一种具可移动性的热电池动态性能测试系统

针对多种型号热电池动态性能测试的通用性和移动性要求,采用模块化结构,通过计算机实现测试过程的自动化。利用GPIB接口与计算机的通信,实现了计算机对程控直流电源、电子负载、WR1000热敏阵列记录仪的控制及数据的采集和自动储存,测试系统可以随意切换或裁剪设备以适应移动测试要求,使热电池动态性能测试系统具有高精度、多负载、通用性、可移动性和自动化的特点。     

动态链接库技术在IEEE488接口编程中的应用

为了提高现代测试效率和仪器的测试精度,实现硬件不具有的一些功能,可通过计算机对IEEE488接口仪器的操作和控制来实现.该方法采用Windows的DLL(动态链接库)技术,方便地把多台仪器组合起来,形成由计算机控制的自动测量系统.作者介绍了IEEE488接口的Windows程序设计的基本思想,并结合导弹热电池测控系统的设计,给出了用DLL技术实现对程控电子负载、程控电源和热电式阵列记录仪进行编程的方法.     

基于微型热敏传感器阵列的边界层分离点测量研究

通过分析流体边界层分离原理,针对分离点附近物面剪应力的变化规律,提出了用微型热敏传感器阵列在被测物体表面贴附完成实时分离点检测的测量方案.同时,提出了基于流体壁面剪应力分布测量边界层分离点原理的一维微型热敏传感器阵列输出信号的处理方法,并利用柔性一维热敏传感器阵列在标准翼型NACA0012上进行低速风洞试验,得到流体剪应力对应翼型表面位置传感器上的输出电压数据.通过对试验结果进行数据处理,验证了该判定方法对分离点位置判定的正确性和有效性.     

基于CAN总线的车辆液晶显示处理系统

文章介绍了车辆状态信息显示处理系统及cAN总线在现代客车上的应用。该系统是以AT89S52单片机 SJA1000CAN控制节点十SED1335液晶显示控制器为核心,并辅以扩展电路构成的汽车行驶记录仪。在研究、参考国内外现有行车记录仪的基础上,充分利用现代电子、计算机、传感测控等方面的技术成果,开发了新一代基于CAN总线的多功能行车记录仪。该系统不仅具有检测、超限报警等常规功能,而且具有点阵LCD中文显示功能．数据存储功能,以及控制功能。实现了更高的智能水平。     

C语言在AVR单片机控制的微打印开发与应用

在计算机高速测控的时代下,运用AVR单片机ATMEGA16做为主控制芯片,在芯片内建立打印字库,使用FAN8200做为热敏打印机走纸系统步进电机的驱动芯片,以日本精工LTP1245高速热敏打印机芯,用计算机控制程序对移位实现数据加载,在测量与控制模式下命令走纸步进电机所需的PWM驱动信号,并通过计算机设计了自定义的字符库,简化了硬件结构,降低了系统成本。通过本课题的研究,探索了单片机技术的最新发展方向以及AVR单片机对微型热敏打印机的控制方法,建立简单、实用、低成本的微型热敏打印系统并取行很好的应用价值。     

基于PIC单片机的温湿度记录仪设计

本文介绍了以PICl6F688型低功耗单片机为控制器的温湿度记录仪的设计与实现,采用数字式传感器对温湿度进行测量,并将所测量数据实时存入外部存储器EEPROM（24L C512）中。系统采用3V锂电池供电,采集数据间隙系统处于休眠状态,降低了系统能量消耗。开始记录数据之前,采用VB设计操作软件通过计算机串口对记录仪参数（记录时间和开启记录仪方式）进行设置,测量数据时可脱离上位机单独运行。该记录仪具有稳定可靠、体积小、量化误差小、响应速度快、便于携带和适用面广等特点。     

动态链接库技术在IEEE488接口编程中的应用

为了提高现代测试效率和仪器的测试精度,实现硬件不具有的一些功能,可通过计算机对IEEE488接口仪器的操作和控制来实现。该方法采用Windows的DLL(动态链接库)技术,方便地把多台仪器组合起来,形成由计算机控制的自动测量系统。作者介绍了IEEE488接口的Windows程序设计的基本思想,并结合导弹热电池测控系统的设计,给出了用DLL技术实现对程控电子负载、程控电源和热电式阵列记录仪进行编程的方法。     

基于AT89C5131的车辆行驶记录仪的硬件设计

描述了基于国家标准GB/T19056-2003,以AT89C5131为核心,配合以其他相关功能芯片的汽车行驶记录仪的硬件实现.对汽车行驶记录仪的工作原理、相关芯片的功能及使用方法、系统实现方法及设计思路进行了详细的介绍和分析.汽车记录仪的性能在实验室条件下进行了检测,并模拟了数据采集、数据记录、数据显示、数据传输、抗干扰、语音报警等功能,其具有高可靠性,高安全性及实用性等性能,证明了汽车行驶记录仪能够在各种复杂环境中使用.     

基于Flash的高速大容量固态存储系统设计

介绍一个高速大容量固态存储系统的组成机制和实现技术.特点是使用固态存储芯片Flash(闪存)阵列作为存储介质,采用多级流水线和并行总线技术存储高速数据.通过FPGA(现场可编程门阵列)产生控制时序和进行数据缓冲,成功实现了4×4片Flash阵列对30 MB/s高速数据的实时存储,并可通过扩展Flash阵列满足更高速度和更大容量的存储要求.系统通过USB2.0与计算机进行数据通信.     

低成本无人飞行器机载数据记录仪的设计与实现

针对无人飞行器机载数据记录仪的应用背景和使用要求,设计了一种新型、低成本的软硬件系统.根据飞行器的姿态数据、制导指令和执行机构等信号采集记录要求,提出了一种基于SOPC(system on a programmable chip)的数据记录仪总体设计结构.记录仪实现了系统脉冲启动和信号采集隔离等要求;采用固态电子硬盘作...     

Convergence analysis of the Neumann–Neumann waveform relaxation method for time-fractional RC circuits

The classical waveform relaxation (WR) methods rely on decoupling the large-scale ODEs system into small-scale subsystems and then solving these subsystems in a Jacobi or Gauss–Seidel pattern. However, in general it is hard to find a clever partition and for strongly coupled systems the classical WR methods usually converge slowly and non-uniformly. On the contrary, the WR methods of longitudinal type, such as the Robin-WR method and the Neumann–Neumann waveform relaxation (NN-WR) method, possess the advantages of simple partitioning procedure and uniform convergence rate. The Robin-WR method has been extensively studied in the past few years, while the NN-WR method is just proposed very recently and does not get much attention. It was shown in our previous work that the NN-WR method converges much faster than the Robin-WR method, provided the involved parameter, namely β, is chosen properly. In this paper, we perform a convergence analysis of the NN-WR method for time-fractional RC circuits, with special attention to the optimization of the parameter β. For time-fractional PDEs, this work corresponds to the study of the NN-WR method at the semi-discrete level. We present a detailed numerical test of this method, with respect to convergence rate, CPU time and asymptotic dependence on the problem/discretization parameters, in the case of two- and multi-subcircuits.     

Convergence and comparisons of waveform relaxation methods for initial value problems of linearODE systems

In this paper we investigate waveform relaxation (WR) methods for solving initial value problems of linearODE systems. Some sufficient conditions for convergence are proposed. A class ofWR AOR, WR SOR, andWR JOR methods is defined and their convergence is discussed. The asymptotic rates of convergence of two differentWR methods are compared.     

An optimum feature extraction method based on Wavelet–Radon Transform and Dynamic Neural Network for pavement distress classification

Quantification of pavement crack data is one of the most important criteria in determining optimum pavement maintenance strategies. Recently, multi-resolution analysis such as wavelet decompositions provides very good multi-resolution analytical tools for different scales of pavement analysis and distresses classification. This paper present an automatic diagnosis system for detecting and classification pavement crack distress based on Wavelet–Radon Transform (WR) and Dynamic Neural Network (DNN) threshold selection. The algorithm of the proposed system consists of a combination of feature extraction using WR and classification using the neural network technique. The proposed WR + DNN system performance is compared with static neural network (SNN). In test stage; proposed method was applied to the pavement images database to evaluate the system performance. The correct classification rate (CCR) of proposed system is over 99%. This research demonstrated that the WR + DNN method can be used efficiently for fast automatic pavement distress detection and classification. The details of the image processing technique and the characteristic of system are also described in this paper.     

Convergence conditions on waveform relaxation of general differential-algebraic equations

In the paper, we show some new convergence conditions on waveform relaxation (WR) for general differential-algebraic equations (DAEs). The main conclusion is that the convergence conditions on index r+1 can be derived from that of index r, in which the corresponding system is composed by ordinary differential equations if r=0. The approach of analysing relaxation process is novel for WR solutions of DAEs. It is also the first time to give the convergence conclusions for general index systems of DAEs in the WR field.     

BWR——带缓冲的虫孔路由技术

MPP互联网中通常使用虫孔路由WR（Wormhole Routing)交换技术来提高网络性能,采用该技术,每个结点所需的通信缓冲小;并且当消息长度远远大于微片长度时,消息的传输延迟时间与传输距离无关。但WR技术也具有容易阻塞和产生刹车问题的缺点。该文在WR技术的基础上,提出了带缓冲的虫孔路由BWR（Buffered Wormhole Routing)交换技术,并对采用BWR技术的k-ary n-mesh的消息平均传输延迟进行理论分析与模型模拟。结果均表明BWR技术可以较好地解决WR技术带来的问题,可以较好地提高网络的性能。     

真空热试验温度参考点热响应测试系统设计与实现

在航天器真空热试验的温度测量中应用最广泛的是热电偶测温系统,温度参考点是热电偶测温系统的重要组成部分,对温度测试数据的准确性和航天器产品的安全有很大影响。为了在热试验开机前对参考点铂电阻与热点偶补偿端匹配关系的正确性进行验证,设计了一种可用于真空热试验的热电偶测温参考点热响应测试系统。该系统由加热器以及控制箱组成,可通过LAN网络与上位控制计算机连接实现热响应远程测试。文章通过对参考点装置的热分析以及热响应测试原理分析,给出了系统的硬件结构以及软件设计方案,并在多项航天器真空热试验中投入使用,提高了航天器真空热试验热电偶测温系统的可靠性。     

A parareal algorithm based on waveform relaxation

We report a new parallel iterative algorithm for time-dependent differential equations by combining the known waveform relaxation (WR) technique with the classical parareal algorithm. The parallelism can be simultaneously exploited in both sub-systems by WR and time by parareal. We also provide a sharp estimation on errors for the new algorithm. The iterations of parareal and WR are balanced to optimize the performance of the algorithm. Furthermore, the parallel speedup and efficiency of the new approach are analyzed by comparing with the classical parareal algorithm and the WR technique, respectively. Numerical experiments are carried out to verify the effectiveness of the theoretic work.     

基于实时滤波的瓶盖密封性测试系统设计

为确保瓶盖的密封性,需要对瓶盖进行密封性抽样检测;在分析既往的机械式测试方法的基础上,设计了一种基于实时滤波的瓶盖密封性测试系统,包括系统的软硬件设计,整体综合测试;采用人机操作界面,使用方便,系统可以存储测量数据及测量结果,并能够实时将本次结果通过嵌入式热敏打印机打印出来;实验结果证明,该系统检测瓶盖密封性准确度达100%;目前该设计已经投入应用,通过应用表明该设计方法方便可靠。     

基于大数据分析的2×1000 MW火力发电机组不良数据识别方法研究

为了对2×1000 MW火力发电机组飽不良数据进行分析和识别,提出了电机组运行状态预测模型,以超短期电功率为预测对象,从不良数据的角度出发,建立了一个基于支持向量机(SVM)和随机马尔科夫链的数据分析识别模型。首先,基于大系统数据,利用SVM对电机组进行预测,得出误差和特征;然后,基于马尔科夫链原理,建立状态转移概率矩阵,修正SVM模型的结果;最后,对状态预测数据进行分类整理。对于2×1000 MW火力发电机组,实验结果表明,所提方法可以较准确地分析识别不良数据,准确率达到92%,为2×1000 MW火力发电机组提供良好的纠错环境。