ARM Cortex-M3处理器故障的分析与处理

本文介绍了ARM Cortex-M3处理器的4种故障:总线故障、用法故障、内存管理故障和硬故障。分析了这些故障产生的原因,叙述了如何通过故障状态寄存器找出故障原因,如何在程序开发阶段尽可能的避免故障的产生,以及故障的处理方法。     

基于JAVA的软件故障自动检测系统设计

为了提高软件的故障自动检测能力,进行软件故障自动检测系统优化设计,提出基于JAVA的软件故障自动检测系统。系统由软件故障数据采集模块、故障信息融合模块、特征提取模块、信息集成处理模块和故障专家系统诊断模块组成。在DSP和逻辑PLC中进行故障检测系统的集成开发。采用数据融合滤波技术进行软件故障信息的多传感器采集,对采集的故障采用自适应功率放大进行信息增强处理,提高故障的类别属性诊断能力,在故障信息融合中进行故障特征挖掘,提取反映软件故障类别的关联特征量,在专家系统进行故障识别和智能诊断。在JAVA开发工具下进行软件故障自动检测系统的模块化开发设计。测试结果表明,设计的软件故障检测系统具有很好的故障诊断能力,故障检测的准确率较高。     

基于阻抗计算的电缆早期故障定位方法

早期故障是永久性故障的前兆现象,对早期故障的定位可以有效防止永久性故障,减少故障带来的损失。本文利用Mary电弧模型模拟早期故障,通过故障电压的马鞍形故障特征提出早期定位算法,由故障电压和中性点电流值计算出故障点。最后通过PSCAD/EMTDC建立10kV单芯电缆模型,对早期故障定位进行仿真验证,验证了算法的可靠性。     

EoC故障的解决方法

在实际应用过程中,我们发现EoC的故障主要分为5部分,即设备故障、线路故障、用户端故障、外部供电故障、干扰故障。下面根据实践介绍这5部分故障的解决方法。1设备故障这部分故障主要是头端设备故障和终端设备故障。头端或者终端应该能够从网管处发现问题。例如三原五号信箱刚加上头端时丢包严重,技术人员通过厂家提供的测试软件登录上去,很快确定是头端设备出现问题。2线路故障这部分故障最多也是最麻烦的。线路不断出现问题,一定是没有严格按照规范施工。     

基于PSPICE进行模拟电路故障建模的方法

文章研究了基于PSPICE的模拟电路故障仿真中的故障建模问题。提出了用故障字典法诊断模拟电路硬故障时,基本元件的物理故障和集成电路的功能故障进行故障建模的方法。在直流诊断和交流诊断中，故障建模的方法有所不同。最后用例子说明了这种方法的可行性。     

全固态电视发射机功率合成器故障现象和分析

本文介绍了全固态电视发射机功率合成器故障的现象和处理过程,供大家参考和借鉴。功率合成器故障是非常见故障,介绍该故障的文章很少;同时,合成器故障具有信号通路故障的典型性。了解该故障现象,对处理这一类故障会有很大帮助。     

联合收割机远程监测故障数据库设计

目前多数联合收割机故障监测系统上不具备故障数据库,文中设计研发一套基于LabVIEW的联合收割机的远程故障监测系统并带有故障数据库。通过ARM进行数据采集,通过外接多种传感器,可实现对收割机前进速度,滚筒转速等的实时状态监测,通过数据存储,显示及分析,判断故障位置,进而实现远程故障诊断。系统添加故障库功能,可进行故障补救措施查询及新故障添加,对收割机故障进行提前预防和快速的事后处理。     

含光伏系统的微网并入配电网的故障区段定位研究

为解决传统配电网继电保护故障定位系统难以应对含光伏系统的微网并网运行的问题,提出了一种集中与分布式相结合的故障区域检测与隔离的保护方法。根据配电网的拓扑结构和假定的网络功率流向形成网络描述矩阵,在配电系统发生短路故障时,根据被保护线路故障的电压、电流分量的相位关系确定故障正方向,并形成故障信息矩阵。以故障信息矩阵对网络描述矩阵进行修正而形成故障判断矩阵,利用故障定位判据逐一查询故障判断矩阵即可快速准确地定位出故障位置,从而发出跳闸命令切除故障。     

变频器的常见故障

本文主要介绍变频器在使用过程中出现的短路保护故障、过流过载故障及其它故障,通过分析故障现象,确定各种故障原因,最终提供预防故障和维修变频器的方案。     

故障电流限制器中故障传感器的改进设计与实现

故障电流限制器电流迅速提升,会产生短路问题,需要通过故障传感器检测电流限制器中的短路故障,确保故障电流限制器的顺利运行。设计并实现故障电流限制器中的故障传感器,给出故障信号采集模块设计过程,通过引进LM293差分比较器的整形电路进行整形,再传递到MSC1210单片机进行变换,并通过故障诊断模块进行分析,将分析结果反馈到上位机中,对电流限制器的故障进行处理。给出了软件设计过程。实验结果表明,所设计的传感器可及时获取反映故障电流限制器的故障信息信号,故障信号采集效率和空间性能都较高。     

Enhanced Resource Blocks Management in D2D based Communication for 5G Networks

D2D based communication holds a promising future for 5G networks as they are efficient and can yield high data rates, good signal to noise interference ratio, improved resource-block uploading time, minimized delay from one end to the other and conserved power for transmission. The traditional system of cellular type contains cell edge clients who need a larger resource blocks count as well as time to upload data. Hence the quality of service will be reduced. The relay scheme in the proposal for cooperative type D2D networks is pivoted on the value of channel gain as well as transmission link distance. For bringing down the resource blocks’ count as well as uploading time, the paper is proposing a capable scheme of selection of relays that employs communication of D2D in the situations of uplinking. To begin with, in a cell modeling is done. It contains D2D pairs of multiple types as well as cellular clients. Next, the analysis related to issues of allocating resources as well as control of power is done. In order to lessen the resource blocks as well as their uploading time, the paper in proposal suggests a better blocks management mechanism that uses D2D based communication. Simulated output infers that the method in the proposal is superior to the present methods as far as time to upload contents; resource blocks, SINR, throughput as well as rates of data and Energy Consumption are concerned. Added to that, the stated method conserves 43% of the Energy Consumption of the network clients and while doing that the time to upload the contents is not affected.

     

基于不经意传输的拓扑隐藏广播协议设

为了保护消息广播中节点关系、地理位置等敏感信息,将高效的NTRU(Number Theory Re―search Unit)公钥加密算法与不经意传输协议相结合,通过引入不可信的第三方以保证广播的中间过程无法被任意节点所获知,从而实现了隐藏网络拓扑结构的目标.该协议可认为是拓扑隐藏广播的具体实现,解决了现有概念性方案中尚未涉及的秘钥重构、相邻节点身份隐藏及网络动态变化等问题.安全性分析表明,在半诚实攻击模型下该方案能够保证网络中任何一部分节点被攻破均不会导致其他节点拓扑信息泄露.此外,通过与相关概念性协议进行实验对比分析,该方案除安全性外还可充分体现计算、通信开销与节点平均度数无关的优势.     

10-GHz ultralow-noise optical sampling stream from a semiconductordiode ring laser

We report, what is to our knowledge, the lowest-noise pulsetrain produced to date with an actively mode-locked external-cavity semiconductor diode laser. Operating characteristics at 10 GHz include dispersion-compensated pulsewidths as short as 1.2 ps, amplitude noise as low as 0.12% rms, and residual phase noise as low as 43-fs rms. Potential application of such a laser in a next-generation optical analog-to-digital converter would theoretically provide as much as 8.6 bits of resolution, while sampling a 5-GHz waveform at the Nyquist frequency     

Optical properties of AlGaAs/GaAs nipi superlattices and theirapplication in asymmetric cavity spatial light modulators

Homo-nipi and hetero-nipi superlattices incorporated into asymmetric Fabry-Perot cavity structures are compared and evaluated for possible use as bit plane optical memory elements in terms of the magnitude of their optical nonlinearities, on-off contrast ratio, insertion loss, carrier lifetimes, and power required to change the state of the structure. Changes in superlattice absorption coefficient as high as 1500 cm^-1 and 1300 cm^-1 have been achieved in type I and type II AlGaAs/GaAs hetero-nipi structures, respectively. When normalized to the GaAs quantum well layer thicknesses, the change in absorption coefficient in the type I superlattice was as high as 12000 cm^-1. In asymmetric cavity modulator structures, on-off reflection contrast ratios as high as 60:1, carrier lifetimes as long as 4 ms, and on-state reflectivities as high as 0.62 have been observed. A 54:1 contrast ratio and an insertion loss of 8.5 dB were achieved simultaneously in a planar Fabry-Perot cavity structure excited with a pump beam power of 3.8 mW. The effective carrier lifetime in this case was 25 μs     

桐乡市广电IP城域网系统配置优化探析

以CISCO系列交换设备组网为例,着重从生成树优化、OSPF路由优化、系统管理VLAN设置、网络时间校准以及设备配置标准模板等方面,简述了中小型广电IP城域网系统配置的优化思路以及几个参考实例。     

基于FPGA的并行数据转SPI接口设计

在进行不同设备间的数据传输时,最基本的要求是连线尽可能少、数据传输速率尽可能快、误码率尽可能低。对此进行了并行数据转换为串行数据的接口电路研究,提出了同步并行传输速率的n倍改进SPI传输方案。其特点是传输速率高、时钟独立、可与并行接口端和SPI串行接口端进行双向通信。测试结果显示系统达到预定功能,其接口电路的实现方法可为数据的高速接口提供新的借鉴。     

建筑外窗保温性能检测装置测控系统的设计与实现

以建筑节能为目的,介绍了一种建筑外窗保温性能检测装置测控系统的设计与实现。依照现场总线的技术要求,系统硬件采用通用微型计算机为主机,各种测控仪表为从机,双绞线为传输介质,按照RS-232／RS-485串行总线标准及接口技术实现主从机之间的信息交换。讨论了在Visual C＋＋开发平台下,利用串口类CSerialPort实现多串口通信,以及多线程、数据库、打印等功能的实现。实现了根据国家标准GB／T8484-2002的要求完成的测控功能。     

Vertical cavity surface-emitting semiconductor laser with CWinjection laser pumping

Room-temperature CW operation of a GaAs/AlGaAs vertical cavity surface-emitting laser with a resonant periodic gain medium, using a GaAs/AlGaAs diode laser array as a pump source, is discussed. Pumping thresholds as low as 11 mW at 730 nm, output powers as high as 10 mW at 856 nm, and external quantum efficiencies as high as 70% are obtained, with considerably improved temporal and spatial coherence properties compared to the pump laser. This is the first reported operation of such a laser with an efficient, compact pump source, demonstrating its suitability for efficient integration     

HCMS-2903数字显示器及应用系统设计

HCMS-2903是一种高性能、易于使用的CMOS数字字符点阵显示的发光二极管显示器(LED)芯片.文中在简要介绍HCMS-2903结构特点、通信协议的基础上,介绍了利用HCMS-2903作为显示器、单片机AT89C52作为控制器、计算机作为数据源而实现数字画面的显示、切换和控制的原理,以及硬件结构和软件设计等.该设计已被用于工程实践,获得了满意的效果.     

A fast 7.5 ns access 1K-bit RAM for cache-memory systems

A 1024-bit ECL RAM with greatly improved speed performances was developed. Typical access time and write cycle time are as short as 7.5 and 10 ns, respectively, under 784 mW of power dissipation, achieving a power and access-time product as small as 5.7 pJ/bit. Novel ECL circuit techniques, especially in address decoder circuits, as well as improved process technologies enabled realizing these high-speed characteristics. The device uses a V-groove isolation process and a shallow emitter diffusion technology with doped polysilicon. It has a memory organization of 256-words by 4-bits where its main use is as a cache memory. Besides this basic organization, it has flexibility to also operate as a 512-word by 2-bit and 1024-word by 1-bit memory.