一种基于KS距离的OFDM子载波数估计法

针对正交频分复用(OFDM)信号子载波数估计的问题,利用OFDM信号的高斯性,提出一种基于KS距离的子载波数估计法。侦收端DFT模块输出的KS距离在DFT点数与发射端匹配时最小。理论分析及仿真结果证明,该方法能区分高斯分布与非高斯分布,正确估计OFDM信号的子载波数。     

一种改进的基于粗糙集理论的特征选取方法

借鉴已有的特征选取方法和粗糙集相关理论,本文提出了一种改进的基于粗糙集理论的特征选择方法,其主要思想是通过构造粒度函数将其应用于特征在分类中的重要性度量和约简,最后通过实验验证了该方法是有效的,并能够显著降低文本特征维数,提高分类的效率和精度。     

SQL Server中OLE对象开发及应用

SQL Server内置的OLE扩展存储过程增强了SQL Server与外部系统的交互能力。实例给出了创建一个OLE对象的完整方法,并在SQL Server中创建基于OLE对象的自定义函数和调用该函数的完整过程。     

PowerBuilder中调用Windows API函数

简单描述了在PowerBuilder中调用Windows API函数的重要性。重点分析了PowerBuilder如何调用API函数,以及在调用过程中需要注意的事项。     

The next generation air transportation system: An approach to function allocation

A method for function allocation was developed and applied to the conflict detection and resolution problem in the next generation air transportation system. The method identifies key capabilities required of agents, automated or human, to achieve the goals of the system through state‐based modeling. For conflict detection and resolution in the next generation air transportation system, those capabilities include the ability to accurately identify current separation, predict future losses of separation and collisions, and identify four‐dimensional trajectory changes that, when implemented, will result in proper future separation. The modeling method feeds into an analysis of potential levels of automation across four stages of information processing, yielding a taxonomy of possible function allocation schemes, which can then be analyzed with respect to system and operator performance needs. The taxonomy is identified and analyzed for the current and future conflict detection and resolution system in air traffic control. © 2011 Wiley Periodicals, Inc.     

基于径向基神经网络的UPQC并联侧谐波电流预测与补偿

UPQC并联侧谐波电流补偿精度直接影响电网供电质量,传统指令电流信号提取ip-iq法存在低通滤波器及多种坐标变换算法,低频谐波无法被滤除且电流补偿存在一拍时滞.针对UPQC指令电流信号提取精度问题,提出径向基神经网络与ip-iq法结合的谐波电流提取方法,增加低频谐波提取环节,训练径向基神经网络拟合ip-iq法补偿过程中的时滞误差,生成谐波电流补偿模块,补偿ip-iq法谐波电流提取偏差.分别对传统ip-iq法和所提出的指令电流提取方案进行电流补偿效果分析,经过改进后,电网电流的谐波含量从ip-iq法的6.42％下降到4.25％,验证了所提出指令电流提取策略的有效性.     

Research on High Altitude Remote Sensing Building Segmentation Based on Improved U-Net Algorithm

Building extraction from high resolution remote sensing image is a key technology of digital city construction[14]. In order to solve the problems of low efficiency and low precision of traditional remote sensing image segmentation, an improved U-Net network structure is adopted in this paper. Firstly, in order to extract efficient building characteristic information, FPN structure was introduced to improve the ability of integrating multi-scale information in U-Net model; Secondly, to solve the problem that feature information weakens with the deepening of network depth, an efficient residual block network is introduced; Finally, In order to better distinguish the target area and background area in the image and improve the precision of building target edge detection, the cross entropy loss and Dice loss were linearly combined and weighted. Experimental results show that the algorithm can improve the image segmentation effect and improve the image accuracy by 18%.     

利用模糊逻辑系统实现函数逼近的仿真研究

针对不确定性非线性系统，基于Wang L X提出的模糊辨识器的设计原理,给出了基于模糊逻辑系统实现函数逼近的方法，该方法通过采用中心平均模糊消除器和隶属函数，实时地调整参数来实现未知函数、尤其是非线性函数的逼近。通过适宜选择初始参数可使模糊逻辑系统在任意精度上逼近真实系统。该文给出了实现函数逼近的具体算法、步骤和程序流程，并利用MATLAB语言编写了实现函数逼近的通用程序，在工程中可利用此通用程序实现对未知作用函数的近似估算，具有一定的工程实际使用价值。实例仿真取得了良好的效果。     

电力系统网络工作票的功能及实现

工作票是电力系统运行部门进行倒闸操作、安排检修的基础,本文探讨了以网络技术为平台,由传统的工作票手工填票模式转向实现信息共享的网络工作票管理模式,重点对其重要功能和应用中需注意的的几个关键问题进行了分析。     

逻辑模块LOGO!在铸轧机喷涂装置上的应用

在介绍了SIEMENS公司逻辑模块LOGO!的功能的特点的基础上，对LOGO！在铸轧机喷涂装置上的应用设计过程作了详尽说明。