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Inverse problems in electromagnetism, namely, the recovery of sources (currents or charges) or system data from measured effects, are usually ill-posed or, in the numerical formulation, ill-conditioned and require suitable regularization to provide meaningful results. To test new regularization methods, there is the need of benchmark problems, which numerical properties and solutions should be well known. Hence, this study aims to define a benchmark problem, suitable to test new regularization approaches and solves with different methods.

To assess reliability and performance of different solving strategies for inverse source problems, a benchmark problem of current synthesis is defined and solved by means of several regularization methods in a comparative way; subsequently, an approach in terms of an artificial neural network (ANN) is considered as a viable alternative to classical regularization schemes. The solution of the underlying forward problem is based on a finite element analysis.

The paper provides a very detailed analysis of the proposed inverse problem in terms of numerical properties of the lead field matrix. The solutions found by different regularization approaches and an ANN method are provided, showing the performance of the applied methods and the numerical issues of the benchmark problem.

The value of the paper is to provide the numerical characteristics and issues of the proposed benchmark problem in a comprehensive way, by means of a wide variety of regularization methods and an ANN approach.

This study aims to investigate the possible use of a deep neural network (DNN) as an inverse solver.

Different models based on DNNs are designed and proposed for the resolution of inverse electromagnetic problems either as fast solvers for the direct problem or as straightforward inverse problem solvers, with reference to the TEAM 25 benchmark problem for the sake of exemplification.

Using DNNs as straightforward inverse problem solvers has relevant advantages in terms of promptness but requires a careful treatment of the underlying problem ill-posedness.

This work is one of the first attempts to exploit DNNs for inverse problem resolution in low-frequency electromagnetism. Results on the TEAM 25 test problem show the potential effectiveness of the approach but also highlight the need for a careful choice of the training data set.

The purpose of this paper is to evaluate the worst-case behavior of a given electronic circuit by varying the values of the components in a meaningful way in order not to exceed pre-defined currents or voltages limits during a transient operation.

An analytic formulation is used to identify the time-dependent solution of voltages or currents using proper state equations in closed form. Circuits with linear elements can be described by a system of differential equations, while circuits composing nonlinear elements are described by piecewise-linear models. A sequential quadratic program (SQP) is used to find the worst-case scenario.

It is found that the worst-case scenario can be obtained with as few solutions to the forward problem as possible by applying an SQP method.

The SQP method in combination with the analytic forward solver approach shows that the worst-case limit converges in a few steps even if the worst-case limit is not on the boundary of the parameters.

The purpose of this study is to verify how the carbon doping of the WC-Co cemented carbide (CC) affected their structure before their processing by hot isostatic pressing (HIP) technology.

The samples for this experiment were fabricated by selective laser melting technology (SLM) using a YAG fiber laser with a power of P = 40 W and a scanning speed of 83 mm/s. The subsequent carbon doping process was performed in a chamber furnace at 900 0 C for 1, 4 and 12 h. The HIP was performed at 1,390°C and pressures of 40 MPa, 80 MPa and 120 MPa. The changes induced in the structures were evaluated using X-ray diffraction and various microscopic methods.

X-ray diffraction analysis showed that the structure of the samples after SLM consisted of WC, W₂C, Co₄W₂C and Co phases. As a result of the increase in the carbon content in the structure of the samples, the transition carbide W₂C and structural phase Co₄W₂C decayed. Their decay was manifested by the coarsening of the minor alpha phase (WC), which occurred both during the carburizing process and during the subsequent processing using HIP. In the samples in which the structure was carburized prior to HIP, only the structural phases WC and Co were observed in most cases.

The results confirm that it is possible to increase the homogeneity of the CC structure and thus its applicability in practice by additional carburization of the sample structure with subsequent processing by HIP technology.

Banks play a crucial role in the sustainable development of exports as they finance much of the trade. Additionally, in Brazil's case, banks provide exporting companies with advisory and training services, which facilitate the internationalization process. This work aims to analyze the role of public and private banks in the export process of companies in Brazil.

Interviews are conducted with a sample of 318 Brazilian exporting companies. Two research questions are posed: What type of export services do companies use from public and private banks in Brazil? Is exporting companies' access to credit, as a type of banking service, related to their size or export experience? A descriptive study of the functions of public and private banks in helping Brazilian exports is presented. Hypotheses are proposed regarding companies' access to credit and its relationship with their size and export experience.

It is found that public and private banks in Brazil provide exporting companies with banking services, other services related to technical aspects, and export consulting. There are significant differences in access to credit in both public and private banks, depending on the exporting company's size.

This work contributes to the internationalization literature on the role of banks in supporting exports in an emerging country like Brazil.

Recent research has demonstrated that people are more likely to engage with fatty food content online. One way health advocates might facilitate engagement with healthier, calorie-light foods is to alter how people process food media. This research paper aims to investigate the moderating role of viewer mindset on consumer responses to digital food media.

Two experiments were conducted by manipulating the caloric density of food media content and/or one’s mindset before viewing.

Results show that the relationship between nutrition and engagement is moderated by consumer mindset, where activating a more calculative mindset before exposure can elevate social media engagement for calorie-light food media content.

These findings contribute to the domain of obesogenic digital environments and the role of nutrition in consuming food media. By examining how mindsets interact with affective evaluations, this work demonstrates that a default mindset based on instinct can be shifted and thus alter subsequent behavioral intentions.

This work provides insight into what can boost the visibility and engagement of healthy food content on social media. Marketers can help promote healthier food media by cueing consumers to think more deliberately before exposure.

This research builds on recent work by demonstrating how to boost engagement with healthy foods on social media by cueing a more thoughtful mindset.

The use of digital technologies in the financial service industry has brought new complexities to the corporate governance in banks. Relying on the agency perspective of the shareholder, debtholder and societal governance in banks, this research examines the impact of financial technology innovation (FinTech) on banks' performance by enlightening the monitoring role of female independent directors.

Relying on a sample of Italian banks observed during the period 2016–2020, the authors hand-collected data on the use of FinTech by considering (1) the in-house provisions of FinTech solutions, (2) the collaboration with external FinTech firms and (3) a combination of both measures. The authors run a panel data regression analysis with fixed effects, measuring bank performance through bank competitiveness and bank riskiness.

The authors find that FinTech increases bank competitiveness in gathering money from depositors and that independent women on board mitigate the negative relationship between FinTech and the riskiness of banks' assets, ameliorating the conflicting interests among shareholders, debtholder and societal governance.

This study emphasizes the complexities of bank governance when dealing with FinTech in the wider perspective of equity governance, debt governance and the societal governance spotlighting the importance of appointing female directors in independent positions to enhance the bright sides of financial innovation. The authors enrich the literature on FinTech with a finer understanding of the drivers and implications of in-house provisions of FinTech solutions versus the collaboration with external FinTech firms.

The purpose of this study is to develop and empirically test a lovemark measure that can be used to identify how brands of wireless-enabled computing devices are classified based on customers’ respect and love toward them.

On evidence drawn from 1,016 consumers of wireless-enabled computing devices (e.g. netbooks and tablets) in Greece, partial least squares method is used to test the validity of the proposed hierarchical model.

Results show that a lovemark measure can be conceptualized as a third-order reflective construct having respect and love as its second-order dimensions. In turn, respect reflects on brand performance, trust and reputation, and love reflects on brand commitment, intimacy and passion. The proposed measure presents a very good external validity as it can explain big portions of variance in consumer responses including repurchase intentions, positive WOM and willingness to pay a price premium. Finally, the proposed measure is used to classify eight well-known devices as products, fads, brands and lovemarks and identify the love styles associated with brand relationships.

This paper provides empirical evidence for measuring and identifying lovemarks using a hierarchical model, which can be further used to develop a more effective strategy for managing the functional and emotional aspects of brands to strengthen consumer-brand relationships.

El objetivo de este estudio es el desarrollo metodológico y validación empírica de una escala para clasificar las marcas de productos tecnológicos en base a las dos dimensiones que caracterizan a las marcas Lovemark: el respecto y amor.

Con una base de datos recogidos de una muestra de 1.106 consumidores de productos tecnológicos (e.g., tablets y portátiles pequeños) en Grecia, se usa PLS para testar la validez del modelo jerárquico propuesto.

Los resultados ponen de manifiesto que el concepto Lovemark puede ser conceptualizado como un constructo reflectivo de tres dimensiones siendo el respeto y el amor hacia la marca las dimensiones de segundo orden. A su vez, el respeto hacia la marca refleja el desempeño, la confianza y reputación de la marca mientras que el amor queda reflejado en conceptos tales como el compromiso, la intimidad y la pasión. La medida propuesta presenta una aceptable validez externa pues es capaz de explicar mayor porcentaje de la varianza de las intenciones de compra, la comunicación boca-oreja positiva y la disposición a pagar un mayor precio por la marca. Finalmente, se demuestra la utilidad de la medida propuesta para clasificar ocho marcas conocidas según los niveles de amor y respeto que los consumidores manifiestan hacia las mismas así como identificar los estilos de amor asociados a la relación que los consumidores mantienen con estas marcas.

Este trabajo ofrece evidencias empíricas para medir e identificar las Lovemark usando un modelo jeráquico que puede ser utilizado posteriormente para desarrollar una estrategia más efectiva en la gestión de los aspectos funcionales y emocionales de las marcas como medio para fortalecer las relaciones marca-consumidor.