Uncertainty quantification is crucial for any measurement technique. The present work aims at validating a priori estimates of displacement uncertainties. Images acquired prior to fourteen thermomechanical tests were analyzed via FE-based stereocorrelation to determine actual displacement uncertainties, which were compared to a priori estimates. For the studied experimental database, a very good agreement

Nano-superconducting quantum interference devices (nano-SQUIDs) with high energy sensitivity and spatial resolution are essential in many applications such as single spin detection, nano-electromechanical vibration detection and microscale magnetic imaging. This paper studies a Dayem-type niobium nano-SQUID using focus ion beam milling technology. The device has two 42 nm × 60 nm nano-bridges and an

Intelligent fault recognition has been a hot topic in the area of mechanical fault detection. However, it is difficult to collect sufficient monitoring data to represent the various kinds of faults and support network training. This paper proposes a convolutional adversarial auto-encoder (AE) for mechanical fault recognition with unseen classes via one-class classification. The generator is established

The failure of rotating machinery affects the quality of the product and the entire production process. However, it usually suffers the subsequent deficiency that the hyperparameters of the fault diagnosis model require constant debugging. This paper proposes a deep condition feature learning approach for rotating machinery based on modified multi-scale symbolic dynamic entropy (MMSDE) and optimized

This work presents the design of a modified Vivaldi antenna, a metamaterial structure and their combined utilization for tuning the gain. Two triangular shaped conducting patches are used to form a (5 mm × 5 mm) unit metamaterial structure, which is used on the Vivaldi antenna to enhance the bandwidth and the gain. The proposed antenna has a −10 dB bandwidth of 17.36 GHz ranging from 3.3 to 21.6 GHz

Although the tightly integrated inertial navigation system/ultra wide band (INS/UWB) improves the localization accuracy, it suffers from UWB distance outage. In order to reduce the outage effect on the position accuracy, in this paper we propose using a novel decision tree (DT)-extended finite impulse response (EFIR) filter. When all the UWB distances are available, the EFIR filter tightly fuses the

Geometric distortion is inevitable in facilities using x-ray image intensifiers. When the induced distortion pattern varies over time, each recorded frame should be corrected accordingly, which is the case in conventional C-arm imaging, for example. This demonstrates the need for reliable and easy-to-use, projection-angle-dependent correction methods. In the present work, we demonstrate such a dynamic

We report new developments in instrumentation and techniques for both acoustic (speed of sound) and radiometric primary thermometry methods. These include both new cylindrical resonators for extending acoustic gas thermometry to higher temperatures and absolute radiation thermometers incorporating InGaAs detectors to extend primary radiometry to lower temperatures than can be achieved using Si-detector

The paper describes a novel technique for measuring the velocity of fast flying objects. The technique utilises a series of simple single-use screens which are placed along the expected flight path. The projectile interaction with the screen generates a flash of light which is captured by an optical fibre connected to the light detecting device. The velocities are calculated from the signal arrival

This article describes the successful implementation of a structured UV light field, generated from a modified LCD projector, to excite pressure-sensitive paint (PSP) and measure surface shape simultaneously without the need to compromise the PSP by mechanical degradation of the coating. Using commercially available hardware, results were gathered in a Mach 5 wind tunnel, showing the expected pressure

This paper focuses on the dispersion characteristic of interface waves and the detection of interlaminar defects in multilayered pipes. The interface waves propagating along axial and circumferential directions are simplified as strain problems of planes ( r, z ) and ( r, θ ), respectively. The axial interface wave is well suited to axial localization of the defect, just as the circumferential interface

The characterization of nuisance parameters in digital silicon photomultipliers (SiPMs) is important to their understanding and future development. Methods able to distinguish the types of events are necessary to obtain fair and legitimate measurements. In this work, the zero photon probability (ZPP) method and the time delay (TD) method are used to measure the dark noise of digital SiPMs free from

Ultrasound is typically measured using phase-sensitive piezoelectric sensors. Interest in phase-insensitive sensors has grown recently, with proposed applications including ultrasound attenuation tomography of the breast and acoustic power measurement. One advantage of phase-insensitive detectors, in contrast to conventional phase-sensitive detectors, is that they do not suffer from a narrow directional

In an optically pumped alkali vapor cell with a high density of atoms, the attenuation of the pump light generates a spatially non-uniform distribution of the electronic spin polarization of alkali atoms, which is detrimental to biomagnetism applications of magnetometers as well as the hyperpolarization of noble gas atoms. Therefore, in this study, we propose a new scheme to generate a nearly uniform

In order to determine the thermo-mechanical properties of a complex 3D woven ceramic composite material, an experiment at high and inhomogeneous temperature and its dedicated full-field measurement procedure is developed. 3D tomographic images of the tested sample are captured at different stages of loading in a synchrotron beamline, and an infrared camera captures a side view of the sample as it rotates

As a noncontact, noninvasive medical imaging technique, magnetic induction tomography (MIT) can measure the conductivity distribution inside the human body. Moreover, animal testing is crucial before performing clinical trials. An abdominal subcutaneous injection rabbit model was used to simulate two local conductivity perturbations, that is, (1) injecting a 0.9% NaCl solution and (2) injecting in

Microscopic hyperspectral imaging technology has been widely used in pathological analysis as it can obtain both spatial and spectral information of samples. However, most hyperspectral imaging systems can only capture images in a single field of view. Therefore, an image mosaic is one of the most important steps in a large-scale microscopic hyperspectral imaging system. This paper proposes a microscopic

In this paper, we propose a gas analyzer that uses a quantum cascade laser (QCL) and achieves high sensitivity and gas selectivity with simple configuration and signal processing. Feature quantities are extracted from an absorption-modulated signal, which is obtained by the logarithmic conversion of a detector signal receiving a wavelength-modulated laser light. The extracted feature quantities are

Precision instrument measurement on an unstable platform is a difficult engineering problem, and the commonly used method is to compensate the instrument measurement results through platform attitude estimation. This paper derives a three-dimensional attitude estimation method based on inertial sensors including gyroscope and inclinometer. In order to deal with the inertial sensor noise, low-pass filter

If the problems related to the parts and measurement strategy of Coordinate Measuring Machines (CMMs) are not taken into consideration, temperature variations become the main source of measurement uncertainties. Indeed, they may cause variations in geometry as well as reference point drift. The effect of drift is sometimes minimized by CMM users and is not well quantified in general. The aim of this

In-situ monitoring of soft soil strength development is of great significance in artificial ground freezing (AGF) projects. It can not only help engineers estimate the soil freeze-thaw status, but also provide useful data for predicting and controlling the concurrent adverse effects which may cause serious engineering accidents. As a useful nondestructive testing method, the electromechanical impedance

Virtual measuring instruments are useful tools in surface topography measurement and can be applied for the prediction of measuring results and the determination of measurement uncertainty. For optical measuring instruments, often computationally expensive ray-tracing algorithms are applied. Other models provide an approximation of the transfer behavior based on techniques from signal processing or

The application scenarios of rotating machinery are becoming increasingly complicated due to the rapid development of the manufacturing industry. The remaining useful life (RUL) prediction of rolling bearings has gradually been considered in many industry fields for ensuring the safety and reliability of whole systems. As an effective way to analyze data, the relevance vector machine (RVM) approach

Non-destructive monitoring of metal hardness is important for process monitoring and product quality assessment. In this paper, a partially hardened metal sample is assessed in regards to physical effects using multi-frequency inductance spectroscopy. For this purpose, the influence of change of conductivity, permeability and stress on the inductance spectra are analyzed. To extract the numerical values

In this paper, leakage characteristics of a sealing structure with damage holes are measured, combining super-resolution algorithms with infrared thermography technology. First, leakage tests of a sealing structure with a single-hole and double-hole are conducted, and some original infrared images are operated to locate the leakage position and calculate the leakage rate. Second, different types of

The joint time–frequency (TF) distribution is a critical method of describing the instantaneous frequency that changes with time. To eliminate the errors caused by strong modulation and noise interference in the process of time-varying fault feature extraction, this paper proposes a novel approach called second-order time–frequency sparse representation (SOTFSR), which is based on convex optimization

An on-board vision system is recognized as a promising tool for vehicle early warning and monitoring. Timely accurate estimation of vehicle speed is critical in allowing the on-board vision system to calculate the vehicle location, plan a driving path, and apply emergency brakes to avoid accidents. However, the scene images captured by the vision system always suffer from global motion blur, which

A new concept for probe light intensity stability control and high-frequency modulation based on an acousto-optic modulation in a K-Rb- 21 Ne co-magnetometer is reported. The structure and optical path are ingeniously designed to avoid the interference of zero-order diffraction light. The average rotation rate sensitivity of ##IMG## [http://ej.iop.org/images/0957-0233/32/2/025112/mstabbc8aieqn1.gif]

Rolling bearings are one of the most significant components of much large machinery, and also one of the components prone to failure. Advanced time–frequency analysis (TFA) methods can provide time–frequency (TF) graphs with more significant features that are critical for fault diagnosis of rolling bearings. In this paper, we propose a new TF algorithm, called the multi-synchrosqueezing S-transform

Aiming at the problem that the common rail injector’s early fault characteristics are very weak and susceptible to random noise and other signal interference, this paper proposes a new common rail injector weak fault diagnosis method based on multipoint optimal minimum entropy deconvolution adjusted based on modified grasshopper optimization algorithm optimization algorithm (MGOA-MOMEDA), improved

In this paper a new bubbly flow measurement procedure is proposed which can be used to both detect and quantify some main features of such flows. The proposed procedure is based on the optical scattering behavior of a laser-beam passing through a bubbly flow. A series of experiments are conducted to evaluate the procedure and important parameters involved such as length of bubbly flow, bubble number

A coordinate measuring machine (CMM) is widely used for surface measurement during milling and grinding of workpieces. However, the measurement uncertainty increases with the surface slope for highly steep freeform surfaces. In addition, local features sometimes exist on the surface out of the accessible space of the CMM. This study presents a coordinate measurement method based on stitching multiple

Rotating machinery plays an increasingly crucial role in mechanical systems. For its normal operation, a novel fault diagnosis method is proposed in this paper, using composite multiscale fuzzy distribution entropy (CMFDE) and minimal error of convex hull approximation (MECHA). In this paper, CMFDE is utilized to extract essential information and measure time series complexity for vibration signals

Ultra-wideband (UWB) is essential in precise point positioning (PPP)/inertial navigation systems (INS)/UWB integrated navigation with the advantage of highly accurate observations. However, its accuracy could be affected by its sparse distribution, limited operating distance and low space height. In a dynamic environment, it is not easy to determine its variance precisely for an integrated system.

Industrial ultrasonic tomography (UT) possesses a unique advantage in gas–liquid two-phase distribution measurement and has received broad attention over the past decades. Focusing on a liquid-dominated gas-inclusion distribution reconstruction, we propose the strategy of multi-frequency fusion UT (MFFUT), which comprehensively models the transmission attenuation and self-adaptive fusion of multi-frequency

The high enhancement factor (EF) of surface-enhanced Raman (SERS) probes is an important parameter for high-sensitivity Raman scattering measurement applied to environment control. In this article, we present a SERS probe based on silver nano-structures deposited on silica microsphere surfaces made by the laser-assisted photochemical method and reflection converging mirror for a high EF Raman measurement

RainbowPIV is a recent imaging technology, proposed for time-resolved 3D-3C fluid velocity measurement using a single RGB camera. It dramatically simplifies hardware setup and calibration procedures as compared to alternative 3D-3C measurement approaches. RainbowPIV combines optical design and tailored reconstruction algorithms, and earlier preliminary studies have demonstrated its ability to extract

A single-image nitric-oxide molecular tagging velocimetry (NO-MTV) is reported and employed in a real air driven hypersonic shock tunnel and provided velocities of 3240 ± 170(5.2%) and 3030 ± 160(5.3%) m ##IMG## [http://ej.iop.org/images/0957-0233/32/2/025301/mstabbba2ieqn1.gif] {$\mathrm{s}^{-1}$} , insignificantly different from previous results of 3037 ± 98(3.2%) obtained by an ordinary multi-image

Specific emitter identification (SEI) refers to the process of distinguishing emitter individuals, which is important for electric support measure systems. Traditional SEI methods are based on hand-crafted features and have the problem of low accuracy. A novel convolutional neural network (CNN) approach, named squeeze excitation densely connected residual convolutional network (SEDCRN) approach, is

Intelligent mechanical fault diagnosis algorithms based on deep learning have achieved considerable success in recent years. However, degradation of the diagnostic accuracy and operational speed has been significant due to unfavorable working conditions and increasing network depth. An improved version of ResNets is proposed in this paper to address these issues. The advantages of the proposed network

This study proposes a grid-coil-type transducer to achieve the simultaneous detection of axial and circumferential cracks in the pipeline, reduce the number of permanent magnets in dynamic detection, and improve crack detection efficiency. The proposed system can detect biaxial cracks in the pipeline. Based on Biot–Savart’s Law, a mathematical model is established between the magnetic induction intensity

The principle of operation of a successive approximation type direct displacement to digital converter for a floating-wiper resistive potentiometric sensor, presented earlier, is analyzed in detail to ascertain possible sources of error that can affect the performance of the transducer. Based on the analysis the method is suitably modified to improve its performance. To establish the efficacy of the

We propose a time-of-flight ranging method by measuring the pulse laser phase based on field-programmable gate array (FPGA) digital mixing, in which accurate laser ranging with a total digital system is realized by combining one FPGA chip with a simple laser transmitting and receiving circuit. The system has the advantage of simple structure, reliable operation, low manufacturing cost and easy integration

In this work, we examine the accuracy of the geometric error calibration of machine tools using a laser tracer, via the multilateration or sequential multilateration principle. An uncertainty analysis of geometric errors or target point coordinates, based on the Monte-Carlo method, is often adopted to assess the accuracy of measurement results. However, this approach is not comprehensive, and can be

A sprayable fast-responding pressure-sensitive paint (fast-PSP) has been developed to measure time-resolved small pressure fluctuation on model surfaces. To realize PSP with fast response, high robustness, and high luminescence intensity, we have developed a novel ruthenium complex-based fast-PSP. The binder layers of the proposed fast-PSP were prepared by mixing room-temperature-vulcanizing silicone

BaTiO 3 crystal films, possessing advanced electrooptic (EO) properties, have spurred a broad interest in research and development of EO modulators for fiber-optic communications. However, the EO coefficient is still at uncontrollable and unoriented states despite it playing a crucial role in developing applicable industrial devices. In this work, accurate measurements of the EO coefficient ##IMG##

This paper describes the development of heated double-sided thin film gauge configurations for transient heat transfer measurements. By heating the substrate it is possible to measure the heat flux over a range of surface temperatures and deduce the adiabatic wall temperature and the external heat transfer coefficient. The accuracy of the measurement depends on the stability of the regression of heat

Pressures are often measured in fast transient regimes, even if the transducers are not calibrated in dynamic regimes. If the solutions proposed for primary calibration of the dynamic response of pressure sensors must be fully recognised, secondary methods are also needed to disseminate the standard to final users. A method for assessing measurement uncertainty, carried out by comparison with a reference

The increasing use of microfluidics in industrial, biomedical, and clinical applications requires a more and more precise control of the microfluidic flows and suspended particles or cells. This leads to higher demands in three-dimensional and automated particle tracking methods, e.g. for use in feedback-control systems. General defocusing particle tracking (GDPT) is a 3D particle tracking method based

A novel laser interferometric technique for measuring the variation of the refractive index with concentration and temperature is presented. The technique is based on the principle of ‘absolute scale’ accomplished with a Michelson interferometer. The linear motion of the scanning mirror allows simple extraction of the optical path change inside the Fabry–Perot interferometer. The measurement of the

In-cylinder imaging diagnostics for internal combustion engines provide rich information on the structure and evolution of reaction zone features, which affect both engine out emissions and efficiency. However, the most common analysis of in-cylinder combustion luminosity imaging considers ensemble averaged images, which are not suitable for characterizing processes that vary significantly between

Electrical capacitance tomography (ECT) image reconstruction is an ill-posed inverse problem. Regularization methods are generally employed to solve the ill-posed problem, and the reconstructed image quality is seriously influenced by the selection of the regularization parameter. At present, a same regularization parameter is generally adopted for the whole reconstruction region, but the object region

On-machine inspection (OMI) technology can improve the machining quality and detection efficiency of mechanical parts. The quantity of inspection points in the process of OMI is related to the inspection efficiency and data processing; it also affects the layout of inspection points. In this paper, the concept of surface complexity is proposed to replace the complex calculation of curvature, and the

Soft sensors have become reliable tools for predicting difficult-to-measure quality variables in modern industrial process modeling. Feature representation is a key step to construct accurate soft sensor models. In the past decade, deep learning has shown great capacity of feature extractor for soft sensor modeling. However, most existing deep networks cannot capture quality-related features for output

This paper presents a single-shot phase extraction approach based on a deep convolutional generative adversarial network that generates a phase map and a quality mask from an input fringe pattern image. A novel loss function is proposed, and a large-scale (28 800 samples) real fringe pattern dataset is collected to train the network. The experiments demonstrate that the proposed method achieves significantly

The continuously growing number of micro and nanosatellites launched in recent years has stimulated research institutes and industries to find alternative and less expensive ways to reach Low Earth Orbits. Laser ablation propulsion is one of the most promising launching techniques, even though a dedicated and reliable testing system has not been discussed in literature. We present a simple and dependable

In this paper, we present a novel algorithm for the automatic detection and measurement of Vickers indentation hardness, using image processing. This algorithm uses image segmentation via binarization, automatically evaluating the mean and extreme gray values by means of standard histogram equalization so as to determine the optimal binarization threshold from each input image. We use a morphological

In the underwater environment, the backscattering and attenuation of wavelength-dependent light degrade the quality of underwater vision. Low-quality underwater vision will reduce the accuracy of underwater robot visual navigation and pattern recognition. A novel semi-supervised deep convolutional neural network composed of a supervised learning branch and an unsupervised learning branch is proposed

It is well-known that the minimum spanning tree (MST) is widely used in image segment, edge-preserving filtering, and stereo matching. However, the non-local (NL) filter based on the MST generally results in overly smooth images, since it ignores spatial affinity. In this paper, we propose a new spatial minimum spanning tree filter (SMSTF) to improve the performance of the NL filter by designing a

A new algorithm of a multi-baseline solution (MBS) based on the equivalence principle for precise relative positioning is proposed in this paper. The objective of the solution is to keep the observations independent when eliminating the satellite and receiver’s clock errors. The equivalent differenced observation equations are developed through the equivalent transform. Because of the high-dimension