基于多Agent和进化算法的作业线调度研究

作业线调度是集装箱码头生产调度中最为关键的一个环节。文中将在充分分析与研究集装箱码头装卸作业信息流动的基础上,针对岸边作业线调度问题以及国内作业线系统的不足,建立模型辅助决策,帮助调度员快速、准确、安全、合理地进行岸桥调度的决策。在文中,充分地考虑了泊位、船舶、岸桥等集装箱设备及其协调,利用并合理地配置了这些码头资源,将引用多Agent技术协调作业线调度,并使用进化算法计算并安排岸桥来进行作业调度,建立基于多Agent和进化算法的集装箱码头作业线调度智能化系统。     

基于改进的RA逄法的混合Flowshop调度问题的求解

针对混合Flowshop系统的最小化akespan调度问题，提出基于改进的RA斜度指标的启发式算法来对工件进行排序，采用FAM算法来分配设备，并给出最优值的下界检验该算法。仿真结果表明，该方法优于目前最好的启发式算法，能较好地解决混合Flowshop的调度问题。     

EPA通信调度测试方法与实现技术

介绍了EPA通信协议模型和EPA通信调度规程，根据通信调度的原理和要求，研究了EPA协议确定性调度的测试原理，提出了测试EPA确定性调度的方法和系统结构，对调度偏差和调度顺序分别论述了其相应的测试流程。通过测试系统的实际应用证明这种测试方法能够准确地测试被测设备调度实体的实现与EPA标准的符合程度。     

Job-Shop调度问题的仿真研究

Job-Shop是离散事件系统中典型的调度问题，通过计算机仿真能够动态地展现Job-Shop车间的状态，分析在不同调度方法下的系统性能，并运用知识和经验去选择合适的调度方法，从而改善调度性能。本文构造了Job-Shop的离散事件仿真模型，设计了基于事件驱动的仿真策略，并讨论了优先调度准则，为解决这一问题提供了一种现实可行的思路与方法。     

轨道交通调度算法仿真平台的设计

该文着重从系统的角度介绍了轨道交通调度算法实物仿真平台的设计。整个仿真系统被划分为算法层、通信层和执行层三个功能层次，各层次由相关软硬件设备组建，通过标准接口连接，构成了一个具有很强伸缩性的系统，能较真实地模拟实际轨道交通环境。该仿真平台在实用中工作稳定、操作简便，提高了所研制交通调度算法的可信度。     

基于时间约束集的集束型设备群调度方法

随着300mm晶圆的加工技术问世,工业界开始采用一种全新的晶圆制造设备——集束型设备群(Multi-cluster tools).对于单个集束型设备(Single-cluster tools)调度研究已比较成熟,并提出了多种调度方法,然而对于集束型设备群调度研究尚处在一个起步阶段. 本文对带有驻留约束且具有多种晶圆类型的集束型设备群的调度问题进行了研究,在引入时间约束集概念的基础上建立了调度模型, 同时,提出了一种逐级回溯的调度方法,并对调度算法进行了仿真实验分析. 仿真结果表明本文提出的算法是有效且可行的.     

基于加权朴素贝叶斯算法的调度指挥态势感知模块设计

针对调度与现场频繁电话沟通调度操作进程信息,以及无法提供给现货市场较精确的设备停复电时间作为边界条件的问题,将大数据挖掘理念引入了调度指挥领域,在南方电网调度指挥控制系统（Power Dispatch Command Control System,DCCS）的基础上,设计了一种对调度指挥态势进行实时感知的功能模块。该模块可通过DCCS获取调度员在业务准备关键节点的业务环境特征数据,采用加权朴素贝叶斯算法对调度员的实时忙碌程度进行挖掘,结合历史数据对忙碌系数进行匹配,并动态更新预计开展时间,得到结果后可传输至现货系统,作为节点电价计算的边界条件。此外,该模块还具备操作预约、操作通知、智能编排、态势展示等功能。模块上线后,减少了调度与现场有关操作信息的无谓沟通,所构建的数据模型也取得了较好的预测准确率。     

半导体制造系统仿真调度中的优化方法

基于仿真的调度方法通常需要进行大量的仿真或者采用好的规则以优化调度结果. 本 文建立了以减小平均在制品为优化目标的半导体制造系统的调度模型, 对模型进行分解和简 化. 把结论作为一个调度规则直接应用于仿真调度方法. 由于充分利用了系统全局的状态信 息, 可以有效地减少仿真的次数, 提高了仿真调度的优化能力.     

设备故障条件下柔性作业车间重调度方法

设备故障是生产实践中最为常见的一类不确定事件,它易对正常的生产计划造成影响。为了有效应对生产中的设备随机故障干扰,对设备随机故障条件下的柔性作业车间调度问题进行了研究,提出了一种基于组合策略的重调度方法。在重调度方法中,对重调度成本进行了系统分析并建立了重调度成本函数,设计了两种重调度策略,并结合免疫算法对遗传算法进行了改进,用于模型的求解计算。通过算例分析,验证了方法的可行性和有效性。实验结果表明,所提出方法能够更好地处理多种情况下的设备故障扰动。     

面向对旬有的智能化FMS调度仿真

该文在分析传统数学方法和实验仿真方法的基础上，提出了一个求解ＦＭＳ调度问题的智能决策系统，使用面向对象的方法，构造一个专家和仿真技术集成的调度模型，并进行了仿真实验分析。     

基于BP神经网络的网络控制系统调度

为了在复杂的网络环境下能更合理地分配网络资源,提出了利用BP神经网络,通过对网络调度器产生的历史和当前数据进行训练,预测调度器下周期可能产生的数据,进而对下一调度周期的死区大小进行调整。实验仿真表明,所设计的反馈调度器能进一步改善网络控制系统的性能,进一步提高应对负载变化的能力。     

Stability and Performance of List Scheduling With External Process Delays

Non-preemptive static priority list scheduling is a simple, low-overhead approach to scheduling precedence-constrained tasks in real-time multiprocessor systems. However, it is vulnerable to anomalous timing behavior caused by variations in task durations. Specifically, reducing the duration of one task can delay the starting time of another task. This phenomenon, called Scheduling Instability, can make it difficult or impossible to guarantee real-time deadlines. Several heuristic solutions to handle scheduling instability have been reported. This paper addresses three main limitations in the state of the art in schedule stabilization. First, each stabilization technique only applies to a narrowly defined class of systems. To alleviate this constraint, we present an Extended Scheduling Model encompassing a wide range of assumptions about the scheduling environment, and address the stability problem under this model. Second, existing stabilization methods are heuristics based on a partial understanding of the causes of instability. We therefore derive a set of General Instability Conditions which are both necessary and sufficient for instability to occur. Third, solutions to scheduling instability range from trivial constraints on the run-time dispatcher through complex transformations of the precedence graph. We present scheduling simulation results comparing the average performance of several inherently stable run-time dispatchers of widely varying levels of complexity. Results show that for representative real-time workloads, simple low-overhead dispatchers perform nearly as well as a complex minimally stabilized dispatcher. Thus, complex schedule stabilization methods may be unnecessary, or even detrimental, due to their high computational overhead.     

面向互联网计算资源共享的自适应调度模型

在面向互联网的计算资源共享平台中,如何把服务器端的子任务均匀地调度给大规模互联网环境下的志愿机运算是一个重要的研究问题。描述了该平台下的一个自适应并行调度模型。调度器处于服务器端与志愿机之间,缓解服务器端的访问瓶颈;服务器端首先根据调度器的负载对子任务进行第一次分派,在调度器端根据下属的志愿机的软硬信息再分配子任务。通过运行典型的BanchMark并行程序,把该调度策略与其他策略进行比较,验证了该调度模型针对粗粒度并行的主从（Master-Slave）风格并行应用可以获得较好的性能。     

TCPHA:一个新型的高性能基于内容调度系统

目前Web服务器集群的调度技术中,基于内容的调度是一种主流的调度技术,有很多的优势。但目前流行的基于内容的调度系统普遍存在系统可扩展性差,调度器性能瓶颈问题,而不能充分发挥基于内容调度的优势。该文研究实现了一种新型的基于内容调度系统TCPHA,它在操作系统内核工作,实现了一些最新的技术,如TCP Handoff技术、动态IP Tunnel技术、ARP过滤技术等。性能测试表明,相对于传统的基于内容调度系统,TCPHA有着更高的性能。     

TD—SCDMA无线通信系统在煤矿的应用

介绍了TD-SCDMA无线通信系统的总体设计方案以及该系统在华亭煤矿的具体装备和应用情况。TD-SCDMA无线通信系统可与有线调度通信系统配合,实现了井下移动作业人员与地面调度人员的通信;采用无线TA定位技术实现了对井下人员的精确定位,定位信息可显示在上位机界面。     

On the Design and Implementation of a Shared Memory Dispatcher for Partially Clairvoyant Schedulers

With the onset of distributed computing in hard real-time applications, the problem of assigning to, scheduling in, and executing jobs on processors, has received a lot of attention. Usually, real-time systems are embedded in closed loop reactive environments with uncertain behaviors and such systems take varying times to respond to such stimuli. One of the fundamental features of such systems is the presence of complex timing constraints between pairs of jobs. A secondary feature is the non-constant nature of the execution times of jobs. Real-time operating systems such as MARUTI can measure the interval within which the execution time varies (Mosse et al. In: Second IEEE Workshop on Experimental Distributed System, pp. 29–34., IEEE, 1990; Levi et al. 1989, ACM Special Interest Group Operat Syst 23(3):90–106). Partially clairvoyant scheduling was introduced in (Saksena, Parametric Scheduling in Hard Real-Time Systems. PhD thesis, University of Maryland, College Park, June 1994) to schedule jobs with varying execution times and non-trivial timing constraints. The schedulability of the job set is determined offline and a set of dispatch functions are produced from the given set of constraints if the job set is schedulable. The dispatch functions bind the start time of a job J to an interval that depends on the start and execution times of jobs sequenced before J. The online dispatcher of the system reads these dispatch functions and computes the interval within which a job can start without violating the constraints imposed on the system. In certain situations, the dispatcher fails to dispatch a job as the time to compute the dispatch functions associated with a job is greater than the interval within which the job needs to be dispatched. This phenomenon is called Loss of Dispatchability (Subramani, Duality in the Parametric Polytope and its Applications to a Scheduling Problem. PhD thesis, University of Maryland, College Park, August 2000). In this paper, we propose and implement a partially clairvoyant dispatching algorithm on a shared memory cluster with Concurrent Read Exclusive Write (CREW) architecture and contrast it with the sequential approach. For a preset number of processors, our approach has O(1) dispatch complexity while using a total of O(n ²) space, while the sequential approach requires Ω(n) time. The detailed implementation profile obtained clearly demonstrates the superiority of the multiprocessor approach to dispatching. We also address the issue of scalability of the dispatcher for increasing number of processors and show that job sets of different sizes require different number of processors. Finally, we demonstrate the effect of execution time on the dispatchability of schedules.     

Web服务器集群中TCP Handoff技术及其实现

在传统的Web服务器集群系统中,前端分发器由于通过的数据量太大容易形成瓶颈,进而影响系统的整体性能。该文利用TCPHandoff技术,分散了通过前端分发器的绝大部分网络流量,解决了Web服务器集群中前端分发器的瓶颈问题。通过在Linux环境下的原型系统实现和实验数据分析,证明了该技术的有效性。     

以促进电力调度员全面发展为目标的管理模式研究与应用

电力调度员是电网运行、操作和事故处理的指挥员。随着电网迅速发展,科技不断进步,管理日渐精细,除了电网运行指挥的常规工作外,调度员还担任了许多系统运行管理任务,包括：下级调度机构人员培训、调度处置预案编制等。对于调度员管理提升,如何通过机制创新,促进调度员全面发展,是新形式下调度专业管理培养的重要任务。本文介绍了G省首创的以促进调度员全面发展为目标,以量化积分管理为手段的创新管理模式,并介绍了实践效果。     

高可用性集群中的动态负载平衡应用研究

提出了一个基于性能预测的、计算连接权重的动态分配算法,以及网络调度器来实现高可用性集群中的动态负载平衡系统。该系统包括调度器、交互式会话支持单元等模块。测试表明,该系统能迅速、准确地找出最佳服务器来处理请求,在负载平衡的效能上有明显的提高,从而为接下来的服务等动作做好准备。     

An experimental study of processor thrashing in multiprocessor systems

A special occurrence of a phenomenon calledprocessor thrashing caused by processor lockouts within the dispatcher of a symmetric multiprocessor system is studied. Results derived from simulation experiments involving up to 16 processors show that the potential danger of processor thrashing can be reduced noticably by locking only parts of the dispatcher's data during a specific dispatcher operation. The algorithms and data structure of a highly efficient implementation are outlined based on this principle and its performance is compared with a simple monitor realization of a dispatcher.