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Statistical Diagnosis and Gross Error Test for Semiparametric Linear Model 被引量:1
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作者 DING Shijun ZHANG Songlin JIANG Weiping WANG Shouchun 《Geo-Spatial Information Science》 2009年第4期296-302,共7页
This paper systematically studies the statistical diagnosis and hypothesis testing for the semiparametric linear regression model according to the theories and methods of the statistical diagnosis and hypothesis testi... This paper systematically studies the statistical diagnosis and hypothesis testing for the semiparametric linear regression model according to the theories and methods of the statistical diagnosis and hypothesis testing for parametric regression model.Several diagnostic measures and the methods for gross error testing are derived.Especially,the global and local influence analysis of the gross error on the parameter X and the nonparameter s are discussed in detail;at the same time,the paper proves that the data point deletion model is equivalent to the mean shift model for the semiparametric regression model.Finally,with one simulative computing example,some helpful conclusions are drawn. 展开更多
关键词 parametric regression semiparametric linear model influencing analysis statistical diagnosis gross error testing
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A flexible and robust soft-error testing system for microelectronic devices and integrated circuits
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作者 王晓辉 童腾 +7 位作者 苏弘 刘杰 张战刚 古松 刘天奇 孔洁 赵兴文 杨振雷 《Nuclear Science and Techniques》 SCIE CAS CSCD 2015年第3期64-70,共7页
Single event effects(SEEs) induced by radiations become a significant challenge to the reliability for modern electronic systems. To evaluate SEEs susceptibility for microelectronic devices and integrated circuits(ICs... Single event effects(SEEs) induced by radiations become a significant challenge to the reliability for modern electronic systems. To evaluate SEEs susceptibility for microelectronic devices and integrated circuits(ICs), an SEE testing system with flexibility and robustness was developed at Heavy Ion Research Facility in Lanzhou(HIRFL). The system is compatible with various types of microelectronic devices and ICs, and supports plenty of complex and high-speed test schemes and plans for the irradiated devices under test(DUTs). Thanks to the combination of meticulous circuit design and the hardened logic design, the system has additional performances to avoid an overheated situation and irradiations by stray radiations. The system has been tested and verified by experiments for irradiating devices at HIRFL. 展开更多
关键词 微电子器件 测试系统 集成电路 软误差 重离子研究装置 HIRFL 现代电子系统 辐照装置
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Comparison of Type I Error Rates of Siegel-Tukey and Savage Tests among Non-Parametric Tests
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作者 Sahib Ramazanov Hakan Çora 《Open Journal of Applied Sciences》 2024年第9期2393-2410,共18页
This study aimed to examine the performance of the Siegel-Tukey and Savage tests on data sets with heterogeneous variances. The analysis, considering Normal, Platykurtic, and Skewed distributions and a standard deviat... This study aimed to examine the performance of the Siegel-Tukey and Savage tests on data sets with heterogeneous variances. The analysis, considering Normal, Platykurtic, and Skewed distributions and a standard deviation ratio of 1, was conducted for both small and large sample sizes. For small sample sizes, two main categories were established: equal and different sample sizes. Analyses were performed using Monte Carlo simulations with 20,000 repetitions for each scenario, and the simulations were evaluated using SAS software. For small sample sizes, the I. type error rate of the Siegel-Tukey test generally ranged from 0.045 to 0.055, while the I. type error rate of the Savage test was observed to range from 0.016 to 0.041. Similar trends were observed for Platykurtic and Skewed distributions. In scenarios with different sample sizes, the Savage test generally exhibited lower I. type error rates. For large sample sizes, two main categories were established: equal and different sample sizes. For large sample sizes, the I. type error rate of the Siegel-Tukey test ranged from 0.047 to 0.052, while the I. type error rate of the Savage test ranged from 0.043 to 0.051. In cases of equal sample sizes, both tests generally had lower error rates, with the Savage test providing more consistent results for large sample sizes. In conclusion, it was determined that the Savage test provides lower I. type error rates for small sample sizes and that both tests have similar error rates for large sample sizes. These findings suggest that the Savage test could be a more reliable option when analyzing variance differences. 展开更多
关键词 Non-Parametric test Siegel-Tukey test Savage test Monte Carlo Simulation Type I error
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Identification of Kinematic Errors of Five-axis Machine Tool Trunnion Axis from Finished Test Piece 被引量:3
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作者 ZHANG Ya FU Jianzhong CHEN Zichen 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2014年第5期999-1007,共9页
Compared with the traditional non-cutting measurement,machining tests can more accurately reflect the kinematic errors of five-axis machine tools in the actual machining process for the users.However,measurement and c... Compared with the traditional non-cutting measurement,machining tests can more accurately reflect the kinematic errors of five-axis machine tools in the actual machining process for the users.However,measurement and calculation of the machining tests in the literature are quite difficult and time-consuming.A new method of the machining tests for the trunnion axis of five-axis machine tool is proposed.Firstly,a simple mathematical model of the cradle-type five-axis machine tool was established by optimizing the coordinate system settings based on robot kinematics.Then,the machining tests based on error-sensitive directions were proposed to identify the kinematic errors of the trunnion axis of cradle-type five-axis machine tool.By adopting the error-sensitive vectors in the matrix calculation,the functional relationship equations between the machining errors of the test piece in the error-sensitive directions and the kinematic errors of C-axis and A-axis of five-axis machine tool rotary table was established based on the model of the kinematic errors.According to our previous work,the kinematic errors of C-axis can be treated as the known quantities,and the kinematic errors of A-axis can be obtained from the equations.This method was tested in Mikron UCP600 vertical machining center.The machining errors in the error-sensitive directions can be obtained by CMM inspection from the finished test piece to identify the kinematic errors of five-axis machine tool trunnion axis.Experimental results demonstrated that the proposed method can reduce the complexity,cost,and the time consumed substantially,and has a wider applicability.This paper proposes a new method of the machining tests for the trunnion axis of five-axis machine tool. 展开更多
关键词 five-axis machine tool kinematic errors trunnion axis test piece error-sensitive directions
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Dynamics and Attitude Error Analysis for Dock Test System of Small Satellite
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作者 张元 孙丽丽 +1 位作者 赖一楠 戴野 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2015年第4期372-379,共8页
To analyze the attitude errors of vertical docking test system of small satellite,the static error and kinematic error of test system are considered.The working principle of test system and coordinate of actuator are ... To analyze the attitude errors of vertical docking test system of small satellite,the static error and kinematic error of test system are considered.The working principle of test system and coordinate of actuator are introduced.The model of friction torque on the joints and torque on docking mechanism are built.Dynamics equation of actuator is built by the Lagrange equation and the Nielsen equation.Under the condition of 24 different angle groups,the calculation of dynamics equation is built by using MATLAB/SIMULINK platform and the kinematic errors of actuator are obtained.The attitude error models of docking mechanism are built.Results shows that the main angle error sources of yaw,row,pitch are not identical.The attitude error of yaw angle can be decreased by compensating the angle error around xaxis.The attitude error of row angle mainly originates in the system error,and it can be eliminated by adjusting non-orthogonal degree. 展开更多
关键词 attitude error test system angle errors dynamics equation
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A Study on Measurement Error during Alternating Current Induced Voltage Tests on Large Transformers 被引量:1
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作者 WANG Xuan LI Yun-ge +1 位作者 CAO Xiao-long LIU Ying 《International Journal of Plant Engineering and Management》 2006年第1期17-24,共8页
The large transformer is pivotal equipment in an electric power supply system; Its partial discharge test and the induced voltage withstand test on large transformers are carried out at a frequency about twice the wor... The large transformer is pivotal equipment in an electric power supply system; Its partial discharge test and the induced voltage withstand test on large transformers are carried out at a frequency about twice the working frequency. If the magnetizing inductance cannot compensate for the stray capacitance, the test sample turns into a capacitive load and a capacitive rise exhibits in the testing circuit. For self-restoring insulation, a method has been recommended in IEC60-1 that an unapproved measuring system be calibrated by an approved system at a voltage not less than 50% of the rated testing voltage, and the result then be extrapolated linearly. It has been found that this method leads to great error due to the capacitive rise if it is not correctly used during a withstand voltage test under certain testing conditions, especiaUy for a test on high voltage transformers with large capacity. Since the withstand voltage test is the most important means to examine the operation reliability of a transformer, and it can be destructive to the insulation, a precise measurement must be guaranteed. In this paper a factor, named as the capacitive rise factor, is introduced to assess the rise. The voltage measurement error during the calibration is determined by the parameters of the test sample and the testing facilities, as well as the measuring point. Based on theoretical analysis in this paper, a novel method is suggested and demonstrated to estimate the error by using the capacitive rise factor and other known parame- ters of the testing circuit. 展开更多
关键词 TRANSFORMER test MEASUREMENT error
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On the Distribution of Type II Errors in Hypothesis Testing
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作者 Skip Thompson 《Applied Mathematics》 2011年第2期189-195,共7页
When a statistical test of hypothesis for a population mean is performed, we are faced with the possibility of committing a Type II error by not rejecting the null hypothesis when in fact the population mean has chang... When a statistical test of hypothesis for a population mean is performed, we are faced with the possibility of committing a Type II error by not rejecting the null hypothesis when in fact the population mean has changed. We consider this issue and quantify matters in a manner that differs a bit from what is commonly done. In particular, we define the probability distribution function for Type II errors. We then explore some interesting properties that we have not seen mentioned elsewhere for this probability distribution function. Finally, we discuss several Maple procedures that can be used to perform various calculations using the distribution. 展开更多
关键词 COMPLEMENTARY error Function HYPOTHESIS testing POWER CURVES POWER Surfaces Type II errorS
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TESTING OF CORRELATION AND HETEROSCEDASTICITY IN NONLINEAR REGRESSION MODELS WITH DBL(p,q,1) RANDOM ERRORS
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作者 刘应安 韦博成 《Acta Mathematica Scientia》 SCIE CSCD 2008年第3期613-632,共20页
Chaos theory has taught us that a system which has both nonlinearity and random input will most likely produce irregular data. If random errors are irregular data, then random error process will raise nonlinearity (K... Chaos theory has taught us that a system which has both nonlinearity and random input will most likely produce irregular data. If random errors are irregular data, then random error process will raise nonlinearity (Kantz and Schreiber (1997)). Tsai (1986) introduced a composite test for autocorrelation and heteroscedasticity in linear models with AR(1) errors. Liu (2003) introduced a composite test for correlation and heteroscedasticity in nonlinear models with DBL(p, 0, 1) errors. Therefore, the important problems in regression model axe detections of bilinearity, correlation and heteroscedasticity. In this article, the authors discuss more general case of nonlinear models with DBL(p, q, 1) random errors by score test. Several statistics for the test of bilinearity, correlation, and heteroscedasticity are obtained, and expressed in simple matrix formulas. The results of regression models with linear errors are extended to those with bilinear errors. The simulation study is carried out to investigate the powers of the test statistics. All results of this article extend and develop results of Tsai (1986), Wei, et al (1995), and Liu, et al (2003). 展开更多
关键词 DBL(p Q 1) random errors nonlinear regression models score test HETEROSCEDASTICITY CORRELATION
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Sensitivity and Specificity Analysis Relation to Statistical Hypothesis Testing and Its Errors: Application to Cryptosporidium Detection Techniques
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作者 Emmanuel de-Graft Johnson Owusu-Ansah Angelina Sampson +1 位作者 Amponsah K. Samuel Abaidoo Robert 《Open Journal of Applied Sciences》 2016年第4期209-216,共8页
The use of Statistical Hypothesis Testing procedure to determine type I and type II errors was linked to the measurement of sensitivity and specificity in clinical trial test and experimental pathogen detection techni... The use of Statistical Hypothesis Testing procedure to determine type I and type II errors was linked to the measurement of sensitivity and specificity in clinical trial test and experimental pathogen detection techniques. A theoretical analysis of establishing these types of errors was made and compared to determination of False Positive, False Negative, True Positive and True Negative. Experimental laboratory detection methods used to detect Cryptosporidium spp. were used to highlight the relationship between hypothesis testing, sensitivity, specificity and predicted values. The study finds that, sensitivity and specificity for the two laboratory methods used for Cryptosporidium detection were low hence lowering the probability of detecting a “false null hypothesis” for the presence of cryptosporidium in the water samples using either Microscopic or PCR. Nevertheless, both procedures for cryptosporidium detection had higher “true negatives” increasing its probability of failing to reject a “true null hypothesis” with specificity of 1.00 for both Microscopic and PCR laboratory detection methods. 展开更多
关键词 Sensitivity SPECIFICITY Type I and II errors Detection Methods Hypothesis testing
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产前超声诊断胎儿尿道下裂:遗传学检测结果及误诊原因分析 被引量:1
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作者 李琳 辛丞 焦北鱼 《中国医学影像技术》 北大核心 2025年第4期627-631,共5页
目的 观察产前超声诊断尿道下裂胎儿确诊后遗传学检测结果及误诊原因。方法 回顾性分析206胎产前超声疑诊尿道下裂胎儿,记录其结局;对确诊病例评估产前超声是否显示其他异常,收集遗传学检测结果,分析孕妇年龄是否≥35岁及产前超声是否... 目的 观察产前超声诊断尿道下裂胎儿确诊后遗传学检测结果及误诊原因。方法 回顾性分析206胎产前超声疑诊尿道下裂胎儿,记录其结局;对确诊病例评估产前超声是否显示其他异常,收集遗传学检测结果,分析孕妇年龄是否≥35岁及产前超声是否显示合并其他异常与染色体或基因异常风险的相关性。结果 206胎中,生后确诊159例尿道下裂,产前超声阳性预测值为77.18%(159/206);其常见表现包括阴茎远端圆钝、阴茎短小、阴茎向腹侧弯曲及“郁金香征”,隐睾、室间隔缺损及胎儿生长受限等为常见合并异常。孕妇年龄≥35岁及产前超声合并其他异常均为尿道下裂胎儿存在染色体或基因异常的独立预测因素(P均<0.05)。单纯阴茎短小下弯、肾上腺皮质增生症及女性胎儿单纯小阴唇肥大等可致产前超声误诊。结论 超声产前诊断胎儿尿道下裂阳性预测值较高;孕妇年龄≥35岁及产前超声合并其他异常提示胎儿染色体或基因异常风险相对较高。 展开更多
关键词 尿道下裂 超声检查 产前 遗传学检测 误诊
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APPROXIMATE POWER OF HETEROSCEDASTICITY TEST IN NONLINEAR MODELS WITH ARIMA(0,1,0) ERRORS 被引量:1
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作者 Lin Jinguan Wei Bocheng Zhang Nansong 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2005年第4期423-430,共8页
This paper presents an approach for estimating power of the score test, based on an asymptotic approximation to the power of the score test under contiguous alternatives. The method is applied to the problem of power ... This paper presents an approach for estimating power of the score test, based on an asymptotic approximation to the power of the score test under contiguous alternatives. The method is applied to the problem of power calculations for the score test of heteroscedasticity in European rabbit data (Ratkowsky, 1983). Simulation studies are presented which indicate that the asymptotic approximation to the finite-sample situation is good over a wide range of parameter configurations. 展开更多
关键词 ARIMA (0 1 0) errors asymptotic approximation HETEROSCEDASTICITY local power nonlinear model score test.
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船模阻力试验不确定度分析与实践
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作者 宋磊 冯大奎 +1 位作者 刘曾 杨祥 《实验技术与管理》 北大核心 2025年第3期37-43,共7页
该文以某艇为研究对象,分析了其阻力试验过程中的误差源,结合二因次换算公式推导不确定度传递方程;按照线型加工缩比模型并在不同时间段开展重复试验,将测试结果换算至名义温度(15℃)状态下的总阻力系数和姿态数据;按照不确定度传递原... 该文以某艇为研究对象,分析了其阻力试验过程中的误差源,结合二因次换算公式推导不确定度传递方程;按照线型加工缩比模型并在不同时间段开展重复试验,将测试结果换算至名义温度(15℃)状态下的总阻力系数和姿态数据;按照不确定度传递原则分别分析模型精度、水物理特性、传感器精度和重复试验的不确定度,并完成合成不确定度计算。分析不确定度结果可得,为了试验测试精度,应在硬件条件允许的范围内尽量选择较小的缩尺比,针对较大模型和较大航速状态开展试验,同时对非排水型船,即使在阻力试验中也应保证重量分布与实船一致。 展开更多
关键词 阻力试验 不确定度 误差分析
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稀薄流区的摩阻测量技术及减阻试验
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作者 刘春风 何啸天 +2 位作者 苗文博 王雪枫 程晓丽 《航空学报》 北大核心 2025年第12期85-96,共12页
面向稀薄流区发展了基于摩阻天平的摩阻测量技术,并以提高表面光洁度实现减阻作为应用实例,在高超声速低密度风洞中设计了一种对比测量试验,包括带有光滑壁面和常规壁面的平板模型和摩阻天平,平板模型的光滑壁面和常规壁面对称布置,并... 面向稀薄流区发展了基于摩阻天平的摩阻测量技术,并以提高表面光洁度实现减阻作为应用实例,在高超声速低密度风洞中设计了一种对比测量试验,包括带有光滑壁面和常规壁面的平板模型和摩阻天平,平板模型的光滑壁面和常规壁面对称布置,并依次搭配感应面为光滑壁面和常规壁面的摩阻天平。天平结构体基于悬臂梁原理设计,考虑过载保护和热防护,并通过载荷渐进法实现与试验状态最为接近的微量摩阻载荷校准。通过风洞试验误差的定量评估和主动控制,感应面表面压力引入的误差可控制在1%以内,浮动头错位引入的误差可控制在2%以内。Ma=22的7次重复性风洞试验显示摩阻天平的测量标准偏差不超过2.9%,光滑壁面相比常规壁面可有效减阻,平均减阻率为25.1%。 展开更多
关键词 稀薄流 摩阻天平 光滑壁面 减阻 风洞试验 误差控制
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观测不确定性影响下黄河水源涵养区径流情势变化特征
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作者 张永勇 韩冰 +1 位作者 曹灿 翟晓燕 《地理学报》 北大核心 2025年第1期28-40,共13页
径流观测不确定性是水文学研究领域尚未解决的关键问题之一。当前研究多集中于观测不确定性的来源及其影响解析等,但关于观测不确定性对径流情势特征指标变化趋势的影响研究较少。本文利用1971—2020年黄河水源涵养区5个水文站(黄河源... 径流观测不确定性是水文学研究领域尚未解决的关键问题之一。当前研究多集中于观测不确定性的来源及其影响解析等,但关于观测不确定性对径流情势特征指标变化趋势的影响研究较少。本文利用1971—2020年黄河水源涵养区5个水文站(黄河源区黄河沿、唐乃亥和兰州站,渭河咸阳站和伊洛河黑石关站)日径流观测序列,结合正态分布误差模型和趋势检验,检测了观测不确定性影响下五大径流情势特征(量级、事件发生频率、变率、历时和出现时间)16个指标的变化趋势,并采用不确定性宽度、指标斜率显著性变化的个数占比、变异系数和偏离程度量化了观测不确定性的影响。结果表明:①所有站点径流情势呈现低流量显著增加,高流量、平均流量、变率和历时显著减少的特征;黑石关站平均流量和高流量量级、变率和历时显著减少,频率显著增加;咸阳站低流量量级和出现时间显著增加,高流量量级、频率和变率显著减少;黄河源区低流量量级和高流量出现时间显著增加,低流量频率、高流量量级和变率显著减少。②观测不确定性对28.75%的径流情势特征指标的变化趋势影响明显,其中11.25%的指标变化趋势由显著变为不显著和17.5%的指标由不显著变为显著;对其他指标的变化趋势没有影响,其中变化趋势仍保持显著的指标占比为18.75%,变化趋势仍不显著的指标占比为52.50%。③观测不确定性对频率指标的变化趋势影响最大,影响次之为历时指标、变率指标和出现时间指标,而对量级指标的影响最小。 展开更多
关键词 观测不确定性 径流情势 正态分布误差模型 趋势检测 黄河水源涵养区
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面向碰撞假人质心及转动惯量测量设备开发研究 被引量:1
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作者 王凯 刘志新 +1 位作者 邢星飞 刘伟东 《机械设计》 北大核心 2025年第4期156-161,共6页
碰撞测试假人是衡量汽车被动安全性的重要仪器,其自身的质量特性参数(质量质心与转动惯量)的变化会导致其在试验过程中运动姿态的变化,最终影响试验结果的准确性。为了能够在多次试验之后及时掌握碰撞假人自身质量特性参数的变化,文中... 碰撞测试假人是衡量汽车被动安全性的重要仪器,其自身的质量特性参数(质量质心与转动惯量)的变化会导致其在试验过程中运动姿态的变化,最终影响试验结果的准确性。为了能够在多次试验之后及时掌握碰撞假人自身质量特性参数的变化,文中研究了适用于汽车碰撞假人组件的质量质心与转动惯量测试原理,依据此测试原理,设计了能够测量碰撞假人各部位总成质量特性参数的测量设备,并针对碰撞测试假人各部位总成的质量特性参数进行了测量分析。试验结果表明:所设计的测试设备能够以较小的误差完成碰撞假人总成的质量特性参数测量。 展开更多
关键词 测试误差 转动惯量 质心 碰撞假人
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Pt100铂电阻温度计电阻温度系数测试方法的研究 被引量:1
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作者 吕吉 《计量与测试技术》 2025年第6期130-134,共5页
电阻温度系数作为热电阻的关键参数,测量的准确度会直接影响其测温性能。针对目前计量测试领域缺乏统一的校准规范或测试方法,无法确保热电阻传感器测试结果的可靠性的问题,本文根据GB/T 6148-2005国家标准和JJG 229-2010检定规程,对其... 电阻温度系数作为热电阻的关键参数,测量的准确度会直接影响其测温性能。针对目前计量测试领域缺乏统一的校准规范或测试方法,无法确保热电阻传感器测试结果的可靠性的问题,本文根据GB/T 6148-2005国家标准和JJG 229-2010检定规程,对其测试方法进行了研究。同时,通过搭建测量装置,使用Pt100铂电阻温度计在(0~100)℃范围内进行实验测试,比较不同数据处理方法的计算结果,并进行误差分析。 展开更多
关键词 Pt100铂电阻温度计 电阻温度系数(TCR) 测试方法 误差分析
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结构强度试验校准值影响因素分类研究与应用
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作者 韩涛 常亮 +1 位作者 聂小华 段世慧 《工程与试验》 2025年第3期108-110,共3页
针对结构强度试验传感器校准问题,提出了一种校准过程影响因素分类方法。考虑校准流程中各环节可能对误差造成的影响,对现有主客观因素分类方法进行了细化,有效提高了分类对故障诊断的精确识别,提高了排查效率,达到了流程优化的目的。... 针对结构强度试验传感器校准问题,提出了一种校准过程影响因素分类方法。考虑校准流程中各环节可能对误差造成的影响,对现有主客观因素分类方法进行了细化,有效提高了分类对故障诊断的精确识别,提高了排查效率,达到了流程优化的目的。该分类方法可以指导校准故障诊断系统的优化升级,所提分类方法便于故障分类识别,提高了一次性排故成功率,具有一定的实际应用价值。 展开更多
关键词 结构强度试验 传感器 校准误差 影响因素
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PBRTQC方法在凝血质量控制中的应用
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作者 王文静 赵丹彤 +1 位作者 马捷 于艳华 《标记免疫分析与临床》 2025年第5期1018-1022,共5页
目的探讨基于患者数据的实时质量控制(patient-based real-time quality control,PBRTQC)方法在凝血检测质量管理中的应用,优化参数设置,并评估不同PBRTQC算法对凝血指标的误差检测性能。方法收集首都医科大学附属北京佑安医院2023.4-20... 目的探讨基于患者数据的实时质量控制(patient-based real-time quality control,PBRTQC)方法在凝血检测质量管理中的应用,优化参数设置,并评估不同PBRTQC算法对凝血指标的误差检测性能。方法收集首都医科大学附属北京佑安医院2023.4-2024.4期间凝血检测数据,包括凝血酶原时间(prothrombin time,PT)、活化部分凝血活酶时间(activated partial thromboplastin time,APTT)、纤维蛋白原(fibrinogen,FIB)及D-二聚体(D-dimer,D-D)4项指标。采用移动中位数(moving median,MM)、移动均值(simple moving average,SMA)、加权移动均值(weighted moving average,WMA)和加权移动均值(exponentially weighted moving average,EWMA)4种PBRTQC算法,对不同参数组合进行穷举计算,并通过设定预期假阳性率(desired false positive rate,DFPR)、控制限(truncation limit,TL)、步长及加权系数等参数,优化PBRTQC方案。利用训练集和验证集评估PBRTQC方案的误差检测性能,并在真实世界数据中进行应用验证。结果PBRTQC方法对系统误差的检测表现优于传统质控方法,尤其对负误差的检测更为敏感。PT适用于WMA算法,可快速检测负误差并将假阳性率控制在1%以下;APTT和FIB采用EWMA算法,在适应性和灵敏度方面表现更优;D-D由于随机误差较大,WMA算法表现出较强的抗干扰能力。最终优化参数在验证集上的假阳性率(false positive rate,FPR)、假阴性率(false negative rate,FNR)、及时性(average number of patient samples to error detection,ANPed)表现稳定,能够有效识别仪器漂移、试剂批次变化等质量问题。结论本研究优化了PBRTQC方法在凝血检测中的应用,提高了误差监测的灵敏度和稳定性,为实验室质量控制提供了新的技术手段。未来研究可进一步拓展数据来源,优化算法,并探索PBRTQC在更广泛的临床检测项目中的应用。 展开更多
关键词 基于患者数据的实时质量控制(PBRTQC) 凝血检测 误差监测 参数优化 质量管理
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小样本下的多重假设检验在仿真确认中的应用
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作者 孙慧玲 马天宇 +1 位作者 艾小川 宋曦阳 《海军工程大学学报》 北大核心 2025年第5期29-34,64,共7页
针对仿真输出的样本量为海量、高维数据,而验证性数据是小样本这一特性,将多重假设检验方法进行了改进,并应用于仿真确认研究中。首先,基于验证性数据是离散型小样本,建立了p-value模型来估计小样本数据的p-值;然后,改进了多重假设检验... 针对仿真输出的样本量为海量、高维数据,而验证性数据是小样本这一特性,将多重假设检验方法进行了改进,并应用于仿真确认研究中。首先,基于验证性数据是离散型小样本,建立了p-value模型来估计小样本数据的p-值;然后,改进了多重假设检验中估计正确原假设个数m 0的方法,建立了M-power模型来评估检验功效,给出了M-power模型中相关指标的求解方法;最后,以悬浮式深弹拦截鱼雷仿真确认为例,通过建模仿真方法对拦截概率与报警舷角、报警距离的关系进行了定量分析,并用改进方法对仿真进行了确认。仿真结果表明:与原多重假设检验相比,改进后的方法犯检验第二类错误的概率更低,且检验功效高于原方法。 展开更多
关键词 仿真确认 小样本 多重假设检验 检验功效 第二类错误
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基于大模型启发式提问的学生元认知能力提升研究 被引量:1
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作者 吴雯 任飞霏 《心理科学》 北大核心 2025年第4期985-996,共12页
元认知能力指个体对自身思维过程的察觉、反思与调节,有助于学习者自主监测学习过程。启发式提问被认为是提升元认知的有效手段,但传统课堂中实施难度大,结合大语言模型后仍面临模板化、缺乏逻辑递进与评估机制不足等问题。为此构建了... 元认知能力指个体对自身思维过程的察觉、反思与调节,有助于学习者自主监测学习过程。启发式提问被认为是提升元认知的有效手段,但传统课堂中实施难度大,结合大语言模型后仍面临模板化、缺乏逻辑递进与评估机制不足等问题。为此构建了基于错因的启发式问题库,并设计多种策略引导大模型提问,推动其从“问题百科”转变为“提问导师”。同时引入人工与大模型双重评分机制评估提问效果。结果显示:(1)基于错因的问题库能有效提升学习者的元认知能力;(2)多种提问策略中,半自由提问策略(即基于错因提问,其余自由发挥)表现优于完全自由或严格策略;(3)通过多维度评价,证明提出的智能启发式提问机制能有效促进学习者元认知发展。 展开更多
关键词 元认知能力 启发式提问 大语言模型 错因分析 提问策略 人机共测
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