Ukrainian Metrological Journal最新文献

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Evaluation of measurement uncertainty when calibrating power analyzers of high-frequency signals in coaxial paths 同轴路径高频信号功率分析仪校准时测量不确定度的评定
IF 0.1
Ukrainian Metrological Journal Pub Date : 2022-06-30 DOI: 10.24027/2306-7039.2.2022.263889
S. Shevkun, Maryna Dobroliubova, Evhen Lapko
{"title":"Evaluation of measurement uncertainty when calibrating power analyzers of high-frequency signals in coaxial paths","authors":"S. Shevkun, Maryna Dobroliubova, Evhen Lapko","doi":"10.24027/2306-7039.2.2022.263889","DOIUrl":"https://doi.org/10.24027/2306-7039.2.2022.263889","url":null,"abstract":"Implementation of modern requirements for the quality and stability of radio communications, including the required data rate in industrial and atmospheric jamming, is impossible without accurate measurements of signal power at the output of transmitting devices in the transmitter-antenna section. Such measurements are performed using power analyzers that measure both incident and reflected waves. These parameters allow calculating the standing wave ratio, which makes it possible to ensure optimal coordination of the transmitter with antenna, the required power modes and the efficiency of the transmitter as a whole. \u0000The paper presents main results of the research on the evaluation of measurement uncertainty when calibrating of the analyzers of the throughput power of high-frequency signals in coaxial paths. \u0000The structural scheme and equations (model) of measurements, and features of calculating uncertainty budget are described. The basic principles for obtaining continuous calibration results in the whole range of measurements are revealed. An example of presenting calibration results in graphical form is given. \u0000The content of quantitative and qualitative indicators of corrections that must be taken into account during calibration to achieve the highest accuracy of measurements is revealed. It is expedient to use practical results of researches on calibration of throughput power meters in many areas connected with telecommunications and transmission of radio signals.","PeriodicalId":40775,"journal":{"name":"Ukrainian Metrological Journal","volume":null,"pages":null},"PeriodicalIF":0.1,"publicationDate":"2022-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49254181","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Bilateral comparisons on COOMET Project 684/MD/16 “Pilot comparisons of national standards in the field of gas flow” 关于COOMET项目684/MD/16“天然气流量领域国家标准试点比较”的双边比较
IF 0.1
Ukrainian Metrological Journal Pub Date : 2022-03-31 DOI: 10.24027/2306-7039.1.2022.258824
D. Serediuk, Yuriy Pelikan, Volodumur Gulyk, O. Bas
{"title":"Bilateral comparisons on COOMET Project 684/MD/16 “Pilot comparisons of national standards in the field of gas flow”","authors":"D. Serediuk, Yuriy Pelikan, Volodumur Gulyk, O. Bas","doi":"10.24027/2306-7039.1.2022.258824","DOIUrl":"https://doi.org/10.24027/2306-7039.1.2022.258824","url":null,"abstract":"Abstract\u0000The article describes the procedure for performing international bilateral comparisons of the national measurement standards of the units of gas volume and volume flow in Ukraine and Moldova. The comparisons were carried out within COOMET Project 684/MD/16 “Pilot comparisons of national standards in the field of gas flow”. The list of reference standards that took part in comparisons is indicated. The range of gas volume flow, in which the comparisons were carried out, is from 0.5 m3/h to 50 m3/h. For the flow range from 0.5 m3/h to 1 m3/h, a drum-type meter was used, and for the range from 2 m3/h to 50 m3/h, comparisons were performed using a rotary gas meter. It is indicated that the national state primary and secondary standards of the gas volume and volume flow units took part in the comparisons from Ukraine, while from Moldova it was the national standard of the gas volume flow unit. A brief description of the national measurement standards and the principle of reproduction of the gas volume and volume flow units is presented. In particular, it was noted that the primary and secondary standards of Ukraine are built on the basis of bell-type prover, and the standard of Moldova combines a piston and bell-type prover. The method of calculating, calculation of expanded uncertainty and determining the degree of equivalence of the national standards of Ukraine and Moldova are demonstrated. The results of bilateral comparisons in the form of Table 1 are presented and shown in Fig. 4. The degree of equivalence of the national standards does not exceed 0.41, which indicates that the primary and secondary standards reproduce the gas volume and volume flow units with declared uncertainties, and transfer standards retain their metrological characteristics throughout the cycle of comparisons. General conclusions are drawn about the success of bilateral comparisons.","PeriodicalId":40775,"journal":{"name":"Ukrainian Metrological Journal","volume":null,"pages":null},"PeriodicalIF":0.1,"publicationDate":"2022-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49624065","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Redefining Standard Measurement Uncertainty 重新定义标准测量不确定度
IF 0.1
Ukrainian Metrological Journal Pub Date : 2022-03-31 DOI: 10.24027/2306-7039.1.2022.258815
A. Possolo, Olha Bodnar
{"title":"Redefining Standard Measurement Uncertainty","authors":"A. Possolo, Olha Bodnar","doi":"10.24027/2306-7039.1.2022.258815","DOIUrl":"https://doi.org/10.24027/2306-7039.1.2022.258815","url":null,"abstract":"The Guide to the Expression of Uncertainty in Measurement (GUM) defines standard measurement uncertainty as the standard deviation of a probability distribution that describes the uncertainty associated with an estimate of the measurand, and defines expanded uncertainty as a multiple of the standard uncertainty. Monte Carlo methods can produce the expanded uncertainty for 95 % coverage as one half of the length of the interval whose endpoints are the 2.5th and 97.5th percentiles of the probability distribution of the estimate of the measurand (when this distribution is approximately symmetrical). This creates an opportunity for a paradox to arise: that the standard uncertainty, defined as a standard deviation, can be larger than the expanded uncertainty. We provide an example involving real measurement data where this paradox arises with high probability, and then offer a new definition of standard uncertainty that agrees numerically with the conventional definition in “normal” cases, but that is still reliable in “abnormal” cases.","PeriodicalId":40775,"journal":{"name":"Ukrainian Metrological Journal","volume":null,"pages":null},"PeriodicalIF":0.1,"publicationDate":"2022-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46744323","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
The measurement uncertainty of air object spatial coordinates by rho-theta fixing 用rho-theta固定法测量空气物体空间坐标的不确定度
IF 0.1
Ukrainian Metrological Journal Pub Date : 2022-03-31 DOI: 10.24027/2306-7039.1.2022.258821
I. Zadorozhnaya, I. Zaharov, A. Tevyashev
{"title":"The measurement uncertainty of air object spatial coordinates by rho-theta fixing","authors":"I. Zadorozhnaya, I. Zaharov, A. Tevyashev","doi":"10.24027/2306-7039.1.2022.258821","DOIUrl":"https://doi.org/10.24027/2306-7039.1.2022.258821","url":null,"abstract":"The features of measurement uncertainty evaluation of the coordinates of an air object by the rho-theta fixing are discussed. Measurement models are presented that link its coordinates in the local rectangular coordinate system with the spherical coordinates of air object, found using a rangefinder and a goniometer. The models include a correction for determining the location of the base station, a correction for determining the angle of elevation due to inaccuracies in the leveling of the station platform and azimuth, and a correction related to the inaccuracy of the station’s reference to the north. The measurement uncertainty budgets of rectangular coordinates which can be a basis for creation of software for automation of calculation of measurement uncertainties are resulted. Estimates of expanded uncertainties are found by the method of kurtosis. Expressions for the relative standard uncertainties of coordinate measurements are written and an example of their estimation for real data is given.","PeriodicalId":40775,"journal":{"name":"Ukrainian Metrological Journal","volume":null,"pages":null},"PeriodicalIF":0.1,"publicationDate":"2022-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47285298","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
Metrological traceability chains for high DC voltage and voltages ratio 高直流电压和电压比计量溯源链
IF 0.1
Ukrainian Metrological Journal Pub Date : 2022-03-31 DOI: 10.24027/2306-7039.1.2022.258823
O. Velychko, R. Vendychanskyi
{"title":"Metrological traceability chains for high DC voltage and voltages ratio","authors":"O. Velychko, R. Vendychanskyi","doi":"10.24027/2306-7039.1.2022.258823","DOIUrl":"https://doi.org/10.24027/2306-7039.1.2022.258823","url":null,"abstract":"The current stage of scientific and technical development is characterized by the widespread use of high-voltage technology. Metrological traceability has such important elements as calibration of measurement standards and measuring instruments and evaluation of measurement uncertainty. The range of values of specific measurands, the range of necessary measurement uncertainties and the measurement standards used are presented as metrological traceability chains. Building such chains for different types of measurements is important for national metrology institutes and calibration laboratories. \u0000An urgent task is to build metrological traceability chains for high direct current voltage measuring instruments. The proposed metrological traceability hierarchy chains are used in the State Enterprise “Ukrmetrteststandard” for calibration of working standards and working measuring instruments for high DC voltage and voltages ratio. These chains can be used also by accredited calibration laboratories, which carry out calibration of working measuring instruments for high direct current voltage and voltages ratio according to their own scope of accreditation.","PeriodicalId":40775,"journal":{"name":"Ukrainian Metrological Journal","volume":null,"pages":null},"PeriodicalIF":0.1,"publicationDate":"2022-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45748902","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Methods for indirect measurements of the emissivity of tungsten and iron-carbon alloys 钨和铁碳合金发射率的间接测量方法
IF 0.1
Ukrainian Metrological Journal Pub Date : 2022-03-31 DOI: 10.24027/2306-7039.1.2022.258801
L. Zhukov, D. Petrenko
{"title":"Methods for indirect measurements of the emissivity of tungsten and iron-carbon alloys","authors":"L. Zhukov, D. Petrenko","doi":"10.24027/2306-7039.1.2022.258801","DOIUrl":"https://doi.org/10.24027/2306-7039.1.2022.258801","url":null,"abstract":"The purpose of the article is to increase accuracy and reliability of optical thermometry, including two-colour compensative thermometry with a priori averaged adjustment. The equation of nonlinearity of emissivity spectral distribution was previously obtained. The equation connects the nonlinearity coefficient of emissivity spectral distribution on the middle wave of the operating spectral range with the emissivity value at one of the boundary waves via 3 one-colour radiation temperatures. Based on the equation, linear two-range and parabolic methods for indirect measurements of emissivity is proposed. The results of emissivity determination are used to correct the a priori averaged adjustment of two-colour compensative thermometry. \u0000The linear method excludes the methodical error of temperature measurements for linear spectral distributions of emissivity. For tungsten and iron-carbon alloys, the methodical error of the two-colour compensative thermometry adjusted using the linear method does not exceed 0.52%. At the same time, the methodical errors of spectral ratio and energy pyrometry reach 3.19 and 6.07–8.42%. With a further hypothetical increase of nonlinearity coefficient by 2 times, the error of linear method increases from 0.52 to 1.02%. Both values are permissible in ferrous metallurgy. \u0000The two-range method is based on the inversion of nonlinearity of emissivity spectral distribution. The inversion means that nonlinearity coefficient changes its sign. In the case of tungsten, when spectral ranges are correctly chosen, the error of two-colour compensative thermometry with a corrected adjustment using the two-range method does not exceed the errors of reference measurements and makes up 0.06%. \u0000For essentially nonlinear distributions of emissivity, the parabolic method is proposed. The method excludes methodical error in case the emissivity on operating waves can be described by a polynomial of the 2-nd order. This polynomial approximation is typical for ferrous metals and their alloys. With the same nonlinearity of emissivity spectral distribution, for example, in case of tungsten, the error of parabolic method is 1.24 times less than of the linear method.","PeriodicalId":40775,"journal":{"name":"Ukrainian Metrological Journal","volume":null,"pages":null},"PeriodicalIF":0.1,"publicationDate":"2022-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48173846","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 2
The methods of data processing according to the measurement/classification procedure for quality indicators of objects 根据物体质量指标的测量/分类程序进行数据处理的方法
IF 0.1
Ukrainian Metrological Journal Pub Date : 2022-03-31 DOI: 10.24027/2306-7039.1.2022.258827
O.U. Hoda, Ruslana Dovgaliuk, N. Yaremchuk
{"title":"The methods of data processing according to the measurement/classification procedure for quality indicators of objects","authors":"O.U. Hoda, Ruslana Dovgaliuk, N. Yaremchuk","doi":"10.24027/2306-7039.1.2022.258827","DOIUrl":"https://doi.org/10.24027/2306-7039.1.2022.258827","url":null,"abstract":"The measurement/classification procedure of object properties, such as quality indicators, is used for determination of object quality category. According to measurement uncertainty, the fuzzy classification scale is constructed. In accordance with this scale, fuzzy classification results are obtained. The use of fuzzy averaging for multiple measurements of individual quality indicators are proposed. The fuzzy logic operators that can be used in the construction of group quality indicators are considered and recommendations for their application are given. As an example of application of the proposed method, the definition of water quality categories on its biochemical properties is used.","PeriodicalId":40775,"journal":{"name":"Ukrainian Metrological Journal","volume":null,"pages":null},"PeriodicalIF":0.1,"publicationDate":"2022-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47557927","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Energy technical light output of scintillators – problems of assessment and an alternative method for their solution 闪烁体的能量技术光输出。评估问题及其解决的替代方法
IF 0.1
Ukrainian Metrological Journal Pub Date : 2022-03-31 DOI: 10.24027/2306-7039.1.2022.258813
B. Grynyov, N. Gurdzhian, O. Zelenskaya, L. Mitcay, V. Tarasov
{"title":"Energy technical light output of scintillators – problems of assessment and an alternative method for their solution","authors":"B. Grynyov, N. Gurdzhian, O. Zelenskaya, L. Mitcay, V. Tarasov","doi":"10.24027/2306-7039.1.2022.258813","DOIUrl":"https://doi.org/10.24027/2306-7039.1.2022.258813","url":null,"abstract":"The paper analyzes the problems that arise when assessing the energy technical light output by existing methods. A modern alternative method for assessing the energy technical light output of various scintillators produced by the Institute of Scintillation Materials of the National Academy of Sciences of Ukraine is described. \u0000The possibility of evaluating the technical light output of any scintillator by relative comparison with a reference stilbene-based scintillator with a known technical light output is shown. The resulting ratio of responses is recalculated in ph/MeV by taking into account the technical light output of the reference scintillator, equal to 0.023, and the photon formation energy of a particular scintillator. \u0000The estimation procedure is described. Expressions are given for calculating the values of the technical light yield of scintillators in stilbene units and in ph/MeV. The radioluminescence spectra of the tested scintillators are compared with the sensitivity spectra of the normalized and laboratory photodetectors. \u0000The technical light yield of scintillators based on single crystals of NaI(Tl), CsI(Tl), CWO, BGO, p-terphenyl, anthracene, stilbene, and a plastic scintillator has been estimated. The values of the responses amplitudes ratio, the spectral normalization coefficients and the tested scintillators technical light output were obtained in stilbene units and in ph/MeV. To check the adequacy of the method the calculation of the tested inorganic scintillators absolute light output was carried out using the light collection coefficients values given in the literature. \u0000It is shown that with an increase in the scintillators technical light output, in stilbene units, from 0.26 for BGO to 4.3 for NaI(Tl), their technical light output increases from 2500 ph/MeV to 33100 ph/MeV. A decrease in the scintillation photon energy from 2.988 (l = 415 nm) for NaI(Tl) to 2.214 (l = 560 nm) for CsI(Tl) also increases the technical light output of the latter to 35300 ph/MeV. The performed estimates accuracy of scintillators technical light output was 8%.","PeriodicalId":40775,"journal":{"name":"Ukrainian Metrological Journal","volume":null,"pages":null},"PeriodicalIF":0.1,"publicationDate":"2022-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68826405","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Experimental investigation on the effective radiating area of ultrasonic transducers with the aim of increasing the reproduction accuracy of the unit of ultrasonic pressure in water 以提高水中超声压力单元再现精度为目的,对超声换能器有效辐射面积进行了实验研究
IF 0.1
Ukrainian Metrological Journal Pub Date : 2022-03-31 DOI: 10.24027/2306-7039.1.2022.258819
O. Shpak, Dariia Duviriak, V. Parakuda, I. Kizlivskyi
{"title":"Experimental investigation on the effective radiating area of ultrasonic transducers with the aim of increasing the reproduction accuracy of the unit of ultrasonic pressure in water","authors":"O. Shpak, Dariia Duviriak, V. Parakuda, I. Kizlivskyi","doi":"10.24027/2306-7039.1.2022.258819","DOIUrl":"https://doi.org/10.24027/2306-7039.1.2022.258819","url":null,"abstract":"This paper presents the results of an experimental investigation on the effective radiating areas (AER) of auxiliary ultrasonic transducers forming part of the measurement standard for the unit of ultrasonic pressure in water NDETU AUV-02-2018. When carrying out measurements, the pressure field of MANA Instruments ultrasonic transducers E1025-SU; E2312-SU; E3512-SМ has been subjected to raster scanning at operating frequencies using a raster scanning system. A positioning device for ultrasonic transducers was developed at DP NDI “Systema” in the process of creating the measurement standard NDETU AUV-02-2018, and forms its integral part. The AER calculation protocol has been developed based on IEC 61689. The type A uncertainty has been evaluated from ten repetitions of the full measurement procedure to determine the AER, аnd the type B uncertainty has been estimated from the AER-specific mathematical model based on IEC 61689 and DSTU-N RMG 43 “Metrology. Application of the Guide to the Expression of Uncertainty in Measurement”.","PeriodicalId":40775,"journal":{"name":"Ukrainian Metrological Journal","volume":null,"pages":null},"PeriodicalIF":0.1,"publicationDate":"2022-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42972962","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
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
Ukrainian Metrological Journal Pub Date : 2022-03-31 DOI: 10.24027/2306-7039.1.2022.258818
V. Witkovský
{"title":"Implementation of the characteristic functions approach to measurement uncertainty evaluation","authors":"V. Witkovský","doi":"10.24027/2306-7039.1.2022.258818","DOIUrl":"https://doi.org/10.24027/2306-7039.1.2022.258818","url":null,"abstract":"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).","PeriodicalId":40775,"journal":{"name":"Ukrainian Metrological Journal","volume":null,"pages":null},"PeriodicalIF":0.1,"publicationDate":"2022-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41762422","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
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