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The Arctic is as a key place to perform environmental measurements given its combination of reduced human activity and increased sensitivity to climate change. The Svalbard archipelago constitutes an invaluable measurement location, due to its ease of access and the presence of the Ny-Ålesund research center. Sensors are usually not designed to sustain prolonged periods of time in demanding environments like the Arctic; therefore, chances of failures, drift, and errors are higher than elsewhere. Maintenance and calibration of these sensors must be rigorous and frequent, to avoid poor-quality data, or even their loss. Within the frame of EURAMET EMRP project “MeteoMet 2”, calibration of the temperature sensors hosted by the Climate Change Tower (CCT), a unique research facility designed to monitor lower-atmosphere profiles of several meteorological quantities, has been performed. The calibration campaign pointed out sensor errors up to 1 °C and corrected the measurements, straightening the skewed temperature profiles. Absolute calibration uncertainties have been evaluated at ∼0.2 °C, less than half of those stated by the manufacturer, while an evaluation of relative uncertainties yielded values of just few 0.01 °C. This experience stimulated the creation of an in-situ calibration facility, to the benefit of the whole scientific community based in Ny-Ålesund.

The small-strain shear modulus of soils and rocks is an important input parameter in geotechnical analyses. Its estimation using the resonant column apparatus relies on accurate knowledge of the rotational inertia of the apparatus’s active end. Due to the complex geometry of the active end, its inertia is typically found from a calibration exercise. In this study a range of aluminium calibration bars and steel masses were used to compare two different calibration exercises presented in the literature. The resulting values of active end inertia are shown to be highly method-dependent. The method of compensating for the drive connection stiffness by finding the apparatus resonant frequency is found to introduce errors at low stiffness. The combined use of calibration bars and masses reduces scatter but yields poor results for stiff bars. An alternative approach to mitigate both of these problems is suggested. Active end inertia is found to be constant using this alternative approach. While effects of base inertia and reaction mass inertia are found to be small for this apparatus, compliance of the drive system is shown to significantly reduce resonant frequencies at high stiffnesses which increases the apparent active end inertia. This reduction in resonant frequency is modelled and used to derive frequency correction factors, which reduce errors in shear modulus to within acceptable limits when using the constant value of active end inertia. This demonstrates the potential for increasing the limit of sample stiffness where sufficient calibration data are available.

Hybrid structured-light measurement technique is used for form measurement of structured composite surfaces. A hybrid structured-light measurement system contains a phase measuring deflectometry (PMD) subsystem and a fringe projection profilometry (FPP) subsystem. Each subsystem measures specular surfaces and rough surfaces based on structured-light reflection and projection principle, respectively. Calibration’s accuracy extremely effects data stitching precision between the subsystems. A novel calibration technique is explored for the hybrid structured-light system to complete reliable measurement accuracy. Calibration algorithms are developed based on designed calibration targets. Information of the calibration procedure are discussed and presented. Effectiveness of the proposed calibration technique has been conducted and verified through experiments by measuring structured composite samples. Experimental results demonstrate that the proposed technique can significantly improve data fusion accuracy of a hybrid structured-light measurement system.

When developing digital twins for buildings, the calibration of simulation models on an hourly basis is essential to maintain the fidelity of the virtual representation and to enable real-time monitoring and analysis in the operational phase. Achieving such a high accuracy in building performance simulations (BPS) calls for novel calibration strategies with enhanced effectiveness. In this regard, this paper outlines a calibration strategy that makes use of hourly measurements to improve the fidelity of energy simulation models. The proposed approach includes a hierarchical structure involving data acquisition and management, setting unknown weather parameters, sensitivity analysis, calibration of fixed parameters, and hourly calibration of dynamic variables. Here, acquired data from the building’s sensor are refined to enable hourly demand calibration, and an accurate weather data file is gathered. Next, sensitivity analysis is conducted to identify the key fixed parameters for the calibration process. Following the calibration of these fixed parameters, the final level involves the calibration of dynamic variables to achieve a robust hourly agreement between simulated and measured data. The developed strategy is implemented in a multi-purpose building located in the Aalto University campus in Finland. The building is simulated as a simplified five-zone model developed in the whole-building simulation software IDA-ICE, including various educational sections, workshops, a shopping center, and a metro station. Sensors and meters are used to measure the hourly indoor air temperature by zone, whereas the calibration aims at minimizing the difference between measured and simulated heating and cooling energy demands. In conclusion, the proposed calibration strategy appears to be successful in facilitating hourly synchronization between simplified simulation models and multi-purpose buildings.

Concrete is a material which undergoes slow increasing deformation while subjected to persistent mechanical stress. This phenomenon is known as creep. In concrete material, creep occurs at all stress levels. Additional deformation of concrete structures at the end of their design working life caused by creep is usually two to three times of the immediate elastic deformation value, but might be even more in some cases. The value is dependent on many parameters, e.g. concrete grade, cement class, ambient environment relative humidity, geometry of the structure (drying surface of concrete in contact with air) and also the age of concrete at the time of loading. According to corresponding European standard, the effects of creep are evaluated using creep coefficient, and should be considered for verification of serviceability limit states, and if significant, also at ultimate limit states. In order to evaluate the creep effects in geometrically more complex structures, numerical finite element (FEM) analyses might be conducted. In commercially available software ANSYS, there is a library of several implicit creep equations, with several input parameters. These parameters need to be calibrated in order to match the assumptions of the creep effects over time in accordance with the corresponding European standard. In this study, calibration process of European standard concrete C35/45 parameters for selected implicit creep equation from ANSYS library is presented. The parameters are calibrated for two different ambient relative humidity (RH) levels, 78.8% and 90%, each for concrete loaded in 28 days (also 90 days for RH 78.8% and 50 days for RH 90%) after its casting, and suitable for finite element analysis of creep effects within the first year after loading of the concrete structure. The calibration process is split into two parts, analytical one conducted in table processor, where approximate estimations of suitable parameter values are determined. The second part consist of the subsequent optimization process in OptiSLang software, where the optimal parameter values are determined in order to achieve the best match between the time dependent Eurocode standard creep coefficient and the creep coefficient based on the results of one solid element uniaxial compression test in ANSYS finite element software. The obtained parameters are then verified on an analysis of a simply-supported concrete beam modelled of solid 3D finite elements. The values of selected creep equation parameters are summarized in the table, and might be used in the subsequent ongoing research.

A case study represented by an assisted living facility in Norway is modeled utilizing physics-based data-driven digital twin (DT) of the indoor thermal spaces with indoor temperature. Autoregressive Distributed Lag (ARDL), Machine Learning (ML), and Non-linear Autoregressive (NARX) models with timeseries and sliding-window cross-validation are compared. Results show that NARX models have the highest accuracy, with a MAPE score of 0.03%. In addition, the sliding-window enhanced the models’ accuracy and reduced the cyclical pattern for the autocorrelated values. The HVAC systems in this study case are representative of those found in Norwegian buildings, making the digital twin calibration applicable to other facilities.

This paper presents an efficient approach to the non-invasive estimation of Systolic Blood Pressure (SBP) using just a single photoplethysmography (PPG) sensor and self-calibration procedure. In this scheme, two features of the measured PPG signal, which are systolic upstroke time (SUT) and PPG inter-beat interval (IBI), are extracted to be used in the estimation model. Here, for each individual, a unique model is self-calibrated in order to provide better accuracy. The experimental results demonstrated the merits and promising potentials for future application of the proposed approach.

The objective of this study was to understand the effect of the choice of backfill constitutive models on the numerical simulation of a geosynthetic reinforced soil-integrated bridge system (GRS-IBS). The #89 material, a crushed angular granite stone, characterized by maximum particle sizes of 9 mm, was used for the reinforced backfill for the retaining wall. Consolidated drained triaxial tests were conducted at confining stresses of 48 kPa, 83 kPa, and 117 kPa. The average friction angle was 42 degrees. Two soil models (the linear-elastic perfectly-plastic and the Hardening Soil) were calibrated using the laboratory test results. The calibrated soil models were then used to model the reinforced backfill material in finite element simulations of the abutment. Results of the calculated vertical stresses at the instrument position showed reasonable agreement with the field measurement. The non-linear model predicted about twice the deformation (lateral displacement and bridge seat settlement) compared to the linear-elastic perfectly plastic model. Settlement results showed maximum values corresponding to 0.22% and 0.45% of the abutment height for linear-elastic perfectly-plastic model and Hardening-Soil model, respectively, which are less than 0.5% limit recommended by US FHWA, while the lateral displacements were 0.22% and 0.44% of the abutment height for linear-elastic perfectly-plastic model and Hardening Soil model, respectively, both less than the 1% limit recommended by the US FHWA.

The Distinct element method (DEM) is a promising approach to model the microscopic behaviour of granular materials, but the capability of the simulations to reproduce the mechanical response of real granular materials depends strongly on the contact model parameters utilized. The present study focuses on the calibration and validation of the rolling resistance linear model parameters for Cuxhaven sand based on the experimental results from triaxial and oedometer tests. A sensitivity analysis was conducted to explore the influence of contact model parameters on the sample preparation and the shear stage of triaxial tests. The influence of parameters like rolling resistance friction coefficient, inter-particle friction coefficient, effective modulus, and normal-to-shear stiffness ratio were investigated. For calibration of the DEM model, the input parameters were selected such that the simulations reproduce the macro mechanical characteristics like dilation angle, peak stress, and stiffness. The calibrated parameters were then validated by simulating a one-dimensional compression test. The results are in good agreement with the experiments, which proves the suitability of the calibrated parameters. In addition, the validated parameters were applied to investigate the mechanical behaviour including the evolution of contact force chains, non-coaxiality of principal stress and strain rate, and sample inhomogeneity during a simple shear test.

This paper presents a novel methodology for calibrating cup anemometers, addressing a critical need in the wind energy sector for accurate and reliable wind speed measurement. Ensuring measurement accuracy through calibration remains a major challenge. In response, a cost-effective alternative methodology is presented that takes advantage of statistical analysis techniques. York linear regression is applied for the estimation of calibration coefficients, a novelty in the context of cup anemometer calibration. The approach overcomes the limitations of traditional procedures reliant on wind tunnel facilities. Experimental validation of the proposed methodology, carried out with wind turbines placed at a height of 10 meters, demonstrates that a reliable calibration can be achieved even in sites with a low wind regime.

In this paper, we report on extensive experiments conducted to evaluate Internet of Things (IoT) sensor performance in monitoring urban air quality. As certified sensors showed a considerably reduced air quality measurement error of 4.3% compared to uncalibrated sensors at 8.5%, our results highlight the crucial function of sensor calibration. The performance of sensors was impacted by environmental factors; higher temperatures produced better accuracy (3.6%), while high humidity levels caused sensors to react more quickly (2.3 seconds). The average air quality index (AQI) recorded by inside sensors was 45, but outside sensors reported an AQI of 60. This indicates that the positioning of the sensors had a substantial influence on the air quality data. Additionally, the methods of data transmission were examined, and it was found that Wi-Fi-transmitting sensors had lower latency (0.6 seconds) and data loss (1.8%) than cellular-transmitting sensors. These results emphasize the significance of environmental factors, sensor placement strategy, sensor calibration, and suitable data transmission techniques in maximizing IoT sensor performance for urban air quality monitoring, ultimately leading to more accurate and dependable air quality assessment.

The aim of the work is to improve the methods of determining the standby time of transit recycling wagons at the sorting station. Systems analysis, analytical, graphical modeling, Ishikawi scheme and methods of comparing the performance of transit and local carriages were used. The reasons for the extra time lost by the wagons at the railway stations were given. Methods of adjusting the stopping time of wagons at the sorting station and their advantages, disadvantages and error rates were studied. The options and time costs of moving the wagon from one loading to the unloading location were analyzed, and the negative factors that cause the wagons to be overstayed at the sorting station were identified. In order to increase the level of performance of the sorting station performance and speed up the delivery of goods, a four-step method of reasonable standardization of the stopping time of wagons was recommended. This method allows you to analyze the time spent on each operation of the wagon on the road, to identify and eliminate inefficient time losses in a timely manner, to identify negative factors and increase the accuracy of standardization methods by 5-10%.

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Copyright of Romantisme is the property of Librairie Armand Colin and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This research investigates the integration of vision-based navigation into the charging procedure of autonomous electric vehicles (AEVs). The study offers a comprehensive examination of the precision of calibration, the ability to identify objects, the navigation capabilities of autonomous cars, and the effectiveness of charging sessions. The visual systems undergo meticulous calibration, which leads to inherent traits that are crucial for accurate perception. Object recognition algorithms have exceptional proficiency in precisely spotting electric vehicles, charging stations, cables, and obstacles, while also exhibiting heightened levels of confidence. The adaptive navigation framework exhibits improved precision, as seen by developments in velocity and steering angle, enabling AEVs to effectively navigate through complex urban scenarios. Examining the data from charging sessions indicates that the integration of vision- based navigation has led to enhanced operational effectiveness of AEVs. This is apparent via the significant reduction in charging duration and the favorable boost in energy output. The cross-parameter analysis reveals the interconnectedness, emphasizing the influence of accurate calibration on the recognition and movement of objects. It showcases a holistic integration of perception, navigation, and charging procedures. The findings have significant implications for the widespread adoption of vision-based navigation, providing a groundbreaking method for seamlessly incorporating autonomous electric vehicles (AEVs) into real-world scenarios. Future research should give priority to enhancing calibration techniques, exploring advanced object detection algorithms, and resolving challenges related to dynamic urban environments. This will serve to validate the agility and reliability of the vision-based navigation architecture. In summary, this research offers valuable insights into the potential impact of vision-based navigation on the process of charging autonomous electric vehicles. Vision-based navigation is essential for the successful operation of AEVs in dynamic urban contexts.

The paper presents the results of a study of the working parts of a screw intended for transportation, drying, and cleaning of raw cotton at high productivity. The problem of the dynamics of a machine unit with a mechanism of camshafts in distribution devices of raw cotton during their storage has been solved and an analytical form of the law of changes in the technological load on the camshafts has been obtained, taking into account the results of experimental studies. An oscillogram of the camshaft at idle speed was experimentally obtained. Using the calibration of the measuring channel and the calibration coefficient was determined from the calibration graph, also used the fast Fourier transform method and converted the resulting amplitude value into current units of “ampere”, changes in the power of the electric motor of the shaft, cam, and screw for idle speed were obtained in the form of a graph and the value was determined torque of the electric motor equal to Me=0.91 N·m.

Data-driven models are gaining traction in Building Energy Simulation, driven by the increasing role of smart metering and control in buildings. This paper aims to enhance the knowledge in this sector by introducing a practical method to analyse heating consumption. The methodology involves the analysis of hourly total heating demand and outdoor temperature measurements to create and calibrate Energy Signature Curves. Importantly, the building Energy Signature Curve is calibrated independently for each daily hour, resulting in a subset of 24 data-driven models. After calibration, a disaggregation algorithm is proposed to distinguish space heating from domestic hot water usage. The method also evaluates the building’s thermal inertia, examining the correlation between the hourly global energy consumption and the outdoor air temperature moving average. It also presents a methodology for improving the DHW heat consumption model. The methodology is applied to a case study of 51 buildings in Tartu, Estonia, with complete yearly demand measurements from the district heating operator. Thanks to the hourly calibration approach, R2 is 0.05 higher on average than the yearly Energy Signature Curve approach. The difference between estimated and measured annual energy consumption is 8% on average, demonstrating the practicality and effectiveness of the proposed method.

Copyright of Recherche et Applications en Marketing (Sage Publications Inc.) is the property of Sage Publications Inc. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Pulsed eddy currents can be used to determine the thickness of a conducting plate. This method is extended to enable the measurement of the plate thickness and its material properties simultaneously. The need for a calibration of the material properties of a conducting plate to enable the measurement of its thickness has been removed. The method relies on a suitable geometry with well known dimensions and suitable hardware to create a current pulse and measure a transient magnetic induction. For an optimal performance, the design depends on the thickness range that should be accessible.

Copyright of Revue Française de Géotechnique is the property of EDP Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Annales Françaises de Médecine d'Urgence is the property of John Libbey Eurotext Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revue Archéologique de Picardie is the property of Revue Archeologique de Picardie and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revue Archéologique de Picardie is the property of Revue Archeologique de Picardie and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

RÉSUMÉLe projet HOMONIM phase 3 est mené par MétéoFrance et le Shom sous la maîtrise d’ouvrage de la Direction Générale de la Prévention des Risques (DGPR). Il vise à améliorer les capacités opérationnelles de modélisation des niveaux marins et des vagues à la côte pour aider la gestion du risque de submersion marine. Les principaux travaux de R&D en cours et à venir dans le projet HOMONIM3 sont abordés dans cet article : configuration de façade Manche – Atlantique du nouveau modèle de niveau marin TOLOSASW, calibration de la prévision d’ensemble (PE) de surcotes, mise en place d’une PE des vagues en côtier, modélisation couplée vagues/niveaux/courants à très haute résolution, pour le littoral Nord-Aquitain, et la modélisation non hydrostatique. Ces résultats sont susceptibles de servir aux modèles de prévision des inondations à proximité des estuaires ou des fleuves près de leur embouchure, en leur fournissant, sur leur frontière maritime, une condition limite plus réaliste, et cohérente avec les prévisions utilisées pour le dispositif de la Vigilance Vagues-Submersion (VVS), ainsi qu’une information, pour un jour donné, sur la prévisibilité des modèles ou sur l’existence de scénarios océaniques alternatifs.

Automatic Ultrasonic Testing (AUT) systems for pipeline girth weld inspections are usually subjected to a qualification process. This process consists of assessment of performance capabilities including detection, sizing, temperature range and repeatability. One of the most demanding qualification programmes is described in DNV ST-F101 Appendix E [1]. With the introduction of the AUT module in the 2023 edition of CIVA simulation software, the incorporation of metamodeling allows users to predict detection reliability via probability of detection (POD) and sizing accuracy of the zonal discrimination method (ZDM) using amplitude apportioning. Part 1 of this project demonstrated the ability of CIVA to simulate the calibration block and strip chart output. In Part 2 we illustrate the techniques that can be used to predict POD and sizing accuracy as might be done in a system qualification. Results compare well to field data.

The Total Focusing Method (TFM) technique is an advanced Non-Destructive Testing (NDT) Ultrasonic Testing (UT) technique. It is usually used together with special acquisition configurations such as Full Matrix Capture (FMC) or Plane Wave Imaging (PWI) and can supply synthetic post-processing results based on a quantity of ultrasonic signals. It is believed that it will accelerate the UT technique revolution toward the artificial intelligence era. Compared to the conventional UT technique, or even advanced UT techniques, such like Time of Flight Diffraction (TOFD) and Phased Array (PA) techniques, this advanced UT technique is well known for its easy-to-interpret and high-resolution representative images. For these reasons, it is used more and more in the flaw sizing and characterization assessment. Following the publication of the standard ISO 23864, TFM technique become a member among all standardized weld inspection techniques. This article presents some related study results toward a code-compliant weld inspection regarding the related standards, dealing especially with the sensitivity calibration which is a key point for the applicability of amplitude-based acceptance criteria.

Standard calibration blocks to assess beam paths and configure data displays using ultrasonic instruments use low carbon steel with isotropic acoustic properties. However, industry is trending towards the use of high tensile steels where the acoustic properties are anisotropic. When an ultrasonic system, calibrated on an isotropic steel reference block, is used on anisotropic steels, the beam can be bent, skewed and attenuated so that the reference setup is rendered useless. CIVA simulation software can be used to aid in understanding the effects on the data displays. As well, CIVA can help to demonstrate the degree of change that can occur when the acoustic velocities are established for the fast and slow shear modes in an anisotropic steel.

The main standards relating to AUT (Automated Ultrasonic Testing) using zonal discrimination have long had requirements to incorporate separate channels dedicated to detecting volumetric flaws. However, none of the standards specify how the beams are to be configured. The instructions are quite generic indicating that the channels are to ensure the complete volumetric examination of the weld through-thickness. Scattering flat bottom hole targets in a calibration block such that they evenly distribute in the volume is not a guarantee that the target placement provides the required complete volume coverage. This paper illustrates how the Coverage component of the CIVA AUT module helps to identify the best placement of volumetric targets in an AUT Zonal Discrimination procedure and prevents target redundancy.