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The purpose of this paper is to present a novel method to identify demagnetization faults in the magnet of a permanent magnet synchronous machine (PMSM) using some externally measurable parameter.

The machine is modelled by using permeance network theory. The new feature introduced in the permeance network is the subdivision of magnets into segments, modelled as bidirectional elements. These bidirectional elements allow taking into account the effect of one element on the other. To detect the demagnetization faults, a gradient‐based algorithm is also developed. This algorithm uses the permeance network model of the PMSM and measurement data of some parameter to find the distribution of remanent induction in the magnet segments.

The methodology presented is able to detect the demagnetization fault using an external data. The measurement data in this paper is obtained through finite element simulations. The fast and accurate convergence of the algorithm makes the model to find its place in magnet fault diagnosis. Results for different magnet fault types have been presented.

This new approach to detect demagnetization fault can serve as a step towards development of better fault‐detection algorithms and fault‐tolerant control schemes.

The purpose of this paper is to present a new model to study inter‐turn short circuit faults in a permanent magnet synchronous machine.

The machine is modeled by using classical two‐axis theory, and the equations are modified to take into account the stator inter‐turn faults. A state space form of the system is presented for dynamic simulations.

The machine model is global and can work in both normal and fault conditions due to a fictitious resistance in the winding circuit. Various simulation results have been presented indicating the fault instant and its corresponding effect. Validation is carried out by transient time finite element simulations.

The model can serve as a step towards development of fault detection and diagnosis algorithms.

The purpose of this paper is to examine the interaction effects of a transverse magnetic field and slip effects of Casson fluid with suspended nanoparticles over a nonlinear stretching surface. Mathematical modeling for the law of conservation of mass, momentum, heat and concentration of nanoparticles is executed.

Governing nonlinear partial differential equations are reduced into nonlinear ordinary differential equations and then shooting method is employed for its solution. The slope of the linear regression line of the data points is calculated to measure the rate of increase/decrease in the reduced Nusselt number.

The effects of magnetic parameter (0=M=4), Casson parameter (0.1=β<8), nonlinear stretching parameter (0=n=3) and porosity parameter (0=P=6) on axial velocity are shown graphically. Numerical results were compared with another numerical approach and an excellent agreement was observed. This study reveals the fact that the Brownian motion parameter and boundary layer thickness have a direct relationship with temperature. Also, Brownian motion and thermophoresis contribute to an increase in the thermal boundary layer thickness.

Despite the immense significance and repeated employment of non-Newtonian fluids in industry and science, no attempt has been made up till now to inspect the Casson nanofluid flow with a permeable nonlinear stretching surface.

The purpose of this paper is to discuss positive spillovers of this project, especially for Pakistan because the majority of the literature discusses challenges associated with China-Pakistan Economic Corridor (CPEC).

This study reviews the available literature to assess the role of CPEC in the sustainable economic development of Pakistan.

This study indicates that CPEC is an ambitious development project because it needs a larger restructuring of the economy of Pakistan and it will be productive with the successful blend of policy changes and participation of the business community in Pakistan. This project primarily creates a huge amount of foreign direct investment for Pakistan, at the same time, it will also create greater trade opportunities to China by giving access to a new market for its trading goods.

This study established that CPEC will improve the economic growth and trade, enhance regional connectivity, overcome energy crises, develop infrastructure and establish people-to-people contacts in both the countries, which will further help to improve the tourism sector.

This study investigates the link between servant leadership and project management effectiveness in developmental projects in non-governmental organisations (NGOs). Further, this study examined the mediating role of conflict resolution and moderating role of organisational culture.

A three-wave survey of 288 non-governmental organisation (NGO) employees was used to evaluate the hypotheses. Hierarchical regression analysis and Hayes' PROCESS macro technique were used for data analysis.

In this study, servant leadership positively affects employee project management effectiveness in developmental projects in NGOs, and conflict resolution mediates the relationship. Furthermore, the results show that organisational culture moderates the positive relationship between servant leadership and employee project management effectiveness. Moreover, the authors investigated the hypotheses via a moderation mediation model. The strength of the mediated link between servant leadership and project management effectiveness (via conflict resolution) depends on organisational culture strength.

Leaders that practice servant leadership care for their employees genuinely and serve them by allowing them to make their own decisions. Every organisation may benefit from this leadership style since it encourages project effectiveness

New empirical data from this study suggests that servant leadership positively and substantially affects employee project management effectiveness in developmental projects in NGOs.

This paper aims to fill a gap in the literature of marketing communication by exploring the role of different nudges implemented through advertising and personal selling in enhancing purchase intention and sales of mutual funds in Pakistan.

Data collected by 20 semi-structured individual qualitative interviews in Pakistan were subjected to thematic analysis.

This study reveals the way managers apply different nudges in the form of Islamic beliefs and values in advertising and personal selling to enhance purchase intention and sales of mutual fund products among Muslim customers. Nudges that can be used in marketing communication may include religious cues, religious beliefs, religious values, spiritual elements, halal aspects of investment plans, religious icons and symbols, cultural music and images, appropriateness and correctness of sales messages and communicating halal aspects of mutual funds.

The conclusions are based on findings from a relatively small number of respondents from one investment firm, but they offer an empirical basis for future research on the effect of advertising and personal selling on the sales and purchase intention of mutual fund products in an Islamic society.

This study offers practitioners a better understanding of the marketing communication tools likely to influence consumers’ purchase intention of mutual fund products, with positive implications in creating advertising and sales management in Pakistan.

Despite the prevalence of promoting mutual fund products, little research-based analysis has been available to academics or practitioners.

The purpose of this paper is to study the thermal behavior of radial porous fin surrounded by water-base copper nanoparticles under the influence of radiation.

In order to optimize the response variable, the authors perform sensitivity analysis with the aid of response surface methodology (RSM). Moreover, this study enlightens the applications of artificial neural networks (ANN) for predicting the temperature gradient. The governing modeled equations are firstly non-dimensionalized and then solved with the aid of Runge–Kutta fourth order together with the shooting method in order to guess the initial conditions.

Numerical results are analyzed and presented in the form of tables and graphs. This study reveals that the temperature of the fin is decreasing as the wet porous parameter increases (m₂) and the temperature for 10% concentration of nanoparticles are higher than 5 and 1%. Physical parameters involved in the study are analyzed and processed through RSM. It is come to know that sensitivity of temperature gradient to radiative parameter (Nr) and convective parameter (Nc) is positive and negative to dimensionless ambient temperature (θ_a). Furthermore, after ANN training it can be argued that the established model can efficiently be used to predict the temperature gradient over a radial porous fin for the copper-water nanofluid flow.

To the best of our knowledge, only a few attempts have been made to analyze the thermal behavior of radial porous fin surrounded by copper-based nanofluid under the influence of radiation and convection.

This study comprehensively aims to review the key influential and intellectual aspects of spillovers between Islamic and conventional financial markets.

The study uses the bibliometric and content analysis methods using the VOSviewer software to analyse 52 academic documents derived from the Web of Sciences (WoS) between 2015 and June 2022.

The results demonstrate the influential aspects of spillovers between Islamic and conventional financial markets, including the leading authors, journals, countries and institutions and the intellectual aspects of literature. These aspects are synthesised into four main streams: research between stock indexes; studies between stock indexes, oil and precious metal; works between Sukuk, bond and indexes; and empirical studies review. The authors also propose future research directions in spillovers between Islamic and conventional financial markets.

Our study is subject to several limitations. Firstly, the authors only used the WoS database. Secondly, the study only includes papers and reviews written in English from the WoS. This study assists academic scholars, practitioners and regulatory bodies in further exploring the suggested issues in future studies and improving and predicting economic and financial stability.

To the best of the authors’ knowledge, no extant empirical studies have been conducted in this area of research interest.

The purpose of this study is to examine the flow and heat transfer performance of titanium oxide/water and copper/water nanofluids with varying nanoparticle morphologies by considering magnetic, Joule heating and viscous dissipation effects. Furthermore, it studies the irreversibility caused by the flow of a hydromagnetic nanofluid past a radiated stretching sheet by considering different shapes of TiO₂ and Cu nanoparticles with water as the base fluid.

In this study, the authors investigated entropy production in an unsteady two-dimensional magneto-hydrodynamic nanofluid regime using water as the base fluid and five unique TiO₂ and Cu nanoparticle morphologies. Using appropriate similarity transformations, the controlling nonlinear system of partial differential equations is transformed into a system of ordinary differential equations. The shooting technique with Runge–Kutta method was then used to solve these equations quantitatively. The findings of this study are depicted graphically, and the skin friction corresponding to various nanoparticle geometries and physical parameter variations is tabulated.

To assess the reliability of the current findings, a tabular representation of the data was compared to that of previously published studies. It is noted that a reduction in thermal energy was detected as a result of the higher levels of Prandtl number (Pr). It is further analysed that the highest heat energy generation of TiO₂ nanoparticles was larger than that of Cu nanoparticles. The most important finding was that the sphere-shaped Cu/H₂O nanofluid had the lowest velocity and greatest temperature. Also, Cu nanoparticles in the shape of platelets generate the most entropy, while TiO₂ nanoparticles in the shape of spheres generate the least.

To the best of the knowledge of the authors, the attempt to investigate the previously unexplored shape effects of TiO₂ and Cu nanoparticles on the heat transfer enhancement and inherent irreversibility caused by hydromagnetic nanofluid flow past a radiated stretching sheet with magnetic, Joule heating and viscous dissipation effects. This study fills this gap in the existing literature and encourages scientists, engineers and businesses to do more research in this area. This model can be used to improve heat transfer in systems that use renewable energy, thermal management in industry and the processing of materials.

The purpose of this paper was to study laminar fluid flow and convective heat transfer in a conical gap at small conicity angles up to 4° for the case of disk rotation with a fixed cone.

In this paper, the improved asymptotic expansion method developed by the author was applied to the self-similar Navier–Stokes equations. The characteristic Reynolds number ranged from 0.001 to 2.0, and the Prandtl numbers ranged from 0.71 to 10.

Compared to previous approaches, the improved asymptotic expansion method has an accuracy like the self-similar solution in a significantly wider range of Reynolds and Prandtl numbers. Including radial thermal conductivity in the energy equation at small conicity angle leads to insignificant deviations of the Nusselt number (maximum 1.23%).

This problem has applications in rheometry to experimentally determine viscosity of liquids, as well as in bioengineering and medicine, where cone-and-disk devices serve as an incubator for nurturing endothelial cells.

The study can help design more effective devices to nurture endothelial cells, which regulate exchanges between the bloodstream and the surrounding tissues.

To the best of the authors’ knowledge, for the first time, novel approximate analytical solutions were obtained for the radial, tangential and axial velocity components, flow swirl angle on the disk, tangential stresses on both surfaces, as well as static pressure, which varies not only with the Reynolds number but also across the gap. These solutions are in excellent agreement with the self-similar solution.