扭矩扳子检定装置测量不确定度评定

结合扭矩扳子检定装置的建标工作,依据JJG707-2003《扭矩扳子检定规程》、GJB2749A-2009《军事计量测量标准建立与保持通用要求》、GJB3756-99《测量不确定度表示及评定》,对扭矩扳子检定装置的测量标准不确定度以及利用该装置检定4级扭矩扳子的测量结果不确定度进行了评定。     

扭矩扳子检定装置测量不确定度评定

本文介绍了用扭矩扳子检定装置对扭矩扳子示值误差进行检定的测量不确定度的评定过程。     

扭矩扳子示值误差的测量结果不确定度评定

通过使用扭矩扳子检定装置对准确度等级为1级的数显式扭矩扳子进行检定校准,提出了扭矩扳子示值误差的测量,结果不确定度的影响量,并给出了测量结果不确定度的评定和计算方法。     

扭矩扳子示值误差的测量结果不确定度

本文就本所的扭矩扳子检定仪,结合JJG707-2003《扭矩扳子检定规程》的要求,对扭矩扳子示值误差测量结果的不确定度进行评定。     

数字式扭矩扳子校准值的测量不确定度评定

本文主要通过GNJ30扭矩扳子检定仪对CNB50数字式扭矩扳子30Nm量值点测量所得校准值的不确定度分析和评定为例,介绍了数字式扭矩扳子测量结果的不确定度评定方法。     

扭矩扳手示值误差测量不确定度评定

依据JJG707-2014《扭矩扳子》检定规程和JJF1059.1-2012《测量不确定度评定与表示》,结合实际校准工作,对扭矩扳子测量值的不确定评定具有参考意义。     

扭矩扳子检定仪示值误差测得值不确定评定

本文介绍了扭矩扳子检定仪示值误差测得值不确定度的评定与表示。     

数字式扭矩扳手测量结果的不确定度评定

本文阐述了数字式扭矩扳子检定仪测量结果的不确定度评定方法和步骤。     

扭矩板子测量结果的不确定度评定

本文结合检定工作实际经验,提出了对扭矩扳子测量结果的不确定度评定方法。     

数字式扭矩扳子检定装置示值不确定度的评定

文章介绍DOTE50N3数字式扭矩扳子检定仪的工作原理、技术指标,并对其作为扭矩扳子检定装置示值的不确定度进行分析.     

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.     

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.     

Assessment of intakes of mixtures of radionuclides

Australia has several uranium mines and a large number of mineral sand mines, with associated processing facilities. Exposures resulting from these mining and processing operations usually involve intakes of mixtures of radionuclides. This work describes the development of a suite of first order, linear compartment models, based on the ICRP Publication 66 respiratory tract model, and an analytical solution to the decay equations, for assessing the consequences of such intakes. The computer programs based on these models directly compute excretion, organ retention and organ and whole-body doses for intakes of either single radionuclides or any mixture of radionuclides belonging to the same radioactive decay chain. The intake can be via inhalation, ingestion or injection, and can be acute, chronic or of limited duration. The starting concentration and degree of secular (dis)equilibrium can be specified for each radionuclide. No assumptions need to be made about the relative magnitudes of the radioactive half-lives of the different nuclides.     

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.     

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.     

空压机轴承箱蜗壳温度探头油封改造

由于空压机进气侧轴承箱蜗壳温度探头密封效果不好,使空压机及其后续管道受到油污染。后将温度探头的O形圈密封改为骨架油封,杜绝了轴承箱漏油问题。文章简介空压机的结构和技术参数,详细介绍了骨架油封的制作和优点。     

Determination of parameters of microstructural inhomogeneity of deformation of metals by the method of modeling

The article suggests a method of evaluating the microstructural inhomogeneity of deformation of metals by modeling. The method includes the measurement of deformations of metal according to meshes of a dividing grid with small base and the calculation of the distribution parameters of microdeformations in model representation. It is shown that the modeling method makes it possible objectively to evaluate the microinhomogeneity of deformation of metals independently of the chosen mesh size of the dividing grid. New structural characteristics are introduced: the base and wave of variation expressing the degree of crumbling or amalgamation of metal grains by inhomogeneity of deformation.Translated from Problemy Prochnosti, No. 7, pp. 40–44, July, 1991.     

Characteristics of mechanical properties of materials in studies of conditions of attainment of marginal states

It is shown that conditions of attainment of marginal states in the material of structural components are formulated on the basis of analysis of force and deformation criteria of formation and development of destruction. The parameters of these criteria are data on types of structural materials, standard and special characteristics of their mechanical properties, structural forms of considered elements of the equipment, and their operating stress loading. In this case, the construction of a system of state equations for describing interrelation of current damage, external actions, and responses to them is based on the concept of calculating variations in properties of materials at all stages of the design life cycle.