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Travelling waves in circuit chains are studied to measure continuous dispersion. A lock‐in frequency meter (LIF) is suitable for precisely determining k for each set ω$\omega $ of waves in finite alternate LC chains, where LIF has been proven to be more accurate than the fast Fourier transform. In addition to the ω$\omega $–k measurement, the wave impedance spectrum of the travelling wave can be measured simultaneously, for investigating the dispersion and splitting of pulse propagation. The measured dispersion is validated to be consistent with the derived theoretical equations. The result provides an independent way to precisely obtain dynamical system properties for chains composed of non‐ideal components, such as resistors for researching non‐Hermitian behaviour under dissipation. Systematical mapping of relative deviation dependence of wave dispersion measurement with LIF on different chain length and component variation is studied, indicating boundaries of 1%, 0.1%, and 0.01% precision for guidance of experiments. [ABSTRACT FROM AUTHOR]

This study presents the development of a measurement acquisition system for force measurement and temperature cutting using virtual instrumentation. The developed measurement chain enables very efficient, accurate, reliable and fast data collection during the measurement process. The presented acquisition system was developed for the face milling process, but its application is also intended for turning or grinding processes. Emphasis is placed on the creation and description of a software solution in order to manage hardware measuring sensors. Two versions of the virtual instrument are presented. The first one is based on the measurement of three components of cutting forces, obtained by means of a piezoelectric dynamometer. And the second one is upgraded with another channel that represents the temperature change record obtained by the thermocouple. At the end, the experimental results for face milling are shown. A graphical diagram obtained based on some of the data generated by the innovative measuring chain applied to the milling process is presented. [ABSTRACT FROM AUTHOR]

The unbalanced operation of the three-phase grid has a large number of negative consequences. The solution to this problem of unbalance, problem that appears whenever an unbalanced or single-phase load is connected to the network can be based either on conversion, or on compensation. Compensation based methods are capable of compensating not only the unbalanced operations, but also the non-sinusoidal and reactive operations. Former papers of the authors study the compensations methods. In this paper there is developed a LabView virtual instrument capable to calculate the unbalance factor of the grid and to control the active power filter used for compensation. The developed virtual instrument enables the activation of the compensation depending on the values of the measured and calculated unbalance factor. The method compensates the nonsinusoidal, reactive and unbalanced operations of the three-phase grid. Measurements prove the instrument’s efficient operation and the method’s viability. [ABSTRACT FROM AUTHOR]

This article presents a comprehensive system for testing and verifying shunt active power filter control methods. The aim of this experimental platform is to provide tools to a user to objectively compare the individual control methods. The functionality of the system was verified on a hardware platform using least mean squares and recursive least squares algorithms. In the experiments, an average relative suppression of the total harmonic distortion of 22% was achieved. This article describes the principle of the shunt active power filter, the used experimental platform of the controlled current injection source, its control system based on virtual instrumentation and control software and ends with experimental verification. The discussion of the paper outlines the extension of the experimental platform with the cRIO RTOS control system to reduce the latency of reference current generation and further planned research including motivation. [ABSTRACT FROM AUTHOR]

In the fields of metallurgy, mining, coking, rubber, ceramics, cement, grain, friction materials, and other industries, the batching process is crucial. It's sometimes referred to as the ''throat'' of industrial firms' manufacturing processes. It eloquently contrasts its significance throughout the entire production process. The first objective of the paper is to explain the workings of a dynamic control system for the process of automatic batch weighing and ingredient discharge. The control system is designed to provide maximum flexibility. It incorporates dual sensory mechanisms to more accurately monitor the density and amount of ingredients in a particular container and aid in the precise mixing of different ingredients as per the formula. Innumerable formulas can be added to the system. The second object of the paper is to compare the effects of incorporating NI LabVIEW in designing the control system. We have reviewed NI LabVIEW software with SCADA software on variables such as load handling capacity, computational ability, processing speed, flexibility of programming, and ease of use for the system and the users. The PLCs and process control systems (PCSs) are used to automate the production process. There are integrated system solutions available today for the automation hardware of PLCs and process control systems. It has been demonstrated that the system is inexpensive, highly reliable, and simple to use. It significantly reduces labour intensity and eliminates health risks from dust in the production line for friction materials. It is worthwhile to encourage use across relevant industries. The Auger mechanism is used for the precise discharge of ingredients.

For monitoring the online jet characteristics and improving the corresponding diagnostic accuracy, caused by the complex working environment of arc plasma generation systems, an online diagnostic method of arc plasma jet characteristics based on wavelet transform and linear regression theory was proposed. The wavelet denoising to improve the accuracy of plasma jet characteristics and the linear regression theory to predict the plasma arc voltage characteristics have been discussed. Hence, a comprehensive online diagnostic system of plasma jet characteristics has been designed by integrating the proposed method with LabVIEW virtual instrument technology. To verify the effectiveness of the online diagnostic method and system, the corresponding experiments have been conducted by using a homemade plasma generation system with specified working parameters. Sequence, the experimental results have been analyzed and discussed. The experimental results show that: (1) the proposed online diagnostic method based on wavelet transform and linear regression theory could effectively improve the accuracy and predict the jet characteristics of plasma jets; (2) the online jet characteristics of thermal plasma jet could be monitored by using the corresponding diagnostic system. [ABSTRACT FROM AUTHOR]

This paper focuses on the development and evaluation of an automated system for the deposition of ZnO thin films with suitable properties to be used in solar cells, using the plasma assisted reactive evaporation (PARE) method. A description is made of both the electronic system developed and the Zn evaporation source implemented with a novel design based on the effusion cell concept. This development made it possible to significantly improve both the low reproducibility of the optoelectric properties and the inhomogeneity of the thickness of the ZnO films that were deposited using a previous version of the PARE system developed.The improvement of thickness homogeneity and the applicability of the ZnO thin films for use in solar cells was verified through measurements of the thickness, spectral transmittance and electrical resistivity of samples deposited on 5 × 4 cm2 glass substrates. By optimizing the preparation parameters, it was possible to deposit thin ZnO films with improved thickness homogeneity, characterized by having resistivities varying between 9.5 × 10−4 Ωcm (n+-ZnO) and 2 × 104 Ωcm (i-ZnO) and transmittances greater than 85% (in the visible region). The structural, optical and morphological properties of the ZnO films were studied by different techniques.

A planetary gearbox is more complex in structure and motion than a gearbox with a fixed shaft, making it difficult to monitor and make a fault diagnosis in practice. Components must be frequently inspected to avoid excessive wear, but there is no simple way to directly measure wear. The most direct method is to log vibration and temperature signals using external sensors. Wireless sensors offer more space advantages than a wired one, so this study developed a measurement system that features a three-axis MEMS accelerometer, temperature sensing and wireless modules that are integrated into a planetary gearbox. Along with the system, a virtual instrument (VI) utilizing graphics programming language LabVIEW was developed to acquire and display data time and frequency domains to detect the gear's faults. To determine the root cause of vibrations in a planetary gearbox, determine the vibration signal model of amplitude modulation (AM) and frequency modulation (FM) due to gear damage and derive the characteristic frequencies of vibrations for a planetary gearbox, the characteristic frequencies and AMFM modulation were summarized in closed form. Different degrees of each gear damage were then detected in the planetary gearbox. The vibration signal model was validated by experiments to indicate the sideband around the gear meshing frequency and its feasibility for fault diagnosis of a planetary gearbox with the wireless embedded sensor. [ABSTRACT FROM AUTHOR]

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This article presents a comprehensive system for testing and verifying shunt active power filter control methods. The aim of this experimental platform is to provide tools to a user to objectively compare the individual control methods. The functionality of the system was verified on a hardware platform using least mean squares and recursive least squares algorithms. In the experiments, an average relative suppression of the total harmonic distortion of 22% was achieved. This article describes the principle of the shunt active power filter, the used experimental platform of the controlled current injection source, its control system based on virtual instrumentation and control software and ends with experimental verification. The discussion of the paper outlines the extension of the experimental platform with the cRIO RTOS control system to reduce the latency of reference current generation and further planned research including motivation.

In online education, carrying out practical work remotely is a problem that can be successfully solved by using virtual instrumentation. Starting from a survey on the degree of acceptance of the online learning, we try to improve the coverage of practical hours by implementing a virtual laboratory made in the LabVIEW environment. [ABSTRACT FROM AUTHOR]

A virtual instrument, calorimetric etching solution analyzer based on LabVIEW 2010 platform was developed, characterized and validated for the on-line automated H2O2 concentration monitoring in SC-1 etching solution applied in the semiconductor industry. The virtual instrument completely controls all analyzer functions including sampling, analytical response measurement, digital data processing and H2O2 concentration calculation as well as the instrument calibration and real time concentration correction by fresh solution addition to the etching machine. The hardware, the software, the user interface and the instrument functioning are presented and discussed with the analytical characterization and validation by industrial sample analysis in comparison with a standard permanganate method. [ABSTRACT FROM AUTHOR]

The quartz crystal microbalance with dissipation (QCM-D) represented a substantial breakthrough in the use of the QCM sensor in diverse applications ranging from environmental monitoring to biomedical diagnostics. To obtain the required selectivity and sensitivity of a volatile organic compounds (VOC) sensor, it is necessary to coat the QCM sensor with a sensing film. As the QCM sensor is coated with the sensing film, an increase in the dissipation factor occurs, resulting in a shorter and shorter ring-down time. This decrease in ring-down time makes it difficult to implement the QCM-D method in an economical and portable configuration from the perspective of large-scale applications. To compensate for this effect, a regenerative method is proposed by which the damping effect produced by the sensing film is eliminated. In this sense, a regenerative circuit as an extension to a virtual instrument is proposed to validate the experimental method. The simulation of the ring-down time for the QCM sensor in the air considering the effect of the added sensing film, followed by the basic theoretical concepts of the regenerative method and the experimental results obtained, are analyzed in detail in this paper. [ABSTRACT FROM AUTHOR]

The usage of virtual instruments (VIs) to analyze measurements and calculate uncertainties is increasing. Well-known examples are virtual coordinate measurement machines (VCMMs) which are often used and even commercially offered to assess measurement uncertainties of CMMs. A more recent usage of the VI concept is posed by the modeling of scatterometers. These VIs can be used to assess the measurement uncertainty after the measurement has been performed based on the real measurement data or prior to the measurement to predict the measurement uncertainty using a type of simulated measurement data. The research question addressed in this paper is to assess if this predicted uncertainty will be similar in magnitude to the calculated uncertainty based on the measurement data. It turns out that this is not necessarily the case. The main observation of this paper was that the uncertainty predicted by a VI can be highly sensitive to the chosen way of operating the VI. To amend this situation, a simple procedure was proposed that can be used prior to performing the real measurement and that is believed to produce a conservative prediction of the measurement uncertainty in most cases. This was verified in a case study involving the measurement of the asphericity of an imperfect sphere using a CMM, with the uncertainty calculated by means of a VCMM. [ABSTRACT FROM AUTHOR]

An Internet-based system for testing and analyzing psychological and physiological responses during creative learning was developed using virtual instruments based on microcomputer interfaces and network communication technologies. The system can be used to study and evaluate innovative learning processes and performance at the psychological and physiological levels. This paper presents the design, implementation, and application of the system. [ABSTRACT FROM AUTHOR]

An Internet-based system for testing and analyzing psychological and physiological responses during creative learning was developed using virtual instruments based on microcomputer interfaces and network communication technologies. The system can be used to study and evaluate innovative learning processes and performance at the psychological and physiological levels. This paper presents the design, implementation, and application of the system.

A planetary gearbox is more complex in structure and motion than a gearbox with a fixed shaft, making it difficult to monitor and make a fault diagnosis in practice. Components must be frequently inspected to avoid excessive wear, but there is no simple way to directly measure wear. The most direct method is to log vibration and temperature signals using external sensors. Wireless sensors offer more space advantages than a wired one, so this study developed a measurement system that features a three-axis MEMS accelerometer, temperature sensing and wireless modules that are integrated into a planetary gearbox. Along with the system, a virtual instrument (VI) utilizing graphics programming language LabVIEW was developed to acquire and display data time and frequency domains to detect the gear’s faults. To determine the root cause of vibrations in a planetary gearbox, determine the vibration signal model of amplitude modulation (AM) and frequency modulation (FM) due to gear damage and derive the characteristic frequencies of vibrations for a planetary gearbox, the characteristic frequencies and AMFM modulation were summarized in closed form. Different degrees of each gear damage were then detected in the planetary gearbox. The vibration signal model was validated by experiments to indicate the sideband around the gear meshing frequency and its feasibility for fault diagnosis of a planetary gearbox with the wireless embedded sensor.

Technological evolution has allowed impedance analysis to become a versatile and efficient method for the precise measurement of the equivalent electrical parameters of the quartz crystal microbalance (QCM). By measuring the dissipation factor, or another equivalent electrical parameter, the QCM sensor provides access to the sample mass per unit area and its physical parameters, thus ensuring a detailed analysis. This paper aims to demonstrate the benefits of advanced impedance spectroscopy concerning the Butterworth–van Dyke (BVD) model for QCM sensors immersed with an electrode in a liquid medium. The support instrument in this study is a fast and accurate software-defined virtual impedance analyzer (VIA) with real-time computing capabilities of the QCM sensor's electric model. Advanced software methods of self-calibration, real-time compensation, innovative post-compensation, and simultaneous calculation by several methods are the experimental resources of the results presented in this paper. The experimental results validate the theoretical concepts and demonstrate both the capabilities of VIA as an instrument and the significant improvements brought by the advanced software methods of impedance spectroscopy analysis related to the BVD model. [ABSTRACT FROM AUTHOR]

This paper presents the results of research framed in sustainable development goal number 6 called Clean water and Sanitation. Through research, it was found that water quality can be determined by measuring its turbidity, research objective was to design a measurement system which would allow to measure turbidity level in different samples using digital image analysis. This work was divided into different phases, starting with an image capture of the samples illuminated with LED light sources of different colors and different angles. Second instance, the processing and analysis of the captured images was carried out, and finally, with data obtained, mathematical model was obtained, it would allow the system to be designed. Study allowed observing the qualities and LED light depending behavior on its wave frequency and location from which the photographic shot is taken. Results obtained allowed finding a correlation between 0.95 and 1.0. Likewise, it was found that blue colored LED light with capture angle from the side offered the best correlation, therefore the most optimal option for the measurement was determined. [ABSTRACT FROM AUTHOR]

The quartz crystal microbalance with dissipation (QCM-D) represented a substantial breakthrough in the use of the QCM sensor in diverse applications ranging from environmental monitoring to biomedical diagnostics. To obtain the required selectivity and sensitivity of a volatile organic compounds (VOC) sensor, it is necessary to coat the QCM sensor with a sensing film. As the QCM sensor is coated with the sensing film, an increase in the dissipation factor occurs, resulting in a shorter and shorter ring-down time. This decrease in ring-down time makes it difficult to implement the QCM-D method in an economical and portable configuration from the perspective of large-scale applications. To compensate for this effect, a regenerative method is proposed by which the damping effect produced by the sensing film is eliminated. In this sense, a regenerative circuit as an extension to a virtual instrument is proposed to validate the experimental method. The simulation of the ring-down time for the QCM sensor in the air considering the effect of the added sensing film, followed by the basic theoretical concepts of the regenerative method and the experimental results obtained, are analyzed in detail in this paper.

This paper presents an experimental investigation of a commercial shape memory alloy strip consisting of nickel and titanium (NiTi SMA), which correlates the thermal properties (phase transitions) with the electrical and mechanical properties of the material, allowing to be used for control applications in engineering. The bending performances of the SMA strip at different values of the activation electric current, during heating process, are also investigated. By using the differential scanning calorimetry (DSC) experiments, the thermal characteristics of the SMA strip were identified. The results of this thermal analysis were the basis for determining the equilibrium temperature, entropy and force developed by the SMA strip during the phase transformation. For the study of the SMA strip, the authors have developed an experimental platform, which uses a portable reconfigurable I/O (RIO) device and LabVIEW graphical programming environment for the measurement, testing and rapid control of parameters, and a piezo-film sensor for controlling of SMA strip movement. The real-time measurements and acquired waveforms are displayed on a PC screen, and the data associated with these waveforms are stored for later use, i.e. for applications in safety engineering like the fire extinguishing control, where very short response/activation times are required. [ABSTRACT FROM AUTHOR]

An implementation of a two-stage piece-wise linearization method for reduction of the thermocouple approximation error is presented in the paper. First, the whole thermocouple measurement chain of a transducer is described, and possible error is analysed to define the required level of accuracy for linearization of the transfer characteristics. Evaluation of linearization functions and analysis of approximation errors are performed by the virtual instrumentation software package LabVIEW. The method is appropriate for thermocouples and other sensors where nonlinearity varies a lot over the range of input values. The basic principle of this method is to first transform the abscissa of the transfer function by a linear segment look-up table in such a way that significantly nonlinear parts of the input range are expanded before a standard piece-wise linearization. In this way, applying equal-segment linearization two times has a similar effect to non-equal-segment linearization. For a given examples of the thermocouple transfer functions, the suggested method provides significantly better reduction of the approximation error, than the standard segment linearization, with equal memory consumption for look-up tables. The simple software implementation of this two-stage linearization method allows it to be applied in low calculation power microcontroller measurement transducers, as a replacement of the standard piece-wise linear approximation method. [ABSTRACT FROM AUTHOR]

Technological evolution has allowed impedance analysis to become a versatile and efficient method for the precise measurement of the equivalent electrical parameters of the quartz crystal microbalance (QCM). By measuring the dissipation factor, or another equivalent electrical parameter, the QCM sensor provides access to the sample mass per unit area and its physical parameters, thus ensuring a detailed analysis. This paper aims to demonstrate the benefits of advanced impedance spectroscopy concerning the Butterworth–van Dyke (BVD) model for QCM sensors immersed with an electrode in a liquid medium. The support instrument in this study is a fast and accurate software-defined virtual impedance analyzer (VIA) with real-time computing capabilities of the QCM sensor’s electric model. Advanced software methods of self-calibration, real-time compensation, innovative post-compensation, and simultaneous calculation by several methods are the experimental resources of the results presented in this paper. The experimental results validate the theoretical concepts and demonstrate both the capabilities of VIA as an instrument and the significant improvements brought by the advanced software methods of impedance spectroscopy analysis related to the BVD model.

The impedance quartz crystal microbalance (QCMI) is a versatile and simple method for making accurate measurements of the QCM sensor electrical parameters. The QCM sensor provides access to the physical parameters of the sample beyond the mass per unit area by measuring the dissipation factor, or another equivalent, ensuring a detailed analysis of the surface. By establishing a cooperative relationship between custom software and modular configurable hardware we obtain a user-defined measurement system that is called a virtual instrument. This paper aims primarily to improve and adapt existing concepts to new electronics technologies to obtain a fast and accurate virtual impedance analyzer (VIA). The second is the implementation of a VIA by software to cover a wide range of measurements for the impedance of the QCM sensor, followed by the calculation of the value of lumped electrical elements in real time. A method for software compensation of the parallel and stray capacitance is also described. The development of a compact VIA with a decent measurement rate (192 frequency points per second) aims, in the next development steps, to create an accurate impedance analyzer for QCM sensors. The experimental results show the good working capacity of QCMI based on VIA.

Electric vehicle (EV) technology proposed itself as a great solution for the predictable shortage in traditional energy sources. Using wireless power transfer (WPT) technology for charging the battery can be considered as a good solution to overcome the battery charging time problem. The considered WPT technique in this research is an inductive magnetic resonance (IMR). The problem now is to design a smart controller system that enables the EVs to obtain the optimum value of WPT by using the machine vision and the technology of Internet of Things (IOT). The utilisation technique of the maximum WPT in this research based on the simulation study of the magnetic flux density between the sending and receiving coils of the WPT system. Maximum efficiency of IMR method depends directly on the ideality of coils alignment. To achieve this alignment, a smart controller has been introduced with four integrated controlling layers. Coordinating an image processing technique with smart embedded sensing elements is considered the main solution key to better positioning. National instrument packages NI LabVIEW and NI vision are considered to fully control the system. NI Data Dashboard enables creating a wireless link using the concept of IOT to a smartphone running simple graphical user interface. [ABSTRACT FROM AUTHOR]

Featured Application: This paper presents solutions for smart devices with embedded artificial intelligence dedicated to vehicular applications. Virtual sensors based on neural networks or regressors provide real-time predictions on diesel engine power loss caused by increased exhaust back pressure. The actual trade-off among engine emissions and performance requires detailed investigations into exhaust system configurations. Correlations among engine data acquired by sensors are susceptible to artificial intelligence (AI)-driven performance assessment. The influence of exhaust back pressure (EBP) on engine performance, mainly on effective power, was investigated on a turbocharged diesel engine tested on an instrumented dynamometric test-bench. The EBP was externally applied at steady state operation modes defined by speed and load. A complete dataset was collected to supply the statistical analysis and machine learning phases—the training and testing of all the AI solutions developed in order to predict the effective power. By extending the cloud-/edge-computing model with the cloud AI/edge AI paradigm, comprehensive research was conducted on the algorithms and software frameworks most suited to vehicular smart devices. A selection of artificial neural networks (ANNs) and regressors was implemented and evaluated. Two proof-of concept smart devices were built using state-of-the-art technology—one with hardware acceleration for "complete cycle" AI and the other with a compact code and size ("AI in a nut-shell") with ANN coefficients embedded in the code and occasionally offline "statistical re-calibration". [ABSTRACT FROM AUTHOR]

The article uses LabView to develop a fault diagnosis system for wind power planetary transmissions. First, use LabView software to create a signal acquisition system. Then, the built wind turbine planetary transmission experiment platform was combined with the NI9171 data acquisition card and the upper computer. The hysteresis brake was used in the laboratory to simulate the external wind environment, and the planetary gear transmission planetary gear crack fault diagnosis and testing experiments were performed. The frequency domain signal is obtained from the initial time domain signal obtained by the experiment through the EMD and envelope demodulation method. The frequency of the corresponding planetary gear crack in the frequency domain signal is compared with the theoretical calculation of the planetary gear crack failure frequency. The results show that the frequency of the corresponding planetary gear cracks in the frequency domain spectra obtained by the experiment is basically consistent with the theoretical calculation of the frequency of cracks in planetary gears. The fault diagnosis system developed by LabView is reliable. The experiment provides a theoretical basis for fault diagnosis, optimisation design, and life prediction of wind turbine planetary transmissions.

An unconstrained visual display terminal (VDT) visual fatigue monitoring method based on BCG is studied. A VDT visual fatigue test is designed and implemented in this study, also acceleration signals are obtained by using an acceleration sensor, which is installed on the seat back. Then, BCG is obtained by adaptive threshold wavelet denoising, FFT, frequency domain filtering in the range of heart rate, and IFFT. Low frequency (LF) is extracted after the RR interval and JJ interval are calculated by the wavelet algorithm. Curves of two kinds of LF with the usage of VDT were obtained and were identical. Thus, the authors can draw conclusions that BCG can replace ECG to achieve unconstrained monitoring of VDT visual fatigue and LF gradually increases with VDT visual fatigue becoming more and more serious. Finally, we compare LF curves of BCG and ECG during use VDT to draw a conclusion that BCG can replace ECG to monitor VDT visual fatigue in an unconstrained way. Also, the confidence interval is used to verify the reliability of SD subjective evaluation, and the conclusion is reliable.