Adaptive Robust Servo Control for Vertical Electric Stabilization System of Tank and Experimental Validation

A tracking stability control problem for the vertical electric stabilization system of moving tank based on adaptive robust servo control is addressed.This paper mainly focuses on two types of possibly fast timevarying but bounded uncertainty within the vertical electric stabilization system:model parameter uncertainty and uncertain nonlinearity.First,the vertical electric stabilization system is constructed as an uncertain nonlinear dynamic system that can reflect the practical mechanics transfer process of the system.Second,the dynamical equation in the form of state space is established by designing the angular tracking error.Third,the comprehensive parameter of system uncertainty is designed to estimate the most conservative effects of uncertainty.Finally,an adaptive robust servo control which can effectively handle the combined effects of complex nonlinearity and uncertainty is proposed.The feasibility of the proposed control strategy under the practical physical condition is validated through the tests on the experimental platform.This paper pioneers the introduction of the internal nonlinearity and uncertainty of the vertical electric stabilization system into the settlement of the tracking stability control problem,and validates the advanced servo control strategy through experiment for the first time.

Application of SWAT Model to the Olifants Basin: Calibration, Validation and Uncertainty Analysis

The application of the Soil and Water Assessment Tool (SWAT) to the Olifants Basin in South Africa was the focus of our study with emphasis on calibration, validation and uncertainty analysis. The Basin was discretized into 23 sub-basins and 226 Hydrologic Response Units (HRUs) using 3 arc second (90 m × 90 m) pixel resolution SRTM DEM with stream gauge B7H015 as the Basin outlet. Observed stream flow data at B7H015 were used for model calibration (1988-2001) and validation (2002-2013) using the split sample approach. Relative global sensitivity analysis using SUFI-2 algorithm was used to determine sensitive parameters to stream flow for calibration of the model. Performance efficiency of the Olifants SWAT model was assessed using Nash-Sutcliffe (NSE), coefficient of determination (R2), Percent Bias (PBIAS) and Root Mean Square Error-Observation Standard deviation Ratio (RSR). Sensitivity analysis revealed in decreasing order of significance, runoff curve number (CN2), alpha bank factor (ALPHA_BNK), soil evaporation compensation factor (ESCO), soil available water capacity (SOIL_AWC, mm H2O/mm soil), groundwater delay (GW_ DELAY, days) and groundwater “revap” coefficient (GW_REVAP) to be the most sensitive parameters to stream flow. Analysis of the model during the calibration period gave the following statistics;NSE = 0.88;R2 = 0.89;PBIAS = -11.49%;RSR = 0.34. On the other hand, statistics during the validation period were NSE = 0.67;R2 = 0.79;PBIAS = -20.69%;RSR = 0.57. The observed statistics indicate the applicability of the SWAT model in simulating the hydrology of the Olifants Basin and therefore can be used as a Decision Support Tool (DST) by water managers and other relevant decisions making bodies to influence policy directions on the management of watershed processes especially water resources.

Internal Validity Index for Fuzzy Clustering Based on Relative Uncertainty

Unsupervised clustering and clustering validity are used as essential instruments of data analytics.Despite clustering being realized under uncertainty,validity indices do not deliver any quantitative evaluation of the uncertainties in the suggested partitionings.Also,validity measures may be biased towards the underlying clustering method.Moreover,neglecting a confidence requirement may result in over-partitioning.In the absence of an error estimate or a confidence parameter,probable clustering errors are forwarded to the later stages of the system.Whereas,having an uncertainty margin of the projected labeling can be very fruitful for many applications such as machine learning.Herein,the validity issue was approached through estimation of the uncertainty and a novel low complexity index proposed for fuzzy clustering.It involves only uni-dimensional membership weights,regardless of the data dimension,stipulates no specific distribution,and is independent of the underlying similarity measure.Inclusive tests and comparisons returned that it can reliably estimate the optimum number of partitions under different data distributions,besides behaving more robust to over partitioning.Also,in the comparative correlation analysis between true clustering error rates and some known internal validity indices,the suggested index exhibited the highest strong correlations.This relationship has been also proven stable through additional statistical acceptance tests.Thus the provided relative uncertainty measure can be used as a probable error estimate in the clustering as well.Besides,it is the only method known that can exclusively identify data points in dubiety and is adjustable according to the required confidence level.

聚类不确定性的三支决策方法综述

由于数据有复杂性、多样性和不确定性的特点,聚类通常存在不确定性,这种不确定性是指聚类结果的不一致性,从而影响分析的准确性,而通过三支决策方法构建不确定域,对不确定域进行延迟决策,能够带来一系列的优势。近些年来,这个研究热点涌现许多重要的工作。对聚类不确定的三支决策方法模型和研究方向进行介绍,按照三支聚类构建过程中遇到的问题进行总结。首先,给出三支聚类的表现形式。其次,分别阐述如何构建三支聚类的核心域和边界域,如何确定阈值,如何设计有效性指标,并介绍其中具有代表性的工作。最后,对聚类不确定的三支决策方法进行总结,并展望未来的研究方向。

A Survey on an Emerging Safety Challenge for Autonomous Vehicles:Safety of the Intended Functionality

As the complexity of autonomous vehicles(AVs)continues to increase and artificial intelligence algorithms are becoming increasingly ubiquitous,a novel safety concern known as the safety of the intended functionality(SOTIF)has emerged,presenting significant challenges to the widespread deployment of AVs.SOTIF focuses on issues arising from the functional insufficiencies of the AVs’intended functionality or its implementation,apart from conventional safety considerations.From the systems engineering standpoint,this study offers a comprehensive exploration of the SOTIF landscape by reviewing academic research,practical activities,challenges,and perspectives across the development,verification,validation,and operation phases.Academic research encompasses system-level SOTIF studies and algorithm-related SOTIF issues and solutions.Moreover,it encapsulates practical SOTIF activities undertaken by corporations,government entities,and academic institutions spanning international and Chinese contexts,focusing on the overarching methodologies and practices in different phases.Finally,the paper presents future challenges and outlook pertaining to the development,verification,validation,and operation phases,motivating stakeholders to address the remaining obstacles and challenges.

原子荧光分光光度法测定纺织品中重金属砷的方法验证及测量不确定度评定

文章采用原子荧光分光光度法测定纺织品中重金属元素砷的含量,研究与分析方法的线性范围、检出限、定量限、正确度和精密度,进行了不确定度的评定。实验结果表明,该方法的检出限为0.007 mg/kg,定量限为0.017 mg/kg,精密度<10%,相对标准不确定度为2.4%,实验室能够满足标准方法的检测要求。

Measurement uncertainty in pharmaceutical analysis and its application

The measurement uncertainty provides complete information about an analytical result. This is very important because several decisions of compliance or non-compliance are based on analytical results in pharmaceutical industries. The aim of this work was to evaluate and discuss the estimation of uncertainty in pharmaceutical analysis. The uncertainty is a useful tool in the assessment of compliance or non-compliance of in-process and final pharmaceutical products as well as in the assessment of pharmaceutical equivalence and stability study of drug products.

Fuzzy Clustering Validity for Spatia Data

The validity measurement of fuzzy clustering is a key problem. If clustering is formed, it needs a kind of machine to verify its validity. To make mining more accountable, comprehensible and with a usable spatial pattern, it is necessary to first detect whether the data set has a clustered structure or not before clustering. This paper discusses a detection method for clustered patterns and a fuzzy clustering algorithm, and studies the validity function of the result produced by fuzzy clustering based on two aspects, which reflect the un-certainty of classification during fuzzy partition and spatial location features of spatial data, and proposes a new validity function of fuzzy clustering for spatial data. The experimental result indicates that the new validity function can accurately measure the validity of the results of fuzzy clustering. Especially, for the result of fuzzy clustering of spatial data, it is robust and its classification result is better when compared to other indices.

Psychometric properties of the Chinese version of the Parent Perception of Uncertainty Scale(PPUS)among parents of children with cancer diagnosis

Objective:Parents of children diagnosed with cancer often experience high levels of illness uncertainty.This study evaluated the psychometric properties of the Chinese Version of the Parent Perception of Uncertainty Scale for Childhood Cancer(PPUS-CC)in China's Mainland.Methods:Exploratory factor analysis(EFA)and confirmatory factor analysis(CFA)were performed using study population of 420 parents.The participants were also given the social support questionnaire and assessed using the Self-Rating Anxiety Scale,Zarit Burden Interview,and Self-Rating Depression Scale to test the association with PPUS-CC and obtain the cut-off of the scale.Results:The Chinese version of PPUS-CC includes 14 items,and two factors were extracted by EFA,which could explain the 54.56%variances.The Cronbach'sαof two factors ranged from 0.830 to 0.877.The dimensions of PPUS-CC show statistical association with other scales,and the cut-off is 42.5.Conclusion:The Chinese version of PPUS-CC,as a reliable,valid,and easy-to-use clinical tool,can be adapted in clinical settings as a screening tool to recognize parents with high-risk psychological problems.

计算流体力学验证与确认研究进展

计算流体力学(CFD)在重大工程领域发挥了日益重要的作用,可信度是制约其进一步大规模工程应用的关键因素.国内外普遍认同验证与确认是CFD可信度评价和保证的必经途径.通过系统的验证与确认,可以有效识别代码中潜在的编程错误,保证数值求解的可靠性,客观评价模型在预期用途内的适用性,在必要时提高模型的预测能力.本文围绕着什么是验证与确认,怎么做验证与确认这两个核心问题,从基本概念、实施流程、主要方法、标模试验和平台工具等角度介绍了国内外在CFD验证与确认领域的研究进展,重点对误差估计和不确定度量化方法展开介绍.文章最后对现阶段验证与确认研究解决实际工程问题的不足进行了评述和总结,对未来重点研究方向进行了展望.

Uncertainty Evaluation of Boar Fresh Semen Quality

According to JJF1059.2-2012 and CNAS-GL06, the measurement uncertainty of four indicators （semen volume, sperm motility and validity, progressive motility, abnormal sperm percentage） of boar fresh semen, as well as its influencing factors, was analyzed. The results showed that the measurement uncertainty of semen volume and progressive motility caused by inspectors was low, and their measurement results reliability was high. There were small differences in measurement results of semen volume and progressive motility among inspectors. However, the measurement uncertainty of sperm motility and abnormal sperm percentage was relatively large, and great differences were found among different inspectors. Therefore, the training of inspectors＇ measuring sperm motility and abnormal sperm percentage should be strengthened, and the comparison of measurement results among inspectors should be performed in the future.

Titration Method Validation of Live Vaccines against Infectious Bursal Disease

Validating a method of analysis goes through different steps, which aims at testing the normality of measurements distribution, estimating the uncertainty of the components of a measurement （i.e., accuracy and correctness）, and finally, define the control tests of non degradation of the method performances. This paper outlines the steps for validating a biological method of analysis. It involves the construction of an experimental design, a statistical model, and the preparation of an interne laboratory reference material （pilot vaccine）. The latter is used to study the impact of deviation and variation factors, in order to, optimize the analytical method, to evaluate the bias （random error）, and to calculate the uncertainty of measurement, and make the control charts. This method is applied in the titration of live viral vaccines of Gumboro disease on chicken＇s embryos fibroblasts. The experimental results show that potential influence factors related to the titration method had no significant influence on the obtained results. Taking into account these results, an operating mode has been elaborated. The finalized method proved to be faithful to standard deviation of repeatability and reproducibility of 0.21 and 0.22, respectively, with a confidence level of 95%. The calculated uncertainty of measurement is equal to 0.2, which represents the average error level of a titer. A homogeneous stock of interne laboratory reference vaccine （MRIL）, with an average titer of 5.9 log DIT 50, was produced and the control chart set in away to provide the laboratory with an important tool of control and monitoring of the viral titers evolution in time, as well as, the mastery of the validated titration method performances.

考虑不确定性的数值模拟模型确认方法

飞行器在其研发、生产和使用的整个寿命周期中都存在大量不确定性,这会导致数值模拟输出也具有不可忽视的不确定性,因此开展基于数值模拟技术的飞行器设计前必须进行模型确认。目前围绕数值模拟已开展了大量不确定性量化(uncertainty quantification,UQ)的研究工作,但是如何基于UQ的结果科学地进行模型参数修正,形成系统的数值模拟模型确认的闭环流程,构建高可信的数值模拟预测模型,还较少有研究报道。为此,提出一种考虑不确定性的数值模拟模型确认方法,发展一种基于优质小样本的模型参数修正策略,建立一套融合不确定性量化、全局灵敏度分析、参数修正的模型确认闭环流程,为构建高保真的数值模拟提供科学系统的思路,并通过翼型的仿真算例验证了该方法的有效性。

航空锂电池模型不确定度量化方法

航空锂电池模型不确定度决定了以航空锂电池模型为基础的仿真分析结果的可信度。以钴酸锂体系航空锂电池二阶Thevenin等效电路模型为例,通过验证实验,采用基于拉丁超立方抽样技术的蒙特卡洛仿真以概率的形式量化该模型参数不确定度,采用改进型面积度量验证法量化模型形式不确定度,最后采用概率盒的方法将两种来源的不确定度转换到相同的计量单位下。指定置信水平90%,得到模型总不确定度,并根据量化结果指导模型进行改进。

船舶CFD模拟不确定度分析与评估新方法研究

比拟测量不确定度,视CFD模拟结果为随机变量,阐述了CFD模拟不确定度的定义、来源、分类和表示形式。基于正交试验设计和方差分析方法,提出了CFD不确定度分析中验证的内涵及实施流程;基于统计推断理论,提出了CFD不确定度评估中确认的标准及判断程序。应用Fluent软件及文中所建方法,针对阻力系数和伴流分数进行CFD模拟不确定度分析评估的实例计算,给出了对模拟结果有重要影响的计算因子和交互作用以及各类不确定度分量的大小,并指出就目前采用的CFD模拟技术而言,尽管其结果的分散性或不确定度数倍于物理试验,但其近似性或可信度已可接受。

爆轰模拟不确定度的量化方法

通过对数值模拟不确定度产生机制的理论分析以及对不确定度从考核区到应用区发展趋势的反演,展示数值模拟不确定度量化评估的关键技术.基于工程设计的现实需求和数值模拟中验证与确认的思想,提出数值模拟用于对爆轰系统进行科学预测时不确定度的评估框架,并结合实例对方法进行演示和验证.

基于方法验证数据用Top-down方法评估测量不确定度

依据现有指南和规范,在分析方法标准验证实验和报告中,常常分别评估准确度和精密度。这容易导致以加标回收率表示的准确度数据缺乏良好精密度支持的现象。基于ISO 11352原理,首次提出在不增加实验室分析人员工作量的情况下,利用自上而下技术评估方法测量不确定度,即同时考虑准确度与精密度作为一个综合性指标评估方法性能。这是标准制修订时落实测量不确定度条文一条操作性强的技术路线。利用改进后的加标回收率计算结果评估方法准确度。5组方法验证实测数据表明,用测量不确定度这一综合性指标评估方法性能比分别用准确度和精密度指标更符合实际情况。他可引导实验室分析人员在设计和处理方法验证数据时,更加重视方法精密度。在修订HJ 168—2010时,建议增加测量不确定度这一综合性指标评估方法性能。

简版无法忍受不确定性量表在中学生中应用的效度和信度

目的:检验简版无法忍受不确定性量表(IUS-12)测评中学生人群的适用性。方法:选取中学生800人(样本1)用于进行条目分析和探索性因子分析;另外选取中学生475人(样本2),用于进行验证性因子分析及聚合效度、区分效度、组合信度以及内部一致性信度检验。在样本1中,选取90人施测特质焦虑分量表(T-AT)、元担忧量表(MWQ)、特质抑郁分量表(T-DS)、无法忍受不确定性量表(IUS)检验效标效度;半个月后,在样本1中随机选取120人进行重测。结果:探索性因子分析得到预期性行为、抑制性行为与预期性情绪3个因子,累积解释量表总变异量的53.42%;验证性因子分析表明模型拟合较好(χ~2/df=2.57,CFI=0.91,TLI=0.88,RM SEA=0.05,SRM R=0.06);IUS-12中文版总分与T-AT、MWQ、T-DS、IUS得分均呈正相关(r=0.44、0.54、0.40、0.93,均P<0.001)。IUS-12中文版总量表的Cronbachα系数和组合信度分别为0.79和0.83,3个因子的α系数和组合信度分别为0.74和0.82、0.74和0.67、0.74和0.67;IUS-12中文版总量表的重测信度为0.80,3个因子的重测信度分别为0.82、0.67和0.66。结论:修订后的简版无法忍受不确定性量表测评中学生显示有良好的效度和信度。

APSIM-Sugar模型在云南半湿润半干旱蔗区的适应性研究

【目的】本研究对APSIM-Sugar模型在云南半湿润半干旱蔗区的适应性进行评价。【方法】从研究地区2个代表站点甘蔗大田试验获取调参验证数据集,基于标准品种Q117模型参数,采用试错法对8个关键品种参数进行优化和模拟精度评价。【结果】确定了Q208和ROC22两个甘蔗新品种的模型参数优化值,评估了模型在云南蔗区的产量糖分模拟误差范围。结果显示蔗糖产量实测值与模型模拟值显著相关,绝对误差小于2 t/hm^2,斜率在0. 8～1. 26,R^2大于0. 8。【结论】经过校验的APSIM-Sugar模型能较好模拟云南半湿润半干旱蔗区甘蔗的生长发育过程,并响应环境变化造成的产量和糖分差异,但是在多年宿根和极端环境条件下的模拟精度仍有待提高。模型品种参数和输入数据的不确定性是造成模型模拟结果不确定性的重要原因。

圈闭资源量参数概率分布及有效性检验

概率统计法是目前圈闭资源量计算的最有效方法,其计算结果的大小、精度与合理性受各资源量参数的概率分布所决定。因此,如何构建适合不同地区、不同领域圈闭的资源量参数概率分布,并通过合理的有效性检验以证明其可靠性,是概率统计法应用的关键。基于勘探风险分析思想,建立了圈闭资源量参数概率分布构建及检验流程,并给出了相应的资源量参数不确定性分析方法。其中,有针对性地提出将数学假设检验方法应用于圈闭资源量参数模型的有效性检验之中,并根据资源量参数的地学和数学特征,建立了相应数学假设检验流程。最后,以我国东部某预探圈闭为实例,阐述了上述流程和方法的应用过程。实例结果表明,利用上述方法可以有效地实现资源量参数概率分布的定量化分析,其资源量计算结果与该圈闭钻后预测储量规模基本吻合,验证了上述方法的可靠性与合理性。