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The paper purposes a novel SFPM machine topology with radial and circumferential permanent magnets (PMs). The paper aims to discuss this issue.

In order to reduce the flux leakage in the stator-outer region and consequently achieve higher magnetic material utilization in switched flux permanent magnet (SFPM) machine, a novel topology with radial and circumferential PMs is proposed. This topology (SFRCPM) has the same structure as conventional SFPM (CSFPM) machine except of the additional set of radially magnetized PMs located around the back iron and surrounded by a laminated ring frame. Using finite element analysis (FEA) the influence of the design parameters on the performance is investigated in order to obtain an effective optimization procedure. Internal and external rotor SFRCPM machines with either NdFeB or ferrite magnets are investigated, optimized and compared with the CSFPM machine having the same size, copper loss and stator/rotor pole combination.

It is concluded that comparing SFRCPM with its CSFPM machine counterpart, internal rotor SFRCPM machine can achieve high PM flux-linkage per magnet volume, however reduced slot area leads to low output torque, whereas external rotor SFRCPM machine can produce higher torque and torque per magnet volume.

This paper proposes a novel SFPM machine topology.

The purpose of this paper is to investigate and compare the influence of end-effect on the torque-speed characteristics of three conventional switched flux permanent magnet (SFPM) machines having different stator/rotor pole combinations, i.e. 12/10, 12/13 and 12/14 as well as three novel topologies with less permanent magnets (PMs), i.e. multi-tooth, E-core and C-core.

SFPM machines combine the advantages of simple and robust rotor and easy management of the temperature due to the location of the PMs and armature windings on the stator. However, due to spoke location of the PMs a large flux leakage in the end region, i.e. end-effect, can be observed which could result in a large reduction in the electromagnetic performance. Therefore, the influence of end-effect on the torque-speed characteristics is investigated. 3D-finite element analyses (FEA) results are compared with their 2D-FEA counterparts in order to account for the end-effect influence.

It has been concluded that due to end flux leakage, lower torque capability in the constant torque region is observed in the six machines. However, improved flux-weakening capability in the conventional machines can be exhibited at high current levels, whereas due to the large inductance lower power capability in the multi-tooth, E-core and C-core machines is obtained.

The influence of temperature rise on the performance is not included.

This paper has analysed the influence of end-effect on the torque-speed characteristics of several SFPM machines.

The purpose of this paper is to comparatively study the conventional, i.e. single magnet, and novel hybrid-magnet switched-flux permanent-magnet (HMSFPM) machines.

The HMSFPM machines utilize two magnet types, i.e. low-cost ferrites and NdFeB. Thus, a set of magnet ratios (?), defined as the quotient of the NdFeB volume to the total PM volume, is introduced. This allows any desired performance and cost trade-off to be designed. Series- and parallel-excited magnet configurations are investigated using 2-dimensional finite element analysis.

The torque of the HMSFPM machines is lower than the NdFeB SFPM machine but the flux-weakening performance is improved for similar machine efficiency. If the machine dimensions are unconstrained, the HMSFPM machines can have the same torque for reduced material costs and a moderate increase in machine dimensions. Ferrite SFPM machines have the lowest cost for the same torque but a significant increase in machine dimensions is required. Finally, the series-excited HMSFPM machine is the preferred over the parallel-excited HMSFPM machine because it has superior demagnetization withstand capability.

Mechanical and winding eddy current losses are not considered in the efficiency map calculations.

The NdFeB SFPM, ferrite SFPM, series-excited HMSFPM, and the parallel-excited HMSFPM machines are compared for their electromagnetic performance, flux-weakening, PM demagnetization, efficiency, and material costs.

This study examines the role of industry competition, market capitalization, and debt levels in the relationship between profitability and firm value (FV). The sample included companies listed on the Indonesia Stock Exchange (IDX) in the manufacturing sector in 2017–2019. This study provides empirical evidence that the high level of industrial competition (IC), low level of market capitalization (market value of equity, MVE), and high levels of debt (debt-to-assets ratio, DAR) weaken the effect of profitability as measured by return on assets (ROA) on FV as measured by Tobin’s Q. Profitability is not even related to FV for firms facing high industry competition. In addition, profitability only has a marginal positive relationship with FV for firms with relatively small market capitalizations. These findings suggest that the relationship between profitability and FV is not monotonous but is influenced by the level of industry competence, market capitalization, and debt.

The purpose of this study is to develop a novel mechanical flux-weakening topology for the switched flux permanent magnet (SFPM) machine to extend the speed range, which will be suitable for the electric vehicles and hybrid electric vehicles.

The 3 dimensional mechanical flux-weakening model with flux adjusters (FAs) in the end-cap is established. Subsequently, the electromagnetic performance is compared between the SFPM machine with FAs in the end-cap and without FAs. The open circuit flux-linkage is calculated by finite element analysis (FEA) to investigate the influence of this mechanical flux-weakening topology together with the d/q-axis inductance. The flux-weakening capability and torque-speed curve is also calculated.

The proposed topology decreases the permanent magnet flux-linkage and increases the d-axis inductance, which improve the flux-weakening capability simultaneously. Subsequently, the speed range and constant power region are much wider than those without FAs. Finally, the prototype is fabricated and the measured result of the open circuit back electromotive force has good agreement with the FEA result.

This paper provides a novel mechanical flux-weakening topology with FAs in the end-cap for the SFPM machine, whose volume is smaller than another mechanical flux-weakening topology with FAs at the stator outside. Thus, higher torque and power density can be obtained compared with the SFPM machine with FAs at the stator outside.

The main purpose of this study was to evaluate students’ perception of blended learning instructional design in a Higher Education Institution (HEI) in the Sultanate of Oman. A course in a bachelor degree was offered using blended learning instructional mode, and students’ feedback was obtained on the impact of blended learning. The study was conducted in Ibra College of Technology, one of the seven colleges under the Ministry of Manpower in the Sultanate of Oman. A course in Business Strategy and HR Management was offered during Summer 2016 using a combination of traditional and online instructional design. A structured questionnaire was administered at the end of the semester to solicit feedback from students. The results of the study highlighted a positive attitude among students towards blended learning courses. The research stressed the requirements for proper infrastructure, training and development initiatives for staff and students, shift to a more focused practical assessment methods to measure the graduate attributes. Student engagement, learner autonomy, connection of learning to real life environments and flexibility all appeared to benefit from the blended learning course.

An appropriate space allocation among different residence types gives higher profitability and liquidity for cash flow management in real estate projects for developers. Thereby, a balance between debt and equity should be kept for capital formation in developers where high level of cost, profit and risk exists. The purpose of this paper is to provide cash flow optimization under debt and equity financing while providing an appropriate space allocation of residence types via synchronous consideration of profitability and liquidity.

A novel optimization methodology that includes project financing, optimization and experimental design modules is proposed. The first module, project financing, considers the flexibility of utilizing one or both of debt financing and equity financing when making capital. The optimization module addresses space allocation among different residence types for a construction while maximizing profitability and liquidity using two mixed-integer linear programming models in a pre-emptive manner. The experimental design module assesses the effects of decisive parameters within the methodology via multivariate analysis of variance (MANOVA).

The proposed methodology is applied to a real-life residential project in Istanbul. The optimization module yielded 42.5% profitability via the first linear programming model and 2.2% trade-off between liquidity and profitability while minimizing the payback period by the second linear programming model. Meanwhile, MANOVA results showed that profit per square meter and sale rate trends are the most prominent factors considering their significant effects on net present value and payback period.

To the best knowledge of the author, related papers focused only on profitability under equity financing. Liquidity (as an objective) and equity financing (as a financing method) have not been handled. Hence, this paper not only performs profitability and liquidity-oriented cash flow optimization under debt and equity financing but also optimizes space allocation of residences for the first time.

This study aims to provide a qualitative framework for satisfactory sustainable education for international accounting students using a meta-synthetic approach.

To determine the components and indicators of satisfactory sustainable education for international accounting students, a meta-synthesis allows for the attainment of the objectives of study. In the first phase of study, international related literature was reviewed (n = 2,176). After several screenings for measuring the quality of the related literature including Critical Appraisals Skills Program (CASP), the total number of selected papers was 48, and 2,128 were excluded.

The present research proposed a comprehensive conceptual model for sustainable education and international accounting students’ satisfaction, with seven components and 63 indicators. To assess the credibility of phases, the indicators were presented to five experts independently. The reliability of the proposed conceptual model was tested using Cohen’s Kappa coefficient and analyzed in SPSS. Kappa’s coefficient showed that the agreement level was high and the reliability was high too.

Sustainable education and student satisfaction are crucial for maintaining a competitive international education market. There are ongoing debates about accounting education, particularly accreditation challenges and the need for clear regulations on academic interaction with practice. Accounting education has also been criticized for being outdated, promoting surface-level learning and neglecting the development of broader skills in university graduates. Therefore, it is important to understand sustainable education for international accounting students. The present study aims to identify the aspects of accounting educational services that international accounting students perceive important for increasing satisfaction. This research provides empirical evidence and suggests potential avenues for future research in other countries.

This study aims to examine whether firms that appear to exhibit high sustainable outputs are more likely to pay higher audit fees than firms without such outputs.

The sustainability outputs are measured using a sustainable product portfolio consisting of four products: clean energy products, eco-design products (EDP), environmental products (EP) and sustainable building projects (SBP). The audit fee variable is measured by the natural logarithm of the total amount of audit fees. The study tests two models of the association between these outputs and audit fees; Model 1 tests this association in the absence of the moderating variable (sustainability committee), and Model 2 tests the association in the presence of the moderating variable.

An analysis of data on 261 European firms from the Refinitiv Eikon database from 2010 to 2019 shows that high sustainability outputs are significantly and positively associated with audit fees. More importantly, this association is moderated by the presence of a board-level sustainability committee, suggesting that this type of committee reflects a factor considered by auditors in their audit risk assessment practices. The findings indicate that in Model 1, one (EP) out of four variables has a significant and positive association with audit fees, while in Model 2 and in the presence of sustainability committee, two variables (EP and EDP) have a significant and negative association with audit fees. However, the robust analysis shows that three variables (EP, EDP and SBP) have significant and negative associations with audit fees.

The study findings have important implications for policymakers, auditors and firms’ managers. For policymakers, the findings provide support for the argument that sustainable attitudes incentivise firms to manage sustainable product profiles more effectively. As such, policymakers should incentivise firms to establish a sustainability committee and regulate its role and responsibilities. Auditors should coordinate with the sustainability committee to facilitate audit efforts and reduce audit fees.

Understanding the relationship between sustainable products and audit fees will allow firms to improve their portfolio of sustainable products. In addition, other social implications of this study relate to improving relationships with society by establishing a sustainability committee that is responsible to communicate with that society.

The results support the argument that firms should manage sustainable product portfolios more effectively. In addition, the results of the study highlight the importance of a new variable as a moderator, the sustainability committee, which has not been examined before.