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Isolated bidirectional DC–DC converters are becoming increasingly important in various applications, particularly in the electric vehicle sector, due to their ability to achieve bidirectional power flow and their safety features. This paper aims to review the switch strategies and topologies of isolated bidirectional DC–DC converters, with a specific focus on their applications in the field of electric vehicles. From the perspective of topology, PWM-type isolated bidirectional DC–DC converters, dual active bridge converters, and resonant-type isolated bidirectional DC–DC converters constitute the three main categories of these converters. The paper further examines the traditional switch strategies of these converters and discusses how specific switch technologies, such as single-phase shift, expanding-phase shift, double-phase shift, and triple-phase shift, can enhance the overall performance of isolated bidirectional DC–DC converters. The paper meticulously examines the characteristics of each topology and control scheme, as well as their typical use cases in practical applications. Particularly, the paper delves into the applications of isolated bidirectional DC–DC converters in the electric vehicle sector and draws conclusions regarding their potential and trends in future electric vehicle technology. [ABSTRACT FROM AUTHOR]

The electrification of road transport is developing dynamically around the world. Many automotive companies are introducing electric vehicles to the market, and their popularity is constantly growing. The increasing popularity of electric vehicles is caused by individual countries' governments encouraging people to switch to electric vehicles and their lower operating costs. In 2022, the number of electric vehicles in China will exceed 10 million. Europe and the USA rank second and third in global electric car stock, respectively. The number of available electric vehicle models is constantly growing, remaining approximately 2.5 times smaller than the case of vehicles with an internal combustion engine. Among others, a significant limitation to the popularity of electric cars is users' fear of range and the density of the charging infrastructure network. This paper presents the objectives regarding public areas and charging stations around the European Union's comprehensive and core transport network. It is worth noting that the vehicle and charging point's charging connectors vary depending on the geographical region. Therefore, the currently used charging connectors for different regions are presented. Charging time depends significantly on the charging current, the power of the charging point, and the devices installed in the vehicle. The paper analyzes the limitations of charging power resulting from the onboard charger's power and the charging point's power. It presents the charging time of selected electric vehicles. The second aspect that is also the subject of user concerns and discussed in this article is issues related to the safety of electric vehicles. General safety indicators of such vehicles based on Euro-NCAP tests are characterized. Attention was also paid to more detailed problems related to active and passive safety and functional safety analyses. The issue of the fire hazard of electric vehicles was discussed together with modern experiences regarding post-accident procedures in the event of fires. [ABSTRACT FROM AUTHOR]

This article presents a computer vision-based approach to switching electric locomotive power supplies as the vehicle approaches a railway neutral section. Neutral sections are defined as a phase break in which the objective is to separate two single-phase traction supplies on an overhead railway supply line. This separation prevents flashovers due to high voltages caused by the locomotives shorting both electrical phases. The typical system of switching traction supplies automatically employs the use of electro-mechanical relays and induction magnets. In this paper, an image classification approach is proposed to replace the conventional electro-mechanical system with two unique visual markers that represent the 'Open' and 'Close' signals to initiate the transition. When the computer vision model detects either marker, the vacuum circuit breakers inside the electrical locomotive will be triggered to their respective positions depending on the identified image. A Histogram of Oriented Gradient technique was implemented for feature extraction during the training phase and a Linear Support Vector Machine algorithm was trained for the target image classification. For the task of image segmentation, the Circular Hough Transform shape detection algorithm was employed to locate the markers in the captured images and provided cartesian plane coordinates for segmenting the Object of Interest. A signal marker classification accuracy of 94% with 75 objects per second was achieved using a Linear Support Vector Machine during the experimental testing phase. [ABSTRACT FROM AUTHOR]

This study aimed to uncover the attitudes, preferences, and perceptions of Hail residents toward electric vehicles (EVs) by employing a real-life survey-based approach. This paper presents an in-depth analysis of the potential adoption and impact of EVs to clarify the picture of the transition from using traditional vehicles to using EVs in Hail City, Saudi Arabia. Hail is rapidly becoming a more urbanized city; in the past few decades, the city's area has expanded from 3242 to 17,526 hectares, and its population has increased dramatically from 82,900 in 1984 to 344,111 in present day. As a result, the city is facing increasingly difficult challenges related to rising vehicle emissions and environmental degradation. A survey was conducted among a diverse group of 346 participants. The survey results show an average of 3.15 cars per family, which indicates a strong connection with personal vehicles. The survey provides a comprehensive picture of the respondents' socioeconomic background, indicating an average household size of 5.8 people and an average monthly income of SR 13,350. The key findings from the survey reveal that approximately 52.3% of the respondents have 3–4 family members, and nearly half of the families own one or two cars. Government employees formed a major proportion of the respondents. The results show a significant inclination toward EVs, with 78.6% of the participants being aware of EV charging stations and 37.9% expressing a positive attitude towards switching to electric vehicles. Despite this, a large majority (88.7%) have never driven an electric car. The respondents' driving habits are further explored in the survey, which reveals an average of 2.1 h of daily driving. Furthermore, the respondents disclosed an average weekly fuel expenditure of SR 235. The results also highlight that the average weekly cost for fuel varies among the respondents, with most respondents spending no more than SR 300 per week. Additionally, this study examined the daily vehicle mileage, revealing that 37.9% of the respondents have a daily mileage of 51 to 100 km, which impacts the planning of charging station capacities and locations. The findings suggest a growing interest in EVs and highlight the need for strategic infrastructure development to support the anticipated surge in EV adoption. [ABSTRACT FROM AUTHOR]

A recent paper published in the National Science Review discusses the discovery of new electro-optical properties in exfoliated vermiculite nanosheets. The researchers found that these nanosheets possess high Kerr coefficients, which are desirable for applications such as Kerr displays and terahertz modulators. The authors demonstrated the potential of vermiculite nanosheets by creating a proof-of-concept displayable pixel device with high luminance uniformity. This study highlights the importance of studying the properties of well-known materials to uncover unexpected and technologically relevant properties. [Extracted from the article]

Nonreciprocal quantum transport effect is mainly governed by the symmetry breaking of the material systems and is gaining extensive attention in condensed matter physics. Realizing electrical switching of the polarity of the nonreciprocal transport without external magnetic field is essential to the development of nonreciprocal quantum devices. However, electrical switching of superconducting nonreciprocity remains yet to be achieved. Here, we report the observation of field-free electrical switching of nonreciprocal Ising superconductivity in Fe3GeTe2/NbSe2 van der Waals (vdW) heterostructure. By taking advantage of this electrically switchable superconducting nonreciprocity, we demonstrate a proof-of-concept nonreciprocal quantum neuronal transistor, which allows for implementing the XOR logic gate and faithfully emulating biological functionality of a cortical neuron in the brain. Our work provides a promising pathway to realize field-free and electrically switchable nonreciprocity of quantum transport and demonstrate its potential in exploring neuromorphic quantum devices with both functionality and performance beyond the traditional devices. The authors demonstrate magnetic-field-free electric switching of superconducting nonreciprocity in Fe3GeTe2/NbSe2 heterostructures. They apply this to propose and demonstrate a proof-of-concept "neural transistor", a tetrode device that realizes an XOR gate with only a single transistor. [ABSTRACT FROM AUTHOR]

The topic of this review is the physical gelling of liquid crystalline (LC) phases. It allows the combination of order and mobility of the LC-phase with macroscopic stability, which makes it a soft material. Thus, the gelled LCs acquire properties of LC-elastomers without the need for complicated chemistry to allow polymerization and crosslinking. But, instead, an LC-material (either a pure compound or a mixture) can be mixed with a few percent of a gel-forming agent, which self-assembles into long fibers that span the volume of the gel and make it a soft-solid. The use of azo-containing gel-forming agents thereby allows us to make gelation not only thermo-responsive, but also photo-responsive (trans-cis isomerization). This review discusses the micro-morphology of the gelled LCs and their influence on the mechanical properties and the switching in external electric fields. In addition, the potential of reversibility is discussed, which is not only interesting for recycling purposes, but also offers a route to inscribe a complex director pattern into the gelled liquid crystal. [ABSTRACT FROM AUTHOR]

Bismuth ferrite (BiFeO3) is a multiferroic material that exhibits both ferroelectricity and canted antiferromagnetism at room temperature, making it a unique candidate in the development of electric-field controllable magnetic devices. The magnetic moments in BiFeO3 are arranged into a spin cycloid, resulting in unique magnetic properties which are tied to the ferroelectric order. Previous understanding of this coupling has relied on average, mesoscale measurements. Using nitrogen vacancy-based diamond magnetometry, we observe the magnetic spin cycloid structure of BiFeO3 in real space. This structure is magnetoelectrically coupled through symmetry to the ferroelectric polarization and this relationship is maintained through electric field switching. Through a combination of in-plane and out-of-plane electrical switching, coupled with ab initio studies, we have discovered that the epitaxy from the substrate imposes a magnetoelastic anisotropy on the spin cycloid, which establishes preferred cycloid propagation directions. The energy landscape of the cycloid is shaped by both the ferroelectric degree of freedom and strain-induced anisotropy, restricting the spin spiral propagation vector to changes to specific switching events. Previous understanding of the coupling between ferroelectric structure and magnetic texture in BiFeO3 has relied on mesoscale measurements. Here, the authors image coupling directly, showing a complex spin cycloid controlled with electric field. [ABSTRACT FROM AUTHOR]