The Effect of Key Nodes on theMalware Dynamics in the Industrial Control Network

As industrialization and informatization becomemore deeply intertwined,industrial control networks have entered an era of intelligence.The connection between industrial control networks and the external internet is becoming increasingly close,which leads to frequent security accidents.This paper proposes a model for the industrial control network.It includes a malware containment strategy that integrates intrusion detection,quarantine,and monitoring.Basedonthismodel,the role of keynodes in the spreadofmalware is studied,a comparisonexperiment is conducted to validate the impact of the containment strategy.In addition,the dynamic behavior of the model is analyzed,the basic reproduction number is computed,and the disease-free and endemic equilibrium of the model is also obtained by the basic reproduction number.Moreover,through simulation experiments,the effectiveness of the containment strategy is validated,the influence of the relevant parameters is analyzed,and the containment strategy is optimized.In otherwords,selective immunity to key nodes can effectively suppress the spread ofmalware andmaintain the stability of industrial control systems.The earlier the immunization of key nodes,the better.Once the time exceeds the threshold,immunizing key nodes is almost ineffective.The analysis provides a better way to contain the malware in the industrial control network.

RESEARCH ON KEY NODES OF WIRELESS SENSOR NETWORK BASED ON COMPLEX NETWORK THEORY

On the basis of complex network theory, the issues of key nodes in Wireless Sensor Networks (WSN) are discussed. A model expression of sub-network fault in WSN is given at first; subsequently, the concepts of average path length and clustering coefficient are introduced. Based on the two concepts, a novel attribute description of key nodes related to sub-networks is proposed. Moreover, in terms of node deployment density and transmission range, the concept of single-point key nodes and generalized key nodes of WSN are defined, and their decision theorems are investigated.

Improved Key Node Recognition Method of Social Network Based on PageRank Algorithm

The types and functions of social networking sites are becoming more abundant with the prevalence of self-media culture,and the number of daily active users of social networking sites represented by Weibo and Zhihu continues to expand.There are key node users in social networks.Compared with ordinary users,their influence is greater,their radiation range is wider,and their information transmission capabilities are better.The key node users playimportant roles in public opinion monitoring and hot event prediction when evaluating the criticality of nodes in social networking sites.In order to solve the problems of incomplete evaluation factors,poor recognition rate and low accuracy of key nodes of social networking sites,this paper establishes a social networking site key node recognition algorithm(SNSKNIS)based on PageRank(PR)algorithm,and evaluates the importance of social networking site nodes in combination with the influence of nodes and the structure of nodes in social networks.This article takes the Sina Weibo platform as an example,uses the key node identification algorithm system of social networking sites to discover the key nodes in the social network,analyzes its importance in the social network,and displays it visually.

Identification of key recovering node for spatial networks

Many networks in the real world have spatial attributes, such as location of nodes and length of edges, called spatial networks. When these networks are subject to some random or deliberate attacks, some nodes in the network fail, which causes a decline in the network performance. In order to make the network run normally, some of the failed nodes must be recovered. In the case of limited recovery resources, an effective key node identification method can find the key recovering node in the failed nodes, by which the network performance can be recovered most of the failed nodes. We propose two key recovering node identification methods for spatial networks, which are the Euclidean-distance recovery method and the route-length recovery method. Simulations on homogeneous and heterogeneous spatial networks show that the proposed methods can significantly recover the network performance.

Analysis of identification methods of key nodes in transportation network

The identification of key nodes plays an important role in improving the robustness of the transportation network.For different types of transportation networks,the effect of the same identification method may be different.It is of practical significance to study the key nodes identification methods corresponding to various types of transportation networks.Based on the knowledge of complex networks,the metro networks and the bus networks are selected as the objects,and the key nodes are identified by the node degree identification method,the neighbor node degree identification method,the weighted k-shell degree neighborhood identification method(KSD),the degree k-shell identification method(DKS),and the degree k-shell neighborhood identification method(DKSN).Take the network efficiency and the largest connected subgraph as the effective indicators.The results show that the KSD identification method that comprehensively considers the elements has the best recognition effect and has certain practical significance.

Key Technologies of Wireless Heterogeneous Network Security

Convergence and collaboration of heterogeneous networks in the next generation public mobile networks will be a subject of universal significance. Convergence of heterogeneous networks, as an effective approach to improve the coverage and capacity of public mobile network, to enable communication services, to provide Internet access and to enable mobile computing from everywhere, has drawn widespread attention for its good prospects in application. Construction of security system for wireless heterogeneous networks and development of new security models, key security techniques and approaches are critical and mandatory in heterogeneous networks development. Key technology of wireless heterogeneous networks security covers security routing protocol, access authentication, intrusion detection system, cooperative communication between nodes, etc.

Application Independent Dynamic Group-Based Key Establishment for Large-scale Wireless Sensor Networks

Key establishment and its management in Wireless Sensor Networks(WSN) is a challenging problem due to its limited resources and disordered structure. Many key management schemes have been developed recently for WSN to provide secure communication between source and destination sensor nodes.A serious threat highlighted in all of these schemes is that of node capture attacks,where an adversary gains full control over a sensor node through direct physical access.Node capture attacks can also be helpful to an adversary in new attacks like Blackhole and Denial of Service.All of these proposed key management solutions still suffer from node capture attacks with resilience.The current sensor networks are assumed to be designed for specific applications,having key management protocols strongly coupled to applications.The future sensor networks are envisioned as comprising heterogeneous devices assisting to a large range of applications.To achieve this goal,a new application independent approach is needed. In this paper we therefore present a novel,extended version of our previously published Dynamic Group-based Key Establishment(DGKE) protocol. We compare the proposed scheme with existing key management schemes,which shows a significant improvement in resilience against node capture attacks,memory overhead and connectivity.

Complex Network Formation and Analysis of Online Social Media Systems

To discover and identify the influential nodes in any complex network has been an important issue.It is a significant factor in order to control over the network.Through control on a network,any information can be spread and stopped in a short span of time.Both targets can be achieved,since network of information can be extended and as well destroyed.So,information spread and community formation have become one of the most crucial issues in the world of SNA(Social Network Analysis).In this work,the complex network of twitter social network has been formalized and results are analyzed.For this purpose,different network metrics have been utilized.Visualization of the network is provided in its original form and then filter out(different percentages)from the network to eliminate the less impacting nodes and edges for better analysis.This network is analyzed according to different centrality measures,like edge-betweenness,betweenness centrality,closeness centrality and eigenvector centrality.Influential nodes are detected and their impact is observed on the network.The communities are analyzed in terms of network coverage considering theMinimum Spanning Tree,shortest path distribution and network diameter.It is found that these are the very effective ways to find influential and central nodes from such big social networks like Facebook,Instagram,Twitter,LinkedIn,etc.

Research on Accurate Information Pushing Based on Human Network

Based on the social network analysis methods and human network, this paper randomly selected 44 students (31 males and 13 females) as the research objects, and it used the UCINET software to analyze the friendship between them of which 43 used WeChat and 44 used QQ, and it also used the tool Netdraw to visualize the network sociogram. By mining the four aspects of density, accessibility, centrality, block model, the results demonstrated that QQ social network and WeChat social network existed the phenomenon of small world, leaders and subgroups, and the key nodes of QQ human network were more than WeChat network. Through using the key nodes, it can push the precise and efficient information and improve the accuracy of information transmission and impact among network members.

配电网多类型分布式资源辅助主网关键节点黑启动方案与实时调度策略

随着高比例分布式资源不断接入配电网,充分利用多类型分布式资源的黑启动价值,使配电网系统向上支撑主网关键节点快速恢复成为可能。对此,提出了配电网多类型分布式资源辅助主网关键节点黑启动方案与实时调度策略。首先,分析配电网系统支撑主网关键节点黑启动的优势及其可行性。然后,针对节点启动顺序与恢复路径互为驱动、相互支撑特征,以最大配电网系统可用发电容量、最小配电网内重要负荷损失量和最小恢复路径权值为目标建立主网关键节点与配电网内重要负荷协同恢复的优化模型,并采用遗传算法与弗洛伊德算法相结合的方法求解,提出一种基于滚动优化模型的黑启动实时调度策略,以确保主网关键节点处电源在最短时间内安全稳定恢复。最后,以某地区35节点主配网分区系统为例开展仿真分析,结果表明,所提模型和方法显著降低了主网电源节点恢复时间,有效提升电网韧性和分布式资源利用效率。

Vulnerability analysis for airport networks based on fuzzy soft sets: From the structural and functional perspective

Abstract Recently, much attention has been paid to the reliability and vulnerability of critical infrastructure. In air traffic systems, the vulnerability analysis for airport networks can be used to guide air traffic administrations in their prioritization of the maintenance and repair of airports, as well as to avoid unnecessary disturbances in the planning of flight schedules. In this paper, the evaluation methods of airport importance and network efficiency arc established. Firstly, the evaluation indices of airport importance are proposed from both the topological and functional perspectives. The topological characteristics come from the structure of airport network and the functional features stem from the traffic flow distribution taking place inside the network. Secondly, an integrated evaluation method based on fuzzy soft set theory is proposed to identify the key airports, which can fuse together importance indices over different time intervals. Thirdly, an airport network efficiency method is established for the purpose of assessing the accuracy of the evaluation method. Finally, empirical studies using real traffic data of US and China＇s airport networks show that the evaluation method proposed in this papcr is the most accuratc. Thc vulucrability of US and China＇s airport networks is compared. The similarities and differences between airport geography distribution and airport importance distribution are discussed here and the dynamics of airport importance is studied as well.

基于多节点热网络法的航空发动机主轴轴承温度场分析

航空发动机主轴轴承温度场分析是发动机润滑系统热分析的关键。针对传统简单节点热网络法中轴承温度节点设置过于简化、人为设置轴承生热分配比例等问题,提出改进的多节点热网络法。基于Hertz热扩散理论,将轴承三元件分别划分为接触表面与主体两个节点,并以Hertz扩散热阻连接;轴承接触区设置油膜节点,加载轴承生热载荷,节点与轴承接触面之间通过油膜热阻连接;构建多节点轴承热网络模型,获得轴承内部更细致的温度场分布。研究表明,轴承表面温度显著高于其内部主体结构温度,而接触区对应的两个接触面之间也存在明显的温度差异,使用本文建立的多节点热网络法对滑油出口温度的计算误差不超过7%。

基于引文网络主路径的移动图书馆研究脉络演化

掌握移动图书馆领域研究的知识演化和扩散指导国内相关研究,对移动图书馆领域引文网络实施断层扫描,了解文献之间的引证关系及引文网络路径已受到业界的关注。为此,运用Hist Cite探测不同节点规模引文网络的引证子群,确定引文网络主路径。借助Pajek的3种主路径算法分析不同节点规模的主路径成分差异,发现核心文献集和关键知识节点。通过对移动图书馆领域核心文献集及其关系的分析,揭示了移动图书馆领域知识演化的主体脉络。以此为基础,结合国内研究成果对移动图书馆创新研究主路径进行了规划。

基于有限单元热网络法的航空发动机主轴轴承热分析

航空发动机主轴轴承温度场的精准预测对保证发动机润滑系统及整机稳定运转至关重要。针对传统热网络法精度低的问题,提出一种基于有限单元思想的有限单元热网络法。将轴承结构通过网格划分为有限个单元体,每个单元体设置一个温度节点代表该单元体的集总参数,节点间构建热阻关系并形成热网络,通过求解以温度为未知量的大型稀疏矩阵线性方程组来获得滚子轴承横截面的温度分布。该方法可以与轴承局部产热理论相结合,实现轴承局部产热的精准加载,完成温度场的精细化分析。通过与试验结果对比,本文方法对轴承外环表面中心线温度的预测结果与试验结果误差不超过13%。

Finding Key Node Sets in Complex Networks Based on Improved Discrete Fireworks Algorithm

Finding out the key node sets that affect network robustness has great practical significance for network protection and network disintegration.In this paper,the problem of finding key node sets in complex networks is defined firstly.Because it is an NP-hard combinatorial optimization problem,discrete fireworks algorithm is introduced to search the optimal solution,which is a swarm intelligence algorithm and is improved by the prior information of networks.To verify the effect of improved discrete fireworks algorithm(IDFA),experiments are carried out on various model networks and real power grid.Results show that the proposed IDFA is obviously superior to the benchmark algorithms,and networks suffer more damage when the key node sets obtained by IDFA are removed from the networks.The key node sets found by IDFA contain a large number of non-central nodes,which provides the authors a new perspective that the seemingly insignificant nodes may also have an important impact on the robustness of the network.

基于图形化主接线图的电气连通性分析和研究

电气元件的连通性判别是图形化分析的基础,从主接线图中各电气元件之间的连接性及其属性之间的匹配性入手,综合分析了元件连通性的判别方法。通过把母线/开关和接地点/变压器描述的物理模型转化为节点/支路描述的网络模型,提出了分序网图分别进行电气连通性分析的新思路,这种方法对序分量及序网分析有重要指导意义。同时,结合图论方法和网络模型,通过比较已有的分析方法,改进了节点矩阵法的计算流程,使它在运算次数上大大减少,计算速度也明显提高。

试论农产品物流组织网络构建——以山东省为例

文章主要关注的是农产品物流组织网络构建的问题,以山东省为例在宏观层面以城市为对象分析比较各城市农产品物流综合水平,选择确定合理的物流结点建设物流园区;微观层面建立各物流主体的联系,形成不同的微观物流主体运作模式,使各模式与各级物流结点相配合,构成一个整体协调高效的农产品物流组织网络。

An Energy-Efficient Query Based on Variable Region for Large-Scale Smart Grid

The state-of-the-art query techniques in power grid monitoring systems focus on querying history data, which typically introduces an unwanted lag when the systems try to discover emergency situations. The monitoring data of large-scale smart grids are massive, dynamic and highly dimensional, so global query, the method widely adopted in continuous queries in Wireless Sensor Networks(WSN), is rendered not suitable for its high energy consumption. The situation is even worse with increasing application complexity. We propose an energy-efficient query technique for large-scale smart grids based on variable regions. This method can query an arbitrary region based on variable physical windows, and optimizes data retrieve paths by a key nodes selection strategy. According to the characteristics of sensing data, we introduce an efficient filter into the each query subtree to keep non-skyline data from being retrieved. Experimental results show that our method can efficiently return the overview situation of any query region. Compared to TAG and ESA, the average query efficiency of our approach is improved by 79% and 46%, respectively; the total energy consumption of regional query is decreased by 82% and 50%, respectively.

SAC-TA: A Secure Area Based Clustering for Data Aggregation Using Traffic Analysis in WSN

Clustering is the most significant task characterized in Wireless Sensor Networks (WSN) by data aggregation through each Cluster Head (CH). This leads to the reduction in the traffic cost. Due to the deployment of the WSN in the remote and hostile environments for the transmission of the sensitive information, the sensor nodes are more prone to the false data injection attacks. To overcome these existing issues and enhance the network security, this paper proposes a Secure Area based Clustering approach for data aggregation using Traffic Analysis (SAC-TA) in WSN. Here, the sensor network is clustered into small clusters, such that each cluster has a CH to manage and gather the information from the normal sensor nodes. The CH is selected based on the predefined time slot, cluster center, and highest residual energy. The gathered data are validated based on the traffic analysis and One-time Key Generation procedures to identify the malicious nodes on the route. It helps to provide a secure data gathering process with improved energy efficiency. The performance of the proposed approach is compared with the existing Secure Data Aggregation Technique (SDAT). The proposed SAC-TA yields lower average energy consumption rate, lower end-to-end delay, higher average residual energy, higher data aggregation accuracy and false data detection rate than the existing technique.

基于信任匹配机制的WSN主备节点更新算法

在无线传感器网络(WNS)的分区过程中,主备节点的更新过于频繁,使得网络传输的稳定性受到影响。为此,从减少WSN网络主备节点更新频率、强化网络传输稳定性的角度出发,提出了一种基于信任匹配机制的WSN主备节点更新算法。首先,引入聚类机制并结合剩余能量、拉氏距离、最短跳数等参数,建立基于动态维度判决方法的信任匹配机制,以减少单因素条件下节点主备轮询异常的情形,改善节点受限状况,优化主备节点的存活质量。随后,针对一次更新过程中匹配性不强的问题,引入排序机制,建立基于双重匹配的节点更新机制,从备用节点中筛选出待更新节点,优先用于监控区域节点能量数据传输,进一步降低区域能量消耗水平。与当前广泛使用的基于簇的无线传感器网络能量消耗最小化算法(CBA-E算法)、基于提高无线传感器网络生存期机制的改进簇路由协议算法(IIL算法)相比,此WSN主备节点更新算法对节点更新频率和网络传输性能的改善效果显著。