共查询到20条相似文献,搜索用时 921 毫秒
1.
2.
3.
提出了一种基于活塞式体积管的新型热量表动态检定技术.阐述了热量表检定装置的工作原理,设计了一种以工控机为控制核心,在VC++环境下进行数据自动采集及过程控制,实现检定参数实时准确测试的高精度热量表检定系统,从理论上分析了影响热量表热水流量检测系统的不确定度因素.研究表明,相对于现有的以质量法结合标准表法的热量表检定方法,本方案能有效提高热量表检定效率和精度. 相似文献
4.
本刊讯目前 ,国家质量监督检验检疫总局在天津市召开了热量表检定装置科研成果鉴定会。来自我国“三北地区”的热计量领域的与会专家对天津市赛恩电子公司研制的热量表整体检定装置的新技术成果予以了充分的肯定。该产品通过科研成果鉴定也填补了我国在热量表检定设备领域的空白。该热量表整体检定装置在技术上充分吸纳了我国热量表 ,热流体流量标准装置等十几种技术标准 ,检定规程及技术文献的内容 ,同时 ,借鉴了国外同类产品的特点 ,因而具有较强的实用性。该检定装置可对生产中和实际使用中的3级精度的热量表直接进行检定 ,实现了热量表… 相似文献
5.
6.
7.
文章通过对热量表热量计算的分析以及热量表检定装置温差测量结果的不确定度评定,提出适宜我国热量表检定装置温差测量标准器的使用方案。 相似文献
8.
9.
10.
11.
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. 相似文献
12.
Liebert A Wabnitz H Grosenick D Möller M Macdonald R Rinneberg H 《Applied optics》2003,42(28):5785-5792
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. 相似文献
13.
14.
15.
本文根据多年的实践检定经验 ,参照JJF1 0 59- 1 999《测量不确定度评定与表示》以及《测量不确定度表达 1 0讲》 ,对卧式金属罐容量的测量结果不确定度进行了评定。 相似文献
16.
17.
18.
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. 相似文献
19.
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. 相似文献
20.
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。 相似文献