OA系统和清华紫光档案系统跨平台数据接口的开发

根据广西电网公司信息化发展现状，需要将基于Domino开发平台的OA系统数据，导入以SQL Server作为数据库的档案系统，而接口的最大难点就在于如何将数据在不同的数据库平台上传送；介绍了Dormno和SOL Server的各自特点；并试图通过“ODBC”数据通道的引入，在OA系统中建立一个跨平台数据接口，实现数据从Domino往SOL Server数据库的传送。     

基于ARM的心电信号检测

为了更好地解决心电信号的采集和处理问题,设计了以ARM微处理器LPC2368为控制核心,采用嵌入式μC/OS_Ⅱ操作系统的心电信号检测系统。将微弱的心电信号经过放大滤波处理后提取出来,利用A/D转换器将其转换为数字信号,通过串口上传到PC上进行分析处理;也可以在ARM上实现对心电信号的实时滤波、基于差分方法的QRS波检测以及心率计算。经测试,该系统实现了对心电信号的实时采集、存储、显示、数据传输、数字滤波及QRS波检测等功能,达到了预期目标。     

Robustness study of ECG biometric identification in heart rate variability conditions

Electrocardiogram (ECG) has been actively proposed as an aliveness biometric for years. In realistic application, this type of biometrics still needs to be verified in some conditions related to the practical use. Therefore, we propose in this paper the study of two themes that concern its realistic application. First, the single beat of an electrocardiogram (SB‐ECG) is used as the ECG feature, which aims to decrease the time to acquire the ECG from the individual. Second, for the robustness study of ECG features to heart rate variability (HRV), we investigate the relation between the correct identification and the HRV conditions. The HRV‐ECG data is set up and collected by using the Bio‐Pac system. The overall processes of the proposed method are the following: Continuous wavelet transform (CWT) is used to analyze each SB‐ECG. Then the root‐mean square (RMS) value of total energy of the wavelet coefficients of each P, QRS, and T segment is calculated. Next, the Fisher linear discriminant analysis (FLDA) is applied to all sets of the RMS value for dimension reduction. Lastly, the normalized Euclidean distance is implemented as the classifier. The experimental results demonstrate that, with the proposed method, the classification achieves 97% accuracy and the robustness study achieves over 80% accuracy with HRV‐ECG change up to 20%. © 2014 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

智能手机上心电信号R波的检测

选用墨西哥帽小波变换在智能手机上对心电数据进行预处理,并采用时-频域结合特征点位置信息的方法对R波进行检测.针对传统阈值法在R波检测中存在的一些问题进行改进,提出使用对频域数据进行一阶差分取绝对值,通过求极值的方法来检测倒置R波.通过使用MIT-BIH标准心律失常数据库的心电信号数据做为样本数据进行实验,实验表明该算法能够准确检测R波的特征值,最后将该算法应用到Android智能手机,效果令人满意.     

Atrial fibrillation and waveform characterization

The surface electrocardiogram (ECG) is a convenient, cost effective, and noninvasive tool for the study of atrial fibrillation (AF). It can be used to examine the hypothesized mechanisms of AF as well as to quantify and assess the effect of electrophysiological remodeling and the effectiveness of treatment on different types of AF. Time domain methods can be used to characterize the signal in the surface ECG. The authors described observations that can be obtained directly from the signal, such as the general characteristics of AF in the surface ECG and the ventricular response to AF. A discussion on commonly used methods to characterize atrial activity is also presented. These methods include cancellation techniques, vector analysis, and autocorrelation. Observations show that combining time and frequency domain methods provides a more thorough understanding of the characteristics of the atrial activity in the surface ECG. Whether the study of atrial activity in the surface ECG can be used to distinctively distinguish between different mechanisms of AF is not yet known, but further investigation can improve our understanding of these mechanisms and help with the management of this common arrhythmia     

Effect of operational amplifier imperfections on single amplifier filters

A general method is given for the analysis of single amplifier RC-active filters using nonideal operational amplifiers (OA). It is shown that the output resistance of the OA has a significant effect in the passband and stopband in addition to the known deviations due to the finite gain—bandwidth product. The nonideal transfer functions in the factorized form, giving clearer concept of the effects of the nonideal OA, are obtained using some realistic approximations based on the typical specifications of modern general purpose OA. Expressions thus obtained closely follow the exact transfer functions, as demonstrated in the illustrative examples given, and their validity is confirmed by the experimental results.     

电力企业办公自动化系统设计概述

以唐山滦南县电力公司办公自动化建设为背景,结合电力企业的实际情况,在需求分析的基础上,提出电力企业办公自动化系统的基本目标,并阐述系统的结构设计和功能设计,给出了一个结合B/S和Web技术的电力企业办公自动化系统.     

一种面向心电信号处理的奇异谱分析改进算法

心电图(ECG)作为人体的关键生理信号被广泛应用于医疗领域,但在采集过程中心电信号容易受到噪声干扰而影响 信号质量。为此,设计了一种奇异谱分析(SSA)的改进算法用于心电信号降噪处理。奇异谱分析改建算法是在 SSA中的主 元重组(grouping)阶段引入逻辑回归(LR) 算法,将主元重组方式改进为自动重组,实现面向心电信号的 SSA 自监督降噪处 理。使用基于 AD620 的心电信号采集装置,构建53条心电信号测试集进行验证,使用奇异谱分析的改进算法,主元自动选择 的准确性为98.68%,重构的心电信号信噪比(SNR)由10.43 dB平均提高到20.17 dB,能够有效提取出清晰的PQRST 波,使 其在医疗领域心电信号检测与降噪方面具有很好的实用化前景。     

Proposed network structures and combined adaptive algorithms for electrocardiogram signal denoising

An electrocardiogram (ECG) signal is a record of the electrical activities of heart muscle and is used clinically to diagnose heart diseases. An ECG signal should be presented as clear as possible to support accurate decisions made by doctors. This article proposes different combinations of combined adaptive algorithms to derive different noise-cancelling structures to remove (denoise) different kinds of noise from ECG signals. The algorithms are applied to the following types of noise: power line interference, baseline wander, electrode motion artifact, and muscle artifacts. Moreover, the results of the suggested models and algorithms are compared with those of conventional denoising tools such as the discrete wavelet transform, an adaptive filter, and a multilayer neural network (NN) to ensure the superiority of the proposed combined structures and algorithms. Furthermore, the hybrid concept is based on dual, triple, and quadruple combinations of well-known algorithms that derive adaptive filters, such as the least mean squares, normalized least mean squares and recursive least squares algorithms. The combinations are formulated based on partial update, variable step-size (VSS), and second iterative VSS algorithms, which are considered in different combinations. In addition, biased NN and unbiased linear neural network (ULNN) structures are considered. The performance of the different structures and related algorithms are evaluated by measuring the post-signal-to-noise ratio, mean square error, and percentage root mean square difference.     

基于77GHz毫米波雷达感知的生命体征检测方法

本文针对在室内复杂环境中非接触式测量呼吸频率(HR)和心率(BR)时,存在准确度较低的问题,提出一种基于77GHz毫米波雷达感知的生命体征检测方法,通过在距离雷达不同距离进行多次实验,以Mindray心电监测仪测量数据为参考,验证本文方法的准确率。首先,通过脉冲间非相干积累技术处理多脉冲中频信号,提高信号的信噪比（SNR）和信号幅值。接着,采用基于距离维FFT频谱与CA-CFAR自适应门限的目标检测方法,从室内复杂环境中提取出人体目标相位信息,并使用Fir带通滤波器分离出呼吸和心跳信号,通过改进的平滑滤波结合相位二阶差分的方法,去除噪声和减小呼吸谐波对心跳信号的影响。之后,使用Root-MUSIC算法获得HR和BR。实验结果表明：本文方法得到的HR和BR的平均绝对误差率分别小于5.08%和2.61% ,平均绝对误差为0.94bpm和1.97bpm,因此,本文方法能够提高测量准确度。     

A novel DWT method for ECG noise elimination

An electrocardiogram (ECG) often contains various types of noises and artifacts that might lead to wrong analysis. Recently, many techniques based on discrete wavelet transform (DWT) for ECG noise elimination have been proposed. Determination of the number of decomposition levels, which could vary with the sampling rate (frequency sampling), is one of the main issues in DWT. This letter presents an automatic index, called mean power frequency (MPF) and is independent of the sampling rate, for stopping decomposing process when it achieves the optimum number of decomposition levels. The effectiveness of this scheme is expressed by the signal‐to‐noise ratio (SNR), mean square error (MSE), and correlation coefficient (CC) between the pure and corrected ECG. The results indicate that the applied method can remove Gaussian noise efficiently. © 2015 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

On the realization of current transfer function using voltage amplifiers

Current transfer function is a feature of current‐mode filters. Current‐mode filters have so far been realized principally using current amplifiers and current conveyors. Some current‐mode filter architecture using operational amplifiers have also been reported. In this article it is shown that by using the principles of transposed network and nullor model for the active device, a current transfer function can be realized in a very simple way using a voltage amplifier, i.e. operational amplifier (OA). The key concept is the knowledge that each ideal (i.e. infinite gain) controlled source is exactly equivalent to a nullor. Thus, a voltage‐mode filter implemented using an ideal three terminal (output, input and ground) OA can be very easily converted to a current‐mode filter using the same OA. The principle has been illustrated by considering single‐OA‐ and multi‐OA‐based second‐order voltage‐mode filters. SPICE simulation results are provided to validate the theoretical concept. Copyright © 2006 John Wiley & Sons, Ltd.     

电子政务办公自动化的建设

从应用的角度，阐述了目前电子政务自动化系统应用中存在的一些不足，提出了办公自动化系统应具有的基本功能模块。从技术开发角度提出了开发、改进系统时的几点注意事项，明确了办公自动化的发展方向。     

OA系统公文流转安全的管理措施探析

随着信息技术的迅猛发展和互联网的广泛应用,办公自动化系统（OA系统）已成为我国政府和众多企业的日常工作平台,但由于计算机网络自身的弱点和外界的原因,OA系统公文流转安全受到一定威胁,从OA系统公文流转的安全需求分析着手,研究基于PDCA循环模式的OA系统公文流转安全管理持续改进框架,并给出相关对策建议,希望能为我国OA系统公文流转安全管理提供一些有价值的参考。     

Design of efficient fractional operator for ECG signal detection in implantable cardiac pacemaker systems

A low power and high-performance digital electrocardiogram (ECG) detector has become a basic requirement in modern implantable cardiac pacemakers. A fractional operator-based digital ECG detector for modern pacemaker systems is proposed in this work. Instead of conventional thresholding, an adaptive slope prediction threshold is utilized for the detection of ECG peaks. A stochastic search-based algorithm, namely, cuckoo search algorithm, is used to design an optimal fractional operator that is used for ECG denoising. It has been found that the proposed adaptive slope prediction threshold increases the QRS complex detection performance. A low detection error rate (DER) ranges from 0.01% to 0.56%, positive predictivity (P+) ranges from 99.32% to 99.98%, sensitivity (Se) ranges from 99.45% to 99.98%, and a detection accuracy (Acc) ranges from 99.43% to 99.96% for different databases are achieved for the proposed ECG detector, which is better compared with the existing ECG detectors. The proposed design of fractional order operator based on the lattice wave digital filter (LWDF) requires a minimum number of the multipliers for its structural realization.     

河南省电力公司OA系统数据灾难恢复方案的设计与实施

针对目前计算机网络中的不安全因素,研究在电力系统中利用灾难恢复技术,为保证OA系统数据安全可靠而采取的措施,提出OA系统的数据备份及灾难恢复方案。通过该方案在河南省电力公司OA系统中的实施应用,保证了OA系统数据的实时性和完整性,提高了系统的安全性和可靠性,增强了系统的可用性和灵活性。     

Improved ICA algorithm for ECG feature extraction and R-peak detection

Electrocardiogram (ECG) signal transmission and monitoring plays a paramount role in long-term cardiac monitoring and analysis to provide remote health care in time, especially for the postoperative people and people in remote areas. The accuracy of ECG signals is of fundamental importance in cardiac diagnosis like R-peak detection. So we need to incorporate analytical methods in existing healthcare systems, to capture more meaningful ECG components and to represent physical cardiac sources more clearly. With this aim, hardware optimized FCAICA (fast confluence adaptive independent component analysis) algorithm is proposed to extract pure ECG components from the ECG mixtures. The extracted signals are then subjected to R-peak detection for further analysis. The proposed improved fast confluence adaptive independent component analysis (IFCAICA) method occupies less hardware resources, consumes low power, improves accuracy, and sensitivity in R-peaks detection. In 0.18 nm technology, the IFCAICA consumes 10.13 mW of power and operates with 3.4 MHz operating frequency.     

基于DSP的心电信号检测系统

心电信号的检测是研究心电病理特征的前提,是心电信号分析仪的重要组成部分.本文介绍了一种基于DSP的心电信号采集和分析系统.根据心电信号的特点,本系统采用AgCl电极作为心电信号传感器,结合AD620为主的前置放大电路进行模拟信号的采集.以TMS320VC5509低功耗DSP和CPLD为主进行数字系统设计.在DSP中编程实现数字滤波器的设计,最终得到P、T和QRS复波特征明显的ECG.本系统功耗小,成本低,精度高,达到了医疗仪器的设计要求.     

调度自动化系统接入OA安全防护系统设计

随着信息化工作的不断深入,管理机关要求将调度自动化系统接入OA网,但调度自动化系统接入OA后的安全防护成了关键问题,其解决的方法是将调度自动化系统划分区域,并加装单向隔离设备,文章介绍了调度自动化系统接入办公OA网时安全保护系统的设计方法。