共查询到20条相似文献,搜索用时 796 毫秒
1.
测量不确定度是完整测量结果的一部分.由于测试方法的特性,部分电器安全检测项目很难从计量学和统计学的角度进行有效的、严格的测量不确定度计算,因此,有关电器安全检测结果的不确定度评估还处于尝试阶段.本文根据标准规定的方法,建立相应的数学模型,对电器产品泄漏电流测量结果的不确定度来源进行分析,并给出各不确定度分量以及合成不确定度的计算方法,以及结果的报告. 相似文献
2.
3.
4.
本文采用原子荧光法测定鱼粉中硒的含量,结合特定测量方法和不确定度评定规范,分析影响测定结果质量的不确定度,并对不确定度进行评估,最终给出扩展不确定度,真实反映测量的置信度和准确度。 相似文献
5.
为保证测量结果的准确性,对商品试剂盒微生物法测定鸡枞菌中叶酸含量不确定度进行分析。依据CNASCL01-G003-2019要求,并按照JJF 1059.1-2012和GB/Z 22553-2010对实验结果有影响的各个分量进行评估,即对样品测定重复性、样品称量、样品检测过程三个方面引入的不确定度进行分析,并确定了各不确定度分量,得出扩展不确定度。各分量不确定度从大到小分别为样品测定重复性0.0272、移液枪自身容差0.0226、标准品纯度0.002887、温度变化0.0006、容量瓶定容0.0006、样品称量0.00001633;相对合成标准不确定度为0.0356,扩展不确定度为7.7857,测量结果为(109.35±7.7857)μg/100 g。影响微生物法测定鸡枞菌中叶酸含量的最主要不确定度分量为样品测定重复性、移液枪自身容差、标准品纯度引入的不确定度。 相似文献
6.
7.
8.
《粮食流通技术》2018,(24)
对高效液相色谱-质谱/质谱联用法检测鸡蛋中氯霉素残留的测量不确定度进行评定。参照GB/T 22338-2008中的液相色谱-质谱/质谱法检测鸡蛋样品,依据测量不确定度评定的相关指导文件建立了不确定度数据模型,分析了检测过程中可能引入的不确定度来源,并算出测量结果的合成标准不确定度和扩展不确定度。当鸡蛋样品中残留量为0.493μg·kg~(-1)时,其扩展不确定度为U=0.020 3×2=0.040 6μg·kg~(-1),氯霉素残留量为(0.493±0.0406)μg·kg~(-1)(k=_2)。实验过程中引入的不确定度对检测结果影响较大的主要有标准物质配制、样品重复测定、标准曲线拟合以及仪器定量校准;而标准物质称量、样品称重质量、最终定容体积以及样品回收率等引入的不确定度分量对检测结果影响相对较小。 相似文献
9.
"测量不确定度是表征合理赋予被测量之值的分散性,与测量结果相关系的参数,在测量结果的完整表述中,应包括测量不确定度".这是国家计量技术规范jjf1059-1999<测量不确定度评定与表示>中对测量不确定度的描述.任何测量都存在不确定度,因此,测量不确定度在实验室比对、测量结果临界值的判断、方法的确认以及检测工作国际化等方面都有重要的意义. 相似文献
10.
根据GB 5009.87-2016《食品安全国家标准食品中磷的测定》中的分光光度法测量试样。利用测量不确定度的评价方法和步骤建立数学模型,对食品中磷含量的分光光度法的不确定度进行评估。根据实验过程中的各个分量的不确定度来源进行分析,并对所有不确定度进行合成,得出分光光度法测定食品中磷含量不确定度评定结果。结果表明:当食品中的磷含量为12.87%时,其扩展不确定度为0.3%,k=2。 相似文献
11.
12.
13.
将通货膨胀因素引入到GARCH模型的方差方程中,以检验通货膨胀、通货膨胀变动以及通货膨胀不确定性对股市条件波动的影响。实证分析的结果表明,在统计意义上,通货膨胀及其变动对股市收益的条件波动几乎不会产生影响,而通货膨胀不确定性对股市波动的影响是显著的。这一结果意味着管理好通胀预期,降低通货膨胀不确定性,引导公众形成合理的通胀预期对促进股市平稳发展具有重要意义。 相似文献
14.
食品安全状态受诸多不确定性和动态可变性因素影响与控制,评价信息获取也存在局限性和不完整性,故其评价为复杂的系统不确定性问题。本文应用集对理论,探讨了基于联系隶属度的食品安全状态评价新模型,即应用集对联系隶属度刻画待评对象的实测指标值与评价标准间的同异反关系,进而结合权重综合评价食品安全状态。实例应用及与其他方法对比结果表明,该模型应用于食品安全评价是有效可行的,且具有评价结论客观与明确优点。 相似文献
15.
The lack of a vaccine for COVID-19 and the limited amount of reliable data on the cessation of the disease have made people feel more vulnerable to the disease. As a result, people in many countries have been found to engage in panic purchasing, which has adversely affected the supply system for the retail market. Applying behavioral inhibition system theory, reactance theory, and expectancy theory, this research examines how psychological factors such as uncertainty, perceptions of severity, perceptions of scarcity, and anxiety affected the panic purchasing behavior of consumers. This study was conducted in Malaysia in light of the 2020 outbreak of the COVID-19 pandemic. The results from structural equation modeling indicate that uncertainty, and perceptions of scarcity are positively associated with anxiety but not with the panic purchasing behavior of consumers. In addition, anxiety fully mediates the relationship among these variables and the panic purchasing behavior of consumers. Taken together, these findings provide support for doing more empirical research in order to develop a more resilient retail strategy and to improve consumer service. 相似文献
16.
Forecasting is a daunting challenge for business economists and policymakers, often made more difficult by pervasive uncertainty. One such uncertainty is the reaction of policymakers to major shifts in the economy. We explore the process by which the Federal Reserve Open Market Committee (FOMC) came to recognize and react to the productivity acceleration of the 1990s. Initial impressions were formed importantly by anecdotal evidence. Then, FOMC members—and chiefly Federal Reserve Board Chairman Alan Greenspan—came to mistrust the data and the forecasts. Eventually, revisions to published data confirmed initial impressions. Our main conclusion is that the productivity-driven positive supply side shocks of the 1990s were initially viewed favorably. However, over time they came to be viewed as posing a threat to the economy, chiefly through unsustainable increases in aggregate demand growth that threatened to increase inflation pressures. Perhaps nothing so complicates business planning and forecasting as policymakers who initially embrace an unanticipated shift and later come to abhor the same shift. 相似文献
17.
综合运用预算估计行为实验,以浙江省250家企业为样本进行实证研究,研究文化和不确定性如何影响个体预算行为,进而影响企业层面的预算管理,最终造成预算偏见。研究发现个体预算行为在不确定性估计、个人风格差异下存在偏差;企业文化和感知的环境不确定程度对预算参与程度和预算监控程度有显著的影响;感知环境的不确定性会降低预算超支,也会降低预算松弛;在文化和环境背景下预算行为会出现很强的交互作用,只有一定的组合才是最有效的。 相似文献
18.
Valentin Zahrnt 《International Trade Journal》2013,27(4):361-398
The observation has frequently been made that uncertainty about the legal meaning and the economic and political effects of WTO agreements exert a discouraging effect on the progress of multilateral trade negotiations. This article identifies the determinants of uncertainty and risk in the WTO. It also examines changes in these determinants over time, pointing to increasing levels of uncertainty and risk. The argument is based on a series of interviews conducted with members of national delegations to the WTO and with WTO employees. 相似文献
19.
传统的经济学理论虽然给人类经济发展作出过重大贡献,但随着社会经济的发展日显其局限}生。本文通过对经济学发展吏的回顾,总结了传统西方经济学理论假设的荒谬性和经济学基本理论的局限性;分析了由于具有主动性的人参与到经济系统中而产生的个体的主动性、相互作用的非线性、整体发展的不确定性、信息和信息系统的重要作用等复杂性特.最;介绍了复杂系统科学的发展,分析了复杂系统科学的马克思主义哲学原理;最后探讨了现代经济学理论的发展方向。 相似文献