International Journal of Modern Physics B

Link prediction is an important problem in complex network analysis, which can discover missing or possible future edges in the network. In recent years, link prediction methods based on network representation learning have made progress. But there are two problems with these methods. One is that neighborhood-based node sampling methods cannot handle the situation between two nodes that do not have any common neighbors. The other is the Skip-Gram-based embedding model that represents nodes as static vectors, which cannot reflect the various meanings of nodes. To overcome these two limitations, this paper proposes a method called AFS-BERT (Information entropy based Adaptive Fusion Sampling and BERT embedding model). First, this method defines a centrality score based on adjacency information entropy, which reflects the global and local importance of nodes. Second, we propose a sampling method that adaptively fuses two different strategies using the centrality score. Finally, the BERT-based embedding model is used to realize the low-dimensional dynamic vector representation of nodes. Experimental result on six real-world network datasets shows that AFS-BERT has better performance. Compared with methods of the same type, AFS-BERT achieves upto 6.7% improvement.

In this paper, numerical investigations have been performed on intricate double stratification impact with a radiative mixed convective nanofluid over a cylinder. Double stratifications comprise heat transfer used in many practical applications like power station engineering, ground-water reservoirs, thermal stratification of reservoirs, and rivers, density stratification of atmosphere, oceans, different heterogeneous mixtures, and manufacturing processing. Characteristics of heat and mass transfer have also been considered. The developing mathematical expression for momentum, energy transportation, and nano-concentration involving Brownian motion and thermophoresis inspiration are considered. The modeled equations are formulated into ordinary differential equations by applying a suitable similarity approach, which is then tackled numerically via MATLAB. Graphical illustrations of dimensionless velocity, energy, and volumetric concentration distribution are drawn against a few values of appropriate parameters. Results elucidate that enhancement occurs in the concentration profile, whereas decrement is noted for the temperature field for different values of thermophoresis and thermal stratification parameters. Our results elucidate good agreement as compared with the previously published one. The higher value of Hartmann number indicates a higher coefficient of friction.

This paper studies the Lax pair (LP) of the $(1+1)$-dimensional Benjamin–Bona–Mahony equation (BBBE). Based on the LP, initial solution and Darboux transformation (DT), the analytic one-soliton solution will also be obtained for BBBE. This paper contains a bunch of soliton solutions together with bright, dark, periodic, kink, rational, Weierstrass elliptic and Jacobi elliptic solutions for governing model through the newly developed sub-ODE method. The BBBE has a wide range of applications in modeling long surface gravity waves of small amplitude. In addition, we will evaluate generalized breathers, Akhmediev breathers and standard rogue wave solutions for stated model via appropriate ansatz schemes.

The description of superconductivity at high-temperature is a problem that has recently been addressed. Transition temperature of superconductivity, $T_c$, depends on the lattice structure type, size and room pressure. In super-lattices and low-dimensional layered nanostructures, $T_c$ is increased by increasing the complexity of the structure and internal pressures in solid lattice. In this paper, we investigate the relation between physical parameters ($ϵ,\mu$) of matter and superconductivity properties as well as transition temperature ($T_c$), and explain the superconductivity at high-temperature. In this study, a semi-classical electromagnetic description along with vortex topologic theory and quantum dynamic models with experimental data is considered to justify the relation between superconductivity phenomena and magnetic monopole properties. We find that the electromagnetic energy of magnetic monopole is in agreement with vortex energy in topological theory and it can get close to thermal energy at high-temperature. These models suggest that the superconductivity is related to the mobile monopole or vortices. We show that the electrical permittivity ($ϵ$) and magnetic permeability ($\mu$) of matter have a key role in the superconductive properties.

In this paper, the effect of the Poynting vector force field on periodically forced neutrally buoyant spherical particles at low Reynolds numbers is studied numerically. The mathematical formulation of six nonlinear coupled integro–differential equations was obtained by modifying the Lovalenti and Brady formalism for the hydrodynamic force acting on a spherical particle. The governing equations were solved using an adaptive step size Runge–Kutta method by integrating the integral using the trapezoidal rule. The forces acting on the particle-provided phase space trajectories are similar to Jeffery’s orbits. The paper also discusses the possible outcomes of the rheology due to the Poynting vector on the periodically forced neutrally buoyant sparsely spaced non-interacting spherical particles in a fluid at low Reynolds numbers. The computed rheological parameters in this study are first normal stress difference, second normal stress difference, intrinsic pressure and relative viscosity. The study shows that the first normal stress difference is nearly zero and the second normal stress difference is nonzero indicating the dominance of the Poynting vector field over the magnetic field on the bulk stress of the fluid. The intrinsic pressure and the relative viscosity changed due to the stress caused by the electromagnetic force and periodic force on the spherical particles.

The purpose of this paper is to study the intrinsic mechanical contributions of poled piezoelectric ceramics under the three ferroelectric phases [tetragonal (4mm), rhombohedral (3m) and orthorhombic (mm2)]. The intrinsic elastic coefficients and spontaneous strains of saturated and unsaturated poling piezoelectric ceramics are analyzed and calculated by probability density functions of orientation (PDFOs) and Reuss or Voigt average, and the analytical results of the intrinsic mechanical properties of piezoelectric ceramics with the poling degree are obtained. In addition, this paper also calculates the Young’s modulus and shear modulus of barium titanate (BaTiO₃) piezoelectric ceramics by PDFO which are based on the Reuss, Voigt and Hill averages. Comparing them with the published theoretical calculation data shows that the results calculated by the finite element method under the saturated and unsaturated poling states are within the range of the results calculated by us using the three average theories through PDFO, and it shows the accuracy of calculation by PDFO.

The extension of nanoliquid obtained by adding nano-powder composite or various nanoparticles in regular liquid is term as hybrid nanofluid. Hybrid nanofluids are more potential materials that significantly uplift the thermophysical feature and capacity of heat transportation instead of single nanoparticle nanoliquid. Hence, the paramount interest of this paper is to model theoretically the flow of aqueous alumina–titania hybrid nanoliquid across a rotating channel. Temperature-based viscosity is addressed. This analysis further contributes the impact of heat source and dissipation phenomena. Additionally, two different shapes of nanoparticles, namely, bricks- and needle-shaped are included. Similarity variables dimensionless the governing problem. The obtained system is solved by employing Mathematica-based NDSolve approach. The impact of various embedded variables is elucidated graphically. The presence of hybrid nanocomposite greatly affects the temperature and Nusselt number than nanoparticles. Further outcomes declared that rotation and heat source variables significantly increase the thermal field for hybrid nanophase when compared with nanophase.

This study aims to analyze the two-dimensional incompressible, steady MHD-mixed convective nanofluid flow with homogenous–heterogeneous (hh) reaction and Cattaneo–Christov heat flux (CCHF) past a rotating cone. The uniqueness of the presented model is the consideration of the surface-catalyzed reaction while considering the hh reactions on the surface of the cone in the existence of a permeable medium. Owing to this supposition, the rate of reaction is provoked in the least possible time. Moreover, irreversibility analysis is also performed for the suggested mathematical model in the wake of the second law of thermodynamics. The impacts of slip conditions and heat sink/source are also assessed here. The numerical model of these governing equations is solved using the MATLAB bvp4c package that addresses the system of ODES extracted from the governing PDEs. Graphs are used to evaluate the important consequences of the main arising parameters versus the concerned fields. The results revealed that in the presence of a high magnetic field, the temperature is enhanced. Moreover, the Entropy generation is boosted for magnetic and diffusion parameters. The results presented for this model are also corroborated by associating them with the published study.

A zinc oxide–silver doped with graphite and nitrogen (ZnO/Ag doped with C/N) heterostructure was prepared by a simple method with a study of the photodegradation of methylene blue (MB) dye under sunlight irradiation. Results from X-ray diffraction (XRD) experiments show the presence of sharp peaks for ZnO, Ag, and C, with the wurtzite phase of ZnO. Energy-dispersive X-ray spectroscopy (EDX) results match the results of XRD and confirm the presence of Ag, Zn, C, O, and N. Field emission scanning electron microscope (FESEM) images confirm the presence of clusters of spherical nanoparticles (NPs). The optical properties results confirm the high-absorption ability in the visible area with an energy gap of 2.95eV. After 140min of exposure to sunlight radiation, the photocatalysis results show that the MB dye can be broken down very well by light.

An electrostatic lattice is composed of many micro-scale traps. It is a powerful tool for manipulating cold polar molecules on a chip with the help of the interaction between the dipole moment and the inhomogeneous electric field. To the best of our knowledge, the existing electrostatic lattice still suffers the nonadiabatic transition that will lead to the escape of molecules from the electrostatic trap. In the paper, we skillfully design the electrode structure to avoid the zero-field zone at the center of every single microtrap, and the nonadiabatic transitions can be prevented. First, we numerically calculate the distribution of the spatial electrostatic field. Then, the influences of voltages on the electric field intensity and the height of the trap center are investigated. We simulate of the trajectory of molecules using the Monte Carlo method and figure out the factors impacting the loading efficiency of our electrostatic lattice. At last, we discuss how the voltages and the loading positions affect the positional distribution of trapped molecules.