Some Notes on the Formal Properties of Bidirectional Optimality Theory

In this paper, we discuss some formal properties of the model ofbidirectional Optimality Theory that was developed inBlutner (2000). We investigate the conditions under whichbidirectional optimization is a well-defined notion, and we give aconceptually simpler reformulation of Blutner's definition. In thesecond part of the paper, we show that bidirectional optimization can bemodeled by means of finite state techniques. There we rely heavily onthe related work of Frank and Satta (1998) about unidirectionaloptimization.     

基于正则化RBF神经网络的钢包精炼炉电极系统智能建模

通过RBF神经网络和模糊推理系统的比较，得出正则化RBF神经网络的输出特性，在此基础上利用改进的最近邻聚类算法确定网络的隐层节点个数和高斯函数中心，并估计输出层权值。仿真结果表明了所提方案的有效性。     

确定平面直线图完全单调链集的算法

本文提出求平面直线图完全单调链集的一种算法。基本思想是,先求平面直线图Ｇ的顶点集的凸壳及其直径,然后求各顶点在直径上垂直投影点,并按投影点的ｘ（或ｙ）坐 标排序Ｇ的顶点,最后按一定规则找出完全单调链集。     

网络社会秩序建设探析

互联网上新技术、新业务日新月异,它极大地方便了人们工作和生活的同时也出现了一些新情况、新问题,带来了一些负面影响,危及网络的安全、应用和发展。如何建立网络社会新秩序、有效规制网害,已成为亟待解决的社会问题。     

事件驱动型无线传感器网络MAC协议研究

提出一种应用于事件驱动型无线传感器网络的ED-MAC协议。该协议定义了网络的2种状态(常规态和事件态),为常规态的簇内数据采集和簇头汇报设计了不同的TDMA机制,事件态时采用预约机制对中继转发链路节点进行逐跳预约。实验结果表明:ED-MAC协议相比S-MAC协议具有能耗低、传输延时短的特点。     

nSPARQL: A navigational language for RDF

Navigational features have been largely recognized as fundamental for graph database query languages. This fact has motivated several authors to propose RDF query languages with navigational capabilities. In this paper, we propose the query language nSPARQL that uses nested regular expressions to navigate RDF data. We study some of the fundamental properties of nSPARQL and nested regular expressions concerning expressiveness and complexity of evaluation. Regarding expressiveness, we show that nSPARQL is expressive enough to answer queries considering the semantics of the RDFS vocabulary by directly traversing the input graph. We also show that nesting is necessary in nSPARQL to obtain this last result, and we study the expressiveness of the combination of nested regular expressions and SPARQL operators. Regarding complexity of evaluation, we prove that given an RDF graph G and a nested regular expression E, this problem can be solved in time O(|G||E|).     

A Kleene theorem for splitable signals

In this paper, we consider timed automata for piecewise constant signals and prove that they recognize exactly the languages denoted by signal regular expressions with intersection and renaming. The main differences from the usual timed automata are: time elapses on transitions (passing through a state is instantaneous), signals may be split on a run on an automaton and constraints on transitions correspond to unions of open intervals but should be satisfied on closed intervals. This makes exact rendez-vous impossible. The paper stresses on the similarities and differences from the usual model.     

集合体──制图教材改革的重大突破

直接运用点集的理论定义各种几何元素,提出采用不同的集合操作方法,改变点的集合状态,得到不同形状的集合体的新概念。通过分析贴合面边界的有效性,研究形体表面某些特殊线段的处理,阐迷了集合体的构形过程及画图的原则。     

多路线复杂约束下客机最佳航线的挖掘模型

在进行民航客机航线选取过程中,最优路线的选择受到天气、航空管制、航路冲突等因素的影响,应该路线选择的因素较为复杂,采用传统的方法进行航线选择,以单一影响因素指标相互独立为基础,通过设定特定权值作为选择的衡量标准,一旦航行线路影响因素发生波动,固定权值无法对其进行有效描述,航路选择中的挖掘结果无法达到最优.提出基于改进蚁群微正则退火算法的民航客机最佳航线挖掘模型.依据模糊综合评价理论,综合环境状态、航线状况及冲突情况多种因素对航线进行综合评价,计算航线权值,建立民航客机最佳航线的挖掘模型,获取初始路径搜索集合,利用双层循环结构理论,计算内外层循环结果,直至满足算法输出条件,实现民航客机最佳航线的挖掘.实验结果表明,利用改进算法进行民航客机最佳航线的挖掘,可以有效的提高航线选择的精度.