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The optimization of the cross section of an axisymmetric induction heating device is performed by means of genetic algorithms (GAs).

The hybrid finite element method–Dirichlet boundary condition iteration method is used to deal with the unbounded nature of the field. The formulation of the electromagnetic problems takes into account skin and proximity effects in the source currents.

The convergence of GAs towards the optimum is very fast, since less than a thousand analyses have been necessary.

A special derivation of the finite element global system is presented which allows us to save computing time.

The purpose of this paper is to compare the hybrid FEM-BEM and FEM-DBCI methods for the solution of open-boundary static and quasi-static electromagnetic field problems.

After a brief review of the two methods (both coupling a differential equation for the interior problem with an integral equation for the exterior one), they are compared in terms of accuracy, memory and computing time requirements by means of a set of simple examples.

The comparison suggests that FEM-BEM is more accurate than FEM-DBCI but requires more computing time.

Then FEM-DBCI appears more appropriate for applications which require a shorter computing time, for example in the stochastic optimization of electromagnetic devices. Conversely, FEM-BEM is more appropriate in cases in which a high level of precision is required in a single computation.

Note that the FEM-BEM considered in this paper is a non standard one in which the nodes of the normal derivative on the truncation boundary are placed in positions different from those of the potential.

The purpose of this paper is to present a modified version of the hybrid Finite Element Method-Dirichlet Boundary Condition Iteration method for the solution of open-boundary skin effect problems.

The modification consists of overlapping the truncation and the integration boundaries of the standard method, so that the integral equation becomes singular as in the well-known Finite Element Method-Boundary Element Method (FEM-BEM) method. The new method is called FEM-SDBCI. Assuming an unknown Dirichlet condition on the truncation boundary, the global algebraic system is constituted by the sparse FEM equations and by the dense integral equations, in which singularities arise. Analytical formulas are provided to compute these singular integrals. The global system is solved by means of a Generalized Minimal Residual iterative procedure.

The proposed method leads to slightly less accurate numerical results than FEM-BEM, but the latter requires much more computing time.

Then FEM-SDBCI appears more appropriate than FEM-BEM for applications which require a shorter computing time, for example in the stochastic optimization of electromagnetic devices.

Note that FEM-SDBCI assumes a Dirichlet condition on the truncation boundary, whereas FEM-BEM assumes a Neumann one.

This paper aims to extend an efficient method to solve the global system of linear algebraic equations in the hybrid finite element method – boundary element method (FEM‐BEM) solution of open‐boundary skin effect problems. The extension covers the cases in which the skin effect problem is set in a truncated domain in which no homogeneous Dirichlet conditions are imposed.

The extended method is based on use of the generalized minimal residual (GMRES) solver, which is applied virtually to the reduced system of equations in which the unknowns are the nodal values of the normal derivative of the magnetic vector potential on the fictitious truncation boundary. In each step of the GMRES algorithm the FEM equations are solved by means of the standard complex conjugate gradient solver, whereas the BEM equations are not solved but used to perform fast matrix‐by‐vector multiplications. The BEM equations are written in a non‐conventional way, by making the nodes for the potential non‐coinciding with the nodes for its normal derivative.

The paper shows that the method proposed is very competitive with respect to other methods to solve open‐boundary skin effect problems.

The paper illustrates a new method to solve efficiently skin effect problems in open boundary domains by means of the hybrid FEM‐BEM method.

Gives introductory remarks about chapter 1 of this group of 31 papers, from ISEF 1999 Proceedings, in the methodologies for field analysis, in the electromagnetic community. Observes that computer package implementation theory contributes to clarification. Discusses the areas covered by some of the papers ‐ such as artificial intelligence using fuzzy logic. Includes applications such as permanent magnets and looks at eddy current problems. States the finite element method is currently the most popular method used for field computation. Closes by pointing out the amalgam of topics.

The purpose of this study is to investigate whether and how inter-firm cooperation and firm age moderate the relationship between family ownership and productivity.

We first estimate the total factor productivity (TFP) of a large sample of Italian firms observed over the period 2010–2018 and then apply a Poisson random effects model.

TFP is, on average, higher for non-family firms (non-FFs) than for FF. Furthermore, inter-organizational cooperation and firm age mitigate the negative effect of family ownership. In detail, it is found that belonging to a network acts as a moderator in different ways according to firm age. Indeed, young FFs underperform non-FF peers, although the TFP gap decreases with age. In contrast, the benefits of a formal network are high for older FFs, suggesting that an age-related learning process is at work.

The study provides evidence that FFs can outperform non-FFs when they move away from Socio-Emotional Wealth-centered reference points and exploit knowledge flows arising from high levels of social capital. In the case of mature FFs, networking is a driver of TFP, allowing them to acquire external resources. Since FFs often do not have sufficient in-house knowledge and resources, they must be aware of the value of business cooperation. While preserving the familiar identity of small companies, networks grant FFs the competitive and scale advantages of being large.

Despite the wide but ambiguous body of research on the performance gap between FFs and non-FFs, little is known about the role of FFs’ heterogeneity. This study has proven successful in detecting age as a factor in heterogeneity, specifically to explain the network effect on the link between ownership and TFP. Based on a representative sample, the study provides a solid framework for FFs, policymakers and academic research on family-owned companies.

This paper investigates whether and to what extent operating in inner areas affects the profitability of innovative Italian small and medium-sized enterprises (SMEs) over 2012–2018.

Guided by the National Strategy for Inner Areas and the “Investment Compact,” this study distinguishes between inner and core innovative SMEs. It employs various econometric models to estimate a regression for the return on assets of SMEs, differentiating between firms operating in inner and non-inner areas of northwest, northeast, centre and south Italy.

Findings reveal that innovative SMEs in inner areas generally exhibit lower profitability compared to those in non-inner municipalities. However, huge heterogeneity in results is observed across the country. Specifically, innovative SMEs in the inner areas of the south register lower profitability than those operating in non-inner zones. Conversely, innovative SMEs located in the inner municipalities of northwest and northeast Italy show higher profitability than their peers in non-inner areas. The results imply that targeted policies for inner areas are crucial. However, due to the diversity of local impacts, a differentiated approach, depending on the geographic context, is necessary.

The study aims to explore the relationship between inner areas and the performance of innovative SMEs in Italy. More precisely, it examines the effect of operating in a municipality located within an inner area on the profitability of innovative SMEs. This issue has been overlooked in existing literature. Importantly, we aim to determine whether there is a heterogeneous impact based on geographical localisation, specifically in the Northwest, the Northeast, the Centre and the South of the country. Therefore, this paper contributes to the literature by investigating the factors influencing the performance of innovative SMEs and suggesting new policy recommendations for developing inner areas in Italy.

The hospitality industry is responsible for significant amounts of waste, more than one-third of which is food waste. Through the comparison between an Italian and a Romanian hotel, this paper aims to provide a better understanding of food waste management trends in the hotel industry as well as to highlight hotel kitchens and hotel food services weaknesses and opportunities to minimize food waste.

In-depth interviews, personal communication and observations were conducted to investigate food service planning, food procurement and food waste management, as well as to better comprehend current individuals’ understanding and attitudes, infrastructures, legislative culture and opportunities either from the managerial and the employees’ perspective. Data were analyzed according to a content analysis approach.

Three critical hot spots emerged from the analysis: prediction and check of guests’ attendance, communication and transparency with local suppliers and among departments within the unit and purchasing frequency and perishable food provisioning. The accurate forecasting of the number of guests and their nationality is fundamental in avoiding food waste at food service, as well as implementing transparency and communication with local suppliers.

Although academia and authorities have recognized the crucial importance of food waste management, food waste research in the hotel industry remains under-researched. The present exploratory research contributes to the scarce empirical studies about hotels’ food waste, giving theoretical and managerial recommendations for supporting further studies, highlighting the need for formal deals between hotels and local suppliers (food procurement), as well as the importance of food-networks that holds together companies, retailers and charities (food donation).