含风电场电力系统的有功优化潮流

提出了一种基于机会约束规划的风电并网系统的有功优化潮流模型和算法。引入了表示风电场发电功率和母线负荷的随机变量，以概率的形式描述约束条件（如线路潮流、节点电压、旋转备用以及稳态频率偏移等）。开发了基于遗传算法和随机模拟技术的计算程序。在IEEE30节点系统上的测试结果验证了文中所提方法的可行性。     

考虑谐波源随机过程的配电网络滤波装置优化配置

电力系统中非线性负荷所产生的谐波电流随时间的变化实际上是一种非平衡随机过程，因此文中提出了一种近似的处理方法，将随机过程适当地划分成若干个时间段，每人时段中将各谐波源处理为考虑了谐波源之间的相关性的随机变量。在此基础上，文中提出了一种有源和无源滤波器统一优化配置的机会约束规划模型，给出了用基于随机模拟的遗传算法进行求解的方法。模型以有源和无源滤波器总费用最小为目标，优化其安装地点及参数，并给出一18节点配电系统的算例。算例结果表明，考虑成随机过程后，能更好地合乎配电网的实际情况，使所需费用较小且能有效地抑制谐波。     

中央银行干预外汇交换市场的最优策略

现汇的交换率服从几何布朗运动。中央银行的目的是使交换率尽可能限制在一个给定区域。在交换率与给定目标之间有消费成本。另外，在每一次干预中，存在一个固定成本和比例成本。目的是找一个最优干预水平和规模，使得总成本最小。可以用随机脉冲控制来解决这一问题。     

Spatial indexing of high-dimensional data based on relative approximation

We propose a novel index structure, the A-tree (approximation tree), for similarity searches in high-dimensional data. The basic idea of the A-tree is the introduction of virtual bounding rectangles (VBRs) which contain and approximate MBRs or data objects. VBRs can be represented quite compactly and thus affect the tree configuration both quantitatively and qualitatively. First, since tree nodes can contain a large number of VBR entries, fanout becomes large, which increases search speed. More importantly, we have a free hand in arranging MBRs and VBRs in the tree nodes. Each A-tree node contains an MBR and its children VBRs. Therefore, by fetching an A-tree node, we can obtain information on the exact position of a parent MBR and the approximate position of its children. We have performed experiments using both synthetic and real data sets. For the real data sets, the A-tree outperforms the SR-tree and the VA-file in all dimensionalities up to 64 dimensions, which is the highest dimension in our experiments. Additionally, we propose a cost model for the A-tree. We verify the validity of the cost model for synthetic and real data sets. Edited by T. Sellis. Received: December 8, 2000 / Accepted: March 20, 2002 Published online: September 25, 2002     

Superconsistent Discretizations

We say that the approximation of a linear operator is superconsistent when the exact and the discrete operators coincide on a functional space whose dimension is bigger than the number of degrees of freedom needed in the construction of the discretization. By providing several examples, we show how to build up superconsistent schemes. Many open questions will be also rised and partially discussed.     

On Average Versus Discounted Reward Temporal-Difference Learning

We provide an analytical comparison between discounted and average reward temporal-difference (TD) learning with linearly parameterized approximations. We first consider the asymptotic behavior of the two algorithms. We show that as the discount factor approaches 1, the value function produced by discounted TD approaches the differential value function generated by average reward TD. We further argue that if the constant function—which is typically used as one of the basis functions in discounted TD—is appropriately scaled, the transient behaviors of the two algorithms are also similar. Our analysis suggests that the computational advantages of average reward TD that have been observed in some prior empirical work may have been caused by inappropriate basis function scaling rather than fundamental differences in problem formulations or algorithms.     

离轴全息的普遍表述

在旁轴近似下,将平面透明物体置于任何位置和选择任何取向,以及物光束与参考光束呈任意夹角的情况下,讨论了全息的记录和重建,给出了重建的Fresnel衍射的普遍关系式,也得到也得到了成像关系的一些特征。     

一类化学反应的振荡性

本文讨论化学反应A+B→2B,B→C中有逆反应时,其对应的数学模型,给出了存在唯一极限环的条件,并考虑了其何时产生强迫振荡。     

计算线路断相加短路故障的新方法

本文在常规的故障分析方法中引入补偿原理、迭加原理和互易定理，提出了一 种无需修改原网各序节点阻抗(或导纳)阵，快速计算互感或无互感线路断相 加短路故障的新方法。经实例计算表明，文中算法正确、有效。     

密集模态的判断准则

用特征向量转角给出了一种密集模态的判别准则。算例表明本文方法有效