瓦楞包装纸关键项目测量结果不确定度的评定

根据不确定度评定的通用规则,以瓦楞原纸纵向抗张强度为例,分析了瓦楞包装纸关键项目测量结果不确定度的来源,并对关键项目的测量不确定度进行了评定,找到了影响测量结果不确定度的关键因素。     

国产原纸环压强度与瓦楞纸板、纸箱抗压强度之间关系的研究

通过对国产瓦楞原纸、箱纸板环压强度、瓦楞纸板边压强度和纸箱抗压强度的测试、分析和研究 ,导出了国产原纸、瓦楞纸板、纸箱耐压强度之间的关系公式 ,提出了瓦楞纸板边压强度修正系数 fw及通过其和原纸环压强度来估算瓦楞纸板边压强度、纸箱抗压强度的方法。     

纸板厚度测量不确定度的评定

本文按照纸板厚度试验的基本要求,对瓦楞原纸厚度测量中的不确定度进行了评定。结果表明,仪器设备的精度对厚度测量结果影响较大;此外,当测量次数减少对结果的影响在允许范围之内,实验室待测纸样有限的情况下,可适当减少厚度测量的取样量。     

瓦楞纸箱边压强度的不确定度分析

根据JJF 1059.1—2012《测量不确定度评定与表示》,分析了纸箱边压强度不确定度的主要来源并对其量化,同时对纸箱边压强度不确定度进行了评定。结果表明,影响不确定度的主要因素是重复性测量、仪器的示值误差、数值修约。这批瓦楞纸箱测量结果及不确定度U=(8.94±0.23)×103N/m,k=2。     

瓦楞纸板边压强度测定不确定度的评定

本文根据JJF 1059-1999<测量不确定度评定与表示>,对引起瓦楞纸板边压强度测定的不确定度来源进行了分析和量化,对瓦楞纸板边压强度的测定的不确定度进行了评定.     

瓦楞纸板边压强度影响因素分析

目的分析瓦楞纸板边压强度与其基本物理参数之间的关系。方法通过试验测量不同弹性模量、泊松比的原纸所对应不同结构参数的瓦楞纸板的边压强度。结果当材料一定时,原纸的定量越大,厚度越厚;原纸的纵向弹性模量总是大于横向弹性模量;相同类型的原纸随着定量的增大,其纵横向弹性模量和剪切模量逐渐增大;面纸定量相同、芯纸定量不同的瓦楞纸板,其边压强度随芯纸定量增大而增大;芯纸定量相同、面纸定量不同的瓦楞纸板,其边压强度随面纸定量增大而增大;材质相同、楞形不同的瓦楞纸板,其边压强度由大到小依次为A型、C型、B型。结论瓦楞原纸物性参数、瓦楞纸板结构参数均对瓦楞纸板边压强度有决定性的影响。     

聚氨酯防水涂料拉伸强度测量不确定度的评定

通过相关国家计量规程对聚氨酯防水涂料拉伸强度的测量不确定度进行评定,找出影响拉伸强度检测结果的主要因素,对力学检测领域测量不确定度的评定具有借鉴意义。     

钢筋抗拉强度测量结果的不确定度评定

用微机控制电液伺服式万能试验机测量钢筋的抗拉强度时,为确定测量结果的分散性即测量结果的置信区间,对影响检测结果的诸多因素进行分析,确定不确定度产生的来源,并采用A类不确定度评定和B类不确定度评定的方法,对各个不确定度分量进行评定,再根据各个量的方差和协方差算得合成标准不确定度,最终用扩展不确定表示,给出钢筋抗拉强度测量的不确定度报告。     

滤毒罐通气阻力测量结果不确定度评定

对某型滤毒罐通气阻力检测结果进行了不确定度评定,对其检测的装置、测量重复性、温度、大气压、测量系数等引入的不确定度进行了评定,得出了某型滤毒罐阻力检测结果的扩展不确定度为5.28Pa。     

AB型瓦楞纸箱边压强度测量不确定度评估

根据GB/T 6546-1998,对一批AB型瓦楞纸箱进行边压强度的测试,并根据标准JJF 1059-1999对其进行了不确定度的评估。其不确定度主要来源是重复性测量、仪器自身示值准确度、数值修约。这批AB型瓦楞纸箱边压强度测量扩展不确定度为78.26 N。     

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.