造船龙门起重机大车纠偏控制系统的设计与应用

造船龙门起重机随着造船业的迅速发展也跟着快速发展起来。在大车行走过程中,由于龙门起重机的刚腿和柔腿之间的跨距较大,因此要求刚腿和柔腿的位移要始终保持一致,如果偏差过大则会造成大车偏斜运行等严重后果。本文结合软硬件的设计,详细介绍了大车纠偏控制系统从位置检测到位置闭环控制是如何实现大车的实时纠偏。     

副井提升系统安全回路及上位机优化改造

针对煤矿副井提升系统安全回路软硬件及上位机中存在的不足进行了优化改造,改进了过卷试验方式,将闸系统紧停信号引入安全回路,并将安全回路各节点状态信号引入RSView32人机界面,实时显示安全回路状态;根据现场检修需要,在上位机增加了复位显示功能及行程偏差大报警信号。实际应用表明,该优化改造可迅速定位故障节点,实现软硬件互查。     

Flight control of tethered kites in autonomous pumping cycles for airborne wind energy

Energy harvesting based on tethered kites benefits from exploiting higher wind speeds at higher altitudes. The setup considered in this paper is based on a pumping cycle. It generates energy by winching out at high tether forces, driving an electrical generator while flying crosswind. Then it winches in at a stationary neutral position, thus leaving a net amount of generated energy.The focus of this paper is put on the flight control design, which implements an accurate direction control towards target points and allows for a flight with an eight-down pattern. An extended overview on the control system approach, as well as details of each element of the flight controller, is presented. The control architecture is motivated by a simple, yet comprehensive model for the kite dynamics.In addition, winch strategies based on an optimization scheme are presented. In order to demonstrate the real world functionality of the presented algorithms, flight data from a fully automated pumping-cycle operation of a small-scale prototype are given. The setup is based on a 30 m² kite linked to a ground-based 50 kW electrical motor/generator by a single line.     

Real-time nonlinear MPC and MHE for a large-scale mechatronic application

Progress in optimization algorithms and in computational hardware made deployment of Nonlinear Model Predictive Control (NMPC) and Moving Horizon Estimation (MHE) possible to mechatronic applications. This paper aims to assess the computational performance of NMPC and MHE for rotational start-up of Airborne Wind Energy systems. The capabilities offered by an automatic code generation tool are experimentally verified on a real physical system, using a model comprising 27 states and 4 inputs at a sampling frequency of 25 Hz. The results show the feedback times less than 5 ms for the NMPC with more than 1500 variables.     

基于生理振动分析的手机用户身份识别

为保护手机用户的个人信息,对用户进行身份识别认证,提出一种生物识别方法。利用智能手机内置的传感器,采集人体的生理振动信息;通过对采集数据进行去重力等预处理,提取均值、方差、能量、峰度、偏度等特征指标,利用z‐score方法进行标准化处理;进行分类器设计,得出分类器的查准率、误检率等评价指标。分析60组不同用户的生理振动数据,分析结果表明,该分类器的查准率最高可达98?33％。     

山西省近50年风速变化及突变特征分析

利用线性拟合、M-K方法对山西省22个气象观测站1960—2010年的逐日风速资料进行了倾向、突变、逐年代变化等特征分析。研究表明,近50年来山西省平均风速存在明显的下降趋势,平均风速由20世纪60年代的2.16 m/s下降到21世纪初的1.86 m/s;不同时间段呈现不同的变化特征,1979—1989年风速出现显著下降,年均递减率达到0.046 m/s,变率远超出其他时段;对近50年山西省平均风速进行M-K检验后发现,在1982年出现明显的突变点。山西省四季平均风速均呈下降趋势,四季风速下降速率最快的为春季,冬季次之,夏季风速下降速率最慢。同样,四季风速均发生突变,突变时间点分布在1980—1985年间。除8月外,山西省各个月份风速也呈下降趋势,且均出现突变现象。     

基于模糊决策的风力发电产业评价研究

根据风力发电技术产业的特点,构建改进层次分析与模糊一致矩阵相结合的方案决策数学模型,该模型既可以减少确定判断矩阵的盲目性,又可以避开评价体系中各等级间的隶属度确定问题,使评价结果更加可靠,适合于信息尚不完整、受主观因素影响较强的评价。实例验证了这一模型的合理性、可行性和有效性,具有实用价值。     

改进型双馈风力发电机最大功率点跟踪策略

针对传统双馈风力发电机最大功率点跟踪极值搜索策略将正弦信号作为搜索信号而很难将正弦信号从总的输出信号中区分出来的问题,提出了一种利用风湍流作为极值搜索信号的改进型最大功率点跟踪策略。该改进策略对叠加风湍流的叶尖速比和功率系数进行傅里叶变换,获得相位差信息,从而确定叶尖速比变化方向,使双馈风力发电机达到最佳运行工作点。仿真结果表明,该改进策略可控制风力发电机转速较好地跟踪风速变化,实现了额定风速以下运行区域的最大风能捕获。     

新疆联通移动基站电源设计

首先,介绍了直流远供技术在移动基站的应用;其次,指出了风光互补供电系统在设计中需要改进的地方;最后,介绍了高效模块混插和联合接地分配箱等新产品的应用。研究表明,在通信工程设计中,不仅需要采用相适宜的新产品、新技术,还要定期对设计的工程进行回访,结合前期工程中存在的问题,对设计进行修正补充,使其更贴近实际情况。     

A single layer zero skew clock routing in X architecture

With its advantages in wirelength reduction and routing flexibility compared with conventional Manhattan routing, X architecture has been proposed and applied to modern IC design. As a critical part in high-performance integrated circuits, clock network design meets great challenges due to feature size decrease and clock frequency increase. In order to eliminate the delay and attenuation of clock signal introduced by the vias, and to make it more tolerant to process variations, in this paper, we propose an algorithm of a single layer zero skew clock routing in X architecture (called Planar-CRX). Our Planar-CRX method integrates the extended deferred-merge embedding algorithm (DME-X, which extends the DME algorithm to X architecture) with modified Ohtsuki’s line-search algorithm to minimize the total wirelength and the bends. Compared with planar clock routing in the Manhattan plane, our method achieves a reduction of 6.81% in total wirelength on average and gets the resultant clock tree with fewer bends. Experimental results also indicate that our solution can be comparable with previous non-planar zero skew clock routing algorithm. Supported in part by the National Natural Science Foundation of China (Grant No. 60876026), and the Specialized Research Fund for the Doctoral Program of Higher Education (Crant No. 200800030026)