Optimal confidence intervals on the variation for operators and gauge in manufacturing process with repeated measurements

It is necessary to measure the attributes of the parts in any manufacturing process. It is also important to monitor measurement system in the manufacturing process because repeated measurements of the attributes include variability as well as target value. This paper considers variabilities due to repeated measurements, operators, and gauge in a measurement system. The measurement system is statistically modeled as a two-factor mixed model with one covariate and interaction. That is, this model employs J operators randomly chosen to conduct measurements on I randomly selected parts from a manufacturing process. In this experiment each operator measures each part K times. This paper aims to provide engineering practitioners with statistically optimal confidence intervals on the variation due to operators and gauge resulted from a measurement system statistically modeled. The optimal confidence intervals are based on a moderate large sample method (MLS) and a generalized p-value method (GEN). The confidence intervals proposed can be useful tools to determine whether a manufacturing process is adequate for monitoring a measurement system.     

Monitoring Bench and Procedure for Measurement of the Parameters of Multiport Fiber-Optic Couplers

A monitoring bench and procedure for measurement of the transmission matrix of (N × N)-type multiport fiber-optic couplers using mechano-optical scanning of the bench to achieve a high measurement rate are presented. It is shown that it is possible to measure the elements of the transmission matrix with error at most ±0.2 dB.     

Joint Monitoring of Process Location and Dispersion Based on CUSUM Procedure and Generalized Likelihood Ratio in the Presence of Measurement Errors

In this paper, we propose a new methodology based on the combination of cumulative sum procedure and generalized likelihood ratio statistic for joint monitoring of the process location and dispersion. Then, we explore the effect of measurement errors on detecting ability of the proposed control chart when (i) the variance of measurement error is constant (ii) the variance of measurement error increases linearly as the level of the process mean increases. We also utilize multiple measurements on each sample point in order to decrease the adverse effects of measurement errors on the performance of the proposed control charts. Two numerical examples based on simulation studies are given to evaluate the ability of the proposed methods in terms of average run length, median run length, standard deviation of run length, and the first and third quantile points of the run length distribution (Q₁ and Q₃). Finally, a real life example is given to illustrate the application of the proposed method. Copyright © 2017 John Wiley & Sons, Ltd.     

Modeling and Measuring All the Elements of an Ultrasonic Nondestructive Evaluation System I: Modeling Foundations

Abstract

A comprehensive model of an ultrasonic nondestructive evaluation (NDE) flaw measurement system is developed that combines models for the electrical components (pulser/receiver, cabling), electromechanical components [transducer(s)], and the acoustic/elastic processes present in the materials being inspected, including the scattering of ultrasonic waves from a flaw. This model is called the electroacoustic measurement (EAM) model. Here, in Part I, the underlying modeling foundations of the EAM model are described in detail and the use of the EAM model is demonstrated in a transducer design study. This EAM model provides a new, powerful tool for analyzing virtually any element in the measurement process. In Part II it will be shown that this power can be extended to characterizing typical commercial measurement systems through the use of models and purely electrical measurements of the system components.     

气相色谱内标法测定塑料制品中乙苯和苯乙烯含量的不确定度评定

目的 对气相色谱内标法测定塑料制品中乙苯和苯乙烯含量进行不确定度评定，为塑料制品中乙苯、苯乙烯含量测定的准确性提供参考。方法 依据GB 31604.16—2016采用气相色谱内标法对塑料制品中乙苯和苯乙烯含量进行测定，根据相应的测量模型，分析不确定度主要影响因素的来源，并对各影响因素引入的相对标准不确定度进行评估。结果 测量塑料制品中乙苯、苯乙烯的扩展不确定度分别为(23.83±1.50)、(23.90±1.26)mg/kg(P=95%、k=2)。结论 结果表明，混标工作液配制、试样重复测量、气相色谱仪性能是影响乙苯和苯乙烯含量测量不确定度的主要因素，应选择精度高且量程合适的量具，加强气相色谱仪的期间核查，提高实验人员操作的熟练水平，进一步减小测量不确定度，使测量结果更为准确、可靠。     

Upper critical field of Nb and Nb+1 at % Ta determined by calorimetric and magnetic methods

The upper critical fieldH _c2 of single-crystal Nb and arc-melted Nb+1 at % Ta near the critical temperatureT _c has been measured using both calorimetric and magnetic methods. In contrast with theH _c2 curve determined by the magnetic measurement, which shows a clear upward curvature, the calorimetric measurement gives a nearly straight line nearT _c. The data disagree with available models. A possible explanation is given.     

Electrical characterization and reliability evaluation of capacitors by means of in situ leakage current measurements

The in situ leakage current measurement technique is presented for the high-resolution observation of the electrical behaviour of dielectric material systems, e.g. capacitors, at high temperatures. This technique is useful for the electrical characterization of dielectrics during linear heating experiments and/or isothermal steps. Applied to a population of test structures, the in situ leakage current measurement technique is a rapid and powerful tool to assess the reliability and quality of dielectric components and assemblies. Results obtained on populations of film capacitors and ceramic capacitors are presented. © 1998 John Wiley & Sons, Ltd.     

When is R2 appropriate for comparing customer and supplier measurement systems?

Linear regression analysis is often used to compare paired supplier and customer measurements of a given quantitative product characteristic in a shipment of products. Specifically, the coefficient of determination, R², is then used to determine if the supplier's and the buyer's measurement systems are in conformity, with sufficiently high values implying agreement. In this article, we show that R² istextitnever an appropriate statistic for making this determination. Examples are provided and an appropriate methodology for comparing two measurement systems is delineated. Copyright © 2011 John Wiley & Sons, Ltd.     

Modeling and Measuring All the Elements of an Ultrasonic Nondestructive Evaluation System I: Modeling Foundations

A comprehensive model of an ultrasonic nondestructive evaluation (NDE) flaw measurement system is developed that combines models for the electrical components (pulser/receiver, cabling), electromechanical components [transducer(s)], and the acoustic/elastic processes present in the materials being inspected, including the scattering of ultrasonic waves from a flaw. This model is called the electroacoustic measurement (EAM) model . Here, in Part I, the underlying modeling foundations of the EAM model are described in detail and the use of the EAM model is demonstrated in a transducer design study. This EAM model provides a new, powerful tool for analyzing virtually any element in the measurement process. In Part II it will be shown that this power can be extended to characterizing typical commercial measurement systems through the use of models and purely electrical measurements of the system components.     

Corrections for Thermal Expansion in Thermal Conductivity Measurement of Insulations Using the High-Temperature Guarded Hot-Plate Method

The anticipation of recently published European product standards for industrial thermal insulation has driven improvements in high-temperature thermal conductivity measurements in an attempt to obtain overall measurement uncertainties better than 5 % (k = 2). The two measurement issues that are focused on in this article are the effect of thermal expansion on in situ thickness measurement and on determining the metering area at high temperatures. When implementing in situ thickness measurements, it is vital to correct the thermal expansion of components in a high-temperature guarded hot plate (HTGHP). For example, in the NPL HTGHP this could cause 3.2 % measurement error for a 50 mm thick specimen at 800 °C. The thermal expansion data for nickel 201 measured by NPL are presented, and the effect of this on the metering area of NPL’s heater plate (nickel 201) is discussed.     

Modeling and Measuring All the Elements of an Ultrasonic Nondestructive Evaluation System I: Modeling Foundations

A comprehensive model of an ultrasonic nondestructive evaluation (NDE) flaw measurement system is developed that combines models for the electrical components (pulser/receiver, cabling), electromechanical components [transducer(s)], and the acoustic/elastic processes present in the materials being inspected, including the scattering of ultrasonic waves from a flaw. This model is called the electroacoustic measurement (EAM) model . Here, in Part I, the underlying modeling foundations of the EAM model are described in detail and the use of the EAM model is demonstrated in a transducer design study. This EAM model provides a new, powerful tool for analyzing virtually any element in the measurement process. In Part II it will be shown that this power can be extended to characterizing typical commercial measurement systems through the use of models and purely electrical measurements of the system components.     

The measurement of a country's scientific and technological potential

The paper suggests a formula for the measurement of the national science and technology potential. This is based on a decision-making framework for the development of indicators for theS & T system.     

Call for Papers

Abstract

In a previous paper it was shown that the distribution of measured values for a retrodictively optimal simultaneous measurement of position and momentum is always given by the initial state Husimi function. This result is now generalized to retrodictively optimal simultaneous measurements of an arbitrary pair of rotated quadratures ? _{θ 1} and [pcirc] _{θ 2}. It is shown, that given any such measurement, it is possible to find another such measurement, informationally equivalent to the first, for which the axes defined by the two quadratures are perpendicular. It is further shown that the distribution of measured values for such a measurement belongs to the class of generalized Husimi functions most recently discussed by Wünsche and Büzek. The class consists of the subset of Wódkiewicz's operational probability distributions for which the filter reference state is a squeezed vacuum state.     

Design of structures of adaptive measuring transformers of dynamic characteristics and parameters of objects

A methodology for designing the structure of a generalized adjusting measurement object as an element of a dynamic system of a measuring transformer which provides for parametric invariance of the latter by adaptive tuning of the compensating channel is proposed. Structures of adaptive measuring transformers of parameters and dynamic characteristics of measurement objects under their kinematic and power loading are obtained.Translated from Izmeritel'naya Tekhnika, No. 9, pp. 19–23, September, 1994.     

Forty years of underwater acoustical measurements at VNIIFTRI (all-Russian Institute of physicotechmcal and radio engineering measurements)

A brief survey covers research in underwater acoustical measurements at VNIIFTRI during the forty years since the Institute was founded. This research, aimed at establishing uniformity and correctness in underwater acoustical measurements, is linked to the creation of a standards base, to metrological studies bearing on full-scale, in situmeasurements, to the development and production of primary detectors (sensors) and measurement systems, and to the development of new measurement techniques. Prospects for the future of this work at VNIIFTRI are discussed.Translated from Izmeritel'naya Tekhnika, No. 11, pp. 43–48, November, 1995.     

Performance of the MEWMA-CoDa control chart in the presence of measurement errors

This paper can be considered as an extension of the work of Tran et al (for monitoring compositional data using a multivariate exponentially weighted moving average MEWMA-compositional data [CoDa] chart) by taking into account potential measurement errors that are known to highly affect production processes. A linearly covariate error model with a constant error variance is used to study the impact of measurement errors on the MEWMA-CoDa control chart. In particular, the influence of the device parameters (σ_M,b), the number of independent observations m, and the the number of variables p are investigated in terms of the MEWMA optimal couples (r,H) as well as in terms of their corresponding ARLs. A comparison between the Hotelling-CoDa T² and the proposed chart is made in order to show that the MEWMA-CoDa chart is more efficient in detecting shifts in the presence of measurement errors. A real-life example of muesli production, using multiple measurements for each composition, is used to estimate the parameters and also to demonstrate how the MEWMA-CoDa can handle measurement errors to detect shifts in the process.     

One‐sided Process Capability Assessment in the Presence of Measurement Errors

In the manufacturing industry, many product characteristics are of one‐sided specifications. The well‐known process capability indices C_PU and C_PL are often used to measure process performance. Most capability research works have assumed no measurement errors. Unfortunately, such an assumption is not realistic even if the measurement is conducted using highly sophisticated advanced measuring instruments. Therefore, conclusions drawn regarding process capability are not reliable. In this paper, we consider the estimation and testing of C_PU and C_PL with the presence of measurement errors, to obtain adjusted lower confidence bounds and critical values for true process capability, which can be used to determine whether the factory processes meet the capability requirement when the measurement errors are unavoidable. Copyright © 2005 John Wiley & Sons, Ltd.     

A new variant of the <Emphasis Type="Italic">P</Emphasis>-odd asymmetry measurement in extracted beams of nuclear reactors

We present the results of test runs on a new system intended for the P-odd asymmetry measurement using the integral method of detecting events for the neutron polarization switching frequency (f) above the fundamental frequencies of the fluctuation power spectrum of a reactor. The dependence of the error of the P-odd asymmetry measurement in the γ quantum yield of the ¹⁰B(n, α)⁷Li* ⟹ γ ⟹ ⁷Li(g.s.) reaction on f has been studied. It is established for the first time that an increase in f leads to a sharp decrease in the error of asymmetry measurement for a single detector and, beginning with f ∼ 15 Hz, this error ceases to depend on the reactor power fluctuations.     

Heterodyne vibration measurement

Analytic expressions are derived for the vibration amplitude and frequency in a heterodyne measurement method. The measurement accuracy is estimated.Translated from Izmeritel'naya Tekhnika, No. 8, pp. 39–40, August, 1993.     

Accurate Thermal Conductance and Impedance Measurements of Transition Edge Sensors

Past measurements of the thermal coupling of superconducting transition edge sensor (TES) calorimeters suspended on SiN membranes produced wide-ranging values for the exponent of the thermal coupling through the membranes. We present a measurement technique that is less susceptible to current dependence of the phase transition than the previous measurements. An initial measurement produced the expected exponent for a 2-D phonon gas: thermal conductance is proportional to T ². In doing these measurements, we employ a modification to Lindeman’s equivalent circuit technique for measuring TES complex impedance.