并行工程中资源冲突与任务调度的关系研究

发布时间：2018-03-24 16:43

本文选题：并行工程　切入点：资源冲突　出处：《西安电子科技大学》2014年硕士论文

【摘要】：并行工程中为了实现并行化从而缩短工程时间要考虑到两个方面,即挖掘任务之间的并行性和控制任务的粒度。而在并行工程中由于多功能小组工作性质的差异,在产品开发阶段任务规划的交叠和冲突经常出现,由此产生了许多信息冲突,而在任务调度中资源冲突又对工程具有较大制约性。为解决这些问题,保证合理利用资源及尽量缩短工期,本文对并行工程中的资源进行了分类和描述,且主要研究对象为其中的非消耗性资源;然后分析这种资源在并行工程中产生的资源冲突,并结合实例分别讨论了在任务分解和任务调度过程中存在的资源冲突,根据任务分解中资源冲突的存在形式,将其定义为过程信息资源冲突,本文用WBS或DSM进行基本任务分解后,使用DSM表示其任务结构,并对该DSM进行优化,且在该优化过程中尽力消解或弱化过程信息资源冲突;针对任务调度中出现的资源冲突,给出能够解决这些资源冲突的消解算法。本文应用任务分解消解过程信息资源冲突时,首先详细讨论了资源冲突、任务并行度和任务粒度三者之间的关系,然后定义了原子任务和复合任务;以此为根据给出了任务模型和任务分解的原则,并给出了任务分解的约束函数;最后针对基本任务分解后的DSM模型,用行列变换的方法对其优化,从而达到消解或弱化冲突的目的,并在此基础上形成了有效的任务划分方案,为任务的调度奠定了良好的基础。在基于任务调度过程对配置资源产生的冲突进行消解时,本文结合工期约束、资源约束和所调度任务的紧前、紧后任务约束给出了任务调度的基本模型。并结合设计结构矩阵和向量的特性,给出了表示任务之间时序关系的反设计结构矩阵,资源—任务匹配矩阵后,本文给出了在任务调度中基于优先任务和基于空闲资源调整这两种资源冲突消解的方法,针对优先任务给出了评价任务优先级的原则,针对空闲资源给出了优先满足配置资源的任务数量最大化和资源利用率最高的两种策略。由此,本文以前面给出的任务调度模型为依据,配合使用这两种资源冲突消解方法,即得出了本文的基于任务调度的配置资源冲突消解的方案。最后把本文所得出的冲突消解方案用于机械产品设计的实例中,成功地对任务划分和任务调度过程的资源冲突进行了消解,验证了该方法的有效性,体现了本文研究内容的实用性和价值性。
[Abstract]:In order to realize parallelism and shorten engineering time, two aspects should be considered in concurrent engineering, that is, mining the parallelism between tasks and controlling the granularity of tasks. In the product development phase, the overlapping and conflict of task planning often appear, resulting in a lot of information conflicts, but in task scheduling, resource conflict is more restrictive to the project. To solve these problems, In this paper, the resources in concurrent engineering are classified and described, and the main research object is the nonexpendable resources, and then the conflict of resources in concurrent engineering is analyzed. The resource conflicts in the process of task decomposition and task scheduling are discussed with examples. According to the existing forms of resource conflicts in task decomposition, they are defined as process information resource conflicts. In this paper, we use WBS or DSM to decompose the basic tasks, then use DSM to express the task structure, and optimize the DSM, and try to resolve or weaken the process information resource conflicts in the optimization process. In this paper, the relationship among resource conflict, task parallelism and task granularity is discussed in detail. Then, the atomic task and composite task are defined, the task model and task decomposition principle are given, and the constraint function of task decomposition is given. Finally, the DSM model after basic task decomposition is given. The method of rank and column transformation is used to optimize it so as to resolve or weaken the conflict, and on this basis, an effective task division scheme is formed. It lays a good foundation for task scheduling. When the conflict caused by configuration resources is resolved in the process of task scheduling, this paper combines duration constraints, resource constraints and the compactness of scheduled tasks. The basic model of task scheduling is given, and the inverse design structure matrix and the resource-task matching matrix are given to express the temporal relationship between tasks, combined with the characteristics of the design structure matrix and the vector. In this paper, two methods to resolve the conflict between priority tasks and idle resources in task scheduling are given, and the principle of evaluating task priority is given for priority tasks. In this paper, two strategies of maximizing the number of tasks and the highest utilization of resources are given for the free resources. Therefore, based on the task scheduling model given earlier, this paper uses these two methods to resolve the conflict between the two kinds of resources. In this paper, the solution of resource conflict resolution based on task scheduling is obtained. Finally, the conflict resolution scheme is used in the design of mechanical products. The resource conflicts in task partition and task scheduling process are successfully resolved, and the effectiveness of this method is verified, which reflects the practicability and value of the research content in this paper.
【学位授予单位】：西安电子科技大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TB472

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