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Implementation of the characteristic functions approach to measurement uncertainty evaluation 特征函数法在测量不确定度评定中的应用
IF 0.1 Q4 INSTRUMENTS & INSTRUMENTATION Pub Date : 2022-03-31 DOI: 10.24027/2306-7039.1.2022.258818
V. Witkovský
Probability distributions suitable for modelling measurements and determining their uncertainties are usually based on a standard approximation approach as described in GUM, i.e. the GUM uncertainty framework (GUF), using the law of uncertainty propagation (also known as the delta method) or a more accurate method based on the law of probability propagation calculated using the Monte Carlo method (MCM). As an alternative to GUF and MCM, we present a characteristic function approach (CFA), which is suitable for determining measurement uncertainties by using the exact probability distribution of a measured quantity in linear measurement models by inverting the associated characteristic function (CF), which is defined as a Fourier transform of the probability density function (PDF). In this paper, we present the current state of the MATLAB implementation of the characteristic function approach (the toolbox CharFunTool) and illustrate the use and applicability of the CFA for determining the distribution and uncertainty evaluation with a simple example. The proposed approach is compared with GUM, MCM and the kurtosis uncertainty method (KUM).
适用于建模测量并确定其不确定性的概率分布通常基于GUM中描述的标准近似方法,即GUM不确定性框架(GUF),使用不确定性传播定律(也称为delta方法)或基于使用蒙特卡罗方法(MCM)计算的概率传播定律的更准确的方法。作为GUF和MCM的替代方案,我们提出了一种特征函数方法(CFA),该方法适用于通过反转相关特征函数(CF)来使用线性测量模型中测量量的精确概率分布来确定测量不确定性,该特征函数被定义为概率密度函数(PDF)的傅立叶变换。在本文中,我们介绍了特征函数方法(工具箱CharFunTool)的MATLAB实现现状,并通过一个简单的例子说明了CFA在确定分布和不确定度评估中的使用和适用性。将所提出的方法与GUM、MCM和峰度不确定度方法(KUM)进行了比较。
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引用次数: 0
Measurements of near-surface radial profiles of electrophysical characteristics of cylindrical objects by the eddy current method using a priori data 利用先验数据涡流法测量圆柱形物体电物理特性的近表面径向分布
IF 0.1 Pub Date : 2022-03-31 DOI: 10.24027/2306-7039.1.2022.258678
V. Halchenko, A. Storchak, V. Tychkov, R. Trembovetska
A new multiparameter express method for eddy-current measurement of radial near-surface profiles of electrophysical parameters of cylindrical control objects with a priori accumulation of information about them is proposed. The method combines in-situ measurements and model calculations using high-performance computing technologies of artificial intelligence based on neural networks, carried out both in advance in order to obtain specific information about objects, and directly in the process of performing measurements to quickly obtain a result. Mathematically, the method is based on the unique ability to quickly solve Maxwell's equations as a result of its approximation by deep neural networks without actually explicitly executing this solution. This allows deep learning to be used not only in the forward direction, but also in the opposite direction, i.e. apply to solve inverse measuring problems. The method is universal and can be extended to multiparameter measurement control with simultaneous additional determination of the diameter of a cylindrical object. The adequacy of the proposed method by numerical experiments is proved; examples of the implementation of all stages of its application are given. Algorithms and a complex of programs in the Python 3 environment have been created, which make it possible to practically implement the method. The profile measurement accuracy established on model calculations is characterized by maximum relative errors not exceeding 0.5%, provided that the probe signal is perfectly fixed. It is possible to generalize the use of the proposed method to similar eddy current measurements with surface probes of profiles of material parameters of flat objects.
提出了一种新的多参数表达方法,用于涡流测量圆柱形控制对象的电物理参数的径向近表面轮廓,并先验地积累有关它们的信息。该方法使用基于神经网络的高性能人工智能计算技术,将现场测量和模型计算相结合,既可以提前进行以获得有关物体的特定信息,也可以直接在进行测量的过程中快速获得结果。在数学上,该方法基于快速求解麦克斯韦方程组的独特能力,这是通过深度神经网络进行近似的结果,而无需实际明确执行该解。这使得深度学习不仅可以正向使用,还可以反向使用,即应用于解决反向测量问题。该方法具有通用性,可扩展到多参数测量控制,同时额外确定圆柱形物体的直径。数值实验证明了该方法的充分性;文中给出了其应用各个阶段的实现实例。已经在Python3环境中创建了算法和复杂的程序,这使得实际实现该方法成为可能。在模型计算中建立的轮廓测量精度的特点是最大相对误差不超过0.5%,前提是探头信号完全固定。可以将所提出的方法推广到使用平面物体材料参数轮廓的表面探针进行类似的涡流测量。
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引用次数: 0
Precision active power measuring channel 精密有功功率测量通道
IF 0.1 Q4 INSTRUMENTS & INSTRUMENTATION Pub Date : 2021-12-31 DOI: 10.24027/2306-7039.4.2021.250410
D. Ornatskyi, S. Yehorov, M. Kataieva, M. Graf, Dmytro Shcherbyna
The article is devoted to increasing the reliability, noise protection and improving the metrological characteristics of active power measuring converters. Much attention is paid to the problem of developing effective methods for constructing structural diagrams of active power measuring converters. This is explained by the growing requirements for the basic metrological characteristics of active power measuring converters as elements of information – measuring systems. The main attention in the work is paid to the development of ways to correct the influence of destabilizing factors in working conditions. The undoubted advantage of the work is a thorough analysis of the instrumental errors of the measuring channel, the original means of correction of the phase error and the error due to the limited suppression coefficients of in-phase interference. The obtained simulation results in the Electronics Workbench environment made it possible to determine the most effective way to protect against interference.
本文致力于提高有源功率测量转换器的可靠性、噪声防护和改善其计量特性。开发有效的方法来构建有源功率测量转换器的结构图是一个备受关注的问题。这可以通过对作为信息测量系统元件的有功功率测量转换器的基本计量特性的日益增长的要求来解释。工作中的主要关注点是制定纠正工作条件中不稳定因素影响的方法。这项工作无疑的优点是深入分析了测量通道的仪器误差、相位误差的原始校正方法以及由于同相干扰抑制系数有限而产生的误差。在Electronics Workbench环境中获得的模拟结果使确定最有效的防干扰方法成为可能。
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引用次数: 0
Application of systems thinking to the establishment of metrological traceability chains 系统思维在计量溯源链建立中的应用
IF 0.1 Q4 INSTRUMENTS & INSTRUMENTATION Pub Date : 2021-12-30 DOI: 10.24027/2306-7039.4.2021.250348
O. Velychko, T. Gordiyenko
International agreements in the field of metrology and accreditation of calibration laboratories are the basis for establishing global metrological traceability. Important elements of metrological traceability are calibration of measurement standards and measuring instruments, assessment of measurement uncertainty. The International Laboratory Accreditation Cooperation has a specific policy regarding on traceability of measurement results and estimation of measurement uncertainty in calibration. The partial concept diagram around metrological traceability in accordance with the International Vocabulary of Metrology is proposed. This diagram contains a total of nine metrological concepts, which have most of the associative relations. There are associative relations between the concept of metrological traceability chain and concepts of metrological traceability, measurement standard, calibration and calibration hierarchy, and through the concept of measurement standard with the concept of measurement uncertainty. Systems thinking to the analysis of state of proposed terminological system around metrological traceability was applied. For construction of generalized metrological traceability chain, all the established properties of the system elements around the terminology system of metrological traceability were taken into account. Generalized metrological traceability chain for different levels of the calibration hierarchy was proposed. The proposed chain can be used to develop appropriate chains for specific areas of measurement. To achieve this, it is necessary to determine the specific measured value, the required measurement uncertainty for different levels of the calibration hierarchy and select the necessary measurement standards. Such schemes should be used in national metrology institutes and calibration laboratories.
计量领域的国际协议和校准实验室的认证是建立全球计量可追溯性的基础。计量可追溯性的重要组成部分是测量标准和测量仪器的校准、测量不确定度的评定。国际实验室认可合作组织有一项关于测量结果可追溯性和校准中测量不确定度估计的具体政策。根据《国际计量词汇》提出了计量溯源的局部概念图。该图共包含九个计量概念,它们具有大多数的关联关系。计量溯源链的概念与计量溯源、测量标准、校准和校准层次等概念之间存在关联关系,并通过测量标准的概念与测量不确定度的概念之间存在联系。将系统思维应用于围绕计量溯源的拟议术语系统的状态分析。在广义计量溯源链的构建中,考虑了计量溯源术语体系中系统元素的所有既定性质。提出了适用于不同校准层次的广义计量溯源链。所提出的链可用于为特定的测量领域开发适当的链。为了实现这一点,有必要确定特定的测量值、不同校准等级所需的测量不确定度,并选择必要的测量标准。国家计量机构和校准实验室应使用此类方案。
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引用次数: 2
Ensuring the validity of the results of calibrations and tests by statistical methods 通过统计方法确保校准和测试结果的有效性
IF 0.1 Q4 INSTRUMENTS & INSTRUMENTATION Pub Date : 2021-12-30 DOI: 10.24027/2306-7039.4.2021.250375
Alexander Kolbasin
According to the requirements of ISO/IEC 17025:2017, the validity of test and calibration results is ensured, inter alia, by intralaboratory check of the results obtained. In this case, it is preferable to use statistical methods. The ISO 5725 standards define a number of such methods, but the choice of specific methods is left to the laboratory, taking into account the requirements for the adequacy of the effort, resources and time for the purposes of the work performed and the risks of obtaining inappropriate results. In this case, the laboratory itself must in a certain way determine which objects of calibrations (tests) should be predominantly used in checks and what frequency of checks should be foreseen. In connection with the increase in the accuracy and complexity of measuring systems, the need to apply the methods of the theory of random processes becomes more and more obvious. It is shown that the use of the Poincaré plot makes it possible to comprehensively, effectively and visually evaluate changes in the measuring process from the point of view of the dynamics of the obtained measurement results. The results of the check, in particular, the intermediate precision, make it possible to obtain a more realistic evaluation of measurement uncertainty in accordance with ISO 21748. The paper analyses some practical approaches (of varying degrees of complexity) to intralaboratory checks of the validity of calibration (test) results.
根据ISO/IEC 17025:2017的要求,通过对获得的结果进行实验室内检查,确保测试和校准结果的有效性。在这种情况下,最好使用统计方法。ISO 5725标准定义了许多此类方法,但具体方法的选择由实验室决定,同时考虑到所执行工作所需的努力、资源和时间的充分性要求以及获得不适当结果的风险。在这种情况下,实验室本身必须以某种方式确定哪些校准(测试)对象应主要用于检查,以及应预见检查频率。随着测量系统精度和复杂性的提高,应用随机过程理论的方法变得越来越明显。结果表明,使用庞加莱图可以从所获得的测量结果的动力学角度全面、有效和直观地评估测量过程中的变化。检查结果,特别是中间精度,使其能够根据ISO 21748获得更真实的测量不确定度评估。本文分析了实验室内校准(测试)结果有效性检查的一些实用方法(具有不同程度的复杂性)。
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引用次数: 0
Minimization of errors in discrete wavelet filtering of signals during ultrasonic measurements and testing 超声波测量和测试过程中信号离散小波滤波误差的最小化
IF 0.1 Pub Date : 2021-12-30 DOI: 10.24027/2306-7039.4.2021.250433
Y. Taranenko, R. Mygushchenko, O. Kropachek, G. Suchkov, Yu. O. Plesnetsov
Error minimizing methods for discrete wavelet filtering of ultrasonic meter signals are considered. For this purpose, special model signals containing various measuring pulses are generated. The psi function of the Daubechies 28 wavelet is used to generate the pulses. Noise is added to the generated pulses. A comparative analysis of the two filtering algorithms is performed. The first algorithm is to limit the amount of detail of the wavelet decomposition coefficients in relation to signal interference. The minimum value of the root mean square error of wavelet decomposition signal deviation which is restored at each level from the initial signal without noise is determined. The second algorithm uses a separate threshold for each level of wavelet decomposition to limit the magnitude of the detail coefficients that are proportional to the standard deviation. Like in the first algorithm, the task is to determine the level of wavelet decomposition at which the minimum standard error is achieved. A feature of both algorithms is an expanded base of discrete wavelets ‒ families of Biorthogonal, Coiflet, Daubechies, Discrete Meyer, Haar, Reverse Biorthogonal, Symlets (106 in total) and threshold functions garotte, garrote, greater, hard, less, soft (6 in total). The model function uses random variables in both algorithms, so the averaging base is used to obtain stable results. Given features of algorithm construction allowed to reveal efficiency of ultrasonic signal filtering on the first algorithm presented in the form of oscilloscopic images. The use of a separate threshold for limiting the number of detail coefficients for each level of discrete wavelet decomposition using the given wavelet base and threshold functions has reduced the filtering error.
考虑了超声波流量计信号离散小波滤波的误差最小化方法。为此,产生包含各种测量脉冲的特殊模型信号。Daubechies 28小波的psi函数用于生成脉冲。噪声被添加到生成的脉冲中。对两种滤波算法进行了比较分析。第一种算法是限制与信号干扰相关的小波分解系数的细节量。确定从没有噪声的初始信号在每个级别恢复的小波分解信号偏差的均方根误差的最小值。第二种算法对每个级别的小波分解使用单独的阈值来限制与标准偏差成比例的细节系数的大小。与第一种算法一样,任务是确定实现最小标准误差的小波分解级别。这两种算法的一个特点是离散小波的扩展基础——双正交、Coiflet、Daubechies、discrete Meyer、Haar、反向双正交、Symlets(共106个)和阈值函数garotte、garrote、great、hard、less、soft(共6个)。模型函数在两种算法中都使用了随机变量,因此使用平均基数来获得稳定的结果。给定算法构造的特征,可以揭示超声信号滤波对以示波器图像形式呈现的第一种算法的效率。使用单独的阈值来限制使用给定的小波基和阈值函数的离散小波分解的每个级别的细节系数的数量已经减少了滤波误差。
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引用次数: 0
Reduction of the auto seismic component of error of a ballistic laser gravimeter by excitation of an induction-dynamic catapult from an AC voltage source 交流电压激励感应动力弹射器降低弹道激光重力仪自震误差分量
IF 0.1 Pub Date : 2021-12-30 DOI: 10.24027/2306-7039.4.2021.250401
V. Bolyukh, Оleksandr Vinnichenko, A. Omelchenko
The purpose of the study is to analyse the influence of the excitation of an induction-dynamic catapult of a ballistic laser gravimeter from an AC voltage source at different frequencies on electromechanical indicators that provide a reduced value of the auto seismic component of error in measuring the gravitational acceleration g due to a decrease in the recoil force. A mathematical model of the gravimeter catapult when excited from an AC voltage source is proposed, taking into account the interrelated electrical, magnetic and mechanical processes. The nature of the electromechanical processes in the catapult of the gravimeter with such excitation has been established. It is shown that a phase shift occurs between the currents in active elements, as a result of which positive (repulsive) pulses of the electrodynamic force alternate with negative (attractive) pulses of force. A criterion for the efficiency of the gravimeter catapult has been introduced, taking into account the maximum value of push of the test body at the smallest values of the electrodynamic force and current of the inductor winding. It was found that the highest efficiency of the gravimeter catapult is provided at a frequency of 250 Hz, at which the catapult efficiency is 3.5 times higher than at a frequency of 50 Hz. It is shown that the transition from the method of excitation of an induction-dynamic catapult with one short pulse to excitation from an AC voltage source makes it possible to reduce the uncertainty in measuring the gravitational acceleration.
本研究的目的是分析不同频率的交流电压源对弹道激光重力仪感应动态弹射器的激励对机电指示器的影响,该指示器在测量重力加速度g时由于后坐力的减小而提供误差的自震分量的减小值。考虑到相互关联的电、磁和机械过程,提出了重力仪弹射器在交流电压源激励下的数学模型。建立了重力仪弹射器在这种激励下的机电过程的性质。结果表明,有源元件中的电流之间发生相移,其结果是电动力的正(排斥)脉冲与力的负(吸引)脉冲交替。介绍了重力仪弹射器效率的一个标准,该标准考虑了在电感器绕组的电动力和电流的最小值下试验体的最大推力值。已经发现,重力仪弹射器的最高效率是在250Hz的频率下提供的,在该频率下弹射器效率是在50Hz的频率下的3.5倍。研究表明,从一个短脉冲的感应动力弹射器激励方法到交流电压源激励方法的转变,有可能降低重力加速度测量的不确定性。
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引用次数: 0
Intrinsic background of the beta channel of the aerosol volumetric activity monitor 气溶胶体积活动性监测仪β通道的固有本底
IF 0.1 Pub Date : 2021-12-30 DOI: 10.24027/2306-7039.4.2021.250425
A. Kozyrenko, O. Letuchyy, Andrei Pystovyi, V. Skliarov
The work is devoted to the study of the features of generation of the intrinsic background of the measuring beta channel of the aerosol monitor in real conditions of measuring the volumetric activity of aerosols, caused by radionuclides of technogenic origin. The influence of external factors on the generation of the level of the intrinsic background of the measuring channel of the monitor and its metrological characteristics is investigated. The reliability of the results of measurements of the volumetric activity of air aerosols substantially depends on the correct accounting of external factors, parameters of the monitored environment and the specified operating mode of the monitor. Aerosol volumetric activity monitors, as a rule, operate in a continuous mode, in which the aspiration method of aerosol accumulation is implemented, followed by measuring the volumetric activity of aerosols by alpha radiation and (or) beta radiation generated by technogenic radionuclides. This article describes the results of experiments on measuring the iCAM aerosol monitor’s intrinsic beta channel background under real operating conditions, and its dependence on external factors. The studies were carried out on iCAM aerosol monitors (iCAM/D and iCAM/MF modifications) manufactured by Canberra Industries Inc. in a laboratory room in normal climatic conditions with a radon volumetric activity of 35±10 Bq·m-3 and an equivalent dose rate of gamma radiation of 0.13±0.02 μSv·h-1. In modern aerosol monitors, software and hardware solutions are implemented that allow to significantly reduce the background level and, as a result, to expand the measurement range of the volumetric activity of aerosols towards low values.
本文主要研究了气溶胶监测仪在测量由技术来源的放射性核素引起的气溶胶体积活度的实际条件下,测量β通道固有本底产生的特点。研究了外部因素对监视器测量通道本底电平产生及其计量特性的影响。空气气溶胶体积活度测量结果的可靠性在很大程度上取决于对外部因素、被监测环境的参数和监测器的指定操作模式的正确计算。气溶胶体积活度监测仪通常以连续模式工作,其中采用气溶胶积聚的吸吸法,然后通过技术核素产生的α辐射和(或)β辐射测量气溶胶的体积活度。本文介绍了在实际工作条件下测量iCAM气溶胶监测仪固有通道本底的实验结果及其对外部因素的依赖关系。研究在堪培拉工业公司生产的iCAM气溶胶监测仪(iCAM/D和iCAM/MF改型)上进行,氡体积活度为35±10 Bq·m-3, γ辐射等效剂量率为0.13±0.02 μSv·h-1,气候条件正常。在现代气溶胶监测仪中,实现了软件和硬件解决方案,可以显着降低背景水平,从而将气溶胶体积活动的测量范围扩大到低值。
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引用次数: 0
Method for the numerical evaluation of the color rendering quality of matrix photodetectors 矩阵光电探测器显色质量的数值评估方法
IF 0.1 Q4 INSTRUMENTS & INSTRUMENTATION Pub Date : 2021-12-30 DOI: 10.24027/2306-7039.4.2021.250412
O. Kupko, O. Liashenko, P. Neyezhmakov, Yevhen Tymofeiev, Eduard Diumin, Natalia Mushchynska, Anatoliy Litvinenko
To objectively evaluate the color image of an architectural object when changing its spectral quality and luminance in lighting, it is necessary to ensure its accurate fixation. The measurement of the color coordinates of an object provides the fully capture of its appearance, but this does not allow to get an adequate evaluation of the visual impression without visualizing the lighting scene. This requires a thorough procedure of reproducing the same color coordinates for each point of the image and the object with the same angular coordinates. In this work, an attempt is made to develop a numerical criterion for evaluating the quality of color rendering of the camera as a fixer of color visual impression of the selected scene. The development of a numerical detailed method for evaluation of the quality of color rendering of cameras will allow capturing more reliably such a subjective concept as the correspondence of the visual impression of the real scene and the image file of this scene. The digital format, which contains information about the object, avoids the problems associated with aging of the image. The proposed method of developing ways to numerically evaluate color distortion in photography is considered on the example of digital cameras Nikon D300s, Sony DSC-H5. The described approach for the case of known spectral characteristics allows to unambiguously link the calculated reaction of the camera with the chromaticity coordinates of spectrally pure colors. Modern methods of evaluating the quality of light sources (IES TM-30-15) allow evaluation of the direction of the shift. The proposed indicator – graph E (λi) numerically characterizes the difference between the reaction of the camera and the reaction of the human eye and does not give an idea in which direction there is a difference, conditionally red or blue image compared to the natural scene, but is the simplest and most understandable to the untrained user. It is shown that with an accuracy of measuring spectral characteristics of 1% for the considered example with Nikon D300s, this indicator at different wavelengths is calculated with an uncertainty of not more than 0.002.
为了客观地评估建筑物体在照明中改变其光谱质量和亮度时的彩色图像,有必要确保其准确固定。物体的颜色坐标的测量提供了对其外观的完全捕捉,但这不允许在不可视化照明场景的情况下获得对视觉印象的充分评估。这需要对具有相同角度坐标的图像和对象的每个点再现相同颜色坐标的彻底过程。在这项工作中,试图开发一个数字标准来评估相机的颜色渲染质量,作为所选场景的颜色视觉印象的固定器。用于评估相机的色彩渲染质量的数字详细方法的开发将允许更可靠地捕捉诸如真实场景的视觉印象和该场景的图像文件的对应关系这样的主观概念。包含对象信息的数字格式避免了与图像老化相关的问题。以数码相机Nikon D300s、Sony DSC-H5为例,考虑了开发数字评估摄影中颜色失真的方法。对于已知光谱特性的情况,所描述的方法允许将所计算的相机的反应与光谱纯颜色的色度坐标明确地联系起来。评估光源质量的现代方法(IES TM-30-15)允许评估偏移的方向。所提出的指标图E(λi)在数字上表征了相机的反应和人眼的反应之间的差异,并且没有给出与自然场景相比在哪个方向存在差异的想法,条件是红色或蓝色图像,但对于未经训练的用户来说,这是最简单和最容易理解的。结果表明,对于所考虑的尼康D300s示例,测量光谱特性的精度为1%,在不同波长下计算该指示剂的不确定度不超过0.002。
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引用次数: 0
Informational uncertainty of measuring instruments 测量仪器的信息不确定度
IF 0.1 Q4 INSTRUMENTS & INSTRUMENTATION Pub Date : 2021-12-30 DOI: 10.24027/2306-7039.4.2021.250399
Gennadii Manko, Elena Titova
Recently, there has been a revival of interest in the use of the information approach in the theory of measurements. Unlike the traditional approach, information theory does not evaluate error or uncertainty, but entropy and the amount of information. This article analyzes a number of recent publications that develop ideas for the information approach. The limitations and disadvantages of both the entropy approach and the concept of uncertainty are indicated. As a compromise solution, it is proposed to use a criterion based on the Bongard’s uncertainty and useful information. The concept of information uncertainty is proposed, which is estimated by the amount of negative useful information, that is, misinformation introduced by the measuring instrument. Some methods for calculating information uncertainty are described. The problems of using the uncertainty approach are noted. This approach does not imply the use of such a generalized characteristic of measuring instruments as an accuracy class. The article proposes an analogue of the accuracy class in the form of relative informational uncertainty, expressed as a percentage. This will make it possible to evaluate the quality of the measuring instrument by a single parameter, the calculation of which requires a minimum of computational operations.
最近,人们对在测量理论中使用信息方法重新产生了兴趣。与传统方法不同,信息论不评估误差或不确定性,而是熵和信息量。本文分析了一些最近的出版物,这些出版物提出了信息方法的思想。指出了熵法和不确定性概念的局限性和缺点。作为一种折衷的解决方案,提出了一种基于邦加德不确定性和有用信息的准则。提出了信息不确定度的概念,通过测量仪器引入的负有用信息即错误信息的数量来估计信息不确定度。介绍了计算信息不确定性的几种方法。指出了使用不确定度方法的问题。这种方法并不意味着使用测量仪器的这种广义特性作为精度等级。本文以相对信息不确定性的形式提出了准确度类的类比,以百分比表示。这将使通过单个参数评估测量仪器的质量成为可能,其计算需要最少的计算操作。
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引用次数: 0
期刊
Ukrainian Metrological Journal
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