Downlink multiple access schemes for transmitted reference pulse cluster UWB systems

Transmitted reference pulse cluster (TRPC) signaling was recently proposed for low data rate ultra‐wideband communications. Compared with the conventional transmitted reference (TR), TRPC has a more compact and uniform spacing for the reference and data pulses and therefore solves the implementation problem posed by the long delay line requirement in the conventional TR. In this paper, downlink multiple access issue is further investigated for TRPC systems. According to the TRPC signaling structure, both code division multiple access (CDMA) and time division multiple access (TDMA) methods are discussed. Theoretical analysis and simulation results show that TDMA outperforms CDMA in both bit error rate performance and throughput. Copyright © 2010 John Wiley & Sons, Ltd.     

Optimal power system operation using parallel processing system and PSO algorithm

In recent studies, PSO algorithm is applied to solve OPF problem. However, population based optimization method requires higher computing time to find optimal point. This shortcoming is overcome by a straightforward parallelization of PSO algorithm. The developed parallel PSO algorithm is implemented on a PC-cluster system with 8 Intel Pentium IV 2 GHz processors. The proposed approach has been tested on the test systems. The results showed that computing time of parallelized PSO algorithm can be reduced by parallel processing without losing the quality of solution.     

智能电表家用负荷识别技术综述

智能电表是智能电网发展的基础,负荷识别是智能电表的重要功能之一。简单介绍了在家用负荷识别中的负荷特征,阐述了目前比较常用的几种非侵入式负荷识别方法,分析了各种负荷识别方法的优缺点,讨论了负荷识别技术研究的意义以及在实际应用中面临的问题。     

An Improved Method for Load Taxonomy Using Sample Shifting Technique and Signature Analysis

This paper illustrates an improved method of classification of electrical appliances, particularly for domestic loads, to construct load taxonomy on the basis of their signature analysis. Each electrical load is characterized by its own distinct signature and hence load signature analysis is useful in monitoring the health of the equipment, power quality, in determining individual energy usage etc. type of services. On the other hand, load taxonomy classifies these loads in several clusters on the basis of some features extracted from their signatures. In traditional methods of construction of load taxonomy, different signature patterns based on power metrics, V-I trajectories, Eigen vectors, etc. In this proposed method, with the adoption of sample shifting technique the required number of feature extraction is reduced to a lower value to find out various signature patterns than those are required in traditional load taxonomies. Moreover, a better taxonomy, having well separated groups of loads is achieved with lower number of extracted features.     

关于500kV紧凑型线路架线施工中的技术问题

阐述了500 kV罗平至百色紧凑型线路工程施工和监理过程中,电气距离控制、滑车安装、导线缠绕打绞、弧垂施工、相间间隔棒安装、金具更换等技术问题及采取的有效控制措施和处理方法.     

基于几何特征的飞机部位识别跟踪算法

针对复杂天气情况下形状可辨的飞机,提出了一种对飞机部位的识别跟踪算法。该算法利用飞机的几何特征,通过数学形态学的原理,在存有噪声干扰的运动图像中简单快速有效地识别出所需目标的重要部位,自动获取其跟踪模板,通过相关匹配技术实现对飞机重要部位的稳定跟踪。给出了应用该算法的具体步骤,并通过实验证明了该算法的有效性。     

馈源阵面排列对偏置多波束天线特性的影响

以３７单元馈源阵为例,就用于卫星移动通信系统中的偏置多波束天线进行分析探讨：在原有两种馈源阵阵面排列形式的基础上,又提出了第三种排列形式,即馈源阵的球面排列形式,并对这三种形式下偏置多波束天线的远场特征进行了计算比较,得出了一些有益的结论;另外,将馈源阵阵面适当地偏离焦点也可使多波束天线的远场特性得以改善。     

基于四粒子团簇态的可控量子隐形传态

提出利用四粒子团簇态传送一个未知单粒子态从而实现可控量子隐形传态的方案,发送者对她自己拥有的两个粒子做一次Bell基联合测量,两控制者合作对其两粒子进行Bell基联合测量,接收者在两个控制者的帮助下对其自己的粒子做相应的幺正变换,即可得到要传送的单粒子态,完成可控量子隐形传态.     

基于Docker容器技术的Linux在线实验环境设计

基于Docker容器的虚拟技术在云计算、大数据环境中被大规模的使用,针对Linux操作系统实验环境使用受限的问题,设计了基于Docker容器技术的在线实验环境,描述了实验环境构建的大致过程,对服务器端Docker容器的创建方法进行了分类分析和服务器压力测试,结果表明,所设计的Linux在线实验环境能够满足线上及线下教学...     

IP视频宽带服务器集群结构及实现

随着宽带网络的建设，IP视频应用的逐步普及，现有的基于集中控制／传输模式的服务器将成为系统的瓶颈。本分析了传统视频数据传输方式的不足，提出了利用Linux的Iptables建立分布式服务器集群模式，及采用渐进传输和动态缓冲区等技术改进视频数据传输的具体方案。从改进服务器体系结构和视频数据传输两方面人手，解决IP视频服务器的瓶颈问题。