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In this paper the authors apply a three‐dimensional lumped parameter model (3D‐LPM) to evaluate the behaviour of an electromagnetic d.c. pump. Whit reference to the same device we compare the numerical approach with those illustrated in previous papers where we have described a bi‐dimensional model (2D‐LPM) and a quasi‐three‐dimensional lumped parameter model (3d‐LPM). The aim of this study is to note some important aspects of the full three‐dimensional (3D) analysis.

The paper aims to deal with the induction heating of metal billets rotating in a DC magnetic field.

The induced power distributions are analysed and the main heating parameters are estimated with reference to an infinitely long Al billet 200 mm diameter. The paper refers to the activity developed in the frame of a National Italian Project carried out by research groups of the Universities of Bologna, Padua and Roma “La Sapienza.”

The main process parameters have been evaluated for the heating up to 500°C of an Al billet 200 mm diameter.

This innovative technology appears to be very promising for improving the efficiency of the through heating of high‐conductivity metals (e.g. copper, aluminum) before hot working, by using superconducting magnets.

The paper analyses the induction heating of a infinitely long billet rotating in a uniform DC magnetic field.

This paper presents two numerical methods, which will be able to predict the temperature distribution in the thin moving conducting sheet, which is caused by the eddy‐current losses in transverse flux inductive heating devices (TFIH). The first method is based on a finite element calculation, while the second one is based on a circuit approach. The main aim of this paper is the validation of the circuit model by comparison with the more accurate and sophisticate finite element model. In addition, the results of both numerical models have also been compared with those obtained by experimental measurements.

The aim of the authors is to discuss the magnetic behaviour of the ferromagnetic materials used in industrial applications, when the cited harmonic distortion of the excitation is working. To show the characterisation of the hysteresis loops performed by these materials, various experimental tests have been executed measuring the hysteresis loops presented by a toroidal nucleus made of mumetal (e.g. that used for differential relay sensor).

The purpose of this paper is to propose a fast, accurate and efficient algorithm for assessment of transient behavior of grounding grids buried in horizontal multilayered earth model considering soil ionization effect.

The purpose of this paper is to develop a numerical simulation method to calculate the lightning impulse response of the grounding grid buried in a horizontal multilayered earth model. The mathematical model about the hybrid method based on PI basic function belonging to time domain is proposed in the paper; the mode can precisely calculate the lightning current distribution and lightning impulse response to grounding grids buried in horizontal multilayered soil model considering soil ionization effect. To increase computing efficiency, quasi-static complex image method (QSCIM) and its time-domain Green’s function closed form are introduced in the model.

The hybrid model is rather stable, with the respect to the number of elements used and with excellent convergence rate. In addition, because this mathematical model belongs to the time domain algorithm, it is very powerful for the simulation of soil ionization caused by high amplitude lightning current.

To increase computing efficiency, QSCIM and its time domain Green's function closed form are introduced in the model.

The mathematical model about the hybrid method based on PI basic function can precisely calculate the lightning current distribution and lightning impulse response to grounding grids buried in horizontal multilayered soil model considering the soil ionization effect.

Considering the soil ionization effect, the simulation calculation of lightning impulse response of substation grounding grid buried in the actual horizontal multilayered earth can effectively support the scientific and efficient design of lightning protection performance of substation grounding grid.

The hybrid model in time domain is originally developed by the authors and used to precisely calculate the lightning current distribution and lightning impulse response to grounding grids buried in horizontal multilayered soil model considering soil ionization effect. It is simple and very efficient and can easily be extended to arbitrary grounding configurations.

The purpose of this paper is to investigate the simultaneous effects of ionization and dispersion of soil on the impulse behavior of grounding electrodes under first and subsequent stroke currents.

A recently introduced technique called improved multi-conductor transmission line (MTL) is simplified for grounding electrodes buried in both-affected soils.

The simulation results show that including the two effects simultaneously in highly resistive soils under high-valued subsequent stroke current is recommended. Otherwise, simultaneous effects can be disregard.

To the best of the authors’ knowledge, there is no research on sensitivity analyses for the simultaneous inclusion of the two effects on the effective length and the induced voltage on the soil surface. To this end, the simplified MTL is applied to the grounding electrodes. The simulation results show that the computational efficiency in comparison with previous methods is, first, considerably increased. Second, the simultaneous effects result in decreasing the soil surface voltage with respect to situations where either ionization or dispersion is taken into account (single-affected soils). In other words, the performance of grounding systems is improved. Third, the effective length in both-affected soil is has a middle value with respect to the single-affected soil. Such findings practically and financially are of importance.

The purpose of this paper is to model one of the unsolved problems of magnetism, the reversal of hysteresis loops, in an analytical way. The mathematical models, describing the multiphase steel used in engineering practice, without any exception, are unsuited to provide a way to reverse the hysteretic process. In this paper, a proposal is put forward to model it by using analytical expressions, applying the reversal of the Langevin function. This model works with a high accuracy, giving useful answers to a long unsolved magnetic problem, the lack of reversibility of the hysteresis loop. The use of the proposal is shown by applying the reversal of Langevin function to a sinusoidal and a triangular waveform, the two most frequently used waveforms in research, test and industrial applications. Schematic representations are given for the wave reconstruction by using the proposed method.

The unsolved reversibility of the hysteresis loop is approached by a simple analytical formula, providing close approximation for most applications.

The proposed solution, applying the reversal of Langevin function, to the problem provides a good practical solution.

The simple analytical formula has been applied to a number of loops of widely different shapes and sizes with excellent results.

The proposed solution provides a missing mathematical tool to an unsolved problem for practical applications.

The solution proposed will reduce the work required and provide replacement for expensive complex test instrumentation.

To the best of the authors’ knowledge, this approach used in this study is the first successful approach in this field, irrespective of the required waveform, and is completely independent of the model used by the user.

This article aims to compare the LiDAR handheld mobile laser scanner (HMLS) scans with traditional survey methods, as the tree gauge and the hypsometer, to study the efficiency of the new technology in relation to the accuracy of structural forest attributes estimation useful to support a sustainable forest management.

A case study was carried out in a high forest located in Tuscany (Italy), by considering 5 forest types, in 20 different survey plots. A comparative analysis between two survey methods will be shown in order to verify the potential limits and the viability of the LiDAR HMLS in the forest field.

This research demonstrates that LiDAR HMLS technology allows to obtain a large amount of valuable data on forest structural parameters in a short span of time with a high level of accuracy and with obvious impact in terms of organisational efficiency.

Findings could be useful for forest owners highlighting the importance of investing in science and technology to improve the overall efficiency of forest resources management.

This article adds to the current knowledge on the precision forestry topic by providing insight on the feasibility and effectiveness of using precision technologies for monitoring forest ecosystems and dynamics. In particular, this study fills the gap in the literature linked to the need to have practical examples of the use of innovative technologies in forestry.

One of the intensively developed in recent years new materials are hybrid textiles modified with carbon nanotubes (CNT). In this paper, CNTs was modified by grafting dimethyl phosphite and perfluorohexyl iodine. It was applied to the cotton to obtain the flame-retardant, water-repellent, ultraviolet-resistant and conductive multifunctional fabric.

The modified CNTs were loaded onto cotton fabric by impregnation and drying. The CNTs-multi was synthesized by grafted dimethyl phosphite and perfluorohexyl chain and applied to the cotton by dipping-drying method. The surface chemistry of functionalized CNTs was characterized by Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy (XPS). The combustion properties were evaluated using a microscale combustion calorimeter, match test and TGA analysis. Surface hydrophilicity and hydrophobicity of fabric surface was characterized by static contact angle, and the UV resistance of the fabric was represented by the UPF value.

Dimethyl phosphite and perfluorohexyl chain were grafted on the surface of CNTs successively. The quantity of each component on the surface of CNTs was calculated according to XPS results. According to miniature combustion calorimeter data, both the value of maximum heat release rate (PHRR) and total heat release (THR) of CNTs -multi/cotton was about 65% lower than that of untreated cotton fabric. The residue after combustion of CNTs -multi/ cotton in the match test was more compact. The electrical conductivity of multi/ cotton is 225.6 kΩ/□, which is better than that of untreated cotton fabric. The UPF value of CNTs-multi/cotton reached 121, which was indicated that the anti-ultraviolet performance of CNTs-multi was greatly improved.

Modifying method to increase the functional component amuount on the CNTs surface still need to be explored, which could increase the hydrophobicity. How to further improve the functional effect and the general synthetic steps will be of great significance to the preparation of multifunctional modified cotton fabric.

This modifying method can be used in any of multifunctional textile preparation process. The UV-resistant and flame retardant cotton fabric was revealed as a sample for use in outdoor sports such as clothes and tents.

To meet the needs of multifunctional cotton fabric, the modification of CNTs with dimethyl phosphite and perfluorohexyl iodine has not been reported. The modified fabric has flame-retardant, UV-resistant conductive and conductive properties.