Design of robust model-based controllers via parametric programming

In this paper a method is presented for deriving the explicit robust model-based optimal control law for constrained linear dynamic systems. The controller is derived off-line via parametric programming before any actual process implementation takes place. The proposed control scheme guarantees feasible operation in the presence of bounded input uncertainties by (i) explicitly incorporating in the controller design stage a set of feasibility constraints and (ii) minimizing the nominal performance, or the expectation of the performance over the uncertainty space. An extension of the method to problems involving target point tracking in the presence of persistent disturbances is also discussed. The general concept is illustrated with two examples.     

A practical implementation of stochastic programming: an application to the evaluation of option contracts in supply chains

Stochastic programming is a powerful analytical method in order to solve sequential decision-making problems under uncertainty. We describe an approach to build such stochastic linear programming models. We show that algebraic modeling languages make it possible for non-specialist users to formulate complex problems and have solved them by powerful commercial solvers. We illustrate our point in the case of option contracts in supply chain management and propose a numerical analysis of performance. We propose easy-to-implement discretization procedures of the stochastic process in order to limit the size of the event tree in a multi-period environment.     

A functional correspondence between call-by-need evaluators and lazy abstract machines

We bridge the gap between compositional evaluators and abstract machines for the lambda-calculus, using closure conversion, transformation into continuation-passing style, and defunctionalization of continuations. This article is a followup of our article at PPDP 2003, where we consider call by name and call by value. Here, however, we consider call by need.We derive a lazy abstract machine from an ordinary call-by-need evaluator that threads a heap of updatable cells. In this resulting abstract machine, the continuation fragment for updating a heap cell naturally appears as an ‘update marker’, an implementation technique that was invented for the Three Instruction Machine and subsequently used to construct lazy variants of Krivine's abstract machine. Tuning the evaluator leads to other implementation techniques such as unboxed values. The correctness of the resulting abstract machines is a corollary of the correctness of the original evaluators and of the program transformations used in the derivation.     

A joint GA+DP approach for single burn-in oven scheduling problems with makespan criterion

This research is motivated by the scheduling problem found in the burn-in operation of semiconductor final testing, where jobs are associated with release times, processing times, and sizes. The burn-in ovens are modeled as batch-processing machines which can process a batch of several jobs as long as the total sizes of the jobs do not exceed the machine capacity, and the processing time of a batch is equal to the longest time among all the jobs in the batch. Moreover, this paper attempts to schedule jobs on a single batch-processing machine to minimize makespan. A joint GA+DP algorithm is proposed involving two stages: (1) the formation of job sequence by genetic algorithm operators, and (2) the formation of batches by a dynamic programming algorithm. Computational experiments are given to examine the performance of the proposed algorithm. The experimental results indicate that the joint GA+DP approach has well improved on all instances with respect to solution quality and runtime.     

用混沌优化方法进行平面四杆机构的函数发生器综合

利用混沌运动的遍历性、内在随机性、“规律性”等特点，结合MATLAB5．3．1高级程序设计语言的优化工具箱，提出了一种混沌约束优化算法。运用该算法编写了MATLAB程序，对平面四杆机构的函数发生器综合问题进行了研究，从而找到了实现最大精确点时该问题的全部解，为实际机构的设计提供了多种选择方案。     

基于球面铣削的数控编程方法

针对球面的数控铣削问题,对比地分析了自动编程与手工编程的优劣。在手工编程过程中,突出了宏指令编程的技巧,为快速编写数控程序提供了参考。     

综合负荷聚合商参与的配电—气能源系统供需互动均衡模型

在综合能源系统背景下,提出一种基于主从博弈机制的配电—气能源系统与多个综合负荷聚合商的互动均衡模型。考虑次日能源价格的制定,配电—气系统以总利润最大化为目标求解日前最优能流。在价格机制作用下,综合负荷聚合商通过优化能源配置降低自身能源购置成本,从而实现配电—气系统与综合负荷聚合商的互利共赢。为求取主从博弈均衡解,采用二阶锥松弛(SOCP)和罚凸凹过程(PCCP)消除配电—气系统优化模型中的非凸源,并应用KKT条件和强对偶理论将原模型转化为单层凸优化模型。由此通过迭代求解混合整数二阶锥规划问题逐渐缩紧配气网管道气流松弛域,最终获得博弈均衡解。最后,以IEEE 33节点配电网和20节点配气网构成的系统为例进行仿真说明,所得结果验证了文中模型及方法的有效性。     

基于机会约束规划的多PET互联的交直流配电网日前优化调度

随着电力电子技术的发展,基于电力电子变压器(power electronic transformer,PET)构建可实现大范围互联的交直流配电网成为新的发展趋势。首先基于多PET应用于交直流配电网的应用场景,对其柔性调节作用进行了分析;其次,计及分布式电源日前预测出力的不确定性,构建了基于机会约束规划的多PET互联的交直流配电网日前优化调度模型;再次,利用蒙特卡洛方法模拟分布式电源出力的不确定性,采用粒子群优化算法对所提出的运行优化模型进行求解;最后,基于改进的IEEE 33节点算例对所提出的优化模型进行分析,通过与确定性运行优化模型进行比较,验证了所提模型的有效性和正确性。     

Modeling and analysis of workpiece stability based on the linear programming method

After being located on a machine bed, a workpiece will be subject to gravity and cutting forces during the machining operation. In order to keep the locating precision as well as the production safety, it is necessary to maintain the workpiece stability. In this paper, a linear programming method is proposed for stability analysis of the workpiece. Based on the linear approximation of the friction cone, a quantitative criterion is established to verify the workpiece stability in association with the rationality of the clamping sequence, magnitude of clamping forces and clamping placement. This criterion allows designers to plan reasonably the clamping sequence, magnitude of clamping forces as well as clamping placement. Compared with existing methods, the main advantage of this approach lies in that the sophisticated computing of contact forces between fixture elements and the workpiece is avoided. In this work, both friction and frictionless cases can be easily taken into account in stability analysis. Mathematical formulations of the method are given and some numerical tests are finally demonstrated to validate the proposed method.     

进化规划在控制混沌中的应用

提出基于进化规划引导混沌轨道的新方法，使混沌系统在微小扰动作用下，能迅速从某一给定的初始点达到要求的不动点附近区域，达到加快控制混沌的目的。对引导混沌Henon系统轨道进行了数值仿真，结果表明效果良好。