数显测高仪示值误差的测量不确定度评定

针对数显测高仪各校准点示值误差的校准方法,给出了示值误差的数学模型,并以某校准点为例,对该校准点示值误差的合成标准不确定度和扩展不确定度进行了评定.     

光散射式粉尘浓度测定仪示值误差测得值不确定度的评定

依据JJG 846-2015《粉尘浓度测量仪检定规程》及JJF 1059.1-2012《测量不确定度评定与表示》,对光散射原理仪器按规程要求的各校准点示值误差测得值不确定度进行了评定,评定过程真实有效,可为相关机构技术人员在检定/校准光散射式粉尘浓度测量仪中评定示值误差测得值的不确定度提供参考。     

化学需氧量(COD)测定仪示值误差测得值不确定度的评定

依据JJG 975-2002《化学需氧量(COD)测定仪检定规程》及JJF 1059.1-2012《测量不确定度的评定与表示》对分光光度原理A类仪器及电化学原理B类仪器,按规程要求各校准点示值误差测得值不确定度进行了评定,评定过程真实有效,可为相关机构技术人员在检定/校准化学需氧量测定仪中评定示值误差测得值的不确定度提供参考.     

建筑工程质量检测器组示值误差测量结果不确定度分析报告

<正>建筑工程质量检测器组示值误差测量结果不确定度分析依据了JJF 1110—2003《建筑工程质量检测器组校准规范》,以建筑工程质量检测器标准装置为计量标准,被测对象为垂直度检测尺。测量方法是将垂直度检测尺安装在校准装置上,均匀选择5个校准点,依次旋转测量头,读数值减去标准值即为相应点的示值误差。     

无线压力记录器校准及其测量不确定度评定

详细分析了无线压力记录器示值误差的校准方法及其不确定度来源,并以MPⅢ型压力记录器为例,遵从JJF 1059.1-2012《测量不确定度评定与表示》所推荐的评估方法,评定以0.05级数字压力计为标准器校准压力记录器时示值误差的扩展不确定度,为数字压力计校准无线压力记录器时示值误差的不确定评定提供了范例.     

电子天平示值误差的测量结果不确定度

本文分析了用E2等级砝码校准电子天平所得示值误差的测量结果不确定度,介绍了校准电子天平示值误差测量结果不确定度的评定步骤和方法,给出了判定结果。     

自动标准压力发生器示值误差的测量不确定度研究

使用0.005级气体活塞式压力计对0.02级自动标准压力发生器进行校准。阐述了自动标准压力发生器示值误差的测量的不确定度评定方法,提出了示值重复性和分辨率引入的不确定度分量应取其中较大者,感压面高度差引入的不确定度分量应考虑压力变化对气体传压介质密度的影响;分析了合成不确定度中各分量的权重:标准器引入的不确定度分量为主要的合成不确定度来源,随着校准点压力值的增加,重复性/分辨力引入的不确定度分量权重显著减小,感压面高度差引入的不确定度分量权重在400kPa校准点以上,超过重复性/分辨力成为仅次于标准器的合成不确定度来源。     

光栅测长机示值误差的不确定度评定

依据测长机示值误差的校准方法,本文对量块校准时光栅测长机示值误差的误差来源分析并对其不确定度进行评定,为光栅测长机使用和校准中示值误差影响因素的分析提供了技术支持与帮助。     

垂直轴偏差测量仪的校准及示值误差的不确定度评定

根据垂直轴偏差测量仪的应用需求,提出了一种用专用圆柱直角尺校准垂直轴偏差测量仪示值误差的校准方法,并进行了示值误差的测量不确定度评定。结果表明,该方法校准垂直轴偏差测量仪的扩展不确定度满足使用要求。     

电子天平示值误差测量值的不确定度计算器的开发

本文对电子天平示值误差测量值的不确定度进行分析评定,利用软件开发不确定度计算器,简化校准电子天平时计算示值误差测量值的不确定度的计算问题。     

Estimation of Parameters of Universal Distribution of Moments of Failure of Products

A method is proposed for estimating the parameters of a mixture of exponential and Weibull distributions for which the accuracy of preliminary estimates obtained by graphical analysis is refined in accordance with the criterion of maximum likelihood. The efficiency of the proposed method is supported by the results of statistical modeling.     

Analysis of the rate of propagation of the wave of change of boiling modes

An approximate analytical expression is derived for the velocity of the front of the wave of change of boiling modes on a rod and on a plate. The impact of the Thomson effect and of the heater orientation in the gravity field is included. Adequate agreement is demonstrated between the derived relations and experimental data.     

Evaluation of optical properties of highly scattering media by moments of distributions of times of flight of photons

A novel method for the determination of the optical properties of tissue from time-domain measurements is presented. The data analysis is based on the evaluation of the first moment and the second centralized moment, i.e., the mean time of flight and the variance of the measured distribution of times of flight (DTOF) of photons injected by short (picosecond) laser pulses. Analytical expressions are derived for calculation of absorption and of reduced scattering coefficients from these moments by application of diffusion theory for infinite and semi-infinite homogeneous media. The proposed method was tested on experimental data obtained with phantoms, and results for absorption and reduced scattering coefficients obtained by the proposed method are compared with those obtained by fitting of the same data with analytical solutions of the diffusion equation. Furthermore, the accuracy of the moment analysis was investigated for a range of integration limits of the DTOF. The moment analysis may serve as a comparatively fast method for evaluating optical properties with sufficient accuracy and can be used, e.g., for on-line monitoring of optical properties of biological tissue.     

可燃气体检测报警器测量结果的不确定度评定

本文详细介绍了可燃气体检测报警器示值误差测量结果的不确定度评定方法。     

水三相点复现的不确定度评定

水三相点是开尔文热力学温度的唯一基准点，也是ITS-90国际温标重要的定义固定点。因此，水三相点不确定度分析对整个温标的建立、温度量值传递起着至关重要的作用。近3年来，中国计量科学研究院研制出一系列高质量的水三相点容器，加强了水三相点的研究，为不确定度的分析提供了更为可靠的实验依据。同时，不确定度的分析也是客观评价新研制容器性能的一个重要指标。因此，根据实验结果对新研制容器所复现的水三相点进行了不确定度评定。评定结果表明，其扩展不确定度为0．16mK(k=2．69，P=0．99)。     

心电图机电压测量示值误差测量值的不确定度评定

本文介绍了心电图机电压测量示值误差测量值的不确定度评定与表示方法。     

Estimation of potentialities of methods of summation of direct measurement errors

Conventional methods for summation of direct measurement errors are considered. Conditions under which these methods provide consistent results are stated. It is proposed to utilize for characteristic of the total error, its interval estimator or the half-sum of the value obtained by adding up its arithmetic and geometric random errors.Translated from Izmeritel'naya Tekhnika, No. 4, pp. 10–12, April, 1995.