检索结果-南通市图书馆

An adaptive SVM-based real-time scheduling mechanism and simulation for multiple-load carriers in automobile assembly lines

在线全文

学校读者我要写书评

暂无评论

International Journal of Modeling, Simulation, and Scientific Computing 2017年第4期8卷 151-174页

作者： Binghai Zhou Jiahui Xu School of Mechanical Engineering Tongji University Shanghai 201804P.R.China

Multiple-load carriers are widely introduced for material delivery in manufacturing *** real-time scheduling of multiple-load carriers is so complex that it deserves attention to pursue higher productivity and better system *** this paper,a support vector machine(SVM)-based real-time scheduling mechanism was proposed to tackle the scheduling problem of parts replenishment with multiple-load carriers in automobile assembly plants under dynamic *** SVM-based scheduling mechanism was trained first and then used to make the optimal real-time decisions between“wait”and“deliver”on the basis of real-time system *** objective function considering throughput and delivery distances was established to evaluate the system ***,a simulation model in eM-Plant software was developed to validate and compare the proposed SVM-based scheduling mechanism with the classic minimum batch size(MBS)*** simulated both the steady and dynamic environments which are characterized by the uncertainty of demands or scheduling *** simulation results demonstrated that the SVM-based scheduling mechanism could dynamically make optimal real-time decisions for multiple-load carriers and outperform the MBS heuristic as well.

关键词： Multiple-load carriers SVM material handling real-time scheduling simulation eM-Plant

Long-release-interval-first real-time scheduling algorithm and its schedulability test

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Southeast University(English Edition) 2006年第4期22卷 484-489页

作者：沈卓炜汪芸东南大学计算机网络和信息集成教育部重点实验室南京210096

To fulfill the requirements for hybrid real-time system scheduling, a long-release-interval-first （LRIF） real-time scheduling algorithm is proposed. The algorithm adopts both the fixed priority and the dynamic priority to assign priorities for tasks. By assigning higher priorities to the aperiodic soft real-time jobs with longer release intervals, it guarantees the executions for periodic hard real-time tasks and further probabilistically guarantees the executions for aperiodic soft real-time tasks. The schedulability test approach for the LRIF algorithm is presented. The implementation issues of the LRIF algorithm are also discussed. Simulation result shows that LRIF obtains better schedulable performance than the maximum urgency first （MUF） algorithm, the earliest deadline first （EDF） algorithm and EDF for hybrid tasks. LRIF has great capability to schedule both periodic hard real-time and aperiodic soft real-time tasks.

关键词： real-time scheduling schedulability test earliest deadline first maximum urgency first long release interval first

real-time Hybrid Flow Shop scheduling Approach in Smart Manufacturing Environment

在线全文

学校读者我要写书评

暂无评论

Complex System Modeling and Simulation 2021年第4期1卷 335-350页

作者： Xiuli Wu Zheng Cao Shaomin Wu Department of Logistics the School of Mechanical EngineeringUniversity of Science and Technology BeijingBeijing 100083China Kent Business School University of KentKentCT27FSUK.

Smart manufacturing in the“Industry 4.0”strategy promotes the deep integration of manufacturing and information technologies,which makes the manufacturing system a ubiquitous ***,the real-time scheduling of such a manufacturing system is a challenge faced by many decision *** deal with this challenge,this study focuses on the real-time hybrid flow shop scheduling problem(HFSP).First,the characteristic of the hybrid flow shop in a smart manufacturing environment is analyzed,and its scheduling problem is ***,a real-time scheduling approach for the HFSP is *** core module is to employ gene expression programming to construct a new and efficient scheduling rule according to the real-time status in the hybrid flow *** the scheduling rule,the priorities of the waiting job are calculated,and the job with the highest priority will be scheduled at this decision time point.A group of experiments are performed to prove the performance of the proposed *** numerical experiments show that the real-time scheduling approach outperforms other single-scheduling rules and the back-propagation neural network method in optimizing most objectives for different size ***,the contribution of this study is the proposal of a real-time scheduling approach,which is an effective approach for real-time hybrid flow shop scheduling in a smart manufacturing environment.

关键词： smart manufacturing real-time scheduling hybrid flow shop scheduling problem gene expression programming

Joint Algorithm of Message Fragmentation and No-Wait scheduling for time-Sensitive Networks

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

IEEE/CAA Journal of Automatica Sinica 2021年第2期8卷 478-490页

作者： Xi Jin Changqing Xia Nan Guan Peng Zeng Key Laboratory of Networked Control Systems Chinese Academy of SciencesShenyang 110016 Shenyang Institute of Automation Chinese Academy of SciencesShenyang 110016China Institutes for Robotics and Intelligent Manufacturing Chinese Academy of SciencesShenyang 110169China Department of Computing Hong Kong Polytechnic UniversityHong KongChina

time-sensitive networks(TSNs)support not only traditional best-effort communications but also deterministic communications,which send each packet at a deterministic time so that the data transmissions of networked control systems can be precisely scheduled to guarantee hard real-time ***-wait scheduling is suitable for such TSNs and generates the schedules of deterministic communications with the minimal network resources so that all of the remaining resources can be used to improve the throughput of best-effort ***,due to inappropriate message fragmentation,the realtime performance of no-wait scheduling algorithms is ***,in this paper,joint algorithms of message fragmentation and no-wait scheduling are ***,a specification for the joint problem based on optimization modulo theories is proposed so that off-the-shelf solvers can be used to find optimal ***,to improve the scalability of our algorithm,the worst-case delay of messages is analyzed,and then,based on the analysis,a heuristic algorithm is proposed to construct low-delay ***,we conduct extensive test cases to evaluate our proposed *** evaluation results indicate that,compared to existing algorithms,the proposed joint algorithm improves schedulability by up to 50%.

关键词： Message fragmentation networked control system real-time scheduling time sensitive network

Efficient schedulability analysis for mixed-criticality systems under deadline-based scheduling

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Aeronautics 2014年第4期27卷 856-866页

作者： Chen Yao Li Qiao Li Zheng Xiong Huagang School of Electronic and Information Engineering Beihang University

Safety-critical avionics systems which become more complex and tend to integrate multiple functionalities with different levels of criticality for better cost and power efficiency are subject to certifications at various levels of rigorousness. In order to simultaneously guarantee temporal constraints at all different levels of assurance mandated by different criticalities, novel scheduling techniques are in need. In this paper, a mixed-criticality sporadic task model with multiple virtual deadlines is built and a certification-cognizant dynamic scheduling approach referred as earliest virtual-deadline first with mixed-criticality（EVDF-MC） is considered, which exploits different relative deadlines of tasks in different criticality modes. As for the corresponding schedulability analysis problem, a sufficient and efficient schedulability test is proposed on the basis of demand-bound functions derived in the mixed-criticality scenario. In addition, a modified simulated annealing（MSA）-based heuristic approach is established for virtual deadlines assignment. Experiments performing simulations with randomly generated tasks indicate that the proposed approach is computationally efficient and competes well against the existing approaches.

关键词： Avionics systems Mixed-criticality real-time scheduling Schedulability analysis Simulated annealing

Reservation-based feedback scheduling of MPC tasks

在线全文

学校读者我要写书评

暂无评论

Journal of Systems Engineering and Electronics 2007年第1期18卷 132-136页

作者： Zhou Pingfang Xie Jianying Inst. of Aerospace Science and Technology Shanghai Jiaotong University Shanghai 200030 P.R. China Dept. of Automation Shanghai Jiaotong University Shanghai 200030 ER. China

A reservation-based feedback scheduling （FS-CBS） of a set of model predictive control （MPC） tasks is presented to optimize the global control performance subject to limited computational resource. Implemented as anytime algorithm, MPC task allows computation time to be traded for control performance. Each MPC task is assigned with a constant bandwidth server （CBS）, whose reserved processor time is adjusted dynamically. The FS-CBS is shown robust against the varying of execution time of MPC tasks at runtime. Simulation results illustrate its effectiveness.

关键词： real-time control system real-time scheduling Model predictive control

Implementation of an energy-efficient scheduling scheme based on pipeline flux leak monitoring networks

在线全文

学校读者我要写书评

暂无评论

Science in China(Series F) 2009年第9期52卷 1632-1639页

作者： ZHOU Peng YAO JiangHe PEI JiuLing College of Information Engineering Tarim University Alar Xinjiang 843300 China School of Mechanical and Electrical Engineering Tarim University Alar Xinjiang 843300 China

Flow against pipeline leakage and the pipe network sudden burst pipe to pipeline leakage flow for the application objects, an energy-efficient real-time scheduling scheme is designed extensively used in pipeline leak monitoring. The proposed scheme can adaptively adjust the network rate in real-time and reduce the cell loss rate, so that it can efficiently avoid the traffic congestion. The recent evolution of wireless sensor networks has yielded a demand to improve energy-efficient scheduling algorithms and energy-efficient medium access protocols. This paper proposes an energy-efficient real-time scheduling scheme that reduces power consumption and network errors on pipeline flux leak monitoring networks. The proposed scheme is based on a dynamic modulation scaling scheme which can scale the number of bits per symbol and a switching scheme which can swap the polling schedule between channels. Built on top of EDF scheduling policy, the proposed scheme enhances the power performance without violating the constraints of real-time streams. The simulation results show that the proposed scheme enhances fault-tolerance and reduces power consumption. Furthermore, that Network congestion avoidance strategy with an energy-efficient real-time scheduling scheme can efficiently improve the bandwidth utilization, TCP friendliness and reduce the packet drop rate in pipeline flux leak monitoring networks.

关键词： real-time scheduling dynamic modulation scaling reclaiming scheme EDF sensor networks

Improved Blocking time Analysis and Evaluation for the Multiprocessor Priority Ceiling Protocol

在线全文

学校读者我要写书评

暂无评论

Journal of Computer Science & Technology 2014年第6期29卷 1003-1013页

作者：杨茂林雷航廖勇 Furkan Rabee IEEE School of Information and Software Engineering University of Electronic Science and Technology of China CCF School of Computer Science and Engineering University of Electronic Science and Technology of China

The Multiprocessor Priority Ceiling Protocol （MPCP） is a classic suspension-based real-time locking protocol for partitioned fixed-priority （P-FP） scheduling. However, existing blocking time analysis is pessimistic under the P-FP ＋ MPCP scheduling, which negatively impacts the schedulability for real-time tasks. In this paper, we model each task as an alternating sequence of normal and critical sections, and use both the best-case execution time （BCET） and the worst-case execution time （WCET） to describe the execution requirement for each section. Based on this model, a novel analysis is proposed to bound shared resource requests. This analysis uses BCET to derive the lower bound on the inter-arrival time for shared resource requests, and uses WCET to obtain the upper bound on the execution time of a task on critical sections during an arbitrary time interval of △t. Based on this analysis, improved blocking analysis and its associated worst-case response time （WCRT） analysis are proposed for P-FP ＋ MPCP scheduling. Schedulability experiments indicate that the proposed method outperforms the existing methods and improves the schedulability significantly.

关键词： real-time scheduling multiprocessor scheduling locking protocol blocking analysis worst-case response time

End-to-End Utilization Control for Aperiodic Tasks in Distributed real-time Systems

在线全文

学校读者我要写书评

暂无评论

Journal of Computer Science & Technology 2007年第1期22卷 135-146页

作者：廖勇陈旭东熊光泽朱清新桑楠 real-time Systems Lab School of Computer Science and Engineering University of Electronic Science and Technology of China Chengdu 610054 China

An increasing number of DRTS （Distributed model. The key challenges of such DRTS are guaranteeing real-time Systems） are employing an end-to-end aperiodic task utilization on multiple processors to achieve overload protection, and meeting the end-to-end deadlines of aperiodic tasks. This paper proposes an end-to-end utilization control architecture and an IC-EAT （Integration Control for End-to-End Aperiodic Tasks） algorithm, which features a distributed feedback loop that dynamically enforces the desired utilization bound on multiple processors. IC-EAT integrates admission control with feedback control, which is able to dynamically determine the QoS （Quality of Service） of incoming tasks and guarantee the end-to-end deadlines of admitted tasks. Then an LQOCM （Linear Quadratic Optimal Control Model） is presented. Finally, experiments demonstrate that, for the end-to-end DRTS whose control matrix G falls into the stable region, the IC-EAT is convergent and stable. Moreover,it is capable of providing better QoS guarantees for end-to-end aperiodic tasks and improving the system throughput.

关键词： real-time scheduling end-to-end distributed real-time system feedback control scheduling aperiodic task