区域生长辅助的地图配准在室内定位中的应用

地图匹配（ MM）算法通过粒子滤波（ PF）利用室内地图信息来抑制基于惯性传感器的室内定位系统的误差累计。利用区域生长（ RG）算法结合当前步长和方向信息在地图上找到合理的落脚范围,并以此来判断粒子的有效性。这种方法能有效改善地图配准算法的实用性和计算复杂度。提出一种改进的零速度（ ZV）检测算法能准确提取步伐信息,间接提升了零速度更新（ ZUPT）算法和地图配准算法的精度。实验结果表明：该算法的定位误差小于1.0%,定位精度比单纯的航位推算（ DR）算法平均提高了5.97%。     

Finite‐time sliding mode observer for uncertain nonlinear systems based on a tunable algebraic solver

In this paper, a finite‐time sliding mode observer for nonlinear systems with unknown inputs is proposed. The observer is based on a method for the solution of time‐varying algebraic equations. This algebraic solver is shown to converge in finite time by means of Lyapunov analysis; furthermore, a way to tune it so that it converges after a user‐defined amount of time is presented. Through the use of this technique and sliding mode differentiators, the state variables and unknown inputs of a class of nonlinear systems, which do not need to be affine in the inputs, can be estimated without the explicit use of state transformations. Both the algebraic solver and the proposed observer are illustrated through simulation examples. Copyright © 2017 John Wiley & Sons, Ltd.     

On The Modeling of Twin Rotor MIMO System Using Chirp Inputs as Test Signals

This paper addresses the modeling problem for the twin rotor multi input multi output system. To develop experimental data, this popular commercial laboratory model of a helicopter from Feedback Instruments Ltd is excited with band limited chirp inputs. The conclusions drawn in this paper lead to four significant achievements: 1) derivation of a linear nominal model for Twin Rotor MIMO System, TRMS in short, from its equivalent nonlinear mathematical representation; 2) dynamic modeling of TRMS; 3) determination of non‐minimum phase dynamics; and 4) determination of linear operating region. The work considers systematic study of the system dynamics of TRMS and analytical treatment of its identified data leading to derivation of the RHP zero dynamics followed by pictorial illustrations indicating resonant modes associated with the plant. The method used in the present paper can be essentially used in modeling of 2 × 2 plants exhibiting non‐minimum phase dynamics and model uncertainties.     

基于工控机的驾驶员控制单元基本特性检测系统

本文介绍了一种基于工业控制计算机的驾驶员控制单元 (PCU)基本特性检测系统。分别介绍了该系统的总体结构 ,力传感器的选用、A/D采样电路的设计、控制器的设计 ,并给出了各部分的框图、电路原理图以及总体软件控制测试的流程图。该系统研究的方法可用于飞控系统PCU基本特性的检测设计 ,如改变被控对象 ,只需选用相应的传感器和控制器 ,即可实现该被控对象的检测目的。     

基于HVS彩色图像的扩展零树小波编码方法的研究

提出了一种基于视觉系统（HVS）特性和小波系数的扩展零树的彩色图像压缩编码方法。该算法按视觉重要性排序,产生一种嵌入式比特流。它不仅保留了EZW算法的高效、嵌入式编码的优点,而且获得了在低比特率下的彩色图像经压缩后的优良的复原图像效果。本算法同其他算法相比,在相同的压缩比条件下,恢复图像具有更好的视觉质量。     

Mathematical Morphology Based on Linear Combined Metric Spaces on Z2 (Part I): Fast Distance Transforms

Mathematical Morphology (MM) is a general method for image processing based on set theory. The two basic morphological operators are dilation and erosion. From these, several non linear filters have been developed usually with polynomial complexity, and this because the two basic operators depend strongly on the definition of the structural element. Most efforts to improve the algorithm's speed for each operator are based on structural element decomposition and/or efficient codification.A new framework and a theoretical basis toward the construction of fast morphological operators (of zero complexity) for an infinite (countable) family of regular metric spaces are presented in work. The framework is completely defined by the three axioms of metric. The theoretical basis here developed points out properties of some metric spaces and relationships between metric spaces in the same family, just in terms of the properties of the four basic metrics stated in this work. Concepts such as bounds, neighborhoods and contours are also related by the same framework.The presented results, are general in the sense that they cover the most commonly used metrics such as the chamfer, the city block and the chess board metrics. Generalizations and new results related with distances and distance transforms, which in turn are used to develop the morphologic operations in constant time, in contrast with the polynomial time algorithms are also given.     

石龙水电站扩容方案论证

石龙水电站是湖北省农村水电增效扩容改造试点之一,通过对该电站水轮发电机组运行现状进行分析,并结合目前国家电网对小水电的政策及要求,论证了其改造的必要性。其次通过计算分析,得出该电站目前没有额外增加装机容量的必要。同时石龙水电站也不具备通过增加电站引用流量或提高发电工作水头而实现扩容的条件,而应通过对电站的老旧机组及其附属设备等进行升级改造、对有压引水系统内表面进行清理及缺陷修补等,提高电能转换效率．从而达到增容的目的。     

膨润土负载纳米零价铁去除水中铅的研究

将纳米零价铁通过液态还原法负载于膨润土上,目的是为了比较负载对提高纳米零价铁去除重金属铅的能力的影响。从负载后扫描电镜图像中可以看出,负载后的纳米零价铁分散度更好。在相同投加量下,负载了纳米零价铁的膨润土对重金属铅的去除能力要远高于膨润土和纳米零价铁。铅的起始浓度为200mg／L,膨润土＋纳米零价铁的复合材料在0．4g／L的投加量下,去除率就达到90％以上。对材料的动力学研究结果则表明：纳米零价铁的反应速度较快,大部分的铅的去除都在1h以内完成。将吸附动力学实验结果进行一级和二级动力学反应拟合。二级拟和的线性相关系数明显高于一级。说明纳米零价铁和膨润土＋纳米零价铁复合材料与铅的反应更符合二级动力学反应假设。另外,纳米零价铁对铅的去除受到起始浓度的影响较大,而膨润土＋纳米零价铁则基本不受起始浓度的影响。     

高精度光纤陀螺组件标定方法

为了提高光纤陀螺组件的标定精度,从三轴惯导测试转台技术指标入手,根据惯导测试转台定位精度高的特点,设计了六位置静态分立式标定方案.通过设计一定的标定路径,利用地球转速和当地地理纬度,激励出陀螺的标度因数、安装误差和零位等12个参数,新的标定方案避免了标度因数和安装误差对零位的影响.对自研光纤陀螺捷联惯导系统在三轴惯导测试转台进行传统标定和六位置静态分立式标定,并将标定结果用于静态导航实验,多次实验结果表明,与采用传统标定结果的导航定位误差相比,采用六位置静态分立式标定结果的导航定位误差显著降低.     

脉冲频率调制LLC串联谐振X光机电源

为了满足X光机电源输出电压调节范围宽的要求,提出了一种全桥LLC串联谐振高频高压电源,并利用仿真软件设计其控制电路,使设计方法更加简单.主电路采用全桥LLC串联谐振、高压变压器、单相双向对称倍压整流电路,从理论上分析系统的工作原理,并建立了LLC谐振变换器的基波等效模型,对主电路的参数进行了设计;在控制电路设计中,借助仿真软件得到补偿前系统近似的开环传递函数,再进行控制器的设计.仿真结果表明,输出电压可以在40~120 kV范围内连续可调,输出电压上升时间短、纹波小,在输出电压跳变过程中,动态调节时间很短,证明了所提出的拓扑和控制电路设计方法的正确性和可靠性.