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Discontinuity development patterns and the challenges for 3D discrete fracture network modeling on complicated exposed rock surfaces 被引量:1
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作者 Wen Zhang Ming Wei +8 位作者 Ying Zhang Tengyue Li Qing Wang Chen Cao Chun Zhu Zhengwei Li Zhenbang Nie Shuonan Wang Han Yin 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第6期2154-2171,共18页
Natural slopes usually display complicated exposed rock surfaces that are characterized by complex and substantial terrain undulation and ubiquitous undesirable phenomena such as vegetation cover and rockfalls.This st... Natural slopes usually display complicated exposed rock surfaces that are characterized by complex and substantial terrain undulation and ubiquitous undesirable phenomena such as vegetation cover and rockfalls.This study presents a systematic outcrop research of fracture pattern variations in a complicated rock slope,and the qualitative and quantitative study of the complex phenomena impact on threedimensional(3D)discrete fracture network(DFN)modeling.As the studies of the outcrop fracture pattern have been so far focused on local variations,thus,we put forward a statistical analysis of global variations.The entire outcrop is partitioned into several subzones,and the subzone-scale variability of fracture geometric properties is analyzed(including the orientation,the density,and the trace length).The results reveal significant variations in fracture characteristics(such as the concentrative degree,the average orientation,the density,and the trace length)among different subzones.Moreover,the density of fracture sets,which is approximately parallel to the slope surface,exhibits a notably higher value compared to other fracture sets across all subzones.To improve the accuracy of the DFN modeling,the effects of three common phenomena resulting from vegetation and rockfalls are qualitatively analyzed and the corresponding quantitative data processing solutions are proposed.Subsequently,the 3D fracture geometric parameters are determined for different areas of the high-steep rock slope in terms of the subzone dimensions.The results show significant variations in the same set of 3D fracture parameters across different regions with density differing by up to tenfold and mean trace length exhibiting differences of 3e4 times.The study results present precise geological structural information,improve modeling accuracy,and provide practical solutions for addressing complex outcrop issues. 展开更多
关键词 Complicated exposed rock surfaces Discontinuity characteristic variation three-dimensional discrete fracture network modeling Outcrop study Vegetation cover and rockfalls
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Intrusion Detection Model Using Chaotic MAP for Network Coding Enabled Mobile Small Cells
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作者 Chanumolu Kiran Kumar Nandhakumar Ramachandran 《Computers, Materials & Continua》 SCIE EI 2024年第3期3151-3176,共26页
Wireless Network security management is difficult because of the ever-increasing number of wireless network malfunctions,vulnerabilities,and assaults.Complex security systems,such as Intrusion Detection Systems(IDS),a... Wireless Network security management is difficult because of the ever-increasing number of wireless network malfunctions,vulnerabilities,and assaults.Complex security systems,such as Intrusion Detection Systems(IDS),are essential due to the limitations of simpler security measures,such as cryptography and firewalls.Due to their compact nature and low energy reserves,wireless networks present a significant challenge for security procedures.The features of small cells can cause threats to the network.Network Coding(NC)enabled small cells are vulnerable to various types of attacks.Avoiding attacks and performing secure“peer”to“peer”data transmission is a challenging task in small cells.Due to the low power and memory requirements of the proposed model,it is well suited to use with constrained small cells.An attacker cannot change the contents of data and generate a new Hashed Homomorphic Message Authentication Code(HHMAC)hash between transmissions since the HMAC function is generated using the shared secret.In this research,a chaotic sequence mapping based low overhead 1D Improved Logistic Map is used to secure“peer”to“peer”data transmission model using lightweight H-MAC(1D-LM-P2P-LHHMAC)is proposed with accurate intrusion detection.The proposed model is evaluated with the traditional models by considering various evaluation metrics like Vector Set Generation Accuracy Levels,Key Pair Generation Time Levels,Chaotic Map Accuracy Levels,Intrusion Detection Accuracy Levels,and the results represent that the proposed model performance in chaotic map accuracy level is 98%and intrusion detection is 98.2%.The proposed model is compared with the traditional models and the results represent that the proposed model secure data transmission levels are high. 展开更多
关键词 network coding small cells data transmission intrusion detection model hashed message authentication code chaotic sequence mapping secure transmission
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Cyber Resilience through Real-Time Threat Analysis in Information Security
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作者 Aparna Gadhi Ragha Madhavi Gondu +1 位作者 Hitendra Chaudhary Olatunde Abiona 《International Journal of Communications, Network and System Sciences》 2024年第4期51-67,共17页
This paper examines how cybersecurity is developing and how it relates to more conventional information security. Although information security and cyber security are sometimes used synonymously, this study contends t... This paper examines how cybersecurity is developing and how it relates to more conventional information security. Although information security and cyber security are sometimes used synonymously, this study contends that they are not the same. The concept of cyber security is explored, which goes beyond protecting information resources to include a wider variety of assets, including people [1]. Protecting information assets is the main goal of traditional information security, with consideration to the human element and how people fit into the security process. On the other hand, cyber security adds a new level of complexity, as people might unintentionally contribute to or become targets of cyberattacks. This aspect presents moral questions since it is becoming more widely accepted that society has a duty to protect weaker members of society, including children [1]. The study emphasizes how important cyber security is on a larger scale, with many countries creating plans and laws to counteract cyberattacks. Nevertheless, a lot of these sources frequently neglect to define the differences or the relationship between information security and cyber security [1]. The paper focus on differentiating between cybersecurity and information security on a larger scale. The study also highlights other areas of cybersecurity which includes defending people, social norms, and vital infrastructure from threats that arise from online in addition to information and technology protection. It contends that ethical issues and the human factor are becoming more and more important in protecting assets in the digital age, and that cyber security is a paradigm shift in this regard [1]. 展开更多
关键词 Cybersecurity Information security network security Cyber Resilience Real-Time Threat Analysis Cyber Threats Cyberattacks Threat Intelligence Machine Learning Artificial Intelligence Threat Detection Threat Mitigation Risk Assessment Vulnerability Management Incident Response security Orchestration Automation Threat Landscape Cyber-Physical Systems Critical Infrastructure Data Protection Privacy Compliance Regulations Policy Ethics CYBERCRIME Threat Actors Threat modeling security Architecture
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Enhanced Security with Improved Defensive Routing Mechanism in Wireless Sensor Networks
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作者 R.Sabitha C.Gokul Prasad S.Karthik 《Computer Systems Science & Engineering》 SCIE EI 2023年第6期2795-2810,共16页
In recent scenario of Wireless Sensor Networks(WSNs),there are many application developed for handling sensitive and private data such as military information,surveillance data,tracking,etc.Hence,the sensor nodes of W... In recent scenario of Wireless Sensor Networks(WSNs),there are many application developed for handling sensitive and private data such as military information,surveillance data,tracking,etc.Hence,the sensor nodes of WSNs are distributed in an intimidating region,which is non-rigid to attacks.The recent research domains of WSN deal with models to handle the WSN communications against malicious attacks and threats.In traditional models,the solution has been made for defending the networks,only to specific attacks.However,in real-time applications,the kind of attack that is launched by the adversary is not known.Additionally,on developing a security mechanism for WSN,the resource constraints of sensor nodes are also to be considered.With that note,this paper presents an Enhanced Security Model with Improved Defensive Routing Mechanism(IDRM)for defending the sensor network from various attacks.Moreover,for efficient model design,the work includes the part of feature evaluation of some general attacks of WSNs.The IDRM also includes determination of optimal secure paths and Node security for secure routing operations.The performance of the proposed model is evaluated with respect to several factors;it is found that the model has achieved better security levels and is efficient than other existing models in WSN communications.It is proven that the proposed IDRM produces 74%of PDR in average and a minimized packet drop of 38%when comparing with the existing works. 展开更多
关键词 Enhanced security model wireless sensor networks improved defensive routing mechanism secure paths node security
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ILSM:Incorporated Lightweight Security Model for Improving QOS in WSN
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作者 Ansar Munir Shah Mohammed Aljubayri +4 位作者 Muhammad Faheem Khan Jarallah Alqahtani Mahmood ul Hassan Adel Sulaiman Asadullah Shaikh 《Computer Systems Science & Engineering》 SCIE EI 2023年第8期2471-2488,共18页
In the network field,Wireless Sensor Networks(WSN)contain prolonged attention due to afresh augmentations.Industries like health care,traffic,defense,and many more systems espoused the WSN.These networks contain tiny ... In the network field,Wireless Sensor Networks(WSN)contain prolonged attention due to afresh augmentations.Industries like health care,traffic,defense,and many more systems espoused the WSN.These networks contain tiny sensor nodes containing embedded processors,TinyOS,memory,and power source.Sensor nodes are responsible for forwarding the data packets.To manage all these components,there is a need to select appropriate parameters which control the quality of service of WSN.Multiple sensor nodes are involved in transmitting vital information,and there is a need for secure and efficient routing to reach the quality of service.But due to the high cost of the network,WSN components have limited resources to manage the network.There is a need to design a lightweight solution that ensures the quality of service in WSN.In this given manner,this study provides the quality of services in a wireless sensor network with a security mechanism.An incorporated hybrid lightweight security model is designed in which random waypoint mobility(RWM)model and grey wolf optimization(GWO)is used to enhance service quality and maintain security with efficient routing.MATLAB version 16 andNetwork Stimulator 2.35(NS2.35)are used in this research to evaluate the results.The overall cost factor is reduced at 60%without the optimization technique and 90.90%reduced by using the optimization technique,which is assessed by calculating the signal-to-noise ratio,overall energy nodes,and communication overhead. 展开更多
关键词 Wireless sensor networks quality of service random waypoint mobility model grey wolf optimization security
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Multilevel security model for ad hoc networks 被引量:1
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作者 Wang Changda Ju Shiguang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第2期391-397,F0003,共8页
Modern battlefield doctrine is based on mobility, flexibility, and rapid response to changing situations. As is well known, mobile ad hoc network systems are among the best utilities for battlefield activity. Although... Modern battlefield doctrine is based on mobility, flexibility, and rapid response to changing situations. As is well known, mobile ad hoc network systems are among the best utilities for battlefield activity. Although much research has been done on secure routing, security issues have largely been ignored in applying mobile ad hoc network theory to computer technology. An ad hoc network is usually assumed to be homogeneous, which is an irrational assumption for armies. It is clear that soldiers, commanders, and commanders-in-chief should have different security levels and computation powers as they have access to asymmetric resources. Imitating basic military rank levels in battlefield situations, how multilevel security can be introduced into ad hoc networks is indicated, thereby controlling restricted classified information flows among nodes that have different security levels. 展开更多
关键词 ad hoc network multilevel security model access control.
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A Three-dimensional IP-based Telecom Metropolitan Area Network Model
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作者 Li Hongbiao (Data Division of ZTE Corporation, Nanjing 210012, China) 《ZTE Communications》 2005年第3期52-55,共4页
The Metropolitan Area Network (MAN) has faced serious problems after years of rapid development. The model of three-dimensional IP-based MAN, proposed by ZTE, is a next-generation MAN solution, which not only solves t... The Metropolitan Area Network (MAN) has faced serious problems after years of rapid development. The model of three-dimensional IP-based MAN, proposed by ZTE, is a next-generation MAN solution, which not only solves the existing problems but also brings new ideas for the development of next-generation MAN. 展开更多
关键词 IP A three-dimensional IP-based Telecom Metropolitan Area network model ZTE MPLS
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Using the Latin Square Design Model in the Prioritzation of Network Security Threats: A Quantitative Study
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作者 Rodney Alexander 《Journal of Information Security》 2020年第2期92-102,共11页
Society is becoming increasingly dependent on cyberspace for both business and pleasure. Cyber attackers continue to attack organizational computer networks, as those same computer networks become increasing critical ... Society is becoming increasingly dependent on cyberspace for both business and pleasure. Cyber attackers continue to attack organizational computer networks, as those same computer networks become increasing critical to organizational business process. Strategic planning and managing IT security risks play an important role in the business and government planning process. Deploying defense in depth security measures can ensure that organizations continue to function in times of crisis. This quantitative study explores whether the Latin Square Design (LSD) model can be effectively applied to the prioritization of cybersecurity threats and to the linking of information assurance defense in-depth measures to those threats. The methods used in this study consisted of scanning 10 Cybersecurity Websites such as the Department of Homeland Security US CERT (United States-Computer Emergency Readiness Team [1]) and the SANS Institute (SysAdmin, Audit, Network and Security [2]) using the Likert Scale Model for the Website’s top ten list of cyber threats facing organizations and the network defense in depth measures to fight those threats. A comparison of each cybersecurity threats was then made using LSD to determine whether the Likert scale and the LSD model could be effectively applied to prioritize information assurance measures to protect organizational computing devices. The findings of the research reject the H0 null hypothesis that LSD does not affect the relationship between the ranking of 10 Cybersecurity websites top ten cybersecurity threats dependent variables and the independent variables of defense in depth measures used in protecting organizational devices against cyber-attacks. 展开更多
关键词 INFORMATION ASSURANCE LATIN SQUARE Design model DEFENSE in Depth INFORMATION Technology network security CYBERsecurity
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Prediction of Salinity Variations in a Tidal Estuary Using Artificial Neural Network and Three-Dimensional Hydrodynamic Models
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作者 Weibo Chen Wencheng Liu +1 位作者 Weiche Huang Hongming Liu 《Computational Water, Energy, and Environmental Engineering》 2017年第1期107-128,共22页
The simulation of salinity at different locations of a tidal river using physically-based hydrodynamic models is quite cumbersome because it requires many types of data, such as hydrological and hydraulic time series ... The simulation of salinity at different locations of a tidal river using physically-based hydrodynamic models is quite cumbersome because it requires many types of data, such as hydrological and hydraulic time series at boundaries, river geometry, and adjusted coefficients. Therefore, an artificial neural network (ANN) technique using a back-propagation neural network (BPNN) and a radial basis function neural network (RBFNN) is adopted as an effective alternative in salinity simulation studies. The present study focuses on comparing the performance of BPNN, RBFNN, and three-dimensional hydrodynamic models as applied to a tidal estuarine system. The observed salinity data sets collected from 18 to 22 May, 16 to 22 October, and 26 to 30 October 2002 (totaling 4320 data points) were used for BPNN and RBFNN model training and for hydrodynamic model calibration. The data sets collected from 30 May to 2 June and 11 to 15 November 2002 (totaling 2592 data points) were adopted for BPNN and RBFNN model verification and for hydrodynamic model verification. The results revealed that the ANN (BPNN and RBFNN) models were capable of predicting the nonlinear time series behavior of salinity to the multiple forcing signals of water stages at different stations and freshwater input at upstream boundaries. The salinity predicted by the ANN models was better than that predicted by the physically based hydrodynamic model. This study suggests that BPNN and RBFNN models are easy-to-use modeling tools for simulating the salinity variation in a tidal estuarine system. 展开更多
关键词 SALINITY Variation Artificial NEURAL network Backpropagation Algorithm Radial Basis Function NEURAL network three-dimensional Hydrodynamic model TIDAL ESTUARY
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Researches On The Network Security Evaluation Method Based Bn BP Neural Network
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作者 Zhang Yibin Yan Zequan 《International Journal of Technology Management》 2014年第9期93-95,共3页
关键词 BP神经网络算法 安全评估方法 安全评价指标体系 计算机网络 BN 基础 专题 安全评价方法
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Anomaly-based model for detecting HTTP-tunnel traffic using network behavior analysis 被引量:2
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作者 李世淙 Yun Xiaochun Zhang Yongzheng 《High Technology Letters》 EI CAS 2014年第1期63-69,共7页
Increasing time-spent online has amplified users' exposure to the threat of information leakage.Although existing security systems(such as firewalls and intrusion detection systems) can satisfy most of the securit... Increasing time-spent online has amplified users' exposure to the threat of information leakage.Although existing security systems(such as firewalls and intrusion detection systems) can satisfy most of the security requirements of network administrators,they are not suitable for detecting the activities of applying the HTTP-tunnel technique to steal users' private information.This paper focuses on a network behavior-based method to address the limitations of the existing protection systems.At first,it analyzes the normal network behavior pattern over HTTP traffic and select four features.Then,it presents an anomaly-based detection model that applies a hierarchical clustering technique and a scoring mechanism.It also uses real-world data to validate that the selected features are useful.The experiments have demonstrated that the model could achieve over 93%hit-rate with only about 3%falsepositive rate.It is regarded confidently that the approach is a complementary technique to the existing security systems. 展开更多
关键词 网络行为分析 HTTP隧道 入侵检测系统 检测模型 交通网络 异常 安全系统 隧道技术
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A Secure and Energy-Balanced Routing Scheme for Mobile Wireless Sensor Network
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作者 Bei Liu Yuanming Wu 《Wireless Sensor Network》 2015年第11期137-148,共12页
Mobile wireless sensor network (MWSN) has the features of self-organization, multiple-hop and limited energy resources. It is vulnerable to a wide set of security attacks, including those targeting the routing protoco... Mobile wireless sensor network (MWSN) has the features of self-organization, multiple-hop and limited energy resources. It is vulnerable to a wide set of security attacks, including those targeting the routing protocol functionality. In this paper, the existing security problems and solutions in MWSN are summarized, and then a trust management system based on neighbor monitoring is proposed. In the trust management system, the trust value is calculated by the neighbor monitoring mechanism, and the direct trust value and the indirect trust value are combined to establish the distributed trust model to detect the malicious nodes. The consistency check algorithm is capable of defending against the attacks on the trust model. In addition, because of the limited energy of the sensor nodes, the energy-balanced algorithm is introduced to prolong the lifespan of MWSN. The residual energy and energy density are considered in the routing decision. Finally, the simulation experiments show that the proposed algorithm can detect the malicious nodes effectively and achieve the energy-balanced goal to prolong the lifespan of MWSN. 展开更多
关键词 MOBILE WIRELESS Sensor network network security TRUST model Energy-Balanced
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Classification and Review of Security Schemes in Mobile Computing
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作者 Sathish Alampalayam Kumar 《Wireless Sensor Network》 2010年第6期419-440,共22页
In this paper, we present the classification and review of security schemes in mobile computing system. We classify these schemes based on types the infrastructure used in the mobile computing system-Mobile Ad Hoc Net... In this paper, we present the classification and review of security schemes in mobile computing system. We classify these schemes based on types the infrastructure used in the mobile computing system-Mobile Ad Hoc Networks (MANET) and Mobile Agent model. Mobile Ad Hoc Networks are pervasive, ubiquitous and without any centralized authority. These unique characteristics, combined with ever-increasing security threats, demand solutions in securing ad hoc networks prior to their deployment in commercial and military applications. This paper reviews the prevailing mobile ad hoc network security threats, the existing solution schemes, their limitations and open research issues. We also explain the Intrusion detection and response technique as an alternate method to protect the MANET based mobile computing systems and their approaches. A literature review of important existing Intrusion Detection approaches and Intrusion Response Approaches for MANET is also presented. This paper also presents the limitations of existing Intrusion Detection and Response Approaches for MANET and open research issues in providing MANET security. With respect to Mobile Agent based mobile computing system, we have presented the classification of various types of security attacks in Mobile Agent based model and presented the security solutions for those type of attacks proposed by the various schemes and the open research issues in providing security for Mobile Agent based mobile computing system. Such classification enhances the understanding of the proposed security schemes in the mobile computing system, assists in the development and enhancement of schemes in the future and helps in choosing an appropriate scheme while implementing a mobile computing system. 展开更多
关键词 WIRELESS Sensor networks BETA TRUST model TRUST ROUTING PROTOCOL network security TRUST Evaluation
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Research on Beta Trust Model of Wireless Sensor Networks Based on Energy Load Balancing
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作者 Danwei Chen Xizhou Yu Xianghui Dong 《Wireless Sensor Network》 2010年第5期373-380,共8页
This paper proposed beta trust model based on energy load balancing combines the recent achievements of the trust models in distributed networks, together with the characteristics of wireless sensor networks. The inte... This paper proposed beta trust model based on energy load balancing combines the recent achievements of the trust models in distributed networks, together with the characteristics of wireless sensor networks. The inter-node trust relation is established after an overall evaluation of node trust value based on the monitor results of the node packets forwarding behavior conducted by inter-node collaboration. Due to the node energy limitation in wireless sensor networks, energy load balancing mechanism is applied to prolong the node survival time. And the redundant routing protocol involves the presented trust model to develop the novel trust routing protocol of beta trust model based on energy load balancing. Simulation performance demonstrates that the beta trust model based on energy load balancing outperforms current schemes in energy consumption. 展开更多
关键词 WIRELESS Sensor networks BETA TRUST model TRUST ROUTING PROTOCOL network security TRUST Evaluation
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Vulnerability Detection of Ethereum Smart Contract Based on SolBERT-BiGRU-Attention Hybrid Neural Model
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作者 Guangxia Xu Lei Liu Jingnan Dong 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第10期903-922,共20页
In recent years,with the great success of pre-trained language models,the pre-trained BERT model has been gradually applied to the field of source code understanding.However,the time cost of training a language model ... In recent years,with the great success of pre-trained language models,the pre-trained BERT model has been gradually applied to the field of source code understanding.However,the time cost of training a language model from zero is very high,and how to transfer the pre-trained language model to the field of smart contract vulnerability detection is a hot research direction at present.In this paper,we propose a hybrid model to detect common vulnerabilities in smart contracts based on a lightweight pre-trained languagemodel BERT and connected to a bidirectional gate recurrent unitmodel.The downstream neural network adopts the bidirectional gate recurrent unit neural network model with a hierarchical attention mechanism to mine more semantic features contained in the source code of smart contracts by using their characteristics.Our experiments show that our proposed hybrid neural network model SolBERT-BiGRU-Attention is fitted by a large number of data samples with smart contract vulnerabilities,and it is found that compared with the existing methods,the accuracy of our model can reach 93.85%,and the Micro-F1 Score is 94.02%. 展开更多
关键词 Smart contract pre-trained language model deep learning recurrent neural network blockchain security
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Application Research on Two-Layer Threat Prediction Model Based on Event Graph
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作者 Shuqin Zhang Xinyu Su +2 位作者 Yunfei Han Tianhui Du Peiyu Shi 《Computers, Materials & Continua》 SCIE EI 2023年第12期3993-4023,共31页
Advanced Persistent Threat(APT)is now the most common network assault.However,the existing threat analysis models cannot simultaneously predict the macro-development trend and micro-propagation path of APT attacks.The... Advanced Persistent Threat(APT)is now the most common network assault.However,the existing threat analysis models cannot simultaneously predict the macro-development trend and micro-propagation path of APT attacks.They cannot provide rapid and accurate early warning and decision responses to the present system state because they are inadequate at deducing the risk evolution rules of network threats.To address the above problems,firstly,this paper constructs the multi-source threat element analysis ontology(MTEAO)by integrating multi-source network security knowledge bases.Subsequently,based on MTEAO,we propose a two-layer threat prediction model(TL-TPM)that combines the knowledge graph and the event graph.The macro-layer of TL-TPM is based on the knowledge graph to derive the propagation path of threats among devices and to correlate threat elements for threat warning and decision-making;The micro-layer ingeniously maps the attack graph onto the event graph and derives the evolution path of attack techniques based on the event graph to improve the explainability of the evolution of threat events.The experiment’s results demonstrate that TL-TPM can completely depict the threat development trend,and the early warning results are more precise and scientific,offering knowledge and guidance for active defense. 展开更多
关键词 Knowledge graph multi-source data fusion network security threat modeling event graph absorbing Markov chain threat propagation path
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Local Trade Networks among Farmers and Traders
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作者 Abdul-Samad Abdul-Rahaman Patience Pokuaa Gambrah 《Social Networking》 2023年第4期93-110,共18页
Both farmers and traders benefit from trade networking, which is crucial for the local economy. Therefore, it is crucial to understand how these networks operate, and how they can be managed more effectively. Througho... Both farmers and traders benefit from trade networking, which is crucial for the local economy. Therefore, it is crucial to understand how these networks operate, and how they can be managed more effectively. Throughout this study, we examine the economic networks formed between farmers and traders through the trade of food products. These networks are analyzed from the perspective of their structure and the factors that influence their development. Using data from 18 farmers and 15 traders, we applied exponential random graph models. The results of our study showed that connectivity, Popularity Spread, activity spread, good transportation systems, and high yields all affected the development of networks. Therefore, farmers’ productivity and high market demand can contribute to local food-crop trade. The network was not affected by reciprocity, open markets, proximity to locations, or trade experience of actors. Policy makers should consider these five factors when formulating policies for local food-crop trade. Additionally, local actors should be encouraged to use these factors to improve their network development. However, it is important to note that these factors alone cannot guarantee success. Policy makers and actors must also consider other factors such as legal frameworks, economic policies, and resource availability. Our approach can be used in future research to determine how traders and farmers can enhance productivity and profit in West Africa. This study addresses a research gap by examining factors influencing local food trade in a developing country. 展开更多
关键词 Local Trade Social network Analysis Food Trade Exponential Random Graph models (ERGM) Food security
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中国碳酸锂经济安全预警研究
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作者 郑明贵 刘丽珍 +1 位作者 陶思敏 彭群婷 《盐湖研究》 CAS CSCD 2024年第2期117-126,共10页
为深入研究碳酸锂经济安全,文章从资源禀赋、进口依赖、获取成本和地缘政治四个维度出发,构建了中国碳酸锂经济安全评价指标体系,运用常权和变权模型评估了2009—2020年中国碳酸锂经济安全状况,采用GM(1,1)模型及BP神经网络模型对2021—... 为深入研究碳酸锂经济安全,文章从资源禀赋、进口依赖、获取成本和地缘政治四个维度出发,构建了中国碳酸锂经济安全评价指标体系,运用常权和变权模型评估了2009—2020年中国碳酸锂经济安全状况,采用GM(1,1)模型及BP神经网络模型对2021—2035年中国碳酸锂经济安全进行预警研究。结果表明:1.进口集中度、对外依存度及运输风险是影响碳酸锂经济安全的主要因素;2.2009—2020年中国碳酸锂经济安全总体呈下降趋势,安全等级由黄色—基本安全等级波动下降至橙色—不安全等级,资源禀赋和进口依赖是导致碳酸锂安全等级较低的主要原因;3.2021—2035年中国碳酸锂经济安全评分不断下降,除2021年和2026年处于黄色—基本安全等级外,其余年份均处于橙色—不安全等级。 展开更多
关键词 碳酸锂 经济安全 预警 GM(1 1)模型 BP神经网络
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基于VOSviewer的测评机构市场竞争特征分析模型的构建
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作者 王云丽 杨文焕 +2 位作者 邵云霞 成彬 陈志宾 《现代信息科技》 2024年第7期151-160,共10页
网络安全等级保护在网络安全保障、网络强国建设方面发挥着至关重要的作用。随着资质管理从审核推荐模式向服务认证模式的转变,网络安全等级保护测评机构的资质管理得到网络安全界越来越多的关注。在分析网络安全等级保护测评机构投标... 网络安全等级保护在网络安全保障、网络强国建设方面发挥着至关重要的作用。随着资质管理从审核推荐模式向服务认证模式的转变,网络安全等级保护测评机构的资质管理得到网络安全界越来越多的关注。在分析网络安全等级保护测评机构投标项目信息的基础上,应用VOSviewer知识图谱软件构建一种市场竞争特征分析模型,为等级测评行业的高质量发展提供参考借鉴。首先对采集数据进行清洗以及基于相似度去重;然后采用机器学习算法对项目信息进行“关键词”(项目类型、项目所属行业)的抽取和标注;最后将项目信息进行RefWorks格式转换并导入VOSviewer,可视化呈现测评机构的竞争关系和市场特征。 展开更多
关键词 网络安全等级保护测评机构 VOSviewer 项目信息 市场竞争特征 模型构建
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基于KAP理论的大学生网络安全教育研究
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作者 李媛媛 袁玉林 随力瑞 《中国安全科学学报》 CAS CSCD 北大核心 2024年第5期1-8,共8页
为改善大学生网络安全教育现状,提高大学生网络安全教育水平,结合知识-态度-行为(KAP)理论,构建大学生安全教育KAP模型;通过问卷发放和筛选,获取659份有效问卷;采用结构方程模型(SEM)检验网络安全教育对网络安全认知、网络安全态度、网... 为改善大学生网络安全教育现状,提高大学生网络安全教育水平,结合知识-态度-行为(KAP)理论,构建大学生安全教育KAP模型;通过问卷发放和筛选,获取659份有效问卷;采用结构方程模型(SEM)检验网络安全教育对网络安全认知、网络安全态度、网络安全行为的影响,以及可能存在的中介作用影响路径。结果表明:网络安全教育显著影响网络安全认知、网络安全态度、网络安全行为,其中,网络安全认知、网络安全态度起到独立中介及链式中介作用;法律道德教育、知识教育、实践活动、榜样引领均能直接影响网络安全行为,其中,法律道德教育对网络安全行为的影响最强,知识教育次之,实践活动和榜样引领最弱。在具体作用路径方面,法律道德教育主要通过直接效应来影响网络安全行为,知识教育、实践活动、榜样引领主要通过安全认知间接影响网络安全行为。 展开更多
关键词 知识-态度-行为(KAP) 网络安全教育 法律道德教育 实践活动 榜样引领 结构方程模型(SEM)
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