Search Results (138)

The rapid advancement of materials science is driving the development of emerging advanced materials, such as nanomaterials, composites, biomaterials, and high-performance metals. These materials possess unique properties and offer significant potential for innovative applications across industries. Standardization plays a crucial role in ensuring the reliability, consistency, and comparability of material quality assessments. Although typical material specification standards, which rigidly define allowable characteristic ranges, are well-suited for established materials like steel, they may not be directly applicable to emerging advanced materials due to their novelty and evolving nature. To address this challenge, a distinct approach is required—flexible yet robust testing standards for assessing material quality. This paper introduces scenario-based methodologies, a structured approach to developing such standards, with a particular focus on metrological aspects of measurement methods and procedures. Additionally, self-assessment processes aimed at verifying measurement reliability are integrated into the methodology. These methodologies involve defining target materials and their applications, identifying critical material characteristics, specifying appropriate measurement methods and procedures, and promoting adaptable yet reliable guidelines. To maintain relevance with metrological advancements and evolving market demands, these quality testing standards should undergo periodic review and updates. This approach enhances industrial confidence and facilitates market integration. Full article

This study systematically compares the metrological characteristics of single- exposure, double-exposure, and continuous-exposure holographic interferometry for micro-deformation detection. Results demonstrate that the double-exposure method achieves optimal balance across critical performance metrics through its ideal cosine fringe field modulation. This approach (1) eliminates object wave amplitude interference via dual-exposure superposition, establishing submicron linear mapping between fringe displacement and deformation amplitude; (2) introduces a fringe gradient-based direction detection algorithm resolving deformation vector ambiguity; and (3) implements an error-compensated fusion framework integrating theoretical modeling, MATLAB 2015b simulations, and experimental validation. Experiments on drilled glass samples confirm their superior performance in terms of near-ideal fringe contrast (1.0) and noise suppression (0.06). The technique significantly improves real-time capability and anti-interference robustness in micro-deformation monitoring, providing a validated solution for MEMS and material mechanics characterization. Full article

Attaining dimensional accuracy in CNC-machined parts is essential for high-precision manufacturing, especially when working with materials that exhibit varying mechanical and thermal characteristics. This research provides a thorough experimental comparison of manual and automated metrological systems, specifically the Digital Vernier Caliper (DVC) and Coordinate Measuring Machine (CMM), as applied to five different engineering alloys through five progressively machined axial zones. The study assesses absolute error, relative error, standard deviation, and measurement repeatability, factoring in material hardness, thermal conductivity, and surface changes due to machining. The results indicate that DVC performance is significantly affected by operator input and surface irregularities, with standard deviations reaching 0.03333 mm for Bronze C51000 and relative errors surpassing 1.02% in the initial zones. Although DVC occasionally showed lower absolute errors (e.g., 0.206 mm for Aluminum 6061), these advantages were countered by greater uncertainty and poor repeatability. In comparison, CMM demonstrated enhanced precision and consistency across all materials, with standard deviations below 0.0035 mm and relative errors being neatly within the 0.005–0.015% range, even with challenging alloys like Stainless Steel 304. Furthermore, a Principal Component Analysis (PCA) was conducted to identify underlying measurement–property relationships. The PCA highlighted clear groupings based on sensitivity to error in manual versus automated methods, facilitating predictive classification of materials according to their metrological reliability. The introduction of multivariate modeling also establishes a new framework for intelligent metrology selection based on material characteristics and machining responses. These results advocate for using CMM in applications requiring precise tolerances in the aerospace, biomedical, and high-end tooling sectors, while suggesting that DVC can serve as an auxiliary tool for less critical evaluations. This study provides practical recommendations for aligning measurement techniques with Industry 4.0’s needs for accuracy, reliability, and data-driven quality assurance. Full article

Background and Objectives: The objective of our study was to describe the biopsychosocial profile of individuals diagnosed with axial spondyloarthritis (AxSpA) and to analyze how their clinical characteristics interact with disease activity. Materials and Methods: An observational study was conducted, involving 28 participants diagnosed with AxSpA. We evaluated clinical outcomes (perceived pain, range of motion [RoM], pressure pain threshold [PPT], and proprioceptive acuity), psychosocial outcomes (the Pain Catastrophizing Scale [PCS], Tampa Scale of Kinesiophobia [TSK-11], and the Fear-Avoidance Beliefs Questionnaire [FABQ]), and AxSpA-specific indices (the Bath Ankylosing Spondylitis Metrology Index [BASMI], Bath Ankylosing Spondylitis Functional Index [BASFI], and Bath Ankylosing Spondylitis Disease Activity Index [BASDAI]). Data were analyzed using Spearman’s correlation coefficients and simple and multiple linear regression models. Results: Cervical and lumbar RoM values were reduced compared to established normative values for the general population. Significant associations were found between perceived pain, pain catastrophizing, and FABQ scores with both BASDAI and BASFI (p < 0.05). The interaction between perceived pain and pain catastrophizing (p < 0.001) accounted for 45.7% of the variance in BASDAI, while the interaction between perceived pain and FABQ (p < 0.001) explained 52.1% of the variance in BASDAI. Conclusions: The biopsychosocial profile of patients with AxSpA is characterized by moderate-intensity perceived pain and reduced cervical and lumbar mobility. The observed associations between BASDAI, pain catastrophizing, and fear-avoidance beliefs underscore the influence of psychosocial factors on disease progression. Full article

ISO 25178 part 600:2019 and part 700:2022 introduce a calibration framework based on seven metrological characteristics (MCs) for calibrating optical areal surface measuring instruments. Among these, topography fidelity is a newly defined metrological characteristic that remains a critical yet unresolved challenge in instrument calibration. This paper proposes strategies to address topography fidelity, including a key criterion for selecting suitable instrument setups by comparing slope measurement capability with local surface slopes, as well as methods for investigating the field-of-view homogeneity and directional performance difference along the x- and y-axes. Furthermore, the uncertainty contribution of topography fidelity in surface topography measurements is analysed. The paper also determines the uncertainty associated with the remaining six MCs. Based on the proposed MC-based calibration approach and the corresponding uncertainty contributions, an overall measurement uncertainty model for Sa and Sq parameters is presented. Finally, uncertainty evaluations for Sa and Sq are demonstrated on a challenging surface, where topography fidelity plays a significant role in the measurement uncertainty evaluation. Full article

Narrow-linewidth lasers play a crucial role in nonlinear optics, atomic physics, optical metrology, and high-speed coherent optical communications. Precise linewidth measurement is essential for assessing laser noise characteristics; however, conventional methods are often bulky, costly, and unsuitable for integrated applications. This paper presents a compact and cost-effective delay self-homodyne system for laser linewidth measurement, leveraging a field-programmable gate array (FPGA)-based data acquisition circuit. By employing fast Fourier transform (FFT) analysis, the system achieves high-precision linewidth measurement in the kHz range. Additionally, by optimizing the fiber length, the system effectively suppresses low-frequency and 1/f noise, providing an integrated and efficient solution for advanced laser characterization with enhanced performance and reduced cost. Full article

This paper describes the development and validation of an apparatus for the realization of the triple point of argon (83.8058 K), with a novel automatic pressure control system for the liquid nitrogen cryostat. The automatic pressure controller, together with custom-made software, was developed and tested in the Laboratory for Process Measurement at the Faculty of Mechanical Engineering and Naval Architecture, University of Zagreb (FSB-LPM). Performance testing and characterization of the automatic pressure controller confirmed its suitability for precise and reliable control of gauge pressure in the cryostat. The characteristics and uncertainty of the measurement setup for the realization of the triple point of argon were validated through a bilateral hybrid comparison with the Laboratory of Metrology and Quality at the Faculty of Electrical Engineering, University of Ljubljana (MIRS/UL-FE/LMK). A long-stem quartz-sheathed standard platinum resistance thermometer was used as a transfer standard. The realizations of the International Temperature Scale (ITS-90) were compared in the subrange from the triple point of argon to the triple point of water. The comparison results show that resistance ratio (W) values determined by FSB-LPM at the fixed points of argon and mercury deviate from the MIRS/UL-FE/LMK values, within the determined combined uncertainty of the comparison. Full article

A full-scale geophysical observatory in the North Caucasus, which was established to study volcanic activity in the Elbrus area, has been functioning for more than 10 years. Results of experimental studies performed at the observatory, located in the deep tunnel, are presented. Special attention is paid to the stability of metrologically significant parameters of precise information-measuring systems, taking into account different nature noises. Technical characteristics of installed geophysical instruments are given, and the principles of their operation are described. Examples of instrumental observations are also presented; for example, tidal deformations reflecting structural features of the geological environment in the area of the Elbrus volcanic edifice and associated with the presence of magmatic structures were investigated. It was shown that diurnal and semidiurnal harmonics observed in the microvariations of temperature can be caused, among other things, by the influence of tidal effects on the convective component of heat–mass transfer. Full article

Fiber optic sensors have gained popularity over the last few decades. This is due to their numerous advantages, such as good metrological parameters, biocompatibility and resistance to magnetic and electric fields and environmental pollution. However, those built from glass fiber have one main disadvantage—they are fragile, meaning they can be easily damaged, even by the presence of vibration. Due to the great progress made by material research recently, it is possible to build such a sensor with polymer fibers instead. Although those fibers have worse transmission parameters compared to telecommunication fibers, they provide the possibility to realize flexible fiber optic sensors. Taking into consideration other advantages of such fibers, including biocompatibility, electromagnetic resistance and even, biodegradation characteristics, as well as there being a variety of materials we can use, it can be seen that those materials are beneficial to produce fiber optic sensors. This paper aims to provide researchers with guidelines on the factors to consider when choosing a material for bent fiber optic sensors, depending on the application. Full article

Single-molecule sequencing technology, a novel method for gene sequencing, utilizes nano-sized materials to detect electrical and fluorescent signals. Compared to traditional Sanger sequencing and next-generation sequencing technologies, it offers significant advantages, including ultra-long read lengths, rapid sequencing, and the absence of amplification steps, making it widely applicable across various fields. By examining the development and components of single-molecule sequencing technology, it becomes clear that its unique characteristics provide new opportunities for advancing metrological traceability. Notably, its direct detection capabilities offer a novel approach to nucleic acid metrology. This paper provides a detailed overview of library construction, signal generation and detection, and data analysis methods in single-molecule sequencing and discusses its implications for nucleic acid metrology. Full article

Optical interferometry has emerged as a cornerstone technology for high-precision length measurement, offering unparalleled accuracy in various scientific and industrial applications. This review provides a comprehensive overview of the latest advancements in optical interferometry, with a focus on grating and laser interferometries. For grating interferometry, systems configurations ranging from single-degree- to multi-degree-of-freedom are introduced. For laser interferometry, different measurement methods are presented and compared according to their respective characteristics, including homodyne, heterodyne, white light interferometry, etc. With the rise of the optical frequency comb, its unique spectral properties have greatly expanded the length measurement capabilities of laser interferometry, achieving an unprecedented leap in both measurement range and accuracy. With regard to discussion on enhancement of measurement precision, special attention is given to periodic nonlinear errors and phase demodulation methods. This review offers insights into current challenges and potential future directions for improving interferometric measurement systems, and also emphasizes the role of innovative technologies in advancing precision metrology technology. Full article

Surface metrology deals with inspecting surfaces and profiles by using contact or non-contact profilometers. In this field, the characterization of the dimensional, morphological, and texture parameters of samples as well as the assessment of metrological characteristics of measuring instruments are key issues. Manufacturers of instruments provide commercial software tools to analyze topography data. There are also freely available tools, including open-source options, that provide a variety of algorithms and methods. The rapid growth of investigations aimed at better understanding the effects of the microscale phenomena requires the improved traceable calibration of samples, the development of new methodologies and measuring techniques, and the specification of new mathematical models and processing techniques. In this work, we present SurfILE, the launch of an open-source Python project that provides various procedures and algorithms for topography analysis. The open-source software presented in this article is intended to be modular, expandable, and customizable. Full article

Faced with increasingly serious environmental problems, scientists have conducted extensive research, among which the importance of air quality prediction is becoming increasingly prominent. This article briefly reviews the utilization of geographic artificial intelligence (AI) in air pollution. Firstly, this paper conducts a literature metrology analysis on the research of geographical AI used in air pollution. That is, 607 documents are retrieved from the Web of Science (WOS) using appropriate keywords, and literature metrology analysis is conducted using Citespace to summarize research hotspots and frontier countries in this field. Among them, China plays a constructive role in the fields of geographic AI and air quality research. The data characteristics of Earth science and the direction of AI utilization in the field of Earth science were proposed. It then quickly expanded to investigate and research air pollution. In addition, based on summarizing the current status of Artificial Neural Network (ANN), Recurrent Neural Network (RNN), and hybrid neural network models in predicting air quality (mainly PM2.5), this article also proposes areas for improvement. Finally, this article proposes prospects for future research in this field. This study aims to summarize the development trends and research hotspots of the utilization of geographic AI in the prediction of air quality, as well as prediction methods, to provide direction for future research. Full article

Due to their advantageous characteristics, shape memory alloys (SMAs) are prominent representatives in smart materials. They can be used in application fields such as soft robotics, biomimetics, and medicine. Within this work, a fiber–elastomer composite with integrated SMA wire is developed and investigated. Bending and torsion occur when the SMA is activated because of the anisotropic structure of the textile. The metrological challenge in characterizing actuators that perform both bending and torsion lies in the large active deformation of the composite and the associated difficulties in fully imaging and analyzing this with optical measurement methods. In this work, a multi-sensor camera system with up to four pairs of cameras connected in parallel is used. The structure to be characterized is recorded from all sides to evaluate the movement in three-dimensional space. The energy input and the time required for an even deflection of the actuator are investigated experimentally. Here, the activation parameters for the practical energy input required for long life with good deflection, i.e., good efficiency, were analyzed. Different parameters and times are considered to minimize the energy input and, thus, to prevent possible overheating and damage to the wire. Thermography is used to evaluate the heating of the SMA wire at different actuation times over a defined time. Full article

The popularity of mobile laser scanning systems as a surveying tool is growing among construction contractors, architects, land surveyors, and urban planners. The user-friendliness and rapid capture of precise and complete data on places and objects make them serious competitors for traditional surveying approaches. Considering the low cost and constantly improving availability of Mobile Laser Scanning (MLS), mainly handheld surveying tools, the measurement possibilities seem unlimited. We conducted a comprehensive investigation into the quality and accuracy of a point cloud generated by a recently marketed low-cost mobile surveying system, the MandEye MLS. The purpose of the study is to conduct exhaustive laboratory tests to determine the actual metrological characteristics of the device. The test facility was the surveying laboratory of the University of Agriculture in Kraków. The results of the MLS measurements (dynamic and static) were juxtaposed with a reference base, a geometric system of reference points in the laboratory, and in relation to a reference point cloud from a higher-class laser scanner: Leica ScanStation P40 TLS. The Authors verified the geometry of the point cloud, technical parameters, and data structure, as well as whether it can be used for surveying and mapping objects by assessing the point cloud density, noise and measurement errors, and detectability of objects in the cloud. Full article