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Abstract Modulating the traction converters produces current harmonics at the switching frequencies and their multiples. These harmonics should be minimized to meet the network specifications. The LC‐trapped filters, tuned to these frequencies, can easily meet this requirement, but the existing applicable trap filters have not been studied with the traditional traction system topologies. Thus, this paper presents a trapped LCL filter with an LC resonator on the converter side, called a fully integrated T‐LCL filter, for the traction power supply system. The model and analysis reported in this research demonstrate that the presented filter has several advantages, which can be summarized by: reducing the size by winding many coils through magnetic integration, attenuating the switching frequency and its multiple harmonics that reduce the current total harmonic distortion, assuring durability against the filter parameters differences, and preserving system stability under transient conditions. The proposed filter can become a promising trap filter based on these advantages. Simulation models of an ac/dc single‐phase traction rectifier with the proposed filter were created and tested in MATLAB/Simulink, verifying its superiority. Finally, the filter is validated by performing hardware‐in‐the‐loop experiments.

This research delves into the radial vibrations of dissipative poroelastic spherical shells, which are embedded within an elastic foundation and subjected to rotational dynamics. The analysis identifies that the inclusion of dissipative effects gives rise to a transcendental, complex-valued frequency equation. A numerical approach, specifically the bisection method, is employed in MATLAB for solution derivation. In instances where the argument is relatively small, the study leverages the asymptotic expansions of Bessel functions, facilitating the bifurcation of the frequency equation into two distinct real-valued equations. These equations are instrumental in computing the natural frequency as a function of the shell's thickness. Furthermore, the research rigorously examines how rotational forces influence the natural frequency. The culmination of this study is presented through a series of graphical depictions, which succinctly illustrate the impact of rotational dynamics on the radial vibrations of thick-walled hollow structures situated in various elastic media. The overall findings contribute significantly to our understanding of the behavior of poroelastic materials in rotational environments, with implications for both theoretical and practical applications in material science and engineering. The results can benefit the theoretical development of orthopedic study projects connected to spherical poroelastic medium. [ABSTRACT FROM AUTHOR]

The tracking of optimal current trajectories in an interior permanent magnet (IPM) synchronous machine is traditionally realized by a complex online tracking, inaccurate analytical equations, or tiresome offline calibration methods. This paper proposes a modified hybrid feed-forward/feedback flux-weakening algorithm for IPM synchronous machines. In this paper, the utilized power converter is a standard T-type multilevel inverter, and hence, the voltage and current harmonics contents of the conventional two-level inverter are improved. The control algorithm utilizes the optimal current profile for maximum torque per ampere (MTPA) operation and a voltage regulation (VR) feedback control for efficient flux-weakening operation. For infinite-speed IPM machine drives, the d-q current components are limited to follow the maximum torque per voltage (MTPV) trajectory. A low-complexity model predictive control (MPC) is employed to minimize the conflict that arises from using cascaded PI control loops for current and speed control. The performance of the drive is investigated based on the Prius 2004 IPM parameters. Extensive simulation scenarios were performed using the MATLAB/SIMULINK which validates the effectiveness of the proposed algorithm. Real-time simulations based on the dSPACE DS 1103 platform are conducted to confirm the system validity for real hardware implementation. The proposed IPM drive system proves simple structure, fast response, and low harmonic contents. [ABSTRACT FROM AUTHOR]

The study proposes a supply chain contractual coordination model based on the product lifecycle information sharing effort and consumers' price sensitivity to a product with the Blockchain system. This paper examined the following five scenarios: (1) centralized supply chain with Blockchain system-based product lifecycle information sharing investment; (2) Stackelberg leader retailer processed and invested Blockchain system scenario; (3) retailer processed the Blockchain system cost-sharing scenario; (4) retailer processed Blockchain system investment through bargaining the revenue-sharing model; (5) Blockchain system investment under the cost and revenue-sharing contract. The study used the game theory reverse induction method to compare the Nash equilibrium solutions under different decision-making scenarios and discussed the chain member’s constraint condition of Blockchain system investment. We simulated and analysed the products’ lifecycle information sharing effort cost factor, the influence of price sensitivity coefficient, and expected profits of the supplier and retailer. The study results show that the product lifecycle information sharing effort under the Blockchain system increases the profit of the whole chain and decreases with the increase of customer’s price sensitivity coefficient.

The object of the present paper is to study the influence of the initial stress and rotation on wave propagation of harmonic waves in a human long dry bone as transversely isotropic material, subject to the boundary conditions that the outer and inner surfaces are traction free. The equations of elastodynamic are solved in terms of displacements. The natural frequency of the plane vibrations in the case of harmonic vibrations has been obtained. The frequencies and the phase velocity are calculated numerically, the effects of the initial stress and rotation are discussed. Comparisons are made with the result in the absence of rotation and initial stress.

Purpose: The present research work aims to analyze the vibration and buckling behaviour of multidirectional FG porous structures engrained with damage. Power-law (P-FGM), sigmoid (S-FGM) and exponential (E-FGM) gradings are considered to compute the material properties of the cracked FG plate. The porosity effect on the structural strength has been modelled to explore the realistic influences. Methods: In the current study, the eigenvalue analysis of the cracked FG plate with porosities is performed computationally with the help of a numerical model. The multidirectional porous structural model is repaired in ABAQUS via python script to meet the batch input. The study used the ABAQUS kernel instead of the standard GUI for better control. Results: The adequacy of the current model has been verified initially by comparing the eigenvalues (frequency and buckling load) with those of available published data with and without damages (crack). The results have been calculated for different grading patterns, porosity values, geometrical data, grading index, and crack-dependent parameters to understand their influence on the eigenvalues of the damaged multidirectional porous graded structures. Conclusions: A few generalized understandings are obtained based on the parametric study, i.e., the cracks cause a substantial decrement in total structural stiffness, which, in turn, reduces the final results adequately. Structural components are affected due to the presence of a crack in specific orientations, like in the lengthier edge of the rectangular shape. Similarly, the porosity affects the total stiffness and associated responses like the frequency and the critical buckling load. [ABSTRACT FROM AUTHOR]

Modulating the traction converters produces current harmonics at the switching frequencies and their multiples. These harmonics should be minimized to meet the network specifications. The LC‐trapped filters, tuned to these frequencies, can easily meet this requirement, but the existing applicable trap filters have not been studied with the traditional traction system topologies. Thus, this paper presents a trapped LCL filter with an LC resonator on the converter side, called a fully integrated T‐LCL filter, for the traction power supply system. The model and analysis reported in this research demonstrate that the presented filter has several advantages, which can be summarized by: reducing the size by winding many coils through magnetic integration, attenuating the switching frequency and its multiple harmonics that reduce the current total harmonic distortion, assuring durability against the filter parameters differences, and preserving system stability under transient conditions. The proposed filter can become a promising trap filter based on these advantages. Simulation models of an ac/dc single‐phase traction rectifier with the proposed filter were created and tested in MATLAB/Simulink, verifying its superiority. Finally, the filter is validated by performing hardware‐in‐the‐loop experiments. [ABSTRACT FROM AUTHOR]

The motive of these investigations is to provide the importance and significance of the fractional order (FO) derivatives in the nonlinear environmental and economic (NEE) model, i.e., FO-NEE model. The dynamics of the NEE model achieves more precise by using the form of the FO derivative. The investigations through the non-integer and nonlinear mathematical form to define the FO-NEE model are also provided in this study. The composition of the FO-NEEmodel is classified into three classes, execution cost of control, system competence of industrial elements and a new diagnostics technical exclusion cost. The mathematical FO-NEE system is numerically studied by using the artificial neural networks (ANNs) along with the Levenberg-Marquardt backpropagation method (ANNs-LMBM). Three different cases using the FO derivative have been examined to present the numerical performances of the FO-NEE model. The data is selected to solve the mathematical FO-NEE system is executed as 70% for training and 15% for both testing and certification. The exactness of the proposed ANNs-LMBM is observed through the comparison of the obtained and the Adams-Bashforth-Moulton database results. To ratify the aptitude, validity, constancy, exactness, and competence of the ANNs-LMBM, the numerical replications using the state transitions, regression, correlation, error histograms and mean square error are also described. [ABSTRACT FROM AUTHOR]