一种动态计重收费系统(轴重仪)校准方法

本文提出了一种动态轴重仪的校准方法．并通过对各种路面情况的分析,得出了各种路面对测量数据的影响．定性的分析了各种路面对动态测量的影响．论证了这种方法具有一定的科学合理性、简单实用性。     

便携式制动性能测试仪校准时应引起注意的问题

根据所做减速度仪校准情况的汇总,其静态校准基本能满足JJF 1168—2007《便携式制动性能测试仪校准规范》(以下简称《规范》)规定的技术要求。而其动态校准基本上都是不能满足《规范》规定的技术要求的。文章将减速度仪校准中所存在的问题提出来,以供同行参考、共同探讨。     

微波消解仪温场校准及结果分析

通过对微波消解仪的工作原理及微波特性分析,结合目前微波消解仪温场校准现状,探讨了一种微波消解仪温场动态校准方法,校准参数包含温度示值误差,温度均匀度,温度波动度,校准结果真实地反映了微波消解仪实际工作中的动态温场状态。     

轴重仪的正确使用与配套汽车衡的选用

我单位是建筑安装施工企业 ,主要从事大型的工业与民用建筑及安装。在计量器具的合理配置及校准间隔的确定方面 ,我们进行了一些尝试 ,取得了效益。在个别项目部我们安装了轴重仪 ,汽车一过直接读取数值打印单据。据收料部门统计 ,一年光砂石料一项就少支付二十几万元。但在使用中我们发现 ,轴重仪是对汽车每一轮轴通过台面时份量相加得出整车物资总量 ,每个轴重均会产生不同误差。下面几个因素都会影响轴重仪的准确度 :（１）汽车过轴重仪时的速度、方向 ;（２）轴重仪前后备用跑道要与台面水平 ,并且足够长 ;（３）汽车过轴重仪台面时不能…     

EL红外缺陷测试仪关键参量校准方法研究

基于空间频率响应测试方法,搭建了EL红外缺陷测试仪关键参量的校准装置。分析了对焦以及位置摆放对分辨率校准结果的影响;给出了便携式和固定式EL红外缺陷测试仪相应的测试方法及操作流程。提出了一种针对便携式的测试方法,可以实现无参考背景情况下的校准工作。基于该校准装置可对各类EL测试仪的分辨率参数进行校准,测量结果重复性较好。     

动态轴重仪在不同路面情况时的受力分析

本文对动态轴重仪在各种路面情况时的受力作了分析，得出了不同路面情况对动态轴重仪测量数据的影响。     

基于固定优先级算法的便携式检定仪自动校准

针对研发的军用便携式检定仪计量校准的需求,设计了校准量值的传递与保证方案,提出一种基于固定优先级的自动校准算法.该算法中,占用相同校准资源的校准任务按优先级执行,占用不同校准资源的校准任务则并行执行,充分利用了校准资源.通过以太网接口进行数据通讯,设计了自动校准程序,实现了便携式检定仪自动化校准.     

便携式制动性能测试仪校准过程

论述了便携式制动性能测试仪的校准概况、静态和动态校准过程及其注意事项,并以实例阐述了在期间核查等情况下标准器校准结果的验证方法,最后对文章进行总结,指出目前便携式制动性能测试仪校准过程存在的问题并说明校准的必要性。     

基于速度三角波的激光跟踪仪动态定位误差校准技术的研究北大核心CSCD

激光跟踪仪作为大尺寸精密坐标测量仪器,其动态定位误差精度备受关注。而其校准技术还停留在静态校准和动态跟踪性能校准的状态下。在少有对激光跟踪仪动态定位误差校准的前提下,通过对激光跟踪仪的误差分析,提出了基于速度三角波的激光跟踪仪动态定位误差校准方法,并对校准模型中运动目标的规律和运动轨迹进行了分析,设计了激光跟踪仪校准实验。实验结果论证了校准方案的可行性和必要性,对最大测量速度赋予了更为详细的定义。     

基于虚拟仪器的机动车制动台及轴重仪检测

汽车制动性能的检测中,除了设置制动试验台外,还必须配备轴重计或轮重仪。现场的力值测量往往对测量仪器使用的环境条件有一定要求。因此,我们采用虚拟仪器技术设计开发了USB-9237便携式应力测量仪(以下简称"测量仪")。它是特为现场应力测量而设计、开发的一种便携式应力测量仪器。它具有四通道同步测量能力,并且可以进行动态应变测量。     

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.     

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.     

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。     

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.     

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.     

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.     

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)。