0.1～0.2级携带式直流双臂电桥示值误差的测量不确定度评定

依据ＪＪＧ１２－８６《直流电桥检定规程》,采用整体检定法,按ＪＪＧ１０５９－１９９９《测量不确定度评定与表示》对０．１～０．２级携带式直流双臂电桥示值误差的测量不确定度进行分析计算。     

0.01级高电势直流电位差计示值误差的测量不确定度

依据ＪＪＧ１２３－８８《直流电位差计检定规程》,采用补偿测量法,按ＪＪＧ１０５９－１９９９《测量不确定度评定与表示》对０．０１级直流电位差计电动势值的测量不确定度进行分析计算。     

二等标准热电偶在419.527℃～1084.62℃范围内的不确定度评定

在ＩＴＳ－９０之后，按照ＪＩＦ１０５９《测量不确定度评定与表示》，对二等标准铂锗１０－铂热电偶在三个检定点（铜固定点，铝固定点，锌固定点）上的不确定度进行评定，并介绍其在４１９．５２７℃￣１０８４．６２℃温区范围内的整百度点不确定度分析，给出了温度－不确定度曲线。     

用锌凝固点和水沸点检定二等标准铂电阻温度计的扩展不确定度评定

按时规范,ＪＪＦ１０５９－１９９９,对二等标准铂电阻温度计在锌凝固点及水沸点检定的不确定度进行了评定,通过建立测量数学模型确定各标准各不确定度分量,并按不确定度传播公式给出固定点间各温度点的扩展不确定度及包含因子。     

合成标准不确定度评定中的负相关一例

自从ＪＪＦ１０５９—１９９９《测量不确定度评定与表示》宣贯实施以来 ,各领域测量结果的不确定度评定就有了统一的、并与国际通行做法接轨的技术规范。随着ＪＪＦ１０６９—２０００《法定计量检定机构考核规范》和ＪＪＦ１０３３—２００１《计量标准考核规范》的批准和实施 ,无论计量机构的考核还是计量标准的考核 ,都对测量不确定度评定提出了相应要求 ,因此 ,正确理解和掌握不确定度的评定成为计量工作者必备的知识。在不确定度评定过程中 ,合成不确定度计算的关键问题是求出灵敏系数和确定输入量估计值是否相关 ,而对于较复杂的函数…     

0℃～961.78℃范围温度基准的不确定度评定

本文根据《测量不确定度表示指南》的统一准则,重新评定了０℃￣９６１．７８℃范围温度基准的不确定度,以基准银凝固点为例介绍了不确定度的评定方法,并给出温度基准各定义固定点的扩展不确定度及包含因子。     

收敛计技术性能的检定与不确定度评定

本文介绍收敛计的工作特性、仪器常数、检定基线场、收敛计的静动态测试其不确定度评定,并给出ＳＷＪ－Ⅳ新型隧道收敛计不确定度的证实实例。     

GKJ-1.8m激光自动线位移刻检系统检测长光栅传感器误差分析及评定

对"ＧＫＪ－１．８ｍ激光自动线位移刻检系统"进行了较系统的误差分析,用仪器的系统误差和随机误差合成的方法,评定本仪器测试长光栅传感器光栅位置误差的不确定度．     

对测量不确定度评定的探讨

本文是对业已颁布实施的国家计量技术规范ＪＪＦ１０５９－１９９９《测量不确定度评定与表示》（以下简称《规范》）中尚未明确的部分进行探讨。     

测量不确定度表述讲座 第六讲 标准测量不确定度的B类评定

６ １什么叫不确定度的Ｂ类评定？测量不确定度的评定方法主要分成两大类。一类是用统计方法进行评定 ,称之为Ａ类评定（参阅１ ２）,而其他的非统计方法 ,统称之为Ｂ类评定 ,又称之为非统计方法的评定 ,由此评定出来的不确定度一般称为Ｂ类不确定度或称为Ｂ类标准不确定度。要注意的是ＩＮＣ—１（１９８０）（参阅１ ２）中以及《ＪＪＦ１０２７》中都曾规定Ａ类不确定度分量用符号ｓｉ,而Ｂ类不确定度分量用符号ｕｊ 表示 ,这一方式在《导则》以及《ＪＪＦ１０５９》中已作了更改 ,ｓ只是实验标准偏差的符号 ,当它作为不确定度时 ,则不论…     

K荧光X射线光子注量测量方法研究

K荧光因为拥有良好的单能性而被用于刻度校准仪器仪表.K荧光产额与单能性直接关系着刻度的准确性.利用RC6M电离室,测量锆(Zr)、硫酸铯(Cs2SO4)、钨(W)3种材料分别作为辐射体时的电离电流,计算得出其空气比释动能,进而求出K荧光辐射场在60cm处的光子注量.结果显示,计算得出的光子注量率在107～109m-2·s-1的量级.分析了K荧光X射线光子注量的不确定度的来源,最终计算得出当用Zr作为辐射体时,光子注量的相对扩展不确定度为5.78％,当用Cs2S04作为辐射体材料时,光子注量的相对扩展不确定度为1.08％,当用W作为辐射体材料时,光子注量的相对扩展不确定度为1.34％.     

100～400K真空红外亮温标准黑体辐射源研制

介绍了中国计量科学研究院研制的100~400K真空红外亮温标准黑体辐射源的工作原理、结构、性能测试方法及测试结果。黑体辐射源通过液氮制冷与3温区控制实现了100~400K范围内的温度控制。在真空环境下,测试了其在温度范围100~400K轴向温度均匀性、底部温度稳定性等技术指标,结果表明均匀性优于0.120K,控温稳定性优于0.020K/20min;在室温大气环境下,利用基于控制环境辐射的发射率测量方法测量了黑体空腔发射率,空腔法向发射率为0.9998。采用基于蒙特卡罗黑体发射率仿真计算方法分析轴向温度均匀性对空腔发射率的影响,分析了标准黑体辐射源的不确定度来源,在8~16 μm波长亮度温度的合成标准不确定度优于0.030K。     

U.K. National Radiological Protection Board Radon Calibration Procedures

A procedure for the calibration of instruments for the detection of ²²²Rn in air is described. The method is based on the alpha-spectrometric determination of the concentration in air of ²¹⁸Po in the calibration chamber. The calibration chamber is described, together with the method of maintaining a high aerosol concentration. The ²¹⁸Po concentration at steady state in the chamber is found to be 98% of the ²²²Rn concentration typically. An assessment of the sources of uncertainty in the method presented indicate that the ²²²Rn concentration in the chamber can be determined with an overall uncertainty of about 7% at the 95% confidence level.     

Challenge problems: uncertainty in system response given uncertain parameters

The risk assessment community has begun to make a clear distinction between aleatory and epistemic uncertainty in theory and in practice. Aleatory uncertainty is also referred to in the literature as variability, irreducible uncertainty, inherent uncertainty, and stochastic uncertainty. Epistemic uncertainty is also termed reducible uncertainty, subjective uncertainty, and state-of-knowledge uncertainty. Methods to efficiently represent, aggregate, and propagate different types of uncertainty through computational models are clearly of vital importance. The most widely known and developed methods are available within the mathematics of probability theory, whether frequentist or subjectivist. Newer mathematical approaches, which extend or otherwise depart from probability theory, are also available, and are sometimes referred to as generalized information theory (GIT). For example, possibility theory, fuzzy set theory, and evidence theory are three components of GIT. To try to develop a better understanding of the relative advantages and disadvantages of traditional and newer methods and encourage a dialog between the risk assessment, reliability engineering, and GIT communities, a workshop was held. To focus discussion and debate at the workshop, a set of prototype problems, generally referred to as challenge problems, was constructed. The challenge problems concentrate on the representation, aggregation, and propagation of epistemic uncertainty and mixtures of epistemic and aleatory uncertainty through two simple model systems. This paper describes the challenge problems and gives numerical values for the different input parameters so that results from different investigators can be directly compared.     

100ml容量瓶容量测量结果的不确定度评定

主要叙述了在100ml容量瓶的检定过程中,对其容量测量结果的不确定度的评定     

广义不确定性系统理论的外延综论

在概述广义不确定性系统内涵基础上，讨论了广义不确定性系统的外延类别及其相关理论的基本研究框架和基本原理，为深入研究广义不确定性系统理论奠定了基础。     

考虑不确定性的多学科设计优化方法研究综述

目的研究多学科不确定性设计优化中多学科设计优化方法、不确定性建模与传递、不确定性设计优化的相关理论。方法通过研究并分析国内外相关文献,总结归纳考虑不确定性的多学科设计优化中的耦合系统解耦方法、参数和代理模型不确定性的建模方法,以及高效的不确定性传递和设计优化方法。结论系统探讨了在面对复杂多变的外界环境时,多学科设计优化对不确定性量化与传递的需求,提出多学科设计优化不仅要考虑确定性的系统,而且需要考虑由于外界环境变化导致的系统响应的不确定性。针对现有的多学科不确定性设计优化方法的理论研究,提出提高计算效率的关键在于将传统的三层嵌套循环计算框架解耦成单层循环。研究结果表明,考虑不确定性的多学科设计优化将成为复杂多学科系统设计的有力支撑,能显著提高系统的可靠性和稳健性,提高使用寿命,同时能够加快产品的更新换代设计。     

A probabilistic approach for representation of interval uncertainty

In this paper, we propose a probabilistic approach to represent interval data for input variables in reliability and uncertainty analysis problems, using flexible families of continuous Johnson distributions. Such a probabilistic representation of interval data facilitates a unified framework for handling aleatory and epistemic uncertainty. For fitting probability distributions, methods such as moment matching are commonly used in the literature. However, unlike point data where single estimates for the moments of data can be calculated, moments of interval data can only be computed in terms of upper and lower bounds. Finding bounds on the moments of interval data has been generally considered an NP-hard problem because it includes a search among the combinations of multiple values of the variables, including interval endpoints. In this paper, we present efficient algorithms based on continuous optimization to find the bounds on second and higher moments of interval data. With numerical examples, we show that the proposed bounding algorithms are scalable in polynomial time with respect to increasing number of intervals. Using the bounds on moments computed using the proposed approach, we fit a family of Johnson distributions to interval data. Furthermore, using an optimization approach based on percentiles, we find the bounding envelopes of the family of distributions, termed as a Johnson p-box. The idea of bounding envelopes for the family of Johnson distributions is analogous to the notion of empirical p-box in the literature. Several sets of interval data with different numbers of intervals and type of overlap are presented to demonstrate the proposed methods. As against the computationally expensive nested analysis that is typically required in the presence of interval variables, the proposed probabilistic representation enables inexpensive optimization-based strategies to estimate bounds on an output quantity of interest.     

检定立式金属罐容量测量不确定度的研究

本文结合立式金属罐的容量测量实例，详述了标准不确定度的计算及扩展不确定度的获得过程。     

测量不确定度评定方法在电学计量中的应用研究

介绍了测量不确定度评定理论,论述了在对电学仪器进行计量校正所采用的理论,并分析了各种不确定度的特点和适用性,为电学仪器的计量提供参考并指出发展方向.