Modern Physics Letters B

Nonlinear waves are seen in nature, such as the water waves and plasma waves. Investigated in this paper is a (3 + 1)-dimensional B-type Kadomtsev–Petviashvili–Boussinesq equation. Based on the bilinear method, we get the rational solutions, which are different from the published ones, semi-rational solutions and breather-type kink soliton solutions. Through the rational solutions, we observe two types of waves: the lump waves and line rogue waves. The semi-rational solutions depict two types of interactions: (1) The fusion or fission between the lump wave and soliton; (2) The interaction between the line rogue wave and soliton. During the interaction between the line rogue wave and soliton, the line rogue wave evolves with three different shapes: the bright rogue waves, bright–dark rogue waves and dark rogue waves. Via the breather-type kink soliton solutions, we observe the breather-soliton mixture.

The properties of nanomaterials usually depend on their microstructures, the same material of different microstructures could be used for various applications. However, most devices could only synthesize a single microstructure, so it is meaningful that the different microstructures were synthesized by one method. In our study, electrospinning was applied to fabricate ZnO nanofibers and nanoparticles. In this approach, Zn(Ac)/PVP composite fibers of different component ratio were synthesized by electrospinning method which was subsequently calcined and formed ZnO nanofibers and nanoparticles. The microstructure, chemical composition and gas sensing were investigated with scanning electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy and WS-60A gas sensing measurement system. The synthesis mechanisms of ZnO nanofibers and nanoparticles were discussed in detail.

In this paper, we consider the Von Kármán swirling-flow problem, which is described by an ordinary equations system. The explicit asymptotic solutions are given by applying the homotopy renormalization method. Furthermore, the numerical simulations verify that our asymptotic solutions have high precision and the absolute errors are less than 0.03, which means that the results obtained are truly valid and can be used practically.

In this paper, the simplified linear superposition principle is presented and employed to handle two versions of the fifth-order KdV equations, called the (2+1)-dimensional Caudrey–Dodd–Gibbon (CDG) equation and the (3+1)-dimensional generalized Kadomtsev–Petviashvili (KP) equation, respectively. Two general forms of resonant multi-soliton solutions are formally obtained. The paper proceeds step-by-step with increasing detail about the derivation process. Firstly, illustrate the algorithms of the linear superposition principle which paves the way for solving the wave related numbers. Then, demonstrate its application that exposes the proposed approach provides enough freedom to construct resonant multi-soliton wave solutions. Finally, some graphical representations of obtained solutions are portrayed by taking some definite values to free parameters, which describe various versions of inelastic interactions of resonant multi-soliton waves. The associated propagations may be related to large variety of real physical phenomena.

The high-pressure melting curves of defective metals Ni, Pd and Pt with face-centered cubic structure have been studied up to 100 GPa by using the statistical moment method. Our melting theory is based on the absolute stability limit for crystalline state. The effects of pressure and vacancies on the melting properties of Ni, Pd and Pt have been considered. These obtained results are consistent with previous experiments and other theoretical calculations.

A new type of intelligent micro displacement materials, giant magnetostrictive materials (GMM), have a wide range of potential applications in the fields of micro vibrations. In this paper, a novel type of giant magnetostrictive actuator (GMA), mainly made by the giant magnetostrictive materials, is designed, and its inner structure and working principle are also discussed. To investigate the output force of giant magnetostrictive actuator, a test system, including the force sensor, data acquisition card and power supply equipment are established. The experimental results show, when the excited current increased from 0.5 A to 2 A gradually, the output force of the giant magnetostrictive actuator also gradually increased, in the condition of the pre-compress force from 100 N to 400 N, the output force of the giant magnetostrictive actuator will also increase with the increasing of the pre-compress force.

A two-step microreactor for the preparation of Diphenyldimethoxysilane $({({\mathrm{\text{C}}}_6{\mathrm{\text{H}}}_5)}_2\mathrm{\text{Si}}{({\mathrm{\text{OCH}}}_3)}_2)$ is established. Diphenyldichlorosilane $({({\mathrm{\text{C}}}_6{\mathrm{\text{H}}}_5)}_2{\mathrm{\text{SiCl}}}_2)$ and methanol $({\mathrm{\text{CH}}}_3\mathrm{\text{OH}})$ are selected as reactants. A model is created to optimize the structure of the reaction domain of the microreactor. The optimization parameters are $P=3:4$, $R=1:1$, $L=70\mu \mathrm{\text{m}}$. The concentration of the products is compared when there are obstacles in the reaction domains and non-reaction domains. The model and optimization method are helpful in the design of microreactor.

Machine learning (ML) represents the automated extraction of models (or patterns) from data. All ML techniques start with data. These data describe the desired relationship between the ML model inputs and outputs, the latter of which may be implicit for unsupervised approaches. Equivalently, these data encode the requirements we wish to be embodied in our ML model. Thereafter, the model selection comes in action, to select an efficient ML model. In this paper, we have focused on various ML models which are the extensions of the well-known ML model, i.e. Support vector machines (SVMs). The main objective of this paper is to compare the existing ML models with the variants of SVM. Limitations of the existing techniques including the variants of SVM are then drawn. Finally, future directions are presented.

First-principles calculation has been performed to investigate the effect of strain on the magnetic moment of Fe-doped MoTe₂ monolayer. Our results show that the Fe-doped MoTe₂ monolayer is semiconductor with the magnetic moment of 2.037 ${\mu }_{\mathrm{\text{B}}}$. By analyzing the density of states, we find that the magnetic moment is mainly contributed by the Fe atom. When the biaxial strain is applied along the layer, the results show that the magnetic moment is almost unchanged when the compressive strain is under 5% and tensile strain is under 7%. However, as the strain increases, the magnetic moment decreases to almost zero with compressive strain larger than 7%, and the magnetic moment begins to increase with the tensile strain larger than 8%, which indicates the different effects of compressive strain and tensile strain on the magnetism of Fe-doped MoTe₂.

This paper designed a novel three-output reflective packaged grating. The optimized parameters such as the period and depth of the high-efficiency three-output grating with an incident wavelength of 1550 nm can be calculated by rigorous coupled-wave analysis (RCWA). According to the optimized result, the grating can diffract the incident light energy into three orders with an efficiency of nearly 33% under the premise of second Bragg angle incidence and the given duty ratio of 0.5. The diffraction efficiency of the packaged grating is improved compared to the surface-relief three-output grating under second Bragg angle incidence, especially for TE-polarized light.

In this study, we carried out the analysis of the thermal fluctuations on the dynamics of small Josephson junction (JJ). An expression for the fluctuation of Coulomb blockade edge in the case of low and high growing rate of voltage was obtained. It was shown that dynamics of small-sized JJ under thermal fluctuations is determined by the energy ratio-parameter, temperature and growing rate of voltage.

Traffic congestion is now nearly ubiquitous in many urban areas. The improvement of road infrastructure is an effective way to ease traffic congestion, especially the key road links. So, it is a fundamental and important step to identify the key link for improving transportation efficiency. However, most approaches in the current literature use simulated data and need many assumption conditions. The result shows the low comprehensibility and the bad exactitude. This paper provides a new identification method of key links for urban road traffic network (URTN) based on temporal-spatial distribution of traffic congestion. The method involves identifying congestion state, computing time distribution of congestion state and determining key road link. By the cluster analysis of the history field data of URTN, the threshold to determine the traffic congestion of each link can be obtained. Then the time-interval of the traffic congestion can be computed by median filtering. At last, the time-interval coverage is defined and used to determine the target road link whether it is a key road link or not. The method is validated by a real-world case (Beijing road traffic network, BRTN). The result shows the feasibility and accuracy.

In this paper, we have established the new exact solitons solutions of the nonlinear Biswas–Arshed equation which are used to study soliton dynamics in optical fibers, pivotal cloud foundry (PCF) and metamaterials via the prominent approach, known as auxiliary equation method. The obtained solutions disclosed that the suggested method is the essential addition for studying the exact solution of nonlinear Biswas–Arshed equation.

In this paper, based on proposed Riccati mapping technique, we investigated the soliton solutions of fourth-order dispersive nonlinear Schrödinger equation with nonlinearity of dual-power law. The various types of solitons solutions involving some parameters are constructed. These soliton solutions can be useful for understanding the physical nature of the waves spread in the dispersive medium. Furthermore, the Modulation Instability (MI) is discussed by standard linear-stability analysis that shows all achieved results are exact and stable. The movements of some achieved results were presented graphically by giving suitable values to parameters that provide easy understanding to the physical phenomenon of this dynamical model. The obtained results show the simplicity and efficiency of the current used approach.