This paper is concerned with the optimization of the workforce scheduling for solving maintenance problems. To achieve this aim an optimsation software for (5, 7) problem was developed. The programme was written in Qu...This paper is concerned with the optimization of the workforce scheduling for solving maintenance problems. To achieve this aim an optimsation software for (5, 7) problem was developed. The programme was written in Quick Basic. The software was designed to produce a seven day schedule for organization operating a seven day week. Hence organization operating a five day schedule wishing to change to a seven day schedule we find this software very useful. The Quick-Basic computer programme was based on Alfares [1, 2] algorithm for solving (5,7) schedule problem. Data collected from Afam power station, Nigeria was used as input data. The test result shows the software is capable of determining workforce size and assigning workers to day-off pattern. The seven-day schedule produced savings of 11% maintenance labour cost when compared with the 5-day schedule currently being practiced by the Power station [3].展开更多
In this paper, the storage capacity of communication among cores and processors is taken into account and a maximum D-value-first algorithm is proposed. By improving the hardware parallelism in the task execution proc...In this paper, the storage capacity of communication among cores and processors is taken into account and a maximum D-value-first algorithm is proposed. By improving the hardware parallelism in the task execution process, the maximum storage requirements for communication are minimized. Experimental results with various directed acyclic graph models showed that compared with the earliest-task-first algorithm, the storage requirements for communication were reduced by 22.46%, on average, while the average of makespan only increased by 0.82%,.展开更多
The crowdsourcing, as a service pattern in cloud environment, usually aims at the cross-disciplinary cooperation and creating value together with customers and becomes increasingly prevalent. Software process, as a ki...The crowdsourcing, as a service pattern in cloud environment, usually aims at the cross-disciplinary cooperation and creating value together with customers and becomes increasingly prevalent. Software process, as a kind of software development and management strategy, is defined as a series of activities implemented by software life cycle and provides a set of rules for various phases of the software engineering to achieve the desired objectives. With the current software development cycle getting shorter, facing more frequent needs change and fierce competition, a new resource management pattern is proposed to respond to these issues agilely by introducing the crowdsourcing service to agile software development for pushing the agility of software process. Then, a user-oriented resource scheduling method is proposed for rational use of various resources in the process and maximizing the benefits of all parties. From the experimental results, the proposed pattern and resources scheduling method reduces greatly the resource of project resource manager and increases the team resource utilization rate, which greatly improves the agility of software process and delivers software products quickly in crowdsourcing pattern.展开更多
In order to solve the hybrid and dependent task scheduling and critical source allocation problems, a task scheduling algorithm has been developed by first presenting the tasks, and then describing the hybrid and depe...In order to solve the hybrid and dependent task scheduling and critical source allocation problems, a task scheduling algorithm has been developed by first presenting the tasks, and then describing the hybrid and dependent scheduling algorithm and deriving the predictable schedulability condition. The performance of this agorithm was evaluated through simulation, and it is concluded from the evaluation results that the hybrid task scheduling subalgorithm based on the comparison factor can be used to solve the problem of aperiodic task being blocked by periodic task in the traditional operating system for a very long time, which results in poor scheduling predictability; and the resource allocation subalgorithm based on schedulability analysis can be used to solve the problems of critical section conflict, ceiling blocking and priority inversion; and the scheduling algorithm is nearest optimal when the abortable critical section is 0.6.展开更多
The software-based computer numerical control(CNC) system includes three types of tasks: periodic real-time tasks, aperiodic real-time tasks, and non-real-time tasks. The tasks are characterized by concurrency, hyb...The software-based computer numerical control(CNC) system includes three types of tasks: periodic real-time tasks, aperiodic real-time tasks, and non-real-time tasks. The tasks are characterized by concurrency, hybridization, and correlation, which make system implementation difficult. The conventional scheduling algorithm can not meet the demands of system implementation in the software-based CNC system completely. The uncertainty factors when running real-time tasks affect control performance by degrading manufacturing accuracy as a result of system resource and processor use restrictions. To address the technical difficulty of embedded system implementation, a novel fuzzy feedback scheduling algorithm based on output jitter of key real-time tasks for a software-based CNC system is proposed. Time characteristics, such as sampling jitter, input-output jitter, and non-schedulability are discussed, followed by quantification through simulations of the impact of time characteristics on manufacturing accuracy. On the basis of this research, the scheduler architecture is designed, and then the algorithm table is calculated. When the system resource changes, the key periodic real-time tasks meet their deadlines by means of dynamically adjusting the task period. The simulated results show that the machining precision rises by an order of magnitude for the proposed scheduler in resource-constrained software-based CNC systems. Moreover, unlike conventional feedback scheduling methods, the algorithm in this paper does not rely on the availability of task execution times and is easy to implement while incurring only a small overhead.展开更多
软件定义网络(software-defined networks,SDN)流量调度提升网络性能和资源利用率、实现节能和负载均衡至关重要.传统的多目标优化算法在高流量和网络动态性增加的情况下显著影响算法的收敛速度,难以满足复杂网络环境的多样化需求.针对...软件定义网络(software-defined networks,SDN)流量调度提升网络性能和资源利用率、实现节能和负载均衡至关重要.传统的多目标优化算法在高流量和网络动态性增加的情况下显著影响算法的收敛速度,难以满足复杂网络环境的多样化需求.针对此问题,提出了一种基于深度强化学习的流量预测在线路由算法——OTPR-DRL:根据流量特征预测关键流和普通流,结合网络状态和流量信息建立线性规划问题获得关键流路由的最优解.为满足普通流不同服务质量(quality of service,QoS)需求,引入通用效用函数实现多目标优化,通过多智能体和优先级经验回放机制为普通流选择路由.实验结果表明,在高流量强度下,OTPR-DRL与现有的算法相比,提高了收敛速度,至少降低了10.26%的网络传输时延,3.09%的丢包率,提高了1.70%的吞吐率.展开更多
文摘This paper is concerned with the optimization of the workforce scheduling for solving maintenance problems. To achieve this aim an optimsation software for (5, 7) problem was developed. The programme was written in Quick Basic. The software was designed to produce a seven day schedule for organization operating a seven day week. Hence organization operating a five day schedule wishing to change to a seven day schedule we find this software very useful. The Quick-Basic computer programme was based on Alfares [1, 2] algorithm for solving (5,7) schedule problem. Data collected from Afam power station, Nigeria was used as input data. The test result shows the software is capable of determining workforce size and assigning workers to day-off pattern. The seven-day schedule produced savings of 11% maintenance labour cost when compared with the 5-day schedule currently being practiced by the Power station [3].
基金Supported by the National Natural Science Foundation of China(No.61179045 and No.61350009)
文摘In this paper, the storage capacity of communication among cores and processors is taken into account and a maximum D-value-first algorithm is proposed. By improving the hardware parallelism in the task execution process, the maximum storage requirements for communication are minimized. Experimental results with various directed acyclic graph models showed that compared with the earliest-task-first algorithm, the storage requirements for communication were reduced by 22.46%, on average, while the average of makespan only increased by 0.82%,.
基金Projects(61304184,61672221)supported by the National Natural Science Foundation of ChinaProject(2016JJ6010)supported by the Hunan Provincial Natural Science Foundation of China
文摘The crowdsourcing, as a service pattern in cloud environment, usually aims at the cross-disciplinary cooperation and creating value together with customers and becomes increasingly prevalent. Software process, as a kind of software development and management strategy, is defined as a series of activities implemented by software life cycle and provides a set of rules for various phases of the software engineering to achieve the desired objectives. With the current software development cycle getting shorter, facing more frequent needs change and fierce competition, a new resource management pattern is proposed to respond to these issues agilely by introducing the crowdsourcing service to agile software development for pushing the agility of software process. Then, a user-oriented resource scheduling method is proposed for rational use of various resources in the process and maximizing the benefits of all parties. From the experimental results, the proposed pattern and resources scheduling method reduces greatly the resource of project resource manager and increases the team resource utilization rate, which greatly improves the agility of software process and delivers software products quickly in crowdsourcing pattern.
文摘In order to solve the hybrid and dependent task scheduling and critical source allocation problems, a task scheduling algorithm has been developed by first presenting the tasks, and then describing the hybrid and dependent scheduling algorithm and deriving the predictable schedulability condition. The performance of this agorithm was evaluated through simulation, and it is concluded from the evaluation results that the hybrid task scheduling subalgorithm based on the comparison factor can be used to solve the problem of aperiodic task being blocked by periodic task in the traditional operating system for a very long time, which results in poor scheduling predictability; and the resource allocation subalgorithm based on schedulability analysis can be used to solve the problems of critical section conflict, ceiling blocking and priority inversion; and the scheduling algorithm is nearest optimal when the abortable critical section is 0.6.
基金supported by National Natural Science Foundation of China(Grant No.50875090,Grant No.50905063)National Hi-tech Research and Development Program of China(863 Program,Grant No.2009AA4Z111)China Postdoctoral Science Foundation (Grant No.20090460769)
文摘The software-based computer numerical control(CNC) system includes three types of tasks: periodic real-time tasks, aperiodic real-time tasks, and non-real-time tasks. The tasks are characterized by concurrency, hybridization, and correlation, which make system implementation difficult. The conventional scheduling algorithm can not meet the demands of system implementation in the software-based CNC system completely. The uncertainty factors when running real-time tasks affect control performance by degrading manufacturing accuracy as a result of system resource and processor use restrictions. To address the technical difficulty of embedded system implementation, a novel fuzzy feedback scheduling algorithm based on output jitter of key real-time tasks for a software-based CNC system is proposed. Time characteristics, such as sampling jitter, input-output jitter, and non-schedulability are discussed, followed by quantification through simulations of the impact of time characteristics on manufacturing accuracy. On the basis of this research, the scheduler architecture is designed, and then the algorithm table is calculated. When the system resource changes, the key periodic real-time tasks meet their deadlines by means of dynamically adjusting the task period. The simulated results show that the machining precision rises by an order of magnitude for the proposed scheduler in resource-constrained software-based CNC systems. Moreover, unlike conventional feedback scheduling methods, the algorithm in this paper does not rely on the availability of task execution times and is easy to implement while incurring only a small overhead.
文摘软件定义网络(software-defined networks,SDN)流量调度提升网络性能和资源利用率、实现节能和负载均衡至关重要.传统的多目标优化算法在高流量和网络动态性增加的情况下显著影响算法的收敛速度,难以满足复杂网络环境的多样化需求.针对此问题,提出了一种基于深度强化学习的流量预测在线路由算法——OTPR-DRL:根据流量特征预测关键流和普通流,结合网络状态和流量信息建立线性规划问题获得关键流路由的最优解.为满足普通流不同服务质量(quality of service,QoS)需求,引入通用效用函数实现多目标优化,通过多智能体和优先级经验回放机制为普通流选择路由.实验结果表明,在高流量强度下,OTPR-DRL与现有的算法相比,提高了收敛速度,至少降低了10.26%的网络传输时延,3.09%的丢包率,提高了1.70%的吞吐率.