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Acoustic noise is a crucial performance index in the design of electrical machines. Due to the challenges associated with modelling a complete motor, the stator is often used to estimate the sound power in the prototyping stage. While this approach greatly reduces lengthy simulations, the actual sound power of the motor may not be known. But, from the acoustic noise standpoint, not much is known about the correlation between the stator and complete motor. This paper, therefore, aims to use the sound pressure levels of the stator and the full motor to investigate the existence of correlations in the interior permanent magnet synchronous motor.

A multiphysics simulation framework is proposed to evaluate the sound pressure levels of multiple motor geometries in a given design space. Then, a statistical analysis is performed on the calculated sound pressure levels of each geometry over a selected speed range to compare the correlation strength between the stator and the full model.

It was established that the stator and the complete motor model are moderately correlated. As such, a reliance on the stator sound power for design and optimization routines could yield inaccurate results.

The main contribution involves the use of statistical tools to study the relationship between sound pressure levels associated with the stator geometry and the complete electric motor by increasing the motor sample size to capture subtle acoustic correlation trends in the design space of the interior permanent magnet synchronous motor.

Evaluating the multiphysics performance of an electric motor can be a computationally intensive process, especially where several complex subsystems of the motor are coupled together. For example, evaluating acoustic noise requires the coupling of the electromagnetic, structural and acoustic models of the electric motor. Where skewed poles are considered in the design, the problem becomes a purely three-dimensional (3D) multiphysics problem, which could increase the computational burden astronomically. This study, therefore, aims to introduce surrogate models in the design process to reduce the computational cost associated with solving such 3D-coupled multiphysics problems.

The procedure involves using the finite element (FE) method to generate a database of several skewed rotor pole surface-mounted permanent magnet synchronous motors and their corresponding electromagnetic, structural and acoustic performances. Then, a surrogate model is fitted to the data to generate mapping functions that could be used in place of the time-consuming FE simulations.

It was established that the surrogate models showed promising results in predicting the multiphysics performance of skewed pole surface-mounted permanent magnet motors. As such, such models could be used to handle the skewing aspects, which has always been a major design challenge due to the scarcity of simulation tools with stepwise skewing capability.

The main contribution involves the use of surrogate models to replace FE simulations during the design cycle of skewed pole surface-mounted permanent magnet motors without compromising the integrity of the electromagnetic, structural, and acoustic results of the motor.

The design of electromagnetic systems for a variety of applications such as induction heating, electrical machines, actuators and transformers requires the solution of a multi-physics problem often involving thermal, structural and mechanical coupling to the electromagnetic system. This results in a complex analysis system embedded within an optimization process. The appearance of high-performance computing systems over the past few years has made coupled simulations feasible for the design engineer. When coupled with surrogate modelling techniques, it is possible to significantly reduce the wall clock time for generating a complete design while including the impact of the multi-physics performance on the device.

An architecture is proposed for linking multiple singe physics analysis tools through the material models and a controller which schedules the execution of the various software tools. The combination of tools is implemented on a series of computational nodes operating in parallel and creating a “super node” cluster within a collection of interconnected processors.

The proposed architecture and job scheduling system can allow a parallel exploration of the design space for a device.

The originality of the work derives from the organization of the parallel computing system into a series of “super nodes” and the creation of a materials database suitable for multi-physics interactions.

Globally, information and communication technology (ICT) is regarded as a reliable tool that facilitates economic development and propels sustainable development. However, little empirical work exists on the specific effects of ICT access and usage on economic and sustainable development. This paper aims to investigate the nexus between ICTs, economic and sustainable development at the global level.

This paper presents ICT for Development (ICT4D) value chain empirical evidence on the linkages between ICTs, economic development and sustainable development goals (SDGs). The research model based on the capability approach is validated by using archival data from 130 global countries and partial least squares–structural equation modelling.

The findings reveal that ICT access and usage significantly influence a country’s attainment of the SDGs. Whilst ICT access plays a crucial role in promoting economic development, ICT usage does not. Also, findings show that economic development significantly mediated the nexus between ICT access and SDGs but not between ICT usage and SDGs. This calls for countries to ensure that access to ICTs is accompanied by a low cost of usage to achieve the full benefits of economic and sustainable development.

Using the ICT4D value chain, this paper empirically shows how ICT readiness and availability in the form of ICT access and ICT uptake (individual ICT use) promote economic development and SDGs (impact). Furthermore, with many studies conducted on SDGs at the country level, this study provides a broader understanding of the roles of ICT access and use on SDGs at the global level. This allows for easy generalisability and reproducibility of results.

This study aims to explore the impact of environmental sustainability on government health expenditure in Africa for the period 2000–2021.

The study employs the generalized method of moments (GMM) technique and utilizes a sample of 43 African countries.

The study reveals that carbon dioxide (CO2) emissions and renewable energy consumption have a positive relationship with health expenditure. For the control factors, we demonstrate that economic growth, urbanization and industrialization have a significant negative influence on health expenditure, while the impact of education on health expenditure is positive.

The study proposes several policy recommendations, including prioritizing investment in renewable energy sources and promoting the use of cleaner energy sources such as wind, solar and hydroelectric power. These measures would help improve environmental quality and reduce government health expenditure.

The study contributes to the limited research on the relationship between environmental quality and health expenditure in Africa. Moreover, it goes beyond previous studies that only considered CO2 emissions and explores the impact of adopting cleaner energy sources on health expenditure.

The purpose of this paper is to explore the interrelationship between macroeconomic factors, firm characteristics and financial performance of quoted manufacturing firms in Nigeria. Specifically, the study investigates the effect of interest rate, inflation rate, exchange rate and the gross domestic product (GDP) growth rate, while the firm characteristics were size, leverage and liquidity. The dependent variable financial performance is measured as return on assets (ROA).

The study used the ex post facto research design. The population comprised all quoted manufacturing firms on the Nigerian Stock Exchange. The sample was restricted to companies in the consumer goods sector, selected using non-probability sampling method. The study used multiple linear regression as the method of validating the hypotheses.

The study finds no significant effect for interest rate and exchange rate, but a significant effect for inflation rate and GDP growth rate on ROA. Second, the firm characteristics showed that firm size, leverage and liquidity were significant.

The study has implications for regulators and policy makers in formulating policy decisions. In addition, managers may better understand the interplay between macroeconomic factors, firm characteristics and profitability of firms.

Few studies have addressed the interplay of macroeconomic factors and firm characteristics in determining the profitability of manufacturing firms in the country and developing countries in general.

This study explores the socioeconomic benefits and challenges of smock dealership in Tamale. Despite the relevance of the African traditional garment sector in the socio-cultural and economic development of local and national economies, the industry is bedeviled with a plethora of challenges. Empirical evidence also confirms that African management practices have been largely dependent on western ideologies without taking cognisance of the unique features of indigenous practices. This case study provides an account of successful indigenous business practices among smock dealers in the Tamale Metropolis of Ghana, employing mainly qualitative descriptive research methods. Manual thematic analysis was utilised on the qualitative data. Findings showed that smock businesses offer economic/financial benefits such as income generation, family up-keep, trade, serves as wedding attires, social networks, projects northern cultures, sources of income and livelihood. We also found various advantages of deploying technology in smock business and these include efficiency, productivity, fraud prevention, financial benefits to the producers, competitiveness and globalisation via social media, and customer relationship building. It is recommended that the government make wearing made-in-Ghana clothing a policy and enforce its use. Also, the Ghanaian government and NGOs should make industrial sewing machines available to encourage the business, thereby increasing smock production.

The purpose of this paper is to analyze the influence of job satisfaction on hostage employee loyalty in Isfahan Province Gas Company (IPGC).

The statistical population of this study included the formal recruited employees of IPGC out of which, 212 employees have been selected using a stratified random sampling method. A questionnaire has been developed and used for data collection regarding job satisfaction and employee loyalty. In this study along with the other studies of the authors, employees of IPGC were classified into four different categories on the basis of loyalty matrix, and the majority (78 percent) of them were located in the hostage category. Structural equation modeling has been used for data analysis.

The findings imply that job satisfaction does not have a significant influence on the loyalty of hostage employees.

Organizations are encouraged to identify the individual and organizational factors and obstacles, take necessary measures to increase job satisfaction and maintain the level of employee loyalty and gradually shift them from the hostage category to the apostle category, which results in an increased number of loyal and satisfied employees.

This study indicates how the application of the concepts of loyalty matrix, particularly its hostage category, can be expanded in the field of organizational behavior management.

The purpose of this study is to investigate a framework for knowledge retention to support business continuity in cross-border mergers of the telecommunications industry in Lesotho.

This study applied a qualitative case study, with data collected through interviews from a purposively selected sample of staff members who held managerial positions. Information in this study was partially extracted from the PhD thesis of Dr Tseole ET supervised by Prof Ngulube P at the University of South Africa completed in 2021.

The study discovered that a considerable amount of knowledge may have been lost because employees who either left the organisation or those who were apparently forced to resign during the process had left without any proper knowledge retention arrangements.

The framework proposed in this study may be used in framing future studies as a theoretical framework. The study also provides new literature for review and discussion of background in future related studies.

The framework provided in the study may be used as a benchmark in the knowledge management industry and/or organisations for policy development or improvements and implementation of knowledge retention strategies.

Through recommendations and framework provided by this study, organisations will be able to improve their services to their sphere of influence in the surrounding communities. So, community will be receiving an improved and good service at all the times.

A framework for facilitating knowledge retention in the cross-border mergers of the telecommunications industry is therefore proposed and the researchers believe it will be helpful to the organisation for improving knowledge retention going forward, particularly in the merger process.

This study aims to examine the role of returning Somali diaspora entrepreneurs on firm performance and their perceived environmental obstacles.

The paper draws on a broad literature review and covers a theoretical background to develop a research framework. It presents several propositions to be empirically tested to determine the influence of returnee entrepreneurs’ success and the challenges they face in the process.

The paper offers an overview of how Somali diaspora returnee entrepreneurs can use their resources to succeed in their business and the possible environmental uncertainties that could hinder them. The study highlights some under-researched areas and provides future research directions.

A research investigation is needed to test the proposed conceptual framework empirically. Further research is also recommended to use other predictors when investigating the perceived environmental uncertainty faced by returnee entrepreneurs.

In the diaspora entrepreneurship literature, returnee entrepreneurs in post-conflict African countries did not get enough attention. Hence, the study will contribute theoretically to the literature.

The paper provides a conceptual framework that will help understand returnee entrepreneurs in post-conflict states in Africa, paving the way for empirical studies on the topic.