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The evaluation of currents in circuits with ferromagnetic cores leads to troublesome graphical or numerical procedures. These difficulties may be overcome by the introduction of a simple analytical approximation of the magnetization curve directly into the inductance of a circuit. In this way one can clearly describe currents in electric circuits and magnetic induction in a toroidal core (without an air‐gap), including magnetization due to eddy currents and some other effects not considered in the commercial PSpice program.

The purpose of this paper is the modelling and estimation of inrush currents while energising power devices under no load conditions. An analytical representation of the nonlinear B-H curve serves for considering the hysteresis behaviour in the numerical model.

The model is implemented into a standard finite element formulation to compute transient problems.

Inrush currents behave like faults in power distribution facilities. Its prior estimation helps to distinguish between operating conditions and faults.

The magnetic cores may become extremely magnetised. At such high material saturations, the material characteristics are not measurable accurately. Hence, the results depend on the extrapolation of the B-H curves.

The use of first-order reversal curves within the major hysteresis loops helps in a convenient way to estimate peak and shape of the inrush currents.

The purpose of this paper is to introduce a simplified method, based on an improvement to the actual second‐order approximation to magnetic hysteresis curves, to calculate an estimation of quasi‐static hysteresis loops of ferromagnetic materials.

The addition of a new dB(B) function is proposed to second‐order rational approximation for the upward and downward magnetic quasi‐static hysteresis loop. The new semi‐empirical approach is tested with typical cycles of commercial Ni‐ferrites (ferroxcube) and Ni standards using a vibrating sample magnetometer (VSM).

The model is simple and a fast tool to reproduce with reasonable accuracy the hysteresis loops based on appropriate parameters of materials under analysis. The proposed extension to the Rivas model has reduced the maximum difference between experimental and modeled values from 19 to 0.08 per cent in the approximation to different hysteresis cycles of the magnetic materials studied here.

This paper presents an improvement to second‐order rational functions approach for fitting of hysteresis loops with simple added functions.

This paper sets out to develop analytical solution to the hysteresis, eddy current and excess losses using the T(x) model. Based on Steinmetz' postulation, the losses, represented by the area enclosed by the hysteresis loop, are individually formulated in analytical form. The model is applied to sinusoidal and triangular excitation wave forms.

The equivalent interaction fields introduced into the model represent the losses individually by applying the separation and superposition principle.

Contrary to the presently used models, this model describes the hysteresis loop with its natural sigmoid shape and describes the losses individually in simpler mathematical formulation.

Experimental verification will still be needed as to the accuracy of the model and the applicability to the various magnetic materials.

The model presented here gives a more realistic presentation of the hysteresis loop and by using simpler mathematics than other models it is more accessible to the practical user. At the same time with the easy mathematics and its visual presentation it is a great value to people engaged in theoretical research in the field of magnetics.

In contrast with present magnetic loss models, using almost exclusively MSPM with “flat power” loop or the elliptical equivalent loop approximations, these calculations based on the T(x) model of hysteresis and uses realistic shape for the hysteresis loop, resulting in a simpler mathematical formulation.

Improperly fitted parameters for the Jiles–Atherton (JA) hysteresis model can lead to non-physical hysteresis loops when ferromagnetic materials are simulated. This can be remedied by including a proper physical constraint in the parameter-fitting optimization algorithm. This paper aims to implement the constraint in the meta-heuristic simulated annealing (SA) optimization and Nelder–Mead simplex (NMS) algorithms to find JA model parameters that yield a physical hysteresis loop. The quasi-static B(H)-characteristics of a non-oriented (NO) silicon steel sheet are simulated, using existing measurements from a single sheet tester. Hysteresis loops received from the JA model under modified logistic function and piecewise cubic spline fitted to the average M(H) curve are compared against the measured minor and major hysteresis loops.

A physical constraint takes into account the anhysteretic susceptibility at the origin. This helps in the optimization decision-making, whether to accept or reject randomly generated parameters at a given iteration step. A combination of global and local heuristic optimization methods is used to determine the parameters of the JA hysteresis model. First, the SA method is applied and after that the NMS method is used in the process.

The implementation of a physical constraint improves the robustness of the parameter fitting and leads to more physical hysteresis loops. Modeling the anhysteretic magnetization by a spline fitted to the average of a measured major hysteresis loop provides a significantly better fit with the data than using analytical functions for the purpose. The results show that a modified logistic function can be considered a suitable anhysteretic (analytical) function for the NO silicon steel used in this paper. At high magnitude excitations, the average M(H) curve yields the proper fitting with the measured hysteresis loop. However, the parameters valid for the major hysteresis loop do not produce proper fitting for minor hysteresis loops.

The physical constraint is added in the SA and NMS optimization algorithms. The optimization algorithms are taken from the GNU Scientific Library, which is available from the GNU project. The methods described in this paper can be applied to estimate the physical parameters of the JA hysteresis model, particularly for the unidirectional alternating B(H) characteristics of NO silicon steel.

This study aims to use resonant surface acoustic wave (SAW) sensors, which have advantages in the harsh application environments, to measure different physical parameters such as temperature, pressure and force. For SAW sensors, the locality in measurement resolution by the effective time is poor, it cannot give the detailed results of SAW echoes.

To promote the application of SAW sensor, this paper proposes a convex program-based super-resolution measurement method to recover the missing spectral line and enhance frequency resolution.

The proposed method reduces the reliance on effective time and improves the measurement resolution of SAW sensors. The performance was validated by experiments.

The limited resolution capability restricts the benefit of SAW technology in harsh environments. The proposed method shed light on SAW measurement resolution increase, exploiting its full potential and leading to commercial applications.

Introduces a new analytical review procedure that measures the degree to which a data set’s digit distribution deviates from a Benford digit distribution. This deviation can indicate potential manipulation and can be used to signal the need for further audit testing. An artificial neural network is used to distinguish between “normal” and “manipulated” financial data. The results show that if data have been contaminated (at a 10 per cent level or more) a Benford analytical review procedure will detect this 68 per cent of the time. If the data are not contaminated, the test will indicate that the data are “clean” 67 per cent of the time. Because analytical review procedures are not used in isolation, these results probably understate the effectiveness and potential of a digits‐based analytical review procedure. This procedure’s fraud detection results compare favorably to traditional analytical review procedures. Importantly, its unique analysis procedure allows it to complement traditional analytical review procedures. A key limitation of this study is that it uses simulated data, rather than actual data. Such an enhancement will be a critical step in future research. This method appears to have potential merit and provides many opportunities for new research.

The purpose of this paper is to present a DNA hybridization detection sensor. An inexpensive fabrication procedure was used so that the sensors can be disposed economically after the measurement is completed.

Field effect transistor (FET) devices are used in the proposed structure. The FET device acts as a charge detection element and produces an amplified output current based on surface charge variations. As amplification is performed directly at the sensor frontend, noise sources have less effect on the detected signal, and thus, acceptably low DNA concentrations can be detected with simple external electronics. ZnO nano layers are used as the FET active semiconductor channel. Furthermore, a photobiasing approach is used to adjust the operating point of the proposed FET without the need for an additional gate terminal.

The proposed sensor is evaluated by applying matched and unmatched target DNA fragments on the fabricated sensors with capture probes assembled either directly on the ZnO surface or on a nano-platinum linker layer. It is observed that the presented approach can successfully detect DNA hybridization at the nano mole range with no need for complex laboratory measurement devices.

The presented photobiasing approach is effective in the adjustment of the sensor sensitivity and decreases the fabrication complexity of the achieved sensor compared with previous works.

The authors investigate the role of people-related Total Quality Management (TQM) practices, specifically metaperceptions, in hearing care students' vocational decision-making. In Italy, audiologists are health professionals and must hold a degree in hearing care. They operate according to clinical principles but must also develop marketing and commercial skills. While employers take these aspects for granted, the expectations of hearing care students often differ from reality. Thus, the authors aim to investigate the vocational expectations of hearing care students.

A survey was distributed to 600 hearing care students. Multiple regression analysis with bootstrapped confidence intervals was employed to test the hypotheses.

Students who perceived audiology as their calling were more interested in the clinical aspects than the marketing and commercial aspects of audiology. Moreover, those desiring a meaningful career path in audiology were more interested in becoming a store owner or franchisee.

Universities and recruiters should consider the influence of relevant others' metaperceptions on students' self-perceptions of their aptitudes for different careers. Universities should assist students to identify aptitudes that are relevant to career-related decision-making. In this context, people-related TQM can help students avoid incorrect aspirations and expectations.

This study is the first to investigate the role of metaperceptions from a people-related TQM perspective. Metaperceptions play a crucial role in determining the correct course of study as well as job satisfaction and expectations.

The purpose of this paper is to report on metal‐oxide‐semiconductor (MOS) capacitor‐based O₂ sensors with different catalytic metal electrode (Al or Pd), deposited on both smooth and porous surface (pore diameter ranging from 2.76 to 71.6 μm) of ZrO₂ thin film.

The ZrO₂ thin film has been prepared by RF sputtering and DC magnetron sputtering process followed by thermal oxidation process, whereas the electrodes were deposited on thin film by thermal evaporation. The sensors are exposed to O₂ gas ambient at room temperature and the O₂ sensing performance has been examined by surface characterizations and on‐line sensing electrical characterizations.

MOS capacitor O₂ sensor with Pd electrode on porous ZrO₂ thin film has the best sensitivity in term of both adsorption and desorption of gas. This sensor is proved to be operated in both capacitor and diode modes.

The paper demonstrates that room temperature MOS‐based O₂ sensor operates in capacitor and diode mode conditions with focus on the effect of ZrO₂ surface morphology on the sensing properties.