SPEM2XPDL模型转换研究*

将软件过程技术与工作流技术相结合,严格定义了SPEM2XPDL模型转换规则,设计并实现了一个SPEM2XPDL模型转换引擎.此引擎将SPEM描述的软件过程转换为符合工作流定义(XPDL)的工作流过程,从而可基于工作流管理系统对软件过程提供执行支持.SPEM模型经引擎转换后在工作流管理系统Shark上的成功执行表明了引擎的可用性.     

基于场景元模型的软件产品线追踪方法

针对软件产品线需求追踪方法进行了研究,基于软件产品线领域需求分析、设计、实现三个阶段的信息传播,提出了一种基于场景元模型的多层次软件产品线追踪模型,完整描述了追踪信息变化的整体框架;建立了需求—用例追踪矩阵、用例—动作追踪矩阵、动作—构件追踪矩阵;根据矩阵运算,描述了具体追踪实现过程,通过一个ATM案例验证了该方法对于软件产品线领域需求获取以及需求变更等问题的解决有较好的效果。     

Scheduling a dynamic job shop production system with sequence-dependent setups: An experimental study

This paper presents the salient aspects of a simulation-based experimental study of scheduling rules for scheduling a dynamic job shop in which the setup times are sequence dependent. A discrete event simulation model of the job shop system is developed for the purpose of experimentation. Seven scheduling rules from the literature are incorporated in the simulation model. Five new setup-oriented scheduling rules are proposed and implemented. Simulation experiments have been conducted under various experimental conditions characterized by factors such as shop load, setup time ratios and due date tightness. The results indicate that setup-oriented rules provide better performance than ordinary rules. The difference in performance between these two groups of rules increases with increase in shop load and setup time ratio. One of the proposed rules performs better for mean flow time and mean tardiness measures.     

Detailed design of a lattice composite fuselage structure by a mixed optimization method

In this article, a procedure for designing a lattice fuselage barrel is developed. It comprises three stages: first, topology optimization of an aircraft fuselage barrel is performed with respect to weight and structural performance to obtain the conceptual design. The interpretation of the optimal result is given to demonstrate the development of this new lattice airframe concept for the fuselage barrel. Subsequently, parametric optimization of the lattice aircraft fuselage barrel is carried out using genetic algorithms on metamodels generated with genetic programming from a 101-point optimal Latin hypercube design of experiments. The optimal design is achieved in terms of weight savings subject to stability, global stiffness and strain requirements, and then verified by the fine mesh finite element simulation of the lattice fuselage barrel. Finally, a practical design of the composite skin complying with the aircraft industry lay-up rules is presented. It is concluded that the mixed optimization method, combining topology optimization with the global metamodel-based approach, allows the problem to be solved with sufficient accuracy and provides the designers with a wealth of information on the structural behaviour of the novel anisogrid composite fuselage design.     

支持向量回归与常用近似模型的非线性预测性能比较研究

为降低计算成本和提高优化效率,工程实践中广泛应用近似模型拟合或预测非线性系统响应是研究的前沿与热点。引入支持向量回归方法,通过典型数值案例对比分析其与多项式响应面、kriging和径向基函数的非线性预测性能。利用箱线图直观的证明支持向量回归的非线性预测性能明显优于多项式响应面、kriging和径向基函数,且支持向量回归的预测精度对DOE的依赖性最弱,体现出良好的稳健性能,进一步验证了支持向量回归适用于非线性系统响应的近似建模。     

基于PRS元模型的粒子群优化算法及其应用*

针对传统粒子群算法优化黑箱模型过程中存在巨大计算开销的问题,提出一种基于PRS元模型的改进粒子群优化算法—PPSO算法。在该算法迭代过程中,构建PRS元模型,利用其最优值点辅助粒子种群的更新,此外仅选择元模型预估集中优值集的粒子进行目标函数的计算仿真。将PPSO算法与基本粒子群算法、混沌粒子群算法进行数值测试对比,并应用于模糊控制器的优化设计,仿真结果表明该算法可减少真实估值次数,提高优化搜索能力。     

MDA建模的AOP扩展策略及其比较

对于MDA横切于核心业务逻辑的关注点对封装的破坏的问题,本文给出把AOP引入到MDA的扩展策略和主要方法,并对不同的扩展策略进行了比较。     

一种状态图到B规格说明的自动转换方法研究实现

状态图是UML动态视图之一,主要描述对象的动态行为,但缺乏形式化的动态语义,不利于软件从需求到代码的自动化转换。B语言支持形式化规格说明,在MDA转换过程中,把UML状态图转换为B规格说明,可以使MDA中的需求表达得更为精确。基于此,提出了一种基于EMF的状态图到B规格说明的转换方法,设计了状态图和B抽象机的元模型,定义了元模型之间的转换规则,给出了该规则的ATL描述,最后在Eclipse平台实现了状态图到B规格说明的自动转化。该方法为MDA过程中获取形式化需求提供了一种新的途径。     

工作流过程元模型研究

介绍了工作流过程元模型的相关概念，着重分析了几种具有代表性的工作流过程元模型，提出了一种微型的、分层结构的、易于扩展的动态工作流过程元模型MINI，一种新的工作流模式即转移依赖分支模式被实现，最后介绍了MINI工作流管理系统。     

通用数据仓库元数据模型的研究

元数据及其管理是数据仓库技术的核心部分，数据仓库数据的使用及其相互间的关系迫切需要统一的元数据模型来描述。本文详细介绍了OMG推出的通用数据仓库元数据模型(CWM)的组成结构和底层技术标准，并讨论了这些技术标准与CWM之间的关系。