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Laboratory calibration methods are time-consuming and require accurate devices to find the error coefficients of the low-cost microelectromechanical system (MEMS) accelerometer. Besides, low-cost MEMS sensors highly depend on temperature because of their silicon property and the effect of temperature on error coefficients should also be considered for compensation. This paper aims to present a field calibration method in which the accelerometer is placed in different positions without any accurate equipment in a few minutes and its temperature is changed by a simple device like a hairdryer.

In this paper, a non-linear cost function is defined based on this rule that the magnitude of the acceleration measured by the accelerometer in static mode is equal to the gravity plus error factors. Also, the dependency of error coefficients of the accelerometer is presented as a second-order polynomial in this cost function. By minimizing the cost function, the accelerometer error coefficients include bias, scale factor and non-orthogonality and their temperature dependency are obtained simultaneously.

Simulation results in MATLAB and empirical results of a MPU6050 accelerometer verify the good performance of the proposed calibration method.

Finding a fast and simple field calibration method to calibrate a low-cost MEMS accelerometer and compensate for the temperature dependency without using accurate laboratory equipment can help a wide range of industries that use advanced and expensive sensors or use expensive laboratory equipment to calibrate their sensors, to decrease their costs.

The relation between the output of the fluxset sensor and the magnetic field is established by the numerical and experimental investigation of an ECT set‐up. A fast calculation method has been developed for obtaining the magnetic field generated by the interaction of the probe and the crack in a finite plate by superimposing the results obtained by the analysis of a finite plate without a crack and an infinite plate with a crack. The calculations are made by FEM and boundary integral methods, respectively. The relationship between the measured output and the magnetic field is obtained by calculating the calibration factors giving the best fit of the two sets of data. Based on the results, a numerical tool is developed for the quantitative evaluation of magnetic field sensors applied to the measurement of spatially inhomogeneous fields.

This paper aims to determine and evaluate the calibration curve for low-cost electronic sensors in soils from a reclaimed and degraded area in the Brazilian semiarid region.

The probes were made, programmed and inserted in soil previously conditioned in polyethylene cylinders. The sets “cylinder + probe + soil” were subjected to saturation for a period of 24 h and, subsequently, gravitational drainage at room temperature and daily weighings were performed. When the set reached constant weight, the samples were taken to dry in an oven at 105°C to determine the dry mass and later, determine the gravimetric moisture and convert it into volumetric. The volumetric moistures obtained were related to measured frequency variations and the adjustments were analyzed by regression, which was subjected to analysis of variance (p = 0.05), and related by a third-degree polynomial equation whose quality of the fit was verified with coefficient of determination (R²).

The obtained moistures were related to the estimated moistures and evaluated by the root-mean-square error and straight 1:1. The results demonstrate that the sensors are not accurate for moistures in saturation, but representative and statistically acceptable results for moistures up to field capacity.

This paper has not been published before in its current, or similar form.

Sediment measurement is usually accessible on a periodic or distinct basis. The measurement of sediment (suspended and bedload), especially in the field, is vital in keeping essential data of sediment transport and deposition. Various techniques for measuring sediment have been used over time each with its merits and demerits. The techniques discussed in this paper for suspended sediment include bottle, acoustic, pump, laser diffraction, nuclear and optical. Other techniques for bedload measurement are; River bedload trap (RBT), CSU/FU bedload trap, Helley–Smith, Polish Hydrological Services (PIHM) device, pit and trough, vortex tube, radioactive traces and bedload–surrogate technologies. However, the choice of technique depends on multiple factors ranging from budget constraint, availability of equipment, manpower and data requirement. The purpose of this paper is to present valuable information on selected techniques used in sediment measurement, to aid researchers/practitioners in the choice of sediment measurement technique.

This paper presents a general review of selected field techniques used in sediment measurement (suspended and bedload). Each techniques mode of operation, merits and demerits are discussed.

This paper highlights that each technique has its peculiar merits and demerits. However, two techniques are generally preferred over others; the bottle sampling and the Helley–Smith sampler for measuring suspended and bedload sediment. This is because the applicability of these techniques is quite widespread and time-tested.

This review paper provides an in-depth description and comparison of selected existing field sediment measurement techniques. The objective is to ease decision-making about the choice of technique, as well as to identify the suitability and applicability of the chosen technique.

Antenna and electric field probe calibration requires precise positioning and movement throughout a known RF field. Measurements are usually made in an anechoic chamber. A robotic six‐axis antenna positioner was needed that would work in this environment at NIST. Discusses NIST’s vendor‐selection process for the new positioner and how the positioner has enhanced their capabilities. Also chronicles the design, technical challenges and manufacture of the positioner by Mek‐A‐Nize Engineering & Robotics, Inc., the vendor selected by NIST to provide the turnkey robotic antenna positioner.

This main purpose of this study is to summarize the experience at the Construction Technology and Management Center (CTMC) to develop a Digitalizing Construction Monitoring (DCM) system by integrating 3DAutoCAD drawings and digital images. The objective of this paper is to propose a framework model for the DCM system and discuss in detail the steps involved for developing and calculating the 3D coordinate values from 2D digital images.

As digital images are one of the major sources of information from site, the process of measuring the project progress from images is quite challenging. This study used Photogrammetry techniques to extract the information from digital images, which can be concisely defined as the science of calculating 3D object coordinates from images, with PhotoModeler pro‐version software. Issues pertaining to the quality of the 3D model derived from 2D digital images are also discussed.

A framework model for DCM was proposed and different phases were discussed. A pilot case study on Larkin Mosque Car Parking Project was conducted to check the validity of using Photogrammetry techniques to extract 3D coordinate values by using PhotoModeler Software. Preliminary results show that significant control has been achieved to extract 3D coordinate values from 2D digital images, which and can be integrated into the digitalized system to automate the construction project monitoring process.

The techniques discussed in this paper are used for monitoring the project progress systematically. The results of this study will be incorporated to develop a fully automated project progress monitoring system, which can be updated automatically as the project progresses automatically.

DEPLOY is a successful technology demonstration project showing how state of the art technology can be implemented to achieve, continuous, real‐time monitoring of a river catchment.

The DEPLOY system is a wide area network of monitoring stations delivering data in near real‐time. The demonstration sites chosen are based in the River Lee, which flows through Ireland's second largest city, Cork. The sites include monitoring stations in five zones considered typical of significant river systems and demonstrate the versatility of the technology available. Data were collected from stations at pre‐programmed intervals and transmitted to the DEPLOY servers either by short range ISM band radio or directly via the GSM GPRS network. The data were then processed and made available in a controlled manner at www.deploy.ie Findings – The project demonstrates the capability of multi‐sensor systems to remotely monitor temporal and spatial variations in water quality, through the identification of short‐term events. A system like DEPLOY could be used as a decision support tool by regulatory bodies in managing our aquatic environment with the potential to cut overall monitoring costs and provide better coverage representing long‐term trends in fluctuations of pollutant concentrations.

The demonstration of a truly heterogeneous water quality monitoring networked system was one of the first of its kind in Ireland. Based on the collected data DEPLOY can provide recommendations for water quality monitoring systems from various perspectives, technical, operational and strategic.

In spite of the vehicle, magnetic field interference can be reduced by some measures and techniques in ammunition design and manufacturing stage, the corruption of the vehicle magnetic field can still reach hundreds to thousands of nanoteslas. Besides, the magnetic field that the ferromagnetic materials generate in response to the strong magnetic field in the vicinity of the body. So, a real-time and accurate vehicle magnetic field calibration method is needed to improve the real-time measurement accuracy of the geomagnetic field for spinning projectiles.

Unlike the past two-step calibration method, the algorithm uses a linear model to calibrate the magnetic measurement error in real-time. In the method, the elliptical model of magnetometer measurement is established to convert the coefficients of hard and soft iron errors into the parameters of the elliptic equation. Then, the parameters are estimated by recursive least square estimator in real-time. Finally, the initial conditions for the estimator are established using prior knowledge method or static calibration method.

Studies show the proposed algorithm has remarkable estimation accuracy and robustness and it realizes calibration the magnetic measurement error in real-time. A turntable experiments indicate that the post-calibration residuals approximate the measurement noise of the magnetometer and the roll accuracy is better than 1°. The algorithm is restricted to biaxial magnetometers’ calibration in real-time as expressed in this paper. It, however, should be possible to broaden this method’s applicability to triaxial magnetometers' calibration in real-time.

Unlike the past two-step calibration method, the algorithm uses a linear model to calibrate the magnetic measurement error in real-time and the calculation is small. Besides, it does not take up storage space. The proposed algorithm has remarkable estimation accuracy and robustness and it realizes calibration the magnetic measurement error in real time. The algorithm is restricted to biaxial magnetometers’ calibration in real-time as expressed in this paper. It, however, should be possible to broaden this method’s applicability to triaxial magnetometers’ calibration in real-time.

The purpose of the present paper is to propose a full model‐based method for distance‐mapping calibration for the non‐SVP (non‐single viewpoint) catadioptric camera of the soccer robot. The method should be easy to operate, efficient, accurate, and scalable to fit larger field sizes.

The distance‐mapping model was first constructed based on the imaging principle. The authors then calibrated the internal parameters using the mirror boundary and used the mirror center to choose the correct pose from two possible solutions. The authors then proposed a three‐point method based on a unique solution case of the non‐SVP P3P (perspective‐three‐point) problem to solve the external parameters. Lastly, they built the distance mapping by back‐projection.

The simulation experimental results have shown that the authors' method is very accurate even when there is severe misalignment between the mirror and the camera and that all calibration operations, except the calibration of a standard camera, can be completed in 1 min. The result of the comparison with the traditional calibration method shows that the authors' method is superior to the traditional method in terms of accuracy and efficiency.

The proposed calibration method is scalable to larger fields because it only uses the boundary of the mirror and three feature points on the field, and does not need additional calibration objects. Additionally, an automatic calibration method that can be used during the game can be easily developed based on this method. Moreover, the proposed mirror‐pose‐selection method and a unique solution to the non‐SVP P3P problem are especially useful for a non‐SVP catadioptric camera.

The purpose of this paper is to provide a comprehensive review of a non-contact full-field optical measurement technique known as digital image correlation (DIC).

The approach of this review paper is to introduce the research pertaining to DIC. It comprehensively covers crucial facets including its principles, historical development, core challenges, current research status and practical applications. Additionally, it delves into unresolved issues and outlines future research objectives.

The findings of this review encompass essential aspects of DIC, including core issues like the subpixel registration algorithm, camera calibration, measurement of surface deformation in 3D complex structures and applications in ultra-high-temperature settings. Additionally, the review presents the prevailing strategies for addressing these challenges, the most recent advancements in DIC applications across quasi-static, dynamic, ultra-high-temperature, large-scale and micro-scale engineering domains, along with key directions for future research endeavors.

This review holds a substantial value as it furnishes a comprehensive and in-depth introduction to DIC, while also spotlighting its prospective applications.