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The purpose of this research is to develop new techniques for component physical modeling for the dynamic simulation of integrated power systems.

A FE‐based phase variable model is proposed so as to achieve fast and accurate simulation. Such a model is established based on the nonlinear transient FE analysis, in order to take into consideration the harmonic effects due to the nonlinear magnetization property, magnetic circuit geometry as well as other design variations.

In the FE‐based phase variable model, the inductances are described as functions of the phase angle and the magnitude of winding currents, the rotor position and other operational parameters. They are obtained from the transient FE solutions, stored in tables, and retrieved during the simulation. The FE‐based phase variable model is implemented in Simulink in two ways. The first is the equation‐based block and the second is the circuit component‐based block. The FE‐based phase variable models of various electrical components in the power system were studied. This includes various types of rotating machines and transformers. Examination and application examples show the correctness and effectiveness of the proposed operational modeling procedures.

The developed FE‐based physical phase variable model is as accurate as the full FE model with much faster simulation speed. It will benefit the dynamic simulation of integrated power system. This combination of physical modeling and integrated dynamic simulation is original and represents an added value to the state‐of‐the‐art in this field.

The purpose of this paper is to develop a novel technique for the pre-design of a printed circuit board (PCB) of a DC-DC power converters where the placement of electric components can cancel the electromagnetic emissions through subtractive coupling and in this sense to minimize the stray magnetic and electric fields at a specific location. For this work the location of interest is a current transducer used for control purposes positioned in the center of a DC-DC Cuk converter board as a constrain.

The methodology of design is based on the development of an interface software platform through MatLab script coding which interconnects the solution of a numerical analysis software and an optimization technique. The numerical analysis software is based on finite element calculations where quasi-static field analysis are performed to calculate the radiated electric and magnetic fields. The optimization technique is conducted by genetic algorithms (GAs).

The results for the proposed procedure for PCB design show a significant reduction in radiated electromagnetic (EM) field at the susceptible device in the PCB. Even when the optimization procedure is applied only for the sensor center, the field reduction is extended for a wide region around the sensor. The proposed technique not only reduces the fundamental field component but also all the harmonic contents for the electromagnetic field. It is demonstrated that it is possible to cancel the emissions by means of varying the location and orientation of the passive elements avoiding the utilization of electromagnetic interference filters and complex modulations.

The novelty of the design procedure falls in the fitness function programming where an interface software platform is built through MatLab scripting to connect a 3D-FE analysis and the GA. The finite element analysis address the radiated EM calculation while the GA focus in the minimization of it. This computational platform has the flexibility to be easily adapted for the PCB design of any power electronic converter where the radiated EM compliance is required as well as extended to perform emissions minimization outside or/and inside the PCB.

The purpose of this paper is to propose two linear solid-shell finite elements, a six-node prismatic element denoted SHB6-EXP and an eight-node hexahedral element denoted SHB8PS-EXP, for the three-dimensional modeling of thin structures in the context of explicit dynamic analysis.

These two linear solid-shell elements are formulated based on a purely three-dimensional (3D) approach, with displacements as the only degrees of freedom. To prevent various locking phenomena, a reduced-integration scheme is used along with the assumed-strain method. The resulting formulations are computationally efficient, as only a single layer of elements with an arbitrary number of through-thickness integration points is required to model 3D thin structures.

Via the VUEL user-element subroutines, the performance of these elements is assessed through a set of selective and representative dynamic elastoplastic benchmark tests, impact-type problems and deep drawing processes involving complex non-linear loading paths, anisotropic plasticity and double-sided contact. The obtained numerical results demonstrate good performance of the SHB-EXP elements in the modeling of 3D thin structures, with only a single element layer and few integration points in the thickness direction.

The extension of the SHB-EXP solid-shell formulations to large-strain anisotropic plasticity enlarges their application range to a wide variety of dynamic elastoplastic problems and sheet metal forming simulations. All simulation results reveal that the numerical strategy adopted in this paper can efficiently prevent the various locking phenomena that commonly occur in the 3D modeling of thin structural problems.

The purpose of this paper is to present a study and analysis of insulation failure inter‐turn fault in induction machines (IMs).

A time stepping finite element method (FEM) analysis is performed for the study of IM with inter‐turn fault and determining the machine parameters (self and mutual inductances) after occurring fault. A simple dynamic model for IM with inter‐turn fault is presented. The model parameters are obtained by FEM analysis. An experimental test is also carried out to verify the results.

The behavior of IM is studied under various insulation failure inter‐turn fault conditions and severity using FEM. The paper's results help the machine designers to improve the fault tolerance as well the overall design of the machine drive system. It can also be useful for predict and detection of fault in IM.

Predicting and detection of turn faults in IM are in industry very helpful because it avoids the fully damage of IM and it is more easy to repair the machine. Designing a fault tolerant IM is required in some applications for increasing the reliability.

By using FEM for studying the fault, the machine parameters which are calculated with FEM and the study's results are very precise and accurate because the flux fluctuation after occurring fault has been taken into account. On the other hand, the fault model is very fast, global and accurate. It can be used in model‐based health monitoring systems.

This study aims to identify the main factors that drive the differences in the levels of forward-looking information disclosure (FLID) across four countries. This study goes beyond the firm-specific characteristics to the countries-specific factors to explain the observable differences in the level of FLID among the UK, Italian, Hong Kong and Chinese American Depositary Receipts (ADRs) firms trading in US Exchanges.

To validate the levels of FLID, corporate financial information environment (CFIE)-final reports structure extractor (FRSE) was conducted on the annual reports of a sample of 353 listed firm observations in 2020 across four different countries. Also, the ordinary least square regression model was used to examine the proposed relationships.

The empirical results indicate that the level of FLID is highest among the Chinese ADRs firms trading in US Exchanges and UK listed firms. Also, ownership concentration and gender diversity have a positive correlation with the level of FLID. Additionally, long-term orientation positively influences the level of FLID. Considering the moderation effect of power distance and masculinity dimensions, countries with larger power distance tend to have a lower impact of ownership concentration on the level of FLID, whereas countries with higher masculinity tend to have a lesser positive relationship between gender diversity and the level of FLID.

Notwithstanding, this study provides novel and persuasive evidence regarding the effects of firm- and country-specific characteristics as possible determinants of forward-looking disclosures, drawing on evidence from international companies with free floats, boards with female quotas and cultural values including masculinity and long-term orientation. This work offers unique insights from the upper echelons lens, which implies that firms need to obtain a critical mass of gender diversity to achieve a more balanced forward-looking perspective on their annual reports.

This study investigates the impact of international remittances on the economic growth of remittance-receiving countries, using data from 113 developing countries between 1990 and 2015.

The authors used a novel approach to address the potential endogeneity of remittances. The authors estimated bilateral remittances and use them to create weighted indicators of remittance-sending countries, which the authors then use as instruments for remittance inflows to remittance-receiving countries.

The results indicate that while remittances have a positive impact on economic growth in developing countries with high human capital, they do not contribute to growth in developing countries with low human capital. The authors also examined the channels through which remittances affect growth. The findings suggested that remittances do not impact labor supply in developing countries with high human capital, but they reduce labor supply in countries with low human capital. Additionally, remittances increase investment in physical capital in developing countries with high human capital, but they do not have an effect on investment in developing countries with low human capital.

The authors investigated the impact of remittances on economic growth using a novel approach to address the endogeneity of remittances. Additionally, the authors examined the different indirect channels through which remittances can impact economic growth, such as their effect on labor supply and investment.

The study of structures subjected to seismic action is important in countries with high seismicity. However, observation of the damage caused to these structures shows that they absorb much greater forces. The explanation lies largely in the energy dissipation mechanism. In particular, the structure’s overall behavior coefficient is “q”. The purpose of this study is to provide a method for evaluating the behavior factor and the comparison between two types of bracing of metal structures.

The aim is to provide a method for evaluating the overall behavior coefficient of structures braced with a centered bar system and an eccentric bar system and to carry out a comparative study between them. The work was carried out on three structures. The authors then estimated an average value for the “q” coefficient and a plastic hinge formation sequence was presented for each type.

As a result, the breaking of all structures is achieved by plasticization of the bars for centered bar bracing and by the formation of plastic hinges in the seismic eccentricity sections and then in the beams for eccentric bracing. The mean values of the behavior factors for centered and eccentric bar bracing are of the order of 3.5 and 2.5, respectively. The study showed that we are within the range recommended by Eurocode-8 in accordance with an average level of ductility.

The comparison between the types of bracing studied and the portal frame type shows that eccentric bar bracing is intermediate to the other two. This confirms the reliability of the study and is more dissipative than centered bar bracing.

This study aims to investigate experimentally and numerically the thermal analysis of a wavy diverging-converging corrugated enclosure, partitioned into two parts under the effect of magnetohydrodynamic (MHD) natural convection. The left part was filled with Al₂O₃/C₂H₆O₂ nanofluid, while the right part was Al₂O₃/C₂H₆O₂ saturated by a porous medium, featuring a corrugated cylinder at the center. This system is relevant to many engineering applications. Key factors affecting thermal performance, such as nanofluid volume fraction, Darcy number, Hartmann number, inclination angle of MHD and Rayleigh number, were analyzed. This study evaluated the impact of these parameters on stream function, average Nusselt number and isothermal lines under three heat source scenarios: heating the corrugated cylinder, heating the magnetic source and heating the nanofluid, porous media and corrugated walls.

The main governing equations for the nanofluid flow are mass, momentum and heat transfer, while the porous media are modeled using the Darcy–Brinkmann model. These governing equations are transformed into a dimensionless form and solved numerically using COMSOL 6.0 based on the finite-element method. Dynamic viscosity, density and thermal conductivity equations are used to calculate the properties of the nanofluid at different volume concentrations.

The results showed that increasing the Rayleigh number (Ra) and Darcy number (Da) increased the Nusselt number by 55%, indicating enhanced heat transfer. A vertical magnetic source (γ = 90°) further improved thermal performance. Conversely, thermal performance decreased with increasing Hartmann number (Ha). The highest Nusselt number was observed when the heat source was applied to the corrugated cylinder, followed by the right side with nanofluid–porous contact and was lowest for the left side with nanofluid contact. Experimental data demonstrated that the presence of a magnetic field can significantly increase the temperature, thereby enhancing heat transfer by natural convection, particularly when the heat source is applied in the region of nanofluid–porous contact.

The primary originality of this work lies in the use of a novel design featuring a diverging-converging structure with a wavy wall. In addition, it uses two types of fluids simultaneously, dividing the enclosure into two sections: the right side contains nanofluid mixed with a porous medium, while the left side is filled with nanofluid only. The system also includes a corrugated cylinder at its center with four undulations. The position of the heat source significantly influences heat dissipation. Therefore, three different positions were examined: heating the cylinder at a constant temperature, heating the left side of the enclosure and heating the right side.

The purpose of this paper is to present a comparative study of the thermal behavior and efficiency of an induction motor fed by a fault-tolerant Three-Level Neutral Point Clamped (3LNPC) inverter, under normal conditions as well as after a post-fault reconfiguration, following an open-circuit fault in the inverter. For this purpose, a Matlab/Simulink model and three-phase induction motor models using a finite element method (FEM) software were developed. Besides, some experimental tests were conducted for different values of the induction motor load torque and speed reference to validate the models.

To assess the thermal behavior and efficiency of the motor, electromagnetic and thermal models using a FEM software were developed. The coupling with the inverter drive is accomplished through a developed model in Matlab/Simulink which also includes the control system. The simulation tests were performed for a healthy and faulty inverter at different operating points of the three-phase induction motor. To validate the FEM models some experimental tests were performed.

When the inverter operates in reconfigured mode the motor losses are higher and consequently temperature is higher and the motor efficiency is lower. The developed models are an alternative to a more detailed study of the motor when fed by a 3LNPC inverter and consequent optimization of the control system.

With the developed tools, a better understanding of the motor behavior and performance is gained, allowing to forecast scenarios and optimize fault-tolerant control strategies for the drive.

In many developing and developed countries, small/medium-sized enterprises (SMEs) are a very important part of the economy and are commonly referred to as the lifeblood of the economy. SMEs in Nigeria have contributed around 48% of the national gross domestic product (GDP) in recent times and account for about 17.4 million jobs. Considering how much they contribute to national economies, it is expedient to seek ways in which they can derive value from innovative technologies to further strengthen their position. Web 2.0 technologies and associated social media applications such as social network sites, microblogging, weblogs and similar technologies are known to improve communication and collaboration among employees and customers. SMEs typically have a small budget for branding, advertising and corporate communication. Consequently, social media provides a ready and inexpensive tool that can be used to communicate with customers and for internal communication and collaboration. Several studies in the area of diffusion of innovations to SMEs argue that they do not usually use adopted technologies to its full potential and as such do not add as much value to the business. Extant research on corporate communication using social media focuses on large organizations’ adoption and use of the technology with little focus on SMEs. This contribution aims to fill this gap by considering how SMEs in Nigeria adopt and use social media to improve corporate communication.