Adaptive Monte Carlo and GUM methods for the evaluation of measurement uncertainty of cylindricity error

Measurement uncertainty is one of the most important concepts in geometrical product specification (GPS). The “Guide to the expression of uncertainty in measurement (GUM)” is the internationally accepted master document for the evaluation of uncertainty. The GUM method (GUMM) requires the use of a first-order Taylor series expansion for propagating uncertainties. However, when the mathematical model of measurand is strongly non-linear the use of this linear approximation may be inadequate. Supplement 1 to GUM (GUM S1) has recently been proposed based on the basis of probability density functions (PDFs) using the Monte Carlo method (MCM). In order to solve the problem that the number of Monte Carlo trials needs to be selected priori, adaptive Monte Carlo method (AMCM) described in GUM S1 is recommended to control over the quality of the numerical results provided by MCM.The measurement and evaluation of cylindricity errors are essential to ensure proper assembly and good performance. In this paper, the mathematical model of cylindricity error based on the minimum zone condition is established and a quasi particle swarm optimization algorithm (QPSO) is proposed for searching the cylindricity error. Because the model is non-linear, it is necessary to verify whether GUMM is valid for the evaluation of measurement uncertainty of cylindricity error. Then, AMCM and GUMM are developed to estimate the uncertainty. The procedure of AMCM scheme and the validation of GUMM using AMCM are given in detail. Practical example is illustrated and the result shows that GUMM is not completely valid for high-precision evaluation of the measurement uncertainty of cylindricity error if only the first-order terms in the Taylor series approximation are taken into account. Compared with conventional methods, not only the proposed QPSO method can search the minimum zone cylindricity error precisely and rapidly, but also the Monte Carlo simulation is adaptive and AMCM can provide control variables (i.e. expected value, standard uncertainty and lower and higher coverage interval endpoints) with an expected numerical tolerance. The methods can be extended to the evaluation of measurement uncertainty of other form errors such as roundness and sphericity errors.     

考虑不确定性因素下的裂纹张开位移趋势的预测方法

把温度影响下的COD实验数据，用灰色理论中的累加方法，进行二次累加可以使一组没有规律的数据，成为一条光滑的曲线。然后利用回归理论中的多项式模拟曲线进行低温试验数据的预测。再根据模糊和随机理论给出一个实验数据区间系数，用于确定预测试验数据的估计区间。算例的结果表明其预测结果的有效性。     

On the validity of acidity function extrapolation to zero added ionic strength and its impact on the uncertainty of primary pH measurements using the Harned cell

The determination of pH is the most commonly made analytical measurement throughout the world and the vast majority of these measurements are made to fulfil quality assurance and control requirements where traceability is required. Therefore, primary measurements of pH are essential to establish traceability to the agreed definition of this important quantity and disseminate this traceability to end users. The extrapolation of the acidity function to zero added ionic strength is an essential step in the Harned cell methodology for primary pH measurement. This approach relies on a number of solution chemistry approximations. Potential limitations of the current extrapolation method including possible non-linearity, and the validity of some approximations derived from solution chemistry, are reviewed and explored. Implications for the uncertainty of pH measurements using the Harned cell are discussed.     

Bayesian approach for measuring EEPROM process capability based on the one-sided indices CPU and CPL

The purpose of process capability analysis is to provide numerical measures on whether a process is capable of reproducing items meeting the manufacturing specifications. Capability analyses have received considerable recent research attention and increased usage in process assessments and purchasing decisions. Most existing research works on capability analysis focus on estimating and testing process capability based on the traditional distribution frequency approach. In this paper, we propose a Bayesian approach based on the indices C_PU and C_PL to measure EEPROM process capability, in which the specifications are one-sided rather than two-sided. We obtain the credible intervals of C_PU and C_PL and develop a Bayesian procedure for capability testing. The posterior probability p, for which the process under investigation is capable, is derived. The credible interval is a Bayesian analog of the classical lower confidence interval. A process satisfies the manufacturing capability requirements if all the points in the credible interval are greater than the pre-specified capability level w. To make this Bayesian procedure practical for in-plant applications, a real example of an EEPROM manufacturing process is investigated, demonstrating how the Bayesian procedure can be applied to actual data collected in the factories.     

A hybrid approach to selective-disassembly sequence planning for de-manufacturing and its implementation on the Internet

De-manufacturing (DM) is a process to separate a product into components and materials that will be maintained, replaced, reused, or recycled. Disassembling a selected set of parts in a product, defined as selective-disassembly, is an essential need in product DM. Although it is necessary to have an efficient and optimized sequence planning for selective-disassembly to reduce DM-related cost, it is more important to consider de-manufacturability for product life cycle cost at the early stage of a product development. However, the product analysis related to DM is generally regarded as a post-process in product development. Current product development environments require all industry in a supply chain to concurrently develop their specialized components corresponding to the end item requirement within a short time frame. Therefore, it is an emerging issue to add global concurrent de-manufacturability analysis into product development environments. An efficient sequence planning approach and a supporting tool are highly demanded. This paper presents a hybrid approach to selective-disassembly sequence planning for DM, which is based on both topological disassemblability and tool accessibility. In addition, a Web-based application on a three-tier Internet environment is implemented for the global concurrent de-manufacturability analysis.     

An improvement EMD method based on the optimized rational Hermite interpolation approach and its application to gear fault diagnosis

A demodulation technique based on improvement empirical mode decomposition (EMD) is investigated in this paper. Firstly, the problem of the envelope line in EMD is introduced and the drawbacks of two classic interpolation methods, cubic spline interpolation method and cubic Hermite interpolation method are discussed; then a new envelope interpolation method called optimized rational Hermite interpolation method (O-EMD) is proposed, which has a shape controlling parameter compared with the cubic Hermite interpolation algorithm. At the same time, in order to improve the envelope approximation accuracy of local mean, the parameter determining criterion is put forward and an optimization with Genetic Algorithm (GA) is applied to automatic select the suitable shape controlling parameter in each sifting process. The effectiveness of O-EMD method is validated by the numerical simulations and an application to gear fault diagnosis. Results demonstrate that O-EMD method can improve the reliability and accuracy significantly compared with traditional EMD method.     

估计威布尔分布参数,可靠寿命和可靠度的置信限的新方法

本文通过构造两个统计量和中心极限定理的应用，提出了一种估计双参数威布尔分布的形状参数和尺度参数，可靠寿命以及可靠度的置信限的新方法，相对现成的方法，该法大大简化了估算过程且精度更好，文中给出了用该法估计实例。     

A structured approach to the automatic planning of machining operations for rotational parts based on computer integration of standard design and process data

The traditional procedure for developing a manufacturing process plan involves a number of interconnected steps beginning with the initial design and culminating in the instructions for the machine that makes the part. When performed manually, the procedure is very tedious, time consuming, and often, inconsistent. This paper presents an alternative method, called the Automated Machining-Operations Process-Planning System (AMOPPS), to automatically generate the process plan and the numerical control (NC) instructions to machine a part that has been previously designed by a computer-aided design (CAD) system. AMOPPS combines preset planning logic and data from three databases (viz., workpiece material, machine tool, and cutting tool) with appropriate data from a CAD database and information from the user about the workpiece to calculate the optimal machining parameters, print a process plan, print the corresponding NC program listing, and provide an on-screen animation of the cutting passes. Although AMOPPS is a prototype, it can be extended by adding other modules, and it does provide a structure through which a fully integrated manufacturing system can be developed.     

A histological and immunohistochemical study on the parabronchial epithelium of the domestic fowl's (Gallus gallus domesticus) lung with special reference to its scanning and transmission electron microscopic characteristics

The current study was designed to give complete histo-and immunohistochemical features of the parabronchial epithelium of domestic fowl's (Gallus gallus domesticus) lung with special reference to Scanning electron microscope (SEM) and mean transmission electron microscope (TEM) features. The lung exhibited variable-sized atrial openings encircled by exchange tissue zones. The parabronchial atrial chambers appeared as ovoid and polygonal-shaped that separated by the well-developed interatrial septum. The deep atrial lumens had blood vessels pierced by openings that represent the infundibula. The parabronchial blood capillaries meshwork was branched and exhibited ovoid-shaped air capillaries with numerous extravasated blood vessels. By TEM, there were several air capillaries and groups of squamous and endothelial respiratory cells and the squamous cells had oval nucleus with evenly distributed chromatin. The endothelial respiratory cells had few microvilli on their free surfaces. The parabronchial tubes opened into a group of widened atria that had smooth muscle bundles at the interatrial septa. The atrial chambers led to narrow infundibula. Moreover, the lining epithelium of parabronchi, atria, infundibula, and air capillaries was formed by simple squamous epithelium. Air capillary walls were lined by two types of respiratory cells (Types-I and II). Collagen fibers were concentrated within the tunica externa layers of the parabronchial blood vessels as well as, they were observed in CT interparabronchial septa. Immunohistochemically, the elastin immunoreactivity was detected around the parabronchial blood vessels, at the base of each parabronchial atria, and in the area encircling the alveolar-capillary walls. Our work concluded that there are a relation between the fowl's lifestyle and the surrounding environmental conditions.