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This paper presents a high-fidelity electro-thermal model of a half-bridge that consists of IGBTs and anti-parallel diodes. The model calculates and estimates the half-bridge voltages, currents, switching and conduction losses considering the operating temperature and current conditions. Moreover, this model is suitable for varying switching frequency operation. The electro-thermal model can be used as an evaluation tool to analyze the performance of control strategies for traction inverter from efficiency, temperature and component stress point of view. In this paper performance of Direct Torque Model Predictive Control (DTMPC) of an Interior Permanent Magnet Synchronous Motor (IPMSM) is evaluated in comparison with Indirect Field Oriented Control (IFOC) with sinusoidal pulse width modulation (PWM). The inverter model and the MPC are both implemented in C-Mex for rapid execution. The MPC algorithm implemented in this research tracks torque reference while using Maximum-Torque-Per-Ampere (MTPA) strategy and minimizing switching losses. Both control systems are able to follow the speed reference. The MPC shows a decrease in losses compared to IFOC when tested with low-speed and high-speed parts of the WLTC profile.

Water scarcity is a global problem that particularly affects islands located in arid regions or regions with limited water resources. This issue has prompted the development of non-conventional water sources such as fossil fuel-powered desalination systems. Concern about the high energy and environmental costs associated with this type of facility has created the ideal framework for the proliferation of desalination projects powered by renewable energies, especially wind energy due to the multiple advantages it offers. This article provides a bibliometric analysis to identify the advances made in wind-powered desalination on islands. While many studies explore wind-powered desalination, none compile references specific to islands. This paper analyses islands’ desalination needs and showcases wind-powered systems, exploring their types and uses. Firstly, the most relevant international scientific journals are identified to allow the subsequent selection and quantitative and qualitative analysis of articles directly dealing with wind-powered desalination systems. A total of 2344 articles obtained from the Scopus database were analyzed, of which 144 including 181 case studies were selected. Among the results of this study, an increasing year-on-year trend is observed in the number of published studies tackling wind-powered desalination. Finally, this paper presents a series of maps showing the most relevant facilities, projects, and data in this field, and provides an overview of the lessons learned in the decarbonization of desalination.

[ES] El desarrollo de los trazados ferroviarios siempre ha sido un reto para la ciudad de Valencia. En la actualidad, 2024, se presenta un gran problema a resolver, ya que las vías dividen en dos la zona sur de la ciudad. Tras analizar las diversas propuestas vigentes, se llega a la conclusión de que todavía hay puntos a resolver. Por esto, el presente trabajo prepone una alternativa que pretende resolver los problemas que la infraestructura ferroviaria genera en la ciudad mediante una estación intermodal que alberga los servicios de metro, cercanías, alta velocidad y bus. [EN] The development of railway routes has always been a challenge for the city of Valencia. Currently, in 2024, a significant issue needs to be addressed, as the tracks divide the southern part of the city in two. After analyzing the various existing proposals, it has been concluded that there are still unresolved points. Therefore, this paper proposes an alternative solution that aims to address the problems caused by the railway infrastructure in the city through an intermodal station that will accommodate metro, commuter rail, high-speed rail, and bus services.

This study aims to estimate the severity of conflicts that may arise from the introduction of connected and automated vehicles (CAVs) by examining the vehicle paths generated by microsimulations of mixed fleets of human-driven vehicles and CAVs with different levels of automation (L1-L4 vehicles). The study assesses the severity of conflicts using a holistic approach that considers three dimensions: (1) proximity to collision, via the time-to-collision (TTC) indicator; (2) potential consequences of a conflict, via single surrogate safety measures such as maximum speed (MaxS) and vehicle speed difference (DeltaS); and (3) a combination of both dimensions to assign severity scores, via TTC and velocity vectors. The study’s findings suggest that moderate penetration rates of L3 and L4 vehicles (35–55%) show significant differences in the number of traffic conflicts with varying TTC values. Additionally, high penetration rates of L3 and L4 vehicles (above 55%) result in lower values of conflict consequences measures such as MaxS and DeltaS. Furthermore, the study shows that conflict consequences decrease if the follower is a L3 or L4 vehicle. The study’s findings also reveal that there is a considerable reduction in high severity conflicts when the penetration rate of CAV levels reaches 50%, and the full operation of L4 vehicles results in a 75.5% reduction in high severity conflicts. Therefore, this study provides valuable insight into the potential severe conflicts during the transition period from manual vehicle operation to full CAV operation. Overall, the study’s findings highlight the importance of assessing the severity of potential conflicts arising from the introduction of CAVs. By considering the proximity to collision and the potential consequences of conflicts, the study provides a comprehensive assessment of the severity of conflicts. This information can inform the development of policies and strategies to ensure the safe and responsible introduction of CAVs into our transportation systems.

The Validation and Evaluation sub-project of the eCoMove project groups a number of complementary activities including the core tasks to validate the functionality of the eCoMove system and applications, and to evaluate if the aimed reduction of 20% overall energy consumption can be achieved. Besides technical requirements a validation process also has to consider non-technical requirements of potential users of the eCoMove system which were in the focus of research for this deliverable.

Our study examined the financial situation of small and medium-sized enterprises (SMEs) in the health industry of the Visegrad Four (V4: Czech Republic, Poland, Slovakia, Hungary) in the period 2008–2021. The basis of the analysis was the reports available in the Crefoport database. During the analysis, we took into account four key financial indicators (liquidity, profitability (ROA), efficiency, capital structure) and used the Kaplan–Meier survival estimator to examine the viability of enterprises. In our study, we draw attention to the national economic importance of healthcare SMEs in the CEE region, and within that, in the V4 countries during the period of Industry 4.0 and the COVID-19 pandemic. Our research goal is to examine the life expectancy of healthcare enterprises operating in Hungary at the time of their establishment, in relation to the SMEs of the other three countries. The health industry SMEs of the V4 countries showed positive growth (+18%) in the period under review compared to the average of the 3 years before the COVID-19 pandemic, in the average of the first 3 years of the COVID-19 pandemic. The study paid particular attention to the life expectancy of businesses at the time of establishment. According to our results, the life expectancy of healthcare enterprises operating in Hungary at the time of establishment is high, but it does not differ significantly from that of the other examined countries. Our study highlights that the health industry SMEs of the examined countries do not need financial support; they are standing on a stable footing, which provides them with an excellent opportunity to either expand abroad or introduce innovations.

Abstract. Marine N2 fixing microorganisms, termed diazotrophs, are a key functional group in marine pelagic ecosystems. The biological fixation of dinitrogen (N2) to bioavailable nitrogen provides an important new source of nitrogen for pelagic marine ecosystems and influences primary productivity and organic matter export to the deep ocean. As one of a series of efforts to collect biomass and rates specific to different phytoplankton functional groups, we have constructed a database on diazotrophic organisms in the global pelagic upper ocean by compiling about 12 000 direct field measurements of cyanobacterial diazotroph abundances (based on microscopic cell counts or qPCR assays targeting the nifH genes) and N2 fixation rates. Biomass conversion factors are estimated based on cell sizes to convert abundance data to diazotrophic biomass. The database is limited spatially, lacking large regions of the ocean especially in the Indian Ocean. The data are approximately log-normal distributed, and large variances exist in most sub-databases with non-zero values differing 5 to 8 orders of magnitude. Lower mean N2 fixation rate was found in the North Atlantic Ocean than the Pacific Ocean. Reporting the geometric mean and the range of one geometric standard error below and above the geometric mean, the pelagic N2 fixation rate in the global ocean is estimated to be 62 (53–73) Tg N yr−1 and the pelagic diazotrophic biomass in the global ocean is estimated to be 4.7 (2.3–9.6) Tg C from cell counts and to 89 (40–200) Tg C from nifH-based abundances. Uncertainties related to biomass conversion factors can change the estimate of geometric mean pelagic diazotrophic biomass in the global ocean by about ±70%. This evolving database can be used to study spatial and temporal distributions and variations of marine N2 fixation, to validate geochemical estimates and to parameterize and validate biogeochemical models. The database is stored in PANGAEA (http://doi.pangaea.de/10.1594/PANGAEA.774851).