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Abstract This article presents the design and experimental validation of a novel semiconductor area optimised 3300 V half bridge with Silicon Carbide (SiC) MOSFETs for HVDC converters. Based on a loss simulation, the problem statement is provided. On this results, a mathematical derivation for the optimised semiconductor area design is executed. After this step, a system loss simulation shows the performance in efficiency and specific output power. Finally, a proof of concept was provided by a scaled hardware test setup to characterise the dynamic behaviour of the novel SiC half bridge design compared to the conventional SiC half bridge.

Abstract Background Identification of mosquitoes greatly relies on morphological specification. Since some species cannot be distinguished reliably by morphological methods, it is important to incorporate molecular techniques into the diagnostic pipeline. DNA barcoding using Sanger sequencing is currently widely used for identification of mosquito species. However, this method does not allow detection of multiple species in one sample, which would be important when analysing mosquito eggs. Detection of container breeding Aedes is typically performed by collecting eggs using ovitraps. These traps consist of a black container filled with water and a wooden spatula inserted for oviposition support. Aedes mosquitoes of different species might lay single or multiple eggs on the spatula. In contrast to Sanger sequencing of specific polymerase chain reaction (PCR) products, multiplex PCR protocols targeting specific species of interest can be of advantage for detection of multiple species in the same sample. Methods For this purpose, we adapted a previously published PCR protocol for simultaneous detection of four different Aedes species that are relevant for Austrian monitoring programmes, as they can be found in ovitraps: Aedes albopictus, Aedes japonicus, Aedes koreicus, and Aedes geniculatus. For evaluation of the multiplex PCR protocol, we analysed 2271 ovitrap mosquito samples from the years 2021 and 2022, which were collected within the scope of an Austrian nationwide monitoring programme. We compared the results of the multiplex PCR to the results of DNA barcoding. Results Of 2271 samples, the multiplex PCR could identify 1990 samples, while species determination using DNA barcoding of the mitochondrial cytochrome c oxidase subunit I gene was possible in 1722 samples. The multiplex PCR showed a mixture of different species in 47 samples, which could not be detected with DNA barcoding. Conclusions In conclusion, identification of Aedes species in ovitrap samples was more successful when using the multiplex PCR protocol as opposed to the DNA barcoding protocol. Additionally, the multiplex PCR allowed us to detect multiple species in the same sample, while those species might have been missed when using DNA barcoding with Sanger sequencing alone. Therefore, we propose that the multiplex PCR protocol is highly suitable and of great advantage when analysing mosquito eggs from ovitraps. Graphical Abstract

Efficiency and power density of electric vehicle drive systems are important metrics for their performance evaluation. To address these aspects, Optimized Pulse Patterns (OPPs) can be integrated into the modulation strategy. This research investigates the effects of OPPs on the current distortion of salient permanent magnet synchronous motors (PMSMs) applying different symmetry conditions. It places a particular emphasis on three-pulse switching within the overmodulation region. A mathematical model of salient PMSMs is used to demonstrate that the voltage phase angle significantly influences current harmonics. It is revealed that even with a low number of pulses, satisfactory sinusoidal currents can be achieved at high voltage phase angles, thereby reducing the inverter's switching efforts while preserving current waveform quality. Different waveforms such as quarter- and half-wave symmetry (QWS), unrestricted half-wave symmetry (HWS) and restricted HWS are compared, with an innovative approach proposed for unrestricted HWS. The benefits and drawbacks of these waveforms in application to salient PMSMs are investigated, with emphasis on the overmodulation region. It is noted that HWS shows benefits over QWS at medium-load operating points and when zero-vectors are in the waveforms. In contrast, no significant advantages of HWS over QWS could be identified in the overmodulation region. The research proposes a practical OPP implementation strategy that balances effort and efficiency based on this knowledge. Unlike previous studies that used random initial angles to explore solutions, this study methodically examines the solution space for HWS and QWS, selecting initial angles that enhance the chances of finding the global optimum.

Neutral point clamped inverters, such as NPC, ANPC, or T-Type inverters, have emerged as competitive solutions for specific automotive traction applications due to the increase in DC-link voltage levels up to $800 \,\mathrm{V}$. Besides improved harmonic performance, certain 3-level inverter structures can provide a reconfigured failure mode operation in case of a semiconductor failure by applying a permanent neutral point connection in the faulty phase leg. This feature is a vital factor in the design of traction inverters, particularly in the context of fault-tolerant autonomous vehicles. During failure mode operation, none of the neutral point balancing techniques found in current literature are practical. Addressing this issue is crucial since the neutral point stress is high in this mode of operation. Therefore, this paper investigates the impact of stationary and dynamic neutral point voltage deviations on the motor flux in electric machines and offers a compensatory strategy for these errors. Furthermore, a new neutral point control method is presented that balances stationary neutral point voltage deviations by using a phase angle dependent voltage shift in the $\alpha / \beta$-plane. All proposed strategies are first discussed theoretically and then verified by simulation and measurements on an $800 \,\mathrm{V}$ IPMSM machine test bench.

This paper will evaluate the surge current robustness of different devices in relation to the active short circuit (ASC). For the purposes of this study, a Si IGBT and its diode, two SiC MOSFETs with different voltage ratings, a SiC JFET, and three GaN HEMTs will be compared. For the GaN devices, a eMode, a dMode, and a cascode device are employed. With the exception of the Si diode, all devices exhibited a current saturation effect. This saturation will result in significant losses and, ultimately, a thermal defect. For all devices, a safe operating area (SOA) criterion is established. For the SiC and GaN devices, the saturation voltage can be employed to define the safe operating area (SOA) criterion. In this context, two on-state resistance models will be defined for these devices. One is solely temperature-dependent, while the other also considers current saturation. Consequently, the saturation voltage and the on-resistance model represent a straightforward methodology for evaluating the ASC robustness of the devices. For all devices, a recommendation for a loss model and SOA criterion will be provided. Finally, the surge current robustness of all devices is compared. The Si, SiC and GaN devices exhibit comparable high surge current robustness in the application, with the exception of the GaN eMode, which is susceptible to strong current saturation.

Predstavljeno je istraživanje koje je provodeno u okviru znanstvenog-razvojnog projekta UNIRI INOVA „Inovativni priključak za spajanje konstrukcijskih elemenata od tankostijenih čeličnih C-profila“. Cilj projekta je pružiti bolje razumijevanje o ponašanju komponenti inovativnog priključka za spajanje elemenata od tankostijenih čeličnih C-profila.

This paper presents research results on the junction temperature measurement via the internal gate resistance in converter operation for IGBTs and its applicability to other types of active power semiconductors. A junction temperature monitor has been developed to determine the value of the temperature-dependent internal gate resistance by using a sinusoidal voltage superimposed on the gate voltage at the resonance frequency. The device enables a simple and robust junction temperature measurement in inverter operation, which is in excellent agreement with an infrared reference measurement. The method's applicability to semiconductors other than Si-IGBTs, such as SiC-MOSFETs, JFETs, and GaN devices, is verified by gate impedance measurements using a network analyzer. The gate impedance's quality factor is decisive. Other temperature-sensitive electrical parameters (TSEPs) related to the switching behavior depend on the internal gate resistance. Therefore, the findings presented are relevant for many junction temperature measurement methods.

Abstract Understanding the factors and processes that shape intra-specific sensitivity to heat stress is fundamental to better predicting the vulnerability of benthic species to climate change. Here, we investigate the response of a habitat-forming Mediterranean octocoral, the red gorgonian Paramuricea clavata (Risso, 1826) to thermal stress at multiple biological and geographical scales. Samples from eleven P. clavata populations inhabiting four localities separated by hundreds to more than 1500 km of coast and with contrasting thermal histories were exposed to a critical temperature threshold (25 °C) in a common garden experiment in aquaria. Ten of the 11 populations lacked thermotolerance to the experimental conditions provided (25 days at 25 °C), with 100% or almost 100% colony mortality by the end of the experiment. Furthermore, we found no significant association between local average thermal regimes nor recent thermal history (i.e., local water temperatures in the 3 months prior to the experiment) and population thermotolerance. Overall, our results suggest that local adaptation and/or acclimation to warmer conditions have a limited role in the response of P. clavata to thermal stress. The study also confirms the sensitivity of this species to warm temperatures across its distributional range and questions its adaptive capacity under ocean warming conditions. However, important inter-individual variation in thermotolerance was found within populations, particularly those exposed to the most severe prior marine heatwaves. These observations suggest that P. clavata could harbor adaptive potential to future warming acting on standing genetic variation (i.e., divergent selection) and/or environmentally-induced phenotypic variation (i.e., intra- and/or intergenerational plasticity).

The Gray’s sea fan, Paramuricea grayi (Johnson, 1861), typically inhabits deep littoral and circalittoral habitats of the eastern temperate and tropical Atlantic Ocean. Along the Iberian Peninsula, where P. grayi is a dominant constituent of circalittoral coral gardens, two segregating lineages (yellow and purple morphotypes) were recently identified using single-copy nuclear orthologues. The mitochondrial genomes of 9 P. grayi individuals covering both color morphotypes were assembled from RNA-seq data, using samples collected at three sites in southern (Sagres and Tavira) and western (Cape Espichel) Portugal. The complete circular mitogenome is 18,668 bp in length, has an A + T-rich base composition (62.5%) and contains the 17 genes typically found in Octocorallia: 14 protein-coding genes (atp6, atp8, cob, cox1-3, mt-mutS, nad1-6, and nad4L), the small and large subunit rRNAs (rns and rnl), and one transfer RNA (trnM). The mitogenomes were nearly identical for all specimens, though we identified a noteworthy polymorphism (two SNPs 9 bp apart) in the mt-mutS of one purple individual that is shared with the sister species P. clavata. The mitogenomes of the two species have a pairwise sequence identity of 99.0%, with nad6 and mt-mutS having the highest rates of non-synonymous substitutions.

This paper will evaluate the surge current robustness of different devices in relation to the active short circuit (ASC). For the purposes of this study, a Si IGBT and its diode, two SiC MOSFETs with different voltage ratings, a SiC JFET, and three GaN HEMTs will be compared. For the GaN devices, a eMode, a dMode, and a cascode device are employed. With the exception of the Si diode, all devices exhibited a current saturation effect. This saturation will result in significant losses and, ultimately, a thermal defect. For all devices, a safe operating area (SOA) criterion is established. For the SiC and GaN devices, the saturation voltage can be employed to define the safe operating area (SOA) criterion. In this context, two on-state resistance models will be defined for these devices. One is solely temperature-dependent, while the other also considers current saturation. Consequently, the saturation voltage and the on-resistance model represent a straightforward methodology for evaluating the ASC robustness of the devices. For all devices, a recommendation for a loss model and SOA criterion will be provided. Finally, the surge current robustness of all devices is compared. The Si, SiC and GaN devices exhibit comparable high surge current robustness in the application, with the exception of the GaN eMode, which is susceptible to strong current saturation. [ABSTRACT FROM AUTHOR]

Abstract With increasing switching speed of new power semiconductors like the SiC MOSFET, special attention has to be paid on the electromagnetic interference and its limitations. In this work, an evaluation criterion is developed as an optimisation tool for maximum exploitation of conducted electromagnetic interference limit by optimizing the switching process of a SiC MOSFET. The switching losses of power semiconductors can be reduced by increasing their switching speed. Unfortunately, at the same time, the electromagnetic interference will increase due to higher voltage and current slopes and higher switching oscillations. The electromagnetic interference caused by the switching process can be reduced by decreasing the switching speed. This also reduces the switching oscillation but inevitably increases the switching losses. The electromagnetic interference criterion developed in this paper will help to identify the proper switching speed for minimum losses under compliance with switching process related electromagnetic interference. It can be used to evaluate the benefit of more advanced gate control methods that allow increasing the switching speed without increasing the switching oscillation amplitude. The proposed method will not replace the final electromagnetic interference testing, but it will help determine the proper gate control method for lowest possible switching losses without violating the electromagnetic interference restrictions in an early development state. Measurements show that the switching losses can be reduced by 75% with a proper gate control method, where the proposed method assures the compliance with the electromagnetic interference limit.

U radu je predstavljeno istraživanje u okviru znanstvenog projekta ZIP UNIRI „Istraživanje ponašanja komponenti kompozitnog panela s integriranom čeličnom jezgrom“. Cilj znanstvenog projekta je pružiti bolje razumijevanje o ponašanju komponenti inovativnog konstruktivnog panelnog sustava kako bi se istražio potencijal njegove primjene u građevinarstvu.

This study presents an innovative design for a cold-formed steel polyurethane (CFS-PU) composite wall panel, combining a cold-formed steel frame, a polyurethane foam infill, and a gypsum fibreboard sheathing. The foam filling process, in which the foam is injected under pressure, ensures uniform distribution, bonding, and interaction of all panel components. The aim of the study is to evaluate the behaviour of the CFS-PU composite panels and the influence of the PU foam and sheathing on the performance of the CFS frame structure. For this purpose, a comprehensive test programme was conducted with nine full-scale specimens, including four CFS-F specimens without infill and sheathing and five CFS-PU specimens with infill and sheathing on both sides. The study examined various aspects of the specimens, including failure modes, stability, stiffness, load-bearing capacity, and ductility index. By analysing these parameters, valuable insights were gained into the performance characteristics of the composite wall panels. The load-bearing capacity of the CFS-PU test specimens was improved by 2.34 times and the stiffness by 1.47 times compared to the CFS-F test specimens. The positive results highlight the potential of foam and sheathing in improving the axial compression performance of CFS walls.

This paper presents an experimental and numerical investigation of the tensile and compressive behaviour of a novel U-connector in the cold-formed steel (CFS) truss-to-column connection. Tensile tests were performed on 12 specimens representing the tension chords of the trusses in the connection. The results were used to validate a finite element model. The validated model was then subjected to both compressive and tensile loads, which revealed low stiffness in both the compressive and tensile components of the proposed connection. An optimisation of the geometry by using one long nut instead of two nuts was carried out to improve the behaviour and stiffness of the connection. The optimised results were compared with both experimental and numerical data, and conclusions were drawn regarding the effectiveness of the components in the proposed connection. The use of long-nut optimisation in the tension and compression components of the proposed connection shows a significant increase in load-bearing capacity, which makes it very promising for future applications in CFS truss-to-column connections. However, further validation through experimental testing is required to confirm the effectiveness and reliability of the connection in full-scale structures.

Human and animal vector-borne diseases, particularly mosquito-borne diseases, are emerging or re-emerging worldwide. Six Aedes invasive mosquito (AIM) species were introduced to Europe since the 1970s: Aedes aegypti, Ae. albopictus, Ae. japonicus, Ae. koreicus, Ae. atropalpus and Ae. triseriatus. Here, we report the results of AIMSurv2020, the first pan-European surveillance effort for AIMs. Implemented by 42 volunteer teams from 24 countries. And presented in the form of a dataset named “AIMSurv Aedes Invasive Mosquito species harmonized surveillance in Europe. AIM-COST Action. Project ID: CA17108”. AIMSurv2020 harmonizes field surveillance methodologies for sampling different AIMs life stages, frequency and minimum length of sampling period, and data reporting. Data include minimum requirements for sample types and recommended requirements for those teams with more resources. Data are published as a Darwin Core archive in the Global Biodiversity Information Facility- Spain, comprising a core file with 19,130 records (EventID) and an occurrences file with 19,743 records (OccurrenceID). AIM species recorded in AIMSurv2020 were Ae. albopictus, Ae. japonicus and Ae. koreicus, as well as native mosquito species.

Mosquitoes of the genus Culex are important vectors of a variety of arthropod-borne viral infections. In most of the northern parts of the USA, Cx. pipiens/restuans is the predominant representative of this genus. As vectors, they play a key role in the spreading of arboviruses and thus, knowledge of the population dynamic of mosquitoes is important to understand the disease ecology of these viruses. As poikilotherm animals, the vital rates of mosquitoes are highly dependent on ambient temperature, and also on precipitation. We present a compartmental model for the population dynamics of Cx. pipiens/restuans. The model is driven by temperature, precipitation, and daytime length (which can be calculated from the geographic latitude). For model evaluation, we used long-term mosquito capture data, which were averaged from multiple sites in Cook County, Illinois. The model fitted the observation data and was able to reproduce between-year differences in the abundance of the Cx. pipiens/restuans mosquitoes, as well as the different seasonal trends. Using this model, we evaluated the effectiveness of targeting different vital rates for mosquito control strategies. The final model is able to reproduce the weekly mean Cx. pipiens/restuans abundance for Cook County with a high accuracy, and over a long time period of 20 years.

In the last few years, the endemic Mediterranean bivalve Pinna nobilis has been exposed to dramatic mortality in its entire area, which could lead to the extinction of the species. Throughout the Mediterranean, a lot of effort is being put into finding ways of preserving it. One of the methods used to monitor recruitment and juveniles’ survival is the installation of collectors for bivalve larvae. We installed collectors at two locations: in Brijuni National Park (North Adriatic) and Luka Cove (central Adriatic). Our aim was to compare the fouling community on the collectors in two consecutive years (2019 and 2020), especially because the installation of collectors in 2020 coincided with mass mortality events of P. nobilis in the area. The number and size of juvenile P. nobilis and the qualitative and quantitative composition of the fouling communities were determined. The results show a reduction in the number and size of juvenile P. nobilis and an explosion of the invasive bivalve Anadara transversa population on collectors in the second year. In Luka Cove, another invasive species—the ascidian Styela plicata—also seriously affected other organisms on the collectors to the point of preventing analysis of the fouling community.

This article presents the design and experimental validation of a novel semiconductor area optimised 3300 V half bridge with Silicon Carbide (SiC) MOSFETs for HVDC converters. Based on a loss simulation, the problem statement is provided. On this results, a mathematical derivation for the optimised semiconductor area design is executed. After this step, a system loss simulation shows the performance in efficiency and specific output power. Finally, a proof of concept was provided by a scaled hardware test setup to characterise the dynamic behaviour of the novel SiC half bridge design compared to the conventional SiC half bridge. [ABSTRACT FROM AUTHOR]

The aim was to study functional abilities and to create functional classification of children with cerebral palsy (CP) in Krapina-Zagorje County, based on the classification of gross and fine motor skills and associated impairments. Classification was performed according to the SCPE (Surveillance of Cerebral Palsy in Europe) criteria. We used standardized and complementary functional classification systems for cerebral palsy to create a functional profile. Research included 44 children with CP in the age range of 4 to 18 years. The results showed that the majority of children had bilateral spastic CP (63.6%), followed by unilateral spastic (22.7%) while the representation of dyskinetic CP was 9.09% and ataxic CP 4.55%. Based on the classification of gross and fine motor skills, 43.2% of children had the ability to walk, 11% of children could walk with assistive mobility devices, while 45.4% of children had a low functional level. The study also analyzed the associated impairments where higher classification score of motor impairment correlated with the severity of impairment. The results showed that children with dyskinetic CP and severe motor impairment could have mild cognitive impairment. We systematically present the neuropsychological and functional profile according to the CP type.

A rare case of thoracolumbar spondyloptosis after a severe polytraumatic event is presented. Spondyloptosis accounts for a minor proportion of all spine trauma cases and is usually accompanied by complete neurological deficit. A 48-year-old man suffered severe polytrauma after having been hit by a truck at the work place. Radiographic scanning revealed multiple traumatic injuries and spondyloptosis at the L1/L2 level in coronal plane. However, despite extensive injuries, ASIA score was estimated as D. The patient underwent urgent multidisciplinary surgery due to severe head injuries. The next surgery was performed to stabilize the thoracolumbar segment and to preserve neurological functions. The surgery included implantation of transpedicular titanium screws via posterior approach. Good postoperative recovery was achieved during early postoperative rehabilitation at our Department, which was estimated as ASIA score D. In conclusion, prompt operative treatment to achieve neural integrity and early rehabilitation should be considered as the gold standard in such complicated injuries. Postoperative recovery largely depends on the quality of rehabilitation, which leads to improvement of patient self-care and normal social and psychological functions. In our case, the good preoperative neurological status of the patient also contributed to better postoperative outcome.

In this study, an innovative fabricated angle bracket connection for joining cold-formed steel structures is presented and investigated. The innovation lies in the especially designed and manufactured angle bracket and in the method of connecting the angle bracket for the C-profile using clinch pressing. This novel angle bracket can be used to connect cold-formed steel elements such as beam trusses at the ends of the chords or for anchoring the column base. Five specimens were fabricated and experimentally tested under monotonic tensile loading until failure. A specific tool was developed to properly hold C-profiles. Three displacement measurement procedures were performed, and the appropriate method was used to analyse the test results. The main failure mechanism of the angle bracket connection determined by the tests was pull-through of the M12 bolt, whose resistance is compared with the calculated values according to the AISI S100-16 and EN 1993-1-3 standards. There was no bearing failure in the innovative connection between the C-profile and the angle bracket, which indicates an increase in the bearing capacity of the connection.

In Austria, only fragmented information on the occurrence of alien and potentially invasive mosquito species exists. The aim of this study is a nationwide overview on the situation of those mosquitoes in Austria. Using a nationwide uniform protocol for the first time, mosquito eggs were sampled with ovitraps at 45 locations in Austria at weekly intervals from May to October 2020. The sampled eggs were counted and the species were identified by genetic analysis. The Asian tiger mosquito Aedes albopictus was found at two sites, once in Tyrol, where this species has been reported before, and for the first time in the province of Lower Austria, at a motorway rest stop. The Asian bush mosquito Aedes japonicus was widespread in Austria. It was found in all provinces and was the most abundant species in the ovitraps by far. Aedes japonicus was more abundant in the South than in the North and more eggs were found in habitats with artificial surfaces than in (semi-) natural areas. Further, the number of Ae. japonicus eggs increased with higher ambient temperature and decreased with higher wind speed. The results of this study will contribute to a better estimation of the risk of mosquito-borne disease in Austria and will be a useful baseline for a future documentation of changes in the distribution of those species.

A devastating mass mortality event (MME) very likely caused by the protozoan Haplosporidium pinnae first detected in 2016 in the Western Mediterranean Sea, is pushing the endemic bivalve Pinna nobilis to near extinction. Populations recovery, if possible, will rely on larval dispersal from unaffected sites and potential recolonization through recruitment of resistant juveniles. To assess the impact of the MME on the species’ larval recruitment, an unprecedented network of larval collector stations was implemented over several thousands of kilometers along the Western Mediterranean coasts during the 3 years after the onset of the MME. The findings of this network showed a generalized disruption in recruitment with dramatic consequences for the recovery of the species. However, there were exceptions to this pattern and recruits were recorded in a few sites where the resident population had been decimated. This hints to the importance of unaffected populations as larval exporting sources and the role of oceanographic currents in larval transport in the area, representing a beacon of hope in the current extremely worrying scenario for this emblematic species.