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The collisional electron spectroscopy method for analyzing and determining gaseous impurities was further developed to realize the operation in an open environment. In addition, the method not only facilitates the registration of the impurity components, but also the reactive radicals generated from the discharge reaction. The sandwich-like discharge structure was used to generate a stable, non-local, negative glow equipotential plasma in an open environment, and the I–V characteristic curve of the plasma was collected using an additional sensor electrode. The collisional electron spectroscopy was obtained from the first derivative of the probe current I with respect to the probe potential V by adding a diffusion function to correct it. In addition, our experiment verifies the reliability of the sink theory.

The plasma sheath causes the spacecraft’s communication signal to attenuate dramatically during the re-entry period, which seriously threatens the astronauts. However, valid experimental protocols have not been obtained hitherto. To realize the propagation of electromagnetic waves in negative permittivity background of the plasma sheath, alumina columns are embedded in the plasma background to form plasma photonic crystals, which can support the coupling of evanescent waves between the alumina columns. We experimentally demonstrate the realization of communication in blackout scenario by achieving a complete passing band in the plasma cutoff region. For high frequency communications in the plasma sheath, electromagnetic wave propagation based on topological edge states is also experimentally demonstrated. Furthermore, we realize a triply-degenerate Dirac cone formed dynamically at the center of the Brillouin zone by modulating the electron density, where electromagnetic wave exhibits high transmittance and does not experience phase accumulation at the Dirac point. Our work thus not only provides an effective approach to overcome the communication blackout problem, but the design can also be served as a promising experimental platform to explore topological electromagnetic phenomena.

Artificial intelligence analysis methods for chest X-ray images are limited by insufficient annotation data and varying levels of annotation, resulting in weak generalization ability and difficulty in clinical dissemination. Here, we present EVA-X, an innovative foundational model based on X-ray images with broad applicability. EVA-X uses a self-supervised learning method capable of capturing both semantic and geometric information from unlabeled images for universal X-ray image representation. It has demonstrated exceptional performance in chest disease analysis and localization, becoming a model capable of spanning over 20 different chest pathologies and achieving leading results in over 11 different pathology detection tasks. Additionally, EVA-X significantly reduces the burden of data annotation in the medical AI field, showcasing strong potential in the domain of few-shot learning. The emergence of EVA-X will greatly propel the development and application of foundational medical models, leading to potential improvements in future medical research and clinical practice.

The transmission properties in two-dimensional plasma photonic crystal composed of plasma and yttrium–iron–garnet rods with square lattices are demonstrated under different electron densities and external magnetic fields. The TE and TM modes respond to the permittivity tensor and the permeability tensor produced by the magnetic field. For TM polarization, two distinct attenuation peaks appear in the ranges of 3.4–3.62 GHz and 3.78–4 GHz, induced by the external magnetic fields, and the location of these attenuation peaks can be modulated by modifying the electron densities. For TE polarization, a flat transmission spectrum was obtained in the range of 4–4.6 dB by increasing the electron density to 3×1012 cm−3. Then, a Y-shaped plasma photonic crystal waveguide is designed. The transmission path can be modulated by changing the direction of the external magnetic field. By regulating the electron density, switching the Y-shaped waveguide on and off can be achieved.

The Gatchina discharge phenomenon holds significant promise as a laboratory model for simulating ball lightning. However, crucial aspects concerning the plasma components of the resulting afterglow remain unresolved. Notably, the measurement of the electron density, a critical parameter, has not been fully achieved thus far. In this study, microwave diagnostics and video recording were employed during a pulsed Gatchina discharge, along with synchronous measurement of discharge current and voltage. Distinct antennas were positioned at different heights to enable separate diagnosis of the discharge and the ensuing long‐lived afterglow. The findings revealed that during the active phase of the Gatchina discharge, the plasma density was substantial enough to cause reflection of an electromagnetic wave with a frequency of 20 GHz from this highly conductive object. In the afterglow, the signal experienced only a moderate weakening of 10–20 percent, facilitating the determination of the time dependence of average electron density during the afterglow's passage between the two antennas. These measurements verified the unusually slow plasma decay in the afterglow of the Gatchina discharge, suggesting the potential significance of chemi‐ionisation processes involving long‐lived (metastable) particles.

The bridge crane, as an efficient transportation tool, isss widely used in various fields. Currently, research on bridge cranes mainly focuses on the single-pendulum domain. However, in the actual transportation process, the mass of the hook cannot be ignored, and it can cause relative oscillations of the crane, similar to a double-pendulum model. Therefore, many experts and scholars have researched double-pendulum bridge cranes. In the operation of a double-pendulum bridge crane with load hoisting/lowering, uncertainties such as frictional resistance and air resistance cannot be accurately fed back to the controller input, posing a significant challenge in designing anti-swing control strategies. In this paper, an adaptive coupled tracking anti-swing control strategy is proposed to address the above issues. Specifically, based on the principle of energy dissipation, more system parameter information is incorporated into the design of coupled trajectories. By combining the S-shaped trolley motion reference trajectory, an error-tracking trajectory for the trolley is designed. Considering the uncertainties of air resistance and frictional resistance, an adaptive rate is used to estimate the resistance coefficients online and feedback to the system input, ultimately designing an adaptive trajectory tracking coupled controller. The asymptotic stability of the equilibrium point of the closed-loop system is proven using the Lyapunov method and Barbalat lemma. Extensive experimental simulations are conducted to demonstrate the good control performance of the proposed control strategy.

Recently, plain vision transformers (ViTs) have shown impressive performance in various computer vision tasks due to their powerful modeling capabilities and large-scale pre-training. However, they have yet to show excellent results in gaze estimation tasks. In this paper, we take the advanced Vision Transformers further into the task of Gaze Estimation (TransGaze). Our framework adeptly integrates the distinctive local features of the eyes while maintaining a simple and flexible structure. It can seamlessly adapt to various large-scale pre-trained models, enhancing its versatility and applicability in different contexts. It first demonstrates the pre-trained ViTs could also show strong capabilities on gaze estimation tasks. Our approach employs the following strategies: (i) Enhancing the self-attention module among facial feature maps through straightforward token manipulation, effectively achieving complex feature fusion, a feat previously requiring more intricate methods; (ii) Leveraging the plain of TransGaze and the inherent adaptability of Plain ViT, we introduce a pre-trained model for gaze estimation. This model reduces training time by over 50 % and exhibits strong generalization performance. We evaluate our TransGaze on GazeCapture and MPIIFaceGaze datasets and achieve state-of-the-art performance with less training costs. Our models and codes will be available.

During the actual transportation process, overhead cranes are always affected by the double-pendulum effect, resulting in excessive swinging angles that affect the control performance of the anti-swing system. Moreover, the viscous resistance, air resistance, and swing angle suppression force encountered during transportation have uncertainties and cannot be accurately fed back to the controller’s input, resulting in poor swing angle suppression capability. In order to suppress the undesired swinging of the hook and load, this paper proposes an adaptive coupling anti-swing control strategy with enhanced swing angle suppression under initial input constraints. Specifically, more system parameters are included in the design of the coupling signal, and a sine term is introduced to adjust the oscillation of the hook and load swing angle. At the same time, a hyperbolic tangent term is introduced to suppress the driving force of the overhead crane to prevent excessive driving force from affecting the control performance. Furthermore, for the problem of uncertain parameters, an adaptive law is used to estimate the uncertain parameters online, ultimately designing an adaptive coupling anti-swing controller with enhanced swing angle suppression under initial input constraints. The asymptotic stability of the equilibrium point of the closed-loop system is proven using the Lyapunov method and LaSalle’s invariance principle. Through extensive experimental simulations, the proposed control strategy demonstrates good control performance.

The collisional electron spectroscopy method for analyzing and determining gaseous impurities was further developed to realize the operation in an open environment. In addition, the method not only facilitates the registration of the impurity components, but also the reactive radicals generated from the discharge reaction. The sandwich-like discharge structure was used to generate a stable, non-local, negative glow equipotential plasma in an open environment, and the I–V characteristic curve of the plasma was collected using an additional sensor electrode. The collisional electron spectroscopy was obtained from the first derivative of the probe current I with respect to the probe potential V by adding a diffusion function to correct it. In addition, our experiment verifies the reliability of the sink theory.

Plasma antenna systems consisting of discharge elements have great practical application prospects due to their ability to quickly adjust parameters over a wide range. In this work, the radiation patterns of a 30 mm long linear antenna surrounded by 16 standard T8 fluorescent lamps were measured by using a spectrum analyzer with a tracking generator. The radiation pattern of the system is measured by connecting the output of the spectrum analyzer tracking generator to a linear antenna and connecting the input of the spectrum analyzer to the receiving broadband horn antenna. The work features experimental measurements over a wide frequency range of 0.5 to 1.5 GHz and a wide discharge with current values from 35 to 200 mA. The specific frequency band and uniquely selected geometry allowed for the investigation of both the in-phase and out-of-phase antenna modes, while some modes were found to have a narrow directional radiation pattern, within 50 degrees, with a beam width of −3 dB. The parameters of the gas-discharge plasma were also evaluated using drift theory, as well as using the microwave transmission of the 20 GHz signal. The electron density value corresponding to the used discharge currents was approximately from 4 × 1011 to 7 × 1010 cm−3.