远传压力表示值和电信号的同步检定

介绍了远传压力表的组成和工作原理、主要功能，阐述了远传压力表同步检定的必要性及同步检定与调整的方法。     

正确使用带远传液体容积式流量计的检定误差

带远传的液体容积式流量计按检定规程的要求,只需检定仪表系数Ｋ和基本误差Ｅ和基本误差Ｅ,这两个数值只能作为用脉冲输出进的计量依据。但是由于带远传的液体容积式流量计同时带有表头显示,文章就如何使用检定证书上给出的仪表基本误差推算仪表表头指示的误差及使用表头指示值计算出表头计划的实际值等问题予以论述。     

单元接线机组的远跳与远传功能解析

目前,越来越多的220kV及以上电压等级输电线路主保护都采用光纤作为数据交换通道。利用数字光纤通道,不仅交换两侧的电流数据,同时也交换开关量信息,从而实现一些辅助功能,其中包括远传与远跳功能。阐述远传与远跳功能的原理及区别,并利用具体的二次回路图及检验方法来讲解远传与远跳功能是如何实现的。     

基于AT89C51单片机的热能表的设计

提出了一种基于AT89C51单片机的远传热能表的设计方案。介绍了系统设计中硬件、软件的设计思路、给出了原理框图。     

磁浮子液位计在长庆油田数字化建设中的应用

正远传式磁浮子液位计是一种具有就地指示和远传功能的液位测量仪表,广泛用于石油、化工、电力等行业的各种液体贮罐、分离罐、加热器、水箱等容器的液位现场指示和远程监控。一、磁浮子液位计的组成及工作原理1.磁浮子液位计的组成远传式磁浮子液位计由磁浮子、工作筒、指示器、远传变送器组成,如图1所示。     

远传水表技术基础分析

随着供水部门以及其他市场对远传水表的需求日益增加,以及科技不断发展,远传水表的技术也在不断的革新,文章就远传水表技术基础分析。     

如何使远传三表计量系统准确可靠

一、远传表具的选型 业内人士普遍认为，造成系统计量不准的最重要原因来自于远传表具，这一点已被近几年实践证明。远传表的核心部分只有一两个元器件，这可能正是造成远传三表计量不准的原因。主要问题出在以下几个方面：1．感应临界点的机械振动造成误差。2．外界及人为磁干扰造成误差。3．生产运输过程中对元器件造成损坏。     

正确使用带远传液体容积式流量计的检定误差

文章就带远传的液体容积式流量计能否使用检定证书给出的仪表精度直接作为表头指示精度,如何用表头指示值计算出该表计量的实际值,提出相应的观点。     

推进水表远传系统在中小城市的应用

中小城市的人口占全国城镇人口的四分之一，若是全部实施水表远传系统，每年能够节约的自来水量可观。不仅仅是节水作用突出，水表远传系统也将提高人民的生活水平和自来水公司的效益。针对中小城市的特点，提出了适合中小城市实施的水表远传方案。     

计量检测数据无线远传开发应用

本文介绍了一种计量检测无线远传开发和应用.该系统能够实现计量检测数据无线远传,便于市场监管部门远程监测管理,并在此基础上,开发了基于该系统的实际产品,应用效果良好.     

Fractional Radon transform: definition

In this paper a novel fractional transformation for which we coin the term the fractional Radon transform is defined. This transform generalizes the Radon transform and combines it with the fractional Fourier transform. Both transformations are useful tools for invariant pattern recognition, tomography, and signal processing. Some of the properties of the new transformation, as well as further directions for investigation, are presented.     

基于变尺度随机共振的冲击信号自适应提取与识别方法

针对不同设备故障会产生不同冲击信号类型的问题,为了克服传统指标不能区分冲击信号类型的不足,本文分析了冲击信号峭度值和近似熵的特性,将两个指标相结合,构造冲击信号特征系数,在此基础上提出了一种基于变尺度随机共振的冲击信号自适应提取与识别方法,实现强噪声环境中弱冲击信号的提取与识别。最后,通过仿真验证该方法的有效性和可行性。     

Image restoration by transformation of signal-dependent noise to signal-independent noise

A transformation to convert signal-dependent noise corrupting an image to additive Gaussian signal-independent noise is derived in this paper. Wiener filtering techniques using a Markovian covariance model for the image signal are applied to the transformed data followed by an inverse transformation to restore the degraded image. An ad hoc technique using contrast manipulation to adaptively convert signal-dependent noise to signal-independent noise is also described. The results of the computer simulations designed to evaluate the performance of these techniques are also presented.     

Remote sensing of mechanical properties of materials using a novel ultrasound transducer and signal processing

An ultrasound-based remote sensing method to evaluate the mechanical properties of materials is presented. This method consists of a disk-shaped, piezoelectric transducer, operating at its resonance frequency, and a phase-shifted, feedback circuit. Mechanical parameters are derived by analyzing the signal contained in the phase-shifted values of the reflected signal. It is concluded that, using this novel transducer system and signal processing, remote mechanical measurements can be made. Such measurements obviate the need to apply the force-deformation approach and may be used to enable stiffness imaging.     

Displacement measurements using a self-mixing laser diode under moderate feedback

A semiconductor laser subject to moderate optical feedback has been used to design an interferometric displacement sensor. The autoadaptative signal processing presented in this paper has been computed in order to improve the accuracy of such a sensor. This setup has been successfully tested for both harmonic and aleatory displacements of a remote piezoelectric actuator with a maximum accuracy of 40 nm.     

家庭远程医疗监护报警和咨询智能系统

介绍了家庭远程医疗监护和咨询智能系统，它综合运用数据融合、数据挖掘、小波分析、模式识别、人工智能等技术，能自动进行监护数据分析和异常情况识别及网络报警、远程实时诊断。给出了系统的硬件组成框图，家庭端软件结构组成框图、医疗监护中心端软件结构组成框图，介绍了系统的部分关键技术，基于小波变换的心电信号分析，结合数据挖掘和机器学习的自动建模方法，基于数据融合和识别推理的病人异常情况识别。该系统在微机Windows平台采用VC 实现，经仿真实验取得了满意的结果。     

谐波窗方法及其在裂纹故障识别中的应用

分析了谐波小波的优点。在研究谐波小波的频段分解的基础上，提出了不分层分析的谐波窗方法。推导了谐波窗的频段分析表达式，并给出了实现过程。该方法显示了小波分析的窗口伸缩功能．但避免了在基于二进的小波变换过程中，由于隔点采样导致的信息丢失现象。利用该方法对3个数字信号进行分析，体现了该方法对近频信号和微弱瞬态信号的识别能力，也体现了该方法对淹没在强噪声中微弱周期信号的提取能力。利用该方法，对某汽车齿轮箱的裂纹故障产生的原因进行振动信号的频域识别，得到了满意结果。     

水下小孔径阵列远程目标检测方法研究

匹配滤波器频域自适应线谱增强方法是一种基于递归算法的非线性滤波技术,它大大提高了匹配滤波器的检测性能.针对当前该技术使用窄带信号作为发射信号存在可利用的带宽有限,不能充分发挥自适应线谱增强器性能的问题,文章提出将该技术与宽带信号相结合来检测远程目标.仿真显示,该方法在低信噪比条件下获得了较高的信噪比增益和检测概率.海试...     

Synchronization Techniques for Power Quality Instruments

The measurement of voltage characteristics in power systems requires the accurate estimation of the power supply frequency and signal synchronization, even in the presence of disturbances. The authors developed and tested two innovative techniques for instrument synchronization. The first is based on signal spectral analysis techniques performed by means of the Chirp- transform analysis. The second is a phase-locked loop (PLL) software based on a time-domain coordinate transformation and an innovative phase-detection technique. To evaluate how synchronization techniques are adversely affected by the application of a disturbing influence, experimental tests were carried out, taking into account the requirements of the standards. The proposed techniques were compared with a standard hardware solution. In this paper, the proposed techniques are described, the experimental results are presented, and the accuracy specifications are discussed.     

How to Apply Nonlinear Subspace Techniques to Univariate Biomedical Time Series

In this paper, we propose an embedding technique for univariate single-channel biomedical signals to apply projective subspace techniques. Biomedical signals are often recorded as 1-D time series; hence, they need to be transformed to multidimensional signal vectors for subspace techniques to be applicable. The transformation can be achieved by embedding an observed signal in its delayed coordinates. We propose the application of two nonlinear subspace techniques to embedded multidimensional signals and discuss their relation. The techniques consist of modified versions of singular-spectrum analysis (SSA) and kernel principal component analysis (KPCA). For illustrative purposes, both nonlinear subspace projection techniques are applied to an electroencephalogram (EEG) signal recorded in the frontal channel to extract its dominant electrooculogram (EOG) interference. Furthermore, to evaluate the performance of the algorithms, an experimental study with artificially mixed signals is presented and discussed.