Using the concept of a measurement system to characterize measurement models used in psychometrics

The philosophy of measurement in the social and behavioral sciences is seen (from without) as typically following the representational viewpoint. However, in practice, this is not the case for the great majority of measures that are developed in this area. The paper surveys several approaches to measurement in the social sciences (i.e., Classical Test Theory, Guttman Scaling, Item Response Theory, Rasch Scaling, and Construct Modeling), as examples of measurement approaches in the area of psychometrics, and uses the foundational concept of a measuring system, as developed by Mari [1], to explicate the logic on which these approaches are based and thus enable a comparison with measurement approaches used by other fields such as engineering and physics. The paper uses the underlying concept of the standard reference set (one of the essential features of Mari’s formalization) to show how the five approaches differ, and also how they are related. The importance of these differences, and the consequences for measurement using those approaches are also explicated and discussed.     

An introduction to the Rasch measurement approach for metrologists

In the interests of fostering an inter-disciplinary dialogue, increasing collaboration between “hard” and “soft” measurement scientists, and learning from one another, the paper develops an analytical discussion of common elements between metrology and psychometrics. A simple example of physical measurement is introduced according to the conceptualization and terminology of the International Vocabulary of Metrology (VIM), and then its structural analogy to a test using Guttman items is shown. On this ground the example is generalized so to include a probabilistic component, and this leads to the basic Rasch model. Some notes on the delicate issue of measurement validity conclude the paper, whose aim, in the long run, is a measurement-related shared concept system, and a terminology understandable in both physical and social sciences.     

On the philosophical foundations of psychological measurement

Measurement has played a central role in the development of the physical sciences and engineering, and is considered by many to be a privileged method for acquiring information about the world. It is thus unsurprising that the psychological sciences have also attempted to develop methods for measurement. However, it is not clear how the ways in which psychological scientists understand measurement accord with how the concept is understood in other scientific disciplines, or by the professional and general publics. In part this may be due to the ways in which several distinct strands of thinking about scientific inquiry (and measurement in particular) have influenced the work of psychological scientists over roughly the past hundred years. Given that such influences are often not studied or even acknowledged, many psychological scientists may be unaware of the resulting tensions in their conceptual vocabulary, and of the gaps between the nature of their claims on psychological measurement and the substantiation for those claims. The aim of this paper is to overview the major philosophical influences on thinking about psychological measurement, and to note the pitfalls of some of the extreme positions that have emerged. We hope that such an overview may help facilitate greater clarity concerning the semantics of measurement claims made by psychological scientists.     

Mathematical modelling in the analysis and design of hard and soft measurement systems

This paper briefly looks into the role and extent of mathematical modelling in the design and analysis of measurement systems, especially measurement sub-systems in the form of instruments and instrument elements. These fall within the classical domain of hard measurement (physical, strongly-defined measurement). It also examines the role and use of mathematical modelling in the area of soft measurement (non-physical, weakly defined measurement). These constitute two sub-sets of widely-defined measurement. Based on a number of examples it demonstrates the use of modern modelling techniques in the design and analysis of sub-systems in measurement technology. In doing so, it focuses on the scope and importance of physical modelling at a sub-system level, which ultimately contributes to modelling activities at a global systems level.     

灰色关联分析方法在双目视觉测量系统误差分析中的应用

针对双目视觉测量系统存在误差因素繁多、分析困难等问题,提出了一种基于灰色关联技术的误差分析方法。考虑视觉系统的灰色属性,将灰色系统理论及其相关技术运用于视觉测量系统的误差分析。以镜头畸变、质心定位误差及双目视觉系统内、外参数等9项因素或参数为自变量,通过基于单项因素变化的实验,获取了误差分析的数据样本;采用灰色数据处理方法及灰色关联分析技术,从无明显规律的数据样本中明确了视觉系统各项误差因素对最终测量精度的影响。分析结果证明了灰色理论用于定量分析视觉系统误差的正确性和有效性;在灰色理论意义下,镜头径向畸变、切向畸变、摄像机夹角及特征点质心定位误差4项因素对测量精度的关联度均大于等于0.859,高于其余误差因素。     

应用AutoLisp语言和属性块实现AutoCAD中机械零件的表面粗糙度标注

运用AutoLisp语言,结合AutoCAD中具有属性的块,实现机械零件表面粗糙度的菜单和工具条式标注,解决了AutoCAD中无粗糙度标注的问题,提高了绘图效率。     

超精密测量是支撑光刻机技术发展的基石

光刻机是尖端装备的珠穆朗玛峰。超精密测量是支撑光刻机产品研发与制造,保证光刻机产品制造精度等级与质量水平的基石。本文综述了光刻机产业的特点与发展趋势。在此基础上,从零部件、分系统、整机集成、整机性能层面阐述了超精密测量对光刻机技术发展的支撑作用。分析了光刻机产品精密能力提升的途径和超精密光刻机产业测量体系建立的必要性,包括管控超精密光刻机产品制造质量的工业测量体系和管控光刻机产品工业测量体系量值准确可靠的计量体系。提出了建设光刻机产业计量测试中心的必要性。     

可重构软件及其在测控仪中的应用

对测控仪软件进行可重构开发 ,满足了测控仪硬件的可重构要求。可以方便地增加新的功能 ,减少重构的斜升时间 ,迅速响应用户的要求。针对可重构机电测控实验平台的要求 ,开发出配套的可重构软件 ,扩展了测控平台的功能 ,实验由 5个增加至 12个以上     

用于无人机飞行控制系统的分布式测控系统设计

将复杂庞大的工程项目分解成多个功能单一的小模块实现，是COM组件设计思想的具体体现。在简要介绍分布式对象与对象服务后，本文设计了具有命名服务和事件服务两种对象服务功能的事件提供者和事件消费者COM组件以及其他诸如硬件驱动、图形显示等COM功能组件。这些组件提供的远程对象状态监控以及基于事件的对象间数据通信功能，使应用于无人机飞行控制系统的分布式测控系统的实现成为可能。最后，本文通过分布式传感器监测系统开发实例，说明本文所提出的组件设计方法能帮助系统设计者方便地扩展系统，加快系统开发速度，提高设计效率。     

面向航天制造企业的 LIMS 系统设计研究

探讨了航天制造企业理化管理的特点和普遍存在的问题,以及建设实验室信息管理系统（LIMS）的必要性;分析并构建面向航天制造企业的实验室管理系统的业务流程和功能架构;基于Dynamics AX平台建设实验室管理系统,实现企业对理化检测的科学、规范、高效管理。     

胶囊机器人磁驱动力建模与测量

可吞式无线磁驱胶囊机器人在胃肠道内的诊疗效果与机器人受到的外部磁驱动力密切相关。本文建立了外部磁驱动力的理论模型,基于等效磁荷模型推导了两径向充磁环形永磁体相互作用的数学表达式,采用自适应递归式计算方法开展了数值计算。此外,发展了环形永磁体间磁力实时测量方法,并开发了磁力-间距同步测量仪器开展实验研究,且建立了3D环形永磁体有限元仿真模型。实验测量磁力-间距关系曲线与理论计算和有限元仿真结果吻合较好,误差小于4%,验证了理论模型和有限元仿真模型的准确性和可靠性。通过参数分析,揭示了胶囊机器人内置永磁体长度、厚度和体积对磁力的影响规律。研究结果为精准驱动胶囊机器人在胃肠道内运动奠定了理论基础。     

编解码电路在温度测控系统中的应用

本文介绍一种用编码、解码集成电路进行多点温度测控的系统。文章首先介绍编解码电路ＳＹ８０８Ｅ／Ｄ,然后给出温度测控系统的硬件电路及软件框图。     

如何减少酸雨pH计的测量误差浅析

根据铜仁国家酸雨观测站的实践经验,详细介绍了上海雷磁牌PHS-3B型酸雨pH计的工作原理、操作方法、日常维护以及常见故障排除要点。熟悉和了解设备的工作和设计原理,有助于观测员正确使用和维护仪器,帮助准确诊断分析测量误差和掌握排除故障技能,以利于提高酸雨观测水平和业务质量。     

编解码电路在遥测遥控系统中的应用

本文介绍了一种新颖的编解码芯片的工作原理,给出了一个应用实例,讨论了ＵＭ３７５８－１０８在浑水浊度测控系统中的应用,最后给出了实验结果。     

基于单片机的监测数据无线传输装置设计与实现

监测数据的无线传输在无线遥控、遥测、复杂环境的工业数据采集等领域具有广泛的应用,监测点利用单片机采集数据,通过无线数据传输模块传输,在监测站利用无线数据传输模块接收后,发送到监测站计算机,实现远程监测的目的。     

飞机舱盖试验自动测控系统的设计

文章介绍了飞机舱盖试验自动测控系统原理，硬件组成和软件方案。讨论了系统的安全性与可靠性设计。试验的调试和运行表明，系统综合指标满足设计要求。     

Application of contour mapping techniques to the measurement of high precision spheres

Some recent advances in the mapping of the surface features of 40 mm diameter quartz rotors spherical to a precision of about 30 nm are reported. Multiple great-circle roundness measurements have been taken over the sphere using a modified Talynova system and these have generated data suitable for use with standard geophysical contour mapping programs. Examples are given of the type of surface feature visualization now available down to a resolution of about 3 nm.     

An overview of the measurement of electrical quantities from 1979 to 2002

In the last few years measurements of electrical quantities have shown a noticeable trend especially toward a more and more wide range of frequencies. To understand this trend may be useful to know the history of a Technical Committee on “Measurement of Electrical Quantities”, the IMEKO TC4, history which is also a significant part of my life. I hope the reader will learn not only of the sequence of dates, but also of the humanity and commitment of the founding members, of the joys and difficulties that arise within a Technical Committee, and finally of the friendship among people from the entire world. The paper provides a survey of the TC4 life from 1979 to 2002, reporting on the Symposia, the Workshops and the round tables organized in that period. The most important events are mentioned with special reference to the historical context relevant to the measurement of electrical quantities. That period was crucial for the TC4 activities in the following years.     

Evaluating the measurement capability of a wheel profile measurement system by using GR&R

Reliable data with less variation play a key role for acceptance of the usefulness of the measurement output of a wheel profile measurement system (WPMS) in a railway network. However, in practice, most studies are carried out without checking the reliability of data from such a system, which may lead to inappropriate maintenance strategies. To ensure the measurement capability of WPMS and to support robust maintenance in railway systems, this study has evaluated measurement data for the flange height, flange thickness, flange slope, and tread hollowing of rolling stock wheels by using gauge repeatability and reproducibility (GR&R). In this study, acceptance and rejection criteria for the precision-to-tolerance ratio (PTR), signal-to-noise ratio (SNR), and discrimination ratio (DR) have been employed to evaluate the measurement capabilities. For the purpose of illustration, we have implemented a new proposed approach. This approach involves both an analysis using graphs with four regions with a confidence interval (CI) of 95% and an analysis using a graph with three regions with only the predicted values; the latter type of graph represents an innovation made in this study. This graph has the advantages that it can visualize three different levels of data quality in same figure, namely “unacceptable”, “acceptable” and “good”, and also include a number of measures without becoming unclear, which are features that have been missing in previous presentations. The results show that the measurements of the flange slope are on an acceptable level, while those for the flange height, flange thickness and tread hollowing have to be rejected as unacceptable. The action proposed for increasing the quality of data on the flange height, flange thickness and tread hollowing is to enhance the calibration of the WPMS. In conclusion, GR&R is a useful tool to evaluate the measurement capability of WPMS and to provide helpful support for maintenance decision making. This investigation also shows that there is good reason to be careful when selecting measures and when interpreting the results, since, for a certain wheel profile parameter, when one measure is used, the results may be acceptable, but when another measure is used, the results may be unacceptable.     

大型中阶梯光栅衍射效率测试仪器设计与集成

光栅衍射效率反映光栅的设计与刻划质量,对于使用者和制造者均至关重要。针对国内首台500 mm×400 mm中阶梯衍射光栅刻划机的研制,有必要构建相应的衍射效率测试系统,以定量评价光栅的制作水平,为光栅设计与制造工艺的改进提供必要的测试手段。基于串联色散相减原理,改进了常规C-T结构的测量单色仪光路,并对前置单色仪、测量单色仪光路进行联合优化,设计了待测光栅多维调整台、探测器组件等。提出了N.A.为0.1的三光栅扫描前置单色仪的标定方法,以及测试仪器的系统误差修正方法。前置单色仪标定结果表明,其在190~1 100 nm光谱范围内的波长输出精度为±2 nm,程控狭缝开启精度为0.002 mm。修正后的衍射效率测量精度为2%,重复精度为0.5%。初步的测量结果显示,测试设备可以满足500 mm×400 mm中阶梯光栅衍射效率定量检测需求,在工作谱段内实现衍射效率-波长连续曲线的自动测量。