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Article
Publication date: 4 September 2017

Mohammad Hossain Mohammadi, Tanvir Rahman and David Lowther

This paper aims to propose a numerical methodology to reduce the number of computations required to optimally design the rotors of synchronous reluctance machines (SynRMs…

Abstract

Purpose

This paper aims to propose a numerical methodology to reduce the number of computations required to optimally design the rotors of synchronous reluctance machines (SynRMs) with multiple barriers.

Design/methodology/approach

Two objectives, average torque and torque ripple, have been simulated for thousands of SynRM models using 2D finite element analysis. Different rotor topologies (i.e. number of flux barriers) were statistically analyzed to find their respective design correlation for high average torque solutions. From this information, optimal geometrical constraints were then found to restrict the design space of multiple-barrier rotors.

Findings

Statistical analysis of two considered SynRM case studies demonstrated a design similarity between the different number of flux barriers. Upon setting the optimal geometrical constraints, it was observed that the design space of multiple-barrier rotors reduced by more than 56 per cent for both models.

Originality/value

Using the proposed methodology, optimal geometrical constraints of a multiple-barrier SynRM rotor can be found to restrict its corresponding design space. This approach can handle the curse of dimensionality when the number of geometric parameters increases. Also, it can potentially reduce the number of initial samples required prior to a multi-objective optimization.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 36 no. 5
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 4 September 2017

Min Li, Mohammad Hossain Mohammadi, Tanvir Rahman and David Lowther

Manufacturing processes, such as laminations, may introduce uncertainties in the magnetic properties of materials used in electrical machines. This issue, together with…

Abstract

Purpose

Manufacturing processes, such as laminations, may introduce uncertainties in the magnetic properties of materials used in electrical machines. This issue, together with magnetization errors, can cause serious deterioration in the performance of the machines. Hence, stochastic material models are required for the study of the influences of the material uncertainties. The purpose of this paper is to present a methodology to study the impact of magnetization pattern uncertainties in permanent magnet electric machines.

Design/methodology/approach

The impacts of material uncertainties on the performances of an interior permanent magnet (IPM) machine were analyzed using two different robustness metrics (worst-case analysis and statistical study). In addition, two different robust design formulations were applied to robust multi-objective machine design problems.

Findings

The computational analyses show that material uncertainties may result in deviations of the machine performances and cause nominal solutions to become non-robust.

Originality/value

In this paper, the authors present stochastic models for the quantification of uncertainties in both ferromagnetic and permanent magnet materials. A robust multi-objective evolutionary algorithm is demonstrated and successfully applied to the robust design optimization of an IPM machine considering manufacturing errors and operational condition changes.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 36 no. 5
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 29 March 2022

Issah Ibrahim, Mohammad Hossain Mohammadi, Vahid Ghorbanian and David Lowther

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…

Abstract

Purpose

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.

Design/methodology/approach

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.

Findings

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.

Originality/value

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.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering , vol. 41 no. 3
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 8 August 2019

Vahid Ghorbanian, Mohammad Hossain Mohammadi and David Lowther

This paper aims to propose a data-driven approach to determine the design guidelines for low-frequency electromagnetic devices.

Abstract

Purpose

This paper aims to propose a data-driven approach to determine the design guidelines for low-frequency electromagnetic devices.

Design/methodology/approach

Two different devices, a core-type single-phase transformer and a motor-drive system, are used to show the usefulness and generalizability of the proposed approach. Using a finite element solver, a large database of design possibilities is created by varying design parameters, i.e. the geometrical and control parameters of the systems. Design rules are then extracted by performing a statistical analysis and exploring optimal and sub-optimal designs considering various targets such as efficiency, torque ripple and power factor.

Findings

It is demonstrated that the correlation of the design parameters influences the way the data-driven approach must be made. Also, guidelines for defining new design constraints, which can lead to a more efficient optimization routine, are introduced for both case studies.

Originality/value

Using the proposed approach, new design guidelines, which are generally not obtainable by the classical design methods, are introduced. Also, the proposed approach can potentially deal with different parameter–objective correlations, as well as different number of connected systems. This approach is applicable regardless of the device type.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering , vol. 38 no. 5
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 7 January 2020

David Lowther, Vahid Ghorbanian, Mohammad Hossain Mohammadi and Issah Ibrahim

The design of electromagnetic systems for a variety of applications such as induction heating, electrical machines, actuators and transformers requires the solution of a…

Abstract

Purpose

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.

Design/methodology/approach

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.

Findings

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

Originality/value

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.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering , vol. 39 no. 1
Type: Research Article
ISSN: 0332-1649

Keywords

Open Access
Article
Publication date: 30 August 2019

Md. Alamgir Hossain

The mobile payment system has changed payment patterns and has the potential to improve people’s quality of life and increase the bank’s efficiency. In return, the risks…

6392

Abstract

Purpose

The mobile payment system has changed payment patterns and has the potential to improve people’s quality of life and increase the bank’s efficiency. In return, the risks and trust factors inevitably led to increased challenges and become a major concern in the adoption of mobile payment service. Yet, little is known about how risk and trust factors can affect the adoption of mobile payment. Hence, this paper aims to come into contact to solve these issues in the context.

Design/methodology/approach

A comprehensive research model that reflects the customer satisfaction and loyalty to the adoption of mobile payment services is developed and empirically tested using exploratory and confirmatory factor analysis and structural equation modeling.

Findings

Findings reveal that the perceived risk has a significant negative impact on perceived trust and customer satisfaction. Perceived trust is the most important variable in building customer satisfaction, and customer satisfaction is the reasonable predictor of customer loyalty. In addition, gender differences moderate the adoption of the mobile payment service.

Originality/value

The results of the study hold several implications for scholars in the field of technology adoption on financial transactions and offer valuable managerial insights to design their mobile payment adoption strategies to pursue greater acceptance and diffusion of this new payment system.

Details

PSU Research Review, vol. 3 no. 3
Type: Research Article
ISSN: 2399-1747

Keywords

Article
Publication date: 13 August 2021

Mohammad Kasem Alrousan, Amro Al-Madadha, Mohammad Hamdi Al Khasawneh and Adiy Adel Tweissi

The purpose of this study is to investigate the factors that affect students’ behavioral intentions to use virtual classrooms at Princess Sumaya University for Technology…

Abstract

Purpose

The purpose of this study is to investigate the factors that affect students’ behavioral intentions to use virtual classrooms at Princess Sumaya University for Technology (PSUT) in Jordan.

Design/methodology/approach

A quantitative research approach was adopted, an online survey method was used and the data were collected among students at PSUT in Jordan. A total of 511 responses were usable for analysis. A structural equation modeling partial least squares technique was used to examine the hypothesized model.

Findings

The findings reveal that the proposed factors have direct and indirect relationships with behavioral intentions to use virtual classrooms. They show that students’ satisfaction has a direct influence on behavioral intention, while other variables such as instructor characteristics, virtual classroom quality, perceived self-efficacy, perceived organizational support, perceived ease of use and perceived usefulness have an indirect effect on behavioral intentions to use virtual classrooms.

Research limitations/implications

The study was conducted at PSUT in Jordan, which could limit the generalizability of the findings. Furthermore, the present study measured students’ behavioral intentions to use virtual classrooms and future research should consider the actual use of virtual classrooms.

Practical implications

The findings of this study offer significant and useful information to policymakers, instructors, developers and students regarding the use of virtual classrooms in universities. Based on students’ needs and readiness, the findings identify which factors to consider when developing an e-learning system to enhance learning and teaching performance.

Originality/value

This study extends existing knowledge by developing a conceptual model to identify the key factors of virtual classroom adoption in higher education institutions in Arab countries. This study contributes to the literature in the context of e-learning by validating an extended technology acceptance model from an Arab countries perspective and considering the differences in culture, learning style and physical environment compared to developed countries.

Details

Interactive Technology and Smart Education, vol. 19 no. 2
Type: Research Article
ISSN: 1741-5659

Keywords

Article
Publication date: 29 September 2022

Sze Ling Ng, Sajad Rezaei, Naser Valaei and Mohammad Iranmanesh

The objective of this study is to examine the drivers of retail apps satisfaction and continuance intention. An integrative theoretical framework was developed based on…

Abstract

Purpose

The objective of this study is to examine the drivers of retail apps satisfaction and continuance intention. An integrative theoretical framework was developed based on the IS success model, E-S-QUAL and expectancy and disconfirmation model to explain retail apps users’ satisfaction and continuance intention.

Design/methodology/approach

A total of 359 useable data were collected from the targeted Malaysian respondents who had experience in using retail apps services. Data were analysed using the partial least squares technique.

Findings

The results indicate that system quality and e-service quality positively influence retail apps usage satisfaction and have positive direct and indirect effects through satisfaction on continuance intention. The price level has a negative effect on retail apps usage satisfaction. Even though price level has no direct effect on continuance intention to use retail apps, it has an indirect effect on continuance intention through satisfaction.

Originality/value

Although the success of a marketing channel mainly depends on its continuance usage rather than first-time usage, few studies have paid attention to retail apps services. This study contributes to the advancement of knowledge on retail apps by explaining the roles of system quality, e-service quality and price level on retail apps satisfaction and continuance intention. Interestingly, the findings of multi-group analysis imply that female Gen Y app users are more satisfied than males while such differences do not impact their continuance intention to use the retail apps. The findings also suggested that frequency of using apps has no relevance to retail apps user satisfaction, but highly relevant to their continuance intention to use retail Apps services.

Details

Asia-Pacific Journal of Business Administration, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1757-4323

Keywords

Article
Publication date: 12 July 2021

Hamed Mohammed Hamed Mujahed, Elsadig Musa Ahmed and Siti Aida Samikon

This paper aims to examine the determinant factors that influence the adoption of mobile banking by small and medium enterprises (SMEs) in Palestine. The aim of this paper…

Abstract

Purpose

This paper aims to examine the determinant factors that influence the adoption of mobile banking by small and medium enterprises (SMEs) in Palestine. The aim of this paper has supported with the objectives to identify the role of mobile banking practices in enhancing sustainable growth and development of Palestine SMEs; determining the factors that influencing the SMEs as a service and products providers’ intention to adopt mobile banking and proposing a conceptual model for adoption mobile banking development by SMEs sectors in Palestine

Design/methodology/approach

Hypotheses were developed guided by the technology organisation-environment (TOE) model. The primary data was collected from 408 SMEs in Palestine using questionnaires and 8 interviews.

Findings

The empirical results are based on partial least squares analysis and statistical package for the social sciences. The findings presented in this paper reveal that SMEs factors, enabling environment and business model are the main determinant factors affecting the intention to adopt mobile banking by the SMEs sector in Palestine.

Practical implications

The main contribution of this study is the concise identification of the obstacles and facilitators to SMEs’ mobile banking, especially in developing countries. A suggestion for further study was made. The findings could be useful to policymakers, government institutions and agencies especially in Palestine and other development partners in designing and directing their policy intervention.

Originality/value

This study contributes significantly to the theoretical understanding of mobile banking through the development of a mobile banking framework for the SMEs’ sector in Palestine. A major contribution of this study is to the existing knowledge and literature in mobile banking by developing a TOE framework for providers (supply-side) factors in general and in particular in Palestine to fill the gaps in past studies.

Details

Journal of Science and Technology Policy Management, vol. 13 no. 3
Type: Research Article
ISSN: 2053-4620

Keywords

Article
Publication date: 4 December 2018

Younes Menni, Ahmed Azzi, Ali J. Chamkha and Souad Harmand

The purpose of this paper is to carry out a numerical study on the dynamic and thermal behavior of a fluid with a constant property and flowing turbulently through a…

Abstract

Purpose

The purpose of this paper is to carry out a numerical study on the dynamic and thermal behavior of a fluid with a constant property and flowing turbulently through a two-dimensional horizontal rectangular channel. The upper surface was put in a constant temperature condition, while the lower one was thermally insulated. Two transverse, solid-type obstacles, having different shapes, i.e. flat rectangular and V-shaped, were inserted into the channel and fixed to the top and bottom walls of the channel, in a periodically staggered manner to force vortices to improve the mixing, and consequently the heat transfer. The flat rectangular obstacle was put in the first position and was placed on the hot top wall of the channel. However, the second V-shaped obstacle was placed on the insulated bottom wall, at an attack angle of 45°; its position was varied to find the optimum configuration for optimal heat transfer.

Design/methodology/approach

The fluid is considered Newtonian, incompressible with constant properties. The Reynolds averaged Navier–Stokes equations, along with the standard k-epsilon turbulence model and the energy equation, are used to control the channel flow model. The finite volume method is used to integrate all the equations in two-dimensions; the commercial CFD software FLUENT along with the SIMPLE-algorithm is used for pressure-velocity coupling. Various values of the Reynolds number and obstacle spacing were selected to perform the numerical runs, using air as the working medium.

Findings

The channel containing the flat fin and the 45° V-shaped baffle with a large Reynolds number gave higher heat transfer and friction loss than the one with a smaller Reynolds number. Also, short separation distances between obstacles provided higher values of the ratios Nu/Nu0 and f/f0 and a larger thermal enhancement factor (TEF) than do larger distances.

Originality/value

This is an original work, as it uses a novel method for the improvement of heat transfer in completely new flow geometry.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 29 no. 10
Type: Research Article
ISSN: 0961-5539

Keywords

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