Improving the cooperative scheduling efficiency of equipment is the key for automated container terminals to copewith the development trend of large-scale ships. In order to improve the solution efficiency of the exis...Improving the cooperative scheduling efficiency of equipment is the key for automated container terminals to copewith the development trend of large-scale ships. In order to improve the solution efficiency of the existing spacetimenetwork (STN) model for the cooperative scheduling problem of yard cranes (YCs) and automated guidedvehicles (AGVs) and extend its application scenarios, two improved STN models are proposed. The flow balanceconstraints in the original model are decomposed, and the trajectory constraints of YCs and AGVs are added toacquire the model STN_A. The coupling constraint in STN_A is updated, and buffer constraints are added toSTN_A so that themodel STN_B is built.As the size of the problem increases, the solution speed of CPLEX becomesthe bottleneck. So a heuristic method containing three groups of heuristic rules is designed to obtain a near-optimalsolution quickly. Experimental results showthat the computation time of STN_A is shortened by 49.47% on averageand the gap is reduced by 1.69% on average compared with the original model. The gap between the solution ofthe heuristic rules and the solution of CPLEX is less than 3.50%, and the solution time of the heuristic rules is onaverage 99.85% less than the solution time of CPLEX. Compared with STN_A, the computation time for solvingSTN_B increases by 58.93% on average.展开更多
The containerized traffic has come into being for over forty years and has become the most important mode of sea transportation. Although containerized traffic trade has been developed in port cities of Dalian, Yingko...The containerized traffic has come into being for over forty years and has become the most important mode of sea transportation. Although containerized traffic trade has been developed in port cities of Dalian, Yingkou, Dandong and Jinzhou in Liaoning Province, yet their development sped are obviously slower than the entire national development pace. In the article, the authors make a systematic study on the current situation and the potential developmental possibility of containerized traffic in Liaoning Province. It is held that the relative low proportion of the supply of goods in hinterland is relative low which will restrict directly the development potentiality of the container harbors in Liaoning. Three countermeasures of the containerized traffic development were given accordingly.展开更多
The study was conducted to evaluate the field performance of local plantain genotypes;Apem, Oniaba, Apantu (AAB) and FHIA 21 (AAAB) suckers that were raised in containers (polybags) and their corresponding conventiona...The study was conducted to evaluate the field performance of local plantain genotypes;Apem, Oniaba, Apantu (AAB) and FHIA 21 (AAAB) suckers that were raised in containers (polybags) and their corresponding conventional suckers. Half of the containerized and conventional suckers in each plot were mulched with empty fruit bunch (EFB). Survival rate three months after transplanting was higher in containerized (100%) than conventional materials (60%) with or without mulching. Mulching increased the girth at flowering and total leaf area by 8% and 28% respectively, and reduced the number of days to flowering. Mulching also increased yield of plantain and the highest was recorded in FHIA 21. Bunch yield of container raised suckers per hectare was 19% greater than conventional suckers, due to higher survival rate after transplanting. Bunch yield among the genotypes in decreasing order was as follows, FHIA21 (20.7), Oniaba (16.9), Apem (15.9) and Apantu (13.2) tons/ha. Mulching increased the yield components such as, pulp weight, peel weight, finger weight and number of fingers. Genotypic variation in pulp yield was in the following decreasing order Apantu > FHIA 21 > Oniaba > Apem fresh weight. The pulp to peel ratio was in the following decreasing order Apantu > FHIA 21 > Apem > Oniaba. It is concluded that raising plantain suckers in polybags and applying EFB mulch is an improved production technique.展开更多
Internet of Vehicles(IoV)applications integrating with edge com-puting will significantly drive the growth of IoV.However,the contradiction between the high-speed mobility of vehicles,the delay sensitivity of corre-sp...Internet of Vehicles(IoV)applications integrating with edge com-puting will significantly drive the growth of IoV.However,the contradiction between the high-speed mobility of vehicles,the delay sensitivity of corre-sponding IoV applications and the limited coverage and resource capacity of distributed edge servers will pose challenges to the service continuity and stability of IoV applications.IoV application migration is a promising solution that can be supported by application containerization,a technology for seamless cross-edge-server application migration without user perception.Therefore,this paper proposes the container-based IoV edge application migration mechanism,consisting of three parts.The first is the migration trigger determination algorithm for cross-border migration and service degra-dation migration,respectively,based on trajectory prediction and traffic awareness to improve the determination accuracy.The second is the migration target decision calculation model for minimizing the average migration time and maximizing the average service time to reduce migration times and improve the stability and adaptability of migration decisions.The third is the migration decision algorithm based on the improved artificial bee colony algorithm to avoid local optimal migration decisions.Simulation results show that the proposed migration mechanism can reduce migration times,reduce average migration time,improve average service time and enhance the stability and adaptability of IoV application services.展开更多
A nonlinear semi-analytical scheme is proposed for investigating the finiteamplitude nonlinear sloshing in a horizontally baffled rectangular liquid container under the seismic excitation.The sub-domain method is deve...A nonlinear semi-analytical scheme is proposed for investigating the finiteamplitude nonlinear sloshing in a horizontally baffled rectangular liquid container under the seismic excitation.The sub-domain method is developed to analytically derive the modal behaviors of the baffled linear sloshing.The viscosity dissipation effects from the interior liquid and boundary layers are considered.With the introduction of the generalized time-dependent coordinates,the surface wave elevation and velocity potential are represented by a series of linear modal eigenfunctions.The infinite-dimensional modal system of the nonlinear sloshing is formulated based on the Bateman-Luke variational principle,which is further reduced to the finite-dimensional modal system by using the NarimanovMoiseev asymptotic ordering.The base force and overturning moment induced by the nonlinear sloshing are derived as the functions of the generalized time-dependent coordinates.The present results match well with the available analytical,numerical,and experimental results.The paper examines the surface wave elevation,base force,and overturning moment versus the baffle parameters and excitation amplitude in detail.展开更多
Kubernetes is an open-source container management tool which automates container deployment,container load balancing and container(de)scaling,including Horizontal Pod Autoscaler(HPA),Vertical Pod Autoscaler(VPA).HPA e...Kubernetes is an open-source container management tool which automates container deployment,container load balancing and container(de)scaling,including Horizontal Pod Autoscaler(HPA),Vertical Pod Autoscaler(VPA).HPA enables flawless operation,interactively scaling the number of resource units,or pods,without downtime.Default Resource Metrics,such as CPU and memory use of host machines and pods,are monitored by Kubernetes.Cloud Computing has emerged as a platform for individuals beside the corporate sector.It provides cost-effective infrastructure,platform and software services in a shared environment.On the other hand,the emergence of industry 4.0 brought new challenges for the adaptability and infusion of cloud computing.As the global work environment is adapting constituents of industry 4.0 in terms of robotics,artificial intelligence and IoT devices,it is becoming eminent that one emerging challenge is collaborative schematics.Provision of such autonomous mechanism that can develop,manage and operationalize digital resources like CoBots to perform tasks in a distributed and collaborative cloud environment for optimized utilization of resources,ensuring schedule completion.Collaborative schematics are also linked with Bigdata management produced by large scale industry 4.0 setups.Different use cases and simulation results showed a significant improvement in Pod CPU utilization,latency,and throughput over Kubernetes environment.展开更多
Containerization is a fundamental component of modern cloud-native infrastructure,and Kubernetes is a prominent platform of container orchestration systems.However,containerization raises significant security concerns...Containerization is a fundamental component of modern cloud-native infrastructure,and Kubernetes is a prominent platform of container orchestration systems.However,containerization raises significant security concerns due to the nature of sharing a kernel among multiple containers,which can lead to container breakout or privilege escalation.Kubernetes cannot avoid it as well.While various tools,such as container image scanning and configuration checking,can mitigate container workload vulnerabilities,these are not foolproof and cannot guarantee perfect isolation or prevent every active threat in runtime.As such,a policy enforcement solution is required to tackle the problem,and existing solutions based on LSM(Linux Security Module)frameworks may not be adequate for some situations.To address this,we propose an enforcement system based on BPF-LSM,which leverages eBPF(extended Berkeley Packet Filter)technology to provide fine-grained control and dynamic adoption of security policies.In this paper,we compare different LSM implementations to highlight the challenges of current enforcement solutions before detailing the design of our eBPF-based Kubernetes Runtime Instrumentation and Enforcement System(KRSIE).Finally,we evaluate the effectiveness of our system using a real-world scenario,as measuring the performance of a policy enforcement system is a complex task.Our results show that KRSIE can successfully control containers’behaviors using LSM hooks at container runtime,offering improved container security for cloud-native infrastructure.展开更多
In a cloud-native era,the Kubernetes-based workflow engine enables workflow containerized execution through the inherent abilities of Kubernetes.However,when encountering continuous workflow requests and unexpected re...In a cloud-native era,the Kubernetes-based workflow engine enables workflow containerized execution through the inherent abilities of Kubernetes.However,when encountering continuous workflow requests and unexpected resource request spikes,the engine is limited to the current workflow load information for resource allocation,which lacks the agility and predictability of resource allocation,resulting in over and underprovisioning resources.This mechanism seriously hinders workflow execution efficiency and leads to high resource waste.To overcome these drawbacks,we propose an adaptive resource allocation scheme named adaptive resource allocation scheme(ARAS)for the Kubernetes-based workflow engines.Considering potential future workflow task requests within the current task pod’s lifecycle,the ARAS uses a resource scaling strategy to allocate resources in response to high-concurrency workflow scenarios.The ARAS offers resource discovery,resource evaluation,and allocation functionalities and serves as a key component for our tailored workflow engine(KubeAdaptor).By integrating the ARAS into KubeAdaptor for workflow containerized execution,we demonstrate the practical abilities of KubeAdaptor and the advantages of our ARAS.Compared with the baseline algorithm,experimental evaluation under three distinct workflow arrival patterns shows that ARAS gains time-saving of 9.8% to 40.92% in the average total duration of all workflows,time-saving of 26.4% to 79.86% in the average duration of individual workflow,and an increase of 1% to 16% in centrol processing unit(CPU)and memory resource usage rate.展开更多
Nomadic Vehicular Cloud(NVC)is envisaged in this work.The predo-minant aspects of NVC is,it moves along with the vehicle that initiates it and functions only with the resources of moving vehicles on the heavy traffic ...Nomadic Vehicular Cloud(NVC)is envisaged in this work.The predo-minant aspects of NVC is,it moves along with the vehicle that initiates it and functions only with the resources of moving vehicles on the heavy traffic road without relying on any of the static infrastructure and NVC decides the initiation time of container migration using cell transmission model(CTM).Containers are used in the place of Virtual Machines(VM),as containers’features are very apt to NVC’s dynamic environment.The specifications of 5G NR V2X PC5 interface are applied to NVC,for the feature of not relying on the network coverage.Nowa-days,the peak traffic on the road and the bottlenecks due to it are inevitable,which are seen here as the benefits for VC in terms of resource availability and residual in-network time.The speed range of high-end vehicles poses the issue of dis-connectivity among VC participants,that results the container migration failure.As the entire VC participants are on the move,to maintain proximity of the containers hosted by them,estimating their movements plays a vital role.To infer the vehicle movements on the road stretch and initiate the container migration prior enough to avoid the migration failure due to vehicles dynamicity,this paper proposes to apply the CTM to the container based and 5G NR V2X enabled NVC.The simulation results show that there is a significant increase in the success rate of vehicular cloud in terms of successful container migrations.展开更多
Based on the principle of asexual reproduction,a kind of scale breeding and reproduction technique of Ficus tikoua Bur.container seedlings was explored by using the characteristics of strong adaptability to the enviro...Based on the principle of asexual reproduction,a kind of scale breeding and reproduction technique of Ficus tikoua Bur.container seedlings was explored by using the characteristics of strong adaptability to the environment and fast growth and reproduction.Using non-woven bag as a breeding container for seedlings,the scale breeding and reproduction technique of F.tikoua container seedlings was summarized through the important links of seedling bed construction,seedling collection,soil configuration,container selection,cutting cultivation,field management,and disease and pest control.This technique can achieve differential,massive and sustainable efficient breeding and reproduction of F.tikoua seedlings in a short time.展开更多
【应用背景】快速射电暴(Fast Radio Burst,FRB)搜寻是500米口径球面射电望远镜(FAST)的重要科学目标之一,其计算复杂度高,数据量大,当前算法GPU利用率偏低,数据处理需较多的人工介入操作。【目的】在不修改算法实现的前提下,实现进程级...【应用背景】快速射电暴(Fast Radio Burst,FRB)搜寻是500米口径球面射电望远镜(FAST)的重要科学目标之一,其计算复杂度高,数据量大,当前算法GPU利用率偏低,数据处理需较多的人工介入操作。【目的】在不修改算法实现的前提下,实现进程级GPU并行优化,提高GPU整体资源利用率,简化算法运行调度,支持利用自动化脚本驱动计算过程。【方法】利用容器化封装FRB搜寻算法,结合GPU聚合技术实现多个FRB搜寻计算容器的多进程并行,支持GPU闲时复用。通过容器化封装屏蔽了GPU调用、依赖库管理等技术细节,减少人工介入操作。【结果】算法实验结果表明,在不修改原始算法、不增加GPU资源的前提下,将单GPU绑定6个计算进程,并行优化可实现FRB搜寻算法的加速比达到5.3,并行效率达到0.88,取得良好的并行效果。【结论】基于容器化封装及进程级GPU聚合的并行优化,可实现GPU利用率及计算效率的提升,有效支持自动化处理。该方法还具有良好的通用性,可适用于类似应用的并行优化。展开更多
An innovative multi-layer composite explosion containment vessel(CECV)utilizing a sliding steel platealuminum honeycomb-fiber cloth sandwich is put forward to improve the anti-explosion capacity of a conventional sing...An innovative multi-layer composite explosion containment vessel(CECV)utilizing a sliding steel platealuminum honeycomb-fiber cloth sandwich is put forward to improve the anti-explosion capacity of a conventional single-layer explosion containment vessel(SECV).Firstly,a series of experiments and finite element(FE)simulations of internal explosions are implemented to understand the basic anti-explosion characteristics of a SECV and the rationality of the computational models and methods is verified by the comparison between the experimental results and simulation results.Based on this,the CECV is designed in detail and a variety of FE simulations are carried out to investigate effects of the sandwich structure,the explosive quantity and the laying mode of the fiber cloth on anti-explosion performance and dynamic response of the CECV under internal explosions.Simulation results indicate that the end cover is the critical position for both the SECV and CECV.The maximum pressure of the explosion shock wave and the maximum strain of the CECV can be extremely declined compared to those of the SECV.As a result,the explosive quantity the CECV can sustain is up to 20 times of that the SECV can sustain.Besides,as the explosive quantity increases,the internal pressure of the CECV keeps growing and the plastic deformation and failure of the sandwich structure become more and more severe,yielding plastic strain of the CECV in addition to elastic strain.The results also reveal that the laying angles of the fiber cloth's five layers have an impact on the anti-explosion performance of the CECV.For example,the CECV with fiber cloth layered in 0°/45°/90°/45°/0°mode has the optimal anti-capacity,compared to 0°/0°/0°/0°/0°and 0°/30°/60°/30°/0°modes.Overall,owing to remarkable anti-explosion capacity,this CECV can be regarded as a promising candidate for explosion resistance.展开更多
基金National Natural Science Foundation of China(62073212).
文摘Improving the cooperative scheduling efficiency of equipment is the key for automated container terminals to copewith the development trend of large-scale ships. In order to improve the solution efficiency of the existing spacetimenetwork (STN) model for the cooperative scheduling problem of yard cranes (YCs) and automated guidedvehicles (AGVs) and extend its application scenarios, two improved STN models are proposed. The flow balanceconstraints in the original model are decomposed, and the trajectory constraints of YCs and AGVs are added toacquire the model STN_A. The coupling constraint in STN_A is updated, and buffer constraints are added toSTN_A so that themodel STN_B is built.As the size of the problem increases, the solution speed of CPLEX becomesthe bottleneck. So a heuristic method containing three groups of heuristic rules is designed to obtain a near-optimalsolution quickly. Experimental results showthat the computation time of STN_A is shortened by 49.47% on averageand the gap is reduced by 1.69% on average compared with the original model. The gap between the solution ofthe heuristic rules and the solution of CPLEX is less than 3.50%, and the solution time of the heuristic rules is onaverage 99.85% less than the solution time of CPLEX. Compared with STN_A, the computation time for solvingSTN_B increases by 58.93% on average.
文摘The containerized traffic has come into being for over forty years and has become the most important mode of sea transportation. Although containerized traffic trade has been developed in port cities of Dalian, Yingkou, Dandong and Jinzhou in Liaoning Province, yet their development sped are obviously slower than the entire national development pace. In the article, the authors make a systematic study on the current situation and the potential developmental possibility of containerized traffic in Liaoning Province. It is held that the relative low proportion of the supply of goods in hinterland is relative low which will restrict directly the development potentiality of the container harbors in Liaoning. Three countermeasures of the containerized traffic development were given accordingly.
文摘The study was conducted to evaluate the field performance of local plantain genotypes;Apem, Oniaba, Apantu (AAB) and FHIA 21 (AAAB) suckers that were raised in containers (polybags) and their corresponding conventional suckers. Half of the containerized and conventional suckers in each plot were mulched with empty fruit bunch (EFB). Survival rate three months after transplanting was higher in containerized (100%) than conventional materials (60%) with or without mulching. Mulching increased the girth at flowering and total leaf area by 8% and 28% respectively, and reduced the number of days to flowering. Mulching also increased yield of plantain and the highest was recorded in FHIA 21. Bunch yield of container raised suckers per hectare was 19% greater than conventional suckers, due to higher survival rate after transplanting. Bunch yield among the genotypes in decreasing order was as follows, FHIA21 (20.7), Oniaba (16.9), Apem (15.9) and Apantu (13.2) tons/ha. Mulching increased the yield components such as, pulp weight, peel weight, finger weight and number of fingers. Genotypic variation in pulp yield was in the following decreasing order Apantu > FHIA 21 > Oniaba > Apem fresh weight. The pulp to peel ratio was in the following decreasing order Apantu > FHIA 21 > Apem > Oniaba. It is concluded that raising plantain suckers in polybags and applying EFB mulch is an improved production technique.
基金supported in part by the National Natural Science Foundation of China under Grant 62071070.
文摘Internet of Vehicles(IoV)applications integrating with edge com-puting will significantly drive the growth of IoV.However,the contradiction between the high-speed mobility of vehicles,the delay sensitivity of corre-sponding IoV applications and the limited coverage and resource capacity of distributed edge servers will pose challenges to the service continuity and stability of IoV applications.IoV application migration is a promising solution that can be supported by application containerization,a technology for seamless cross-edge-server application migration without user perception.Therefore,this paper proposes the container-based IoV edge application migration mechanism,consisting of three parts.The first is the migration trigger determination algorithm for cross-border migration and service degra-dation migration,respectively,based on trajectory prediction and traffic awareness to improve the determination accuracy.The second is the migration target decision calculation model for minimizing the average migration time and maximizing the average service time to reduce migration times and improve the stability and adaptability of migration decisions.The third is the migration decision algorithm based on the improved artificial bee colony algorithm to avoid local optimal migration decisions.Simulation results show that the proposed migration mechanism can reduce migration times,reduce average migration time,improve average service time and enhance the stability and adaptability of IoV application services.
基金Project supported by the National Natural Science Foundation of China(Nos.51978336 and11702117)。
文摘A nonlinear semi-analytical scheme is proposed for investigating the finiteamplitude nonlinear sloshing in a horizontally baffled rectangular liquid container under the seismic excitation.The sub-domain method is developed to analytically derive the modal behaviors of the baffled linear sloshing.The viscosity dissipation effects from the interior liquid and boundary layers are considered.With the introduction of the generalized time-dependent coordinates,the surface wave elevation and velocity potential are represented by a series of linear modal eigenfunctions.The infinite-dimensional modal system of the nonlinear sloshing is formulated based on the Bateman-Luke variational principle,which is further reduced to the finite-dimensional modal system by using the NarimanovMoiseev asymptotic ordering.The base force and overturning moment induced by the nonlinear sloshing are derived as the functions of the generalized time-dependent coordinates.The present results match well with the available analytical,numerical,and experimental results.The paper examines the surface wave elevation,base force,and overturning moment versus the baffle parameters and excitation amplitude in detail.
文摘Kubernetes is an open-source container management tool which automates container deployment,container load balancing and container(de)scaling,including Horizontal Pod Autoscaler(HPA),Vertical Pod Autoscaler(VPA).HPA enables flawless operation,interactively scaling the number of resource units,or pods,without downtime.Default Resource Metrics,such as CPU and memory use of host machines and pods,are monitored by Kubernetes.Cloud Computing has emerged as a platform for individuals beside the corporate sector.It provides cost-effective infrastructure,platform and software services in a shared environment.On the other hand,the emergence of industry 4.0 brought new challenges for the adaptability and infusion of cloud computing.As the global work environment is adapting constituents of industry 4.0 in terms of robotics,artificial intelligence and IoT devices,it is becoming eminent that one emerging challenge is collaborative schematics.Provision of such autonomous mechanism that can develop,manage and operationalize digital resources like CoBots to perform tasks in a distributed and collaborative cloud environment for optimized utilization of resources,ensuring schedule completion.Collaborative schematics are also linked with Bigdata management produced by large scale industry 4.0 setups.Different use cases and simulation results showed a significant improvement in Pod CPU utilization,latency,and throughput over Kubernetes environment.
基金supported by the Institute of Information&Communications Technology Planning&Evaluation (IITP)grant funded by the Korea Government (MSIT), (No.2020-0-00952,Development of 5G edge security technology for ensuring 5G+service stability and availability,50%)the Institute of Information and Communications Technology Planning and Evaluation (IITP)grant funded by the MSIT (Ministry of Science and ICT),Korea (No.IITP-2023-2020-0-01602,ITRC (Information Technology Research Center)support program,50%).
文摘Containerization is a fundamental component of modern cloud-native infrastructure,and Kubernetes is a prominent platform of container orchestration systems.However,containerization raises significant security concerns due to the nature of sharing a kernel among multiple containers,which can lead to container breakout or privilege escalation.Kubernetes cannot avoid it as well.While various tools,such as container image scanning and configuration checking,can mitigate container workload vulnerabilities,these are not foolproof and cannot guarantee perfect isolation or prevent every active threat in runtime.As such,a policy enforcement solution is required to tackle the problem,and existing solutions based on LSM(Linux Security Module)frameworks may not be adequate for some situations.To address this,we propose an enforcement system based on BPF-LSM,which leverages eBPF(extended Berkeley Packet Filter)technology to provide fine-grained control and dynamic adoption of security policies.In this paper,we compare different LSM implementations to highlight the challenges of current enforcement solutions before detailing the design of our eBPF-based Kubernetes Runtime Instrumentation and Enforcement System(KRSIE).Finally,we evaluate the effectiveness of our system using a real-world scenario,as measuring the performance of a policy enforcement system is a complex task.Our results show that KRSIE can successfully control containers’behaviors using LSM hooks at container runtime,offering improved container security for cloud-native infrastructure.
基金supported by the National Natural Science Foundation of China(61873030,62002019).
文摘In a cloud-native era,the Kubernetes-based workflow engine enables workflow containerized execution through the inherent abilities of Kubernetes.However,when encountering continuous workflow requests and unexpected resource request spikes,the engine is limited to the current workflow load information for resource allocation,which lacks the agility and predictability of resource allocation,resulting in over and underprovisioning resources.This mechanism seriously hinders workflow execution efficiency and leads to high resource waste.To overcome these drawbacks,we propose an adaptive resource allocation scheme named adaptive resource allocation scheme(ARAS)for the Kubernetes-based workflow engines.Considering potential future workflow task requests within the current task pod’s lifecycle,the ARAS uses a resource scaling strategy to allocate resources in response to high-concurrency workflow scenarios.The ARAS offers resource discovery,resource evaluation,and allocation functionalities and serves as a key component for our tailored workflow engine(KubeAdaptor).By integrating the ARAS into KubeAdaptor for workflow containerized execution,we demonstrate the practical abilities of KubeAdaptor and the advantages of our ARAS.Compared with the baseline algorithm,experimental evaluation under three distinct workflow arrival patterns shows that ARAS gains time-saving of 9.8% to 40.92% in the average total duration of all workflows,time-saving of 26.4% to 79.86% in the average duration of individual workflow,and an increase of 1% to 16% in centrol processing unit(CPU)and memory resource usage rate.
文摘Nomadic Vehicular Cloud(NVC)is envisaged in this work.The predo-minant aspects of NVC is,it moves along with the vehicle that initiates it and functions only with the resources of moving vehicles on the heavy traffic road without relying on any of the static infrastructure and NVC decides the initiation time of container migration using cell transmission model(CTM).Containers are used in the place of Virtual Machines(VM),as containers’features are very apt to NVC’s dynamic environment.The specifications of 5G NR V2X PC5 interface are applied to NVC,for the feature of not relying on the network coverage.Nowa-days,the peak traffic on the road and the bottlenecks due to it are inevitable,which are seen here as the benefits for VC in terms of resource availability and residual in-network time.The speed range of high-end vehicles poses the issue of dis-connectivity among VC participants,that results the container migration failure.As the entire VC participants are on the move,to maintain proximity of the containers hosted by them,estimating their movements plays a vital role.To infer the vehicle movements on the road stretch and initiate the container migration prior enough to avoid the migration failure due to vehicles dynamicity,this paper proposes to apply the CTM to the container based and 5G NR V2X enabled NVC.The simulation results show that there is a significant increase in the success rate of vehicular cloud in terms of successful container migrations.
基金Supported by National Natural Science Foundation of China(32160086,32160287,31900271)Key Project of Guizhou Provincial Science and Technology Fund(QKHJC[2019]1455)+1 种基金Central Government Supporting Local Science and Technology Development Fund Project(QKZYD[2021]4010)Undergraduate Innovation and Entrepreneurship Training Program(S202110665031,S202310665002,S202310665012).
文摘Based on the principle of asexual reproduction,a kind of scale breeding and reproduction technique of Ficus tikoua Bur.container seedlings was explored by using the characteristics of strong adaptability to the environment and fast growth and reproduction.Using non-woven bag as a breeding container for seedlings,the scale breeding and reproduction technique of F.tikoua container seedlings was summarized through the important links of seedling bed construction,seedling collection,soil configuration,container selection,cutting cultivation,field management,and disease and pest control.This technique can achieve differential,massive and sustainable efficient breeding and reproduction of F.tikoua seedlings in a short time.
文摘【应用背景】快速射电暴(Fast Radio Burst,FRB)搜寻是500米口径球面射电望远镜(FAST)的重要科学目标之一,其计算复杂度高,数据量大,当前算法GPU利用率偏低,数据处理需较多的人工介入操作。【目的】在不修改算法实现的前提下,实现进程级GPU并行优化,提高GPU整体资源利用率,简化算法运行调度,支持利用自动化脚本驱动计算过程。【方法】利用容器化封装FRB搜寻算法,结合GPU聚合技术实现多个FRB搜寻计算容器的多进程并行,支持GPU闲时复用。通过容器化封装屏蔽了GPU调用、依赖库管理等技术细节,减少人工介入操作。【结果】算法实验结果表明,在不修改原始算法、不增加GPU资源的前提下,将单GPU绑定6个计算进程,并行优化可实现FRB搜寻算法的加速比达到5.3,并行效率达到0.88,取得良好的并行效果。【结论】基于容器化封装及进程级GPU聚合的并行优化,可实现GPU利用率及计算效率的提升,有效支持自动化处理。该方法还具有良好的通用性,可适用于类似应用的并行优化。
基金supported by the National Natural Science Foundation of China (Grant No.11902157)Natural Science Foundation of Jiangsu Province (Grant No.BK20180417)the Scientific and Technological Innovation Project of Army Engineering Univeristy of PLA (Grant No.KYGYZXJK150025)。
文摘An innovative multi-layer composite explosion containment vessel(CECV)utilizing a sliding steel platealuminum honeycomb-fiber cloth sandwich is put forward to improve the anti-explosion capacity of a conventional single-layer explosion containment vessel(SECV).Firstly,a series of experiments and finite element(FE)simulations of internal explosions are implemented to understand the basic anti-explosion characteristics of a SECV and the rationality of the computational models and methods is verified by the comparison between the experimental results and simulation results.Based on this,the CECV is designed in detail and a variety of FE simulations are carried out to investigate effects of the sandwich structure,the explosive quantity and the laying mode of the fiber cloth on anti-explosion performance and dynamic response of the CECV under internal explosions.Simulation results indicate that the end cover is the critical position for both the SECV and CECV.The maximum pressure of the explosion shock wave and the maximum strain of the CECV can be extremely declined compared to those of the SECV.As a result,the explosive quantity the CECV can sustain is up to 20 times of that the SECV can sustain.Besides,as the explosive quantity increases,the internal pressure of the CECV keeps growing and the plastic deformation and failure of the sandwich structure become more and more severe,yielding plastic strain of the CECV in addition to elastic strain.The results also reveal that the laying angles of the fiber cloth's five layers have an impact on the anti-explosion performance of the CECV.For example,the CECV with fiber cloth layered in 0°/45°/90°/45°/0°mode has the optimal anti-capacity,compared to 0°/0°/0°/0°/0°and 0°/30°/60°/30°/0°modes.Overall,owing to remarkable anti-explosion capacity,this CECV can be regarded as a promising candidate for explosion resistance.