BP-neural networks预测法在湛江港港口吞吐量预测中的应用

本文对港口吞吐量预测的方法进行了研究,分析了传统预测方法在实际应用中存在的问题,利用黑箱模型理论对湛江港近年吞吐量与建设投资额进行定性研究和定量检验,证明了港口吞吐量与建设投资额之间存在显著的正相关关系,并基于此提出基于BP-neural networks的预测方法,为湛江港港口吞吐量的预测提供了一种新的方法与途径。     

Application of fuzzy neural network to the nuclear power plant in process fault diagnosis

The fuzzy logic and neural networks are combined in this paper, setting up the fuzzy neural network (FNN) ; meanwhile, the distinct differences and connections between the fuzzy logic and neural network are compared. Furthermore, the algorithm and structure of the FNN are introduced. In order to diagnose the faults of nuclear power plant, the FNN is applied to the nuclear power plant, and the intelligence fault diagnostic system of the nuclear power plant is built based on the FNN . The fault symptoms and the possibility of the inverted U-tube break accident of steam generator are discussed. In order to test the system‘ s validity, the inverted U-tube break accident of steam generator is used as an example and many simulation experiments are performed. The test result shows that the FNN can identify the fault.     

银盘乌江电站工程GPS独立控制网的测布

结合乌江银盘水电站工程GPS控制网的布设,商用软件中PowerAdj应用,介绍了采用GPS布设高精度工程平面控制网受网形、观测值、解算软件的影响实施不同方案.分析了GPS基线粗差,并推介了采用PowerAdj解算GPS独立控制网的方法.     

A Model to Predict Rolling Force of Finishing Stands with RBF Neural Networks

In view of intrinsic imperfection of traditional models of rolling force, in order to improve the prediction accuracy of rolling force, a new method combining radial basis function（RBF） neural networks with traditional models to predict rolling force was proposed. The off-line simulation indicates that the predicted results are much more accurate than that with traditional models.     

A model to identify airport hubs and their importance to tourism in Brazil

Air transportation in Brazil has been recently liberalized and one of the consequences of this process is the concentration of flights in a few hubs. During the years 2006-2007 two fatal accidents created unprecedented chaos in both land and air sides of the system with harmful consequences to tourism in Brazil. The consequences were more airport congestion and many episodes of flight delays and cancellations that lasted for several months. We argue that, among other factors, this state of blackout was a result of the increase in the degree of concentration in few airports, particularly Congonhas (in São Paulo) and Brasília. Using data obtained from a survey with Brazilian experts, a comparison was made with two existing methods (the one used by the US Federal Aviation Administration and the usual Herfindahl-Hirschman method) in order to calculate the number of hubs in Brazil. Due to the huge discrepancy obtained between data from the survey and the other two methods considered, a new mathematical method based on the Herfindahl-Hirschman Index was proposed to identify the number of hubs in a given network. Drawing from the examples of what happened to tourist destinations during and after the air transport crisis in Brazil, the article concludes discussing the need for a more accurate tool to identify and to monitor the concentration of flights at the Brazilian air transportation network and its importance to tourism.     

城乡河网清漂设备发展

研究城乡河网漂浮物的组成,分析了它的产生给人类生活及环境所带来的危害,突出了清漂的必要性,详细介绍了目前我国的清漂技术和设备,针对城乡河网的特点指出清漂设备存在的不足,并提出了综合清漂设备的构思方案.     

A Study on Selecting the Shortest Routes by Voronoi Diagram in Route Networks of GIS

The problems of fast determining shortest paths through a polygonal subdivisionplanar with n vertices are considered in GIS. Distances are measured according to an Euclideanmetric. A geographical information system (GIS)has a collection of nearest neighborhoodoperations and this collection serves as a useful toolbox for spatial analysis. These operationsare undertaken through the Voronoi diagrams. This paper presents a novel algorithm thatconstructs a “shortest route set” with respect to a given source point and a target point byVoronoi diagrams. It will help to improve the efficiency of traditional algorithms, e. g. , Djkstraalgorithm, on selecting the shortest routes. Moreover, the novel algorithm can check theconnectivity in a complex network between the source point and target one.     

计算机网络优化设计研究

由于计算机技术的进步和通信网的快速发展,已使计算机网络链路容量需求的优势设计成为计算机网络设计中的关键问题,为此,提出了一种计算机网络链路容量设计方法,可求得整体最优解。本优化方法适用于集中式和分布式计算机网络的链路容量优化设计,最后给出了一个设计示例。     

轨道交通路网规划若干问题探讨

为使我国城市轨道交通路网规划从定性走向定量,同时作理论上的准备工作,应用系统分析和网络图论的方法对轨道交通网络规划的关键环节路网合理规模,路网形态,初级路网规划方法及软件数据流图逐一作了探讨,概括了路网规划的主题思想,对轨道交通规划的前期工作有指导意义。     

有源箝位双管正激变换器的分析及其仿真

提出了一种新型软开关变换器———有源箝位双管正激变换器。它通过在双管正激变换器的变压器原边并联一个有源箝位网络,以实现箝位、去磁和零电压开关等功能。给出了这种变换器电路的详细分析过程和仿真结果,并得出了一些重要结论。