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The one-dimensional form of some types of differential equations that appear in the modeling of solid-state devices, like, e.g., the Poisson and Schro¨ dinger equations, can be solved numerically using the Numerov Process (NP). The accuracy of NP is superior by at least two orders of magnitude to that of commonly-used solution methods like, e.g.,…

Solving equations does not require only to well master the techniques but also to well understand the different underlying concepts and processes. Many of the mistakes made by the students are often due to misinterpretation of the concepts taught, especially the use of letters which the main conceptual obstacle that students have to overcome. We…

The uncertain nonlinear systems can be modeled with fuzzy differential equations (FDEs) and the solutions of these equations are applied to analyze many engineering problems. However, it is very difficult to obtain solutions of FDEs. In this paper, the solutions of FDEs are approximated by utilizing the fuzzy Sumudu transform (FST) method. Here, the uncertainties…

This article is devoted to study the existence of solutions for the strongly nonlinear \(p(x)\)-elliptic problem: \(- \Delta_{p(x)} (u) + \alpha_0 |u|^{p(x)-2}u = d(x)\frac{|\nabla u|^{p(x)}}{|u|^{p(x)}+1} + f- div g(x) \quad \text{in } \Omega, \) \(u \in W_0^{1,p(x)}(\Omega), \) Where \(\Omega\) is an open set of \(\mathbb{R}^N\), possibly of infinite measure, we will also give some…

The resolution of the Navier-Stokes and Euler equations by the finite element method is the focus of this paper. These equations are solved in conservative form using, as unknown variables, the so-called conservative variables (density, momentum per unit volume and total energy per unit volume). The variational formulation developed is a variant of the Petrov-Galerkin…

The processes of reflection of three-dimensional electromagnetic waves by locally irregular media interfaces are investigated. The problem under study is mathematically reduced to the solution of a boundary value problem for the Maxwell equations in an infinite space with an irregular boundary. In order to develop a numerical algorithm, the potential theory and a special…

In this paper, Novel (Gʹ/G)-expansion method is used to find new generalized exact travelling wave solutions of fractional order coupled Burger’s equations in terms of trigonometric functions, rational functions and hyperbolic functions with arbitrary parameters. For the conversion of the partial differential equation to the ordinary differential equation, complex transformation method is used. Novel (Gʹ/G)-expansion…

With the spread of inverters, the attention of designers naturally turned to 5-phase motors, due to their advantageous properties. In this regard, perhaps the most important issue in the design of such machines is the selection of the correct rotor slot number. Many articles have been published on multiphase machines, however, only few of them…

Metal Oxide Semiconductor Field-Effect Transistors are commonly taught in courses for electrical engineers as they are the most common components within integrated circuits. However, despite numerous papers and books on MOSFETs, students still struggle with understanding their behaviour, particularly in the saturation region. This paper presents an expanded explanation of MOSFET behaviour, with a consistent…

Most anthropomorphic robotic hands use a lot of actuators to imitate the number of joints and the movement of the human hand. As a result, the forearm of the robot hand has a large size for the installation of all actuators. This robot hand is designed to reduce the number of actuators, but also retain…

The false nearest neighbors (FNN) method estimates the variables of a system by sequentially embedding a time series into a higher-dimensional delay coordinate system and finding an embedding dimension in which the neighborhood of the delay coordinate vector in the lower dimension does not extend into the higher, that is, a dimension in which no…

On Renewable Energy (RE), this field covers the most significant share of the world energy demand and challenges on the expensive measurement and maintenance equipment to be used. In all studies and designs, global solar radiation (GSR) measurements require assessment, estimation, and models to be applied together with the environment and meteorological data on installing…

The present work develops an estimator for thermal conductivity using a simple exper- iment implemented in a simulated solid metallic bar. The bar is sectioned in a finite number of segments, lately called nodes, and a discretization of the Fourier heat equation is applied in each node to generate a timed-spaced model of the temperature…

The SENSORIA Reference Modeling Language (SRML) aims at modelling composite services at a high level. Continuous time SRML extends SRML so that it can model services whose components can perform both discrete processes and continuous processes. In order to show how continuous time SRML is applied, in this paper, we systematically introduce our study on…

This paper reports the algorithm, the input data and the result of the numeric simulation on the flows of the waves emitted from a rotating object that forms the artificial anti-gravity. First, an object with a heavy mass is placed in the 4-dimensional time and space, which is described by a fundamental tensor. Then the…

In this investigation, an integrated physics-informed deep learning and topology optimization approach for solving density-based topology designs is presented to accomplish efficiency and flexibility. In every iteration, the neural network generates feasible topology designs, and then the topology performance is evaluated using the finite element method. Unlike the data-driven methods where the loss functions are…

The paper presents the technique for the user-friendly numerical simulation of coupled oscillators described by the Kuramoto model. Oscillators couplings are defined as arbitrary 2?-periodic functions given by the Fourier series. Matlab procedure was developed to generate netlist for the equivalent electrical circuit diagram of the Kuramoto model. The input data of the procedure include…

Light Emitting Diode (LED) lamps are used as a replacement of “old-fashioned” or incandescent lighting sources, as they reduce the amount of energy consumed. As a side-effect of more efficient energy usage they produce electrical noise. This noise reduces the efficiency of information signal transfer when Power Line Communications (PLC) are used. This study focuses…

In the phosphate industry, sulfuric acid is a key compound in phosphoric acid and fertilizer production. Industrially, the sulfuric acid H2SO4 is made generally in a sequence of three main steps: burning liquid sulfur with air, catalytic oxidation of sulfur dioxide SO2 to sulfur trioxide SO3, and formation of H2SO4 by the reaction of H2O…

This manuscript intending to publicize the improvements incorporated in the BrcLightning application, including the Risk Analysis module with the help of a pop-up, which provides the result and assists in the identification of mitigating measures by the professional, which must be defined to reduce the calculated risks. Other points addressed in this extension are the…

Power converters are electronic devices widely applied in industry, and in recent years, for renewable energy electronic systems, they can regulate voltage levels and actuate as interfaces, however, to do so, is needed a controller. Proportional-Integral-Derivative (PID) are applied to power converters comparing output voltage versus a reference voltage to reduce and anticipate error. Using…

This paper presents the generalized integral transform method for solving flexural and elastic stability problems of rectangular thin plates clamped along and simply supported along remaining boundaries (x = 0, x = a) (CSCS plate). The considered plate is homogeneous, isotropic and carrying uniformly distributed transversely applied loading causing bending. Also studied, is a plate…

Discrete component based ultra-wideband SPDT switch modelling, design and implementation challenges are reported in this article. The basic SPDT switch is planned to design using PIN diodes (bare die). Nonlinear parameters extraction steps of PIN diode from datasheets have been proposed in this article instead of using readymade nonlinear PIN diode models. Equalizers are designed…

In this paper we study a cell division cycle modeled by a system of partial differential equations with an age structure. This model translates the many regulatory mechanisms within the cell cycle where it introduces the notion of phases. The individual cell can be either in I phases where the transition between theses phases are…

The undulated power supply has dropped to its worst reliability index in most parts of the city despite the installations of distribution transformers to improve the power. In this work, examination of Port Harcourt Town Zone 4 (Z4), Rivers State power distribution system forcing on its operation, planning for future expansion of the system, and…