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The purpose of this paper is performance enhancement of ferrite-assisted synchronous reluctance (FASR) motor using multi-objective differential evolution (MODE) algorithm, considering the significant geometric design parameters.

This work illustrates the optimization of FASR motor using MODE algorithm to enhance the performance of the motor considering barrier angular positions, magnet height, magnet axial length, flux barrier angles of the rotor and air gap length. In the optimization routine to determine the performance parameters, generalized regression neural network-based interpolation is used. The results of MODE are validated with multi-objective particle swarm optimization algorithm and multi-objective genetic algorithm.

The design optimization procedure developed in this work for FASR motor aims at achieving multiple objectives, namely, average torque, torque ripple and efficiency. With multiple objectives, it is essential to give the designer the tradeoff between different objectives so as to arrive at the best design suitable for the application. The results obtained in this work justify the application of the MODE approach for FASR motor to determine the various feasible solutions within the bounds of the design.

Analysis, design and optimization of synchronous reluctance motor has been explored in detail to establish its potential for variable speed applications. In recent years, the focus is toward the electromagnetic design of hybrid configurations such as FASR motor. It is in this preview this work aims to achieve optimal design of FASR motor using multi-objective optimization approach.

The results of this work will supplement and encourage the application of FASR motor as a viable alternate for variable speed drive applications. In addition, the application of MODE to arrive at better design solutions is demonstrated.

The approach presented in this work focuses on obtaining enhanced design of FASR motor considering average torque, torque ripple and efficiency as performance measures. The posteriori analysis of optimization provides an insight into the choice of parameters involved and their effects on the design of FASR motor. The efficacy of the optimization routine is justified in comparison with other multi-objective algorithms.

Industrial drives require appropriate control systems for reliable and efficient performance. With synchronous reluctance machines (SynRMs) slowly replacing the most commonly used induction, switched reluctance and permanent magnet machines, it is essential that the drive and its control be properly selected for enhanced performance. But the major drawback of synchronous reluctance motor is the presence of high torque ripple as its design is characterized by large number of variables. The solutions to reduce torque ripple include design modifications, choice of proper power electronic inverter and PWM strategy. But little has been explored about the power electronic inverters suited for synchronous reluctance motor drive to minimize torque ripple inherently by obtaining a more sinusoidal voltage. The purpose of this paper is to elaborate on the potential multilevel inverter topologies applicable to SynRM drives used in solar pumping applications.

The most significant field-oriented control using maximum torque per ampere algorithm for maximizing the torque production is used for the control of SynRM. Simulation results carried out using Matlab/Simulink are presented to justify the choice of inverter and its control technique for SynRM.

The five-level inverter drive gives lesser core or iron losses in the SynRMin comparison to the three- and two-level inverters due to lower Id current ripple. The five-level inverter reduces the torque ripple of the SynRM significantly in comparison to the three- and two-level inverter fed SynRM drives. The phase disposition-PWM control method used for the inverter shows the least total harmonic distortion (THD) levels in output voltage compared with the other level shifted PWM techniques.

Among the available topologies, a fitting topology is proposed for use for the SynRM drive to have minimal THD, minimal current and torque ripple. Additionally, this paper presents various modulation techniques available for the selected drive system and reports on a suitable technique based on minimal THD of output voltage and hence minimal torque ripple.

Topology optimization (TO) methods have shown their unique advantage in the innovative design of electric machines. However, when introducing the TO method to the rotor design of interior permanent magnet (PM) synchronous machines (IPMSMs), the layout parameters of the magnet cannot be synchronously optimized with the topology of the air barrier; the full design potential, thus, cannot be unlocked. The purpose of this paper is to develop a novel method in which the layout parameters PMs and the topology of air barriers can be optimized simultaneously for aiding the innovative design of IPMSMs.

This paper presents a simultaneous TO and parameter optimization (PO) method that is applicable to the innovative design of IPMSMs. In this method, the mesh deformation technique is introduced to make it possible to make a connection between the TO and PO, and the multimodal optimization problem can thereby be solved more efficiently because good topological features are inherited during iterative optimization.

The numerical results of two case studies show that the proposed method can find better Pareto fronts than the traditional TO method within comparable time-consuming. As the optimal design result, novel rotor structures with better torque profiles and higher reluctance torque are respectively found.

A method that can simultaneously optimize the topology and parameter variables for the design of IPMSMs is proposed. The numerical results show that the proposed method is useful and practical for the conceptual and innovative design of IPMSMs because it can automatically explore optimal rotor structures from the full design space without relying on the experience and knowledge of the engineer.

Internet service providers (ISPs) constitute a highly competitive market, while the unstable market conditions directly affect customer preferences and make ISPs to develop a “mass customization” strategy, individualizing services and approaching every customer in an individual way. However, customization requires an in‐depth analysis of current customer preferences and an evaluation of future behavior. The main objective of the paper is to present a framework for analyzing changes of customer preferences.

The paper presents detailed results of independent customer satisfaction surveys conducted in different time periods in the Greek ISP market. The analyses are based on non‐parametric statistical techniques and the multicriteria satisfaction analysis method, which is a multicriteria preference disaggregation approach.

Results are mainly focused on the evaluation of potential trends of e‐customer preferences. Furthermore, results of a benchmarking analysis are also presented, based on the evolution of satisfaction levels for the quality characteristics of the provided services.

Future research in the context of the presented study may be focused on satisfaction benchmarking analysis, given the rapid changes of the market conditions. An extended satisfaction survey will give the ability to analyze customer preferences in comparison with the main ISP competitors.

The presented study may help organizations in highly competitive markets dominated by rapid technological progresses to track short‐term changes of customer preferences.

The analyses presented are based on the combination of multicriteria analysis and non‐parametric statistics. The main advantage of these methods is that they respect the qualitative (ordinal) form of collected survey data.

The purpose of this paper is to conceptually articulate the differing needs of graduates and graduate employers, which can be competing or complementary in nature. Drawing from theoretical frameworks of career ecosystems and the new psychological contract, a set of propositions are presented using three themes: career management, development of talent and technological change.

A conceptual design offering a conceptual model through adopting the career ecosystem and new psychological contract as a framework.

These propositions offer a new conceptual model, which provides a practical contribution by articulating sustainability of graduates’ careers through employability at the graduate level and competitive advantage at the employer level.

The paper offers important contributions to theory by connecting career management and vocational career literature through acknowledging shared constructs of life-long learning and sustainable employability for graduates. These two streams are often developed in parallel, thus this paper helps to bridge the gaps in respective research agendas. This paper therefore has the originality of helping to advance the fields of career theory and sustainable human resource management.

The purpose of this paper is to propose an improved differential evolution algorithm (DEA) suitable for motor’s model identification.

The mutation operation of the standard DEA is improved, and the adaptive coefficient is designed to adjust the optimization process.

The application of motor model identification shows that the proposed improved DEA is more robust, with higher modeling accuracy and efficiency, and is more suitable for motor identification modeling applications. Compared with the ultrasonic motor model established by using particle swarm algorithm, the model established in this paper has higher precision.

This paper explores an improved DEA suitable for motor identification modeling. The algorithm can not only obtain the optimal solution but also effectively reduce the iterative generations and time required in the process of optimization identification.

Lithium disilicate glass-ceramics (LS2 GC) are widely used as dental prosthetics and dental restorations. Based LS2 GC have hardness and translucency similar to that of natural teeth. This study aims to investigate the tribological features of LS2 GC with crystalline volume fraction of 64% and different crystal sizes from 8 µm to 34 µm for different counterparts.

The tribological behavior was investigated using a pin-on-disc tribometer with alumina and tungsten carbide (WC) spheres, applied load of 5 N and sliding speed of 5 cm/s at normal conditions. The coefficient of friction was measured continuously up to 10,000 sliding cycles. The specific wear rate was calculated from tribological and profile measurements. The wear mechanism was investigated by surface morphology analysis.

The coefficient of friction during running-in varied from 0.8 to 1.0 for the alumina counterpart, because of severe wear. Afterwards, it reduced and reached a stationary regime, characterized by a mild wear regime and the formation of a tribolayer formed by the debris. For the WC counterpart, the coefficient of friction curves increased initially with sliding cycles up to a stationary regime. The samples tested against WC presented the lowest specific wear rate (k), and no variation of wear rate with crystal size was observed. For samples tested against the alumina, crystallization and crystal size increased the wear resistance.

This study evaluated the effect of different counterfaces on the tribological properties of the LS2 GC, an important glass-ceramic base for many dental prosthetics and dental restorations, discussing results in light of the contact mechanics. Different specific wear rates, wear regimes and dependence on the glass-ceramic microstructure were observed depending on the counterpart.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-08-2019-0352/

This study aims to address two research questions. First, do the agricultural extension services have an impact on the potential outcomes considered in the primary studies, and to what extent? Second, how sensitive is the reported impact to the study-specific characteristics in the primary studies?

The paper synthesizes 45 studies that assessed the causal impact of agricultural extension services published in 2004–2021, using meta-regression analysis. It considers three measures of effect sizes – Cohen’s, Hedges and principal correlation coefficient (PCC) – to standardize the reported impact of agricultural extension services in the primary studies.

The empirical results show that, on average, agricultural extension services have statistically significant and positive impacts on the potential outcomes identified in the primary studies. However, the magnitude of the impact is considered medium-sized. Other results show that the effect size estimates of agricultural extension services' impact significantly vary with the data type (cross-sectional data vs. panel data), research design (non-experimental vs. experimental design) and econometric methods employed in the primary studies.

One can argue that the medium-sized impact we estimated indicates evidence of a moderate, weak relationship between agricultural extension services and the potential outcomes considered in the primary studies. This means that agricultural extension services need to be restructured in the current form to stimulate change in the agricultural sector globally. In addition, the sensitivity of effect sizes to study attributes (i.e. data types, research design and econometric methods) shows that researchers and academicians need to pay attention to these attributes to provide more reliable estimates for policy purposes.

This is the first study that attempts to shed light on the overall performance of agricultural extension services using a meta-regression analysis approach.

The purpose of this paper is to present the results of a comprehensive study on the specialisations or career tracks supported by the Information Systems (IS) curriculum in the UK.

The study utilises the recently published IS curriculum guidelines (IS 2010) to develop a method for ranking the career tracks of undergraduate IS courses in the UK.

The research presents a prioritised list of graduate IS careers by taking into account the entire IS course provision in the UK. At the same time, it offers data about the size of the IS curriculum in terms of universities in the UK and the number/type courses they offer.

The study relies on a previously undeveloped method for measuring career specialisations for UK IS graduates. Additional work is needed to validate the results through comparisons with alternative methods of measuring the careers supported by IS degree courses.

By having concrete data about the state of the IS curriculum in relation to its employability opportunities, the IS academy can make more informed decisions about future curriculum development. Further comparative research can be undertaken to support arguments about the relevance of the IS curriculum to industry needs.

There has been no similar UK study on this scale which examines the state of the IS curriculum in relation to the career opportunities it offers. The development of the method for this study also offers insights into the structure and recommendations presented by IS 2010.

This study aims to examine teachers’ efficacy to use iPad for teaching, their perceived impact of 1:1 iPad implementation in the classroom and the role of both variables in predicting teachers’ adoption of the iPad.

This paper opted for multiple linear regression analysis of the data from a total of 91 teachers (44 male and 47 female). All participating teachers are from upper-middle-class private schools who have been using iPad in their classrooms for at least three months. All three variables being studied are measured using instruments developed by the researcher and self-rated by participating teachers: iPad-Teaching Efficacy (iTE), Perceived Impact of iPad in the Classroom (iPI) and iPad Actual Use for Teaching (iAU). All three instruments have good internal reliability and validity, with an alpha coefficient of 0.97, 0.92 and 0.93 respectively.

The paper provides empirical insights about factors contributing to teachers’ technology adoption (specifically iPad) in the classroom. It suggests that teachers’ efficacy significantly predicts their actual use of the iPad for teaching, but teachers’ perceived impact of the implementation does not.

These research findings play an important role in designing a program for technology adoption in schools, especially in Indonesia.