Abstract
In this article, a novel topology generalization of a current source converter (CSC) that allows controlling of multiple single-phase ac converters independently sharing the same dc-bus, with the advantage of having a reduced number of conducting switches and a lower dc-bus current, is presented. A conventional n-output/port single-phase CSC that uses the same dc-bus needs to have n H-bridge converters connected in series, which means that it always has 2n conducting switches. The new topology allows generating any n ac output currents always having only (n + 1) conducting switches in a switching period. This represents (1 - 1/n). 50% less conduction losses when compared with the equivalent conventional multiport single-phase CSC. A scalar pulsewidth modulation to control the converters with switching optimization and its generalization is also presented. Details of topology, control strategy, and modulation are presented. Simulation and experimental results are provided to validate the theoretical approach.

Abstract
The issue of population ageing is no longer exclusively centred on developed countries. Empirical studies have proven that the rise in the proportion of the older age group has been already visible in the least developed countries (LDCs). The primary concern of population ageing in LDCs is that ageing is approaching LDCs even faster than approaching developing and developed countries. We found that despite the common factors such as human capital development, female participation in the labour market and economic growth, the annual growth rate of the ageing of LDCs highly depends on international aids (health care and development) and the rising number of emigrations over the working-age population. Our empirical results suggest that the existence of the ageing population in LDCs determine by the involvement of international bodies in supporting the welfare system of the country and the policy initiatives of developed countries in attracting migrant workers of LDCs to overcome the ageing problem in their countries.

Abstract
Gender issues are increasingly studied in entrepreneurship along with the debate about the centrality of resilience in both individuals and organizations. However, the analysis of entrepreneurial initiative based on genderized resilience is a novel insight. Prior studies point out that, against the odds, in more vulnerable environments, individuals tend to be more resilient and exhibit higher levels of entrepreneurial initiative. Considering previous studies and its remarks about the importance of self-efficacy, self-determination, self-regulation, and social environment to determine a resilient profile, this work bridges the existing theoretical contributions with empirical findings, using resilience and entrepreneurship as the ground research field. Empirical results evidence the role of resilience and opens the discussion around its importance through a genderized perspective along with its effect on the entrepreneurial initiative. The existence of a gendered connection between individual resilience and entrepreneurial initiative emerges as a relevant insight. These findings provide valuable information to policymakers and practitioners understanding and designing policy packages which better suit gender singularities. © 2021, The Author(s), under exclusive license to Springer Nature Switzerland AG.

Abstract
This paper addresses the concept of Industry 4.0 from the perspective of the molds industry, a key industry in today's industrial panorama. With its constant modernization, several technologies have been introduced, in particular regarding machining equipment. With each brand and model requiring different (proprietary) interfaces and communication protocols, this technological diversity renders the automatic interconnection with production management software extremely challenging. In this paper a methodology to build monitoring solutions for machining devices is defined, based on the main equipment and operations used by molds industry companies. For a standardized approach, OPC UA is used for high-level communication between the various systems. As a key result of this paper, and given the variety of monitoring systems and communication protocols, the developed approach combines various different machine interfaces on a single system, in order to cover a relevant subset of machining equipment currently in use by the molds industry. This kind of all-in-one approach will give production managers access to the information needed for a continuous monitoring and improvement of the entire production process. (C) 2021 The Authors. Published by Elsevier B.V.

Abstract
Cathodal transcranial direct current stimulation (c-tDCS) is a non-invasive option for treatment of refractory epilepsy. However, it is still unknown whether this therapy has a positive stabilizing effect on the vegetative function of these patients. Heart Rate Variability (HRV) is considered an efficient tool to monitor the cardiac autonomic system, which has been correlated with the risk of Sudden Unexpected Death in Epilepsy (SUDEP). In this study, changes in HRV are investigated after c-tDCS of six patients (34.50 +/- 11.10 years) with refractory epilepsy, which have been selected at the University Hospital, LMU Munich. Patients were categorized as responders (n=2), non-responders (n=3) and uncategorized (n=1). We analyzed 24 hours of electrophysiological data recorded before and after treatment, and computed HRV metrics (AVNN, SDNN, RMSD, pNN20, pNN50, LH/HF, 0V, 1V, 2LV, 2UV, SD1 and SD2). All patients revealed a change in almost all HRV metrics post stimulation. Grouped all patients, there was a significant (p<0.05) change in RMSSD, pNN50, SD1 and LH/HF. For responders there was an increase in all time domain and nonlinear metrics, which was not seen for non-responders. These results suggest that tDCS exerts significant changes in cardiovascular autonomic system in patients with refractory epilepsy. HRV metrics may also serve as biomarkers of the response to tDCS stimulation. A larger dataset is being gathered for further analysis.

Abstract
In the last few decades, the vast majority of world states have faced increased energy consumption using more environmentally friendly production technologies. The use of traditional renewable energies like hydro, wind and solar has been the solution found. Despite this, new technical solutions and strategies are beginning to emerge, of which Floating Solar Photovoltaic (FSPV) systems are part. In this framework, southern European countries have excellent climate conditions for reinforcing the use of solar energy. This research assess the existing Portuguese potential for floating PV systems and its integration in the power grid. A floating solar power plant of 1MW in Gouvães dam included in the Tâmega hydroelectric complex, under construction in northern Portugal was sizing and evaluated its energy potential. A techno-economic feasibility study was also carried out taking into account the current investment costs and energy tariffs in the Iberian liberalized market. This integrated analysis allowed to obtain important results on the current state of the art, types of technologies available, their costs and the payback period for this type of projects.