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This paper explores employee experiences of induction in the Big Four accountancy firms to understand how induction influences new recruits' career aspirations.

Using Bourdieusian sociology, this article adopts an interpretivist multi-method approach through focus groups and semi-structured interviews with 28 newly appointed accounting professionals. The study defines newly appointed as those who have experienced induction within the last two years of their employment.

The study's findings challenge the authenticity of induction from a shared employee consensus. It cites contagious spin, regarding career progression opportunities espoused during induction, at odds with the reality of work, ultimately contributing towards unfulfilled employee aspiration. As current strategies suggest that the intersection between employee aspiration and employer provision in the accountancy profession, is too broad, this study argues for more collaborative inductions. In addition, it proposes that accountancy firms should re-evaluate their current strategies and co-construct more authentic inductions that benefit all stakeholders to develop a stronger psychological contract that positively influences employee aspiration.

The paper posits action-learning as a solution to address employee aspiration in induction campaigns in the accountancy profession.

As aspiration is the genesis of motivation and engagement, this study’s findings suggest that the use of an action-learning ethos in induction activities may provide an opportunity to explore the complexities of employee socialisation and provide a voice to new recruits attempting to influence any tensions or disappointment that may arise, as unmet career aspirations emerge.

The paper posits action learning as a solution to address employee aspiration in induction campaigns in the accountancy profession.

Induction heating processes need to adapt to complex geometries or variable processes that require a high degree of flexibility in the induction heating setup. This is usually done using complex inductors or adaptable resonant tanks, which leads to costly and constrained implementations. This paper aims to propose a multi-level, versatile power supply able to adapt the output to the required induction heating process.

This paper proposes a versatile multilevel topology able to generate versatile output waveforms. The methodology followed includes simulation of the proposed architecture, design of the power electronics, control and magnetic elements and laboratory tests after building a 10-level prototype.

The proposed converter has been designed and tested using an experimental prototype. The designed generator is able to operate at 1 kVpp and 100 A at 250 kHz, proving the feasibility of the proposed approach.

The proposed converter enables versatile waveform generation, enabling advanced tests and processes on induction heating system. The proposed system allows for multifrequency generation using a single inductor and converter, or advanced tests for inductive and capacitive components used on induction heating systems. Unlike previous multifrequency proposals, the proposed generator enables a significantly improved versatility in terms of operational frequency and amplitude in a single converter.

This paper aims to investigate the efficacy of teeth flux sensors in detecting, locating and assessing the severity of short-circuit faults in the stator windings of induction machines.

The experimental study involves inducing short-circuit winding turn variations on the induction machine’s stator and continuously measuring the RMS values across teeth flux sensors. Two crucial steps are taken for machine diagnosis: measurements under load operating conditions for fault detection and measurements under no-load conditions to determine fault location and severity.

The experimental results demonstrate that the proposed approach using teeth flux sensors is reliable and effective in detecting, locating and evaluating the severity of stator winding faults.

While this study focuses on short-circuit faults, future research could explore other fault types and alternative sensor configurations to enhance the comprehensiveness of fault diagnosis.

The methodology outlined in this paper holds the potential to significantly reduce maintenance time and costs for induction machines, leading to substantial savings for companies.

This research contributes to the field by presenting an innovative approach that uses teeth flux sensors for a comprehensive fault diagnosis in induction machines. The originality lies in the effectiveness of this approach in providing reliable fault detection, location and severity evaluation.

This paper aims to propose a novel simple and efficient structure for line-start axial-flux permanent magnet (LSAFPM) synchronous motor, especially regarding the permanent magnets (PMs) demagnetization reduction.

At first, a primitive raw scheme of the new structure for the LSAFPM motor is introduced. Considering this raw scheme, the levels of irreversible demagnetization in various regions throughout the entire volume of each PM are evaluated using 3 dimensional (3D) finite elements analysis (3D FEA) in full loading condition during startup until reaching steady state. Based on the results of these analyses, the primitive structural scheme is then modified through segmenting (cutting into four pieces) each PM from where the worst irreversible demagnetization levels occurred.

As will be demonstrated by the results of 3D FEA, the proposed modified structure is not only capable of successful startup and synchronization of the motor but also it considerably reduces the PM demagnetization level. Thus, the performance of the motor is significantly improved.

The demagnetization of PMs is an important effect in PM synchronous motors, which can greatly affect motor performance. Therefore, it is necessary to be considered in the motor design processes. This effect becomes much more significant in the line-start PM motors because the usual high-magnitude startup induction current produces a strong armature-reaction magnetic field, which may cause the PMs to be irreversibly demagnetized. The approach proposed in this paper provides a structural solution to mitigate the PM demagnetization effect and thereby improve the performance of an LSAFPM motor through modifying the structure of the LSAFPM motor according to an FEA-based PM demagnetization analysis. As a considerable contribution, in this analysis, the variation of demagnetization level between different areas inside each PM is computed and is considered as a basis for proposing an appropriate structural modification to mitigate the PM demagnetization effect as much as possible.

The great value of offline identification of machine parameters is when the machine manufacturer does not provide its parameters. Most machine control strategies require parameter values, and some circumstances in the industrial sector only require offline identification. This paper aims to present a new offline method for estimating induction motor parameters based on least squares and a salp swarm algorithm (SSA).

The central concept is to use the classic least squares (LS) method to acquire the majority of induction machine (IM) constant parameters, followed by the SSA method to obtain all parameters and minimize errors.

The obtained results showed that the LS method gives good results in simulation based on the assumption that the measurements are noise-free. However, unlike in simulations, the LS method is unable to accurately identify the machine’s parameters during the experimental test. On the contrary, the SSA method proves higher efficiency and more precision for IM parameter estimation in both simulations and experimental tests.

After performing a primary identification using the technique of least squares, the initial intention of this study was to apply the SSA for the purpose of identifying all of the machine’s parameters and minimizing errors. These two approaches use the same measurement from a simple running test of an IM, and they offer a quick processing time. Therefore, this combined offline strategy provides a reliable model based on the identified parameters.

The purpose of this article is to treat the nonlinear optimal control problem in EV traction systems which are based on 5-phase induction motors. Five-phase permanent magnet synchronous motors and five-phase asynchronous induction motors (IMs) are among the types of multiphase motors one can consider for the traction system of electric vehicles (EVs). By distributing the required power in a large number of phases, the power load of each individual phase is reduced. The cumulative rates of power in multiphase machines can be raised without stressing the connected converters. Multiphase motors are also fault tolerant because such machines remain functional even if failures affect certain phases.

A novel nonlinear optimal control approach has been developed for five-phase IMs. The dynamic model of the five-phase IM undergoes approximate linearization using Taylor series expansion and the computation of the associated Jacobian matrices. The linearization takes place at each sampling instance. For the linearized model of the motor, an H-infinity feedback controller is designed. This controller achieves the solution of the optimal control problem under model uncertainty and disturbances.

To select the feedback gains of the nonlinear optimal (H-infinity) controller, an algebraic Riccati equation has to be solved repetitively at each time-step of the control method. The global stability properties of the control loop are demonstrated through Lyapunov analysis. Under moderate conditions, the global asymptotic stability properties of the control scheme are proven. The proposed nonlinear optimal control method achieves fast and accurate tracking of reference setpoints under moderate variations of the control inputs.

Comparing to other nonlinear control methods that one could have considered for five-phase IMs, the presented nonlinear optimal (H-infinity) control approach avoids complicated state-space model transformations, is of proven global stability and its use does not require the model of the motor to be brought into a specific state-space form. The nonlinear optimal control method has clear implementation stages and moderate computational effort.

In the transportation sector, there is progressive transition to EVs. The use of five-phase IMs in EVs exhibits specific advantages, by achieving a more balanced distribution of power in the multiple phases of the motor and by providing fault tolerance. The study’s nonlinear optimal control method for five-phase IMs enables high performance for such motors and their efficient use in the traction system of EVs.

Nonlinear optimal control for five-phase IMs supports the deployment of their use in EVs. Therefore, it contributes to the net-zero objective that aims at eliminating the emission of harmful exhaust gases coming from human activities. Most known manufacturers of vehicles have shifted to the production of all-electric cars. The study’s findings can optimize the traction system of EVs thus also contributing to the growth of the EV industry.

The proposed nonlinear optimal control method is novel comparing to past attempts for solving the optimal control problem for nonlinear dynamical systems. It uses a novel approach for selecting the linearization points and a new Riccati equation for computing the feedback gains of the controller. The nonlinear optimal control method is applicable to a wider class of dynamical systems than approaches based on the solution of state-dependent Riccati equations.

Mentoring processes and relationships can prove crucial to teachers in the initial phases of the teacher education continuum. Limited research exists regarding mentoring in further education and training (FET) in Ireland. This paper attempts to address this gap, illuminating and unpacking the “mentoring stories” of five teachers in FET.

The overall project adopted a narrative approach. Data were collected via in-depth interviews, part of which clearly focussed on participants' lived experience of mentoring. Thematic analysis revealed four overarching themes.

The themes reveal a spectrum of practices and perspectives on the role of mentors. There are ample instances of collegiality, mutual respect and an appreciation of the professional life stage of the mentee. However, evidently a lack of understanding of who mentors are and what they do persists, leading to some informal approaches and opening up the potential for misinterpretation and misalignment.

This paper sheds light on an area of FET practice that has been relatively unseen before now. It gives voice to those who have experienced mentoring in the Irish FET sector that, to a degree, has seen structural and attitudinal transformations in recent times.

This paper aims to consider the practices and experiences of the new school-based mentors for Early Career Teachers (ECT's), emerging from the UK Government's new early career framework (ECF) policy (DfE, 2019a). The paper uses Lipsky's (2010) framing of professionals as “street level bureaucrats” to consider the extent to which the ECT mentors, as new policy actors, exercise professional discretion (Lipsky, 2010) in negotiating and aligning the new ECF policy with existing practice.

To research the mentor's interpretation and enactment of the new ECF policy, semi structured interviews were undertaken with an initial sample of nine mentors and four induction tutors who were also mentors. Online semi structured interviews were held, lasting around 50 min. This method was largely pragmatic as the study started during a period when schools were still cautious of face-to-face visitors in terms of COVID-19. Although the benefits for the interviewer experiencing the culture and context in which the ECT mentor was situated were lost, offering online interviews was critical in securing mentors' time.

Findings suggest a disconnect between the intentions of the policy and the reality of its enactment at a local level. The ECT mentors have limited professional discretion, but some are exercising this in relation to their own professional development and the training they are providing for their ECTs. Most of the mentors are adapting the ECT's professional development journey whilst mindful of the programme requirements. The degree to which the ECT mentors used professional discretion was linked and limited largely by their own levels of confidence and experience of mentoring, and to a lesser extent the culture of their schools.

The ECF policy represents an important step in acknowledging the need to professionally develop mentors for the work they undertake supporting beginning teachers. However, the time and the content of the mentor training have not been given sufficient attention and remains a hugely missed opportunity. It does not appear to be recognised by the government policy makers but more significantly and concerning in this research sample it is not being recognised sufficiently by those mentoring the ECTs themselves.

There is an urgent need by the UK government and school leaders to understand the link between the quality of mentor preparation and the quality of the ECTs who will be entering the profession and influencing the quality of education in future years. More time and resourcing need to be focussed on the professional development of mentors enabling them to exercise professional discretion in increasingly sophisticated ways in relation to the implementation of the ECF policy.

The ECF policy is the latest English government response to international concerns around the recruitment and retention of teachers. The policy mandates for a new policy actor: the ECT mentor, responsible for the support and professional development of beginning teachers. The nature of the mentor's role in relation to the policy is emerging and provides an interesting case study in the disconnect between the intentions of a policy and its initial enactment on the ground. The mentors may be viewed as street level bureaucrats exercising degrees of professional discretion as they interpret the policy in their own school context.

This paper aims at developing an improved method, based on binary search algorithm (BSA) for the steady-state analysis of self-excited induction generators (SEIGs), which are increasingly used in wind energy electric conversion systems. The BSA is also compared with linear search algorithm (LSA) to bring out the merits of BSA over LSA.

All the parameters of SEIG, including the varying core loss of the machine, have been considered to ensure accuracy in the predetermined performance values of the set up. The nodal admittance method has been adopted to simplify the equivalent circuit of the generator and load. The logic and steps involved in the formulation of the complete procedure have been illustrated using elaborate flowcharts.

The proposed approach is validated by the experimental results, obtained on a three-phase 240 V, 5.0 A, 2.0 kW SEIG, which closely match with the corresponding predicted performance values. The analysis is shown to be easy to implement with reduced computation time.

A novel improved and simplified technique has been formulated for estimating the per unit frequency (a), magnetizing reactance (X_m) and core loss resistance (R_m) of the SEIG using the nodal admittance of its equivalent circuit. The accuracy of the predetermined performance is enhanced by considering the SEIG’s varying core loss. Only simple MATLAB programming has been used for adopting the algorithms.

The purpose of this study is to calculate the normal force of a two degree of freedom direct drive induction motor considering coupling effects based on an analytical model. Compared with the traditional single degree of freedom motor, normal force characteristics of two-degree-of-freedom direct drive induction motor (2DOFDDIM) is affected by coupling effect when the machine is in a helical motion. To theoretically explain the influence mechanism of coupling effect, this paper conducts a quantitative analysis of the influence of coupling effect on normal force based on the established analytical model of normal force considering coupling effect.

Firstly, the normal forces generated by 2DOFDDIM in linear motion, rotary motion and helical motion are investigated and compared to prove the effect of the coupling effect on the normal force. During this study, several coupling factors are established to modify the calculation equations of the normal force. Then, based on the multilayer theoretical method and Maxwell stress method, a novel normal force calculation model of 2DOFDDIM is established taking the coupling effect into account, which can easily calculate the normal force of 2DOFDDIM under different motions conditions. Finally, the calculation results are verified by the results of 3D finite element model, which proves the correctness of the established calculating model.

The coupling effect produced by the helical motion of 2DOFDDIM affects the normal force.

In this paper, the analytical model of the normal force of 2DOFDDIM considering the coupling effect is established, which provides a fast calculation for the design of the motor.