MATLAB Program Research Articles

Theoretical investigation of the convective heat transfer mechanism along a cantilever shape

The present study aims to investigate the steady state mixed convection flow for a viscous incompressible fluid along a cantilever shape. The study has analyzed the impact of mixed convection boundary layer flow behavior and heat transfer characteristic of the cantilever shape. The leading equations for the said problem are the Navier-Stokes and energy equations. These leading equations are converted into ordinary differential equations using the stream function formulation, and the numerical solution is obtained using the shooting technique with BVP4C and built in MATLAB program. The impact of dimensionless parameters such as n, Pr, and λ on the velocity and temperature profile within the boundary layer of the cantilever cylinder is presented graphically. The results for velocity slope and temperature gradient under the effects of various emerging parameters are presented in tables. The study has concluded that mixed convection parameter has a significant impact on the velocity and temperature distribution, as well as on the velocity slope and temperature gradient rates along a cantilever shape geometry. The outcomes of the current study can be utilized for the design and optimization of various engineering devices involving cantilever shapes. Further, research regarding the impact of other parameters on the cantilever shape including heat transfer characteristics can be conducted using the approach presented in this study. The novelty of the current work can be claimed by saying that for reduced gravity, other forces involved in the flow model induced the fluid motion and temperature gradient.

Characterization of Rectangular Waveguides Loaded E-Plane Dielectrics Using the Newton-Raphson Method

Homogeneous metallic waveguides have long been used to carry high powers. They are often filled with inhomogeneous, isotropic dielectrics to reduce their size and cut-off frequencies. To characterize these inhomogeneous rectangular waveguides made of homogeneous and isotropic media, the Newton-Raphson method is used in this article. Frequency of cutoff, attenuation, and power flow distribution are all properties of the EM wave that are highly dependent on the physical structure and composition within the guide. This article presents the characterization of an inhomogeneous and isotropic rectangular guide. The analysis of this type of guide is based on the Borgnis potential method for determining the components of the electric field E and the magnetic field H, to obtain the guide's dispersion equations. The modes that were found to exist in these waveguides are hybrid, meaning that they have both axial E- and H-fields. Numerical resolution of these equations using the Newton-Raphson method obtains the guide's propagation constants. A MATLAB program is used to plot these dispersion curves. The propagation constant increases as a function of frequency, and the d/a ratio influences the dispersion curves. Increasing the relative permittivity of the dielectric leads to an increase in the ratio of the propagation constant in the z direction to the wave number.

Investigation of cable current carrying capacity improvement and its effects on transmit power between Egypt and Saudi Arabia project

This paper presents an investigation for current carrying capacity improvement of high voltage cable laid in unfavorable regions crowded with groups of high and extra high voltage power cables. A proposed MATLAB program is developed to predict the ampacity of these cables at 220 kV and 500 kV. The cables are laid in various formats and under various laying conditions. Temperature distribution inside cable layers and through soil layers are studied using a finite element model (FEM) with COMSOL software during full load operation. Calculations are based on Neher-McGrath methods in accordance with IEC 60,287. The results are compared with the manufacturer's technical guarantee. Furthermore, this paper presents a proposed cable ampacity calculation that is applied to determine the ideal cross section area for four circuits of 500 kV underground cables that will serve for future power transmission between Saudi Arabia and Egypt.

A Two-Temperature Nonlocal Poro-Thermoelastic Solid Via Higher-Order Time-Derivatives Model with Phase Lag

Abstract Purpose The present study has depicted the effect of gravitational on a two-temperature nonlocal poro-thermoelastic solid. Methods The multi-phase-lag model and fractional derivatives are used to tackle the issue. Through normal mode analysis, analytical formulas for the variable fields are derived. Using appropriate boundary conditions, the physical fields are calculated and the numerical computations have been carried out with the help of MATLAB programming. Results Through a careful comparison of the numerical data, the impacts of gravity, fractional derivative order, and locatiy on the behavior of physical fields are described. Conclusion Physical variables are affected by nonlocal thermoelasticity, fractional derivative order as well as the gravity field.

Using the Lagrange Interpolation Polynomial Method to calculate the prevalence of coronavirus disease 2019 (COVID-19) in Turkey

The goal of this paper is to look into a numerical approximation for the spread of the coronavirus disease 2019 (COVID-19) in Turkey. From March 11th to November 30th, all data is examined one by one for this purpose. The Lagrange interpolation method does not require evenly spaced x values. On the other hand, it is usually preferable to look for the closest value in the table and then use the lowest-order interpolation that is consistent with the functional form of the data. Using this method, a function for monthly and general data on the number of COVID-19 disease deaths and cases infected with the disease is obtained. Matlab programming is used to obtain Lagrange interpolation polynomials. Simulations for month by month and general data are obtained using Lagrange interpolation polynomial. The rate of spread of disease and death numbers is obtained by taking the first derivative of this function. Monthly and general tables are constructed for this propagation rate data. Peak point of the disease and different change values ​​are determined from the information in these simulations. The rates of death and spread of the disease by months are compared. As a result of this comparison, it can be seen in which months the rate of spread of disease and death increases and decreases. Monthly increase and decrease values ​​can be seen from the Figure 3-Figure 6. For example, a relative decrease can be observed in April and May

A method for the fatigue-life assessment of subsea wellhead connectors considering riser wave-induced vibration

During drilling operations, strong non-linear environmental loads are applied to the riser, which can generate powerful fatigue loads, resulting in safety hazards. This paper deals with the problem of the 330 m subsea wellhead connector in the Liu-hua 11–1, which is subjected to long-term non-linear fatigue loading in drilling conditions. Examining the fatigue response law of the subsea wellhead connector ensures the safe operation of offshore oil and gas wells. First, fatigue tests were performed on key components to obtain the stress-fatigue life curve. The F22 strain fatigue life curve was constructed based on the Neuber stress-strain relationship theory and Manson-Coffin strain-life equation. Then, the overall drilling platform - riser - subsea wellhead - soil model was established, and the bending moment-stress data of the subsea wellhead connector was obtained via finite element analysis. Then, the fatigue load spectrum was determined via the MATLAB program using the rainflow counting theory. The response characteristics of the wellhead connector fatigue damage were also compared based on four fatigue damage accumulation theories. A set of fatigue calculation and analysis methods for subsea wellhead connectors was finally developed. This method can provide reference and guidance for subsequent studies.

Longitudinal associations of diurnal rest-activity rhythms with fatigue, insomnia, and health-related quality of life in survivors of colorectal cancer up to 5 years post-treatment

BackgroundThere is a growing population of survivors of colorectal cancer (CRC). Fatigue and insomnia are common symptoms after CRC, negatively influencing health-related quality of life (HRQoL). Besides increasing physical activity and decreasing sedentary behavior, the timing and patterns of physical activity and rest over the 24-h day (i.e. diurnal rest-activity rhythms) could also play a role in alleviating these symptoms and improving HRQoL. We investigated longitudinal associations of the diurnal rest-activity rhythm (RAR) with fatigue, insomnia, and HRQoL in survivors of CRC.MethodsIn a prospective cohort study among survivors of stage I-III CRC, 5 repeated measurements were performed from 6 weeks up to 5 years post-treatment. Parameters of RAR, including mesor, amplitude, acrophase, circadian quotient, dichotomy index, and 24-h autocorrelation coefficient, were assessed by a custom MATLAB program using data from tri-axial accelerometers worn on the upper thigh for 7 consecutive days. Fatigue, insomnia, and HRQoL were measured by validated questionnaires. Confounder-adjusted linear mixed models were applied to analyze longitudinal associations of RAR with fatigue, insomnia, and HRQoL from 6 weeks until 5 years post-treatment. Additionally, intra-individual and inter-individual associations over time were separated.ResultsData were available from 289 survivors of CRC. All RAR parameters except for 24-h autocorrelation increased from 6 weeks to 6 months post-treatment, after which they remained relatively stable. A higher mesor, amplitude, circadian quotient, dichotomy index, and 24-h autocorrelation were statistically significantly associated with less fatigue and better HRQoL over time. A higher amplitude and circadian quotient were associated with lower insomnia. Most of these associations appeared driven by both within-person changes over time and between-person differences in RAR parameters. No significant associations were observed for acrophase.ConclusionsIn the first five years after CRC treatment, adhering to a generally more active (mesor) and consistent (24-h autocorrelation) RAR, with a pronounced peak activity (amplitude) and a marked difference between daytime and nighttime activity (dichotomy index) was found to be associated with lower fatigue, lower insomnia, and a better HRQoL. Future intervention studies are needed to investigate if restoring RAR among survivors of CRC could help to alleviate symptoms of fatigue and insomnia while enhancing their HRQoL.Trial registrationEnCoRe study NL6904 (https://www.onderzoekmetmensen.nl/).

Dynamics of energy transport on hydromagnetic Casson slippery nanoflow over curved surface

The study of fluid flow over curved surfaces is crucial in various engineering applications, such as designing aircraft wings, turbines, and submarines. Curved surfaces are being explored in various biomedical applications, such as designing stents for blood vessels and implants for bones and joints. Concerning the present applications of curved stretching sheets on fluid dynamics along with trihybrid nanofluids, this study is unique and fills the research gaps and offers solutions to several issues. This work looks at the flow through the boundary layer of an electrically conductive trihybrid nanofluid and the convection heat exchange of a Casson fluid across a curved stretched surface encircled within a circle of radius R. The study considers the effects of thermal radiation using the non-linearized Rosseland approximation, as well as a magnetic field, and hydromagnetic slip. The flow as well as the transfer of heat problem is mathematically described by curvilinear coordinates. Using the combination of the shooting technique and the Runge-Kutta method, similar solutions to the modeled partial differential equations are produced, and the set of non-linear ordinary differential equations with a boundary value solver is implemented through the MATLAB program. The study finds the influence of several limits on critical characteristics such as fluid velocity, coefficient of skin friction, pressure, temperature, and rate of heat exchange over a surface. The findings are shown in tables and graphs. Additionally, a comparative analysis between the current findings and those found in the literature is provided. Blood-containing nanoparticles (GO-SWCNTs-MWCNTs) on curved surfaces could improve drug delivery effectiveness, growth of synthetic tissues or organs with complex structures and effective cancer therapy treatment.

A software model to generate permutation keys through a square matrix

Information security and data protection are among the key aspects, which should be intensively developing in the 21st century. A conventional approach to cryptographic algorithms offers to apply matrices to represent information. However, more recent approaches deploy other data structures, including permutations, thus necessitating accordance between differing data structures to integrate different methods into a wholistic system of processing and transmitting information. This study aims to generate permutations, which serve as a key for factorial data coding according to a known key matrix. The paper presents two algorithms for transforming a square matrix into a permutation. An example of matrix transformation following each of the proposed algorithms is given. A software model was created and described to investigate the transformation of square matrices into permutations with the Matlab software product. The authors have considered the built-in methods of statistical information processing in the Matlab program and their graphical representation by built-in functions, which are applied in the process of the software model. A matrix transformation has been performed according to the proposed algorithms. The paper investigates all possible combinations of a square matrix of order 2 with elements referring to the finite integer field modulo p = 17 and p = 23. According to each transforming algorithm, the results of a square matrix transforming into a permutation number are obtained in the lexicographic order. The statistical properties of the obtained results have been studied, and the most efficient algorithm for transforming matrices into permutations has been determined based on the distribution uniformity criterion for the generated permutation numbers. The study demonstrates that this algorithm can potentially be deployed in information exchange systems based on factorial data coding

High directivity microstrip patch antenna design using binary ebola search optimization for radio frequency identification application

Microstrip patch antenna has gained significant popularity in wireless communication field, because of its compact size, less profile, and ease of installation. It is widely used in various applications such as Radio-Frequency Identification (RFID) systems, where dependable and long-range communication is made possible by the great directivity and efficiency. In this manuscript, a High Directivity Microstrip Patch Antenna design using Binary Ebola Search Optimization for Radio Frequency Identification Application (MPA-RFID-BESO) is proposed.The design of microstrip patch antennas is the difficulty in achieving high directivity while maintaining compact size and low profile. This research explains design and application-specific optimisation of the Microstrip Patch Antenna (MPA) of biomedical utilizing Binary Ebola Search optimization (BESO) algorithm. Microstrip patch antenna is designed to function in double and multi band applications due to its low cost, light weight, and ease of installation. MPA is made with flawed ground construction to lessen cross-polarized radiation emitted by microstrip patches and to achieve the necessary radiation parameters. Here, the cost of the materials is reduced by using a liquid crystal polymer substrate, and aerial performance is enhanced by using the appropriate geometrical parameters. The small design of the BESO optimised improves the performance of antenna as 50 mm×50 mm compact size. The MATLAB program uses high frequency to do the simulation method. The proposed antenna design is a preferable option for applications involving Radio Frequency Identification (RFID). The performance metrics, such as radiation pattern, constant gain, directivity, bandwidth, and antenna efficiency and return loss are measured and compared to the existing techniques. The proposed MPA-BA-BESO design provides 10.51%, 12.85% and 16.04% higher bandwidth and 23.63%, 47.86% and 32.06% higher gain compared with existing designs, like Designing MPA utilizing Moth–Flame optimization approach (MPA-UWB-MFOA), Predicting Rectangular Patch Microstrip Antenna Dimension utilizing Machine Learning (MPA-ANN), Dual Band Antenna Design and Prediction of Resonance Frequency Utilizing Machine Learning Algorithms (DBAD-RF-CNN) respectively. The proposed technology serve as a better design alternative for microstrip patch antennas in communication systems to address biological applications.

Numerical Comparison by using Some Criteria to Estimate the Two Parameters of the Exponentiated Exponential Distribution

The present paper shows a numerical comparison by using the number of the following criteria: mean squared, root mean Square, mean absolute, and relative mean squared error values between the methods, namely maximum likelihood and Bayesian estimators for the two parameters of the exponentiated exponential distribution. In estimating the maximum likelihood, The equations cannot be solved directly, Then Newton-Raphson method is used. Because of Bayes estimators under scale invariant squared and weighted composite linear-exponential loss functions the ratios cannot be simplified in a closed form. So, we use Lindley approximation. MATLAB program is used to display the results.

Exact Solutions for the Modified Burgers Equation with Additional Time-dependent Variable Coefficient

In this article, we investigated new travelling wave solutions for the modified Burgers equation with additional time-dependent variable coefficient via the functional variable method. The performance of this method is reliable and effective and gives the exact solitary wave solutions. All solutions of this equation have been examined and three dimensional graphics of the obtained solutions have been drawn by using the Matlab program. The exact solutions have its great importance to reveal the internal mechanism of the physical phenomena. This method presents a wider applicability for handling nonlinear wave equations.

Effect of surface roughness parameters on frictional properties of AlSi10Mg alloy

Experimental study of the effects of surface roughness parameters and their relationship to the coefficient of friction (COF) on AlSi10Mg alloy. The information demonstrates that the average surface roughness (Ra) does not directly correlate with COF when sliding is presented. This work is focused on the relationship and interaction between the roughness parameters (Ra), maximum profile height (Rt), average profile slope, and COF. To alter the surface roughness effect, the samples of the alloy are chemically treated with an alkaline 0, 5, 10, 15, 25, and 50 minutes and tested under different circumstances. Using a T-05 block-on-ring tribometer, the COF is calculated, and surface roughness measurements are collected utilizing an optical system for measuring three-dimensional surfaces. The program MATLAB is used to analyze the obtained data. Contrarily, the results demonstrate that there is a substantial positive association with COF under sliding conditions, while Ra and Rt can change without affecting CO significantly.

Numerical modeling for representation of wave-induced currents. Application to the port of Ilo-Peru

The objective of this article is to represent the wave-induced currents in the areas near the port of Ilo, with the use of SMC software and a self-developed program in Matlab. In the present study, the parabolic RefDif, for a monochromatic wave model was used for the wave module. The numerical model developed in Matlab allows representing the hydrodynamics of waves and induced currents based on the Navier Stokes equations and mass conservation, in differential form with two spatial dimensions (x, y) and one temporal (t). This model was developed taking into consideration the variables averaged in the vertical z axis and variable draft, considering the phenomenon of protrusion and refraction that the waves suffer when approaching the coastal zone of shallow waters. The model developed in Matlab was validated for the simplified case of straight beaches

Multi-Attribute Decision-Making Method Based on Dispersion Maximization and its Practical Application

Multi-attribute decision making is an important part of modern decision science, which has wide and practical applications in engineering design, economy, management, military and other fields. This paper first introduces the theory and sequencing steps of multi-attribute decision making method based on deviation maximization, and then makes specific application to the example of civil servant recruitment in government departments by using MATLAB programming. It makes the operation process of recruitment work clear and clear, and realizes scientific, normative and fair.

Моделирование установки замедленного коксования в программе MatLab

In order to prevent the occurrence of an emergency situation in the oil and gas industry, it is necessary to use control, automation and alarm systems. In this regard, artificial intelligence technologies have recently become in-creasingly popular. Neural networks are of particular interest. To implement the task of regulating, automating and predicting technological processes in the oil industry, it is possible to use neural network modeling of chemical and technological processes. Examples of using neural network modeling in practice are given. The results of neural network modeling of a delayed coking plant of one of the operating enterprises are presented. A delayed coking installation was modeled in the UniSim Design software package, which allowed us to obtain an initial data array for a neural network. The neural network was built in the MatLab program, and the program code was created. Graphs of error and regression are presented. The analysis of the results presented on the regression and error graphs is given. As a result of testing the model, minimal discrepancies between experimental and predicted data were obtained, which indicates the adequacy of the neural network model. An additional test of the program was also performed. The results of training and testing of the model are presented. The results obtained can later be used to create programs at different levels of control, since the model allows you to estimate the amount of losses during the operation of the installation at a certain flow rate of feed water supplied to the installation as a turbocharger.

Numerical Integration and Angular Spectrum Modeling of Resonant and Non-Resonant Wave Interaction with a Solid Plate

The angular spectrum (AS) model is widely used to calculate the pressure transmitted through, and reflected from, a fluid-immersed solid plate, using a baffled piston as source. However, narrow peaks (infinite peaks for the lossless case) in the piston aperture function and in the plane wave transmission and reflection coefficients, in addition to a highly oscillatory integrand, cause challenges in the numerical integration. To overcome the challenges related to the aperture function peak, the AS model is reformulated using integration by parts. The peaks in the transmission and reflection coefficients are identified as symmetric and antisymmetric Scholte modes, and a numerical integration method is provided enabling integration over these peaks. The AS-model is also used to obtain the full-wave diffraction correction for a pulse-train transmitted through, or reflected from, the plate, which is highly relevant in pulse-transmit or pulse-receive measurements. The diffraction effects caused by the plate are calculated by suppressing resonance effects in the plate and obtaining the corresponding plane wave pressure transmission and reflection coefficients. A hybrid Gauss-Filon adaptive numerical integration method is used to calculate the pressure. These calculations are conducted in APAS, a MATLAB program developed in the current work and provided as open-source supplementary material.

A semi-analytical simulation method for bi-directional functionally graded cantilever beams under arbitrary static loads

This paper presents a novel semi-analytical simulation approach for analysing the behaviour of bi-directional functionally graded cantilever beams subjected to arbitrary static loads, such as concentrated moments, concentrated forces, distributed force and their combinations applied at any location along the beam. The fundamental equations governing the cantilever beam’s response are derived, on the basis of which the proposed semi-analytical method is implemented using MATLAB programming language. The simulation results include field variables as well as stress contours, providing a compressive understanding of the beam’s behaviour. To validate the accuracy and reliability of the proposed method, a convergence study is conducted in comparison with the graded finite element method (GFEM) and analytical solutions. In the end, the developed method is applied to simulate the bending behaviour of bi-directional functionally graded cantilever beams under various loads individually and their combinations. The stress contours and deflection curves obtained from the simulation are compared with the solutions obtained using GFEM, revealing that the developed method possesses excellent capability in accurately simulating the bending behaviour of cantilever beams.

Numerical Study on Permeability of Reconstructed Porous Concrete Based on Lattice Boltzmann Method

The reconstruction of the porous media model is crucial for researching the mesoscopic seepage characteristics of porous concrete. Based on a self-compiled MATLAB program, a porous concrete model was modeled by controlling four parameters (distribution probability, growth probability, probability density, and porosity) with clear physical meanings using a quartet structure generation set (QSGS) along with the lattice Boltzmann method (LBM) to investigate permeability. The rationality of the numerical model was verified through Poiseuille flow theory. The results showed that the QSGS model exhibited varied pore shapes and disordered distributions, resembling real porous concrete. Seepage velocity distribution showed higher values in larger pores, with flow rates reaching up to 0.012 lattice point velocity. The permeability–porosity relationship demonstrated high linearity (the Pearson correlation coefficient is 0.92), consistent with real porous concrete behavior. The integration of QSGS-LBM represents a novel approach, and the research results can provide new ideas and new means for subsequent research on the permeability of porous concrete or similar porous medium materials.

A numerical study on fractional order financial system with chaotic and Lyapunov stability analysis

In the last few decades, academic research has focused more on financial problems and poverty levels. These are among the two major challenges of the modern world today. To understand the challenge of financial crisis and poverty in societies. This paper explains a deterministic financial system of non linear differential equations. Which aim to provide recommendations to address the twin challenges. In this fractional chaotic model, memory and chaos are portrayed as effects on a system. Financial systems of fractional order have three compartments: interest rate x(t), investment demand rate y(t) and price indexes rate z(t). For the first time, the Legendre wavelet approximation is applied to fractional order financial systems. A major objective of this process is to convert fractional differential equations (FDEs) into algebraic equations by using Legendre wavelets and their fractional integral operators. For residual analysis, convergence and stability analysis, we have used iteration methods and Legendre wavelets. This study indicates good results between the approximate and numerical solutions and that this method is efficient and accurate. Using the iteration method, we prove that the solution exists, while the contraction theory proves its uniqueness. The findings of this study will be extremely useful for future financial management. We have demonstrated the applicability and effectiveness of these methods by analysing numerical simulations for the fractional order financial model and the numerical simulation has been calculated by MATLAB programming.