Correlated wear measurements using gold implantation, backscattering, nuclear activation analysis and profilometry

High and ultra-mild wear of Al-Si alloys under lubrication is measured (a) by comparison of initial and retained gold concentration in surfaces, (b) by tracking gold in the effluent lubricant or (c) alloy specific elements, and (d) by stylus profilometry. Wear >1 μm is best captured by method (d). However, (d) fails when both tribologically induced films have formed and wear is below 100 nm. Method (c) is efficient in a broad range of wear if element concentrations can be determined precisely. Methods (a) and (b) satisfy this requirement but they are only efficient for ultra-mild wear.     

An artificial immune algorithm for ergonomic product classification using anthropometric measurements

Product classification using anthropometric measurements leads to ergonomic product design and user satisfaction. We propose an effective artificial immune algorithm (AIA) to classify ergonomic products with multi-criteria anthropometric measurements and tune the AIA parameters with a full factorial experimental design approach. We demonstrate the applicability and efficacy of the proposed algorithm by considering the anthropometric measurements of the hand, developing an ergonomic computer mouse, and classifying consumers into three categories. The resulting classifications are compared with expert opinions to facilitate the conformity of the computer mouse to user requirements.     

High resolution microanalysis in materials science using electron energy loss measurements

The physical basis of microanalysis using measurements of electron energy losses associated with atom ionization or plasmon excitation in thin electron microscope specimens is explained in a simple manner. In addition the equipment used to resolve both the high and low energy regions of the loss electron spectrum is described. It is shown that ionization loss analysis is still in its infancy, but plasmon loss analysis has now been providing quantitative microanalytical data on light metal alloys for 8 years. The results obtained from both techniques and their application to specific metallurgical problems are reviewed. Conclusions are drawn concerning the future use of these techniques in high resolution microanalysis.     

Flow rate measurements in turbulent pipe flows with minimal loss of pressure using a defect-law

In the paper, a simple and very accurate measurement technique is presented to determine the volumetric or mass flow rate. It is based on the fully-developed turbulent pipe flow, a new analytical universal velocity-profile over the entire pipe section and a single-point measurement. In combination with an optimized straightener this technique has to show minimal pressure loss, very moderate costs and high measuring accuracy compared to LDA-measurements. It is possible to apply the measuring prinicple to nonisothermal gas flows, too.     

Thickness measurements with electron energy loss spectroscopy

Measurements of thickness using electron energy loss spectroscopy (EELS) are revised. Absolute thickness values can be quickly and accurately determined with the Kramers-Kronig sum method. The EELS data analysis is even much easier with the log-ratio method, however, absolute calibration of this method requires knowledge of the mean free path of inelastic electron scattering lambda. The latter has been measured here in a wide range of solids and a scaling law lambda approximately rho(-0.3) versus mass density rho has been revealed. EELS measurements critically depend on the excitation and collection angles. This dependence has been studied experimentally and theoretically and an efficient model has been formulated.     

Concept of a charged fusion product diagnostic for NSTX

The concept of a new diagnostic for NSTX to determine the time dependent charged fusion product emission profile using an array of semiconductor detectors is presented. The expected time resolution of 1-2 ms should make it possible to study the effect of magnetohydrodynamics and other plasma activities (toroidal Alfve?n eigenmodes (TAE), neoclassical tearing modes (NTM), edge localized modes (ELM), etc.) on the radial transport of neutral beam ions. First simulation results of deuterium-deuterium (DD) fusion proton yields for different detector arrangements and methods for inverting the simulated data to obtain the emission profile are discussed.     

Determination of key workpiece product characteristics in a machining fixture using uncertainty analysis and loss cost function implementation

The study of fixture related errors is playing an increasingly important role in the improvement of machined part quality. In this work, the locator variability of machining fixtures is analyzed following an uncertainty approach, allowing us to estimate the effect of fixture related geometrical errors on key product characteristics of machined workpieces. Monte Carlo simulation was implemented to generate sufficient variability to determine the expected value of the measuring points of the machined workpiece surface and its related key product characteristic. The results from the Monte Carlo simulation allow sufficient range of values to construct a mathematical relationship between fixture related errors and machined workpiece key product characteristics. Furthermore, the Taguchi loss function is used to investigate the loss cost incurred by a given fixturing uncertainty scheme. An example problem of a prismatic workpiece is presented, where the locating error due to the fixturing system is evaluated in order to know its influence on the workpiece flatness and its associated uncertainty.     

High frequency pressure loss measurements of laminar-turbulent transitional flow

This paper presents a method for identifying, via pressure measurements at frequencies ranging from 10 Hz–142 Hz, laminar-turbulent transitional flow. The fluctuations in pressure can be successfully used as a diagnostic to infer whether the flow is fully laminar, turbulent or transitioning between the two defined regions. The critical Reynolds number of a flow can be determined from the diagnosis of the pressure loss data at high-frequency when monitored with respect to time. With sufficient resolution of the data, the swift movement between laminar and turbulent flow can be witnessed.     

Scintillator-based diagnostic for fast ion loss measurements on DIII-D

A new scintillator-based fast ion loss detector has been installed on DIII-D with the time response (>100?kHz) needed to study energetic ion losses induced by Alfve?n eigenmodes and other MHD instabilities. Based on the design used on ASDEX Upgrade, the diagnostic measures the pitch angle and gyroradius of ion losses based on the position of the ions striking the two-dimensional scintillator. For fast time response measurements, a beam splitter and fiberoptics couple a portion of the scintillator light to a photomultiplier. Reverse orbit following techniques trace the lost ions to their possible origin within the plasma. Initial DIII-D results showing prompt losses and energetic ion loss due to MHD instabilities are discussed.     

Obstacle detection using multi-sensor fusion

This paper presents an obstacle detection approach for blind pedestrians by fusing data from camera and laser sensor.For purely vision-based blind guidance system,it is difficult to discriminate low-level obstacles with cluttered road surface,while for purely laser-based system,it usually requires to scan the forward environment,which turns out to be very inconvenient.To overcome these inherent problems when using camera and laser sensor independently,a sensor-fusion model is proposed to associate range data from laser domain with edges from image domain.Based on this fusion model,obstacle＇s position,size and shape can be estimated.The proposed method is tested in several indoor scenes,and its efficiency is confirmed.     

虚拟企业环境下过程融合及产品开发项目协调

提出了虚拟企业产品设计过程融合的思想,以及面向虚拟企业的设计过程融合与设计活动集成体系结构。该体系结构在任务分解与资源匹配,过程融合、管理与协作,设计任务执行以及对象与版本管理四个层次上,捕捉设计过程中内在的动态特性。基于设计过程动态建模描述虚拟企业环境下过程融合设计流模型,支持虚拟企业环境下敏捷设计流管理,统一组织和管理设计过程、活动及资源,实现虚拟企业环境下产品设计过程分析、优化与动态重构。最后,从三个方面讨论了虚拟企业环境下分布式并行协同产品开发项目的协调问题。     

Photon flux measurements using calorimetry

A simple photometric calorimeter has been constructed, consisting of a vacuum-jacketed cell equipped with flat quartz windows to admit incident light, a thermistor probe to monitor temperature change, and a resistance heater for calibration. An optically dense, photochemically inert solution inside the cell absorbs incident radiation, converting it quantitatively into heat. The calorimeter gives photon flux measurements in agreement with ferrioxalate actinometry at 366 and 436 nm. It has a sensitivity of 2x10(15) photons/s and is useful throughout the optical spectral range.     

Viscometer using drag force measurements

A robust and precise viscometer using the forces exerted by a laminar flow inside a small duct is presented: the force is measured on a long cylindrical sensor dipped into the flow. Two devices of respective volumes 1.4 and 0.031?ml have been realized, demonstrating that the technique is usable with small fluid volumes. Several Newtonian and non-Newtonian fluids have been tested at shear rates ranging from 0.3 to 10?s(-1) for the first device and from 85 to 2550?s(-1) for the second one. For Newtonian fluids, of viscosities ranging from 10(-3) to 0.1?Pa?s, the linear response of the device has been verified and a 90% agreement with the values provided by commercial rheometers is obtained. For non-Newtonian polymer solutions, the variation of the force with the flow velocity allows one to determine the dependence of the viscosity on the shear rate. Two shear thinning polymer solutions with a power law behavior at intermediate shear rates have been investigated and their rheological parameters have been determined.     

Transient measurements using thermographic phosphors

The decay of thermographic phosphors has been used to measure temperature in a wide variety of applications. Because measurements of a single temperature are obtained from intensity decay in time, the use of phosphors is predicated on the fact that the temperature does not change during the decay. This may not be valid in some engineering applications. A new model for phosphor data reduction designed to recover transient effects is presented. A heated wire experiment is used to determine the efficacy of the approach. Results for a particular microsecond phosphor indicate that transients can be resolved, but not to a great deal of accuracy. Nevertheless, the steady model predicted temperatures that were 10 degrees C off compared to the transient model during high heating.     

Possibility of a high-resolution nuclear radiation detector using a superconductor: I. Mean energy loss per excess quasiparticle

In order to study the application of superconductors as nuclear radiation detectors, estimation of the mean energy loss ϵ by radiations per excess quasiparticle in a superconductor has been attempted by taking into consideration the energy shared by the lattice. A detailed discussion on the energy loss processes of quasiparticles created by incident radiations is presented for the first time. It has been found that the upper limit of ϵ is 4 Δ, where Δ is half of the gap energy, but this value is expected to be further reduced. The present result indicates that, as far as ϵ is concerned, superconductors are applicable to a high-resolution nuclear radiation detector.     

Recent interferometric measurements using stabilized lasers

Recently, stabilized lasers have been developed and have begun to have wide use in industrial metrology, particularly in the accurate measurement of length. This paper² reviews recently-developed wavelength-stabilized lasers, the methods of interferometric measurement of length, and discusses several other areas of laser application to high-accuracy industrial measurement.     

基于D-S证据理论的产品多信息融合标识失效补救方法

针对离散制造企业生产环境和工艺的复杂性容易引起Data Matrix二维符号标记的磨损、污染和腐蚀而发生标识失效的问题,提出一种基于D-S证据理论的产品多信息融合标识失效补救方法。分析了产品物理与制造过程中多源信息之间的关联和数据结构,建立了离散制造产品零散与不完整多源信息的数学模型;设计了改进的变异系数加权法,并采用基于类中心的变权欧式距离法对失效标识产品特征和历史数据库进行相似性测度计算;通过D-S证据理论对失效标识的产品特征层进行融合辨识。实验结果表明,该方法能够较好地恢复补救产品失效的标识。     

基于DCT变换的图像融合方法研究

提出了一种基于离散余弦变换(DCT)以及一种结合小波变换与DCT变换的图像融合新方法。前者将源图像进行分块DCT变换,依据DCT系数的高频能量,对源图像的对应区域进行融合。后者利用DCT系数的高频能量对小波分解后得到的低频子图进行融合,同时以此为依据对小波最高分解层的小波高频系数进行选择,其他分解层的小波高频系数依据最大局部方差准则进行融合。依照平均误差、峰值信噪比以及均方根误差等客观评价标准,将新方法与其他常用的基于小波变换或DCT变换的融合方法进行了比较。实验结果表明,结合小波变换与DCT变换的图像融合新方法获得的融合效果优于其他方法。该方法与常用的基于小波变换的融合方法相比,其平均误差减少了40.8%~69.5%,峰值信噪比提高了9.9%~15.6%,均方根误差减少了34.8%~47.5%,评价结果与目视效果相吻合,表明该方法能有效地提高图像融合的质量。基于DCT变换的图像融合新方法的融合效果仅次于结合小波变换与DCT变换的图像融合新方法且其计算量相对较少,适用于实时处理。