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In semi-analytical modeling of spoke-type permanent-magnet (PM) machines (STPMM), the saturation effect is usually neglected (i.e. iron parts are considered to be infinitely permeable) and the PM magnetization is assumed tangential (i.e. magnetization pattern is considered to be tangential-parallel). This paper aims to present an improved two-dimensional (2D) subdomain technique for STPMM with the PM magnetization orientation in quasi-Cartesian coordinates by using hyperbolic functions considering non-homogeneous Neumann boundary conditions (BCs) in non-periodic regions and by applying the interfaces conditions (ICs) in both directions (i.e. t- and θ edges ICs).

The polar coordinate system is transformed into a quasi-Cartesian coordinate system. The rotor and stator regions are divided into primary subdomains, and a partial differential equation (PDE) is assigned to each subdomain. In the PM region, the magnetization orientation is considered in the equations. By applying BCs, the general solution of the equations is determined, and by applying the ICs, the corresponding coefficients are determined.

Using the proposed coordinate system, the general solution of PDEs and their coefficients can mathematically be simplified. The magnetic field and non-intrinsic unbalanced magnetic forces (UMF) calculations have been performed for three different values of iron core relative permeability (200, 800 and ∞), as well as different magnetization orientation values (135 and 80 degrees). The semi-analytical model based on the subdomain technique is compared with those obtained by the 2D finite-element analysis (FEA). Results disclose that the PM magnetization angle can affect directly the performance characteristics of the STPMM.

A new model for prediction of electromagnetic performances in the STPMM takes into account magnetization direction, and soft magnetic material relative permeability in a pseudo-Cartesian coordinate system by using subdomain technique is presented.

The purpose of this paper is to obtain analytic solutions of the (1+1) and (2+1)‐dimensional dispersive long wave equations by the homotopy analysis and the homotopy Padé methods.

The obtained approximation by using homotopy method contains an auxiliary parameter which is a simple way to control and adjust the convergence region and rate of solution series.

The approximation solutions by [m,m] homotopy Padé technique is often independent of auxiliary parameter ℏ and this technique accelerates the convergence of the related series.

In this paper, analytic solutions of the (1+1) and (2+1)‐dimensional dispersive long wave equations are obtained by the homotopy analysis and the homotopy Padé methods. The obtained approximation by using homotopy method contains an auxiliary parameter which is a simple way to control and adjust the convergence region and rate of solution series. The approximation solutions by [m,m] homotopy Padé technique are often independent of auxiliary parameter ℏ and this technique accelerates the convergence of the related series.

This paper aims to present thermal and mechanical stresses in solid and hollow thick-walled cylinders and spheres made of functionally graded materials (FGMs) under the effect of heat generation.

Constant internal temperature and convective external conditions in hollow bodies along with internal heat generation with a combination of outer convective conditions in solid bodies are investigated individually. The effect of the heat convection coefficient on solid bodies is additionally discussed. The variation of the FGM properties in the radial direction is adapted to the Mori–Tanaka homogenization schemes, which produces irregular and two-point linear boundary value problems that are numerically solved by the pseudospectral Chebyshev method.

It has been shown that the selection of the mixtures of FGMs has to be made correctly to keep the thermal and mechanical loads acting on objects at low levels.

In this study, both solid and hollow functionally graded cylinders and spheres for different boundary conditions that are as their engineering applications are examined with the proposed method. The results have demonstrated that the pseudospectral Chebyshev method has high accuracy, low calculation costs and ease of application and can be easily adapted to such engineering problems.

What is it like being a lecturer or teacher? ¹ The classic image is an old, wise, and powerful stoic with oceans of knowledge: a bit like Yoda in Star Wars or Dumbledore in Harry Potter. With the rise of new technology in general and artificial intelligence (AI) in particular, teachers are no longer the sole source of knowledge. Does this mean that the teacher will soon be replaced by technology? Will AI take over?

This chapter considers the risks and benefits of AI in higher education. It argues that AI will not, should not, and, indeed, cannot replace the teacher, because of what is (for now at least) unique to the teacher: namely, her humanity. The idea is simple: to secure good education into the future, one must take advantage of teachers’ uniquely human expertise. State-of-the-art AI applications cannot be bodily present in the same way as human teachers, nor teach existential reflection, norms and values, or a sense of self, history, and society.

The purpose of this paper is to review research studies on process optimisation and machine development that lead to the enhancement of final products in various aspects of the fused deposition modelling (FDM) process.

An overview of the literature, focussing on process parameters, machine developments and material characterisations. This study investigates recent research studies that studied FDM capabilities in printing a vast range of materials from thermoplastics to metal alloys.

FDM is one of the most common techniques in additive manufacturing (AM) processes. Many parameters in this technology have effects on three-dimensional printed products. Therefore, it is necessary to obtain the optimum elements, for example, build orientation, layer thickness, nozzle diameter, infill pattern and bed temperature. By selecting a proper variable range of parameters, the layers adhere strongly and building end-use products of high quality are achievable. A vast range of materials and their properties from polymers to composite-based polymers are presented. Novel techniques to print metal alloys and composites are examined to increase the productivity of the FDM process. Additionally, defects such as shrinkage and warpage are discussed to eliminate the system’s limitations and improve the quality of final products. Multi-axis and mobile machines brought enhancements throughout the process to eliminate obstacles such as staircase defects in the conventional FDM process. In brief, recent developments were identified and a summary of major improvements was discussed in this study for future research.

This paper is an overview that provides information about research and developments in FDM. This review focusses on process optimisation and obstacles in printing polymers, composites, geopolymers and novel materials. Therefore, machine characteristics were examined to find out the accessibility of printing novel materials for different applications.

This study aims to explore a technique of metal additive manufacturing (MAM) for producing parts in aluminium. The proposed technique mimics the process of metal injection moulding but with the tools meant for fused freeform fabrication machines.

The work focusses on the preparation of novel feedstock by mixing the aluminium powder with binders made from different compositions of high-density polyethylene, paraffin wax, petroleum jelly and stearic acid. Further, a novel experimental setup with a paste extruder was designed to print the test samples. A sintering cycle was developed in-house along with a thermal debinding procedure. An experimental campaign was also carried with the proposed technique to establish a proof-of-concept. Produced samples were tested for part density, hardness, compressive strength and tensile strength.

The results indicate geometrical accuracy was an issue owing to the presence of petroleum jelly in the binder-powder mixture. Therefore, machining as a post-processing operation seems to be unavoidable. The study also elucidates that the printed specimen may require further heat treatment to replace wrought alloys. However, the sintered parts show hardness and compressive strength similar to that of wrought aluminium alloy.

The novelty of the work is to develop the cost effective and scalable powder extrusion-based MAM process for printing the aluminium parts.

In this work, the effect of porosity volume fraction, porosity types, material grading index, variable disk profiles and aspect ratio on disk performance was studied by performing limit elastic speed analysis of functionally graded porous rotating disks (PFGM) under thermo-mechanical loading.

The composition change was varied by employing the power law function. The thermo-mechanical properties of PFGM such as Young's modulus and yield strength were estimated using modified rule of mixture, for density and coefficient of thermal expansion rule of mixture was used. The even and uneven distribution of porosity in a disk was taken as uniform, symmetrical, inner maximum and outer maximum. The problem was then solved with the help of the variational principle and Galerkin's error minimization theory.

The research reveals that the grading parameter, disk geometry and porosity distribution have a significant impact on the limit elastic speed in comparison to the aspect ratio.

The study determines a range of operable speeds for porous and non-porous disk profiles that the industry can utilize to estimate structural performance.

A finite element investigation was conducted to validate the findings of the present study. Limit elastic analysis of porous FG disks under thermo-mechanical loading has not been studied before.

The purpose of this paper is to obtain analytic solutions of telegraph equation by the homotopy Padé method.

The authors used Maple Package to calculate the solutions obtained from the homotopy Padé method.

The obtained approximation by using homotopy method contains an auxiliary parameter which is a simple way to control and adjust the convergence region and rate of solution series. The approximation solutions by [m, m] homotopy Padé technique are often independent of auxiliary parameter h and this technique accelerates the convergence of the related series. Finally, numerical results for some test problems with known solutions are presented and the numerical results are given to show the efficiency of the proposed techniques.

The paper is shown that homotopy Padé technique is a promising tool with accelerated convergence for complicated nonlinear differential equations.

The purpose of this study was to perform thermo-mechanical deformation and stress analysis in a functionally graded (FG) hollow cylinder considering steady-state temperature distribution under the effect of rotation, gravity and constant heat generation.

Navier's equation was used to solve the problem, and the obtained results were validated with benchmarks found to be in excellent agreement. The variation of temperature and other material properties such as Young's modulus, density, thermal expansion coefficient and thermal conductivity varied radially as per power-law variation.

The effect of rotation was found to be vital compared to gravity and heat generation when compared individually and in combination. The results of displacement and stresses were presented for varying grading indices.

FG cylinders have huge industrial applications as it opens the possibility of developing structures with a high strength/weight ratio. The present study will benefit industries in identifying the effective grading index that can be used by industries for fabricating FG structures.

The effect of rotation, body force and heat generation on a cylindrical body has not been studied before. Furthermore, the combined effect of rotation, body force and heat generation has been studied to understand the behaviour of cylinders operating under similar conditions.

This qualitative case study aims to identify and analyse the factors influencing the implementation and effectiveness of electronic health record systems (EHRS) in primary health-care (PHC) facilities in Tanzania. This study aims to explore ways to optimize the use of EHRS for better health-care service delivery.

The study uses a qualitative case study design. Data were collected through interviews and focus groups conducted with health-care workers and information and communication technology officers at the PHC facilities in Tanzania. Purposive sampling and data source triangulation were used to address potential biases and limitations associated with the study’s small sample size.

This study identifies several key findings related to the implementation and effectiveness of EHRS in Tanzanian PHC facilities. The primary obstacles include inadequate technical infrastructure, poor internet connectivity and insufficient financial resources. The study suggests a comprehensive strategy for improving EHRS, emphasizing patient and health-care professional involvement in system design, investments in technical infrastructure and connectivity, data quality and accuracy and ongoing technical support and training.

This research contributes to the existing body of knowledge by offering a nuanced understanding of the Tanzanian health-care context. It emphasizes the need for tailored solutions and strategies specific to the region’s challenges and opportunities. The study’s originality lies in its focus on EHRS in the Tanzanian context, providing valuable insights for future initiatives. A key policy implication underscores the importance of a supportive regulatory framework, dedicated resources and consistent stakeholder communication for successful EHRS implementation.