Measurement Capabilities Research Articles

Flexible Strain Sensors with Ultra-High Sensitivity and Wide Range Enabled by Crack-Modulated Electrical Pathways

Abstract This study presents a breakthrough in flexible strain sensor technology with the development of an ultra-high sensitivity and wide-range sensor, addressing the critical challenge of reconciling sensitivity with measurement range. Inspired by the structure of bamboo slips, we introduce a novel approach that utilises liquid metal to modulate the electrical pathways within a cracked platinum fabric electrode. The resulting sensor demonstrates a gauge factor greater than 108 and a strain measurement capability exceeding 100%. The integration of patterned liquid metal enables customisable tuning of the sensor’s response, while the porous fabric structure ensures superior comfort and air permeability for the wearer. Our design not only optimises the sensor’s performance but also enhances the electrical stability that is essential for practical applications. Through systematic investigation, we reveal the intrinsic mechanisms governing the sensor’s response, offering valuable insights for the design of wearable strain sensors. The sensor’s exceptional performance across a spectrum of applications, from micro-strain to large-strain detection, highlights its potential for a wide range of real-world uses, demonstrating a significant advancement in the field of flexible electronics.

A Dual-Parametric G-Type Coaxial Thermocouple With Superior Thermal Measurement Capabilities

A Dual-Parametric G-Type Coaxial Thermocouple With Superior Thermal Measurement Capabilities

COMPARISON OF CONFOCAL SENSOR FOR DIAMETER MEASUREMENT WITH MEASURING PROBE

The measurement and inspection of products and their dimensions in industry plays an important role in determining the quality of a product. Correct measurement is a key factor in production. Many companies are subject to stringent safety standards and specific product requirements. Accurate measurement ensures compliance with these guidelines, avoiding fines, penalties and legal complications. Effective measurement processes can identify inefficiencies, defects and areas for improvement, leading to cost savings. By detecting defects early in the production cycle, manufacturers can reduce waste and optimize resource utilization thereby reducing overall production costs. A fundamental principle of good measurement is to ensure that the measuring instruments are suitable for the specific application and that they meet the measurement requirements for the measurement parameter. The objective of the experiment is to verify and compare the measurement capability of a confocal chromatic sensor against a measurement probe used in production. The parameter to be measured is the diameter, since the correct diameter plays an essential role in the production of shafts or other cylindrical products. The results contained in the thesis highlight the importance and differences between the different measuring devices and the qualification to use the measurement of a given parameter.

Correction of Sensible Heat Flux from Flux-Gradient Method to Eddy Covariance Method Based on Multi-Layer Perceptron

Abstract. Understanding surface-atmosphere interactions is critical for environmental and meteorological studies. Sensible heat flux, a key component in this interaction, is typically measured using methods such as Eddy Covariance (EC) and Flux-Gradient (FG). The EC method, known for its high temporal resolution and direct measurement capabilities of wind speed, temperature, and humidity changes, requires the use of expensive and complex equipment, making it costly and challenging to implement. On the contrary, the FG method is more accessible and economical, relying on simpler instruments, but often lacks the precision of the EC method. To harness the benefits of both methods, this article uses the Multi-Layer Perceptron (MLP) machine learning method to enhance the accuracy of the FG method's sensible heat flux calculations. Through the MLP model, this paper aims to determine the optimal parameter settings for the specific measurement environment, thereby improving the FG methods accuracy. The data was measured from Guandu Village, Anhui Province, China. This research seeks to demonstrate that the trained MLP model can be applied to similar measurement environments, thus enhancing the FG method's applicability and precision.

Autonomous Vibrationless Temperature-Controlled Cryosystem for Optical Studies with a Spectroscopic Ellipsometer

Introduction. Ellipsometry is a highly sensitive, non-destructive optical method used to study the optical and structural properties of materials and thin films.Problem Statement. At the Institute of Semiconductor Physics of the National Academy of Sciences of Ukraine, the first in Ukraine serial spectroscopic ellipsometer SE-2000 (manufactured by SEMILAB Ltd., Hungary) has been employed for research, but its measurement capabilities are currently limited to room temperature.Purpose. This research aims to expand the functionality of the SE-2000 by creating a temperature-controlled cryosystem that operates within a temperature range from –195 оC to +80 оC (approximately 80—353 K).Materials and Methods. An autonomous, precision, vibrationless, cryosystem has been designed and manufactured for low-temperature optical investigations in reflection mode, based on a gas-flow cryostat. The cryosystem includes a cryostat, a microprocessor temperature controller, and an adjustment table.Results. The cryostat operates on a gas-flow principle. A laminar gas flow is generated by excess pressure achieved through the heating of cryogenic liquid by a heater-evaporator in the feeder tank. The flow intensity is regulated by adjusting the power supplied to the heating element, eliminating vibrations in the cryostat and sample. The heat exchange chamber is positioned at the top of the nitrogen tank, with the test sample mounted in horizontal plane. Incident and reflected light beams interact with the sample from the upper hemisphere. Sample positioning is adjustable via translational motion along three Cartesian coordinates and by tilting the cryostat with the help of the adjustment table.Conclusions. This system is suitable for use in optical devices that operate in specular reflection mode, with access to the sample surface from the upper hemisphere.

Single-shot quantitative differential phase contrast microscope using a single calcite beam displacer

This paper presents the development of a single-shot, partially spatially coherent quantitative differential phase contrast microscopy (Q-DPCM) system. The optical scheme comprises a polarizer, lenses, calcite beam displacer, and analyzer, which can be seamlessly integrated to an existing bright-field microscopy system, transforming it into a Q-DPCM system. It utilizes a partially spatially coherent light source, enabling single-shot quantitative differential phase recovery of the specimens with high spatial phase sensitivity. It generates highly sensitive quantitative differential phase images of the specimens along one direction, like a gradient light interference microscopy (GLIM) system, using only a single interferogram. First, we validated the differential phase measurement capability of the system through experiments on polystyrene spheres (diameter 5.2 µm) and HeLa cells. Next, the system is utilized to generate quantitative phase maps of human red blood cells using two orthogonal differential interferograms recorded at two orientations of the calcite beam displacer. Further, the Q-DPCM system is implemented for 1-h time-lapse live cell monitoring, revealing the dynamics of intracellular granules such as nucleolus and lipids in U2OS cells.

Evaluating the Efficacy of Deep Learning Reconstruction in Reducing Radiation Dose for Computer-Aided Volumetry for Liver Tumor: A Phantom Study.

The purpose of this study was to compare radiation dose reduction capability for accurate liver tumor measurements of a computer-aided volumetry (CADv) software for filtered back projection (FBP), hybrid-type iterative reconstruction (IR), mode-based iterative reconstruction (MBIR), and deep learning reconstruction (DLR) at a phantom study. A commercially available anthropomorphic abdominal phantom was scanned five times with a 320-detector row CT at 600 mA, 400 mA, 200 mA, and 100 mA and reconstructed by four methods. Signal-to-noise ratios (SNRs) of all lesions within the arterial and portal-venous phase inserts were calculated, and SNR of the lesion phantom was compared with that of all reconstruction methods by means of Tukey's honestly significant difference (HSD) test. Then, tumor volume (V) of each nodule was automatically measured using commercially available CADv software. To compare dose reduction capability for each reconstruction method at both phases, mean differences between measured V and standard references were compared by Tukey's honestly significant difference test among the four different reconstruction methods on CT obtained at each of the four tube currents. With each of the tube currents, SNRs for MBIR and DLR were significantly higher than those for FBP and hybrid-type IR (p < 0.05). At the arterial phase, the mean difference in V for the CT protocol obtained at 600 or 100 mA and reconstructed with DLR was significantly smaller than that for others (p < 0.05). At the portal-venous phase, the mean differences in V for the CT protocol obtained at 100 mA and reconstructed with hybrid-type IR, MBIR, and DLR were significantly smaller than that for FBP (p < 0.05). Findings of our phantom study show that reconstruction method had influence on CADv merits for abdominal CT with not only standard but also reduced dose examinations and that DLR can potentially yield better image quality and CADv measurements than FBP, hybrid-type IR, or MBIR in this setting.

Impact of light polarization on laser speckle contrast imaging with a custom phantom for microvascular flow

Laser speckle contrast imaging (LSCI) is a non-invasive, powerful, and cost-effective imaging technique that has seen widespread adoption across various medical fields, particularly for blood flow imaging. While LSCI provides physicians with valuable insights into changes or occlusions in blood flow, the technique is susceptible to various factors and parameters that can impact measurement sensitivity and signal-to-noise ratio (SNR). These include the scattering of light, which can affect the quality and reliability of the LSCI data. The polarization of light holds significant promise to enhance the performance of LSCI. In this study, we employed polarization manipulation of light to investigate its impact on the performance of LSCI for measuring flow. Focusing on the application of LSCI in microcirculation within capillaries, we examined the effect of polarization control on the technique's flow measurement capabilities using a custom-designed phantom system. This phantom consisted of three tubes with inner diameters of 1.1 mm, 1.6 mm, and 2.8 mm, embedded in a polydimethylsiloxane (PDMS) matrix with optical properties similar to biological tissue. By manipulating the polarization of both the incident and reflected light, alternating between parallel and perpendicular states, we compared the performance of our LSCI system in detecting flow for different tube diameters and depths within the phantom. Our study revealed that while depth is a critical parameter influencing flow detection using LSCI, employing perpendicular polarization (between incident and reflected light) resulted in the lowest measurement error and highest SNR compared to parallel polarization and the absence of polarization control.

Beam emission spectroscopy diagnostic design and capabilities for two-dimensional turbulence measurements on Wendelstein 7-X

A beam emission spectroscopy (BES) diagnostic is designed for studying two-dimensional turbulent dynamics by measuring the Doppler-shifted Balmer-Alpha emission (n = 3 → 2) from neutral heating beams on Wendelstein 7-X (W7-X) stellarator. The BES viewing geometry has been determined in the conceptual design previously. However, the small Doppler shifts and small optical throughput compared to a typical BES diagnostic demand dedicated efforts on the optical assemblies and the detector module for the BES system. We present the detailed opto-mechanical design and specifications of BES, including a customized neutral beam viewing optical system, a semi-telecentric optical assembly, and a detector module for electronic amplification. The point spread function is calculated using the pyFIDASIM code with experimental parameters and W7-X magnetic configurations to estimate the BES spatial resolution and beam intensity. The as-manufactured interference filter is applied for the spectral isolated beam radiance calculation. Result shows that the BES system is capable of measuring the ion-scale turbulence for k ⊥ ρ i ≤ 0.4 at r/a = 0.75 with reasonable spatial and wavenumber resolutions. An integrated detector module is fabricated where two 8×4 avalanche photodiode detectors (APD) are embedded into the custom-designed pre-amplifier circuit to gain signals to the desired level. The detector noise measurement is performed and the signal-to-noise ratio (SNR) is evaluated. A detectable fluctuation level can be achieved as low as ñ e /n e ≈ 0.5% at frequency f ≤ 400 kHz with a bandwidth of 1 MHz.

Predominantly electric storage ring with nuclear spin control capability

A predominantly electric E&m storage ring, with weak superimposed magnetic bending, is shown to be capable of storing two different particle type bunches, such as helion (h) and deuteron (d), or h and electron (e -), co-traveling with different velocities on the same central orbit. Rear-end collisions occurring periodically in a full acceptance particle detector/polarimeter, allow the (previously inaccessible) direct measurement of the spin dependence of nuclear transmutation for center of mass (CM) kinetic energies (KE) ranging from hundreds of keV up toward pion production thresholds. With the nuclear process occurring in a semi-relativistic moving frame, all initial and final state particles have convenient laboratory frame KEs in the tens to hundreds of MeV. The rear-end collisions occur as faster stored bunches pass through slower bunches. An inexpensive facility capable of meeting these requirements is described, with several nuclear channels as examples. Especially noteworthy are the e+/--induced weak interaction triton (t) β-decay processes, t + e + → h + ν and h + e - → t + ν. Experimental capability of measurement of the spin dependence of the induced triton case is emphasized. For cosmological nuclear physics, the experimental improvement will be produced by the storage ring's capability to investigate the spin dependence of nuclear transmutation processes at reduced kinetic energies compared to what can be obtained with fixed target geometry.

An improved subpixel measurement method for piezoelectric ceramic driving characteristics based on particle filter

Microscopic vision displacement calculation is crucial for its high precision and non-contact nature in measuring piezoelectric ceramic displacement. However, the inefficient global search limits its effectiveness. This paper proposes an improved sub-pixel algorithm (GKF-PFBM) based on particle filtering. Firstly, particle filtering (PF) is combined with block matching (BM) to enhance matching efficiency and accuracy by replacing global search with particle state prediction and update. Then, subpixel interpolation using a Gaussian kernel function (GKF) is better adapted to nonlinear variations, handling high-frequency variations while preserving clear edges, thereby improving interpolation accuracy. Finally, a high-precision experimental platform is used to measure the driving characteristics of piezoelectric ceramics. Experimental results show that the mean errors of the GKF-PFBM algorithm and the bilinear interpolation algorithm (BI-BM) are 0.0032pixels and 0.1269pixels, respectively. The average hysteresis displacement error was measured to be approximately 12 nm by this method, verifying its precise non-contact measurement capability.

3D shape measurement method for high-reflective surface based on a color camera

Fringe projection profilometry (FPP) has been widely utilized in many fields due to its non-contact, high accuracy, high resolution and full-field measurement capabilities. However, the limited dynamic range of the camera sensor can result in overexposure of high-reflective parts in industrial production measurement. To effectively solve the above issue, this paper proposes a 3D shape measurement method for the high-reflective surface based on a color camera. Firstly, the optimal exposure time for the low-reflective region is estimated using the relationship between the standard variance of the phase error and the modulation. Twelve blue phase-shifted fringe patterns and a uniform blue image are utilized to obtain 3D shape of high-reflective surface. Secondly, captured images are separated into red, green and blue components. The fused Gaussian low-pass filtering method with different cut-off frequencies is used to filter and denoise the green or red components and the true intensity of the blue component in the saturated regions is calculated by the unsaturated intensity of the green or red components based on the calibrated crosstalk matrix. Then the image in saturated regions is fused and normalized with the unsaturated region. The absolute phase obtained from the fused normalized fringe patterns is converted into 3D data. Finally, experiments have been carried out on measuring. The experimental results show that the proposed method is capable of obtaining the 3D shape of the surface of a high-reflective object with fewer patterns and high measurement accuracy.

Senswing: A Force Sensing Wing for Intelligent Flapping-Wing Aerial Vehicles—Wing Design and Comprehensive Evaluation of Force Sensing Capabilities

This paper proposes a force-sensing wing, Senswing, to enhance the intelligence of flapping-wing aerial vehicles (FWAVs). Force perception is a crucial capability for robots to interact safely and effectively in unknown environments. However, FWAVs perform flapping motions with significant acceleration and deceleration, which can cause the flexure element inside force sensors to deteriorate due to repeated loading or even fail due to impulsive forces. To address this, we constructed a force measurement system by attaching 16 strain gauges directly to the wing root while maintaining high rigidity. We confirmed that the external force measurement capability closely matched the values obtained by a six-axis force sensor, with almost no error. Additionally, when measuring aerodynamic forces during wing flapping, the sensor could detect differences in wind speed even during flapping. With this sensor, FWAVs can achieve in-flight measurement of thrust and lift through a force-sensing system.

Fiber Bragg Grating-based sensor for measuring supersonic inlet terminal shock at different angles of attack

This study presents a multipoint pressure measurement system using fiber Bragg grating sensors to detect terminal shock positions. The system consisted of a fiber optic string encapsulated with multiple diaphragm-based fiber Bragg grating sensors, capable of detecting flow field characteristics at fourteen different axial positions of the inlet. The calibration results indicated a sensitivity of 46.47 pm/kPa, a linear correlation coefficient of 0.9997, and a maximum repeatability error below 1.44%. In supersonic wind tunnel tests, the system effectively measured pressure and located the terminal shock across varying angles of attack and throttling degrees. The maximum difference compared to conventional pressure sensors was 4.7%, and the terminal shock positioning error was limited to 1.2%. Overall, the system has robust multipoint measurement capabilities and is priced at only one-tenth of traditional sensors, showing great potential in the field of inlet measurements.

Rb2InCl5·H2O doped with Te4+ for fluorescence thermometry and coordinated water-related structural phase transformation.

Here, we synthesized Rb2InCl5·H2O with x Te4+ doping by the coprecipitation method, which converts the original nonluminance for pure Rb2InCl5·H2O into orange luminescence ascribed to Te4+ incorporation with an emission peak at 648 nm and a full width at half maximum of 142 nm (420.3 meV) at room temperature. The photoluminescence (PL) lifetime of Te4+-doped Rb2InCl5·H2O exhibits a strong temperature dependence, with a maximum absolute sensitivity (SA) of 12 × 10-3 K-1 at 260 K and a relative sensitivity (SR) of 3.5%K-1 at 300 K, demonstrating its capability for non-contact remote temperature measurement. Additionally, we capture the dynamic changes of coordinated water with temperature in Rb2InCl5·H2O through temperature-dependent Raman spectroscopy, analyze the resulting structural phase transformation associated with coordinated water, and investigate the reversibility of this phase transformation.

DMSCTS: Dynamic measurement scheme for the containers-hybrid-deployment based on trusted subsystem

Hybrid deployment of containers with different kernel types offers a novel solution for cloud service providers. While extensive research has been conducted on shared kernel containers, the security risks associated with diverse kernel types in hybrid deployment scenarios present more complex challenges. Establishing trusted relationships from hardware to containers for hybrid deployment has become a primary concern. Additional challenges include the lack of measurement and communication methods for independent kernel containers and insufficient dynamic measurement capabilities for containers. To address these issues, we propose a novel approach of achieving secure hybrid deployment of containers through the provision of trusted assurance in three layers: container infrastructure, container application environment, and container runtime. We propose the corresponding measurement schemes for each trust layer. Through functional verification and performance evaluation, we demonstrate that our architecture exhibits improved feasibility and effectiveness.

Stokes-based analysis for the estimation of 3D dipolar emission

We provide a general description of the measurement capabilities of systems that probe the 3D state of polarization of light emitted by a dipole or a collection of dipoles. This analysis is based on a generalization of the Stokes parameters for 3D polarization, and its goal is to provide insight into what constitutes a good measurement system under specific circumstances, through the definition of appropriate merit functions. Three cases are considered: the general case of arbitrary states of 3D polarization, the special case of 3D linear full or partial polarization states, and the even more specific case of linear dipoles that wobble with rotational symmetry around a central direction. Note that the latter two cases are of interest in fluorescence microscopy. The analysis presented here is illustrated by applying it to two different approaches used commonly in orientation microscopy: PSF engineering and ratiometric measurements.

A comparison of procedure-related adverse events between two right ventricular leadless pacemakers.

The Medtronic Micra VR and Abbott AVEIR VR are the leadless pacemakers (LPM) currently available in the United States (US). Micra VR employs fixation tines and the AVEIR VR uses an active fixation helix. Micra VR requires fixation before electrical measurements are obtained, while R-waves may be mapped by AVEIR VR without fixation. Little comparative data is available for these LPMs. Accordingly, we compared the incidences of procedure-related major adverse clinical events (MACE) and device problems in the US for Micra VR and AVEIR VR during 2022-2024. We searched the FDA's Manufacturer and User Facility Device Experience (MAUDE) database for US reports of MACE and device problems that were filed from April 2022 to December 2023 for AVEIR VR, and from June 2022 to April 2024 for Micra VR. Totals for US-registered LPM implants were obtained from the manufacturers' product performance reports. During the study period, 5990 AVEIR VR and 10 940 Micra VR implants were registered in the US. We found 305 MAUDE reports for AVEIR VR (5.1%), versus 541 MAUDE reports for Micra VR (4.9%) (p = .702). The incidence of MACE was 0.72% (43/5990) for AVEIR VR versus 0.59% (65/10 940) for Micra VR, (p = .387). The incidences of procedure-related death, cardiac perforation. cardiac arrest, emergency pericardial drainage or reparative surgery were similar for both LPMs (p > .05). Micra VR had more unacceptable thresholds requiring LPM replacement compared to AVEIR VR (95;0.9% vs. 24;0.4%; p = .001). AVEIR VR had a statistically higher incidence of device dislodgement during (32) and after (21) implant compared to Micra VR (53 (0.9%) vs. 46 (0.4%), p < .001). Micra VR and AVEIR VR have similar procedural safety profiles, including the incidences of death and perforation. However, device problems differed significantly, possibly related to their design differences. Compared to Micra VR, AVEIR VR appears to have an advantageous threshold measurement capability but is more prone to device dislodgement.

Usefulness and limitations of various detector systems for estimation of 131I thyroid activity following an RN event

Following a radiological or nuclear (RN) event, rapid measurement of131I in members of the public is of utmost importance, and much equipment is needed for a high throughput. In this study, three gamma cameras (GCs), two thyroid uptake meters (TUMs) and one whole-body counter (WBC) were calibrated for activity measurements of131I in the thyroid. Minimum detectable activity was derived for the GCs, the TUMs and the WBC giving that a committed effective dose (CED) in the interval 2.0-85μSv, 13-700μSv and 0.52-6.4μSv, and thyroid absorbed doses in the interval 0.075-2.1 mGy, 0.48-17 mGy, and 0.020-0.15 mGy, respectively, can be assessed for children, adolescents, and adults. These numbers are based on 10 min measurement, performed at 1, 3 and 7 d after intake, and the CED includes intake by ingestion and inhalation of aerosols Type F, with an activity median aerodynamic diameter of 1μm. For a fractional signal loss of 63% due to dead time, a CED up to 2.0, 84 and 3.6 Sv and thyroid absorbed dose up to 47 Gy, 2000 Gy and 88 Gy for the three systems, respectively, can be assessed for children and intake by ingestion as a worst-case scenario in terms of CED, measured 7 d after intake. This study demonstrates the potential and limitations of using equipment readily available at larger hospitals for estimation of131I content in thyroid, which could increase the measurement capability following an RN event.

Clinical application of an optimized reference measurement procedure for serum digoxin using bracketing calibration method by ID-LC-MS/MS.

Digoxin, a cardiac glycoside, is widely used in the treatment of cardiovascular diseases. Due to its narrow therapeutic range, precise monitoring of its blood concentration is essential. Areference measurement procedure (RMP) is pivotal for ensuring result accuracy and comparability. The RMP for serum digoxin by ID-LC-MS/MS was optimized with sample pre-treatment and detection processes, and the bracketing calibration method was used, which facilitates more accurate measurement, especially for extreme concentrations. The performance of this optimized RMP was thoroughly evaluated. The limit of detection (LoD) was 0.05 ng/mL (0.06 nmol/L) and the lowest limit of quantification (LLoQ) was 0.10 ng/mL (0.13 nmol/L). The intra- and inter-assay imprecisions were 2.24%, 2.51%, 1.40% and 1.72%, 1.65%, 0.97% at 0.5, 2.0, 5.0 ng/mL, respectively. Recoveries were 99.63 to 101.42% and thelinear response ranged from 0.1 to 10.0 ng/mL. The relative bias was 0.41% and 2.00% of our results compared with the median of all participating reference laboratories for IFCC-RELA (External Quality Assessment Scheme for Reference Laboratories in Laboratory Medicine) 2023A and 2023B. The uncertainty, calibration and measurement capability (CMC) of this method were also evaluated. The optimized RMP was applied in the Trueness Verification Plan of Southern China, which indicates significant differences among clinical systems, highlighting the need for standardization efforts. In addition, two commonly used clinical systems which employed immunoassay methods were compared with this optimized RMP, and 26 individual serum samples were analyzed. The good correlations indicate the feasibility of standardization for serum digoxin. The optimized RMP serves as an accurate reference baseline for routine methods, aiming to enhance the accuracy and precision of measurements in clinical laboratories.