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Numerous studies have identified traveling waves in the cortex and suggested they play important roles in brain processing. These waves are most often measured using macroscopic methods that are unable to assess the local spiking activity underlying wave dynamics. Here, we investigated the possibility that waves may not be traveling at the single neuron scale. We first show that sequentially activating two discrete brain areas can appear as traveling waves in EEG simulations. We next reproduce these results using an analytical model of two sequentially activated regions. Using this model, we were able to generate wave-like activity with variable directions, velocities, and spatial patterns, and to map the discriminability limits between traveling waves and modular sequential activations. Finally, we investigated the link between field potentials and single neuron excitability using large-scale measurements from turtle cortex ex vivo. We found that while field potentials exhibit wave-like dynamics, the underlying spiking activity was better described by consecutively activated spatially adjacent groups of neurons. Taken together, this study suggests caution when interpreting phase delay measurements as continuously propagating wavefronts in two different spatial scales. A careful distinction between modular and wave excitability profiles across scales will be critical for understanding the nature of cortical computations.

Freight transport accounts for about half of all distances travelled in Europe. Therefore, freight transport is one of the decisive factors for reducing greenhouse gases and air pollutants. For this reason, the electrification of road freight transport is being promoted as part of the project "BEV Goes eHighway—[BEE]". The data basis for the modelling used in this project is an electric drive axle for a heavy commercial vehicle, which was developed in the "Concept-ELV2" project. Based on the results of the previous project, the methodological tools that were developed are presented in this paper. These allow a wide range of possible powertrain topologies to be considered at the concept stage of development based on an estimation of future system characteristics. For this purpose, the components are automatically designed taking into account the mutual influence of the requirements and are evaluated in the context of the holistic system. This publication focuses on the efficiency and thermal evaluation of the transmission stages of the addressed electric drive units and validates the developed models using a pototypically designed electric commercial vehicle axle. [ABSTRACT FROM AUTHOR]

In this paper, a new configuration of Marx generator with high‐voltage (HV) gain is presented for electroporation applications. Each module consists of one switch, one capacitor, and two diodes. The capacitors are charged in parallel with the input inductor and the input DC voltage source simultaneously; eventually, the charged capacitors are connected in series, and the HV output pulses are generated. The load is connected differently at the output stage, and there is not any switch at the output stage to generate the HV pulses. The majority of Marx generators suffer from the high number of modules to reach the desired pulse peak voltage. Due to the high‐voltage gain of the proposed topology, fewer modules are needed to achieve the desired HV pulse peak voltage. Mathematical analysis is presented along with a full design of the system components. Soft switching reduces the switching power loss in this converter, which is presented in detail. A comparative study is carried out to demonstrate the advantages of the proposed structure. Finally, simulation and experimental results are presented to validate the proposed concept. [ABSTRACT FROM AUTHOR]

Battery management systems (BMSs) are widely used in different battery applications to maximize the system operating efficiency. Due to different applications of BMS, different topologies are developed and used for implementation. In this letter, we propose a modular BMS circuit for electric motorcycles battery voltage applications and present a BMS platform for testing. We conduct a real-time evaluation of the BMS in the designed BMS platform considering a varying total input load voltage ranging from 51.2–67.2 V. The real-time evaluation is conducted using four local modules and one central module. The results are verified using the BMS platform designed for this specific BMS. The BMS voltage measurement accuracy is evaluated. Actual input load voltage values are used to verify the voltage values measured by the BMS, and significantly high accuracy is achieved with a mean RMSE of 0.0018895. In terms of relative error, a mean value of 0.03575 is achieved for the four-cell modular BMS application. [ABSTRACT FROM AUTHOR]

Freight transport accounts for about half of all distances travelled in Europe. Therefore, freight transport is one of the decisive factors for reducing greenhouse gases and air pollutants. For this reason, the electrification of road freight transport is being promoted as part of the project “BEV Goes eHighway—[BEE]”. The data basis for the modelling used in this project is an electric drive axle for a heavy commercial vehicle, which was developed in the “Concept-ELV2” project. Based on the results of the previous project, the methodological tools that were developed are presented in this paper. These allow a wide range of possible powertrain topologies to be considered at the concept stage of development based on an estimation of future system characteristics. For this purpose, the components are automatically designed taking into account the mutual influence of the requirements and are evaluated in the context of the holistic system. This publication focuses on the efficiency and thermal evaluation of the transmission stages of the addressed electric drive units and validates the developed models using a pototypically designed electric commercial vehicle axle.

Numerous studies have identified traveling waves in the cortex and suggested they play important roles in brain processing. These waves are most often measured using macroscopic methods that are unable to assess the local spiking activity underlying wave dynamics. Here, we investigated the possibility that waves may not be traveling at the single neuron scale. We first show that sequentially activating two discrete brain areas can appear as traveling waves in EEG simulations. We next reproduce these results using an analytical model of two sequentially activated regions. Using this model, we were able to generate wave-like activity with variable directions, velocities, and spatial patterns, and to map the discriminability limits between traveling waves and modular sequential activations. Finally, we investigated the link between field potentials and single neuron excitability using large-scale measurements from turtle cortex ex vivo. We found that while field potentials exhibit wave-like dynamics, the underlying spiking activity was better described by consecutively activated spatially adjacent groups of neurons. Taken together, this study suggests caution when interpreting phase delay measurements as continuously propagating wavefronts in two different spatial scales. A careful distinction between modular and wave excitability profiles across scales will be critical for understanding the nature of cortical computations., Competing Interests: YO, AR, RP, YL, PB, MS No competing interests declared, (© 2023, Orsher et al.)

This paper presents the optimal design and performance analysis of a novel synchronous reluctance motor with outer rotor for determination of the effect of the rotor pole shape on the machine's performances. The investigation has been made in order to find the possible ways to improve the power factor with refining the rotor geometry without using permanent magnets. Starting from the design of the machine with classical rotor pole that was implemented in FLUX 2D, a finite element analysis software coupled with an optimal design procedure implemented in MATLAB was performed. The purpose of this complex co-simulation was to obtain several outer rotor structures that increase the performances of the machine: saliency ratio, power factor and torque density. For the proposed structures, especially for the modular topology, the obtained results of saliency and power factor have never been presented in the past literature. Hence, this represents a useful starting point for the following analysis of outer rotor synchronous reluctance machines with improved power factor. [ABSTRACT FROM AUTHOR]

In this paper, a modular topology is presented for generating high-voltage pulsed power. The proposed structure consists of Marx-type modules, which are based on the switched-capacitor (SC) concept. This module receives an input voltage and, depending on the requirement of the user, produces an output voltage either equal to the input or twice as much as the input voltage, which shows the flexibility of our model. The capability of the module to produce a doubled output makes it appropriate for applications with low input voltage sources. Also, the topology has the capability of generating combined wide and narrow pulses. The topology was simulated in MATLAB Simulink and a laboratory setup was built to test its operation. The results validate the theoretical basis of the structure. [ABSTRACT FROM AUTHOR]

This paper presents a power electronics converter to generate bipolar high-voltage pulses using low-voltage dc source. Converter is designed based on charging of different capacitors by a predetermined switching pattern and their discharging on the load for pulsed power applications. Low number of power electronics devices and bulky transformer elimination are main advantages of the proposed converter. According to new findings, bipolar high-voltage pulses may lead to higher efficiency in many applications, such as food sterilization industry. The proposed pulse generator generates bipolar controllable pulses with a modular circuit structure based on a capacitor-switched network. Experimental results are presented to verify the analysis. [ABSTRACT FROM AUTHOR]

This paper presents a novel three-phase U-core stator motor with the modular topology based on the conventional single-phase motor to solve the problems of high torque ripple and non-self-starting ability, which has the similar advanced performance as a two-phase motor. Basic topology and torque analysis are discussed for the proposed three-phase motor in terms of the single-phase modules. Finite-element method (FEM) is carried out to compare and verify the competitive performance of the proposed motor and the practicability of such modular design concept. The dynamic starting performance in the proposed three-phase motor is finally simulated by utilizing the Simulink models and compared to those of the single-phase and twophase models. [ABSTRACT FROM AUTHOR]

This study presents a design methodology based on scale models for low speed switched reluctance generators (SRG). This study is motivated by the application of SRG to direct‐drive wind turbines and other low speed renewable energy systems. In direct drive energy converters considerable simplifications result from the elimination of the gear box which has generally been used to interface a slowly rotating shaft with the generator shaft. The comparison and evaluation of magnetic structures plays an important role in the SRG design. General design methodologies are usually oriented towards the evaluation of stator/rotor poles combinations for regular switched reluctance machines. Besides covering that feature, the formulation of scale laws proposed is also suitable to compare other SRG topologies distinguished by different characteristics of electric and magnetic circuits and their own relative position. In addition, this methodology can be extended to other physical phenomena such as thermal changes and magnetic saturation by introducing some constraints. The running example compares a modular short flux‐path topology versus a low speed 20 kW prototype SRG designed for a direct drive wind turbine. The modular topology can optimise the efficiency and weight taking benefits from the significant gain of power per unit of volume and lower losses. [ABSTRACT FROM AUTHOR]

A 10 kJ electromagnetic forming (EMF) modulator with energy recovery based on two resonant power modules, each containing a 4.5 kV/30-kA silicon controlled rectifier, a 1.11-mF capacitor bank and an energy recovery circuit, working in parallel to allow a maximum actuator discharge current amplitude and rate of 50 kA and 2 kA/ \(\mu \) s was successfully developed and tested. It can be plugged in standard single phase 230 V/16 A mains socket and the circuit is able to recover up to 32% of its initial energy, reducing the charging time of conventional EMF systems by up to 68%. [ABSTRACT FROM PUBLISHER]

We consider a strongly nonlinear monotone elliptic problem in generalized Orlicz-Musielak spaces. We assume neither a Δ nor ∇-condition for an inhomogeneous and anisotropic N-function but assume it to be log-Hölder continuous with respect to x. We show the existence of weak solutions to the zero Dirichlet boundary value problem. Within the proof the L-truncation method is coupled with a special version of the Minty-Browder trick for non-reflexive and non-separable Banach spaces. [ABSTRACT FROM AUTHOR]