No. 1

       Measurement of Physical Quantities

    Pages

Turgut Özseven, Zübeyir Şükrü Özkorucu:

Abstract: 

Siquan Zhang:

Investigation of Flux Transfer along Ferrite Core of Probe Coil for Eddy Current Nondestructive Evaluation

Abstract: 

A probe coil with a T-core above a layered conductor with surface hole is investigated for magnetic flux transfer along the ferrite core and enhancement of eddy currents in conductor. The cylindrical coordinate system is adopted and an artificial boundary is added to the solution domain with radius b, and the general formula for calculating the impedance of the T-core coil is derived using the truncated region eigenfunction expansion (TREE) method. For four special cases with different probe configurations, coil impedance changes due to the layered conductor and defect are calculated with Mathematica software over a frequency change ranging from 100 Hz to 20 kHz. The analytical results are in good agreement with those obtained by the finite element method and experimental measurements. The results show that under the same lift-off height and excitation frequency, the impedance change caused by the conductor or defect in the coil of long core column is greater than that of the short core column coil. It indicates that the probe coil with a long core column can transfer magnetic flux to the conductor, thereby enhancing eddy currents in the conductor.

Kiril Demerdziev, Vladimir Dimchev:

Reactive Power and Energy Instrument’s Performance in Non-Sinusoidal Conditions Regarding Different Power Theories

Abstract: 

It is important to conduct the examination of reactive power and energy instruments in normal operating conditions, due to their place in the regulated trade of electrical energy. The challenge arises when the normal operating conditions encompass non-sinusoidal voltages and currents, for two main reasons: the fact that the term reactive power/energy is not unambiguously defined in case of harmonically polluted environment and the fact that the measurement algorithm implemented in the meter is usually not explicitly presented by the producer. Different algorithms provide the same result in case of sinusoidal signals, while in case of harmonics the instrument’s performance may vary significantly, when different power theories are adopted. In the paper, a commercially available reactive energy electricity meter is tested with harmonically distorted voltage and current signals, and an analysis of its output is performed from the perspective of the implemented measuring algorithm, which is not known a priori. The tests encompass alteration of different waveform parameters and the instrument’s output is analyzed from the perspective of several reactive power theories. The conclusion of the analysis results in the meter’s performance feature illustration in correlation with different harmonic parameters and different reference conditions.

Mehmet Eren, Ramazan Gürsel Hoşbaş:

Testing the Performance of the Video Camera to Monitor the Vertical Movements of the Structure via a Specially Designed Steel Beam Apparatus

Abstract: 

This article focuses on a specially designed steel beam testing apparatus to determine the dynamics of the structure using data obtained from different sensor systems. The analysis of these different sensor systems is performed by processing data recorded by the Global Navigation Satellite System (GNSS), vision based measurement (video camera), and accelerometer surveys. To perform this analysis, the accelerometer and GNSS receiver are installed at the steel beam’s mid-span position. The high-contrast artificial target attached to the accelerometer is recorded by a video camera to monitor the structural dynamics. Steel beam experiments show that it is compatible with the accelerometer, which is predicted as a reference sensor in detecting motion with an amplitude of 10 mm and above in the vertical direction with GNSS and determining the structural frequency by spectral analysis. On the other hand, we concluded that the video camera can be used to determine the structural dynamics in SHM because its results were compatible with the reference data even if the amplitude was too small.

Hao Yang, Yufeng Lai, Xuanqi Liu, Houshi Jiang, Jiansheng Yang:

Equivalence Ratio Modelling of Premixed Propane Flame by Multiple Linear Regression Using Flame Color and Spatial Characteristics

Abstract: 

Equivalence ratio (Φ) is one of the most important parameters in combustion diagnostics. In previous studies, flame color characteristics have been widely applied to model the Φ of premixed hydrocarbon flames. The flame spatial characteristics also change with the varying Φ. In this paper, a high-speed color camera was employed to capture the premixed propane flame images under different Φ conditions (Φ = 0.93 to 1.53). Then, the relationship between the spatial characteristics and the Φ variation was investigated. The area and height of propane premixed flames perform a strong sensitive response to the Φ variation. Based on the research above, the Φ measurement models were constructed using color and spatial characteristics. A comparison was made between the color characteristics (Color-Φ) model and the color-spatial characteristics (Multi-dimensional-Φ) model. Both models were applied to a set of color images of a premixed propane flame, and the result indicates that the Multi-dimensional-Φ model performs with higher accuracy.

Bing-yi Miao, Xian-cheng Wang, Jun-hua Chen, Chu-hua Jiang, Meng-yao Qu:

A Novel Non-Contact Measurement Method of Ball Screw Thread Profile Detection Based on Machine Vision

Abstract: 

The transmission accuracy of the ball screw depends on the processing quality of the thread profile. Traditional detection method of thread profile is complicated and inefficient. When shooting the thread profile of the ball screw in the normal section, the camera axis must be tilted to the lead angle, and adjustment errors are easily introduced from both the front view and the top view. When shooting in the axial section, the spiral lines block each other, so the actual thread profile cannot be captured for detection. In order to solve the above problems, a thread profile detection method is proposed: the theoretical equation of the ball screw thread profile in the axial section is derived based on the theoretical thread profile in the normal section, and the theoretical equation of the thread profile projection curve in the axial section is solved based on helix analysis, and the differential equation between them is obtained; then, the theoretical correction value of the thread profile projection curve is obtained by Linear Search to find the boundary value; the actual thread profile in both axial section and normal section is finally obtained with the theoretical correction value, which can support accurate measurement and detection of the key parameters of the thread profile. Experiments show that the proposed method can effectively improve the accuracy of the ball screw thread profile detection.

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Shumaila Ihtisham, Sadaf Manzoor, Alamgir Khalil, Sareer Badshah4,Muhammad Ijaz, Hadia Atta:

Modeling Extreme Values with Alpha Power Inverse Pareto Distribution

Abstract: 

The study focuses on the development of a new probability distribution with applications to extreme values. The distribution is proposed by incorporating an additional parameter into the inverse Pareto distribution using the α-Power Transformation. Various properties of the new distribution are derived. The paper also explores the estimation of the parameters by the Maximum Likelihood Estimation (MLE) technique. Simulations are performed to evaluate the performance of the MLEs. In addition, two real data sets with extreme values are used to evaluate the efficacy of the proposed model. It is concluded that the proposed model performs well in the case of extreme values compared to the existing distributions.

Mikulas Bittera, Jozef Hallon, Imrich Szolik, Rene Hartansky:

Abstract: 

Even in the field of electromagnetic compatibility, low measurement uncertainty means high measurement quality. Although there are standardized procedures for obtaining the uncertainty of such a measurement, which facilitate uncertainty estimation, modern approaches show further reduction possibilities. The paper presents an alternative approach to reducing measurement instrument uncertainty in the case of electromagnetic interference measurement based on many years of our experience and a large number of measurements in this field. In the paper, two different methods of uncertainty reduction are described. The first method is based on a detailed analysis of the sources of uncertainty and the subsequent division of the analyzed frequency band into more subranges. Another method uses the choice of the antenna factor, which also contains information about the test site where the measurement is carried out. In this way, despite a lengthy analysis, it is relatively easy to achieve a measurement instrument uncertainty that is below the maximum measurement uncertainty given by the CISPR standard.

Meng-ting Xu, Hong-xi Wang, Ya-xiao Wang, Hui-hui Tian:

Abstract: 

Liping Tian, Lingbin Shen, Yanhua Xue, Lin Chen, Ping Chen, Jinshou Tian, Wei Zhao:

Abstract: 

Streak Tube Imaging Lidar (STIL), with advantages of non-scanning working mode, small distortion, high image framing rate, high resolution in low contrast environment, compact structure, easy miniaturization and high reliability, has a wide range of applications in military, aerospace, space confrontation, attack and defense, and marine law enforcement. This article introduces the principle of single-slit and multi-slit streak tube imaging lidar. It also introduces a single-slit general streak camera that can be used for imaging lidar. In addition, a multi-slit miniaturized streak tube with a single-lens focusing system with a total length of about 200 mm has been designed. The results of the 3D electromagnetic simulation show that the effective photocathode area of this streak tube reaches 36 mm × 36 mm, the temporal resolution is better than 50 ps, the dynamic spatial resolution can reach 12 lp/mm, and the whole photocathode can accommodate at least 19 slits in the effective detection range. The streak tube has a meshless structure, which is highly reliable. The streak tube can be used to increase the field of view of the imaging lidar system, improve the reliability, and achieve system miniaturization.

Khairun Nisa’ Minhad, Araf Farayez, Mamun Bin Ibne Reaz, Mohammad Arif Sobhan Bhuiyan, Siti Balqis Samdin, Mahdi H. Miraz:

L. Nurel Özdinç Polat, Şükrü Özen:

Abstract: 

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99-105

Peng Chen, Xin Su, Ting’ao Shen, Ling Mou:

A Parameter Estimation Algorithm for Damped Real-value Sinusoid in Noise

Abstract:

In order to improve the parameter estimation performance of damped real-value sinusoid in noise, a novel algorithm with high accuracy and computational efficiency is proposed, which combines the characteristics of good anti-interference, small computation of frequency-domain methods and high parameter estimation accuracy of time-domain methods. Firstly, the Discrete Fourier Transform algorithm (DFT) and two points spectrum interpolation algorithm of frequency-domain methods are used to improve the noise immunity. Then, the linear prediction property and enhancement filter of time-domain methods are used to increase the parameter estimation accuracy. In addition, the parameters estimation performance of the proposed algorithm is verified by computational complexity analysis and testing experiments, and the practical application effectiveness of the proposed algorithm is demonstrated on the Coriolis Mass Flowmeter experimental platform. The experimental results indicate that the proposed one effectively improves real time performance, and the parameter estimation accuracy is better than those of the existing excellent algorithms.

Lijun Meng, Xin Tan, Quanquan Yu:

Study on Time-frequency Imaging of Ultrasonic Detection with Phase Shifted Fiber Bragg Grating Sensing

Abstract:

The influence of the wavelength difference between the laser source and the phase-shifted fiber Bragg grating on the intensity of the power demodulation system based on an adjustable laser source was studied experimentally, and the optimum of the output laser wavelength was determined. Then, the research on time-frequency imaging damage identification based on smooth pseudo-Wigner-Ville distribution was carried out. The Time of Flight of the acoustic wave signal was calculated and time compensation was made according to the Wigner-Ville distribution and the Lamb wave dispersion curve. The ultrasonic waves before and after damage were measured with spatially arranged PS-FBGs. The difference signals were processed in a window,  and then the time-frequency energy of the normalized difference signal was imaged to assess the damage detection and location. Although the mode and group velocity of ultrasound measured by each fiber grating were different, the accurate location and identification of artificial damage in an aluminum alloy plate was realized by using only three phase-shifted fiber Bragg gratings and a smooth Wigner time-frequency imaging method.

Mathuvanesan Chokkalingam, Chinnadurai Murugaiyan:

Free-Space Optical Communication with an Optimized Lipschitz Exponent for Biosignal Telemetry

Abstract:

Healthcare monitoring is a rapidly developing network in the field of advanced medical treatment. The network combines the ideology of wireless communication, signal processing, medical information and real-time processing units to support the medical monitoring system. The proposed work focuses on the development of a Free-Space Optical (FSO) system to transmit the biosignals from a remote distance to the physician. Generally, the data transmitted over the FSO system is affected by various atmospheric conditions such as air medium, O₂, and H₂O molecules. To tackle these problems, the Biosignals  Electrocardiogram (ECG) and Electroencephalogram (EEG) are processed in the Optimized Lipschitz Exponent (OLE) Function before transmission over the FSO medium. In this novel technique, the OLE function measures the informative data from the biosignals by calculating the local regularities and singularity. This collects the most informative signals and transmits them in the signal over the FSO medium. This particular hybridization helps to transmit the required data without distortion. The bit error rate of 10^-9 is obtained, which satisfies the healthcare monitoring condition. The result section shows that the proposed model has minimum losses compared to the original signal.

Peter Andris, Ivan Frollo, Jiří Přibil, Daniel Gogola, Tomáš Dermek:

Conversion of the Bruker Minispec Instrumentation into the Static Magnetic Field Standard

Abstract:

The static magnetic field standard is part of many scientific experiments aimed at measuring the magnetic field. Often this device has to be built by oneself, if there is no possibility to buy it off the shelf. One possibility is also to convert a suitable device into a static magnetic field standard. Such a method is also described in this article. When the first experiments showed that the key parts could not be obtained under the existing conditions, it was decided to convert Bruker's Minispec into a static magnetic field standard. Such a standard will not be completely universal, but it will accommodate many experiments, and the experience may help in the future when a more perfect standard is built. This article describes the design of the apparatus, briefly describing all the equipment, which includes many parts of the original device. The parts specific to the new construction are described in more detail. An alternative solution for frequency deviation calculation using a software quadrature detector, tested only in the form of a computer simulation, is also described.  

Tomáš Húlan, Igor Štubňa, Omar Al-Shantir, Anton Trník:

The Apparatus for Thermomechanical Analysis of Clay-based Ceramics Regression Using Flame Color and Spatial Characteristics

Abstract:

A dynamic thermomechanical analysis (D-TMA) apparatus is described for measuring the resonant frequency of the flexural vibration and the internal damping of the sample using the impulse excitation technique (IET). Since the measurement is conducted at temperatures up to 1250 °C, an electromagnetic impulser is used for excitation. The free vibrations are registered by an electret microphone, stored and then converted into a frequency spectrum using the fast Fourier transform, from which the resonant frequency can be found. The furnace is built from refractory porous alumina bricks and alumina fiber pads. The heating elements are four SiC rods connected to a temperature controller. The temperature is measured with a Pt-PtRh10 thermocouple in close proximity to the sample.

Alexander Budimir, Slobodan Tabaković, Milan Zeljković:

The Influence of the Movement Method on the Results of Machine Tool Positioning Accuracy Analysis

Abstract:

The improvement of machine tools, and therefore, of industrial production, requires high accuracy of machining while adapting to the different dimensions of the workpieces and to the machines themselves. As a result, the improvement of testing procedures and the analysis of positioning accuracy results represent an important research task in modern manufacturing engineering. The paper presents the results of the research carried out with the aim of determining the influence of the choice of parameters for standardized testing of positioning accuracy on the measurement results with reference to the characteristics of the machines from the point of view of the size of the workspace and the machines themselves. In this way, it is possible to choose the appropriate test parameters of the machine tools depending on their geometrical characteristics and test conditions and within the existing standards.

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Emre Sayin, Rahman Bitirgen, Ismail Bayezit:

Attitude Control and Parameter Optimization:

A Study on Hubble Space Telescope

Abstract:

In this work, we build a satellite attitude Proportional-Integral-Derivative (PID) controlled system by using the Hubble Space Telescope (HST) parameters as a reference and tune its controller parameters using various tuning methods. First, we give the equations for the motion of a satellite. We elaborate the control structure as controller, actuator, dynamics and kinematics subsystems and construct an external disturbance model. We use a reaction wheel assembly used in the HST with the same configuration as the actuator. We evaluate the performance of the linearization by comparing it with the nonlinear model output. By working on the linearized model, we tune the PID controller parameters using two different methods: "Model-Based Root Locus Tuning” and "Genetic Algorithm Based Tuning". First, we obtain the controller parameters by manipulating the poles on the root locus plot of the linearized system. In addition, we use genetic algorithms to find the optimized controller values of the system. Finally, we compare the performances of the two methods based on their cost function values and find that the Genetic Algorithm-based tuned parameters are more fruitful in terms of the cost function value than the parameters obtained by the Root Locus-based tuning. However, it is found that the Root Locus-based tuning performs better in disturbance rejection.

Miroslav Gutten, Daniel Korenciak, Martin Karman, Peter Brncal, Matej Kucera, Tomasz N. Koltunowicz, Maciej Sulowicz:

Combination of Non-contact and Contact Measuring Methods for Analyzing Structural Conditions of Dry Transformers

Abstract:

The article describes the non-contact and contact analysis of 1-MVA dry power transformers with epoxy-resin insulation using an acoustic camera and frequency analyzer with automatic sweeping for low-middle frequency areas. Power transformers are most commonly used for construction component (core, windings, taps) analysis. The electrical, non-rotating machine generates electromagnetic and acoustic emissions that can be used to analyze dry transformers during their operation. Non-contact online diagnostic methods have many advantages over offline methods because it is not necessary to shut down the transformer, and also, the condition and behavior of the machine are analyzed during its normal operation. The article presents the analysis and comparison of structural parts of the distribution dry transformers of the same type and power. The problem of insufficient or incorrect clamp-screw connection was identified using the SFRA (Sweep Frequency Response Analysis) method.

Ľuboš Kučera, Tomáš Gajdošík, Igor Gajdáč, Lukáš Pompáš, Lukáš Smetanka, Viktor Witkovský, Gejza Wimmer:

Design and Construction of Metrological Equipment for Torque Sensors with a Carbon-based Measuring Arm

Abstract:

The paper presents a comprehensive design of metrological equipment for torque sensor verification and calibration , detailing the process from conception to construction and highlighting the specifics of the structural design to meet metrological requirements. The measuring device's functionality and the individual structural components are described, as is the methodology for creating a complete product. The paper addresses the crucial issue of measurement uncertainty and the required accuracy, achieved through the construction of a special measuring arm made of carbon material. FEM analyses of the carbon arm are presented and compared with the required metrological accuracies. In addition, we discuss the different properties of various carbon structures in Pre-preg materials used in the construction of the measuring arm and present the results of measurements on such carbon materials. This paper provides a comprehensive insight into the design and construction of metrological equipment for torque sensors, with a focus on its compliance with metrological requirements. The proposed device aims to establish the foundations for primary metrology of torque in Slovakia and has potential applications in a wide range of industries.

Supakorn Harnsoongnoen, Benjaporn Buranrat:

Glucose Concentration Monitoring Using Microstrip Spurline Sensor

Abstract:

This article reports a microstrip spurline sensor for monitoring of glucose concentration. The microstrip spurline sensor is a low-cost and easy-to-fabricate device that uses printed circuit board (PCB) technology. It consists of a combination of four spurlines and transmission lines. The four spurlines are used to reject unwanted frequencies, while the transmission lines allow the desired frequencies to pass through. The resonance frequency (F_r) and reflection coefficient (S₁₁) were recorded through meticulous simulations and experiments, within the frequency range of 1.5 GHz to 4 GHz. Additionally, the sensor was employed to detect changes in glucose concentration, ranging from 0 mg/dL to 150 mg/dL. The findings of this study indicate that the antenna-based sensor proposed in this research can effectively measure glucose levels across the diabetes range, from hypoglycemia to normoglycemia and hyperglycemia, with a high degree of sensitivity of 7.82x10^-3 dB/(mg/dL) and 233.33 kHz/(mg/dL).

Jozef Jakubík, Mary Phuong, Martina Chvosteková, Anna Krakovská:

Against the Flow of Time with Multi-output Models

Abstract:

Recent work has paid close attention to the first principle of Granger causality about the cause preceding the effect. In this context, the question may arise as to whether the detected direction of causality will also be reversed after the time reversal of unidirectionally coupled data. It has been shown recently that in the case of unidirectionally causally connected autoregressive (AR) processes X→Y, after time reversal of data, the opposite causal direction Y→X is indeed detected, although typically as part of the bidirectional X↔Y link. As we argue here, the answer is different when the measured data does not come from AR processes, but rather from linked deterministic systems. If the goal is the usual forward data analysis, cross-mapping-like approaches correctly detect X→Y, while Granger’s causality-like approaches, which should not be used for deterministic time series, detect causal independence X⫫Y. The results of the backward causal analysis depend on the predictability of the reversed data. Unlike AR processes, observables from deterministic dynamical systems, even complex nonlinear ones, are well predicted forwards while backward predictions can sometimes seem difficult (notably when the time-reversal of a function leads to one-to-many relations). To address this problem, here we propose an approach based on models that provide multiple candidate predictions for the target, combined with a loss function that takes into account only the best candidate. The resulting good forward and backward predictability supports the view that with unidirectionally causally linked deterministic dynamical systems X→Y, the same link is expected to be detected both before and after the time-reversal.

Kavitha G., Deny J.:

Single and Multi-Point Non-Orthogonal Multiple Access based Power Adaptive Design for Improving Bit Error Ratio

Abstract:

In the framework of next-generation communication systems, Non-Orthogonal Multiple Access (NOMA) has attracted considerable interest. The fundamental advantage is that it has greater spectrum utilization than its orthogonal equivalents. This proposed work integrates Single-Input Single-Output NOMA (SISO) with Coordinated Multi-Point (CoMP). It uses both systems based on Quadrature Phase-Shift Keying (QPSK). A power-tolerant NOMA reduces the system's vulnerability to erroneous power allocation by adaptively modifying each user's signal power. The transmitted data is used to modify the power in the Power-Adaptive NOMA (PANOMA). PANOMA helps improve the Bit Error ratio and also improves the computational complexity. The Bit Error Rate (BER) and the lower limit capacity efficiency across Rayleigh fading channels are determined in precise closure representations of more than two consumer situations to measure its capability. The proposed method PA-CoMP-NOMA improves the Bit Error ratio in both systems. It improves the average BER among all users. Compared to its orthogonal cousin, NOMA has higher spectral efficiency. Nevertheless, our proposed method retains this feature as well as superior BER performance, although its spectral effectiveness is lower than that of the classic sum-rate based power NOMA.

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