The detailed analysis of the strategies demonstrate that our RWA algorithm provides significantly better performance than previous methods in terms of blocking probability whether with or without protection methods.  相似文献   

14.
容迟网络中基于节点间亲密度的分组路由方法   总被引:1,自引:0,他引:1  
借鉴MANET中通过分簇来减少冗余副本和社交网络中有关挖掘社交圈的思想,通过分析节点的移动规律,定义了基于节点间亲密度的拓扑结构,并将该亲密度在拓扑图中量化为可以比较的边的权值,依据边的权值大小进行拓扑裁剪,挖掘出相互亲密度较高的节点分组,并且针对源节点和目的节点所在的分组对spray and wait路由方法进行改进,来决定本身的报文副本的分配情况,进而提出了基于节点间亲密度的分组路由方法(PBI)。实验结果表明,该路由方法能够明显地提高投递成功率并且减小网络时延。  相似文献   

15.
Higher power relay nodes can be used as cluster heads in two-tiered sensor networks to achieve improved network lifetime. The relay nodes may form a network among themselves to route data towards the base station. In this model, the lifetime of a network is determined mainly by the lifetimes of these relay nodes. An energy-aware communication strategy can greatly extend the lifetime of such networks. However, integer linear program (ILP) formulations for optimal, energy-aware routing quickly become computationally intractable and are not suitable for practical networks. In this paper, we have proposed an efficient solution, based on a genetic algorithm (GA), for scheduling the data gathering of relay nodes, which can significantly extend the lifetime of a relay node network. For smaller networks, where the global optimum can be determined, our GA based approach is always able to find the optimal solution. Furthermore, our algorithm can easily handle large networks, where it leads to significant improvements compared to traditional routing schemes.  相似文献   

16.

Wireless sensor networks are used for low-cost unsupervised observation in a wide-range of environments and their application is largely constrained by the limited power sources of their constituent sensor nodes. Techniques such as routing and clustering are promising and can extend network lifetime significantly, however finding an optimal routing and clustering configuration is a NP-hard problem. In this paper, we present an energy efficient binary particle swarm optimization based routing and clustering algorithm using an intuitive matrix-like particle representation. We propose a novel particle update strategy and an efficient linear transfer function which outperform previously employed particle update strategies and some traditional transfer functions. Detailed experiments confirmed that our routing and clustering algorithm yields significantly higher network lifetime in comparison to existing algorithms. Furthermore, our results suggest that Binary PSO is better equipped to solve discrete problems of routing and clustering than its continuous counterpart, PSO.

  相似文献   

17.
一种新的移动Ad hoc网络的安全路由策略   总被引:3,自引:2,他引:1  
本文从各网络节点易受攻击、俘获,各网络节点之间不可信赖的角度出发,引入了可信任第三方的信任分散策略并结合Diffie-Hellman密钥交换算法,提出了一种新的移动Adhoc网络的安全路由策略。  相似文献   

18.
蔡君  余顺争 《通信学报》2013,34(4):21-179
提出一种增添能最有效减弱网络社团特性的边以提高Internet网络传输性能的策略,即减弱社团结构策略(简称WCS策略),并基于光逻辑链路可以提供与实际物理链路相当的高性能,以实现WCS策略的Internet网络的拓扑重构。在伪随机网络、具有社团结构的无标度人工网络和实际Internet网络上分别进行了基于全局最短路径路由和局部路由的实验。实验结果表明,利用WCS策略在社团之间少量边的添加,就能实现网络负载能力和平均最短路径的大幅改善。  相似文献   

19.
Because of explosive growth in Internet traffic and high complexity of heterogeneous networks,improving the routing and wavelength assignment (RWA) algorithm in underlying optical networks has become very important.Where there are multiple links between different the node pairs,a traditional wavelength-assignment algorithm may be invalid for a wavelength-switched optical networks (WSON) that has directional blocking constraints.Also,impairments in network nodes and subsequent degradation of optical signals may cause modulation failure in the optical network.In this paper,we propose an RWA algorithm based on a novel evaluation model for a WSON that has multiple constraints.The algorithm includes comprehensive evaluation model (CEM) and directional blocking constraint RWA based on CEM (DB-RWA).Diverse constraints are abstracted into various constraint conditions in order to better assign routing and wavelength.We propose using the novel CEM to optimize routing according to an assessed value of constraints on transmission performance.This eliminates the effects of physical transmission impairments in a WSON.DB-RWA based on CEM abstracts directional blocking conditions in multiple links between network nodes into directional blocking constraints.It also satisfies rigorous network specifications and provides flexibility,scalability,and first-fit rate for the backbone,especially in multiple links between WSON nodes.  相似文献   

20.
Due to uncertain network connectivity,efficiently data forwarding in Mobile social networks (MSNs) becomes challenging.To conquer the problem,an Efficient data forwarding scheme based on geography intimacy (GIDF) for MSNs to achieve higher delivery ratio is proposed.In GIDF,we firstly propose an Intimacy based dynamic community detection algorithm (IDCD),which divide the MSNs into several communities.We propose a novel metric geography intimacy which can quantify the node's geographical information and the friendships between nodes.Based on geography intimacy,we further propose a routing algorithm to forward data.Compared with the geography intimacy between nodes,the next hop is found,further find the route of data forwarding by doing the similar operations.Extensive simulations on real data with the ONE simulator show that GIDF is more efficient than the existing algorithms.  相似文献   

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