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The purpose of this paper is to present a new approach to drive the excitation field sources in the eddy current testing (ECT) of tubular conductive structures.

The magnetic field used for ECT is generated by pairs of counter‐series connected coils, driven by AC currents. The phase and amplitude of the currents is electronically controlled in order to shape the primary field map, allowing circumferential sweeps until the presence of defects is detected, and then “focusing” the field on the defective section of the tube, increasing in this way the sensibility of the ECT probes in the targeted area, in order to determine with higher precision, the position, and the shape of the defect.

If suitably designed, the field measurement system allows to enable/disable a number of probes to enhance the resolution in the defect area while keeping low the number of required data channels.

The analyzed geometry is limited to circular‐shaped tubes, of infinite extent. Future work should be on the extension of the methodology to general shapes, and to finite length cylinders.

The proposed method allows to enhance resolution in ECT of tubes at the end of production lines, guaranteeing a first, simple yet effective quality assessment of tubes in industrial environments.

The paper presents a new technique to test conductive tubes using fixed excitation system, but allowing to focus magnetic field in defective regions. The method could be helpful for industrial diagnostics.

The role of the parameters uncertainness in the optimal design of electromagnetic devices is discussed and an efficient strategy to look for robustness of feasible solutions is proposed. A suitable modification of the objective function (OF) is used to rank different device configurations on the basis of their ability to maintain the required performances against small parameters modifications due to construction tolerances. In the frame of a genetic algorithm approach, the modified OF has been able to address the evolutionary optimisation towards more robust solutions.

The paper aims to illustrate a numerical technique to calculate fields and inductances of rotating electrical machines.

The technique is based on an integral formulation of the nonlinear magnetostatic model in terms of the unknown magnetization. The solution is obtained by means of a Picard-Banach iteration whose convergence can be theoretically proved.

The proposed method has been used to build a model of a large turbine generator. In particular, the influence of end effects on flux linkages has been computed. It has been demonstrated that the 2D solution underestimates the flux linkages as well as the no load voltage of 2 per cent, while the leakage fluxes are computed by the 2D solution with errors as high as 20 per cent.

The method is advantageous in comparison to standard methods.

The purpose of this paper is to present the use of the compensation theorem (CT), well known in the analysis of linear electric networks, to compute sensitivity of the performance functions used in the robust design or tolerance analysis of electromagnetic devices.

The CT is first illustrated in the case of a simple field analysis problem. Then, using numerical simulations, the effectiveness of compensation approach for assessing impact of the small modification of material properties is shown. The numerical simulations are performed with a finite elements code based on an integral formulation.

The complexity of additional computations to assess the effect of small variations involved in sensitivity analysis can be reduced.

The method can be applied only to linear systems; in addition, although compensation applies to any variations, the reduction of computational complexity is achieved only for small variations, giving localized effects.

The method proposed in the paper can speed up the computations of sensitivity arrays in the robust design and tolerance analysis of electromagnetic device, when numerical methods are applied.

The use of CT in field computations is not new, but its adoption in the sensitivity computation is new to the best knowledge of authors.

A new method for the numerical computation of the dynamic behaviour of electro‐dynamic loudspeakers is presented. The numerical scheme, based on the finite element method (FEM), allows the simulation of coupled magnetic, mechanical and acoustic fields. The obtained simulation results are in good agreement with measured data.

A simple model is proposed for the analytical calculation of the eddy current induced by a time‐varying magnetic field in a conductive plate. It is assumed that the current is uniformly distributed over the plate thickness and circulates in rectangular paths. The plate is considered as an equivalent LR circuit and its equivalent inductance and resistance are calculated analytically and expressed as a function of the plate dimensions. The analytical solution of the equation, governing the LR circuit, yields the total current circulating in the plate as a function of time. The model is applied to a well known benchmark problem and the results are in good agreement with those obtained by experiment.

The purpose of this paper is to explore older people’s food consumption experiences. Specifically, the paper seeks to provide understanding on the influence of food intake on consumer vulnerability and how this manifests within people’s lives.

The study adopts an interpretive, exploratory approach, using in-depth interviews with 20 older consumers in the UK. Thematic analysis is conducted, establishing patterns and contradictions with the data.

The findings demonstrate how biological, psychological and social age-related changes can contribute to reduced food intake in later life. The loss of control over one’s consumption experiences as a result of inappropriate portion sizes acts as a source of both immediate and future vulnerability. Resultant food wastage can serve as an immediate reminder of negative associates with ageing, while the accumulative effect of sustained under-consumption contributes to increased frailty. As a result, consumer vulnerability can pervade other contexts of an individual’s life.

The research reveals opportunities for firms to use packaging development to reduce experiences of consumer vulnerability through reduced apportionment of packaged food products. However, this needs to be considered within a multi-demographic marketplace.

This paper contributes to literature by providing a unique lens with which to understand consumer vulnerability. The findings offer a developmental perspective on the experience of consumer vulnerability, revealing the stages of proximate, immediate, intermediate and ultimate vulnerability. This perspective has the potential to offer more detailed, nuanced insights into vulnerability in other contexts beyond food consumption.

The identification of magnetic field profiles is crucial in many applications where a direct measurement is difficult. We discuss here a technique, based on the injection of charged particles in the region under examination, which promises to be an innovative and effective tool in the analysis of 1‐D field profiles in high current plasma discharges. After the decription of the inverse problem related to the field construction, we consider a suitable discrete identification scheme, and analyze some properties of the latter. The field map in the interest region is reconstructed via a minimization procedure, which identifies the coefficient of a well‐suited expansion for the field. In particular, we discuss the precision and robustness of the identification procedure, with respect to the chosen optimization scheme, the amount of data, the order in the field expansion, and the influence of noise on the data.

The health-care services in Iraq currently face many challenges. The most noted is the lack of effective nursing leaders to meet the growing needs of the health-care services. Effective nursing leadership is critical to the health-care system, affecting work performance, quality of care and staff satisfaction. The literature suggests that nursing leaders in Iraq are not adequately trained to provide leadership to improve the nursing profession and have limited involvement in decision-making. The purpose of this study is to explore the views of nurses on what they believe constitutes effective leadership in Iraq.

A qualitative methods approach is used involving 20 semi-structured interviews of senior nurses. The sample of nurses came from two large general hospitals in Iraq. The qualitative data was thematically analyzed and interpreted.

The study results indicated that there were factors that influence the performance of nurse leader, namely, excessive workload, personal relationship with nursing staff, professional recognition of nursing and selection criteria of leaders. Test results show that there were significant differences in views of the nurses toward nurse leaders’ performance. This research concludes that the nurse leader performance in developing countries is affected by excessive workload, personal relationship with nursing staff, professional recognition of nursing and selection criteria of leaders.

The relevance of the study stems from the scarcity of research on the leader performance in developing countries, while studies on the factors influencing the innovative performance of leaders in nurses’ professional are significantly limited. This study is one of the earliest studies that investigate these factors influencing the nurse leader’s performance.

This paper aims to develop a methodology for progressive finite element (FE) modeling of transformers, from simple to complex models of both magnetic cores and windings.

The progressive modeling of transformers is performed via a subproblem (SP) FE method. A complete problem is split into SPs with different adapted overlapping meshes. Model refinements are performed from ideal to real flux tubes, one-dimensional to two-dimensional to three-dimensional models, linear to nonlinear materials, perfect to real materials, single wire to volume conductor windings and homogenized to fine models of cores and coils, with any coupling of these changes.

The proposed unified procedure efficiently feeds each SP via interface conditions (ICs), which lightens mesh-to-mesh sources transfers and quantifies the gain given by each refinement on both local fields and global quantities, with a clear view on its significance to justify its usefulness, if any. It can also help in education with a progressive understanding of the various aspects of transformer designs.

Models of different accuracy levels are sequenced with successive additive corrections supported by different adapted meshes. The way the sources act at each correction step, up to the full models with their actual geometries, is given a particular care and generalized, allowing the proposed unified procedure. For all the considered corrections, the sources are always of IC type, thus only needed in layers of FE along boundaries, which lightens the required mesh-to-mesh projections between subproblems.