Background:The analysis and prediction of pancreaticobiliary reflux(PBR)play a crucial role in planning surgical interventions for hepato-biliary-pancreatic diseases,considering the uncertain mechanism behind it.Howev...Background:The analysis and prediction of pancreaticobiliary reflux(PBR)play a crucial role in planning surgical interventions for hepato-biliary-pancreatic diseases,considering the uncertain mechanism behind it.However,current practices are limited by fragmented clinical observations,making it challenging to visualize the complex phenomenon in the pancreaticobiliary junction(PBJ)through imaging and radiography experiments.This study aimed to comprehensively describe the retrograde flow characteristics in various PBR scenarios and assess the factors leading to PBR using simulations based on idealized geometry and boundary conditions.Methods:By Cadence Pointwise,we developed a computational fluid dynamics(CFD)model using an idealized PBJ system.Standard parameters such as pressure and viscosity were applied,along with typical assumptions relevant to fluid dynamic modeling.Subsequently,based on the aforementioned basic idealized model,we analyzed 8 hypothetical PBR conditions,covering a range of high(shorter)and low(longer)values or different positions for each specific parameter,at a representative stage of a peristaltic propagation cycle of the Oddi's sphincter.Results:We modeled a two-dimensional PBJ with the propagation of a peristaltic wave.These findings demonstrated that the shortened septum,the extended ampulla,the increased wavelength and enhanced amplitude of the Oddi's sphincterial peristalsis,the widened diameter difference and the increased pressure difference between the common bile duct(CBD)and the main pancreatic duct(MPD),as well as the gravitational effect(position),strongly impacted PBR,while the viscosity of bile and pancreatic juice had a weaker influence.Additionally,an inequality incorporating these risk factors was developed for the evaluation of whether reflux occurs.Conclusions:Numerical simulation can be used to describe the reflux flow field,offering the possibility to visualize and analyze PBR,which has the potential to significantly revolutionize the understanding of PBR and improve clinical decision-making.Future work should focus on bridging the gap between CFD and clinical practice.展开更多
Ankle injuries account for more than 25%of sports-related injuries.However,there is a lack of computational mechanics modeling and assessment tools for the ligament loading mechanism(LLM)caused by ankle injury.This st...Ankle injuries account for more than 25%of sports-related injuries.However,there is a lack of computational mechanics modeling and assessment tools for the ligament loading mechanism(LLM)caused by ankle injury.This study combines medical imaging data to construct the subject-specific ankle musculoskeletal model,which considers the subject's individualized characteristics and ligamentous attributes.Furthermore,we developed the structural constitutive model to restore the nonlinear short-term viscoelastic properties of the ligament-dense connective tissue,which can more realistically revert the LLM and reveal the mechanical properties of ankle injury.Based on the computational ligament mechanics(CLM)model,we developed a deep learning-based prediction model to predict LLM by CLM data-driven modeling.The modeling simulation results are highly consistent with the calculation results from the dual fluoroscopic imaging system,which demonstrated that the CLM model has high accuracy.The data-driven modeling performs exceptionally well in predicting ligament loading forces.The findings indicate that the constructed CLM data-driven model has the potential to enhance the accuracy and safety of ankle rehabilitation robots,while also providing personalized,dynamically adjusted rehabilitation training programs.The proposed comprehensive solutions would bring benefits to more patients with sports injuries and the general rehabilitation population,and promote the development and advancement of the research field of CLM and biomechanical variable prediction.展开更多
针对大型储罐除锈机器人在立面作业过程中易受到风力扰动、曲率突变导致轨迹跟踪精度下降的问题,提出一种基于模糊模型预测控制(fuzzy model predictive control,Fuzzy-MPC)策略。首先,构建四轮机器人运动学模型并离散化,得出一个采样...针对大型储罐除锈机器人在立面作业过程中易受到风力扰动、曲率突变导致轨迹跟踪精度下降的问题,提出一种基于模糊模型预测控制(fuzzy model predictive control,Fuzzy-MPC)策略。首先,构建四轮机器人运动学模型并离散化,得出一个采样周期内的线性离散方程。建立预测模型与多目标优化函数,采用二次优化求最优解。通过对位置误差与航向角误差进行模糊归一化处理,并将其作为模糊控制器的输入变量。采用改进型加权中心平均法进行解模糊计算,输出自适应调整的预测步长、控制步长及权重矩阵参数,实现对MPC控制器参数的实时优化。采用MATLAB/Simulink进行仿真验证,结果表明所提出的模糊MPC方法相较于传统MPC能使位移误差减少49%、误差峰值减少14.65%,航向角误差减少46.7%、误差峰值减少17.4%,验证了所提出的Fuzzy-MPC算法的有效性,为爬壁机器人高精度轨迹跟踪控制提供有效可行的优化策略。展开更多
The global surge in Artificial Intelligence(AI)has been triggered by the impressive performance of deep-learning models based on the Transformer architecture.However,the efficacy of such models is increasingly depende...The global surge in Artificial Intelligence(AI)has been triggered by the impressive performance of deep-learning models based on the Transformer architecture.However,the efficacy of such models is increasingly dependent on the volume and quality of data.Data are often distributed across institutions and companies,making cross-organizational data transfer vulnerable to privacy breaches and subject to privacy laws and trade secret regulations.These privacy and security concerns continue to pose major challenges to collaborative training and inference in multi-source data environments.These challenges are particularly significant for Transformer models,where the complex internal encryption computations drastically reduce computational efficiency,ultimately threatening the model's practical applicability.We hence introduce Secformer,an innovative architecture specifically designed to protect the privacy of Transformer-like models.Secformer separates the encoder and decoder modules,enabling the decomposition of computation flows in Transformer-like models and their efficient mapping to Multi-Party Computation(MPC)protocols.This design effectively addresses privacy leakage issues during the collaborative computation process of Transformer models.To prevent performance degradation caused by encrypted attention modules,we propose a modular design strategy that optimizes high-level components by reconstructing low-level operators.We further analyze the security of Secformer's core components,presenting security definitions and formal proofs.We construct a library of fundamental operators and core modules using atomic-level component designs as the basic building blocks for encoders and decoders.Moreover,these components can serve as foundational operators for other Transformer-like models.Extensive experimental evaluations demonstrate Secformer's excellent performance while preserving privacy and offering universal adaptability for Transformer-like models.展开更多
This study presents a computational modeling framework for efficient and secure computation offloading in Internet of Things(IoT)-enabled smart contract systems.The integration of IoT,edge computing,and blockchain int...This study presents a computational modeling framework for efficient and secure computation offloading in Internet of Things(IoT)-enabled smart contract systems.The integration of IoT,edge computing,and blockchain introduces significant challenges,including limited device capacity,high verification cost,and scalability constraints.Existing blockchain verification approaches depend on computationally intensive cryptographic operations that are inefficient for resource-constrained IoT devices,resulting in increased latency,energy consumption,and transaction costs.To address these issues,this study proposes the Zero-Knowledge Fuzzy Logic Offloading and Rollup(Z-FLOR)framework,an adaptive and energy-efficient model designed to enable secure and verifiable computation in IoT-based smart contract systems.The proposed framework integrates three key components.First,a zero-knowledge proof-based verification model using the Grothl6 zkSNARK module generates compact and privacy-preserving proofs that enable fast and reliable verification.Second,a Fuzzy Logic-Driven Energy-Aware Offloading module dynamically allocates computational tasks between IoT devices,edge servers,and cloud platforms based on energy availability,network delay,and device reliability.Third,an Optimistic Rollup Verification module aggregates proofs off-chain and submits them in batches to reduce gas costs and enhance scalability.Extensive simulation and experimental evaluation across diverse IoT scenarios demonstrate the effectiveness of the proposed computational framework.Results indicate that Z-FLOR achieves 99.7%verification accuracy and 98.9%proof compression efficiency,while gas cost analysis indicates gas cost reductions in the range of 80%-98%.Z-FLOR additionally achieves a 44.0%reduction in latency,5l.0%savings in gas costs,and 38.0%energy consumption compared to baseline approaches.These findings highlight the capability of the proposed approach to serve as a scalable and energy-efficient modeling solution for secure IoT smart contract execution in decentralized environments.展开更多
In the field of edge computing,achieving low-latency computational task offloading with limited resources is a critical research challenge,particularly in resource-constrained and latency-sensitive vehicular network e...In the field of edge computing,achieving low-latency computational task offloading with limited resources is a critical research challenge,particularly in resource-constrained and latency-sensitive vehicular network environments where rapid response is mandatory for safety-critical applications.In scenarios where edge servers are sparsely deployed,the lack of coordination and information sharing often leads to load imbalance,thereby increasing system latency.Furthermore,in regions without edge server coverage,tasks must be processed locally,which further exacerbates latency issues.To address these challenges,we propose a novel and efficient Deep Reinforcement Learning(DRL)-based approach aimed at minimizing average task latency.The proposed method incorporates three offloading strategies:local computation,direct offloading to the edge server in local region,and device-to-device(D2D)-assisted offloading to edge servers in other regions.We formulate the task offloading process as a complex latency minimization optimization problem.To solve it,we propose an advanced algorithm based on the Dueling Double Deep Q-Network(D3QN)architecture and incorporating the Prioritized Experience Replay(PER)mechanism.Experimental results demonstrate that,compared with existing offloading algorithms,the proposed method significantly reduces average task latency,enhances user experience,and offers an effective strategy for latency optimization in future edge computing systems under dynamic workloads.展开更多
Vehicle Edge Computing(VEC)and Cloud Computing(CC)significantly enhance the processing efficiency of delay-sensitive and computation-intensive applications by offloading compute-intensive tasks from resource-constrain...Vehicle Edge Computing(VEC)and Cloud Computing(CC)significantly enhance the processing efficiency of delay-sensitive and computation-intensive applications by offloading compute-intensive tasks from resource-constrained onboard devices to nearby Roadside Unit(RSU),thereby achieving lower delay and energy consumption.However,due to the limited storage capacity and energy budget of RSUs,it is challenging to meet the demands of the highly dynamic Internet of Vehicles(IoV)environment.Therefore,determining reasonable service caching and computation offloading strategies is crucial.To address this,this paper proposes a joint service caching scheme for cloud-edge collaborative IoV computation offloading.By modeling the dynamic optimization problem using Markov Decision Processes(MDP),the scheme jointly optimizes task delay,energy consumption,load balancing,and privacy entropy to achieve better quality of service.Additionally,a dynamic adaptive multi-objective deep reinforcement learning algorithm is proposed.Each Double Deep Q-Network(DDQN)agent obtains rewards for different objectives based on distinct reward functions and dynamically updates the objective weights by learning the value changes between objectives using Radial Basis Function Networks(RBFN),thereby efficiently approximating the Pareto-optimal decisions for multiple objectives.Extensive experiments demonstrate that the proposed algorithm can better coordinate the three-tier computing resources of cloud,edge,and vehicles.Compared to existing algorithms,the proposed method reduces task delay and energy consumption by 10.64%and 5.1%,respectively.展开更多
The limited onboard cache and computing resources significantly constrain the computational service capabilities of individual edge satellites in hotspot regions.To address this challenge,we propose a twotier cloud-ed...The limited onboard cache and computing resources significantly constrain the computational service capabilities of individual edge satellites in hotspot regions.To address this challenge,we propose a twotier cloud-edge computing architecture that organizes edge satellites and their associated ground clouds into multiple collaborative domains.Within each domain,we formulate a joint optimization problem for computation offloading and service downloading under the constraints of edge satellites’service deployment and caching space,aiming to minimize the sum of weighted energy consumption and latency.The originally non-convex problem is transformed into a more tractable convex optimization formulation through variable relaxation.Subsequently,we develop an alternating direction method of multipliers(ADMM)-based distributed optimization framework that enables cooperative decision-making among domain satellites for the optimization of computational offloading,service downloading,and service deleting variables.Additionally,we propose an innovative binary variable recovery algorithm that ensures feasible conversion from continuous solutions to discrete decision variables while preserving constraint satisfaction.Extensive simulations demonstrate that our approach achieves lower task execution cost and packet loss rate compared with benchmarks.展开更多
Intelligent machine tools operating in continuous machining environments are commonly influenced by the coupled effects of multi-component degradation and updates in machining tasks.These factors result in the generat...Intelligent machine tools operating in continuous machining environments are commonly influenced by the coupled effects of multi-component degradation and updates in machining tasks.These factors result in the generation of vast multi-source sensor data streams and numerous computational tasks with interdependent data relationships.The stringent real-time constraints and intricate dependency structures present considerable challenges to traditional single-mode computational frameworks.Furthermore,there is a growing demand for computational offloading solutions in intelligent machine tools that extend beyond merely optimizing latency.These solutions must also address energy management for sustainable manufacturing and ensure security to protect sensitive industrial data.This paper introduces an adaptive hybrid edge-cloud collaborative offloading mechanism that combines single-edge-cloud collaboration with multi-edge-cloud collaboration.This mechanism is capable of dynamically switching between collaborative modes based on the status of computational nodes,task characteristics,dependency complexity,and resource availability,ultimately facilitating low-latency,energy-efficient,and secure task processing.A novel hybrid hyper-heuristic algorithm has been developed to address largescale task allocation challenges in heterogeneous edge-cloud environments,enabling the flexible allocation of computational resources and performance optimization.Extensive experiments indicate that the proposed approach achieves average enhancements of 27.36%in task processing time and 7.89%in energy efficiency when compared to state-of-the-art techniques,all while maintaining superior security performance.Validation through case studies on a digital twin gantry five-axis machining center illustrates that the mechanism effectively coordinates task execution across multi-source concurrent data processing,complex dependency task collaboration,high-computational machine learning workloads,and continuous batch task deployment scenarios,achieving a 37.03%reduction in latency and a 25.93%optimization in energy use relative to previous generation collaboration methods.These results provide both theoretical and technical backing for sustainable and secure computational offloading in intelligent machine tools,thereby contributing to the evolution of next-generation smart manufacturing systems.展开更多
基金supported by grants from the Key Specialty Construction Project of Shanghai Pudong New Area Health Commission(PWZzk2022-17)the Featured Clinical Discipline Project of Shanghai Pudong District(PWYts2021-06)+2 种基金the Fund from Shanghai East Hospital(DFLC2022019,DFRC2018014 and 2024-DFZD-005DS)Hutchison Research Fund(2025HH-015)the Science and Technology Development Project of Medical and Health of Shandong Province(202010000131 and 202104070065)。
摘要Background:The analysis and prediction of pancreaticobiliary reflux(PBR)play a crucial role in planning surgical interventions for hepato-biliary-pancreatic diseases,considering the uncertain mechanism behind it.However,current practices are limited by fragmented clinical observations,making it challenging to visualize the complex phenomenon in the pancreaticobiliary junction(PBJ)through imaging and radiography experiments.This study aimed to comprehensively describe the retrograde flow characteristics in various PBR scenarios and assess the factors leading to PBR using simulations based on idealized geometry and boundary conditions.Methods:By Cadence Pointwise,we developed a computational fluid dynamics(CFD)model using an idealized PBJ system.Standard parameters such as pressure and viscosity were applied,along with typical assumptions relevant to fluid dynamic modeling.Subsequently,based on the aforementioned basic idealized model,we analyzed 8 hypothetical PBR conditions,covering a range of high(shorter)and low(longer)values or different positions for each specific parameter,at a representative stage of a peristaltic propagation cycle of the Oddi's sphincter.Results:We modeled a two-dimensional PBJ with the propagation of a peristaltic wave.These findings demonstrated that the shortened septum,the extended ampulla,the increased wavelength and enhanced amplitude of the Oddi's sphincterial peristalsis,the widened diameter difference and the increased pressure difference between the common bile duct(CBD)and the main pancreatic duct(MPD),as well as the gravitational effect(position),strongly impacted PBR,while the viscosity of bile and pancreatic juice had a weaker influence.Additionally,an inequality incorporating these risk factors was developed for the evaluation of whether reflux occurs.Conclusions:Numerical simulation can be used to describe the reflux flow field,offering the possibility to visualize and analyze PBR,which has the potential to significantly revolutionize the understanding of PBR and improve clinical decision-making.Future work should focus on bridging the gap between CFD and clinical practice.
基金supported by Zhejiang Provincial Natural Science Foundation of China for Distinguished Young Scholars(Grant No.LR22A020002)Zhejiang Provincial Key Research and Development Program of China(Grant No.2023C03197)+2 种基金Ningbo Key R&D Program(Grant No.2022Z196)the National Key Research and Development Program of China(Grant No.2024YFC3607305)Zhejiang Rehabilitation Medical Association Scientific Research Special Fund(Grant No.ZKKY2023001).
摘要Ankle injuries account for more than 25%of sports-related injuries.However,there is a lack of computational mechanics modeling and assessment tools for the ligament loading mechanism(LLM)caused by ankle injury.This study combines medical imaging data to construct the subject-specific ankle musculoskeletal model,which considers the subject's individualized characteristics and ligamentous attributes.Furthermore,we developed the structural constitutive model to restore the nonlinear short-term viscoelastic properties of the ligament-dense connective tissue,which can more realistically revert the LLM and reveal the mechanical properties of ankle injury.Based on the computational ligament mechanics(CLM)model,we developed a deep learning-based prediction model to predict LLM by CLM data-driven modeling.The modeling simulation results are highly consistent with the calculation results from the dual fluoroscopic imaging system,which demonstrated that the CLM model has high accuracy.The data-driven modeling performs exceptionally well in predicting ligament loading forces.The findings indicate that the constructed CLM data-driven model has the potential to enhance the accuracy and safety of ankle rehabilitation robots,while also providing personalized,dynamically adjusted rehabilitation training programs.The proposed comprehensive solutions would bring benefits to more patients with sports injuries and the general rehabilitation population,and promote the development and advancement of the research field of CLM and biomechanical variable prediction.
摘要针对大型储罐除锈机器人在立面作业过程中易受到风力扰动、曲率突变导致轨迹跟踪精度下降的问题,提出一种基于模糊模型预测控制(fuzzy model predictive control,Fuzzy-MPC)策略。首先,构建四轮机器人运动学模型并离散化,得出一个采样周期内的线性离散方程。建立预测模型与多目标优化函数,采用二次优化求最优解。通过对位置误差与航向角误差进行模糊归一化处理,并将其作为模糊控制器的输入变量。采用改进型加权中心平均法进行解模糊计算,输出自适应调整的预测步长、控制步长及权重矩阵参数,实现对MPC控制器参数的实时优化。采用MATLAB/Simulink进行仿真验证,结果表明所提出的模糊MPC方法相较于传统MPC能使位移误差减少49%、误差峰值减少14.65%,航向角误差减少46.7%、误差峰值减少17.4%,验证了所提出的Fuzzy-MPC算法的有效性,为爬壁机器人高精度轨迹跟踪控制提供有效可行的优化策略。
基金supported by the National Natural Science Foundation of China under Grant 62471205in part by the Yunnan Fundamental Research Projects under Grant 202301AV070003in part by the Major Science and Technology Projects in Yunnan Province under Grant 202302AG050009。
摘要The global surge in Artificial Intelligence(AI)has been triggered by the impressive performance of deep-learning models based on the Transformer architecture.However,the efficacy of such models is increasingly dependent on the volume and quality of data.Data are often distributed across institutions and companies,making cross-organizational data transfer vulnerable to privacy breaches and subject to privacy laws and trade secret regulations.These privacy and security concerns continue to pose major challenges to collaborative training and inference in multi-source data environments.These challenges are particularly significant for Transformer models,where the complex internal encryption computations drastically reduce computational efficiency,ultimately threatening the model's practical applicability.We hence introduce Secformer,an innovative architecture specifically designed to protect the privacy of Transformer-like models.Secformer separates the encoder and decoder modules,enabling the decomposition of computation flows in Transformer-like models and their efficient mapping to Multi-Party Computation(MPC)protocols.This design effectively addresses privacy leakage issues during the collaborative computation process of Transformer models.To prevent performance degradation caused by encrypted attention modules,we propose a modular design strategy that optimizes high-level components by reconstructing low-level operators.We further analyze the security of Secformer's core components,presenting security definitions and formal proofs.We construct a library of fundamental operators and core modules using atomic-level component designs as the basic building blocks for encoders and decoders.Moreover,these components can serve as foundational operators for other Transformer-like models.Extensive experimental evaluations demonstrate Secformer's excellent performance while preserving privacy and offering universal adaptability for Transformer-like models.
基金by the Korea Institute of Energy Technology Evaluation and Planning(KETEP)grant funded by the Korea government(MOTIE)(RS-2023-00303559,Study on developing cyber-physical attack response system and security management system to maximize real-time distributed resource availability,50%)by the Institute of Information&Communications Technology Planning&Evaluation(IITP)grant funded by the Korea government(MSIT)(RS 2024-00400955,Development of Core Security Technology to Respond to International Smart Ship Regulations,50%).
摘要This study presents a computational modeling framework for efficient and secure computation offloading in Internet of Things(IoT)-enabled smart contract systems.The integration of IoT,edge computing,and blockchain introduces significant challenges,including limited device capacity,high verification cost,and scalability constraints.Existing blockchain verification approaches depend on computationally intensive cryptographic operations that are inefficient for resource-constrained IoT devices,resulting in increased latency,energy consumption,and transaction costs.To address these issues,this study proposes the Zero-Knowledge Fuzzy Logic Offloading and Rollup(Z-FLOR)framework,an adaptive and energy-efficient model designed to enable secure and verifiable computation in IoT-based smart contract systems.The proposed framework integrates three key components.First,a zero-knowledge proof-based verification model using the Grothl6 zkSNARK module generates compact and privacy-preserving proofs that enable fast and reliable verification.Second,a Fuzzy Logic-Driven Energy-Aware Offloading module dynamically allocates computational tasks between IoT devices,edge servers,and cloud platforms based on energy availability,network delay,and device reliability.Third,an Optimistic Rollup Verification module aggregates proofs off-chain and submits them in batches to reduce gas costs and enhance scalability.Extensive simulation and experimental evaluation across diverse IoT scenarios demonstrate the effectiveness of the proposed computational framework.Results indicate that Z-FLOR achieves 99.7%verification accuracy and 98.9%proof compression efficiency,while gas cost analysis indicates gas cost reductions in the range of 80%-98%.Z-FLOR additionally achieves a 44.0%reduction in latency,5l.0%savings in gas costs,and 38.0%energy consumption compared to baseline approaches.These findings highlight the capability of the proposed approach to serve as a scalable and energy-efficient modeling solution for secure IoT smart contract execution in decentralized environments.
基金supported by the National Natural Science Foundation of China(62202215)Liaoning Province Applied Basic Research Program(Youth Special Project,2023JH2/101600038)+4 种基金Shenyang Youth Science and Technology Innovation Talent Support Program(RC220458)Guangxuan Program of Shenyang Ligong University(SYLUGXRC202216)the Basic Research Special Funds for Undergraduate Universities in Liaoning Province(LJ212410144067)the Natural Science Foundation of Liaoning Province(2024-MS-113)the science and technology funds from Liaoning Education Department(LJKZ0242).
摘要In the field of edge computing,achieving low-latency computational task offloading with limited resources is a critical research challenge,particularly in resource-constrained and latency-sensitive vehicular network environments where rapid response is mandatory for safety-critical applications.In scenarios where edge servers are sparsely deployed,the lack of coordination and information sharing often leads to load imbalance,thereby increasing system latency.Furthermore,in regions without edge server coverage,tasks must be processed locally,which further exacerbates latency issues.To address these challenges,we propose a novel and efficient Deep Reinforcement Learning(DRL)-based approach aimed at minimizing average task latency.The proposed method incorporates three offloading strategies:local computation,direct offloading to the edge server in local region,and device-to-device(D2D)-assisted offloading to edge servers in other regions.We formulate the task offloading process as a complex latency minimization optimization problem.To solve it,we propose an advanced algorithm based on the Dueling Double Deep Q-Network(D3QN)architecture and incorporating the Prioritized Experience Replay(PER)mechanism.Experimental results demonstrate that,compared with existing offloading algorithms,the proposed method significantly reduces average task latency,enhances user experience,and offers an effective strategy for latency optimization in future edge computing systems under dynamic workloads.
基金supported by Key Science and Technology Program of Henan Province,China(Grant Nos.242102210147,242102210027)Fujian Province Young and Middle aged Teacher Education Research Project(Science and Technology Category)(No.JZ240101)(Corresponding author:Dong Yuan).
摘要Vehicle Edge Computing(VEC)and Cloud Computing(CC)significantly enhance the processing efficiency of delay-sensitive and computation-intensive applications by offloading compute-intensive tasks from resource-constrained onboard devices to nearby Roadside Unit(RSU),thereby achieving lower delay and energy consumption.However,due to the limited storage capacity and energy budget of RSUs,it is challenging to meet the demands of the highly dynamic Internet of Vehicles(IoV)environment.Therefore,determining reasonable service caching and computation offloading strategies is crucial.To address this,this paper proposes a joint service caching scheme for cloud-edge collaborative IoV computation offloading.By modeling the dynamic optimization problem using Markov Decision Processes(MDP),the scheme jointly optimizes task delay,energy consumption,load balancing,and privacy entropy to achieve better quality of service.Additionally,a dynamic adaptive multi-objective deep reinforcement learning algorithm is proposed.Each Double Deep Q-Network(DDQN)agent obtains rewards for different objectives based on distinct reward functions and dynamically updates the objective weights by learning the value changes between objectives using Radial Basis Function Networks(RBFN),thereby efficiently approximating the Pareto-optimal decisions for multiple objectives.Extensive experiments demonstrate that the proposed algorithm can better coordinate the three-tier computing resources of cloud,edge,and vehicles.Compared to existing algorithms,the proposed method reduces task delay and energy consumption by 10.64%and 5.1%,respectively.
基金supported by the National Natural Science Foundation of China under Grant 62371098.
摘要The limited onboard cache and computing resources significantly constrain the computational service capabilities of individual edge satellites in hotspot regions.To address this challenge,we propose a twotier cloud-edge computing architecture that organizes edge satellites and their associated ground clouds into multiple collaborative domains.Within each domain,we formulate a joint optimization problem for computation offloading and service downloading under the constraints of edge satellites’service deployment and caching space,aiming to minimize the sum of weighted energy consumption and latency.The originally non-convex problem is transformed into a more tractable convex optimization formulation through variable relaxation.Subsequently,we develop an alternating direction method of multipliers(ADMM)-based distributed optimization framework that enables cooperative decision-making among domain satellites for the optimization of computational offloading,service downloading,and service deleting variables.Additionally,we propose an innovative binary variable recovery algorithm that ensures feasible conversion from continuous solutions to discrete decision variables while preserving constraint satisfaction.Extensive simulations demonstrate that our approach achieves lower task execution cost and packet loss rate compared with benchmarks.
基金funded by the National Natural Science Foundation of China(U23B20104)the Innovation Consortium Project of Machine Tools and Moulds in Dongguan(20251201500012)+1 种基金the Jilin Province Science and Technology Development Plan(YDZJ202401314ZYTS)the Integrated Project of the National Natural Science Foundation of China(U24B6007)。
摘要Intelligent machine tools operating in continuous machining environments are commonly influenced by the coupled effects of multi-component degradation and updates in machining tasks.These factors result in the generation of vast multi-source sensor data streams and numerous computational tasks with interdependent data relationships.The stringent real-time constraints and intricate dependency structures present considerable challenges to traditional single-mode computational frameworks.Furthermore,there is a growing demand for computational offloading solutions in intelligent machine tools that extend beyond merely optimizing latency.These solutions must also address energy management for sustainable manufacturing and ensure security to protect sensitive industrial data.This paper introduces an adaptive hybrid edge-cloud collaborative offloading mechanism that combines single-edge-cloud collaboration with multi-edge-cloud collaboration.This mechanism is capable of dynamically switching between collaborative modes based on the status of computational nodes,task characteristics,dependency complexity,and resource availability,ultimately facilitating low-latency,energy-efficient,and secure task processing.A novel hybrid hyper-heuristic algorithm has been developed to address largescale task allocation challenges in heterogeneous edge-cloud environments,enabling the flexible allocation of computational resources and performance optimization.Extensive experiments indicate that the proposed approach achieves average enhancements of 27.36%in task processing time and 7.89%in energy efficiency when compared to state-of-the-art techniques,all while maintaining superior security performance.Validation through case studies on a digital twin gantry five-axis machining center illustrates that the mechanism effectively coordinates task execution across multi-source concurrent data processing,complex dependency task collaboration,high-computational machine learning workloads,and continuous batch task deployment scenarios,achieving a 37.03%reduction in latency and a 25.93%optimization in energy use relative to previous generation collaboration methods.These results provide both theoretical and technical backing for sustainable and secure computational offloading in intelligent machine tools,thereby contributing to the evolution of next-generation smart manufacturing systems.