Application of Total Error Strategy in Validation of Affordable and Accessible UV-Visible Spectrophotometric Methods for Quality Control of Poor Medicines

In the framework of fighting against the poor quality medicines sold in developing countries using classical analytical methods easily accessible in those countries, four UV-Visible spectrophotometric methods for one antimalarial (quinine) and two antibiotics (amoxicillin and metronidazole) have been developed and validated according to the total error strategy using the accuracy profiles as a decision tool. The dosing range was 2 - 10 μg/mL (for quinine sulfate in tablet), 4 - 12 μg/mL (for quinine bichlorhydrate in oral drop-metronidazole benzaote in oral suspension) and 15 - 35 μg/mL (for amoxicillin trihydrate in capsule). The validated methods were then applied in determining the content of some analogous medicines sold in the Democratic Republic of Congo. Thus, the proposed UV-Visible spectrophotometric methods are simple and suitable to quantify quinine, amoxicillin and metronidazole in different pharmaceutical forms.

Use of Total Precipitable Water Classification of A Priori Error and Quality Control in Atmospheric Temperature and Water Vapor Sounding Retrieval

This study investigates the use of dynamic a priori error information according to atmospheric moistness and the use of quality controls in temperature and water vapor profile retrievals from hyperspectral infrared （IR） sounders. Temperature and water vapor profiles are retrieved from Atmospheric InfraRed Sounder （AIRS） radiance measurements by applying a physical iterative method using regression retrieval as the first guess. Based on the dependency of first-guess errors on the degree of atmospheric moistness, the a priori first-guess errors classified by total precipitable water （TPW） are applied in the AIRS physical retrieval procedure. Compared to the retrieval results from a fixed a priori error, boundary layer moisture retrievals appear to be improved via TPW classification of a priori first-guess errors. Six quality control （QC） tests, which check non-converged or bad retrievals, large residuals, high terrain and desert areas, and large temperature and moisture deviations from the first guess regression retrieval, are also applied in the AIRS physical retrievals. Significantly large errors are found for the retrievals rejected by these six QCs, and the retrieval errors are substantially reduced via QC over land, which suggest the usefulness and high impact of the QCs, especially over land. In conclusion, the use of dynamic a priori error information according to atmospheric moistness, and the use of appropriate QCs dealing with the geographical information and the deviation from the first-guess as well as the conventional inverse performance are suggested to improve temperature and moisture retrievals and their applications.

Total Sensitivity Index Calculation of Tool Requirement Model via Error Propagation Equation

A new and convenient method is presented to calculate the total sensitivity indices defined by variance-based sensitivity analysis. By decomposing the output variance using error propagation equations, this method can transform the ＂double-loop＂ sampling procedure into ＂single-loop＂ one and obviously reduce the computation cost of analysis. In contrast with Sobors and Fourier amplitude sensitivity test （FAST） method, which is limited in non-correlated variables, the new approach is suitable for correlated input variables. An application in semiconductor assembling and test manufacturing （ATM） factory indicates that this approach has a good performance in additive model and simple non-additive model.

基于ACPI的磁浮球系统控制方法

针对传统控制算法在解决磁浮球系统中存在高度非线性特性、参数摄动以及外部扰动的技术局限性问题,提出一种基于自耦PID(Auto-coupling PID, ACPID)控制理论的磁浮球系统控制方法。首先根据电磁力在平衡点附近进行1阶Taylor展开,结合电磁线圈的动态模型,形成以电压为控制输入的磁浮球位置动态系统。在磁浮球动力学模型的基础上,再将不确定高阶项、电磁线圈的未知电流动态以及外部未知有界扰动定义为总扰动,从而可将一个非线性不确定磁浮球系统映射为一个2阶线性扰动系统。其次,基于ACPID控制量纲匹配构造的误差函数,可将2阶线性扰动系统映射为1阶线性系统,进而构建一个在总扰动反相激励下的闭环受控误差系统,据此设计了基于速度因子的磁浮球位置通道控制器,建立磁浮球位置控制系统并进行鲁棒稳定性分析,理论证明了ACPI方法的有效性。最后与国外现有较为先进的控制方法进行对比仿真,分别进行了方波跟踪实验、正弦跟踪实验、抗扰动实验以及鲁棒性实验。与NTSMC+GPIO方法相比,在方波跟踪实验中ACPI控制系统的响应速度提升了50%,ITAE值降低了82%,RMSE值降低了22.4%,其他仿真实验下的控制性能也有明显的提升。研究结果表明,ACPI控制策略不仅可以实现在超调量较小的情况下具备较快的响应速度、较高的控制精度、较强的抗扰动能力以及较好的鲁棒性,而且控制器结构简单、计算量小,在磁浮球控制系统领域具有一定的应用前景。

超声全聚焦成像的裂纹类缺陷定量误差分析

虽然超声全聚焦成像(total focusing method,TFM)具有直观显示裂纹特征的明显优势,但通过TFM图像进行裂纹定量时不可避免地出现测量误差。该文采用模拟与实验对比的方式,分析TFM技术的裂纹定量误差。从超声波波长对缺陷深度的影响规律入手,分析和研究裂纹长度和取向的全聚焦图像测量误差原因。最后,通过模拟实验对比的方式验证裂纹定量误差。研究结果表明,裂纹上、下尖端的测量深度比实际深度均有所下沉,但两者下沉的深度基本相同,相差在0.6 mm以内,裂纹长度的测量误差范围为0~1 mm,带取向裂纹的取向测量误差基本保持在3°以内。因此,上、下尖端在深度上的测量误差对裂纹长度和取向的影响极小。经实验验证,裂纹深度、长度及取向误差的结论与模拟的结论一致。

六西格玛理论用于两台生化检测系统的比较

目的探讨六西格玛(6σ)理论用于两台生化检测系统的比较。方法收集2022年7月1日至12月31日盘锦辽油宝石花医院检验科生化分析仪上32个项目的室内质控检测结果,通过两台仪器的室内质控数据计算每个项目的西格玛(σ)值和偏倚(bias),用传统比对方法计算每个项目的bias,采用SPSS 26.0统计软件对室内质控数据计算的σ值和bias与传统方法的bias进行Pearson相关性分析。结果32个项目中有15个项目σ值≥6,无需进行改进,17个项目通过计算质量目标指数(QGI)的结果进行改进,其中15个项目需要改进精密度,2个项目需要改进精密度和正确度,将需要改进的17个项目的计算变异系数(CV)与实验室允许CV比较,结果显示均小于允许CV,2台仪器比对通过,对于传统方法,两台机器的bias也在标准范围之内,2个质控水平的σ值与传统方法的bias之间均没有显著相关性(P=0.754、0.779),而2个质控水平的bias与传统方法的bias之间呈正相关(P=0.041、0.029)。结论应用质控数据计算σ值及QGI进行不同检测系统间的比对是一种比较方便、可操作性强的方法,可以随时监测实验室内不同检测系统间的可比性,并对传统的比对方法进行补充。

Application of Sigma Metric Analysis to Evaluate the Performance of the Biochemistry Analytical System in a Medical Biology Laboratory in Côte d’Ivoire

Introduction: The Six Sigma methodology is an opportunity for a better understanding of the performance of analytical methods and for a better adaptation of the quality control management policy of the medical biology laboratory. Using the sigma metric, this study assessed the performance of the Biochemistry analytical system of a medical biology laboratory in Côte d'Ivoire. Methods: Six Sigma methodology was applied to 3 analytes (alanine aminotransferase, glucose and creatinine). Performance indicators such as measurement imprecision and bias were determined based on the results of internal and external quality controls. The sigma number was calculated using the total allowable error values proposed by Ricos et al. Results: For both control levels, ALT had a sigma number greater than 6 (7.6 for normal control and 7.9 for pathological control). However, low sigma numbers, less than or equal to 2 for creatinine (1.4 for normal control and 2 for pathological control) and less than 1 for glucose were found. Conclusion: This study revealed good analytical performance of ALT from the point of view of 6 sigma analysis. However, modifications to the overall quality control procedure for glucose and creatinine are needed to improve their analytical performance. The study should be extended to the entire laboratory’s analytes in order to modify the strategies of quality control procedures based on metric analysis for an overall improvement in analytical performance.

基于全站仪法塔尺刻线示值误差的研究与试验

为避免塔尺刻线示值误差在检测时中间格挡的影响,本文结合高度卡尺和全站仪,对其检测方法进行探讨,并分别建立数学模型进行试验。试验表明:塔尺两端刻线示值误差未超过-0.20mm,且全量程刻线示值误差均小于0,整体刻线值较小,在3750mm刻线处的示值误差最大为-1.40mm,满足JJG 8-1991《水准标尺检定规程》中全长(5m)误差小于±3.0mm要求。

扫描雷达未知天线方向图误差下的稀疏目标角超分辨重建方法

扫描雷达角超分辨技术是基于目标与天线方向图的关系,采用解卷积方法获取超越实波束的角分辨能力。目前的角超分辨方法大都是基于理想的无畸变天线方向图,未考虑实际过程中方向图的变化。然而,由于雷达天线罩、天线测量误差与平台非理想运动等因素的影响,天线方向图在实际中往往存在未知的误差,会导致目标分辨能力下降,甚至产生虚假目标。针对此问题,该文提出一种机载扫描雷达未知天线方向图误差下的角超分辨成像方法。首先,基于总体最小二乘(TLS)准则,该文考虑了方向图误差矩阵的影响,导出了相应的目标函数;其次,基于交替迭代的求解思路,利用迭代重加权优化方法实现了目标函数求解;最后,针对算法超参数选取,引入了一种自适应参数选取方法。仿真与实测结果表明,该文方法能实现未知天线误差条件下的超分辨重建,进一步提升了超分辨算法的稳健性。

尿量仪校准方法的研究

在尿量仪质量控制方面,目前国内并没有相应的国家标准和计量标准。本文主要介绍了尿量仪的组成和用途,针对目前临床在用设备,研究了尿量仪的校准方法,并进行了验证实验。依据此方法制定了《尿量仪国家校准规范》,已通过全国临床医学计量技术委员会专家评审,即将颁布。此规范的实施将为开展相应的质量控制工作提供技术依据,希望通过质量控制,确保尿量仪设备良好运行,有效提高医疗安全。

全站仪轴系误差的解析几何模型体现与检定原理

全站仪轴系误差会持续影响观测结果,是影响全站仪测角精度的关键因素,在实际应用中甚至会因为观测条件的不同而产生破坏性影响。本文通过建立三轴结构解析几何模型,对轴系误差进行定量分析,并结合检定规范阐述了轴系误差的检定原理,为研究轴系误差的产生与计算轴系误差提供了新的途径和思路,也为计量检定过程提供了有效参考。

自动电位滴定法测定无糖饮料中的总酸含量

基于自动电位滴定法分析测定了无糖饮料中的总酸含量,实验结果显示,当称取无糖气泡水50.0051 g、无糖茶饮品50.0227 g、无糖果汁50.0522 g时,其总酸含量分别为3.89,3.58,4.12 g/kg。该方法的加标回收率在94.0%~106.0%,RSD均小于2%,表明该方法准确度高、精密度好、可行性高。本文也简单探讨了测定过程中误差的来源及减免方法,其中误差主要来源于NaOH标准溶液的配制、无糖饮料待测试液的滴定分析及分析测试人员的操作。

平均轨迹误差、血清内毒素与CR假体全膝关节置换术后早期疗效的关系

目的分析平均轨迹误差、血清内毒素与后交叉韧带保留型(CR)假体全膝关节置换术(TKA)后早期疗效的关系。方法收集2021年8月至2023年6月于邯郸市第一医院拟行TKA的膝骨关节炎(KOA)患者为研究对象,术后3个月时采用美国膝关节协会(AKS)评分和膝关节功能评分表(HSS)评分评估患者TKA后的早期疗效,同时收集患者基线资料,术后1、2、3个月时测定患者本体感觉(平均轨迹误差)、血清内毒素水平。分析平均轨迹误差、血清内毒素与患者CR假体TKA后早期疗效的关系。结果术后3个月时,100例患者中AKS评分<70分23例(23.00%),HSS评分<70分26例(26.00%)。重复测量方差分析显示,不同AKS评分患者及不同HSS评分患者血清内毒素水平、平均轨迹误差均存在组间效应、时间效应和交互效应(P<0.05),故进一步单独效应分析。两组术后2、3个月时血清内毒素水平、平均轨迹误差均低于术后1个月时(P<0.05)。多变量方差分析显示,AKS评分<70分者术后1、2、3个月时的血清内毒素水平、平均轨迹误差均高于AKS评分≥70分者(P<0.05),HSS评分<70分者术后1、2、3个月时的血清内毒素水平、平均轨迹误差均高于HSS评分≥70分者(P<0.05)。Pearson相关分析显示,平均轨迹误差、血清内毒素水平与AKS评分、HSS评分均呈负相关(r=-0.285~-0.206,P<0.05)。多因素Logistic回归分析显示,平均轨迹误差、血清内毒素是CR假体TKA后早期AKS评分≥70分或HSS评分≥70分的影响因素(P<0.05)。结论CR假体TKA后患者早期疗效与平均轨迹误差、血清内毒素存在一定关系。

耳穴贴压联合眼周经皮穴位电刺激在6~12岁儿童轻度近视中的应用研究

目的观察耳穴贴压联合眼周经皮穴位电刺激在6~12岁儿童轻度近视中的应用效果。方法采用随机数字表法将2022年11月—2023年4月在石家庄市某小学的132例轻度近视儿童平均分为3组,分别为耳穴贴压组、眼周经皮穴位电刺激组、联合组,每组44例。3组患儿均给予常规护理,在此基础上,耳穴贴压组给予耳穴贴压治疗,眼周经皮穴位电刺激组给予眼周经皮穴位电刺激治疗,联合组给予耳穴贴压联合眼周经皮穴位电刺激治疗。3组患儿干预疗程均为每4周1个疗程,1个疗程后暂停1周,再进行第2个疗程,共2个疗程。比较3组患儿治疗前、治疗1个疗程后、治疗2个疗程后的裸眼远视力、屈光度、调节灵敏度及眼局部症状总积分,观察其对轻度近视儿童的治疗效果。结果干预结束后,共脱落8例患儿,最终纳入124例,分别为耳穴贴压组41例,眼周经皮穴位电刺激组41例,联合组42例。3组患儿治疗前的裸眼远视力、屈光度、调节灵敏度及眼局部症状总积分经比较,差异均无统计学意义(P>0.05)。3组患儿第1疗程及第2疗程干预结束后的裸眼远视力、屈光度、调节灵敏度及眼局部症状总积分经比较,差异有统计学意义(P<0.05)。组间比较3组患儿的裸眼远视力、屈光度及眼局部症状总积分,差异具有统计学意义(P<0.05),其中联合组与耳穴贴压组、眼周经皮穴位电刺激组相比差异具有统计学意义(P<0.05)。结论3种干预措施均可有效改善儿童轻度近视患儿的裸眼远视力、屈光度、调节灵敏度及眼局部症状,对轻度近视儿童具有治疗和防控近视进展的作用,疗效良好,且联合治疗对于儿童轻度近视的治疗及防控效果优于单一的耳穴贴压治疗或眼周经皮穴位电刺激治疗。

Error model identification of inertial navigation platform based on errors-in-variables model

Because the real input acceleration cannot be obtained during the error model identification of inertial navigation platform, both the input and output data contain noises. In this case, the conventional regression model and the least squares （LS） method will result in bias. Based on the models of inertial navigation platform error and observation error, the errors-in-variables （EV） model and the total least squares （TLS） method axe proposed to identify the error model of the inertial navigation platform. The estimation precision is improved and the result is better than the conventional regression model based LS method. The simulation results illustrate the effectiveness of the proposed method.

Error Model of Curves in GIS and Digitization Experiment

A stochastic error process of curves is proposed as the error model to describe the errors of curves in GIS. In terms of the stochastic process, four characteristics concerning the local error of curves, namely, mean error function, standard error function, absolute error function, and the correlation function of errors , are put forward. The total error of a curve is expressed by a mean square integral of the stochastic error process. The probabilistic meanings and geometric meanings of the characteristics mentioned above are also discussed. A scan digitization experiment is designed to check the efficiency of the model. In the experiment, a piece of contour line is digitized for more than 100 times and lots of sample functions are derived from the experiment. Finally, all the error characteristics are estimated on the basis of sample functions. The experiment results show that the systematic error in digitized map data is not negligible, and the errors of points on curves are chiefly dependent on the curvature and the concavity of the curves.

22个内分泌检验项目允许总误差、允许不精密度和允许偏移的设定

目的设定22个内分泌检验项目允许总误差(TEa)、允许不精密度[用变异系数(CV)表示]和允许偏移(Bias),以推荐相关项目的性能规范。方法收集2020—2022年国家卫生健康委临床检验中心内分泌项目室间质量评价(EQA)和室内质量控制(IQC)数据。根据意大利米兰会议最新确定的性能规范设定模式,基于生物学变异(BV)和当前技术水平模式导出性能规范。对于有BV数据的检验项目,将EQA数据的“百分差值”、IQC数据的当月在控“CV”与基于BV导出的3个水平评价标准进行比较,计算所有批号质控品的百分差值通过率和CV通过率,以通过率达到80%为该水平质控品的性能规范满足该项目推荐性能规范要求。对于无BV数据或基于BV导出的3个水平性能规范均无法作为推荐标准的检验项目,基于当前技术水平导出推荐TEa和CV,再导出允许Bias。结果22个内分泌检验项目推荐的TEa/允许CV分别为:游离三碘甲状腺原氨酸18.9%/6.5%,总三碘甲状腺原氨酸17.4%/7.1%,游离甲状腺素25.0%/6.2%,总甲状腺素20.0%/7%,促甲状腺激素24.6%/8.9%,皮质醇26.3%/8.2%,雌二醇26.0%/7.5%,卵泡刺激素21.2%/6.2%,黄体生成素25.0%/6.8%,孕酮26.2%/9.3%,催乳素18.7%/7.4%,睾酮16.5%/6.3%,C-肽20.8%/8.3%,叶酸29.5%/8.9%,胰岛素25.0%/6.4%,甲状腺球蛋白28.2%/8.0%,甲状旁腺激素30.0%/11.8%,醛固酮21.4%/9.2%,硫酸脱氢表雄酮25.0%/7.5%,维生素B1225.0%/7.5%,生长激素25.0%/7.0%,促肾上腺皮质激素27.4%/9.1%。结论设定的22个内分泌检验项目的TEa、允许CV和允许Bias可推荐作为符合中国临床实验室当前技术水平的性能规范。

The Accuracy of Initial Bone Cutting in Total Knee Arthroplasty

Background: The aim of this study was to evaluate the accuracy of initial bone cutting of the distal femur and the proximal tibia in TKA using an image-free navigation system. Methods: From February 2006 to March 2013, we evaluated 60 knees in 50 patients using an image-free navigation system (Navigation: Stryker Navigation Cart System;Software: Stryker Knee Navigation;Ver2.0: Stryker Orthopaedics US NJ Mahwah). First, we measured the angle shown by the navigation system before cutting, at the time we set the jig. Second, we measured the angles shown by navigation after the bone was cut using the jig. Then, we compared these two angles for each patient to determine the bone cutting error. Results: In the distal femur, 37 of 60 knees were cut in an extended position in the sagittal plane, and 26 of 60 knees were cut in a varus in the coronal plane. In the proximal tibia, 29 of 60 knees were cut with decreased posterior slope in the sagittal plane, and 26 of 60 knees were cut in a valgus. Conclusions: In this study, the distal femur tended to be cut in an extended and a varus position and the proximal tibia did with decreased posterior slope and in a valgus position after initial bone cutting. It is necessary to note the initial cutting error in TKA. Since cutting errors affect postoperative outcome, we should cut bones several times. And as the reasons of the cause of the error, we propose new reason that cutting bone is not parallel with accuracy to AP axis.

Accuracy Assessment and Guidelines for Manual Traffic Counts from Pre-Recorded Video Data

Traffic count is the fundamental data source for transportation planning, management, design, and effectiveness evaluation. Recording traffic flow and counting from the recorded videos are increasingly used due to convenience, high accuracy, and cost-effectiveness. Manual counting from pre-recorded video footage can be prone to inconsistencies and errors, leading to inaccurate counts. Besides, there are no standard guidelines for collecting video data and conducting manual counts from the recorded videos. This paper aims to comprehensively assess the accuracy of manual counts from pre-recorded videos and introduces guidelines for efficiently collecting video data and conducting manual counts by trained individuals. The accuracy assessment of the manual counts was conducted based on repeated counts, and the guidelines were provided from the experience of conducting a traffic survey on forty strip mall access points in Baton Rouge, Louisiana, USA. The percentage of total error, classification error, and interval error were found to be 1.05 percent, 1.08 percent, and 1.29 percent, respectively. Besides, the percent root mean square errors (RMSE) were found to be 1.13 percent, 1.21 percent, and 1.48 percent, respectively. Guidelines were provided for selecting survey sites, instruments and timeframe, fieldwork, and manual counts for an efficient traffic data collection survey.

Total least-squares EIO model,algorithms and applications

A functional model named EIO(Errors-In-Observations) is proposed for general TLS(total least-squares)adjustment. The EIO model only considers the correction of the observation vector, but doesn't consider to correct all elements in the design matrix as the EIV(Errors-In-Variables) model does, furthermore, the dimension of cofactor matrix is much smaller. Iterative algorithms for the parameter estimation and their precise covariance matrix are derived rigorously, and the computation steps are also presented. The proposed approach considers the correction of the observations in the coefficient matrix, and ensures their agreements in every matrix elements. Parameters and corrections can be solved at the same time.An approximate solution and a precise solution of the covariance matrix can be achieved by corresponding algorithms. Applications of EIO model and the proposed algorithms are demonstrated with several examples. The results and comparative studies show that the proposed EIO model and algorithms are feasible and reliable for general adjustment problems.