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测量不确定度的评定和表述适用于计量检定、计量校准,它和误差是计量学中研究的基本命题,是计量测试技术人员经常运用的重要概念之一,它直接关系着测量结果的可靠程度和量值传递的准确一致。鉴于测量不确定度在检测,校准和合格评定中的重要性和影响,现就有关测量不确定度概念、测量不确定度的评定和表示方法作一介绍。 相似文献
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随着<检测和校准实验室能力的通用要求>与<法定计量检定机构考核规范>的实施,对榆测或校准结果提出了更高的要求,不但要提供检测或校准结果的数据,还应提供检测或校准结果的测量不确定度. 相似文献
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不确定度是一个不常用的计量术语,ISO9001标准及ISO10012-1标准要求测量设备的不确定度要已知,同时技术监督部门要求企业计量检测、检定(校准)作业中要给出不确定度。我们在贯彻ISO10012-1标准完善企业计量检测体系活动中,虽贯彻了这些要求,并按辽宁省技术监督局编写的培训资料《误差理论与测量不确定度表达》一书中的方法进行计算后出具在检定(校准)记录及证书上。由于不确定度在企业中应用尚在起步阶段,目前仍有相当数量检定(校准)人员对不确定度的作用还不大清楚,也就是仅看到增加了繁琐计算未看到应用价值,以至影响… 相似文献
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两种统计方法用于不确定度A类评定的分析与比较 总被引:1,自引:0,他引:1
正在计量校准领域中,测量得到的结果必须有相应的测量不确定度描述才是完整的。给定了测量结果及对应的测量不确定度,便能确定被测量的真值以一定的概率(比如95%)处于一个确定的区间。测量不确定度是描述测量结果分散性的指标,如何评价这一指标所依据的主要文件是ISO联合7个国际组织发布的测量不确定度评估指南GUM及补充文件S1、S2等。各个国家计量机构和校准实验室均按照该标准文件体系对测量结果进行评估,这样能确保不同实验室校准得 相似文献
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Kamlesh Goel 《Scientometrics》2002,55(2):243-258
An analysis of gender differences in psychology in India provides quantitative and qualitative assessment of R&D output contributed by psychologists with the indication of the trend of growth, skewness, relatedness, co-authorship pattern of productivity. 相似文献
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The system for Metrology in Chemistry in Germany is described. At the national standards level, a network of high-level chemistry
institutes coordinated by the national metrology institute, PTB, provides the primary references for chemical measurements.
A dissemination mechanism employs chemical calibration laboratories accredited within the framework of the German Calibration
Service (DKD). They act as “multipliers” between the national standards level and the user level by providing the user with
calibration means which are traceable to the SI via national standards. Traceability structures in clinical chemistry, electrochemistry,
elemental analysis and gas analysis are described 相似文献
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Radiation Protection Dosimetry 相似文献
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Natural radioactivity in drinking water was determined in population-based random study of 472 private wells. The mean concentrations of (222)Rn, (226)Ra, (234)U, (238)U, (210)Pb and (210)Po in drilled wells were 460, 0.05, 0.35, 0.26, 0.04 and 0.05 Bq l(-1), and in wells dug in the soil were 50, 0.016, 0.02, 0.015, 0.013 and 0.007 Bq l(-1), respectively. Approximately 10% of the drilled wells exceeded a radon concentration of 1000 Bq l(-1) and 18% a uranium concentration of 15 microg l(-1). The mean annual effective dose from natural radionuclides for a drilled well user was 0.4 mSv and 0.05 mSv for a user of a well dug in the soil. The effective dose arising from (222)Rn was 75% of the total of all natural radionuclides for drilled well users. As regards long-lived radionuclides, (210)Po and (210)Pb caused the largest portion of the effective dose. The dose arising from (238)U, (234)U and (226)Ra was only 8% of the total of all natural radionuclides. 相似文献
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Ward Vanlaar Robyn Robertson Kyla Marcoux Daniel Mayhew Steve Brown Paul Boase 《Accident; analysis and prevention》2012
While a general decreasing trend in the number of persons killed in a traffic crash involving a drinking driver has occurred in Canada since the 1980s, it is evident that much of this decrease occurred in the 1990s. Since 2002, less progress has been made as the number of persons killed in crashes involving drinking drivers remains high. To better understand the current situation, this paper describes trends in drinking and driving in Canada from 1998 to 2011 using multiple indicators based on data collected for the Traffic Injury Research Foundation's (TIRF) Road Safety Monitor (RSM), the National Opinion Poll on Drinking and Driving, and trends in alcohol-related crashes based on data collected for TIRF's national Fatality Database in Canada. There has been a continued and consistent decrease in the number of fatalities involving a drinking driver in Canada. This remains true when looking at the number of fatalities involving a drinking driver per 100,000 population and per 100,000 licensed drivers. This decreasing trend is also still apparent when considering the percentage of persons killed in a traffic crash in Canada involving a drinking driver although less pronounced. Data from the RSM further show that the percentage of those who reported driving after they thought they were over the legal limit has also declined. However, regardless of the apparent decreasing trend in drinking driving fatalities and behaviour, reductions have been relatively modest, and fatalities in crashes involving drivers who have consumed alcohol remain high at unacceptable levels. 相似文献
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Ali KK 《Radiation protection dosimetry》2012,148(3):372-379
Activity concentrations of (226)Ra, (232)Th and (40)K in 45 samples of different building materials used in Iraq were measured using gamma-spectroscopy system based on high-purity germanium detector with an efficiency of 40 %. Radium equivalent activity, air-absorbed dose rate, annual effective dose, external and internal hazard indices and alpha index due to radon inhalation originating from building materials were measured to assess the potential radiological hazard associated with these building materials. The activity concentrations of the natural radionuclides (226)Ra, (232)Th and 40K were found to range from below detection limit (BDL) to 223.7 ± 9, BDL to 93.0 ± 3 and BDL to 343.1 ± 12, respectively. Values of average radium equivalent activity, air-absorbed dose rate, indoor and outdoor annual effective doses, external and internal hazard indices and alpha index ranged from 6.5 to 124.9, 16.2 to 89.5 (nGy h(-1)), 0.08 to 0.44 mSv, 0.02-0.11 mSv, 0.09 to 0.53, 0.13 to 0.69 and 0.03 to 0.62, respectively. These values indicate a low dose. Therefore, the building materials used in the current study are quite safe to be used as building materials. 相似文献
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