The rise of time-sensitive applications with broad geographical scope drives the development of time-sensitive networking(TSN)from intra-domain to inter-domain to ensure overall end-to-end connectivity requirements in...The rise of time-sensitive applications with broad geographical scope drives the development of time-sensitive networking(TSN)from intra-domain to inter-domain to ensure overall end-to-end connectivity requirements in heterogeneous deployments.When multiple TSN networks interconnect over non-TSN networks,all devices in the network need to be syn-chronized by sharing a uniform time reference.How-ever,most non-TSN networks are best-effort.Path delay asymmetry and random noise accumulation can introduce unpredictable time errors during end-to-end time synchronization.These factors can degrade syn-chronization performance.Therefore,cross-domain time synchronization becomes a challenging issue for multiple TSN networks interconnected by non-TSN networks.This paper presents a cross-domain time synchronization scheme that follows the software-defined TSN(SD-TSN)paradigm.It utilizes a com-bined control plane constructed by a coordinate con-troller and a domain controller for centralized control and management of cross-domain time synchroniza-tion.The general operation flow of the cross-domain time synchronization process is designed.The mecha-nism of cross-domain time synchronization is revealed by introducing a synchronization model and an error compensation method.A TSN cross-domain proto-type testbed is constructed for verification.Results show that the scheme can achieve end-to-end high-precision time synchronization with accuracy and sta-bility.展开更多
Accurate time synchronization is fundamental to the correct and efficient operation of Wireless Sensor Networks(WSNs),especially in security-critical,time-sensitive applications.However,most existing protocols degrade...Accurate time synchronization is fundamental to the correct and efficient operation of Wireless Sensor Networks(WSNs),especially in security-critical,time-sensitive applications.However,most existing protocols degrade substantially under malicious interference.We introduce iSTSP,an Intelligent and Secure Time Synchronization Protocol that implements a four-stage defense pipeline to ensure robust,precise synchronization even in hostile environments:(1)trust preprocessing that filters node participation using behavioral trust scoring;(2)anomaly isolation employing a lightweight autoencoder to detect and excise malicious nodes in real time;(3)reliability-weighted consensus that prioritizes high-trust nodes during time aggregation;and(4)convergence-optimized synchronization that dynamically adjusts parameters using theoretical stability bounds.We provide rigorous convergence analysis including a closed-form expression for convergence time,and validate the protocol through both simulations and realworld experiments on a controlled 16-node testbed.Under Sybil attacks with five malicious nodes within this testbed,iSTSP maintains synchronization error increases under 12%and achieves a rapid convergence.Compared to state-ofthe-art protocols like TPSN,SE-FTSP,and MMAR-CTS,iSTSP offers 60%faster detection,broader threat coverage,and more than 7 times lower synchronization error,with a modest 9.3%energy overhead over 8 h.We argue this is an acceptable trade-off for mission-critical deployments requiring guaranteed security.These findings demonstrate iSTSP’s potential as a reliable solution for secure WSN synchronization and motivate future work on large-scale IoT deployments and integration with energy-efficient communication protocols.展开更多
Time-Sensitive Network(TSN)with deterministic transmission capability is increasingly used in many emerging fields.It mainly guarantees the Quality of Service(QoS)of applications with strict requirements on time and s...Time-Sensitive Network(TSN)with deterministic transmission capability is increasingly used in many emerging fields.It mainly guarantees the Quality of Service(QoS)of applications with strict requirements on time and security.One of the core features of TSN is traffic scheduling with bounded low delay in the network.However,traffic scheduling schemes in TSN are usually synthesized offline and lack dynamism.To implement incremental scheduling of newly arrived traffic in TSN,we propose a Dynamic Response Incremental Scheduling(DR-IS)method for time-sensitive traffic and deploy it on a software-defined time-sensitive network architecture.Under the premise of meeting the traffic scheduling requirements,we adopt two modes,traffic shift and traffic exchange,to dynamically adjust the time slot injection position of the traffic in the original scheme,and determine the sending offset time of the new timesensitive traffic to minimize the global traffic transmission jitter.The evaluation results show that DRIS method can effectively control the large increase of traffic transmission jitter in incremental scheduling without affecting the transmission delay,thus realizing the dynamic incremental scheduling of time-sensitive traffic in TSN.展开更多
In the upcoming sixth-generation(6G)era,the demand for constructing a wide-area time-sensitive Internet of Things(IoT)continues to increase.As conventional cellular technologies are difficult to directly use for wide-...In the upcoming sixth-generation(6G)era,the demand for constructing a wide-area time-sensitive Internet of Things(IoT)continues to increase.As conventional cellular technologies are difficult to directly use for wide-area time-sensitive IoT,it is beneficial to use non-terrestrial infrastructures,including satellites and unmanned aerial vehicles(UAVs).Thus,we can build a non-terrestrial network(NTN)using a cell-free architecture.Driven by the time-sensitive requirements and uneven distribution of IoT devices,the NTN must be empowered using mobile edge computing(MEC)while providing oasisoriented on-demand coverage for devices.Nevertheless,communication and MEC systems are coupled with each other under the influence of a complex propagation environment in the MEC-empowered NTN,which makes it difficult to coordinate the resources.In this study,we propose a process-oriented framework to design communication and MEC systems in a time-division manner.In this framework,large-scale channel state information(CSI)is used to characterize the complex propagation environment at an affordable cost,where a nonconvex latency minimization problem is formulated.Subsequently,the approximated problem is provided,and it can be decomposed into sub-problems.These sub-problems are then solved iteratively.The simulation results demonstrated the superiority of the proposed process-oriented scheme over other algorithms,implied that the payload deployments of UAVs should be appropriately predesigned to improve the efficiency of using resources,and confirmed that it is advantageous to integrate NTN with MEC for wide-area time-sensitive IoT.展开更多
To improve the effect of destroying time-sensitive target （TST）, a method of operational effectiveness evaluation is presented and some influential factors are analyzed based on the combat flow of system for destroy...To improve the effect of destroying time-sensitive target （TST）, a method of operational effectiveness evaluation is presented and some influential factors are analyzed based on the combat flow of system for destroying TST. Considering the possible operation modes of the system, a waved operation mode and a continuous operation mode are put forward at first. At the same time, some relative formulas are modified. In examples, the influential factors and operation modes are analyzed based on the system effectiveness. From simulation results, some design and operation strategies of the system for destroying time sensitive targets are concluded, which benefit to the improvement of the system effectiveness.展开更多
Time-sensitive networking(TSN)is an important research area for updating the infrastructure of industrial Internet of Things.As a product of the integration of the operation technology(OT)and the information technolog...Time-sensitive networking(TSN)is an important research area for updating the infrastructure of industrial Internet of Things.As a product of the integration of the operation technology(OT)and the information technology(IT),it meets the real-time and deterministic nature of industrial control and is compatible with Ethernet to support the mixed transmission of industrial control data and Ethernet data.This paper systematically summarizes and analyzes the shortcomings of the current mixed transmission technologies of the bursty flows and the periodic flows.To conquer these shortages,we propose a predictive mixed-transmission scheme of the bursty flows and the periodic flows.The core idea is to use the predictability of timetriggered transmission of TSN to further reduce bandwidth loss of the previous mixed-transmission methods.This paper formalizes the probabilistic model of the predictive mixed transmission mechanism and proves that the proposed mecha⁃nism can effectively reduce the loss of bandwidth.Finally,based on the formalized probabilistic model,we simulate the bandwidth loss of the proposed mechanism.The results demonstrate that compared with the previous mixed-transmission method,the bandwidth loss of the pro⁃posed mechanism achieves a 79.48%reduction on average.展开更多
Deterministic transmission plays a vital role in industrial networks.The time-sensitive network(TSN)protocol family offers a promising paradigm for transmitting time-critical data.To achieve low latency and high Quali...Deterministic transmission plays a vital role in industrial networks.The time-sensitive network(TSN)protocol family offers a promising paradigm for transmitting time-critical data.To achieve low latency and high Quality of Service(QoS)in TSN,appropriate data flow scheduling is needed under the given network topology and data flow requirements to fully utilize the potential of TSN.Both time-triggered flows and sporadic flows can carry high-priority data and need to be considered jointly to eliminate the effects of each other.To this end,in this work,we investigate the challenging mixed-flow scheduling problem and propose a novel diffusion-based algorithm,DiffTSN,to solve the joint routing and scheduling problem of mixed flows.We transform the sporadic flows into probabilistic flows and design certain mechanisms to fit the nature of these probabilistic flows.For routing,we transform the problem into a diffusion policy and constraint denoising process with a value guide to achieve a better routing policy.For scheduling,we adopt a first-valid-time-slot algorithm to determine the start transmission time of the flows.We train and evaluate DiffTSN in our TSN simulator.Experiments show that DiffTSN outperforms state-of-the-art algorithms in various metrics.展开更多
Market demand is becoming increasingly time-sensitive in competitive environments.Hence,supply disruptions will have a more serious impact on the profits of supply chains.This study applies a Stackelberg competition b...Market demand is becoming increasingly time-sensitive in competitive environments.Hence,supply disruptions will have a more serious impact on the profits of supply chains.This study applies a Stackelberg competition between a single supplier and a single manufacturer in a time-sensitive supply chain in a cloud manufacturing environment.We aim to address the supplier’s production capacity recovery issues and the manufacturer’s incentive decision issues after supply disruption.We find that the supplier is in a weak position when the information is symmetrical.The manufacturer can encourage the supplier to shorten the recovery time by raising the unit wholesale price.When the supplier’s unit production cost remains unchanged but the unit wholesale price increases,the profit of the supplier first increases and then decreases.In addition,under the centralized decision-making setting,the optimal recovery time of the supplier is shorter and the optimal unit market price of the product is lower than that under decentralized decision-making.We further find that resource sharing can shorten the optimal recovery time,but it does not necessarily play an incentivizing role.展开更多
Objective:To explore the effect of implementing a time-sensitive incentive model combined with specialized rehabilitation nursing in patients with severe pneumonia and respiratory failure.Methods:Seventy-eight patient...Objective:To explore the effect of implementing a time-sensitive incentive model combined with specialized rehabilitation nursing in patients with severe pneumonia and respiratory failure.Methods:Seventy-eight patients with severe pneumonia and respiratory failure admitted from January 2024 to February 2025 were selected and randomly divided into two groups using a computer-based random drawing method.The control group(39 patients)received routine nursing,while the observation group(39 patients)received a time-sensitive incentive model combined with specialized rehabilitation nursing.Lung function and adverse emotional states were compared between the two groups.Results:After 2 weeks of nursing,the lung function of the observation group was higher than that of the control group(P<0.05),and the adverse emotional states of the observation group were lower than those of the control group(P<0.05).Conclusion:Implementing a time-sensitive incentive model combined with specialized rehabilitation nursing in patients with severe pneumonia and respiratory failure can improve lung function and emotional state.展开更多
In deep underground engineering,understanding of time-related stress memory properties is critical to evaluate the in situ stress conditions of a rock mass.In this study,the time-sensitivity mechanism of the rock stre...In deep underground engineering,understanding of time-related stress memory properties is critical to evaluate the in situ stress conditions of a rock mass.In this study,the time-sensitivity mechanism of the rock stress memory properties under tensile stress was investigated.It was found that the material property(Poisson’s ratio)and crack angle were the controlling factors of the Kaiser effect(KE)under tensile stress.In particular,the time-sensitivity of the stress memory properties was closely related to the crack growth path.When the failure of the rock specimen was dominated by tensile microcracks and the crack development direction was deflected by up to 30°in the successive loading process,the stress memory capacity was likely to be time-independent for a sandstone specimen.The distribution of the Felicity ratio in a Brazilian test was more discrete than that in a three-point bending test It also showed that the changes in the crack path,rather than the time interval between successive loading cycles,led to inaccuracy of the detected KE.This study provides insights into stress memory-related issues under uniaxial or more complex stress conditions and thus facilitates development of methods for testing in situ mechanical behaviors of rocks with acoustic emission(AE)technology.展开更多
For permanent faults(PF)in the power communication network(PCN),such as link interruptions,the timesensitive networking(TSN)relied on by PCN,typically employs spatial redundancy fault-tolerance methods to keep service...For permanent faults(PF)in the power communication network(PCN),such as link interruptions,the timesensitive networking(TSN)relied on by PCN,typically employs spatial redundancy fault-tolerance methods to keep service stability and reliability,which often limits TSN scheduling performance in fault-free ideal states.So this paper proposes a graph attention residual network-based routing and fault-tolerant scheduling mechanism(GRFS)for data flow in PCN,which specifically includes a communication system architecture for integrated terminals based on a cyclic queuing and forwarding(CQF)model and fault recovery method,which reduces the impact of faults by simplified scheduling configurations of CQF and fault-tolerance of prioritizing the rerouting of faulty time-sensitive(TS)flows;considering that PF leading to changes in network topology is more appropriately solved by doing routing and time slot injection decisions hop-by-hop,and that reasonable network load can reduce the damage caused by PF and reserve resources for the rerouting of faulty TS flows,an optimization model for joint routing and scheduling is constructed with scheduling success rate as the objective,and with traffic latency and network load as constraints;to catch changes in TSN topology and traffic load,a D3QN algorithm based on a multi-head graph attention residual network(MGAR)is designed to solve the problem model,where the MGAR based encoder reconstructs the TSN status into feature embedding vectors,and a dueling network decoder performs decoding tasks on the reconstructed feature embedding vectors.Simulation results show that GRFS outperforms heuristic fault-tolerance algorithms and other benchmark schemes by approximately 10%in routing and scheduling success rate in ideal states and 5%in rerouting and rescheduling success rate in fault states.展开更多
Game theory can be applied to the air combat decision-making problem of multiple unmanned combat air vehicles(UCAVs).However,it is difficult to have satisfactory decision-making results completely relying on air comba...Game theory can be applied to the air combat decision-making problem of multiple unmanned combat air vehicles(UCAVs).However,it is difficult to have satisfactory decision-making results completely relying on air combat situation information,because there is a lot of time-sensitive information in a complex air combat environment.In this paper,a constraint strategy game approach is developed to generate intelligent decision-making for multiple UCAVs in complex air combat environment with air combat situation information and time-sensitive information.Initially,a constraint strategy game is employed to model attack-defense decision-making problem in complex air combat environment.Then,an algorithm is proposed for solving the constraint strategy game based on linear programming and linear inequality(CSG-LL).Finally,an example is given to illustrate the effectiveness of the proposed approach.展开更多
Attacking time-sensitive targets has rigid demands for the timeliness and reliability of information transmission, while typical Media Access Control（MAC） designed for this application works well only in very light-...Attacking time-sensitive targets has rigid demands for the timeliness and reliability of information transmission, while typical Media Access Control（MAC） designed for this application works well only in very light-load scenarios; as a consequence, the performances of system throughput and channel utilization are degraded. For this problem, a feedback-retransmission based asynchronous FRequency hopping Media Access（FRMA） control protocol is proposed. Burst communication, asynchronous Frequency Hopping（FH）, channel coding, and feedback retransmission are utilized in FRMA. With the mechanism of asynchronous FH, immediate packet transmission and multi-packet reception can be realized, and thus the timeliness is improved.Furthermore, reliability can be achieved via channel coding and feedback retransmission. With theories of queuing theory, Markov model, packets collision model, and discrete Laplace transformation, the formulas of packet success probability, system throughput, average packet end-to-end delay, and delay distribution are obtained. The approximation accuracy of theoretical derivation is verified by experimental results. Within a light-load network, the proposed FRMA has the ability of millisecond delay and 99% reliability as well as outperforms the non-feedback-retransmission based asynchronous frequency hopping media access control protocol.展开更多
With the increasing data volume of train on-board system,real-time performance has become the most critical factor to ensure the safety of train operation.Considering that standard Ethernet cannot meet the real-time r...With the increasing data volume of train on-board system,real-time performance has become the most critical factor to ensure the safety of train operation.Considering that standard Ethernet cannot meet the real-time requirement of existing train communication network(TCN),the time-sensitive network(TSN)technology for TCN is introduced.To solve the time-delay problem,an adaptive switch queue selection mechanism for traffic scheduling is proposed.Firstly,the topology model of TCN based on TSN and the traffic model are described.Then,the K shortest path routing algorithm based on load balancing provides the optimal routing for the scheduling process.Finally,the adaptive switch queue selection mechanism is introduced to solve the aggregation flow conflict problem effectively,queue resources are properly allocated,and the gate control list(GCL)of each frame in the queue is obtained.Experimental results show that compared with the traditional constraint model,the schedulability of the model with an adaptive switch queue selection mechanism increases by 33.0%,and the maximum end-to-end delay and network jitter decrease by 19.1%and 18.6%on average respectively.It can provide theoretical support and application reference for the real-time performance optimization of TCN based on TSN.展开更多
To encourage retailers to submit orders as soon as possible,manufacturers usually launch a time-sensitivity promotional mechanism that the earlier you order,the cheaper the wholesale price will be in advance of the se...To encourage retailers to submit orders as soon as possible,manufacturers usually launch a time-sensitivity promotional mechanism that the earlier you order,the cheaper the wholesale price will be in advance of the selling season.This paper aims to investigate if the mechanism can improve supply chain performance.A dyadic decentralized supply chain system comprising a single manufacturer and a single retailer is viewed as a research framework.Initially,a benchmark model is proposed to provide a criterion-referenced for coordinating the supply chain in a non-standard distribution environment.Second,a time-sensitive wholesale price contract is constructed to confirm that the mechanism can coordinate the supply chain.However,the retailer accepts the entire forecast risk under the contract.An improved contract called a time-sensitive revenue-sharing contract is constructed based on the notion that the manufacturer shares partial forecast risk.The results show that participants can arbitrarily divide the optimal supply chain's expected profit between the constructed price contracts;however,two differences exist between the contracts,that is,participants have contract preferences.Finally,a numerical analysis and a few management insights are given.展开更多
As a result of the growing complexity of industrial Internet applications,traditional hardware-based network designs are encountering challenges in terms of programmability and dynamic adaptability as they struggle to...As a result of the growing complexity of industrial Internet applications,traditional hardware-based network designs are encountering challenges in terms of programmability and dynamic adaptability as they struggle to meet the real-time,high-reliability transmission requirements for the vast quantities of data generated in industrial environments.This paper proposes a holistic software-defined deterministic network(HSDDN)design solution.This solution uses a centralized controller to implement a comprehensive software definition,ranging from the network layer down to the physical layer.Within the wireless access domain,we decouple the standard radio-frequency modules from baseband processing to realize a software-defined physical layer,which then allows us to adjust the data transmission cycles and tag the trigger rates to meet demand for low-power,high-concurrency transmission.Within the wired network domain,we integrate software-defined networking with time-sensitive networking and propose a coordinated design strategy to address routing and the deterministic scheduling problem.We define a set of constraints to ensure collaborative transmission of the periodic and aperiodic data flows.To guarantee load balancing across all paths and timeslots,we introduce the Jain’s fairness index as the optimization objective and then construct a nondeterministic polynomial-time(NP)-hard joint optimization problem.Furthermore,an algorithm called Tabu search for routing and scheduling with dual-stages(TSRS-DS)is proposed.Simulation experiments demonstrate the effectiveness of the proposed HSDDN architecture.展开更多
Hashtags, terms prefixed by a hash-symbol #, are widely used and inserted anywhere within short messages （tweets） on micro-blogging systems as they present rich sen- timent information on topics that people are inte...Hashtags, terms prefixed by a hash-symbol #, are widely used and inserted anywhere within short messages （tweets） on micro-blogging systems as they present rich sen- timent information on topics that people are interested in. In this paper, we focus on the problem of hashtag recommenda- tion considering their personalized and temporal aspects. As far as we know, this is the first work addressing this issue spe- cially to recommend personalized hashtags combining long- term and short-term user interest. We introduce three features to capture personal and temporal user interest： 1） hashtag textual information; 2） user behavior; and 3） time. We of- fer two recommendation models for comparison： a linear- combined model, and an enhanced session-based temporal graph （STG） model, Topic-STG, considering the features to learn user preferences and subsequently recommend person- alized hashtags. Experiments on two real tweet datasets illus- trate the effectiveness of the proposed models and algorithms.展开更多
基金supported in part by National Key R&D Program of China(Grant No.2022YFC3803700)in part by the National Natural Science Foundation of China(Grant No.92067102)in part by the project of Beijing Laboratory of Advanced Information Networks.
文摘The rise of time-sensitive applications with broad geographical scope drives the development of time-sensitive networking(TSN)from intra-domain to inter-domain to ensure overall end-to-end connectivity requirements in heterogeneous deployments.When multiple TSN networks interconnect over non-TSN networks,all devices in the network need to be syn-chronized by sharing a uniform time reference.How-ever,most non-TSN networks are best-effort.Path delay asymmetry and random noise accumulation can introduce unpredictable time errors during end-to-end time synchronization.These factors can degrade syn-chronization performance.Therefore,cross-domain time synchronization becomes a challenging issue for multiple TSN networks interconnected by non-TSN networks.This paper presents a cross-domain time synchronization scheme that follows the software-defined TSN(SD-TSN)paradigm.It utilizes a com-bined control plane constructed by a coordinate con-troller and a domain controller for centralized control and management of cross-domain time synchroniza-tion.The general operation flow of the cross-domain time synchronization process is designed.The mecha-nism of cross-domain time synchronization is revealed by introducing a synchronization model and an error compensation method.A TSN cross-domain proto-type testbed is constructed for verification.Results show that the scheme can achieve end-to-end high-precision time synchronization with accuracy and sta-bility.
基金this project under Geran Putra Inisiatif(GPI)with reference of GP-GPI/2023/976210。
文摘Accurate time synchronization is fundamental to the correct and efficient operation of Wireless Sensor Networks(WSNs),especially in security-critical,time-sensitive applications.However,most existing protocols degrade substantially under malicious interference.We introduce iSTSP,an Intelligent and Secure Time Synchronization Protocol that implements a four-stage defense pipeline to ensure robust,precise synchronization even in hostile environments:(1)trust preprocessing that filters node participation using behavioral trust scoring;(2)anomaly isolation employing a lightweight autoencoder to detect and excise malicious nodes in real time;(3)reliability-weighted consensus that prioritizes high-trust nodes during time aggregation;and(4)convergence-optimized synchronization that dynamically adjusts parameters using theoretical stability bounds.We provide rigorous convergence analysis including a closed-form expression for convergence time,and validate the protocol through both simulations and realworld experiments on a controlled 16-node testbed.Under Sybil attacks with five malicious nodes within this testbed,iSTSP maintains synchronization error increases under 12%and achieves a rapid convergence.Compared to state-ofthe-art protocols like TPSN,SE-FTSP,and MMAR-CTS,iSTSP offers 60%faster detection,broader threat coverage,and more than 7 times lower synchronization error,with a modest 9.3%energy overhead over 8 h.We argue this is an acceptable trade-off for mission-critical deployments requiring guaranteed security.These findings demonstrate iSTSP’s potential as a reliable solution for secure WSN synchronization and motivate future work on large-scale IoT deployments and integration with energy-efficient communication protocols.
基金supported by the Innovation Scientists and Technicians Troop Construction Projects of Henan Province(224000510002)。
文摘Time-Sensitive Network(TSN)with deterministic transmission capability is increasingly used in many emerging fields.It mainly guarantees the Quality of Service(QoS)of applications with strict requirements on time and security.One of the core features of TSN is traffic scheduling with bounded low delay in the network.However,traffic scheduling schemes in TSN are usually synthesized offline and lack dynamism.To implement incremental scheduling of newly arrived traffic in TSN,we propose a Dynamic Response Incremental Scheduling(DR-IS)method for time-sensitive traffic and deploy it on a software-defined time-sensitive network architecture.Under the premise of meeting the traffic scheduling requirements,we adopt two modes,traffic shift and traffic exchange,to dynamically adjust the time slot injection position of the traffic in the original scheme,and determine the sending offset time of the new timesensitive traffic to minimize the global traffic transmission jitter.The evaluation results show that DRIS method can effectively control the large increase of traffic transmission jitter in incremental scheduling without affecting the transmission delay,thus realizing the dynamic incremental scheduling of time-sensitive traffic in TSN.
基金the National Key R&D Program of China(2018YFA0701601 and 2020YFA0711301)the National Natural Science Foundation of China(61771286,61941104,and 61922049)the Tsinghua University-China Mobile Communications Group Co.,Ltd.Joint Institute.
文摘In the upcoming sixth-generation(6G)era,the demand for constructing a wide-area time-sensitive Internet of Things(IoT)continues to increase.As conventional cellular technologies are difficult to directly use for wide-area time-sensitive IoT,it is beneficial to use non-terrestrial infrastructures,including satellites and unmanned aerial vehicles(UAVs).Thus,we can build a non-terrestrial network(NTN)using a cell-free architecture.Driven by the time-sensitive requirements and uneven distribution of IoT devices,the NTN must be empowered using mobile edge computing(MEC)while providing oasisoriented on-demand coverage for devices.Nevertheless,communication and MEC systems are coupled with each other under the influence of a complex propagation environment in the MEC-empowered NTN,which makes it difficult to coordinate the resources.In this study,we propose a process-oriented framework to design communication and MEC systems in a time-division manner.In this framework,large-scale channel state information(CSI)is used to characterize the complex propagation environment at an affordable cost,where a nonconvex latency minimization problem is formulated.Subsequently,the approximated problem is provided,and it can be decomposed into sub-problems.These sub-problems are then solved iteratively.The simulation results demonstrated the superiority of the proposed process-oriented scheme over other algorithms,implied that the payload deployments of UAVs should be appropriately predesigned to improve the efficiency of using resources,and confirmed that it is advantageous to integrate NTN with MEC for wide-area time-sensitive IoT.
基金supported by the National Natural Science Foundation of China (60774064)the Aerospace Science Foundation (05D53022)the Youth for NPU Teachers Scientific and Technological Innovation Foundation (W016210)
文摘To improve the effect of destroying time-sensitive target （TST）, a method of operational effectiveness evaluation is presented and some influential factors are analyzed based on the combat flow of system for destroying TST. Considering the possible operation modes of the system, a waved operation mode and a continuous operation mode are put forward at first. At the same time, some relative formulas are modified. In examples, the influential factors and operation modes are analyzed based on the system effectiveness. From simulation results, some design and operation strategies of the system for destroying time sensitive targets are concluded, which benefit to the improvement of the system effectiveness.
基金sponsored in part by the National Key Research and Development Project under Grants Nos. 2018YFB1308601 and 2017YFE0119300the National Natural Science Foundation of China under Grant No. 62002013+1 种基金the Project funded by China Postdoctoral Science Foundation Grants Nos. 2019M660439 and 2020T130049the Industry-University-Research Cooperation Fund of ZTE Corporation.
文摘Time-sensitive networking(TSN)is an important research area for updating the infrastructure of industrial Internet of Things.As a product of the integration of the operation technology(OT)and the information technology(IT),it meets the real-time and deterministic nature of industrial control and is compatible with Ethernet to support the mixed transmission of industrial control data and Ethernet data.This paper systematically summarizes and analyzes the shortcomings of the current mixed transmission technologies of the bursty flows and the periodic flows.To conquer these shortages,we propose a predictive mixed-transmission scheme of the bursty flows and the periodic flows.The core idea is to use the predictability of timetriggered transmission of TSN to further reduce bandwidth loss of the previous mixed-transmission methods.This paper formalizes the probabilistic model of the predictive mixed transmission mechanism and proves that the proposed mecha⁃nism can effectively reduce the loss of bandwidth.Finally,based on the formalized probabilistic model,we simulate the bandwidth loss of the proposed mechanism.The results demonstrate that compared with the previous mixed-transmission method,the bandwidth loss of the pro⁃posed mechanism achieves a 79.48%reduction on average.
基金supported by the Guangdong Science and Technology Program under Grant Nos.2024B0101040007 and 2024B0101020004the Guangdong Basic and Applied Basic Research Foundation under Grant No.2023B1515120058+5 种基金the National Science Foundation of China under Grant No.62172455the Guangdong Science and Technology Department Pearl River Talent Program under Grant No.2019QN01X140the Guangzhou Basic and Applied Basic Research Program under Grant No.2024A04J6367the Fundamental Research Funds for the Central Universities of China under Grant No.24qnpy138the Program for Guangdong Introducing Innovative and Entrepreneurial Teams under Grant No.2017ZT07X355the Department of Science and Technology of Guangdong Province of China under Grant No.2022A0505050028.
文摘Deterministic transmission plays a vital role in industrial networks.The time-sensitive network(TSN)protocol family offers a promising paradigm for transmitting time-critical data.To achieve low latency and high Quality of Service(QoS)in TSN,appropriate data flow scheduling is needed under the given network topology and data flow requirements to fully utilize the potential of TSN.Both time-triggered flows and sporadic flows can carry high-priority data and need to be considered jointly to eliminate the effects of each other.To this end,in this work,we investigate the challenging mixed-flow scheduling problem and propose a novel diffusion-based algorithm,DiffTSN,to solve the joint routing and scheduling problem of mixed flows.We transform the sporadic flows into probabilistic flows and design certain mechanisms to fit the nature of these probabilistic flows.For routing,we transform the problem into a diffusion policy and constraint denoising process with a value guide to achieve a better routing policy.For scheduling,we adopt a first-valid-time-slot algorithm to determine the start transmission time of the flows.We train and evaluate DiffTSN in our TSN simulator.Experiments show that DiffTSN outperforms state-of-the-art algorithms in various metrics.
基金supported by the National Social Science Fund of China under Grant number 17BGL084
文摘Market demand is becoming increasingly time-sensitive in competitive environments.Hence,supply disruptions will have a more serious impact on the profits of supply chains.This study applies a Stackelberg competition between a single supplier and a single manufacturer in a time-sensitive supply chain in a cloud manufacturing environment.We aim to address the supplier’s production capacity recovery issues and the manufacturer’s incentive decision issues after supply disruption.We find that the supplier is in a weak position when the information is symmetrical.The manufacturer can encourage the supplier to shorten the recovery time by raising the unit wholesale price.When the supplier’s unit production cost remains unchanged but the unit wholesale price increases,the profit of the supplier first increases and then decreases.In addition,under the centralized decision-making setting,the optimal recovery time of the supplier is shorter and the optimal unit market price of the product is lower than that under decentralized decision-making.We further find that resource sharing can shorten the optimal recovery time,but it does not necessarily play an incentivizing role.
文摘Objective:To explore the effect of implementing a time-sensitive incentive model combined with specialized rehabilitation nursing in patients with severe pneumonia and respiratory failure.Methods:Seventy-eight patients with severe pneumonia and respiratory failure admitted from January 2024 to February 2025 were selected and randomly divided into two groups using a computer-based random drawing method.The control group(39 patients)received routine nursing,while the observation group(39 patients)received a time-sensitive incentive model combined with specialized rehabilitation nursing.Lung function and adverse emotional states were compared between the two groups.Results:After 2 weeks of nursing,the lung function of the observation group was higher than that of the control group(P<0.05),and the adverse emotional states of the observation group were lower than those of the control group(P<0.05).Conclusion:Implementing a time-sensitive incentive model combined with specialized rehabilitation nursing in patients with severe pneumonia and respiratory failure can improve lung function and emotional state.
基金funded by the National Natural Science Foundation of China(Grant No.51779021)Chongqing Natural Science Foundation(Grant No.cstc2019jcyj-msxm2176)Scientific and Technological Research Program of Chongqing Municipal Education Commission(Grant No.KJQN201800745).
文摘In deep underground engineering,understanding of time-related stress memory properties is critical to evaluate the in situ stress conditions of a rock mass.In this study,the time-sensitivity mechanism of the rock stress memory properties under tensile stress was investigated.It was found that the material property(Poisson’s ratio)and crack angle were the controlling factors of the Kaiser effect(KE)under tensile stress.In particular,the time-sensitivity of the stress memory properties was closely related to the crack growth path.When the failure of the rock specimen was dominated by tensile microcracks and the crack development direction was deflected by up to 30°in the successive loading process,the stress memory capacity was likely to be time-independent for a sandstone specimen.The distribution of the Felicity ratio in a Brazilian test was more discrete than that in a three-point bending test It also showed that the changes in the crack path,rather than the time interval between successive loading cycles,led to inaccuracy of the detected KE.This study provides insights into stress memory-related issues under uniaxial or more complex stress conditions and thus facilitates development of methods for testing in situ mechanical behaviors of rocks with acoustic emission(AE)technology.
基金supported by Research and Application of Edge IoT Technology for Distributed New Energy Consumption in Distribution Areas,Project Number(5108-202218280A-2-394-XG)。
文摘For permanent faults(PF)in the power communication network(PCN),such as link interruptions,the timesensitive networking(TSN)relied on by PCN,typically employs spatial redundancy fault-tolerance methods to keep service stability and reliability,which often limits TSN scheduling performance in fault-free ideal states.So this paper proposes a graph attention residual network-based routing and fault-tolerant scheduling mechanism(GRFS)for data flow in PCN,which specifically includes a communication system architecture for integrated terminals based on a cyclic queuing and forwarding(CQF)model and fault recovery method,which reduces the impact of faults by simplified scheduling configurations of CQF and fault-tolerance of prioritizing the rerouting of faulty time-sensitive(TS)flows;considering that PF leading to changes in network topology is more appropriately solved by doing routing and time slot injection decisions hop-by-hop,and that reasonable network load can reduce the damage caused by PF and reserve resources for the rerouting of faulty TS flows,an optimization model for joint routing and scheduling is constructed with scheduling success rate as the objective,and with traffic latency and network load as constraints;to catch changes in TSN topology and traffic load,a D3QN algorithm based on a multi-head graph attention residual network(MGAR)is designed to solve the problem model,where the MGAR based encoder reconstructs the TSN status into feature embedding vectors,and a dueling network decoder performs decoding tasks on the reconstructed feature embedding vectors.Simulation results show that GRFS outperforms heuristic fault-tolerance algorithms and other benchmark schemes by approximately 10%in routing and scheduling success rate in ideal states and 5%in rerouting and rescheduling success rate in fault states.
基金supported by Major Projects for Science and Technology Innovation 2030(Grant No.2018AA0100800)Equipment Pre-research Foundation of Laboratory(Grant No.61425040104)in part by Jiangsu Province“333”project under Grant BRA2019051.
文摘Game theory can be applied to the air combat decision-making problem of multiple unmanned combat air vehicles(UCAVs).However,it is difficult to have satisfactory decision-making results completely relying on air combat situation information,because there is a lot of time-sensitive information in a complex air combat environment.In this paper,a constraint strategy game approach is developed to generate intelligent decision-making for multiple UCAVs in complex air combat environment with air combat situation information and time-sensitive information.Initially,a constraint strategy game is employed to model attack-defense decision-making problem in complex air combat environment.Then,an algorithm is proposed for solving the constraint strategy game based on linear programming and linear inequality(CSG-LL).Finally,an example is given to illustrate the effectiveness of the proposed approach.
基金supported by the National Natural Science Foundation of China(No.61501496)
文摘Attacking time-sensitive targets has rigid demands for the timeliness and reliability of information transmission, while typical Media Access Control（MAC） designed for this application works well only in very light-load scenarios; as a consequence, the performances of system throughput and channel utilization are degraded. For this problem, a feedback-retransmission based asynchronous FRequency hopping Media Access（FRMA） control protocol is proposed. Burst communication, asynchronous Frequency Hopping（FH）, channel coding, and feedback retransmission are utilized in FRMA. With the mechanism of asynchronous FH, immediate packet transmission and multi-packet reception can be realized, and thus the timeliness is improved.Furthermore, reliability can be achieved via channel coding and feedback retransmission. With theories of queuing theory, Markov model, packets collision model, and discrete Laplace transformation, the formulas of packet success probability, system throughput, average packet end-to-end delay, and delay distribution are obtained. The approximation accuracy of theoretical derivation is verified by experimental results. Within a light-load network, the proposed FRMA has the ability of millisecond delay and 99% reliability as well as outperforms the non-feedback-retransmission based asynchronous frequency hopping media access control protocol.
基金supported by the National Natural Science Foundation of China(52072081)Major Project of Science and Technology of Guangxi Province of China(Guike AB23075209)+2 种基金Guangxi Manufacturing Systems and Advanced Manufacturing Technology Key Laboratory Director Fund(24050-44-S015)Innovation Project of Guangxi Graduate Education(YCSW2024135)Major Talent Project in Guangxi Zhuang Autonomous Region。
文摘With the increasing data volume of train on-board system,real-time performance has become the most critical factor to ensure the safety of train operation.Considering that standard Ethernet cannot meet the real-time requirement of existing train communication network(TCN),the time-sensitive network(TSN)technology for TCN is introduced.To solve the time-delay problem,an adaptive switch queue selection mechanism for traffic scheduling is proposed.Firstly,the topology model of TCN based on TSN and the traffic model are described.Then,the K shortest path routing algorithm based on load balancing provides the optimal routing for the scheduling process.Finally,the adaptive switch queue selection mechanism is introduced to solve the aggregation flow conflict problem effectively,queue resources are properly allocated,and the gate control list(GCL)of each frame in the queue is obtained.Experimental results show that compared with the traditional constraint model,the schedulability of the model with an adaptive switch queue selection mechanism increases by 33.0%,and the maximum end-to-end delay and network jitter decrease by 19.1%and 18.6%on average respectively.It can provide theoretical support and application reference for the real-time performance optimization of TCN based on TSN.
基金Research Project of Humanities and Social Science of Ministry of Education(Grant No.18YJC630030)The Key Projects of The National Social Science Foundation(Grant No.17AGL007)+1 种基金Project of Chongqing Science and Technology Bureau(Grant cstc2018jsyj-jsyjX0014)Chongqing Engineering Research Center for Processing,Storage and Transportation of Characterized Agro-Products(Grant KFJJ2016026).
文摘To encourage retailers to submit orders as soon as possible,manufacturers usually launch a time-sensitivity promotional mechanism that the earlier you order,the cheaper the wholesale price will be in advance of the selling season.This paper aims to investigate if the mechanism can improve supply chain performance.A dyadic decentralized supply chain system comprising a single manufacturer and a single retailer is viewed as a research framework.Initially,a benchmark model is proposed to provide a criterion-referenced for coordinating the supply chain in a non-standard distribution environment.Second,a time-sensitive wholesale price contract is constructed to confirm that the mechanism can coordinate the supply chain.However,the retailer accepts the entire forecast risk under the contract.An improved contract called a time-sensitive revenue-sharing contract is constructed based on the notion that the manufacturer shares partial forecast risk.The results show that participants can arbitrarily divide the optimal supply chain's expected profit between the constructed price contracts;however,two differences exist between the contracts,that is,participants have contract preferences.Finally,a numerical analysis and a few management insights are given.
基金This work was supported by the National Natural Science Foundation of China(92167205,92167205 and 62025305).
文摘As a result of the growing complexity of industrial Internet applications,traditional hardware-based network designs are encountering challenges in terms of programmability and dynamic adaptability as they struggle to meet the real-time,high-reliability transmission requirements for the vast quantities of data generated in industrial environments.This paper proposes a holistic software-defined deterministic network(HSDDN)design solution.This solution uses a centralized controller to implement a comprehensive software definition,ranging from the network layer down to the physical layer.Within the wireless access domain,we decouple the standard radio-frequency modules from baseband processing to realize a software-defined physical layer,which then allows us to adjust the data transmission cycles and tag the trigger rates to meet demand for low-power,high-concurrency transmission.Within the wired network domain,we integrate software-defined networking with time-sensitive networking and propose a coordinated design strategy to address routing and the deterministic scheduling problem.We define a set of constraints to ensure collaborative transmission of the periodic and aperiodic data flows.To guarantee load balancing across all paths and timeslots,we introduce the Jain’s fairness index as the optimization objective and then construct a nondeterministic polynomial-time(NP)-hard joint optimization problem.Furthermore,an algorithm called Tabu search for routing and scheduling with dual-stages(TSRS-DS)is proposed.Simulation experiments demonstrate the effectiveness of the proposed HSDDN architecture.
文摘Hashtags, terms prefixed by a hash-symbol #, are widely used and inserted anywhere within short messages （tweets） on micro-blogging systems as they present rich sen- timent information on topics that people are interested in. In this paper, we focus on the problem of hashtag recommenda- tion considering their personalized and temporal aspects. As far as we know, this is the first work addressing this issue spe- cially to recommend personalized hashtags combining long- term and short-term user interest. We introduce three features to capture personal and temporal user interest： 1） hashtag textual information; 2） user behavior; and 3） time. We of- fer two recommendation models for comparison： a linear- combined model, and an enhanced session-based temporal graph （STG） model, Topic-STG, considering the features to learn user preferences and subsequently recommend person- alized hashtags. Experiments on two real tweet datasets illus- trate the effectiveness of the proposed models and algorithms.
