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Finding important nodes in complex networks is an important topic. However, the location information obtained by many previous studies is not sufficient and effective, and the types of attributes applied also have limitations. Based on K-shell and gravity model, this paper proposes a node importance measurement method based on multi-attribute fusion. In this method, the objective, comprehensive evaluation of multiple attributes is obtained by the entropy weight method. Experiments on real networks show that the proposed algorithm can effectively measure the importance of nodes. [ABSTRACT FROM AUTHOR]

In this paper, we propose a new architecture of 1 × 2 , 1 × 4 , 1 × 8 and 1 × 1 6 optical filter/power splitters operating around 1.55 μ m, based on a CPs 2D photonic crystal ring resonator for Modern Passive Optical Network (PON). This type of functionality, filtering/power splitting is introduced in this work for the first-time according literature. The designed device consists of a square array of GaAs dielectric rods immersed in air. The structure is designed and successfully simulated by the finite element method using the software COMSOL Multiphysics. From the results obtained, we note that the beam is evenly distributed for all output ports with total efficient transmissions of about 99.6%, 98.8%, 97.1% and 96.8% and low insertion losses of about 0.017, 0.052, 0.128, and −0.14 dB for the 1 × 2 , 1 × 4 , 1 × 8 , and 1 × 1 6 filter power splitter successively. [ABSTRACT FROM AUTHOR]

The desalination process using membrane distillation (MD) has recently attracted wide attention in the last few years around the world. Especially, membranes that have an asymmetric geometry, for their performance to filtrate the salt water and the high salt rejection. In this paper, the Langevin dynamics model was adopted as a simulation method to investigate the transport of salt water through the sloping membrane under a pressure drop. The surface of the used membrane is considered as a hydrophilic sloping surface. Thus, the pressure drop effect on the fluid flux was observed, which leads to attracting the salt water into pores that are randomly distributed. The influence of deposition and accumulation of the ions into pores, the incline angle of the membrane surface, and the thickness of the formed layer on the surface were investigated. In addition, the impact of biofouling is caused by the accumulation and the variation of the fluid velocity as a function of pressure drop values. The obtained results show that the relationship between the fluid velocity and the pressing force is a power law. Moreover, the increase in fluid flow velocity in the porous medium is severe in the earlier time regime, but it becomes almost constant in the second regime. However, the time desalination process increases linearly with the pressure drop. Moreover, the accumulation and deposition of ions into the pores cause a decrease in the water flow through the pores resulting in a higher pressure drop in the less inclined direction. Finally, the influence of deposition and accumulation of the salt phase into the pores on the membrane performance was remarked, resulting in a high desalination rate. The obtained results explain the salt water behavior through a porous membrane, which provides ideas for making a high membrane performance. [ABSTRACT FROM AUTHOR]

In this paper, we demonstrated the ability of a hexagonal photonic crystal fiber (PCF) with a hollow core infiltrated with nitrobenzene (C6H5NO2) to generate a broad SC spectrum at low peak powers. Due to the non-uniformity of the air hole diameters, our new design allows for simultaneous optimization of features, resulting in near-flat, near-zero dispersion, a small effective mode area, and low attenuation for efficient spectral broadening. We selected two optimal structures from the simulation results to analyze the nonlinear properties and supercontinuum generation. The first fiber, #HF1, with a lattice constant of 1.0 μ m and a filling factor of 0.45, operates in all-normal dispersion and produces spectral SC ranging from 0.81 μ m to 1.919 μ m with a pump wavelength of 1.56 μ m, a pulse duration of 90 fs, and peak power of 0.133 kW propagated in a 1 cm fiber length. The #HF2 fiber (lattice constant of 2.0 μ m, filling factor of 0.3) has an extended SC spectrum from 0.792 μ m to 3.994 μ m, a pump wavelength of 1.55 μ m, a pulse width of 110 fs, a peak power of 0.273 kW propagated in a 15 cm fiber length. The proposed fiber may be a new-generation optical fiber suitable for low-peak power all-fiber optical systems to replace glass-core glass fiber. [ABSTRACT FROM AUTHOR]

The noise attenuation ability of a single material or structure, especially for low-frequency noise, is limited by its thickness. Aiming to achieve high-efficiency noise attenuation at low frequencies, this paper proposes the methods of porous material filling and micro-perforated plate (MPP) embedding to design a perfect sound absorber at different frequencies using the under-loss Helmholtz resonator (HR). Based on the transfer matrix method, the theoretical calculation models of the sound absorption coefficients of the HR, Helmholtz resonator with porous material (HRP), and Helmholtz resonator with micro-perforated plates (HRM) are constructed. Based on the theoretical models, the under-loss absorber HR1 with the peak absorption at 243 Hz, and the HRP and HRM with perfect absorption at 212 Hz and 157 Hz are designed, respectively. The impedance analysis and complex frequency plane method are used to analyze the sound absorption mechanisms of the HR1, HRP, and HRM. The accuracy of the theoretical model is verified by the finite element method. Finally, the three acoustic absorbers are manufactured using 3D printing technology, and the absorption coefficients are evaluated experimentally. The experimental results show that the HR1 has a high working frequency at 245 Hz and a narrow bandwidth of high-efficiency sound absorption (α > 0. 8), which is only 12 Hz. The working frequency of the HRP is 214 Hz, and its high-efficiency sound absorption bandwidth is 54 Hz. The HRP has the lowest working frequency at 157 Hz and the widest high-efficiency sound absorption bandwidth of 58 Hz among the three absorbers. The research results presented in this paper provide a reference for the realization of low-frequency broadband noise attenuation designs and have certain application potential in noise control. [ABSTRACT FROM AUTHOR]

Angular velocity is a very important measurement parameter for autonomous driving and industrial applications. The design of MEMS quartz gyro measurement and control circuit has always been the key to restricting the measurement angular velocity performance of gyro system. This paper introduces the application-specific integrated circuit (ASIC) design and implementation of a MEMS quartz gyro measurement and control circuit for angular velocity measurement. The designed nonlinear multiplier can use a square wave to drive the gyro's sensitive structure at the beginning of gyro start-up, thereby reducing the gyro power-up time. The drive circuit replaces the PLL with an automatic gain control unit composed of peak detection and proportional integration (PI) controller, which makes the MEMS gyro system have good robustness. First, SIMULINK is used to model and simulate the MEMS gyroscope system-level model, which illustrates the feasibility of the drive circuit design scheme. Then, the operating principle of the drive loop is analyzed, and the design of the key circuit modules of the measurement and control circuit is introduced. Finally, the performance of the gyroscope drive and detection circuit is experimentally tested, the amplitude and frequency uncertainty of the gyroscope drive circuit are evaluated, and the bias instability and nonlinearity of the gyroscope are tested, the experiment results show that the gyroscope has good performance. [ABSTRACT FROM AUTHOR]

In this paper, a novel digital closed-loop interface circuit system of MEMS vibrating gyroscope is proposed, which includes driving, detection and quadrature circuits. Because of the high sensitivity and precision of the MEMS gyroscope, the interface circuit system is established under the condition of mode separation. The driving circuit of MEMS gyroscope adopts digital automatic gain control (AGC) to realize self-excitation closed-loop control, which makes the gyroscope system simple in structure and good in robustness. First, the working principle of the gyroscope's sensitive structure is introduced and the system simulation model of the sensitive structure is developed. Second, a Σ Δ ADC and DAC with single-bit output are designed and the feasibility of the driving circuit design is verified by the system-level model. Third, the quadrature closed-loop correction circuit is designed to reduce the coupling of the quadrature component to the gyroscope detection circuit. The simulation results show that the quadrature correction loop can effectively reduce the influence of the quadrature coupling on the detection loop of MEMS gyroscope. Finally, the system-level model of the gyroscope is established by SIMULINK, the overall system performance of the gyroscope is analyzed, and the test system of MEMS gyroscope is built by field-programmable gate array (FPGA) and application specific integrated circuit (ASIC). The experiment verifies the feasibility of the digital interface circuit design, and the zero-bias instability of the gyroscope system is 1.0∘/h. [ABSTRACT FROM AUTHOR]

Coherent anti-Stokes Raman Scattering (CARS) spectroscopy is a nonlinear optical technique that is used to investigate many different chemical and biological systems. This tool is very efficient and essentially completely rejects fluorescence. As is well known, the excitation profiles of resonance CARS are mostly used to estimate the origin shift parameters with electronic excitation for vibrations with resonantly enhanced Raman components that give information about the molecular structure and its changes in an excited electronic state. Certainly, it is necessary to have an appropriate theoretical model for pragmatically representing these processes and considering the joint (simultaneous) impact of different broadening mechanisms. The theoretical model presented in the paper is the most general and is free from a priori assumptions. Also, the mathematical algorithm created on its basis is flexible and fast for quantitative calculations. [ABSTRACT FROM AUTHOR]

The diamagnetic susceptibility and binding energy (BE) of a hydrogenic donor confined in a GaAs/AlGaAs QWW were theoretically studied in this paper under the influences of the applied laser field, QWW geometry, and non-parabolicity using variation technique combined with effective mass approximation. In the first part, the diamagnetic susceptibility and BE of the donor at the ground state are studied as a function of the size of the QWW, geometry, and applied laser field. The results reveal that changing the geometry of QWW enhances the quantum confinement effects. However, increasing the laser field reduces the BE by adding screening effects to the Coulomb interactions. Further, the diamagnetic susceptibility is available with the stability information about the carrier–parent donor system based on the mean square separation between them. It also demonstrates that susceptibility may remain stable regardless of the change in geometry and applied laser field. Thus, the diamagnetic behavior can serve as a better tool to evaluate the stability and Mott transition of donors in QWW. In the second section, the consequences of laser field and geometry on the SMT of confined donors in QWW have been studied. It is observed that the BE of donors remains constant until N ∼ 1 0 1 5  cm − 1 beyond which it starts to decrease gradually and vanishes exactly at critical concentration ( N c). However, the diamagnetic susceptibility of the donor has remained constant until reaching N c , beyond which it turned into a drastic fall, which manifested the SMT in the system. The current work is expected to add a few noteworthy points to the SMT phenomena in nanostructures. [ABSTRACT FROM AUTHOR]

Unconventional superconductivity on a honeycomb lattice has received increasing interest since the discovery of graphene primarily due to the similarities between materials with a honeycomb lattice and cuprate superconductors. Many theoretical studies have been conducted on superconductivity on a honeycomb lattice, however, a consistent picture is still lacking. In this paper, we have extended the theory of kinetic-energy-driven superconductivity, which has been developed to investigate unconventional superconductivity in cuprate superconductors, to explore superconductivity on a honeycomb lattice within the t-J model. Our results demonstrate that the charge-carrier pair gap parameter with d x 2 − y 2 + i d x y -wave symmetry exhibits a dome-like shape as a function of doping, with superconductivity emerging at a certain doping concentration and disappearing at high doping levels, similar to what has been observed in cuprate and cobaltate superconductors. Furthermore, the charge-carrier pair gap parameter decreases with increasing the value of J ∕ t (the ratio between the antiferromagnetic exchange coupling constant and the nearest-neighbor hopping integral), and approaches zero when J ∕ t reaches a sufficiently large value. This indicates that the antiferromagnetic order will suppress the superconducting state and a sufficiently strong exchange coupling will completely destroy the superconductivity. Taking into account our present results together with the corresponding results of cuprate and cobaltate superconductors, it appears that the dome-like shape of the doping dependence of the charge-carrier pair gap parameter may be a common feature in doped Mott insulators. [ABSTRACT FROM AUTHOR]

The goal of this probing is to scrutinize the impact of chemical reaction and radiation on the flow behavior of a nanofluid, made up of copper nanoparticles suspended in water, as it moves through a vertically oscillating plate in a magnetohydrodynamic free, unsteady convective system. We tackled the problem with a mathematical model incorporating nanoparticle volume fraction and used a closed-form Laplace transformation method to resolve the governing equations for momentum, energy, and concentration field. The results were also depicted graphically with heat transport rate, mass transport rate, and skin friction illustrations. The study shows that increasing the volume fraction of Cu–water-based nanoparticles decreases primary and secondary velocities, while the temperature field grows. Moreover, a higher chemical reaction parameter leads to a drop in the fluid concentration. Furthermore, a graphic representation of the upshots of variant dimensionless parameters on the nanofluid velocity, temperature, and species concentration is provided. The subject of this paper explores an extension that involves the inclusion of Cu–water-based nanofluid. This nanofluid exhibits significantly higher thermal conductivity compared to typical fluids. Consequently, it can be considered a superior alternative to conventional fluids, proving to be valuable in enhancing heat transfer in diverse engineering and industrial processes. This study is significantly relevant to various industrial and machine-building applications. [ABSTRACT FROM AUTHOR]

Layered metal composites have been widely used in various industries fields because of their excellent properties and are responsible for mechanical behavior of materials. This paper focuses on analyzing the deformation mechanism of the (110) interface under different loading states by MD. The results show that there are two yield points in the stress–strain curve under both Z- and Y-axis loading states. The first yield is the nucleation of dislocations at the interface, meantime the slip of dislocations and the extension of stacking faults begin at the Al layer. The second one, the dislocation passes through the interface, nucleates and emits toward the Cu layer at the interface, leading to a stress mutation. It is worth noting that during the stable rheological stage, the deformation mechanisms vary under different loading directions. Under Y-axis tensile loading, the phase transformation of FCC–HCP is present due to the interaction of dislocation movement and stacking fault. On the contrary, there are two twin paths A and B, improving the strength, during Z-axis compression loading. For other loading modes, there are three zones, namely the elastic stage, the release of energy, and strain hardening and dynamic softening. The interface plays the role of nucleation, annihilation and penetration of dislocations, and this interface-dislocation mechanism is reflected in the whole stage of plastic deformation. The results have an insight into the design and control in heterointerface. [ABSTRACT FROM AUTHOR]

In this paper, a numerical framework for modelling multiphase flows with interface correction is proposed. In original Volume-of-Fluid method, the interface smearing may appear since the interface profile deviates from its equilibrium state, especially in the simulations of complex interface deformation. To solve this problem, a novel correction step is introduced into the procedure after solving the volume fraction transport equation, and this step just works on the region of phase interface. The difference between the current method and the previous work is that the correction coefficient can be adjusted adaptively with the gradient of normal velocity at the interface, which is strongly correlated to the intensity of interface smearing and changes with the computational time and interface position. The validation computations are performed for bubble deformation (initial shapes of two-dimensional four-lobed-star and three-dimensional (3D) box with holes), bubble rising in a channel and Rayleigh–Taylor instability problems (Reynolds number of 100 and 1000). The obtained results show that the unphysical phenomenon of interface smearing is suppressed effectively, and the interface sharpness is improved greatly by the present method. In addition, the mass of bubble deformation by the original method will decrease by 13.3%. While these results obtained by the present method are in good agreement with the analytical solutions or published data. [ABSTRACT FROM AUTHOR]

The robustness of complex networks to various kinds of attacks that could trigger cascading failures has attracted increasing attention. Most existing studies fail to consider that the cost to attack each network component (node or edge) may be unequal. Therefore, in this paper, we explore the network robustness to cascaded attacks based on heterogeneous costs. We introduce an attack cost model with both cost-sensitive and budget-constraint parameters. On this basis, three attack strategies are considered, including hub strategy, average degree strategy, and leaf strategy. Their cascaded attack effects are compared by considering the load local preferential redistribution rule. Both the fraction of failed nodes and the value of a new robustness metric, i.e. the budget-constraint threshold, are monitored in different complex networks. Numerical experiments indicate that as the attack cost changes from homogeneity to heterogeneity, the performance of the classic hub strategy decreases gradually. For the situation of weak heterogeneity of attack cost of each node, leaf strategy achieves the maximum attack performance gradually. Moreover, the budget, network structure, and robustness metrics may all affect the selection of the optimal attack strategy. [ABSTRACT FROM AUTHOR]

A theoretical analysis on the influence of photothermal effects on the photoconduction of one-dimensional (1D) carbyne nanostructures has been explored in this paper. It is found that the size dependence of photoconduction is a great benefit from the change of band structure and optical absorption, while the influence of photothermal effect on the photoconduction is mainly induced by the grain boundary scattering and transport properties. Moreover, the photoconduction increases as the incident power enhances with a P 0 γ dependence and γ is not only related to the illumination intensity but also modulated by the dimensions. Our predictions are consistent with the available evidence, which indicates that our model is crucial for the understanding of the physical mechanism on the photothermal effect of 1D carbyne nanostructures and for their potential applications in nanotechnologies. [ABSTRACT FROM AUTHOR]

The effect of surface roughness, magnetic field, and couple stress on the performance of secant slider bearing is studied in this paper. The effectiveness of the bearing is assessed by using a couple stress liquid as the lubricant in the process. Because of microstructural impacts, couple stress fluids have distinctive rheological characteristics. These features have the potential to make a major impact on the bearing's performance. The novel aspect of this study is that the roughness of the secant slider is taken into consideration. The modified Reynolds equation is derived using Christensen's stochastic theory for roughness. Here, both transverse and longitudinal roughness patterns are considered. The analytical solutions are obtained for steady-state pressure, load-carrying capacity, film stiffness, and damping coefficient. The results are presented for various parameters through graphs and tables. The combined effect of the magnetic field and couple stress is significant on bearing characteristics. It is noticed that the bearing features increase with the longitudinal roughness parameter, and the reverse phenomenon is observed with the transverse roughness parameter. When a transverse roughness pattern is assumed on a secant slider bearing, characteristics like pressure, load, stiffness of the film, and damping coefficient increase significantly. [ABSTRACT FROM AUTHOR]

The primary intent of this paper is to examine the influence of radiation, Soret, and Dufour on the laminar flow of a rotating fluid through a permeable plate undergoing a chemical reaction. The Soret effect, for example, has been employed to differentiate isotopes and to combine gases of different molecular weights. Many real-world applications, including geosciences and chemical engineering, comprise the Soret and Dufour effects. Using similarity variables, the governing equations and allied boundary conditions (BCs) are simplified to a dimensionless form and then solved using the finite element method (FEM). In order to get the numerical approximations of velocity, temperature, and concentration, dimensionless parameters of the flow were utilized, and the consequences were envisioned visually. The most significant results of this research are that raising the Soret and Dufour parameters causes an upsurge in the velocity profile and enhancing the radiation factor causes an upsurge in the temperature distribution. Enhancing the values of permeability causes a reduction in skin friction. Enhancing the accuracy of heat absorption factor estimations leads to an increase in the values of the Nusselt number. A comparison case study has been made among the outcomes of well-existing repository literature with the current solutions and detected a great correlation. [ABSTRACT FROM AUTHOR]

The primary aim of this paper is to investigate the dynamic behavior of generalized nonlinear fractional Tzitzéica-type equations and to derive optical soliton solutions. To achieve this goal, we employ the modified Khater method, focusing on obtaining solitary wave solutions for generalized fractional Tzitzéica-type (TT) equations. Through this approach, we unveil novel solutions for both Tzitzéica and Tzitzéica–Dodd–Bullough (TDB) equations expressed in terms of fractional derivatives. The significance of employing the modified Khater method lies in its ability to yield a diverse array of soliton solutions. These solutions encompass dark, bright, singular, periodic, kink, singular kink, and combined dark–bright solitons. The derived solutions are visually represented through two-dimensional (2D) and three-dimensional (3D) graphs. Our findings underscore that the proposed method serves as a comprehensive and efficient approach to explore exact solitary wave solutions for generalized fractional TT evolution equations. By employing the modified Khater method, we not only enhance our understanding of the dynamic behavior of these equations, but also provide a versatile tool for obtaining precise soliton solutions in the realm of nonlinear fractional evolution equations. [ABSTRACT FROM AUTHOR]

In this paper, we address various optical soliton solutions and demonstrate the different dynamics of solitary waves to a (3+1)-dimensional nonlinear Schrödinger equation (NLSE) with parabolic law (NLSE) using a newly created powerful and effective method named as the extended generalized Riccati equation mapping method. This technique presents an organized manner to reveal the essential dynamics. There is great significance of the nonlinear Schrödinger equations and their several formulations in numerous fields of science, particularly in nonlinear optics, optical fibers, quantum electronics, and plasma physics. Through the use of numerical simulations and mathematical analysis, we explore the characteristics and behavior of these solitary wave solutions in a variety of scientific contexts. These results demonstrate the essential complexity of the governing equation and yield novel derived solutions. These solutions contribute to a better understanding of nonlinear wave phenomena by highlighting the fundamental dynamics establishing solitary waves in the NLSE. To enhance our wider knowledge, we provide effective graphic representations of the nonlinear wave structures in the derived solutions utilizing a variety of graphs, including 3D, 2D, and density plots. Moreover, a specific transformation has been applied to transform the system into a planar dynamical system, and several phase portraits have been presented to examine its behavior. Furthermore, upon introducing a perturbed term, chaotic behavior has been observed across different parameter values through both two-dimensional and three-dimensional graphics. [ABSTRACT FROM AUTHOR]

Noise pollution is growing nowadays and there is always a conflict between ventilation and noise insulation. The advances in acoustic metamaterials provide an effective solution for this conflict. In this paper, we propose a metastructure with protruded necks based on Helmholtz resonance. Sound transmission loss (STL) of 13 dB at low-frequency of 488 Hz is obtained in experiment with the ventilation of 20%, which is in good agreement with the simulation. It is revealed that introduction of protruded neck can reduce the resonant frequency. Sound absorption is the main mechanism for noise insulation at low frequency. Next, the effects of geometric parameters on sound insulation are discussed. A reduction in cross-sectional area of neck, an increase in neck length, and an increase in ventilation all lead to a decrease in both resonant frequencies and STL amplitudes. Finally, a two-layer structure is constructed by the proposed metastructure with different neck length in each unit. Both the amplitude and frequency range of STL are enlarged. These results exhibit a practical application for ventilated metastructure in sound insulation at low frequency. [ABSTRACT FROM AUTHOR]

Quantum orthogonal arrays are combinatorial designs with a remarkable class of genuinely multipartite highly entangled states. In this paper, we propose the method for constructing maximally multi-qubit entangled state through phase parameters of orthogonal arrays. Using this method, we not only determine that maximally n-qubit entangled state, but also find the n − 1 orthogonal array that gives maximally n − 1 entangled states. Such states play an important role in quantum theory with a high degree of multipartite entanglement. [ABSTRACT FROM AUTHOR]

The motivation of this paper is to explore an oscillatory flow of a magnetohydrodynamics (MHD) couple stress fluid with heat and mass transfer analyses through a porous medium. The modified Darcy–Brinkman couple stress fluid model is employed. There could be many potential applications of this study, such as thermal system, solidification of liquid crystals, cooling of metallic plates in a bath, exotic lubricants and colloidal solutions. In the wake of these potential applications, the study of MHD couple stress fluid flow with additional diffusing components has been found to be innovative and very interesting in the analysis of the influence of combined magnetic effects, couple stress fluid and two solutes. A governing coupled nonlinear partial differential equation with boundary constraints represents the modeled flow problem. In addition, these equations are converted into nondimensional form by employing the suitable nondimensionalizing quantities. It is possible to attain analytic solutions to the dimensionless equations that control the liquid flow, and the consequences of the flow's confines on velocity, temperature, concentration and skin friction profile are examined and also the results are discussed through graphs. It is noteworthy that when the injection level on the heated plate is increased, the skin friction on each channel plate also increases. [ABSTRACT FROM AUTHOR]

Aiming at the problem of low quality of coherent demodulation transmission signal of digital signal in the background of Levy noise, this paper proposes a new method of 4FSK signal reception based on adaptive tristable stochastic resonance (SR) system. The bit error rate (BER) of output signals of adaptive tristable SR system model and the traditional modulation model are compared by simulation. The numerical simulation results show that compared with the traditional model, the output BER of the 4FSK signal after demodulation of the adaptive tristable SR system model is reduced by 4% compared with the traditional model. The time domain image of 4FSK signal is clearer, the burrs are significantly reduced and the spectral amplitude of 4FSK signal is greatly improved. The success of this experiment suggests a strong promise of SR systems for digital signal detection in impact noise. [ABSTRACT FROM AUTHOR]

In this paper, we will investigate the structural, electronic, mechanical, magnetic and optical properties of Heusler Mn2NiAl (MNA) compound using the Perdew–Burke–Ernzerhof generalized gradient approximation (PBE-GGA) of the full potential linearized augmented plane-wave method for exchange and use correlations, modified Becke–Johnson and GGA+U Hubbard parameter. The calculated band structure (BS) and density of states (DOS) of MNA showed a metallic (GGA), nearly half-metallic (mBJ) and half metallic (GGA+U) behavior. Moreover, the magnetic computed magnetic moments by GGA+U are higher compared to GGA and mBJ results. Bulk modulus, shear modulus, Voigt and Reuss polycrystalline elastic modulus, Debye temperature, sound velocities, the melting temperatures, B / G ratio, Young's modulus and Poisson's ratio were obtained. The elastic anisotropy of MNA alloy was analyzed using 2D and 3D figures of directional dependence of Poisson's ratio, shear modulus, linear compressibility and Young's modulus. Studies have shown that the Heusler material MNA has magnetic and anisotropic properties and is mechanically stable. [ABSTRACT FROM AUTHOR]

With the rapid development of electronics, the application and research of two-dimensional materials have been at the forefront of the world's scientific research. Black phosphorus (BP) has the advantages of large specific surface area, anisotropy, band tunability, high electrical conductivity and high theoretical specific capacity, which make it very promising for research in the fields of medicine, aerospace and electrochemistry. This paper calculates the electronic structure and adsorption properties of BP in water for different heavy metal ions of Pb 2 + , Hg 2 + and Cd 2 + , including adsorption energy, bandgap, electron density and Mulliken population analysis, based on the first-principles approach of density generalized theory. First principles are quantum mechanical calculations based on density functional theory (DFT), which is a dominant well-developed method in the field of materials simulations, with low errors and high efficiency, especially in systems containing metallic particles. The results showed that the Pb 2 + adsorption system in water was more stable than the Hg 2 + adsorption system and the Cd 2 + adsorption system. The bandgap values of 0.617, 0.785 and 0.715 eV of BP after adsorption of Pb 2 + , Hg 2 + and Cd 2 + in water are smaller compared to 0.891 eV of intrinsic BP, and its properties change from direct bandgap semiconductor to indirect bandgap semiconductor. The higher the stability of a system for the adsorption of different heavy metal ions by BP, the higher the internal electron activity of the adsorption system and the amount of electron transfer. Meanwhile, it is concluded that the electrons mainly transfer from P to heavy metal ions in all the adsorption systems. The electron transfer of the BP-Pb 2 + , Hg 2 + , and Cd 2 + adsorption system occurs mainly in the p, s, and s/p orbitals, respectively. The above content investigated the electronic structure changes and internal electron transfer of heavy metal ions adsorbed by black phosphorus in water, expecting to provide a new reference basis for the detection of heavy metal ions in industrial wastewater using black phosphorus. [ABSTRACT FROM AUTHOR]

In this paper, the motion of inertial particles in three-dimensional (3D) unsteady cylindrical wake flow is investigated by a two-way coupled Eulerian–Lagrangian approach. At different flow Reynolds numbers (Re), the corresponding striking dynamic property and dispersion mechanism of four particle classes have been studied, with inertia parameterized by means of Stokes number (Sk). It is found that inertial particles with lower Stokes number are expelled from vortex cores, and coherent voids encompass the local Kármán vortex cells. As Stokes number increases, a low velocity particle channel could be formed, which almost coincides with the results in the literature. Moreover, with the increase of Reynolds number, numerous irregular coherent voids are observed in the cylinder wake, and the high-speed particles follow the fluid flow closely when they are contained in the vortices. Although the centrifugal force of Kármán vortex cells significantly affects the dynamics of inertial particles, the fluid flow modulation is believed to be responsible for the distinctive particle dispersion patterns in the vortex streets. For particles with medium inertia, the two-way coupled modulation weakens the centrifugal effect of vortex structures on the particles. This trend declines with the increase of Reynolds number, and vanishes with light particles, while both two-way coupled modulation and the centrifugal effect of vortex structures are almost equally effective with heavy particles. The investigations contribute to a better understanding of the particle-laden flows in practical applications, which will benefit the optimized design of certain machinery and equipment for the industry. [ABSTRACT FROM AUTHOR]

The present boundary layer flow of Maxwell fluid over a stretching sheet has good number of practical applications in metallurgy, drawing of plastics, polymer sheet extrusion including hot rolling extrusion, glass blowing, spinning of fibers, rubber and plastic sheets, crystal growing and many more. Due to these extensive applications of Maxwell fluid in engineering, medicine and manufacturing industries including the above-mentioned applications, authors have motived, inspired and investigated the present problem. However, in this research paper, the influences of Soret and Dufour effects on the steady-state Maxwell fluid flow past a stretching sheet with nonuniform heat source/sink are considered numerically. The thermal and concentration stratifications impacts are also incorporated. The viscous dissipation and magnetic field effects are also included in the respective governing equations. The main novelty and uniqueness of this numerical research is to generalize the earlier studies and describe the salient features of magneto-thermo visco-elastic dissipative Maxwell fluid motion about a stretching sheet with cross-diffusion effects under the influence of double stratification phenomena. To differentiate the non-Newtonian fluids from those of Newtonian fluids, a well-known Maxwell fluid flow model is used in the present study. The investigated physical problem results the highly nonlinear coupled partial differential equations (PDEs) and which are not amenable to any of the direct methods. Suitable similarity transformations are deployed to reduce the highly complex PDEs into the system of ordinary differential equations (ODEs). A robust BVP4C Matlab function is employed to solve the rendered dimensionless system of ODEs. The numerically generated computed data is plotted in terms of velocity, temperature and concentration profiles including engineering quantities of interest such as skin-friction, Nusselt and Sherwood numbers in the flow region. It is evident from the current analysis that, the amplified magnetic field decreases the velocity field and increases the thermal and concentration distribution fields. Accelerating Maxwell’s number diminished the flow velocity and increased the temperature field. Increasing Soret and Dufour numbers enhances the concentration and temperature fields, respectively. Amplifying Maxwell’s number raises the skin-friction coefficient and enlarging the thermal stratification parameter magnifies the thermal transport rate. The mass transport rate amplified with a raise in concentration stratification number in the flow region. Finally, it is provided that, the current results are excellently matching with earlier published results in the literature and it confirms the accuracy of the used numerical method and the produced similarity solutions. [ABSTRACT FROM AUTHOR]

The objective of this paper is to examine the analytical properties of the nonlinear (1+1)-dimensional Camassa–Holm equation (ℂℍ), a fundamental model within the domain of nonlinear evolution equations. The aforementioned equation serves as a valuable tool in elucidating the unidirectional propagation of shallow water waves over a level terrain, as well as in representing certain nonlinear wave phenomena seen in cylindrical hyperelastic rods. We use the Khater III (핂hat.III) and improved Kudryashov (핀핂ud) technique to provide accurate solutions, drawing inspiration from the intricate mathematical framework of the ℂℍ issue. He’s variational iteration (ℍ핍핀) technique is used as a numerical methodology to assess the correctness of the generated answers. This strategy reveals a notable concurrence between the analytical and numerical outcomes. This alignment guarantees the suitability of the acquired solutions within the framework of the studied model.The importance of this investigation lies in its ability to improve our comprehension of the intricate dynamics regulated by the ℂℍ equation and its connections with other nonlinear evolution equations that describe shallow water wave behaviors and nonlinear wave propagation in cylindrical hyperelastic rods. The results of the study demonstrate novel analytical approaches, expanding the range of potential solutions and offering valuable insights into the physical characteristics of the interconnected wave phenomena. This research offers valuable insights and methodologies for addressing intricate mathematical models in shallow water wave theory and studying nonlinear waves in hyperelastic materials, therefore making substantial advances to the subject of nonlinear partial differential equations. [ABSTRACT FROM AUTHOR]

This paper inspects the combined effects of heat and mass transfers in a hybridized Williamson viscous nanofluid composed of cadmium telluride (CdTe) and silicon carbide (SiC) nanoparticles in RT42 (Rubitherm) as base fluid in the existence of heat source and thermal radiative aspects. Knowing that the base fluid RT42 is a phase change material (PCM), it is also considered that the surface on which the nanofluid flows is an expandable surface with varying thickness. The influence of chemical reactions process and viscous dissipation on the flow and temperature of the hybridized nanofluid is examined. The parameters’ influences on the problem are evaluated after setting appropriate similarity transformations to transform the collection of major partial differential equations (PDEs) into nondimensional ordinary differential equations (ODEs). The study concludes that the presence of hybridized nanoparticles of CdTe and SiC reduces the horizontal and vertical surface frictional forces of the hybrid nanofluid. The integration of nanoparticles in RT42 enhances heat transfer rates and reduces mass transfer. The thermal radiative variable declines the heat transfer of hybridized nanofluid. The results indicate that altering the variable parameter of surface thickness reduces frictional forces in both directions. [ABSTRACT FROM AUTHOR]

In this paper, we construct the photonic dam-break flow problem for ϕ(α) magnetic fluid in a spherical model. Then, we obtain an optical magnetic transform for the NLSE in hydrodynamical form. By dispersive photonic hydrodynamic representation, normal of surface ϕ(α) flow is obtained. Thus, we design two-phase ϕ(α) flow dispersion density in a spherical model. Finally, we have new modeling of dispersive dam break two-phase ϕ(α) flux. [ABSTRACT FROM AUTHOR]

The study is accomplished to explore the pioneering of a two-dimensional ferromagnetic fluid flow over a flat elastic sheet with the magnetic dipole effect. The recent flow design was selected as it is mostly applicable in bioengineering as well as engineering fields that includes magnetic drug targeting systems. In this paper, the impacts of thermal radiation and magnetic dipole in flow of ferromagnetic Sutterby fluid for a stretching surface are examined. Some suitable similarity transformations are exploited to achieve the system of nonlinear ODEs from set of PDEs, then acquired ODEs are resolved by numerical scheme known as bvp4c technique. Impacts of ferromagnetic interaction parameter, viscous dissipation and curie temperature are perceived for velocity as well as temperature fields. Furthermore, velocity as well as thermal gradients are deliberated and scrutinized pictorially. [ABSTRACT FROM AUTHOR]

In this paper, under the observation of extended modified rational expansion method based on symbolic computation, the multiple solitary wave solutions for nonlinear two-dimensional Jaulent–Miodek Hierarchy (JMH) equation are constructed. In this investigation, we use the computer software Mathematica for the construction of multiple solitary wave solutions. The interested and important things in this work are the multiple solitary wave solutions which have various kinds of physical structures such as kink soliton, periodic traveling wave, bright soliton, anti-kink soliton, dark soliton, combined bright and dark solitons, topological soliton and peakon soliton. We are sure that the various kinds of soliton solutions are found first time by using one method in the existing literature works. On the basis of this research, we can say that the applied technique is very efficient, reliable, fruitful and powerful. The constructed soliton solutions for nonlinear JMH equation will play an important role in the investigation of different physical phenomena in nonlinear sciences. [ABSTRACT FROM AUTHOR]

The steam condenser is a crucial component in power plants, playing a vital role in influencing the overall performance of steam power plants. This paper delves into a detailed assessment of the thermal aspects and evaluation of steam surface condensers. To conduct this rigorous evaluation, we meticulously crafted a three-dimensional (3D) model of a multi-tube single-pass counter-flow heat exchanger using ANSYS Design-Modeller. Within this model, a multiphase mixture model was harnessed to replicate the condensation process that takes place within the condenser. After the model's development, a series of computational fluid dynamics (CFD) simulations were expertly executed utilizing ANSYS Fluent Workbench. The simulations encompassed diverse cooling water flow rates and steam inlet velocities. Notably, two sets of CFD simulations were carried out: the initial set featured a velocity inlet in the condenser, while the second set involved CFD simulations with a pressure steam inlet. The findings derived from these simulations unveiled a noteworthy correlation between the condensation rate within the shell and both the rate of circulating water flow and the operational pressure of the condenser. Additionally, it was discerned that the condensation rate could be further influenced by the specific geometry of the condenser. In sum, this study concludes that optimizing the geometrical configuration and baffle arrangements holds promise for increasing the condensation rate and overall performance of steam condensers employed within steam power plants. [ABSTRACT FROM AUTHOR]

In order to grasp the playing functions that utilize criteria for decision-making (DM) approaches, this paper offers a League season learning selection issue. The decision criteria to assess several game-based learning options are outlined, and a real-world choice dilemma is provided. Finding the most effective League season learning among playing functions is the goal. The needs for a League season of learning, such as Cognitive Methodologies, Gameplay Characteristics, Psychological Reactions, Accessibility, Users, as well as its environmental and societal impacts, are taken into consideration, leading to the identification of six primary criteria and 22 sub-criteria. Analytical Hierarchy Process (AHP) is used to calculate the criterion weights. The Preference Ranking Organization Method for Enrichment Evaluations and Vlse Kriterijumska Optimizacija I Kompromisno Resenje techniques are used to rank and choose between four possibilities. The outcomes of the Preference Ranking Organization Method for Enrichment Evaluations and Vlse Kriterijumska Optimizacija I Kompromisno Resenje procedures are also contrasted with those of the Complex Proportional Assessment, Multi-Atributive Ideal-Real Comparative Analysis and Multi-Attributive Border Approximation Area Comparison approaches. The results of the rankings of the alternatives produced by each approach all recommend the same choice as the best. Thus, it can be said that Preference Ranking Organization Method for Enrichment Evaluations, Vlse Kriterijumska Optimizacija I Kompromisno Resenje, Complex Proportional Assessment, Multi-Atributive Ideal-Real Comparative Analysis and Multi-Attributive Border Approximation Area Comparison approaches may be successfully employed for selection issues in game-based learning, as well as generally for other forms of multi-criteria decision problems with finite number of choices. [ABSTRACT FROM AUTHOR]

In this study, K2Ti6O13 (KTO) nanowires were doped with carbon (CKTO) via a novel solid-phase approach at 800∘C for the first time using ethanol, KF, and TiO2. In addition to the lower sintering temperature, a shorter insulation period was achieved compared to the conventional solid-phase method. Furthermore, by combining and calcining CKTO and g-C3N4, a CKTO/g-C3N4 heterojunction composite was produced. The rate at which CKTO/g-C3N4 photocatalytically degraded methylene blue was higher than those of pure CKTO and g-C3N4. Our study indicates that adding g-C3N4 enhances photocatalytic performance by reducing the recombination rate of photogenerated electron–hole pairs and narrowing the bandgap of the CKTO/g-C3N4 heterostructure. This paper presents a novel method for creating KTO composites in an eco-friendly and productive manner for the photocatalytic degradation of organic colors. [ABSTRACT FROM AUTHOR]

In the food industry, electrical conductivity is essential for heating processes. The dependence on temperature conductivity of electricity on the outermost layers flow of the nanofluid is the main topic of this paper. Variable electrical conductivity, viscosity, thermo diffusion, thermal radiation and radiation absorption on convective heat and mass transfer flow Cuo and Al2O3-water nano-fluids confined in cylindrical annulus. The non-linear governing equations have been solved by finite element technique with quadratic approximation functions. For various parametric adjustments, the temperature, speed, and nanoconcentration have all been examined. Similar to the cylindrical wall, quantitative evaluations have been made of the surface resistance, temperature rate and mass transport. It is discovered that for both types of nanofluids, a higher thermo-diffusion effect leads to a lower concentration and Sherwood digits on the cylinders. An augment in Q1 enriches the rapidity in CuO-water nanofluidic system as well as decreases in Al2O3-water nanofluidic. Increased Q1 lowers the real temperature and nanoconcentration in both types of nanofluids. [ABSTRACT FROM AUTHOR]

Membrane-type acoustic metamaterials have a favorable noise suppression effect. Hence, a membrane-type acoustic metamaterial plate (MAML) with an X-shaped pendulum arm and cylindrical mass blocks (CMB) was proposed in this paper. The theoretical model based on spring–mass systems and numerical simulation models of the membrane-type acoustic metamaterial cell (MAMC) were established under fixed and periodic boundary conditions to reveal the noise attenuation mechanism quantitatively, and the necessity of the CMB is discussed. Based on the results, it can be observed that the normal displacement of the membrane is nearly zero when the noise frequency is at the peak of the sound transmission loss (STL) curve. However, when the frequency is at the valley of the STL curve, the displacement is nonzero and fluctuates significantly. Meanwhile, by comparing the STL curves with and without the CMB, it was found that the MAMC performance is improved effectively by the CMB at low frequencies. The effective mass density of MAMC was found to be negative. To verify the accuracy of numerical calculations, an impedance tube experiment was conducted. Finally, orthogonal experiments were designed to describe the effects of the structural parameters a, l, and t on the effective bandwidth Ω, peak frequency Φ, and comprehensive index ξ and to obtain the optimal structural parameter combinations for different indexes. This work further contributes to applying and developing the membrane-type acoustic metamaterial. [ABSTRACT FROM AUTHOR]

The Fordy–Gibbons equation is a nonlinear differential equation. Physically, the motion of a damped oscillator with a more complex potential than in basic harmonic motion is described by the Fordy–Gibbons equation. For the equation under consideration, numerous novel families of precise analytical solutions are being successfully found. The soliton solutions are represented as rational and exponential functions. To further illustrate the potential and physical behavior of the equation, the findings are also stated visually. Three approaches are suggested in this paper for solving the Fordy–Gibbons equation. These solutions are new solutions. [ABSTRACT FROM AUTHOR]

Due to the distinctive working environment of high precision machining and manufacturing field, it poses challenges in meeting the isolation requirements, including limited installation space, multi-dimensional vibration, and a wide range of vibration frequencies. To tackle these obstacles, this paper introduces a magnetorheological (MR) isolator that offers adjustable vertical damping characteristics while guaranteeing three-axis vibration isolation through an inclined cone structure. First, the structure of the isolator was designed by combining a flow valve damper with a conical rubber structure. Second, in pursuit of lightweight design and enhanced magnetic field strength, collaborative simulations using ANSYS and Maxwell are conducted to subject the critical components of the isolator to multi-objective optimization. The optimization results demonstrate that the mass of the isolator has been reduced by approximately 27.7%, while the magnetic field intensity has increased by around 20%. Finally, the performance of the MR isolator was verified through static testing and dynamic testing, respectively. The experimental results demonstrate that the isolator can generate a maximum damping force of approximately 778N when exposed to a current of 1.5A. Compared to the initial value of 445.06N at 0A, there has been an approximate increase of 1.74 times. [ABSTRACT FROM AUTHOR]

Research on the improvement of the photoelectric conversion efficiency of solar cells is always the focus. In this paper, an efficient anti-reflection micro/nanostructure is proposed to improve the conversion efficiency of the solar cell. Graded effective refractive index theory is used to achieve the anti-reflection effect while the simulation model is established by FDTD. A specific periodic nanostructure is obtained, which can achieve a good anti-reflection effect. According to the simulation model, the reflectivity of the solar cell is reduced by 0.85% and the transmittance is increased by 0.85% in the band range of 200 nm to 1000 nm. Specifically, high anti-reflection phenomena are obtained in the band range of ultraviolet and blue light, in which the reflectivity is reduced by 1.56% and the transmittance is increased by 1.55%. Based on the simulation results, the array nanostructure is produced by etching the self-assembled polystyrene (PS) microspheres. Finally, the required structure is formed on the silicon wafer by nanoimprinting and etching technology. The reflectivity of 2.8% is obtained on silicon, which can potentially increase the opto-electrical performance of the solar cell. [ABSTRACT FROM AUTHOR]

In this paper, the computational examination is carried out on the heat generation, Soret and Dufour’s influence on the unsteady MHD convection flow of an incompressible viscous fluid with chemical reaction. It is due to the exponentially accelerated vertical porous plate embedded in a permeable medium with ramped wall temperature together with surface concentration and also with thermal radiation impacts. The basic governing set of the equations of the fluid dynamics to the flow is converted into nondimensional form by inserting suitable nondimensional parameters and variables. In addition, the resultant equations are solved computationally with the efficient Crank–Nicolsons implicit finite difference methodology. The influences for several imperative substantial parameters for the model on the velocity, temperature and concentration for the fluids, the skin friction coefficient, Nusselt and Sherwood number for together thermal situations have been explored with the help of graphical profiles and tabular forms. It is found that, the increasing quantities of the Dufour, temperature generation and thermal radiation parameters, the fluid temperature as well as velocity enhances. Similarly, it is noted that an escalating Soret parameter causes the fluid’s velocity and concentration whereas the chemical reaction parameter notifies reversal outputs. [ABSTRACT FROM AUTHOR]

A novel 3D chaotic oscillator that incorporates quadratic and absolute-function nonlinearities is introduced in this paper. The system dynamics are explored using the Lyapunov direct method, phase plane trajectories, time response, Lyapunov exponents, bifurcation diagrams, and basins of attraction. The uniqueness and existence of the system solution have been proven. The analytical investigations show that the system has two stable equilibrium points along with one unstable equilibrium point and a line of equilibria. The positive half of this line represents unstable equilibria, while the negative half is associated with stable equilibria. Additionally, it is found that the oscillator exhibits a chaotic basin of attraction centered along the line of equilibria and surrounded by a fixed-point attractor. An electronic circuit using Multisim software is designed to demonstrate the possibility of physical implementation for the considered mathematical model. Chaos control is addressed using adaptive and sliding mode control strategies. The performance of both control methods is compared, with the sliding mode control demonstrating superior results in both fast response and small transient overshoot. Furthermore, a novel sliding mode controller for master–slave synchronization is introduced, showing high performance compared to other sliding-mode and adaptive control methods applied in the literature. Finally, the proposed oscillator is employed as a Pseudo Random Number Generator (PRNG) for image encryption applications using a new encryption model. The experimental results confirm the high security and robustness of the proposed encryption algorithm against various attack methods. [ABSTRACT FROM AUTHOR]

In this paper, alumina-reinforced copper-based composite materials were prepared by using the electroless plating method to coat copper powder with a layer of silver and then combining the solution sol method and powder metallurgy method. The results show that recrystallized structures and twins appear in composite materials after high-temperature sintering. As the sintering temperature increases, the ratio of recrystallized structures and twins gradually decreases, and straight coherent Σ3 annealing twins appear in the structure, the number of high-angle grain boundaries decreased, the number of small-angle grain boundaries continues to increase, the average grain size increased from 3.89 to 4.83μm, the tensile strength increased from 156MPa to 167.5MPa, the maximum elongation was 9.4%, and the density increased from 6.81g/cm3 increased to 7.62g/cm3, the porosity dropped from 13.3% to 5.5%, the conductivity increased from 60.3% IACS to 73.2% IACS, the maximum hardness value was 68.71 HV, the best performance of the composite was achieved by sintering at 900°C with the tensile strength and elongation are 163MPa and 9%, respectively, the conductivity is 68.9% IACS, and the density is 7.35g/cm3. Its fracture surface shows mostly ductile features. [ABSTRACT FROM AUTHOR]

Permanent magnet synchronous motor (PMSM) can exhibit chaotic behaviors detrimental to their regular operation in practical applications. To accurately predict the chaotic state of PMSM, this paper proposes a C-MRESN method based on the combination of convolutional neural network (CNN) and multi-reservoir echo state network (MRESN). The significant advantage of C-MRESN is that it combines the advantages of the two models, which can capture the complex temporal and spatial information from nonlinear time series and retain these features for prediction. In addition, this work uses the L-BFGS-B optimization algorithm to optimize the training process of C-MRESN and significantly improve the prediction accuracy of C-MRESN. By comparing the prediction experimental results with six other machine learning models, C-MRESN shows the minor prediction error and the most extended accurate prediction range. The root mean square error (MSE) of the 2000-step prediction results of C-MRESN for the three PMSM variables, id,iq and ω can reach 1.190×10−9, 8.599×10−10 and 1.626×10−9, respectively. The experimental results substantiate that the C-MRESN is an effective and advanced method for the chaos prediction of PMSM. [ABSTRACT FROM AUTHOR]

In this paper, we investigate the heat transfer characteristics of magnetohydrodynamics (MHD) with Williamson hybrid nanofluid (HNF), considering the influence of bioconvection as well as a chemical reaction on a stretched surface. We observe no investigation on bioconvection Williamson HNFs flow in the literature, which is a novel contribution to the literature. The recent study seeks to enhance the heat transfer rate by investigating inclined magnetic field, along with the interplay of bioconvection and chemical reactions. The employed hybrid nanoparticles consist of titanium dioxide (TiO2) and copper (Cu) suspended in base fluid (water). The governing partial differential equations (PDEs) are changed into nonlinear ordinary differential equations (ODEs) through an appropriate similarity transformation. These ODEs are subsequently analyzed employing the MATLAB bvp4c approach numerically. This study presents comprehensive insights into the behavior of distinct parameters, conveyed through phase portraits of temperature, velocity, nanoparticle concentration, as well as microorganism density profiles. The results showed that the momentum profile was inversely affected by increasing Williamson parameter, magnetic force, and inclination angle, while the temperature was boosted with advanced magnetic field, radiation parameter as well as Brownian motion parameter values. [ABSTRACT FROM AUTHOR]

This paper aims to theoretically examine the phenomenon of modulation instability (MI) in the presence of a considerable nonlinear refractive index movement in a triad-core nonlinear coupler, including a bi-negative refractive material transmission medium. The formula for the instability gain is deduced with the help of the linear stability analysis. The significant role of cubic, quintic, septic, nonic, and stability of the front-to-reverse-transmitting wave nonlinearities in the phenomenon of MI in the nonlinear triad-core coupler is critically confirmed via MI gain spectra analysis. It is found that the cubic, quintic, septic, and nonic nonlinearities improve the MI in both dispersion regimes (normal and anomalous) by boosting the gain and width of the instability profile by taking account of reverse-to-front ratio power (f). On the other hand, quintic nonlinearity improves the MI in the cubic case by enhancing its width and gain in the normal and anomalous dispersion areas. Using 3D pictures, we analyze the dynamic behavior of the MI under an anomalous dispersion area and find that, in both normal and anomalous dispersion scenarios, the instability shape develops with septic and nonic nonlinearity. Furthermore, as the figures clearly show, neither the normal nor the anomalous dispersion scenario significantly changes due to septic and nonic nonlinearity alone. We aim to shed light on the role of contamination in saturation nonlinearity by examining soliton and MI, their production, and control in triad-core couplers, focusing on a Negative Index Meta Material (NIMM) transmission medium. [ABSTRACT FROM AUTHOR]

The objective of this paper is to analyze the unsteady incompressible flow of the viscous nanofluid on a contracting surface with viscous dissipation effects. Presented and contrasted are analyses of both multi-wall carbon nanotubes (MWNTs) and single-wall carbon nanotubes (SWNTs). As the common (or base) fluids, kerosene oil and water are utilized. In the existence of first-order thermal and velocity slip conditions, mathematical modeling and analysis are performed. Using the MATLAB software's bvp4c solver tool, numerical solutions to the governing nonlinear modeled problems were obtained. This technique is particularly effective for developing many solutions to highly nonlinear differential equations. In addition, a comparison is done between this study and previously published works. The temperature, velocity, skin friction coefficient and heat-transfer rate have been explored for various significant factors included in the problem statements. In the unsteadiness parameter regime, dual solutions can be found. As the velocity slip parameter is increased, the flow slows down. In comparison to SWCNTs kerosene, MWCNTs kerosene oil has a greater velocity curve for the nanoparticles volume fraction. Increases in volume fraction decrease skin friction, whereas increases in the unsteadiness parameter speed up the drag force. Furthermore, as the Eckert number intensity increases, so do the temperature profiles in both solutions. Finally, the stability study revealed that the initial solution is robust, whereas the breakage in the second solution in the Nusselt number shows singularity, and thus the second solution is considered unstable. [ABSTRACT FROM AUTHOR]

This research explores the dual-mode manifestation within the nonlinear Schrödinger equation, elucidating the amplification or absorption of paired waves. This study delves into the simultaneous generation of two distinct waves associated with the dual-mode phenomenon with three crucial parameters: phase velocity, nonlinearity and dispersive factor. The resulting wave phenomena from these solutions have implications across various fields, including fluid dynamics, water wave mechanics, ocean engineering and scientific inquiry. The study employs the modified Sardar sub-equation method to obtain the optical soliton solutions, encompassing various types such as dark, bright, singular, combo dark–singular, periodic singular and dark–bright solitons. The obtained results highlight the reliability and simplicity of the modified Sardar sub-equation method. Additionally, the paper delves into the parametric conditions crucial for shaping and sustaining these solitons. The research explores the interaction of dual waves and the variation in wave speed. Furthermore, dynamic phenomena are illustrated, and the physical implications of the solutions are interpreted using 3D and 2D plots with different parameter values. [ABSTRACT FROM AUTHOR]

Marine propellers operate under severe service conditions and experience various corrosion forms. Electrochemical, mechanical, and biological corrosion are the three main common types of corrosion that occur on marine propellers. Electrolysis (electrolytic corrosion), being one of the electrochemical corrosion forms, has been extensively observed on marine propellers. It is the forced introduction of an external current in metals when submerged in seawater. However, it has rarely been studied for marine propellers, mostly on underground pipelines. This paper investigates the effect of electrolysis on a chromium-containing coating on copper substrate by studying the surface and cross-sectional microstructure of the substrate. It is likely that cathodic disbondment caused by high alkalinity and hydrogen evolution at the defect location were the primary reasons contributing to the failure of the coating, and the silver-colored layer deposition around the delaminated area is the corrosion product of copper–chromium oxide. The purpose of this study is to understand the electrolysis corrosion mechanism on Cu substrate and to develop a highly effective anticorrosion coating for marine propellers. [ABSTRACT FROM AUTHOR]

Variational Integrator (VI) is a numerical technique, in which the Lagrangian of the system is used as the action integral. It is a special type of numerical solution that preserves the energy and momentum of the system. In this paper, we retrieve numerical solutions for heat and wave equation with the help of all possible combinations of finite difference scheme like forward–forward, forward–backward, forward–centered, backward–forward, backward–backward, backward–centered, centered–forward, centered–backward, centered–centered. We also use Lagrangian approach along with the projection technique to obtain approximate solutions of these linear models. This approach provides the best approximate solutions as well as preserves the energy of the system while the finite difference scheme gives only the numerical solutions. We also draw a comparison of existing exact solution with all approximate solutions for both models and provide graphical representation of these solutions. [ABSTRACT FROM AUTHOR]