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This paper aims to establish the mathematical model and solve the complex calculation multi-field coupling problem for an electromagnetic overhead transmission line galloping excitation test system.

An electromagnetic excitation test system is introduced. To calculate the vibration response of the transmission line, a transient coupled finite element model containing electromagnetic repulsive mechanism and transmission line system was established. Considering the advantages of Newmark-ß algorithm and fourth-order Runge–Kutta algorithm, the two algorithms are combined to solve the model. Compared with the simulation results of existing commercial finite element software, the accuracy of the calculation model of electromagnetic force and wire vibration response are verified.

Comparison results show that the proposed calculation model can accurately obtain the force of electromagnetic mechanism and the vibration response of the overhead power lines, and improve the calculation efficiency. The calculation results show that vibration under electromagnetic excitation presents a double half-wave mode, and the galloping amplitude varies according to the charging voltage.

This paper built the transient simulation model for a galloping test system. The Newmark-ß algorithm and the fourth-order Runge–Kutta algorithm are used to solve the model. The research results are of great significance for the actual galloping test system design.

This paper aims to propose an electromagnetic prismatic joint with variable stiffness. The joint can absorb the sudden shocks and improve the natural dynamics of robotics. The ability of regulating the output stiffness can also be used for force control in industrial applications.

Unlike some existing designs of variable stiffness joints (VSJs) in which the stiffness regulation is implemented using the stiffness adjustment motor and mechanisms, the main structure of the electromagnetic VSJ is a permanent magnet (PM) arranged inside coaxial cylinder coils. The adjustment of input current can cause the change of magnetic force between the PM and the cylinder coils, and thus leads to the variation of output stiffness.

According to the theoretical model, the output stiffness of the electromagnetic VSJ is linearly proportional to the input current. The experiments further indicate that the current-controlled stiffness can make the stiffness variation response of this VSJ more rapid for practical applications. Due to the large damping introduced by the copper-based self-lubrication bearings, the VSJ shows good properties in motion positioning and trajectory tracking.

In summary, the electromagnetic VSJ is compact in size and light in weight. It is possible to realize the online adaptability to work conditions with dynamic load by using this VSJ.

This paper seeks to present a novel perspective on the interplay of forces that govern the dynamics of the massively complex multi‐body system that is our physical universe. It offers a consistent, coherent and complete rationale for the phenomenon referred to as “gravitation”. This includes notably, for the first time, an explanation for the mechanism by which “matter tells space how to curve and curved space tells matter how to move”, and also possible causal explanations for the various outcomes of Einstein's equivalence principle.

Starting from the well‐supported premise that elementary particles are formed from closed‐loop electromagnetic energy flows, the likely impact of such constructs on the behaviour of large‐scale dynamic systems is analysed from first principles.

Gravitation is shown to be a natural consequence of such a construct. The warping of space in the presence of gravitating mass, consistent with the view presented by general relativity, is shown to relate to a clearly comprehensible physical structure with a well‐defined causation. Possible explanations are offered for: gravitational time dilation; gravitational red shift; gravitational potential energy; and slowing and bending of light in a gravitational field.

This novel perspective opens a wide range of potential avenues of innovative research, both pure and applied.

A variety of new technologies may prove to be open to development, notably in the aerospace field. Antigravity technologies, whilst amenable to investigation and possible development, may prove highly energy‐intensive.

This paper is totally original and of very significant potential value in various respects.

The purpose objective of this study is to identify the friction coefficient and friction effect in electromagnetic upsetting (EMU) high-speed forming process.

Based on numerical simulation and upsetting experiment of 2A10 aluminum alloy bar, the friction coefficient between contact surfaces is obtained by combining the fitting displacement distribution function and the electromagnetic-mechanical coupling numerical model, and the influence of friction effect is analyzed.

The maximum impact velocity and acceleration during EMU are 13.9 m/s and −3.3 × 106 m/s², respectively, and the maximum strain rate is 7700 s⁻¹. The functional distribution relationship between friction coefficient combination (FS, FD) and characteristic parameters [upper diameter (D1) and middle diameter (D2)] is established. The values of FS and FD are 0.1402 and 0.0931, respectively, and the maximum relative error is 2.39%. By analyzing the distribution of equivalent stress and strain, it is found that plastic deformation has obvious zoning characteristics and there is serious failure concentration in the strong shear zone.

Friction coefficient significantly affects stress or strain distributions in material forming process, but it is difficult to obtain friction coefficients through experimental tests in the high-speed forming process. In this paper, a multi-field coupling numerical model is proposed to determine friction coefficients and applied to the electromagnetic impact loading process (a high-speed forming process).

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-05-2024-0154/

The purpose of this study is the development of the theoretical fundament of zero-point energy conversion, together with a description of its experimental verification.

The theoretical approach is based on quantum theory, its experimental verification uses a design within electrodynamics.

The new finding is a value for the energy density of the electromagnetic zero-point waves of the quantum vacuum, as far as they can be utilised to operate an energy converter.

The energy density of the zero-point waves defines a principle limitation to the output power of zero-point engines.

The paper demonstrates the fundamental basis for zero-point energy motors at all. Furthermore, it shows how to convert this type of energy into electrical or mechanical energy for practical utilisation in aerospace applications and in many other applications.

The zero-point energy of the quantum vacuum is a new source of energy, which is an important contribution to solve the energy problem. It gives clean energy, inexhaustible, available everywhere at a low price.

The calculation of the energy density of the electromagnetic zero-point waves is new.

While working with clients in the last years of his life, Gordon Pask produced an axiomatic scheme for his Interactions of Actors Theory which is a development of his well known Conversation Theory. These axioms are interpretable as a general theory of self‐organisation and are discussed as characteristic of field concurrence and as part of the second‐order cybernetics canon. An application to population density is reported supported by both kinematic and kinetic simulation. Implications for cardiovascular anti‐coagulation therapy and planetary evolution are discussed.

Helical coil electromagnetic launchers (HEMLs) using motion-induced commutation strategy solve the problem of synchronization control perfectly. HEMLs can meet the requirements of multiple applications such as the electromagnetic catapult, electromagnetic mortar and high-velocity coilgun. The trade-off between the velocity and efficiency is an important basis for these different applications. To optimize such objectives before actual design, the purpose of this paper is to focus on the efficient and flexible calculation model and algorithm. A novel structure of HEML is proposed after the transient simulation by this algorithm, which can improve the energy conversion efficiency and suppress the muzzle arc without affecting the velocity too much.

The equivalent circuit model of the launcher is established and the governing equations are derived. A combination of the four-stage Runge–Kutta method and the trapezoidal quadrature formula are used to solve the governing equations.

With smaller number of turns in the coils of HEML, the velocity is larger and the efficiency is lower. The non-uniform HEML is an effective option to improve the energy conversion efficiency and to suppress the muzzle arc with almost the same muzzle velocity as the conventional HEML.

The paper presents a common model and a flexible fast numerical method which can be used in multi-objective optimization of HEMLs such as the genetic algorithm. A new structure of the non-uniform HEML is proposed to improve the energy conversion efficiency and to suppress the muzzle arc of the launcher.

The paper aims at optimizing magnetic thrusts in the framework of the design of high‐dynamics linear actuators. The goal is to find the optimal topology of the permanent magnets in order to maximize the velocity of the actuator.

The optimization is performed by a topology optimization method. The design space is divided in cells in which the method have to distribute permanent magnets and determine their magnetization directions.

Several aspects of the optimization are discussed in the paper, such as the effect of the introduction of a weight constraint on the thrust. Some issues are highlighted regarding the length of design space for the moving part and the presence of local minimizers in the optimization problem.

Having different magnetization directions in each cell makes the manufacturing harder. The results could thus be completed either by the design of a system able to create such permanent magnets or by the introduction of a constraint limiting the number of magnetization directions.

Finding the optimal topology of magnetic thrusts is motivated by the interest in avoiding the shocks related to mechanical thrusts.

This paper applies the topology optimization approach for the design of magnetic thrusts in order to increase the performances of high‐dynamics linear actuators.

This study aims to explore the synthesis, characteristics and utilization of polymer composites integrated with cutting-edge pigments.

The incorporation of advanced pigments introduces functionalities such as enhanced mechanical strength, thermal stability, ultraviolet resistance and color stability, thus extending the range of applications in diverse fields including automotive, aerospace, electronics and construction.

This review discusses the mechanisms underlying the property enhancements achieved through the incorporation of advanced pigments and highlights recent developments in the field.

Polymer composites incorporating advanced pigments have garnered significant attention in recent years because of their potential to enhance various material properties and broaden their applications. This paper explores the fabrication methods of polymer composites reinforced with organic/inorganic advanced pigments in brief along with their characteristics and applications.

This paper aims to report a case study regarding the combined use of several non‐destructive techniques (NDTs) as a tool in the management of diagnosis and refurbishment of a damaged reinforced concrete building.

Four types of NDTs have been selected and carried out on the pillars of the building: visual inspection, electromagnetic rebar location, sonic test and rebound hammer test. The campaign has been planned and run in order to get the highest amount of reliable data about materials degradation and structural safety with limited costs and limited interference with the functionality of the building.

The diagnostic campaign highlighted the usefulness of the selected techniques in the diagnosis of the type and the amount of degradation, thus permitting a plan of refurbishments to be defined, and to get a realistic estimation of restoration costs.

NDTs' ability to specifically identify a type of damage may be viewed as a reliable tool in assessing and managing the structural life‐cycle cost.

The presented case study highlighted that NDTs are very likely to locate and quantify the damage of materials and buildings, so that they can be considered as one of the most important parts of health monitoring of civil structures and infrastructures.