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Game-theoretical Model for Dynamic Defense Resource Allocation in Cyber-physical Power Systems Under Distributed Denial of Service Attacks

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Journal of Modern Power Systems and Clean Energy 2024年第1期12卷 41-51页

作者： Bingjing Yan Pengchao Yao Tao Yang boyang zhou Qiang Yang the College of Electrical Engineering Zhejiang UniversityHangzhou 310027China Zhejiang Lab Hangzhou 311100China

Electric power grids are evolving into complex cyber-physical power systems(CPPSs)that integrate advanced information and communication technologies(ICTs)but face increasing cyberspace threats and *** study considers CPPS cyberspace security under distributed denial of service(DDoS)attacks and proposes a nonzero-sum game-theoretical model with incomplete information for appropriate allocation of defense resources based on the availability of limited *** time delay is applied to quantify the expected utility as CPPSs have high time requirements and incur massive damage DDoS *** resource allocation strategies are adopted by attackers and defenders under the three cases of attack-free,failed attack,and successful attack,which lead to a corresponding consumption of resources.A multidimensional node value analysis is designed to introduce physical and cybersecurity *** experiments and numerical results demonstrate the effectiveness of the proposed model for the appropriate allocation of defense resources in CPPSs under limited resource availability.

关键词： Game theory complex cyber-physical power system(CPPS) multidimensional evaluation distributed denial of service(DDoS)attack

Safe Reconfiguring Data Plane via Supervision over Resource and Flow States

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Chinese Journal of Electronics 2015年第3期24卷 642-647页

作者： GAO Wen zhou boyang WU Chunming zhou Haifeng JIANG Ming HONG Xiaoyan College of Computer Science Zhejiang University Institute of Soft. and Intelli. Tech. Hangzhou Dianzi University Department of Computer Science University of Alabama

In the Software-defined networking(SDN),when multiple control domains are used in control services,the transient state problem can occur causing the service flow interruption when border switches are updated asynchronously. We analyze the uniqueness of this problem for SDN, and propose a light-weight protocol for safe reconfiguration of the border switches in order to improve the availability of the services running in SDN. Our solution is designed as a generic supervision layer added in the control plane to support different types of services. To demonstrate the benefits, we implement a prototype of Informationcentric networks(ICN) with the protocol, and conduct experiments using Planet Lab. The results show the ICN service can continuously serve high volume requests for contents despite the congestions built by the heavy background traffic. The performance gains in terms of the mean and standard deviation of the content retrieve delay are40.5% and 21.56%.

关键词： Software-defined networking Network architecture Network management

Variational quality control of non-Gaussian innovations and its parametric optimizations for the GRAPES m3DVAR system

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Frontiers of Earth Science 2023年第2期17卷 620-631页

作者： Jie HE Yang SHI boyang zhou Qiuping WANG Xulin MA Guangzhou Institute of Tropical and Marine Meteorology China Meteorological AdministrationGuangzhou 510640China Guangdong Meteorological Observatory Guangzhou 510640China Qingdao Air Traffic Management Station of Civil Aviation of China Qingdao 266108China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Key Laboratory of Meteorological DisasterNanjing University of Information Science and TechnologyNanjing 210044China

The magnitude and distribution of observation innovations,which have an important impact on the analyzed accuracy,are critical variables in data *** quality control(VarQC)based on the contaminated Gaussian distribution(CGD)of observation innovations is now widely used in data assimilation,owing to the more reasonable representation of the probability density function of innovations that can sufficiently absorb observations by assigning different weights ***,the inaccurate parameters prevent VarQC from showing the advantages it should have in the GRAPES(Global/Regional Assimilation and PrEdiction System)m3DVAR ***,the parameter optimization methods are considerable critical studies to improve *** this paper,we describe two probable CGDs to include the non-Gaussian distribution of actual observation errors,Gaussian plus flat distribution and Huber norm *** potential optimization methods of the parameters are introduced in detail for different *** different parameter configurations,the optimization analysis shows that the Gaussian plus flat distribution and the Huber norm distribution are more consistent with the long-tail distribution of actual innovations compared to the Gaussian *** VarQC’s cost and gradient functions with Huber norm distribution are more reasonable,while the VarQC’s cost function with Gaussian plus flat distribution may converge on different minimums due to its nonconcave *** weight functions of two VarQCs gradually decrease with the increase of innovation but show different shapes,and the VarQC with Huber norm distribution shows more elasticity to assimilate the observations with a high contamination ***,we reveal a general derivation relationship between the CGDs and VarQCs.A novel schematic interpretation that classifies the assimilated data into three categories in VarQC is *** are conducive to the development of a new Var

关键词： data assimilation variational quality control contaminated Gaussian distribution non-Gaussian distribution innovation

Multi-variant network address hopping to defend stealthy crossfire attack

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Science China(Information Sciences) 2020年第6期63卷 241-243页

作者： boyang zhou Gaoning PAN Chunming WU Kai ZHU Wei RUAN Zhejiang Lab College of Computer Science Zhejiang University College of Control Science and Engineering Zhejiang University

Dear editor,Recently, crossfire attack has been witnessed as a new distributed denial-of-service (DDoS) weapon that can effectively cut off the data connections between the chosen target area (wd) of servers and the end hosts (H). The attack is launched by a network of bot (botnet) to drain bandwidth of persistent routes (PRs) in the indirect and lowrate data flooding towards the decoys that are located in upstream to the target, where the PRs are

关键词： TTL Multi-variant network address hopping to defend stealthy crossfire attack

A Centralized Algorithm for Assigning MDC Video Application in Virtual Network

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China Communications 2016年第S1期13卷 158-166页

作者： ZHU Kai WU Chunming zhou boyang CHEN Fei WANG Haoxue Next Generation Network Laboratory College of Computer Science and Technology Zhejiang University Henan Electrical Power Research Institute State Grid Corporation of China Information Engineering University

Providing services on demand is a major contributing factor to drive the increasingly development of the software defined network. However, it should supply all the current popular applications before it really attains widespread development. Multiple Description Coding(MDC) video applications, as a popular application in the current network, should be reasonably supported in this novel network virtualization environment. In this paper, we address this issue to assign MDC video application into virtual networks with an efficient centralized algorithm(CAMDV). Since this problem is an NP-hard problem, we design an algorithm that can effectively balance the user satisfaction and network resource cost. Previous work just builds a global multicast tree for each description to connect all the destination nodes by breadth-first search strategy or shortest path tree algorithm. But those methods could not achieve an optimal balance or a high-level user satisfaction. By introducing the hierarchical clustering scheme, our algorithm decomposes the whole mapping procedure into multicast tree construction and multipath description distribution. A serial of simulation experiments show that our centralized algorithm could achieve a better performance in balancing the user satisfaction and average mapping cost in comparison with its rivals.

关键词： multiple description coding video multipath programming hierarchical clustering scheme multicast tree construction network virtualization

Achieving Consistence for Cross-Domain WAN Control in Software-Defined Networks

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China Communications 2015年第10期12卷 136-146页

作者： zhou boyang WU Chunming GAO Wen HONG Xiaoyan JIANG Ming CHEN Shuangxi College of Computer Science Zhejiang University Department of Computer Science University of Alabama Institute of Software and Intelligent Technology Hangzhou Dianzi University Division of Information Technology Jiaxing Vocational Technical College

When applying Software-Defined Networks(SDN) to WANs,the SDN flexibility enables the cross-domain control to achieve a better control ***,the control consistence is required by all the cross-domain services,to ensure the data plane configured in consensus for different *** consistence process is complicated by potential failure and errors of *** this paper,we propose a consistence layer to actively and passively snapshot the cross-domain control states,to reduce the complexities of service *** implement the layer and evaluate performance in the PlanetLab testbed for the WAN *** testbed conditions are extremely enlarged comparing to the real *** results show its scalability,reliability and responsiveness in dealing with the control *** the normalized results,the active and passive snapshots are executed with the mean times of 1.873 s and 105 ms in135 controllers,indicating its readiness to be used in the real network.

关键词： software-defined networking distributed control plane cross-domain control

Far-zone contributions of airborne gravity anomalies' upward/downward continuation

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Geodesy and Geodynamics 2016年第6期7卷 444-450页

作者： boyang zhou Zhicai Luo Yihao Wu Yuqiao Cen Department of Surveying and Mapping Guangdong University of Technology School of Geodesy and Geomatics Wuhan University Center for Urban Science and Progress New York University

Airborne gravimetry has become a vital technique in local gravity field approximation, and upward/downward continuation of gravity data is a key process of airborne gravimetry. In these procedures, the integral domain is divided into two parts, namely the near-zone and the far-zone. The far-zone contributions are approximated by the truncation coefficients and a global geo-potential model, and their values are controlled by several issues. This paper investigates the effects of flight height, the size of near-zone cap, and Remove- Compute-Restore （RCR） technique upon far-zone contributions. Results show that at mountainous area the far-zone contributions can be ignored when EIGEN-6C of 360 degree is removed from the gravity data, together with a near-zone cap of 1°and a flight height less than 10 km, while at flat area EIGEN-6C of 180 degree is feasible.

关键词： Airborne gravimetryPoisson integralUpward/downward continuationFat-zone contdbutionsRemove -Compute -Restoretechnique

Low-degree toroidal modes from the Sumatra-Andaman event observed by superconducting gravimeters

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Geodesy and Geodynamics 2019年第6期10卷 477-484页

作者： Chuang Xu Hangtao Yu Guangyu Jian Shiqi Deng boyang zhou Yihao Wu Department of Surveying Engineering School of Civil and Transportation EngineeringGuangdong University of TechnologyNo.100 Waihuan Xi RoadGuangzhou 510006China State Key Laboratory of Geodesy and Earth’s Dynamics Institute of Geodesy and GeophysicsChinese Academy of SciencesNo.340 Xu Dong AvenueWuhan 430077China State Key Laboratory of Information Engineering in Surveying Mapping and Remote SensingWuhan UniversityWuhan 430079China School of Earth Science and Engineering Hohai UniversityNanjing 210098China

The complex frequencies of the low-degree toroidal modes are helpful in constraining the mantle *** the early years,the traditional method to detect the low-degree toroidal modes is seismic approach,which is primarily limited by the horizontal noise of ***,it has been proved that gravity method is ***,we re-estimated or newly estimated the complex frequencies of the toroidal modes below 1.5 mHz excited by the 2004 Sumatra-Andaman event using gravity method in this *** results show that(1)The quality factors of0 T5-0 T9 and1 T2-1 T3 are estimated from superconducting gravity data for the first time;(2)The estimated frequencies and quality factors for0 T2-0 T9 and1 T2-1 T3 are consistent with those provided by previous publications,which verifies the correctness and effectiveness of our estimations;(3)The maximum difference of frequencies between our results and those from CPREM is on the order of 0.01 mHz and the maximum difference of quality factors is at the level of 10.

关键词： Low-degree toroidal modes Superconducting gravity data Complex frequency Quality factor

加氢裂化装置热低压空冷器腐蚀原因分析与对策

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化工技术与开发 2025年第1期54卷 76-78页

作者：高飞毛威王东锋雷锡峰吴琼董标周博洋龙庆兴中国石油广西石化公司广西钦州535008

某炼厂220万t·a^(-1)加氢裂化装置的热低压空冷器管束出现了减薄泄漏的情况,为此对现场的泄漏部位进行了外观检查和内窥镜检测,并对垢样进行了化验分析,认为导致管束泄漏的原因是铵盐腐蚀。采用流程模拟计算了氯化铵的结晶温度,并结合... 详细信息

某炼厂220万t·a^(-1)加氢裂化装置的热低压空冷器管束出现了减薄泄漏的情况,为此对现场的泄漏部位进行了外观检查和内窥镜检测,并对垢样进行了化验分析,认为导致管束泄漏的原因是铵盐腐蚀。采用流程模拟计算了氯化铵的结晶温度,并结合注水情况,确定管束存在垢下腐蚀的风险。提出了增加注水量、改变注水频次、降低介质偏流、加强红外监测等解决措施,以降低空冷发生腐蚀泄漏的风险。

关键词：加氢裂化热低压空冷器泄漏腐蚀原因分析