增值业务助力电信运营商转型

分析了运营商当前面临的问题;提出通过开发新的业务满足人们通信、娱乐、学习、工作、生活的需要．改变人们的生活方式．即向综合信息服务提供商转变;探讨了如何从业务层面实现这一转变。     

Target Positioning Algorithm Based on RSS Fingerprints of SVM of Fuzzy Kernel Clustering

The positioning technology based on receive signal strength (RSS) fingerprints has become one of the hottest research spots with its advantages of simple deployment, low cost, and single parameter. However, in the limited space, the multipath and shadowing, result in poor separability of the fingerprint data, and low accuracy of target localization. In this paper, a novel RSS fingerprints positioning algorithm that is based on fuzzy kernel clustering SVM is proposed to combat the multipath and shadowing effects. The first step of the proposed positioning algorithm is to use kernel function to map the traditional fingerprints sample data to high-dimensional feature space to generate fuzzy classes. The second step is to generate binary-class SVM of fuzzy class based on the relationship between classes and internal discrete information of each class. After that, we can use the binary fuzzy class SVM to dichotomize the classified fingerprints in the first step, and combine these dichotomous SVMs into a handstand classification binary tree. And thus, the proposed positioning algorithm achieves quick and accurate positioning. Experimental results show that the positioning accuracy and locating stability of proposed positioning algorithm are improved by 38.73% and 59.26%, respectively, compared with the traditional RSS fingerprints algorithm.

     

各向异性海洋湍流对外差式DPSK无线光通信系统的性能研究

应用广义的惠更斯-菲涅耳原理及改进的Rytov方法,采用基于Gamma-Gamma光强概率分布的海洋湍流信道模型,得到了中断概率解析式.并在此基础上对各向异性海洋湍流高斯光束外差式差分相移键控(DPSK)调制的中断概率性能进行了研究.仿真分析了不同的各向异性海洋湍流下各种海洋湍流参数(温度与盐度波动对功率谱变化贡献之比...     

侧滑转弯反舰导弹末端机动的控制研究

反舰导弹进行末端机动,有利于增大突防概率.本文对反舰导弹的末端机动进行了分类,讨论了几种可能的控制实现方式的优缺点,给出了在几种控制指令下的末端机动实现公式,进行了具体的控制指令设计,并给出了一体化公式的一个例子.     

Research on topology control based on Voronoi diagram algorithm in FSO networks

Telecommunication Systems - In a wireless sensor network (WSN) where positioning information is not assumed or is partially available, efficient data access is a very challenging issue especially...     

An Investigation on the Coupled Thermal–Mechanical–Electrical Response of Automobile Thermoelectric Materials and Devices

Thermoelectric (TE) materials, which can directly convert heat to electrical energy, possess wide application potential for power generation from waste heat. As TE devices in vehicle exhaust power generation systems work in the long term in a service environment with coupled thermal–mechanical–electrical conditions, the reliability of their mechanical strength and conversion efficiency is an important issue for their commercial application. Based on semiconductor TE devices wih multiple p–n couples and the working environment of a vehicle exhaust power generation system, the service conditions of the TE devices are simulated by using the finite-element method. The working temperature on the hot side is set according to experimental measurements, and two cooling methods, i.e., an independent and shared water tank, are adopted on the cold side. The conversion efficiency and thermal stresses of the TE devices are calculated and discussed. Numerical results are obtained, and the mechanism of the influence on the conversion efficiency and mechanical properties of the TE materials is revealed, aiming to provide theoretical guidance for optimization of the design and commercial application of vehicle TE devices.     

基于正交试验的细菌觅食算法的全局最优化

细菌觅食算法在求解全局最优化问题时的性能大部分依赖于参数的设置,各参数的值不同,则细菌觅食算法的收敛速度和得到的最优解也不同。本文主要介绍了用正交试验的方法设置细菌觅食算法的参数来求解全局最优化的问题,通过正交试验方法来检测多组参数对细菌觅食算法效率的影响,用经典的测试函数数对这种组合方案进行检测对比,通过对实验结果数据分析可得出参数的最佳组合方案。最终实验结果表明用正交试验法设置的细菌觅食算法的参数组合方案可以提高算法的效率和收敛速度,使算法能够更快更好的得到测试函数的近似最优解。     

基于物联网的矿井温、湿度检测系统设计

为了实现对矿井温、湿度检测,提出了一种基于物联网的矿井温、湿度检测系统,并完成了系统的软硬件测试。硬件包括由分布在矿井中的测量节点组成的无线传感网络,由基站节点和监控终端设备相连接形成的监控装置,软件采用MSP430进行编程,并实现了温湿度信号检测。实际应用表明,该系统具有体积小,部署方便,成本低廉等优点。     

单相光伏并网逆变器无差拍控制的研究与仿真

光伏并网逆变器是光伏发电系统的主要部件,为了达到更好的效率输出更高质量的电能,对逆变器电流进行快速有效的控制尤为关键。该文简单介绍了当前光伏并网逆变器的几种常用控制方法及其基本思想,分析了并网逆变器的工作原理和无差拍控制方法的原理,给出了逆变器脉冲宽度的计算和参考电流的获取方法,通过MATLAB/Simulink软件仿真表明,无差拍控制在单相光伏并网逆变器控制中动态响应特性好,控制方便,电流跟踪电网电压波形好。