双通道无刷直流控制系统的可靠性分析

余度结构常常被使用于提高飞机电气系统的可靠性，一种应用于多电飞机(MEA)机电作动系统(EMA)的无刷直流调速系统采用了双通道结构。本文采用可靠性预计方法分析了该系统的可靠性，讨论了系统的可靠性预计方法，并进行了可靠性计算，论证了双通道结构的合理性。     

计算机在电子学方面的应用

TP39 02031870航电系统5 Cl互连的可靠性模型研究/周强,罗志强,李峭,熊华钢(北京航空航天大学)11北京航空航天大学学报一2001,27(5).一536一539研究未来航电系统关键协议一5 CI(可扩展的一致性接口)的可靠性建模问题.从5 Cl互连的基本模型出发,提出了基于任务的系统可靠性分析方法,建立了系统的可靠性模型,并针对航电系统中5 Cl的蝶型互连进行了可靠性分析,指明该方法在航电系统设计阶段对于任务划分和拓扑选择都将起到指导作用.图2表5参5(木)TP3902031871147基于虚拟仪器网络化旋转机械状态监测系统设计/陈迈涛,王友剑(浙江大学)11电子…     

中国电子学会可靠性分会第十三届学术年会论文选

目录1.装备产品研制的可靠性管理体系探讨!!!!!!!!!!杨光等(1)2.电子战可靠性信息管理平台展望!!!!!!!!!!!!龚懿等(5)3.产品可靠性与故障分析!!!!!!!!!!!!!!!!!邓林(10)4.产品可靠性与故障分析!!!!!!!!!!!!!!!!!王步冉(15)5.再议舰船装备可靠性!!!!!!!!!!!!!!!!!!施建荣(20)6.基于网络的故障信息管理系统!!!!!!!!!!!!!!赵之才(23)7.提高混合集成生产过程一次送检合格率质量管理方法!!!贺钲等(28)8.某高速数据解调终端分系统的可靠性定量设计!!!!!!戴柏林等(41)9.舰船电子设备可靠性设计!!!!!!!!!!!!!!!刘山金等(48)10.引信系统保险环节的可…     

电力调度交换系统的安全性管理

本文通过对RAMS(可靠性、可用性、可维护性和安全性)基本原理的阐述,提出了电力调度电话交换系统的安全性管理课题,对与系统安全性关联密切的设备固有可靠性和运行可靠性的定义和一般计算方法进行了说明,对安全性管理的重要工具—风险矩阵的定义和应用进行了概要描述。     

中科芯(58所)第一届检测技术研讨会征文通知

<正>中科芯(58所)第一届检测技术研讨会拟定于2017年6月下旬在江苏无锡召开,特向广大检测工作者征集论文。征文内容如下:1)宇航集成电路可靠性检测评价方法;2)军用高密度封装集成电路的可靠性评价方法;3)微系统组建(板卡、模块、KGD)可靠性验证方法;     

可靠性设计、试验与设备

0622589发电系统可靠性指标及其计算[刊,中]/陈可科//南京师范大学学报(工程技术版)．—2006,6(2)．—13-17 (L)发电系统传统地从概率、期望值、频率和持续时间几个指标衡量发电系统的可靠性,即电源充裕度。对发电系统传统可靠性指标及其计算方法进行了分析,并以IEEE-24RTS系统为例进行计算,分析影响和改善系统可靠性的因素,以期通过对传统指标和计算方法的剖析,为市场环境下可靠性问题分析提供依据。分析结果表明：可通过采用峰谷分时电价政策或进行合理有效的负荷管理,改变系统的负荷曲线形状,以期达到提高系统可靠性和经济运行的目的。参8     

一种基于红外热成像技术的星载EPC可靠性状态检测方案研究

该文针对星载EPC(Electronic Power Conditioner)可靠性状态检测问题引入了一种非接触式的红外热成像检测方法,介绍了应用该方法进行可靠性状态检测的理论依据及其检测系统构成;并在应用该系统对星载EPC样机进行了大量试验研究的基础上,依据数理统计理论和欧氏距离判别方法,首次提出了一个有效的基于红外热成像技术的PCB(Printed Circuit Board)可靠性状态检测数学模型。     

可靠性增长评估

目前用来评估可靠性增长的数学模型很多,但在国际国内标准中推荐的评估方法主要是杜安法和AMSAA法.杜安法是J.T.Duane于1962年提出的,它能以图示的方式给出所度量的可靠性参数发生的变化,也能得出可靠性参数的数字估计.AM-SAA方法是美国陆军器材设备分析机构提出的,它属于一种解析模型,它可以通过试验数据对产品的MTBF或故障强度λ的当前值和预计值求出区间估计,这种模型既可以用于连续型(以时间计)的可靠性系统,也可用于离散型(以周期数、英里数计)的可靠性系统、单系统或多重系统,以及那些时间截尾或失效截尾的试验.     

基于CPLD的可编程数字频率计的设计

采用美国Lattice公司生产的在系统可编程 (ISP)大规模集成逻辑器件 (CPLD)ispLSI 10 32E芯片实现可编程数字频率计的设计 ,其设计方法简便、高效、无风险 ,且能提高系统的可靠性及灵活性。     

综合业务数字通信系统与通信网

0632779支持IPv4／v6的移动VPN解决方案[刊,中]／薛海波／／信息安全与通信保密．-2006,(9)．-108-110(L) 0632780 No．7信令网络的维护和管理[刊,中]／胡文江／／信息安全与通信保密．-2006,(9)．-62-64(L) 0632781基于SDH传输平台现场数据的可靠性评价[刊,中]／张业鹏／／湖南科技大学学报(自然科学版)．-2006,21 (3)．-52-56(C)为提高SDH传输平台工作的可靠性,找出SDH传输平台系统在工作中的薄弱环节,实行系统的可靠性增长。在介绍某行业应用的SDH传输平台的结构与组成的基础上,从实际使用现场收集了4批可靠性数据,为掌握平台系统的可靠性水平,对失效数据利用统计方法进行了分类和分析,并利用可靠性相关理论计算了SDH传输平台系统的可靠性指标,找出了SDH传输平台系统的薄弱环节,为改进设计提供了依据。参8 0632782下一代高速两跳综合网络研究[刊,中]／刘传清／／信阳师范学院学报(自然科学版)．-2006,19(4)．-486-     

Enhancement of noise-suppressed speech by spectral processing implemented in a digital signal processor

This paper presents a noisy suppressed speech enhancement method by combining the basic spectral subtraction technique and spectral processing in the frequency domain to provide better noise suppression as well as better enhancement in the speech regions. In contrast to several previous approaches we do not try to achieve a complete removal of the noise, but instead our goal is to preserve a pre-defined amount of the original noise in the processed signal. This is accomplished by exploiting the masking properties of the human auditory system. The proposed algorithm is named PM “Proposed Method” which simulates properties of the human auditory system and applies it to the speech recognition system to enhance its robustness. The performance of the speech enhancement algorithm using the proposed masking model was compared with three other speech enhancement methods over 4 different noise types and five SNRs. The performances of the proposed approach are objectively and subjectively compared to the conventional approaches to highlight the aforementioned improvement. In this paper we discuss the design and development of a digital signal processor (DSP) implementation to achieve real-time performance of our filter. The target processor is a Texas Instruments TMS320C6713 floating point DSP.     

A human visual system-driven image segmentation algorithm

This paper presents a novel image segmentation algorithm driven by human visual system (HVS) properties. Segmentation quality metrics, based on perceptual properties of HVS with respect to segmentation, are integrated into an energy function. The energy function encodes the HVS properties from both region-based and boundary-based perspectives, where the just-noticeable difference (JND) model is employed when calculating the difference between the image contents. Extensive experiments are carried out to compare the performances of three variations of the presented algorithm and several representative segmentation and clustering algorithms available in the literature. The results show superior performance of our approach.     

双多进制正交扩频系统的比特软值输出算法

该文针对双多进制正交扩频与Turbo码的联合系统,基于最大后验概率(MAP)准则,提出了双多进制正交扩频输出比特软值的MAP算法,并给出了简化MAP算法;同时,对算法的定点和浮点性能进行了仿真,且与现有的软值算法进行了比较。结果表明,MAP算法能使整个系统获得相当的增益,L=3 的简化MAP算法在基本不增加复杂度情况下好于现有的双最大值算法约0.4dB。     

一种基于粒子群算法的多目标子阵划分优化方法

为了降低硬件成本和系统的复杂度,子阵划分对于大型的相控阵雷达来说是必要的。传统的子阵划分方法主要针对信号处理的单一性能指标优化。针对多项指标优化的问题,本文提出了一种基于粒子群算法的子阵划分结构优化算法,相对于传统的方法能够同时优化多项性能指标,提高信号处理的性能。通过对线性阵列的划分做仿真,展示了粒子群算法对子阵级波束形成多项性能指标的提高。      

TD-SCDMA系统的外环功率控制算法研究

在3GPP协议规范中对外环功率控制算法没有定义,由各设备生产和制造商决定。TD-SCDMA系统每时隙下服务用户数较WCDMA系统每帧下服务用户数明显减少;另外,采用了自适应的智能天线技术,适合WCDMA的外环功率控制算法不能直接适用于TD-SCDMA,提出了一种先进的自适应功率调整步长的外环功率控制算法。由于外环功率控制参数对系统性能影响较大,基于自适应智能天线技术,给出了不同参数下外环功率控制算法的性能,可用于TD-SCDMA网络的规划优化。     

Robust Adaptive Beamforming Under Quadratic Constraint with Recursive Method Implementation

When adaptive arrays are applied to practical problems, the performances of the conventional adaptive beamforming algorithms are known to degrade substantially in the presence of even slight mismatches between the actual and presumed array responses to the desired signal. Similar types of performance degradation can occur because of data nonstationarity and small training sample size, when the signal steering vector is known exactly. In this paper, to account for mismatches, we propose robust adaptive beamforming algorithm for implementing a quadratic inequality constraint with recursive method updating, which is based on explicit modeling of uncertainties in the desired signal array response and data covariance matrix. We show that the proposed algorithm belongs to the class of diagonal loading approaches, but diagonal loading terms can be precisely calculated based on the given level of uncertainties in the signal array response and data covariance matrix. The variable diagonal loading term is added at each recursive step, which leads to a simpler closed-form algorithm. Our proposed robust recursive algorithm improves the overall robustness against the signal steering vector mismatches and small training sample size, enhances the array system performance under random perturbations in sensor parameters and makes the mean output array SINR consistently close to the optimal one. Moreover, the proposed robust adaptive beamforming can be efficiently computed at a low complexity cost compared with the conventional adaptive beamforming algorithms. Computer simulation results demonstrate excellent performance of our proposed algorithm as compared with the existing adaptive beamforming algorithms.     

OFDM系统中自适应比特分配算法的研究

在研究OFDM系统和自适应分配技术的基础上,对几种重要的自适应分配算法进行详细分析,并通过仿真比较了它们的性能和复杂度.仿真结果表明,使用自适应分配算法的OFDM系统可以减小发射功率,提高系统性能.     

一种改进的信噪比估计算法

基于现今越来越多的算法需要信噪比的先验知识来进行性能优化,论述了信噪比估计在通信系统中具有的重要作用,介绍了信噪比估计算法的信号模型。通过分析现有的几种信噪比估计算法在较大的信噪比范围内的估计性能,提出了改进的信噪比估计算法,并对新算法的估计均值、估计偏差和估计方差进行了仿真。仿真及分析结果表明,改进的算法在较大的信噪比范围内性能良好,估计准确。     

基于Kalman滤波的盲多用户检测算法

盲多用户检测技术是第三代移动通信的关键技术,本文仿真分析了DS-CDMA通信系统中盲多用户检测的Kalman滤波算法的性能.并且将子空间算法和Kalman滤波算法进行结合,使得盲多用户检测的Kalman滤波算法的计算量大大降低.     

Iterative correction of phase noise and nonlinear distortion in orthogonal frequency division multiplexing (OFDM) systems

In this paper, we present an iterative approach for the cancellation of phase errors induced by local oscillators in anOfdm receiver as well as the distortion resulting from nonlinear amplifiers. We investigate the influence of several parameters on the system performances, such as the modulation scheme, the number of carriers and the clipping ratio. Simulation results prove the effectiveness of the proposed algorithm for the cancellation of phase errors and non-linear distortion. We show that an error floor occurs for high values of the phase noise or the clipping ratio. This effect can be alleviated using an appropriate channel coding scheme, in conjunction with our iterative algorithm, for the correction of residual errors. We also show that the proposed algorithm complexity is nearly a linear function of the number of sub-carriers.