Ukrainian Metrological Journal最新文献

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Efficiency of diagnosing the condition of rolling bearings in real time 实时诊断滚动轴承状态的效率
IF 0.1
Ukrainian Metrological Journal Pub Date : 2022-12-29 DOI: 10.24027/2306-7039.4.2022.276322
T. Barashkova, Veroonika Shirokova
{"title":"Efficiency of diagnosing the condition of rolling bearings in real time","authors":"T. Barashkova, Veroonika Shirokova","doi":"10.24027/2306-7039.4.2022.276322","DOIUrl":"https://doi.org/10.24027/2306-7039.4.2022.276322","url":null,"abstract":"One of the control elements of a complex technological system is an information-and-measuring network, a significant part of which is represented by measuring transducers and sensors. Due to the design features, the sensors turn out to be unreliable elements of information-and-measuring systems. Distortions in sensor readings affect the quality of controlling the technical system. It is necessary to account for these distortions when assessing the efficiency of the diagnostics of mechanical components. This fact is especially significant when assessing the efficiency of diagnosing the condition of rolling bearings in real time. \u0000It is proved that the efficiency of diagnosing the machine parts largely depends on the dynamics of the information-and-measuring system and the prompt detection of changes in the operation of this system. As a result of the experiments, the primary task to diagnose the machine parts was solved on the example of faulty rolling bearings, and the influence of the computing power of the equipment used, the sensitivity of the acceleration sensors, and practical feasibility of the network algorithms for automatic data processing in real time were assessed.","PeriodicalId":40775,"journal":{"name":"Ukrainian Metrological Journal","volume":null,"pages":null},"PeriodicalIF":0.1,"publicationDate":"2022-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48339257","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
Analysis and comparison of Bayesian methods for type A uncertainty evaluation with prior knowledge 基于先验知识的A类不确定度贝叶斯评价方法的分析与比较
IF 0.1
Ukrainian Metrological Journal Pub Date : 2022-12-29 DOI: 10.24027/2306-7039.4.2022.276284
I. Lira
{"title":"Analysis and comparison of Bayesian methods for type A uncertainty evaluation with prior knowledge","authors":"I. Lira","doi":"10.24027/2306-7039.4.2022.276284","DOIUrl":"https://doi.org/10.24027/2306-7039.4.2022.276284","url":null,"abstract":"If a number of observations about a certain quantity may be assumed independent, drawn from a Gaussian distribution, Supplement 1 to the GUM recommends that the standard uncertainty associated with the quantity be obtained by a formula that is applied to more than three observations. Various articles have recently appeared proposing Bayesian methods to surmount this limitation. Some of these methods, which require prior knowledge about the quantity, are reviewed in this article.","PeriodicalId":40775,"journal":{"name":"Ukrainian Metrological Journal","volume":null,"pages":null},"PeriodicalIF":0.1,"publicationDate":"2022-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49084325","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
Metrological aspects of introducing charging stations for electric vehicles 引入电动汽车充电站的计量方面
IF 0.1
Ukrainian Metrological Journal Pub Date : 2022-09-30 DOI: 10.24027/2306-7039.3.2022.269704
O. Velychko, T. Gordiyenko
{"title":"Metrological aspects of introducing charging stations for electric vehicles","authors":"O. Velychko, T. Gordiyenko","doi":"10.24027/2306-7039.3.2022.269704","DOIUrl":"https://doi.org/10.24027/2306-7039.3.2022.269704","url":null,"abstract":"Electric mobility is a rapidly evolving field, so electricity is considered one of the main alternative fuels. Electricity is a particularly attractive source of energy, which is used for electric vehicles (EVs) in urban/suburban agglomerations and other densely populated areas. An extensive network of EV charging stations is a major factor for using electric vehicles. \u0000The main method of EV charging is to connect the on-board charger to the AC power supply. An alternative method of EV charging is to connect the outboard charger to the DC power supply. There are three main options to connect an EV to a charging station: using a special power cable; with a pantograph; via wirelesses connection. A standardized interface between the electric vehicle and infrastructure seems to be one of the most topical challenges in the world of electric mobility. \u0000International standards cover payment accounting systems for electricity and provide specifications on the equipment and protocols for meter data exchange. There is an urgent need to draw up national or regional metrological regulations for EV charging. The issue of international and regional standardization of DC electricity meters for using at charging stations remains pressing.","PeriodicalId":40775,"journal":{"name":"Ukrainian Metrological Journal","volume":null,"pages":null},"PeriodicalIF":0.1,"publicationDate":"2022-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48511410","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
Analysis of hot coolants of nuclear power plants by sonoluminescence spectroscopy 用声致发光光谱法分析核电站热冷却剂
IF 0.1
Ukrainian Metrological Journal Pub Date : 2022-09-30 DOI: 10.24027/2306-7039.3.2022.269796
O. Yurchenko, Tetiana Chernozhuk, Oleksandr Baklanov
{"title":"Analysis of hot coolants of nuclear power plants by sonoluminescence spectroscopy","authors":"O. Yurchenko, Tetiana Chernozhuk, Oleksandr Baklanov","doi":"10.24027/2306-7039.3.2022.269796","DOIUrl":"https://doi.org/10.24027/2306-7039.3.2022.269796","url":null,"abstract":"The use of sonoluminescence spectroscopy to analyse hot salt coolants of nuclear power plants, such as caesium and lithium chlorides, was studied. The influence of temperature on the intensity of sonoluminescence of caesium and lithium was experimentally tested. At the same time, with increasing temperature of the solution, the intensity of sonoluminescence of caesium decreased slightly and reached its minimum value at a temperature of 80–82 °C and then increased, reaching its maximum possible value at a temperature of 97–100 °C and decreased again. The intensity of sonoluminescence of lithium also decreased with decreasing temperature of the solution, but this decrease was less significant than that of caesium. The study of the influence of temperature on the results of the determination of the main substance in solutions of salt coolants showed the possibility of accurate determination of the content of caesium and lithium in salt coolants up to a temperature of 150 °C. To achieve better metrological characteristics of the analysis results, ultrahigh-frequency ultrasound with a frequency of 10−12 MHz at an intensity of 20 W∕cm2 should be used to initiate sonoluminescence. A method of determining the content of the main substance in solutions of salt coolants of NPP has been developed. The correctness of the technique was verified by the method of standard additives, as well as by the analysis of coolant samples with different contents of the main substance. At the same time, the value of the relative standard deviation of the results of the determination of the content of lithium chloride (400 g∕l) was 0.076−0.084, and the determination of the content of caesium chloride (600 g∕l) was 0.060−0.069.","PeriodicalId":40775,"journal":{"name":"Ukrainian Metrological Journal","volume":null,"pages":null},"PeriodicalIF":0.1,"publicationDate":"2022-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46483543","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
Luminance flicker of LED lamps and lighting fittings for general lighting 普通照明用LED灯和照明配件的亮度闪烁
IF 0.1
Ukrainian Metrological Journal Pub Date : 2022-09-30 DOI: 10.24027/2306-7039.3.2022.269747
P. Neyezhmakov, Oleksandr Pitiakov, S. Shpak, Sabir Baghirov, Tamara Sakhno, G. Kozhushko
{"title":"Luminance flicker of LED lamps and lighting fittings for general lighting","authors":"P. Neyezhmakov, Oleksandr Pitiakov, S. Shpak, Sabir Baghirov, Tamara Sakhno, G. Kozhushko","doi":"10.24027/2306-7039.3.2022.269747","DOIUrl":"https://doi.org/10.24027/2306-7039.3.2022.269747","url":null,"abstract":"The results of the studies of the impact of luminance flicker of light sources powered by an alternating current network on the well-being and health of people, the peculiarities of the flicker of LED lighting installations and recommendations on the safe level of luminance flicker of lamps and lighting fittings for general lighting are analysed. The paper also considers modern methods of evaluating flicker parameters, which are recommended by international standards. \u0000The luminance flicker of commercial samples of LED lamps and lamps that are being introduced to the lighting market from various manufacturers of LED products was studied. \u0000Measurements of the depth of luminance modulation and flicker index in the frequency range up to 3 kHz in accordance with the recommendations of the IEEE 1789:2015 standard were carried out. Measurements of the short-term modulation dose in accordance with the IES/TR 61547-1:2017 international standard were carried out. Measurements of the visibility indicator of the stroboscopic effect in accordance with the recommendations of the IES/TR 63518:2018 standard were carried out. The MK350S spectroradiometer with software for calculating photometric and colorimetric parameters, as well as the flicker and stroboscopic effect parameters, was used. It was found out that LED products for general lighting that are being introduced to the Ukrainian lighting market mainly have a safe level of luminance flicker. The level of luminance flicker of modern LED lamps and lighting fittings is lower than that of any other light sources powered by an alternating current network, including discharge lamps with high-frequency electronic ballasts. It was concluded that the requirements for the limit levels of flicker for various frequency ranges and methods of measuring flicker parameters should be included in the regulatory documents on LED products for general lighting.","PeriodicalId":40775,"journal":{"name":"Ukrainian Metrological Journal","volume":null,"pages":null},"PeriodicalIF":0.1,"publicationDate":"2022-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48065074","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
Uncertainty in case of lack of information: extrapolating data over time, with examples of climate forecast models 在缺乏信息的情况下的不确定性:利用气候预报模式的例子,随着时间的推移推断数据
IF 0.1
Ukrainian Metrological Journal Pub Date : 2022-09-30 DOI: 10.24027/2306-7039.3.2022.269537
F. Pavese
{"title":"Uncertainty in case of lack of information: extrapolating data over time, with examples of climate forecast models","authors":"F. Pavese","doi":"10.24027/2306-7039.3.2022.269537","DOIUrl":"https://doi.org/10.24027/2306-7039.3.2022.269537","url":null,"abstract":"The basic scientific tool for predicting is called a “forecast model”, a mathematical model underpinned by observations. Generally, it is the evolution of some parameters of the present-day law(s) over time that are considered of fundamental importance in a specific case. The relevant available data are obviously limited to the past period of time, which is admittedly a limited period in most cases, when the law in question is considered valid and verified with sufficient precision − while no direct information is available about the future trend. A mathematical (set of) function(s) is extrapolated ahead over time to show present and next generations what they should be supposed to observe in the future. A problem arises from the fact that no (set of) mathematical function that could be used for a model is infinitely “flexible”, i.e. apt to “correctly” interpolate any cluster of data, and the less a data set is, the less the parameters of the function(s) are. A data consistency is considered good when there is a balance between a mere “copying” the behaviour over time (e.g. when a function has to follow a given profile) and a satisfactory “averaging” the behaviour, especially over longer periods of time, without “masking” changing points. Furthermore, the data uncertainty is an embellishment, which the information often lacks, provided with extrapolations. Instead of it, the data uncertainty must be taken into account, and appropriate information must always be provided, since the quality of the adjustment of the available data is crucial for the quality of the subsequent extrapolation. Therefore, the forecast should better consist of an area (typically increasing its width over time) where future determinations are assumed to fall within a given probability range. Thus, it should be perfectly clear that the extrapolation of the past data into the future, i.e. a current evaluation that can be propagated to next generations, is affected by a high risk and that careful precautions and limitations should be taken.","PeriodicalId":40775,"journal":{"name":"Ukrainian Metrological Journal","volume":null,"pages":null},"PeriodicalIF":0.1,"publicationDate":"2022-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46293179","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
Applying covariance analysis to determine the factor influence on the control parameter in colorimetric study 应用协方差分析确定色度研究中控制参数的影响因素
IF 0.1
Ukrainian Metrological Journal Pub Date : 2022-09-30 DOI: 10.24027/2306-7039.3.2022.269783
Serhii Yefymenko, Ihor Hryhorenko, Iurii Khoroshailo, S. Hryhorenko
{"title":"Applying covariance analysis to determine the factor influence on the control parameter in colorimetric study","authors":"Serhii Yefymenko, Ihor Hryhorenko, Iurii Khoroshailo, S. Hryhorenko","doi":"10.24027/2306-7039.3.2022.269783","DOIUrl":"https://doi.org/10.24027/2306-7039.3.2022.269783","url":null,"abstract":"The paper considers solutions to a scientific and practical problem of applying covariance analysis to determine the factor influence on the functional transformation of the control parameter in colorimetric study. The study implies determining the factor influence on the additive and multiplicative components of the measurement error of the colorimetric control parameter to assess the validity of conclusions about the factor influence on the transformation of the control parameter. The limitations on the number of basic levels (control parameters) and the factors influencing the result of colorimetric control are determined. During the study, the equations to assess the validity of statistical conclusions about the informational significance of the colorimetric control indicators for a simplified model of cross-classification were obtained. \u0000The need for the study is due to the fact that in colorimetric control of cereal grains, the measurement uncertainty of the results of measuring the values of the controlled indicators at given levels of the control parameter is quite high. \u0000In modern industry, colorimetry has a number of advantages over other methods, such as weight analysis. Colorimetric determinations are performed much faster. In the case of weight analysis, the chemical reaction is at the beginning of the determination followed by a series of long operations, while in the case of colorimetry, the colors are compared immediately after the chemical reaction. Therefore, the colorimetric method belongs to the methods of express control. \u0000The main task of colorimetric express control (in our case) is to determine the quality of cereal grains. The task is important and relevant because grain, namely flour, is the main ingredient of many foods, e.g. bread, pasta, pastries, and cookies. Quality products can be obtained only from quality raw materials. Thus, at present time, it is relevant to determine the quality of cereal grains, and flour as the derived product, in Ukraine.","PeriodicalId":40775,"journal":{"name":"Ukrainian Metrological Journal","volume":null,"pages":null},"PeriodicalIF":0.1,"publicationDate":"2022-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41543275","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
Ways to increase the reliability and accuracy of determining the geometric parameters of cracks in the concrete of buildings using the ultrasonic pulse method 探讨了如何提高超声脉冲法测定建筑物混凝土裂缝几何参数的可靠性和准确性
IF 0.1
Ukrainian Metrological Journal Pub Date : 2022-09-30 DOI: 10.24027/2306-7039.3.2022.269732
Y. Serikov
{"title":"Ways to increase the reliability and accuracy of determining the geometric parameters of cracks in the concrete of buildings using the ultrasonic pulse method","authors":"Y. Serikov","doi":"10.24027/2306-7039.3.2022.269732","DOIUrl":"https://doi.org/10.24027/2306-7039.3.2022.269732","url":null,"abstract":"During the exploitation of buildings, cracks appear in the concrete of structural elements, which can reduce the physical and mechanical characteristics of their structures. With a certain exposure width and depth, cracks are subject to filling with special materials. In case of error in determining the crack depth, the repair material may not fill it sufficiently. This might lead to accidents. Nowadays, the most common method is to measure the parameters of cracks with a microscope and a measuring probe. Its disadvantage underlies in insufficient reliability of the crack depth measurement. This is because if there is an internal lintel of concrete residues in the crack, there may be an error in measuring its depth. The ultrasonic pulse method is also used, when the depth of the crack is determined by the time of travel of ultrasonic vibrations on the section of high-quality concrete and on the section with a crack. This method is not very reliable because the ultrasonic vibrations can also propagate through the internal lintel of the concrete residues in the crack. In this case, the measurement result will be false. An improved ultrasonic pulse method is used when the combined amplitude of the information signal is also measured. The use of this parameter is insufficient because solving the problem requires taking into account spectral characteristics of the parameter. At the stage of development, there is a method that uses surface ultrasonic waves. Its disadvantages are relative complexity of research in concrete and high cost of equipment. To increase the reliability and accuracy of determining the geometric parameters of cracks in concrete, studies were carried out using a complex ultrasonic pulse method. During the research, the value of the normalized propagation time of ultrasonic vibrations, the amplitude, and duration of the first half-period of the information signal were measured. The results of the research allow us to recommend the developed method for solving the problem.","PeriodicalId":40775,"journal":{"name":"Ukrainian Metrological Journal","volume":null,"pages":null},"PeriodicalIF":0.1,"publicationDate":"2022-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48395047","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
Express method for measuring the refractive index of transparent fibres 透明纤维折射率的快速测量方法
IF 0.1
Ukrainian Metrological Journal Pub Date : 2022-09-30 DOI: 10.24027/2306-7039.3.2022.269771
Mykola Kokodii, A. Natarova, I. Priz, O. Biesova
{"title":"Express method for measuring the refractive index of transparent fibres","authors":"Mykola Kokodii, A. Natarova, I. Priz, O. Biesova","doi":"10.24027/2306-7039.3.2022.269771","DOIUrl":"https://doi.org/10.24027/2306-7039.3.2022.269771","url":null,"abstract":"An express method for measuring the refractive index, which is one of the main optical parameters of transparent fibres, is suggested. The method uses focusing properties of a cylindrical lens, which such a fibre is. The possibility to accurately measure such characteristics of optical fibres as the shell and core diameters, numerical aperture, refractive index profile, loss, and dispersion is equally important for fibre manufacturers and designers of optical communication systems who should choose the fibre that meets their requirements best. Almost all measurement methods use the refraction of light rays at the interface between the media. To do this, one should make samples of given shape and size, which are individual for each measuring instrument. The suggested method takes into account the fact that when light strikes upon a refractive cylinder (glass rod, fibreglass), the focusing occurs perpendicular to its axis with a focal region where light rays converge. Behind this region, the rays diverge again. The position of the focal region is determined by the refractive index of the cylinder. It can be inside the cylinder, outside it, or on the surface of the cylinder. During the observation of the fibre using a microscope, one can see that the light, which has passed through the fibre, forms a bright band on its backside against a dark background. The bandwidth depends on the refractive index of the fibre. The calculations using the methods of geometric optics were carried out. These methods may be applied over a wide range of fibre diameters. Using strict formulas of diffraction theory, the distribution of radiation energy in the fibre and its vicinity was calculated. A digital analysis of the resulting pattern was carried out. The results of the analysis coincided with the results obtained using the methods of geometric optics. An algorithm for determining the refractive index was worked out. The measurements of the refractive indices of artificial and natural fibres like fibreglass, webs and human hair (blonde-haired person, brown-haired person, grey hair) were provided.","PeriodicalId":40775,"journal":{"name":"Ukrainian Metrological Journal","volume":null,"pages":null},"PeriodicalIF":0.1,"publicationDate":"2022-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45292058","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
Evaluation of the measurement uncertainty during the calibration of teraohmmeters and insulation resistance meters 太赫兹计和绝缘电阻计校准过程中测量不确定度的评定
IF 0.1
Ukrainian Metrological Journal Pub Date : 2022-09-30 DOI: 10.24027/2306-7039.3.2022.269718
M. Serhiienko, I. Skrypka, Natalya Shtefan
{"title":"Evaluation of the measurement uncertainty during the calibration of teraohmmeters and insulation resistance meters","authors":"M. Serhiienko, I. Skrypka, Natalya Shtefan","doi":"10.24027/2306-7039.3.2022.269718","DOIUrl":"https://doi.org/10.24027/2306-7039.3.2022.269718","url":null,"abstract":"When preparing for accreditation, testing and calibration laboratories face the problem of developing methods for evaluating the measurement uncertainty. The interpretation of the Guide to the Expression of Uncertainty in Measurement regarding the calibration is given in the document of the European Cooperation for Accreditation. Despite the availability of guidance documents and publications on this issue, each evaluation case requires an analysis. \u0000The paper considers the calibration of teraohmmeters and insulation resistance meters, the feature of which is the lack of appropriate high resistance measures. Therefore, a resistance Y-network is used, which allows generating the reference resistance using three measures, which in turn causes additional components of the uncertainty. The analysis of the uncertainty components and the sensitivity coefficients of the deviation of indications to input values is conducted. The evaluation of the combined standard uncertainty and the expanded measurement uncertainty of the deviation of the calibration object indications is carried out, and the uncertainty budget is provided. An example of applying the developed method is given.","PeriodicalId":40775,"journal":{"name":"Ukrainian Metrological Journal","volume":null,"pages":null},"PeriodicalIF":0.1,"publicationDate":"2022-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46063833","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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