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Anti-interference self-alignment algorithm by attitude optimization estimation for SINS on a rocking base
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作者 XUE Haijian WANG Tao +2 位作者 CAI Xinghui WANG Jintao LIU Fei 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第5期1333-1342,共10页
The performance of a strapdown inertial navigation system(SINS)largely depends on the accuracy and rapidness of the initial alignment.A novel anti-interference self-alignment algorithm by attitude optimization estimat... The performance of a strapdown inertial navigation system(SINS)largely depends on the accuracy and rapidness of the initial alignment.A novel anti-interference self-alignment algorithm by attitude optimization estimation for SINS on a rocking base is presented in this paper.The algorithm transforms the initial alignment into the initial attitude determination problem by using infinite vector observations to remove the angular motions,the SINS alignment is heuristically established as an optimiza-tion problem of finding the minimum eigenvector.In order to further improve the alignment precision,an adaptive recursive weighted least squares(ARWLS)curve fitting algorithm is used to fit the translational motion interference-contaminated reference vectors according to their time domain characteristics.Simulation studies and experimental results favorably demonstrate its rapidness,accuracy and robustness. 展开更多
关键词 strapdown inertial navigation system(SINS) initial alignment anti-interfereNCE rocking base adaptive recursive weighted least squares(ARWLS)
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LCD面板C/FOG工艺制造虚拟计量方法研究
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作者 刘暾东 黄智斌 +2 位作者 高凤强 郑鹏 谢玉练 《仪器仪表学报》 EI CAS CSCD 北大核心 2024年第1期16-25,共10页
针对液晶显示器(LCD)面板的“Chip/FPC on Glass”(C/FOG)工艺生产制造过程中存在的计量延迟大、生产异常无法提前预测的问题,本文提出一种基于神经网络的C/FOG工艺生产制造虚拟计量方法。该方法利用生产机台上的传感器采集生产过程中... 针对液晶显示器(LCD)面板的“Chip/FPC on Glass”(C/FOG)工艺生产制造过程中存在的计量延迟大、生产异常无法提前预测的问题,本文提出一种基于神经网络的C/FOG工艺生产制造虚拟计量方法。该方法利用生产机台上的传感器采集生产过程中的过程状态数据,构建基于多尺度一维卷积及通道注意力模型(MS1DC-CA)的虚拟计量模型。通过多个尺度的卷积核提取不同尺度范围内的状态数据特征。在对含有缺失值的原始数据预处理中,提出了基于粒子群算法改进的K近邻填补方法(PSO-KNN Imputation)进行缺失值填充,保留特征的同时,减少因填充值引入的干扰。最后在实际生产采集的数据上进行实验对比分析,实际不良率主要集中在0.1%~0.5%,该虚拟计量模型的拟合均方误差为0.397 7‱,低于其他现有拟合模型,在平均绝对误差、对称平均绝对百分比误差和拟合优度3种评价指标下也均优于其他现有的拟合模型,具有良好的预测性能。 展开更多
关键词 C/fog工艺 虚拟计量 缺失值填充 多尺度一维卷积 通道注意力
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Joint Optimization of Energy Consumption and Network Latency in Blockchain-Enabled Fog Computing Networks
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作者 Huang Xiaoge Yin Hongbo +3 位作者 Cao Bin Wang Yongsheng Chen Qianbin Zhang Jie 《China Communications》 SCIE CSCD 2024年第4期104-119,共16页
Fog computing is considered as a solution to accommodate the emergence of booming requirements from a large variety of resource-limited Internet of Things(IoT)devices.To ensure the security of private data,in this pap... Fog computing is considered as a solution to accommodate the emergence of booming requirements from a large variety of resource-limited Internet of Things(IoT)devices.To ensure the security of private data,in this paper,we introduce a blockchain-enabled three-layer device-fog-cloud heterogeneous network.A reputation model is proposed to update the credibility of the fog nodes(FN),which is used to select blockchain nodes(BN)from FNs to participate in the consensus process.According to the Rivest-Shamir-Adleman(RSA)encryption algorithm applied to the blockchain system,FNs could verify the identity of the node through its public key to avoid malicious attacks.Additionally,to reduce the computation complexity of the consensus algorithms and the network overhead,we propose a dynamic offloading and resource allocation(DORA)algorithm and a reputation-based democratic byzantine fault tolerant(R-DBFT)algorithm to optimize the offloading decisions and decrease the number of BNs in the consensus algorithm while ensuring the network security.Simulation results demonstrate that the proposed algorithm could efficiently reduce the network overhead,and obtain a considerable performance improvement compared to the related algorithms in the previous literature. 展开更多
关键词 blockchain energy consumption fog computing network Internet of Things LATENCY
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Target Detection Algorithm in Foggy Scenes Based on Dual Subnets
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作者 Yuecheng Yu Liming Cai +3 位作者 Anqi Ning Jinlong Shi Xudong Chen Shixin Huang 《Computers, Materials & Continua》 SCIE EI 2024年第2期1915-1931,共17页
Under the influence of air humidity,dust,aerosols,etc.,in real scenes,haze presents an uneven state.In this way,the image quality and contrast will decrease.In this case,It is difficult to detect the target in the ima... Under the influence of air humidity,dust,aerosols,etc.,in real scenes,haze presents an uneven state.In this way,the image quality and contrast will decrease.In this case,It is difficult to detect the target in the image by the universal detection network.Thus,a dual subnet based on multi-task collaborative training(DSMCT)is proposed in this paper.Firstly,in the training phase,the Gated Context Aggregation Network(GCANet)is used as the supervisory network of YOLOX to promote the extraction of clean information in foggy scenes.In the test phase,only the YOLOX branch needs to be activated to ensure the detection speed of the model.Secondly,the deformable convolution module is used to improve GCANet to enhance the model’s ability to capture details of non-homogeneous fog.Finally,the Coordinate Attention mechanism is introduced into the Vision Transformer and the backbone network of YOLOX is redesigned.In this way,the feature extraction ability of the network for deep-level information can be enhanced.The experimental results on artificial fog data set FOG_VOC and real fog data set RTTS show that the map value of DSMCT reached 86.56%and 62.39%,respectively,which was 2.27%and 4.41%higher than the current most advanced detection model.The DSMCT network has high practicality and effectiveness for target detection in real foggy scenes. 展开更多
关键词 Target detection fog target detection YOLOX twin network multi-task learning
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Hierarchical Privacy Protection Model in Advanced Metering Infrastructure Based on Cloud and Fog Assistance
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作者 Linghong Kuang Wenlong Shi Jing Zhang 《Computers, Materials & Continua》 SCIE EI 2024年第8期3193-3219,共27页
The Advanced Metering Infrastructure(AMI),as a crucial subsystem in the smart grid,is responsible for measuring user electricity consumption and plays a vital role in communication between providers and consumers.Howe... The Advanced Metering Infrastructure(AMI),as a crucial subsystem in the smart grid,is responsible for measuring user electricity consumption and plays a vital role in communication between providers and consumers.However,with the advancement of information and communication technology,new security and privacy challenges have emerged for AMI.To address these challenges and enhance the security and privacy of user data in the smart grid,a Hierarchical Privacy Protection Model in Advanced Metering Infrastructure based on Cloud and Fog Assistance(HPPM-AMICFA)is proposed in this paper.The proposed model integrates cloud and fog computing with hierarchical threshold encryption,offering a flexible and efficient privacy protection solution that significantly enhances data security in the smart grid.The methodology involves setting user protection levels by processing missing data and utilizing fuzzy comprehensive analysis to evaluate user importance,thereby assigning appropriate protection levels.Furthermore,a hierarchical threshold encryption algorithm is developed to provide differentiated protection strategies for fog nodes based on user IDs,ensuring secure aggregation and encryption of user data.Experimental results demonstrate that HPPM-AMICFA effectively resists various attack strategies while minimizing time costs,thereby safeguarding user data in the smart grid. 展开更多
关键词 AMI cloud and fog assistance fuzzy comprehensive analysis hierarchical threshold encryption
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Enhanced Hybrid Equilibrium Strategy in Fog-Cloud Computing Networks with Optimal Task Scheduling
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作者 Muchang Rao Hang Qin 《Computers, Materials & Continua》 SCIE EI 2024年第5期2647-2672,共26页
More devices in the Intelligent Internet of Things(AIoT)result in an increased number of tasks that require low latency and real-time responsiveness,leading to an increased demand for computational resources.Cloud com... More devices in the Intelligent Internet of Things(AIoT)result in an increased number of tasks that require low latency and real-time responsiveness,leading to an increased demand for computational resources.Cloud computing’s low-latency performance issues in AIoT scenarios have led researchers to explore fog computing as a complementary extension.However,the effective allocation of resources for task execution within fog environments,characterized by limitations and heterogeneity in computational resources,remains a formidable challenge.To tackle this challenge,in this study,we integrate fog computing and cloud computing.We begin by establishing a fog-cloud environment framework,followed by the formulation of a mathematical model for task scheduling.Lastly,we introduce an enhanced hybrid Equilibrium Optimizer(EHEO)tailored for AIoT task scheduling.The overarching objective is to decrease both the makespan and energy consumption of the fog-cloud system while accounting for task deadlines.The proposed EHEO method undergoes a thorough evaluation against multiple benchmark algorithms,encompassing metrics likemakespan,total energy consumption,success rate,and average waiting time.Comprehensive experimental results unequivocally demonstrate the superior performance of EHEO across all assessed metrics.Notably,in the most favorable conditions,EHEO significantly diminishes both the makespan and energy consumption by approximately 50%and 35.5%,respectively,compared to the secondbest performing approach,which affirms its efficacy in advancing the efficiency of AIoT task scheduling within fog-cloud networks. 展开更多
关键词 Artificial intelligence of things fog computing task scheduling equilibrium optimizer differential evaluation algorithm local search
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Hybrid Approach for Cost Efficient Application Placement in Fog-Cloud Computing Environments
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作者 Abdulelah Alwabel Chinmaya Kumar Swain 《Computers, Materials & Continua》 SCIE EI 2024年第6期4127-4148,共22页
Fog computing has recently developed as a new paradigm with the aim of addressing time-sensitive applications better than with cloud computing by placing and processing tasks in close proximity to the data sources.How... Fog computing has recently developed as a new paradigm with the aim of addressing time-sensitive applications better than with cloud computing by placing and processing tasks in close proximity to the data sources.However,the majority of the fog nodes in this environment are geographically scattered with resources that are limited in terms of capabilities compared to cloud nodes,thus making the application placement problem more complex than that in cloud computing.An approach for cost-efficient application placement in fog-cloud computing environments that combines the benefits of both fog and cloud computing to optimize the placement of applications and services while minimizing costs.This approach is particularly relevant in scenarios where latency,resource constraints,and cost considerations are crucial factors for the deployment of applications.In this study,we propose a hybrid approach that combines a genetic algorithm(GA)with the Flamingo Search Algorithm(FSA)to place application modules while minimizing cost.We consider four cost-types for application deployment:Computation,communication,energy consumption,and violations.The proposed hybrid approach is called GA-FSA and is designed to place the application modules considering the deadline of the application and deploy them appropriately to fog or cloud nodes to curtail the overall cost of the system.An extensive simulation is conducted to assess the performance of the proposed approach compared to other state-of-the-art approaches.The results demonstrate that GA-FSA approach is superior to the other approaches with respect to task guarantee ratio(TGR)and total cost. 展开更多
关键词 Placement mechanism application module placement fog computing cloud computing genetic algorithm flamingo search algorithm
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Fitness Sharing Chaotic Particle Swarm Optimization (FSCPSO): A Metaheuristic Approach for Allocating Dynamic Virtual Machine (VM) in Fog Computing Architecture
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作者 Prasanna Kumar Kannughatta Ranganna Siddesh Gaddadevara Matt +2 位作者 Chin-Ling Chen Ananda Babu Jayachandra Yong-Yuan Deng 《Computers, Materials & Continua》 SCIE EI 2024年第8期2557-2578,共22页
In recent decades,fog computing has played a vital role in executing parallel computational tasks,specifically,scientific workflow tasks.In cloud data centers,fog computing takes more time to run workflow applications... In recent decades,fog computing has played a vital role in executing parallel computational tasks,specifically,scientific workflow tasks.In cloud data centers,fog computing takes more time to run workflow applications.Therefore,it is essential to develop effective models for Virtual Machine(VM)allocation and task scheduling in fog computing environments.Effective task scheduling,VM migration,and allocation,altogether optimize the use of computational resources across different fog nodes.This process ensures that the tasks are executed with minimal energy consumption,which reduces the chances of resource bottlenecks.In this manuscript,the proposed framework comprises two phases:(i)effective task scheduling using a fractional selectivity approach and(ii)VM allocation by proposing an algorithm by the name of Fitness Sharing Chaotic Particle Swarm Optimization(FSCPSO).The proposed FSCPSO algorithm integrates the concepts of chaos theory and fitness sharing that effectively balance both global exploration and local exploitation.This balance enables the use of a wide range of solutions that leads to minimal total cost and makespan,in comparison to other traditional optimization algorithms.The FSCPSO algorithm’s performance is analyzed using six evaluation measures namely,Load Balancing Level(LBL),Average Resource Utilization(ARU),total cost,makespan,energy consumption,and response time.In relation to the conventional optimization algorithms,the FSCPSO algorithm achieves a higher LBL of 39.12%,ARU of 58.15%,a minimal total cost of 1175,and a makespan of 85.87 ms,particularly when evaluated for 50 tasks. 展开更多
关键词 fog computing fractional selectivity approach particle swarm optimization algorithm task scheduling virtual machine allocation
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YOLO-FOG雾天目标检测算法
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作者 谷芳 朱凯 《装备机械》 2024年第2期1-4,30,共5页
雾天条件下,图像质量较低,导致目标检测存在难度。传统的YOLOv5s算法可以在雾天环境中进行检测,但是检测速度慢。对此,提出一种名为YOLO-FOG的雾天目标检测算法,可以提高雾天环境中的检测速度。这一算法在主干网络部分使用RepVGG结构,... 雾天条件下,图像质量较低,导致目标检测存在难度。传统的YOLOv5s算法可以在雾天环境中进行检测,但是检测速度慢。对此,提出一种名为YOLO-FOG的雾天目标检测算法,可以提高雾天环境中的检测速度。这一算法在主干网络部分使用RepVGG结构,减小计算量,提高特征表示能力,加快推理速度,以提高检测的实时性。试验结果表明,针对RTTS数据集,自行车、公共汽车、汽车、摩托车、行人五类目标的平均精度依次可以达到81.72%、79.99%、89.24%、73.46%、83.34%,并且识别时间仅为每张0.065 s。YOLO-FOG雾天目标检测算法兼顾准确性和实时性,具有良好的应用前景。 展开更多
关键词 目标 检测 算法
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FOG Bonding 电阻降低方案及机理探究
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作者 韩鑫 王晓杰 +3 位作者 唐乌力吉白尔 谢建云 薛海林 闫亮 《中国科技纵横》 2024年第5期113-115,共3页
近年来,中小尺寸产品客户端上线TP问题频发,其中有一类TP不良由FOG Bonding电阻异常偏大导致,但二次因未知。FOG堆叠结构为PNL+ACF(异方性导电胶)+FPC,但PNL、FPC为走线电阻,本身电阻较小(<1Ω),故不考虑此影响。基于此,重点研究FOG ... 近年来,中小尺寸产品客户端上线TP问题频发,其中有一类TP不良由FOG Bonding电阻异常偏大导致,但二次因未知。FOG堆叠结构为PNL+ACF(异方性导电胶)+FPC,但PNL、FPC为走线电阻,本身电阻较小(<1Ω),故不考虑此影响。基于此,重点研究FOG Bonding接触电阻。首先建立机理模型并进行探究,然后通过调整FOG Bonding参数,使ACF导电粒子的爆破状态和胶体的固化状态达到最优,最终降低电阻。 展开更多
关键词 fog Bonding 接触电阻 ACF爆破 ACF固化
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Production of Artificial Fog in the PAVIN Fog and Rain Platform: In Search of Big Droplets Fog
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作者 Pierre Duthon Mickaël Ferreira Fernandes Sébastien Liandrat 《Atmospheric and Climate Sciences》 2024年第1期42-61,共20页
In fog, visibility is reduced. This reduction in visibility is measured by the meteorological optical range (MOR), which is important for studying human perception and various sensors in foggy conditions. The Cerema P... In fog, visibility is reduced. This reduction in visibility is measured by the meteorological optical range (MOR), which is important for studying human perception and various sensors in foggy conditions. The Cerema PAVIN Fog & Rain platform is capable of producing calibrated fog in order to better analyses it and understand its consequences. The problem is that the droplets produced by the platform are not large enough to resemble real fog. This can have a major impact on measurements since the interaction between electromagnetic waves and fog depends on the wavelength and diameter of the droplets. To remedy this, Cerema is building a new platform with new equipment capable of generating fog. This study analyses different nozzles and associated usage parameters such as the type of water used and the pressure used. The aim is to select the best nozzle with the associated parameters for producing large-diameter droplets and therefore more realistic fog. 展开更多
关键词 fog Physical Simulation Droplets Size Distribution Meteorological Optical Range
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Examining the Experiences and Challenges of Haze-Fog Governance in China
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作者 Renrui Wang 《Journal of Geoscience and Environment Protection》 2024年第4期45-58,共14页
With the rapid development of industrialisation and urbanisation, China is facing the challenge of severe HF (Haze-Fog) pollution. This essay compares the advantages and disadvantages of China’s HF management and sum... With the rapid development of industrialisation and urbanisation, China is facing the challenge of severe HF (Haze-Fog) pollution. This essay compares the advantages and disadvantages of China’s HF management and summarizes the important lessons China can teach the rest of the world about applying this tactic. China’s capabilities in the digital economy, National Innovation Demonstration Zones, and urban innovation systems are examined in this article, along with its shortcomings in information mechanisms and pollution sources. This essay also summarizes China’s achievements, particularly regarding local autonomy. The essay goes on to say, however, that China is probably going to be under more pressure to manage HF in the future, both in terms of long-term solutions and the economy. 展开更多
关键词 Haze-fog Control Digital Economy National Innovation Demonstration Zones Local Autonomy
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Anti-interference ultra-wideband system based on spreading and interleaving 被引量:1
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作者 Zhang Shibing Zhang Lijun 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2007年第2期236-242,共7页
To suppress the interference in the ultra-wideband (AI-UWB) system is a challenging problem. An anti-interference multiband orthogonal frequency-division multiplexing ultra-wideband (AI-UWB) system, based on sprea... To suppress the interference in the ultra-wideband (AI-UWB) system is a challenging problem. An anti-interference multiband orthogonal frequency-division multiplexing ultra-wideband (AI-UWB) system, based on spreading and interleaving is addressed. It will exploit the frequency diversity across the subcarriers and provide the robustness to narrow-band interference, by spreading the coded bit streams within each sub-band and interleaving across all sub-bands. Simulating results show that the spreading and interleaving provide about 5 dB to 10 dB advantages over the conventional multiband orthogonal frequency-division multiplexing ultra-wideband system in signal-to-interference ratio. Spreading and interleaving is an effective cure for enhancing the robustness to narrowband interference. 展开更多
关键词 Communications technology anti-interfereNCE SPREADING INTERLEAVING Ultra-wideband.
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Securing 3D Point and Mesh Fog Data Using Novel Chaotic Cat Map 被引量:1
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作者 K.Priyadarsini Arun Kumar Sivaraman +1 位作者 Abdul Quadir Md Areej Malibari 《Computers, Materials & Continua》 SCIE EI 2023年第3期6703-6717,共15页
With the rapid evolution of Internet technology,fog computing has taken a major role in managing large amounts of data.The major concerns in this domain are security and privacy.Therefore,attaining a reliable level of... With the rapid evolution of Internet technology,fog computing has taken a major role in managing large amounts of data.The major concerns in this domain are security and privacy.Therefore,attaining a reliable level of confidentiality in the fog computing environment is a pivotal task.Among different types of data stored in the fog,the 3D point and mesh fog data are increasingly popular in recent days,due to the growth of 3D modelling and 3D printing technologies.Hence,in this research,we propose a novel scheme for preserving the privacy of 3D point and mesh fog data.Chaotic Cat mapbased data encryption is a recently trending research area due to its unique properties like pseudo-randomness,deterministic nature,sensitivity to initial conditions,ergodicity,etc.To boost encryption efficiency significantly,in this work,we propose a novel Chaotic Cat map.The sequence generated by this map is used to transform the coordinates of the fog data.The improved range of the proposed map is depicted using bifurcation analysis.The quality of the proposed Chaotic Cat map is also analyzed using metrics like Lyapunov exponent and approximate entropy.We also demonstrate the performance of the proposed encryption framework using attacks like brute-force attack and statistical attack.The experimental results clearly depict that the proposed framework produces the best results compared to the previous works in the literature. 展开更多
关键词 Chaotic cat map fog computing ENCRYPTION 3D point fog 3D mesh
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Static-shift suppression and anti-interference signal processing for CSAMT based on Guided Image Filtering
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作者 Enhua Jiang Rujun Chen +2 位作者 Debin Zhu Weiqiang Liu Regean Pitiya 《Earthquake Research Advances》 CSCD 2022年第1期44-55,共12页
Shallow conductive heterogeneity can lead to static shifts ain the apparent resistivity sounding curve of controlled-source audio-frequency magnetotellurics(CSAMT).The static effect will shift the apparent resistivity... Shallow conductive heterogeneity can lead to static shifts ain the apparent resistivity sounding curve of controlled-source audio-frequency magnetotellurics(CSAMT).The static effect will shift the apparent resistivity curves along with axial log-log coordinates.Such an effect,if not properly processed,can distort the resistivity of rock formation and the depth of interfaces,and even make the geological structures unrecognizable.In this paper,we discuss the reasons and characteristics of the static shift and summarize the previous studies regarding static shift correction.Then,we propose the Guided Image Filtering algorithm to suppress static shifts in CSAMT.In detail,we use the multi-window superposition method to superimpose 1D signals into a 2D matrix image,which is subsequently processed with Guided Image Filtering.In the synthetic model study and field examples,the Guided Image Filtering algorithm has effectively corrected and suppressed static shifts,and finally improved the precision of data interpretation. 展开更多
关键词 CSAMT Static shift Guided image filtering anti-interfereNCE
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Neural Cryptography with Fog Computing Network for Health Monitoring Using IoMT 被引量:1
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作者 G.Ravikumar K.Venkatachalam +2 位作者 Mohammed A.AlZain Mehedi Masud Mohamed Abouhawwash 《Computer Systems Science & Engineering》 SCIE EI 2023年第1期945-959,共15页
Sleep apnea syndrome(SAS)is a breathing disorder while a person is asleep.The traditional method for examining SAS is Polysomnography(PSG).The standard procedure of PSG requires complete overnight observation in a lab... Sleep apnea syndrome(SAS)is a breathing disorder while a person is asleep.The traditional method for examining SAS is Polysomnography(PSG).The standard procedure of PSG requires complete overnight observation in a laboratory.PSG typically provides accurate results,but it is expensive and time consuming.However,for people with Sleep apnea(SA),available beds and laboratories are limited.Resultantly,it may produce inaccurate diagnosis.Thus,this paper proposes the Internet of Medical Things(IoMT)framework with a machine learning concept of fully connected neural network(FCNN)with k-near-est neighbor(k-NN)classifier.This paper describes smart monitoring of a patient’s sleeping habit and diagnosis of SA using FCNN-KNN+average square error(ASE).For diagnosing SA,the Oxygen saturation(SpO2)sensor device is popularly used for monitoring the heart rate and blood oxygen level.This diagnosis information is securely stored in the IoMT fog computing network.Doctors can care-fully monitor the SA patient remotely on the basis of sensor values,which are efficiently stored in the fog computing network.The proposed technique takes less than 0.2 s with an accuracy of 95%,which is higher than existing models. 展开更多
关键词 Sleep apnea POLYSOMNOGRAPHY IOMT fog node security neural network KNN signature encryption sensor
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Blockchain-Enabled Secure and Privacy-Preserving Data Aggregation for Fog-Based ITS
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作者 Siguang Chen Li Yang +1 位作者 Yanhang Shi Qian Wang 《Computers, Materials & Continua》 SCIE EI 2023年第5期3781-3796,共16页
As an essential component of intelligent transportation systems(ITS),electric vehicles(EVs)can store massive amounts of electric power in their batteries and send power back to a charging station(CS)at peak hours to b... As an essential component of intelligent transportation systems(ITS),electric vehicles(EVs)can store massive amounts of electric power in their batteries and send power back to a charging station(CS)at peak hours to balance the power supply and generate profits.However,when the system collects the corresponding power data,several severe security and privacy issues are encountered.The identity and private injection data may be maliciously intercepted by network attackers and be tampered with to damage the services of ITS and smart grids.Existing approaches requiring high computational overhead render them unsuitable for the resource-constrained Internet of Things(IoT)environment.To address above problems,this paper proposes a blockchain-enabled secure and privacy-preserving data aggregation scheme for fog-based ITS.First,a fog computing and blockchain co-aware aggregation framework of power injection data is designed,which provides strong support for ITS to achieve secure and efficient power injection.Second,Paillier homomorphic encryption,the batch aggregation signature mechanism and a Bloom filter are effectively integrated with efficient aggregation of power injection data with security and privacy guarantees.In addition,the fine-grained homomorphic aggregation is designed for power injection data generated by all EVs,which provides solid data support for accurate power dispatching and supply management in ITS.Experiments show that the total computational cost is significantly reduced in the proposed scheme while providing security and privacy guarantees.The proposed scheme is more suitable for ITS with latency-sensitive applications and is also adapted to deploying devices with limited resources. 展开更多
关键词 Blockchain fog computing security PRIVACY-PRESERVING ITS
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Anti-interference Strategy of 20-Hi Cold Mill Automatic Gauge Control
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作者 ZHANG Zhen ZHU Bingquan CHEN Haifeng 《Instrumentation》 2022年第3期10-18,共9页
Automatic gauge control(AGC in the article)is the key technology of product thickness accuracy and flatness quality in modern cold rolling mill.Most traditional AGC control algorithms need stable external system condi... Automatic gauge control(AGC in the article)is the key technology of product thickness accuracy and flatness quality in modern cold rolling mill.Most traditional AGC control algorithms need stable external system conditions and hard to stabilize under complex interference that meets coverage requirements.This paper presents a new anti-interference strategy for AGC control of 20-Hi cold reversing mill.The proposed algorithm introduces a united dynamic weights algorithm of feed forward-mass flow to avoid the complex interference problem in AGC control,the relevant control strategy is provided to eliminate the adverse effects.At the same time,the D-value between feed forward-mass flow pre-computation and thickness measurement deviation is dynamic compared,the final gap position regulation is calculated by developing a set of united dynamic weights between feed forward control and mass flow control.Finally,the output of controllers is sent to actuator though a constant rate smoothing.The proposed strategy is compared with conventional AGC control on Experimental platform and project application,the results show that the proposed strategy is more stable than comparison method and majority of system uncertainty produced by mentioned interference is significantly eliminated. 展开更多
关键词 20-Hi Cold Mill Complex Interference AGC Control United Dynamic Weights anti-interfereNCE
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Latency-Aware Dynamic Second Offloading Service in SDN-Based Fog Architecture
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作者 Samah Ibrahim AlShathri Dina S.M.Hassan Samia Allaoua Chelloug 《Computers, Materials & Continua》 SCIE EI 2023年第4期1501-1526,共26页
Task offloading is a key strategy in Fog Computing (FC). Thedefinition of resource-constrained devices no longer applies to sensors andInternet of Things (IoT) embedded system devices alone. Smart and mobileunits can ... Task offloading is a key strategy in Fog Computing (FC). Thedefinition of resource-constrained devices no longer applies to sensors andInternet of Things (IoT) embedded system devices alone. Smart and mobileunits can also be viewed as resource-constrained devices if the power, cloudapplications, and data cloud are included in the set of required resources. Ina cloud-fog-based architecture, a task instance running on an end device mayneed to be offloaded to a fog node to complete its execution. However, ina busy network, a second offloading decision is required when the fog nodebecomes overloaded. The possibility of offloading a task, for the second time,to a fog or a cloud node depends to a great extent on task importance, latencyconstraints, and required resources. This paper presents a dynamic service thatdetermines which tasks can endure a second offloading. The task type, latencyconstraints, and amount of required resources are used to select the offloadingdestination node. This study proposes three heuristic offloading algorithms.Each algorithm targets a specific task type. An overloaded fog node can onlyissue one offloading request to execute one of these algorithms accordingto the task offloading priority. Offloading requests are sent to a SoftwareDefined Networking (SDN) controller. The fog node and controller determinethe number of offloaded tasks. Simulation results show that the average timerequired to select offloading nodes was improved by 33% when compared tothe dynamic fog-to-fog offloading algorithm. The distribution of workloadconverges to a uniform distribution when offloading latency-sensitive nonurgenttasks. The lowest offloading priority is assigned to latency-sensitivetasks with hard deadlines. At least 70% of these tasks are offloaded to fognodes that are one to three hops away from the overloaded node. 展开更多
关键词 fog computing offloading algorithm latency-aware software defined networking SDN
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Levy Flight Firefly Based Efficient Resource Allocation for Fog Environment
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作者 Anu Anita Singhrova 《Intelligent Automation & Soft Computing》 SCIE 2023年第7期199-219,共21页
Fog computing is an emergent and powerful computing paradigm to serve latency-sensitive applications by executing internet of things(IoT)appli-cations in the proximity of the network.Fog computing offers computational... Fog computing is an emergent and powerful computing paradigm to serve latency-sensitive applications by executing internet of things(IoT)appli-cations in the proximity of the network.Fog computing offers computational and storage services between cloud and terminal devices.However,an efficient resource allocation to execute the IoT applications in a fog environment is still challenging due to limited resource availability and low delay requirement of services.A large number of heterogeneous shareable resources makes fog computing a complex environment.In the sight of these issues,this paper has proposed an efficient levy flight firefly-based resource allocation technique.The levy flight algorithm is a metaheuristic algorithm.It offers high efficiency and success rate because of its longer step length and fast convergence rate.Thus,it treats global optimization problems more efficiently and naturally.A system framework for fog computing is presented,followed by the proposed resource allocation scheme in the fog computing environment.Experimental evaluation and comparison with the firefly algorithm(FA),particle swarm optimization(PSO),genetic algorithm(GA)and hybrid algorithm using GA and PSO(GAPSO)have been conducted to validate the effectiveness and efficiency of the proposed algorithm.Simulation results show that the proposed algorithm performs efficient resource allocation and improves the quality of service(QoS).The proposed algorithm reduces average waiting time,average execution time,average turnaround time,processing cost and energy consumption and increases resource utilization and task success rate compared to FA,GAPSO,PSO and GA. 展开更多
关键词 fog computing resource allocation FIREFLY IOT CLOUD
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