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Objective. In this work, we propose a content-based image retrieval (CBIR) method for retrieving dose distributions of previously planned patients based on anatomical similarity. Retrieved dose distributions from this method can be incorporated into automated treatment planning workflows in order to streamline the iterative planning process. As CBIR has not yet been applied to treatment planning, our work seeks to understand which current machine learning models are most viable in this context. Approach. Our proposed CBIR method trains a representation model that produces latent space embeddings of a patient’s anatomical information. The latent space embeddings of new patients are then compared against those of previous patients in a database for image retrieval of dose distributions. All source code for this project is available on github. Main results. The retrieval performance of various CBIR methods is evaluated on a dataset consisting of both publicly available image sets and clinical image sets from our institution. This study compares various encoding methods, ranging from simple autoencoders to more recent Siamese networks like SimSiam, and the best performance was observed for the multitask Siamese network. Significance. Our current results demonstrate that excellent image retrieval performance can be obtained through slight changes to previously developed Siamese networks. We hope to integrate CBIR into automated planning workflow in future works.

In this paper,we study the quantum size effects in multilayer graphene sheets using first principles methods within the framework of density functional theory. Four different types of functionals are adopted respectively to describe the van der Waals interactions between graphene layer sheets: the DFT-GGA(PBE), the DFT-D2, the vdW-DF and the optPBE-vdW. By inspecting the binding energy as a function of increasing graphene layers, we find that the PBE functional can not well describe the van der Waals interactions between different layers of graphene sheets. In contrast, the other three methods exhibit similar results with monotonic increasing binding energy as a function of graphene layers towards the bulk limit, concluding that the layered graphene structure is stabilized by van der Waals interactions. The density of states at zero temperature indicate that the multilayer graphene sheets is a semi-metal, which is independent of sheet layers number. The finite temperature (about 200 K) density of states at Fermi surface are studied as a function of the number of stacking graphene layers. The systematic oscillating behavior of finite temperature density of states between odd and even number of layers is a demonstration of quantum size effects. The Fermi wavelength will converge to two times the inter-layer distance of graphite, which is consistent with the theory describing the motion of particles in a quantum well. Finally, we study the adsorption of single H atom on multilayer graphene sheets to test the role of quantum size effects. The adsorption energies and the vibration frequencies are calculated for comparison with experiments. Our results shed light on understanding the stacking process of multilayer graphene in vacuum both theoretically and experimentally.

GH2132 superalloy performances excellent properties, such as the good rupture strength and yield strength below 923K, the fine processing plasticity and the good welding properties. The warm working behavior of GH2132 superalloy at 673 K – 773K is investigated by a thermal simulator in this paper. The results show that the worm working effects at the center of specimen is the most significant compared with other positions. The deformation temperature and strain rate is the key parameters significantly affecting the warm working behavior. The increase of the temperature enhances the recovery softening effect, which reduces the stress and the work hardening effect slightly. The deformation heat is significant with the increasing strain rate, which results in the work hardening behavior does not change markedly. This study provides an important reference for the worm forming of GH2132 superalloy.

A self-powered solar-blind ultraviolet (UV) photodetector (PD) was successfully constructed on a Ga2O3/Bi2WO6 heterojunction, which was fabricated by spin-coating the hydrothermally grown Bi2WO6 onto MOCVD-grown Ga2O3 film. The results show that a typical type-I heterojunction is formed at the interface of the Ga2O3 film and clustered Bi2WO6, which demonstrates a distinct photovoltaic effect with an open-circuit voltage of 0.18 V under the irradiation of 254 nm UV light. Moreover, the Ga2O3/Bi2WO6 PD displays excellent photodetection performance with an ultra-low dark current of ∼ 6 fA, and a high light-to-dark current ratio (PDCR) of 3.5 × 104 in self-powered mode (0 V), as well as a best responsivity result of 2.21 mA/W in power supply mode (5 V). Furthermore, the PD possesses a stable and fast response speed under different light intensities and voltages. At zero voltage, the PD exhibits a fast rise time of 132 ms and 162 ms, as well as a quick decay time of 69 ms and 522 ms, respectively. In general, the newly attempted Ga2O3/Bi2WO6 heterojunction may become a potential candidate for the realization of self-powered and high-performance UV photodetectors.

Many researchers have studied the application of low temperature plasma in soil remediation, but most focus on the degradation efficiency of a specific pollutant, and less attention is paid to the development and evolution process of plasma behind the soil remediation. In this paper, the possible mechanism behind soil discharge under pulse voltage is studied from the perspectives of electricity and optics. The electrical and optical analyses show that the soil discharge under pulse voltage mainly exists at the rising stage of pulse voltage, and the existence time is related with the pulse voltage amplitude. At the same time, the relative intensity of active substances (•OH, H, O Ⅱ and N Ⅰ), vibration temperature and rotational temperature are obtained by using the emission spectrum, which demonstrate that high pulse voltage can increase the concentration of active substances, vibration temperature and rotational temperature.

With the gradual improvement of optical interconnection technology’s requirements for high-speed broadband transmission of data, multidimensional multiplexing technology must be used to meet the application scenarios. Among them, polarization multiplexing technology has opened up a higher multiplexing dimension, and the application prospects are very broad. Polarization beam splitters have received a lot of attention as a key device in polarization multiplexing technology. The polarization multiplexer designed by traditional design methods with the help of classical theory and empirical calculation generally has deficiencies such as excessive volume and complex design, which is not conducive to large-scale integration, and the introduction of inverse design can effectively solve this problem and improve design efficiency. In this paper, the polarization beam splitter is implemented by using the inverse design, which can realize the output of the modes TE0 and TM0 in the bus waveguide from the respective regional waveguides, and the integration of TE0 and TM0 in the respective branch waveguides into the fusion transmission in the bus waveguide, with a size of only 2.4μm × 2μm. At the same time, simulation experiments show that the insertion loss of the device in the operating wavelength range of 1520nm to 1580nm is less than 1.4dB, and the crosstalk value between channels is almost negligible because the core layer of 220nm is difficult to achieve polarization rotation.

Corona discharge, as a common means to obtain non-equilibrium plasma, can generally obtain high-concentration plasma by increasing discharge points to meet production needs. However, the existing numerical simulation models used to study multi-point corona discharge are all calculations of small-scale space models, which cannot obtain the distribution characteristics of plasma in large space. Based on our previous research, this paper proposes a hybrid model for studying the distribution of multi-point discharge plasma in large-scale spaces, which divides the computational domain and computes separately with the hydrodynamic model and the ion mobility model. The simulation results are verified by a needle–ball electrode device. Firstly, the electric field distribution and plasma distribution of the needle electrodes with single tip and double tips are compared and discussed. Secondly, the plasma distribution of the needle electrode with the double tip at different voltages is investigated. Both computational and experimental results indicate that the charged particle concentration and current of the needle electrode with double tips are both twice as high as those of the needle electrode with a single tip. This model can extend the computational area of the multi-point corona discharge finite element model to the sub-meter (25 cm) or meter level, which provides an effective means to study the plasma distribution generated by multiple discharge points in large-scale space.

A new method of power feedback control for the lower hybrid wave (LHW) systems on the experimental advanced superconducting tokamak (EAST) is presented. Different methods are applied to control the power of two LHW systems with different frequency at 2.45 GHz and at 4.6 GHz, respectively. The old method is applied to control the 4.6 GHz LHW power through the exciter of klystrons, and the new one is used to control the 2.45 GHz LHW power through the high voltage power supply (HVPS) system. The new method has been applied in EAST and successfully assisted the development of relevant experiments such as loop voltage control, q profile control.

Linear electromagnetic actuators (LEAs) are widely used in tokamaks, but they are extremely sensitive to and are prone to fail in a high-strength stray magnetic field (SMF), which is usually a concomitant with tokamaks. In this paper, a multi-physics coupling analysis model of LEA, including magnetic field, electric circuit and mechanical motion, is proposed, and the dynamic characteristics of LEAs in SMFs are studied in detail based on the proposed model. The failure mechanism of LEAs in SMFs is revealed, and the influence of SMFs on the dynamic performance of LEAs is studied and quantified. It is shown that the failure threshold of the LEA selected in this work under the rated condition is 27 mT and 14 mT in the positive and negative direction, respectively. Under a typical SMF of 10 mT in the negative direction, the closing time of the LEA will be extended by 40%, while its opening time will be shortened by about 10%. Experimental tests are also conducted, which verify the validity of the proposed model and the analysis results. This paper provides a basis for the diamagnetic optimization design of LEA, and it is of great significance to ensure the reliable operation of the tokamak.

Garnet-type solid-state electrolytes (SSEs) are particularly attractive in the construction of all-solid-state lithium (Li) batteries due to their high ionic conductivity, wide electrochemical window and remarkable (electro)chemical stability. However, the intractable issues of poor cathode/garnet interface and general low cathode loading hinder their practical application. Herein, we demonstrate the construction of a reinforced cathode/garnet interface by spark plasma sintering, via co-sintering Li6.5La3Zr1.5Ta0.5O12 (LLZTO) electrolyte powder and LiCoO2/LLZTO composite cathode powder directly into a dense dual-layer with 5 wt% Li3BO3 as sintering additive. The bulk composite cathode with LiCoO2/LLZTO cross-linked structure is firmly welded to the LLZTO layer, which optimizes both Li-ion and electron transport. Therefore, the one-step integrated sintering process implements an ultra-low cathode/garnet interfacial resistance of 3.9 Ω cm2 (100 °C) and a high cathode loading up to 2.02 mAh cm−2. Moreover, the Li3BO3 reinforced LiCoO2/LLZTO interface also effectively mitigates the strain/stress of LiCoO2, which facilitates the achieving of superior cycling stability. The bulk-type Li|LLZTO|LiCoO2-LLZTO full cell with areal capacity of 0.73 mAh cm−2 delivers capacity retention of 81.7% after 50 cycles at 100 μA cm−2. Furthermore, we reveal that non-uniform Li plating/stripping leads to the formation of gaps and finally results in the separation of Li and LLZTO electrolyte during long-term cycling, which becomes the dominant capacity decay mechanism in high-capacity full cells. This work provides insight into the degradation of Li/SSE interface and a strategy to radically improve the electrochemical performance of garnet-based all-solid-state Li batteries.

Due to the problem of single factor and no benchmark in the design of image characteristic index, the measurement results of machine vision-based grinding surface roughness measurement are greatly influenced by the light source brightness, and the accuracy is limited. To address this problem, a method based on the combination of a full-reference (FR) image quality algorithm visual saliency-induced index (VSI) and a backward propagation (BP) neural network for grinding surface roughness measurement is proposed. First, the VSI is applied to characterize grinding surface roughness. Its performance is then compared with the mainstream color image-based indices. Meanwhile, the ability of anti-interference to light source is analyzed for the VSI. Furthermore, in order to improve the prediction accuracy, the BP neural network is selected and applied to construct the roughness prediction model. The experimental results show that the VSI has significant advantages in the abilities of measurement accuracy and anti-interference to light source brightness levels. BP can significantly improve the prediction accuracy for VSI.

To meet the stringent requirements of the fusion power supply for large-scale fusion devices, the J-TEXT engineering team has carried out key technology research and applications in several important directions of fusion power supply. This article presents the advances made by the J-TEXT engineering team in recent years in the following areas: (1) a high-voltage power supply for an auxiliary heating system; (2) a breakdown protection device for an auxiliary heating power supply; (3) magnetic field compatibility; (4) a high-voltage pulsed power supply for a field-reversed configuration; (5) a large physics experimental facility control system. The research backgrounds, technical progress, test results, applications, summaries and prospects are described in detail in each part. These innovative research results and valuable engineering experience can promote the progress of fusion power supply technology, and also lay a foundation for the development of power supplies with higher parameters in the future.

After the B-phase of the 500kV transformer was replaced, the three-phase voltage on the 35kV low-voltage side was imbalanced and the neutral point displacement voltage was relatively high during the start-up test. For this problem, firstly, the calculation method of neutral point displacement voltage is given through the method of vector analysis and equivalent circuit, and the reasons for the imbalance of the three-phase voltage are analyzed. According to the measured parameters, the PSCAD/EMTDC power system simulation software is used to establish a model, and the steady-state operating characteristics of the system are simulated and calculated. Theoretical analysis and simulation calculation have determined that the cause of the imbalance of the three-phase voltage is the inconsistency between the ground capacitance of the low-voltage winding and the capacitance between the high-voltage and low-voltage windings of the B-phase transformer than that of the A-phase and C-phase. The impact of the capacitance between the high-voltage and low-voltage windings of the transformer is far greater than the capacitance of the low-voltage windings to ground on the imbalance of three-phase voltage to ground on the low-voltage side of the transformer.

In order to accumulate preliminary data of mechanical characteristics of the fast switch, and to verify whether the design parameter requirements are met. This paper selects three prototypes and three engineering prototypes respectively, collects and analyzes mechanical characteristics of three engineering machines before and after the prototype test, the life prototype before and after the life test, the capacity prototype before and after the capacity test. It is proved that the opening and closing time of quick-switch prototype and engineering prototype meet design requirements. Data results measured by all parties are in good agreement. Among three prototypes, the maximum phase difference between fast switch opening time, opening speed, closing time, and closing speed is only 10.7%, 6.7%, 8.8%, and 9.5%. In three-phase engineering prototype, the maximum inter-phase difference of fast switch opening time, opening speed, closing time, and closing speed is only 8.3%, 4.9%, 3.5%, and 7.8%.

Simultaneous localization and mapping (SLAM) is the basis for many robotic applications. Most SLAM algorithms are based on the assumption that the scene is static. In real-world applications, moving objects are inevitable, which will greatly impact the ego-pose estimation accuracy. This paper presents DyStSLAM, a visual SLAM system with a stereo configuration that can efficiently identify moving objects and accomplish dynamic data association. First of all, DyStSLAM extracts feature points, estimates the disparity map, and performs instance segmentation simultaneously. Then, the obtained results are combined to estimate the motion confidence and discriminate between moving objects and static ones. A confidence based matching algorithm is proposed to associate dynamic objects and estimate the pose of each moving object. At the same time, static objects are used to estimate the pose of the camera. Finally, after nonlinear optimization, a sparse point cloud map of both static background and dynamic objects is constructed. Compared with ORB-SLAM2, the proposed method outperforms by 31% for absolute trajectory error on the KITTI dataset.

Micro-force measurement with high resolution, accuracy, and reliability is of interest in a broad range of applications including gravitational-wave detection, intelligent healthcare, bionic robotics, and micromanipulation. Herein, the researchand development in recent years of micro-force sensors based on various principles is reviewed thoroughly, presenting their characteristics and applications, as well as summarizing their advantages and limitations. The most indispensable component of force sensors, elastic sensitive elements, is underlined. Next, four kinds of not widely used but promising sensors are also introduced briefly. Finally, the traceable reference forces are analyzed, concluding with a future perspective into the corresponding challenges and opportunities of micro-force sensors for future research. This review aims at providing references for developing micro-force sensors and improving their performance.

Small field dosimetry is significantly different from the dosimetry of broad beams due to loss of electron side scatter equilibrium, source occlusion, and effects related to the choice of detector. However, use of small fields is increasing with the increase in indications for intensity-modulated radiation therapy and stereotactic body radiation therapy, and thus the need for accurate dosimetry is ever more important. Here we propose to leverage machine learning (ML) strategies to reduce the uncertainties and increase the accuracy in determining small field output factors (OFs). Linac OFs from a Varian TrueBeam STx were calculated either by the treatment planning system (TPS) or measured with a W1 scintillator detector at various multi-leaf collimator (MLC) positions, jaw positions, and with and without contribution from leaf-end transmission. The fields were defined by the MLCs with the jaws at various positions. Field sizes between 5 and 100 mm were evaluated. Separate ML regression models were generated based on the TPS calculated or the measured datasets. Accurate predictions of small field OFs at different field sizes (FSs) were achieved independent of jaw and MLC position. A mean and maximum % relative error of 0.38 ± 0.39% and 3.62%, respectively, for the best-performing models based on the measured datasets were found. The prediction accuracy was independent of contribution from leaf-end transmission. Several ML models for predicting small field OFs were generated, validated, and tested. Incorporating these models into the dose calculation workflow could greatly increase the accuracy and robustness of dose calculations for any radiotherapy delivery technique that relies heavily on small fields.

Efficient collection of water from fog can effectively alleviate the problem of water shortages in foggy but water-scarce areas, such as deserts, islands and so on. Unlike inefficient fog meshes, corona discharge can charge water droplets and further enhance the water-collecting effect. This study proposes a novel multi-electrode collecting structure that can achieve efficient and direction-independent water collection from fog. The multi-electrode structure consists of three parts: a charging electrode, an intercepting electrode and a ground electrode. Four types of water-collecting structures are compared experimentally, and the collection rates from a traditional fog mesh, a wire-mesh electrode with fog coming from a high-voltage electrode, a wire-mesh electrode with fog coming from a ground electrode and a multi-electrode structure are 2–3 g h−1, 100–120 g h−1, 60–80 g h−1 and 200–220 g h−1, respectively. The collection rate of the multi-electrode structure is 100‒150 times that of a traditional fog mesh and 2–4 times that of a wire-mesh electrode. These results demonstrate the superiority of the multi-electrode structure in fog collection. In addition, the motion equation of charged droplets in an electric field is also derived, and the optimization strategy of electrode spacing is also discussed. This structure can be applied not only to fog collection, but also to air purification, factory waste gas treatment and other fields.

There is an increasting demand for homogeneous magnetic fields (HMFs) as an exposure resource for electrical immunity tests, biomedical experiments, etc. The design of conventional HMF generators, such as Helmholtz and Barker coils, only focuses on the field homogeneity at the coil center, which leads to limitations in the available HMFworkspace. In this paper, based on a comprehensive definition of the HMF, optimized circular three-coil and four-coil systems are analysed through an optimization method. By standardizing the coil parameters to the HMF parameters, it is easy to scale the coil systems to the desired HMF. In addition, two sets of concise formulae are presented as practical design tools. Compared to Barker coils, the proposed optimized coil systems enable a reduction in both total electrical power and conductor mass by 14.9%–33.6%. Numerical simulations and experimental tests are implemented to show the effectiveness of the theoretical results and the improvement in coil performance.

Here, we report on heteroepitaxial α-Ga2O3 MOSFETs with a breakdown voltage (BV) of 2.3 kV at a specific on-resistance of 335 mΩ cm2. High-quality α-Ga2O3 layers were grown on a sapphire substrate via halide vapor-phase epitaxy (HVPE). A stack of Ti/Al/Ni/Au was used for the S/D electrode, exhibiting significantly reduced contact resistance as compared with a conventional Ti/Au stack. Consequently, the record BV and mobility of 20.4 cm2 V−1 s−1 were achieved. Moreover, a consistent critical field of 1 MV cm−1 was obtained for variable LGD. Our results are superior to recently reported heteroepitaxial α-/β-Ga2O3 MOSFETs, which is promising toward HVPE α-Ga2O3 based power devices.

With the rapid development of the Internet and artificial intelligence era, how to obtain effective information is particularly important in the complex network world. In order to obtain a real movie viewing experience and provide some reference for other users, this article is based on the Python language, taking the popular movie “Shuimen bridge of Changjin Lake” as an example on Douban website, and using web crawler technology to comment and rate users, etc. Relevant data is crawled, the crawled data is the object of analysis, and data visualization processing is carried out to more intuitively show the true feelings of moviegoers. The results show that the film meets the expectations of the public and is worthy of recommendation.

Aiming at the problems of insufficient feature extraction, slow speed and low accuracy of traditional machine learning methods, a soybean variety identification method based on improved ResNet18 hyperspectral image was proposed. This method extracts more effective detail features by decomposing the large convolution kernel, and changes the connection of residual structure and introduces the BN layer optimization network to make the feature extraction more sufficient. The perception of soybean hyperspectral image recognition is enhanced by adding multi-scale feature extraction module. The experimental results show that the recognition accuracy of this method reaches 97.36 %, which is higher than Nasnet large and Resnet18 models, and the robustness of the model is further enhanced, which can provide reference for soybean variety recognition.

The existence of dual flow potentials is well established in mathematical theory of plasticity since the seminal work by Hill in 1987. For a metal undergoing plastic flow, a flow stress potential is used to compute its plastic strain increments when the applied yield stress is known. On the other hand, the corresponding dual flow strain-rate potential is used to compute the stress on the flow surface when the plastic strain increments are given. This work examines some issues associated with plasticity modeling using non-quadratic dual flow potentials. Unlike the quadratic case where flow stress and strain-rate potentials are the exact dual to each other, it is often difficult if not impossible to obtain analytically the dual of a non-quadratic flow stress or strain-rate potential. The study instead focuses on formulating and assessing various non-quadratic pseudo dual flow potentials that approximate the actual flow surfaces in either stress or strain-rate space. The difference and connection between the yield surface and flow surface in non-associated plasticity are also investigated. Although only one of the dual flow potentials is actually needed for their applications in associated and non-associated plasticity modeling, the unique advantage of having both dual flow potentials on hand even in their pseudo forms is pointed out for new computational analyses.

Collisional-merging is a way to form high-performance field-reversed configuration (FRC) plasma. An experiment device named HUST-FRC (HFRC) is under construction in Huazhong University of Science and Technology, which will be used to investigate the FRC formation through collisionalmerging. In this research, a magnetohydrodynamics simulation software called USim is used to study the effect of the initial density of plasma, the amplitude of the bias magnetic field, the configuration of the bias field, the rise time of the main field and the magnetic field ripple on the plasma parameters to facilitate the design and operation of HFRC. Preliminary simulation results show that cusp configuration, lower ripple, higher initial density, an initial bias field of −0.15 T or −0.2 T, and a rise time of 4 μs are conducive to the formation of high-performance FRC plasma in the HFRC device.

Considerable research efforts have been devoted to the study of the application of atmospheric discharge in soil remediation. Most of them focused on how to improve the degradation efficiency of specific pollutants. In contrast, the generation and development of discharge in soil is less studied, which restricts the widespread application of soil remediation. Pulse voltage is widely used to trigger discharge in soil, but the requirement for the power supply is relatively high. The current paper proposes a new form of discharge voltage, with positive pulse voltage superimposed on DC bias. The results show that the existence of DC component can effectively lower the required pulse voltage and enlarge the active corona volume, in which area most ionization and excitation happens. The characteristics of corona discharge in soil under DC voltage only, pulse voltage only and superimposed voltage with various voltage components are discussed in detail, according to the volt-ampere characteristics and discharge images from a series of experiments. The mechanism behind the experimental phenomenon are also discussed.

Cogging torque is one of the main factors that deteriorate the performance of permanent magnet motor. In order to reduce the cogging torque of built-in permanent magnet motor, a method of optimizing Rib and DminMag to reduce groove torque of built-in permanent magnet motor was proposed. Firstly, the relationship between Rib and DminMag and groove torque is analyzed through the expression of groove torque. Secondly, the optimal Rib and DminMag were found by finite element parametric calculation, and compared with the pre-optimization groove torque, the groove torque was significantly reduced. Finally, the main performance of motor before and after optimization is not significantly reduced.

In the last two years, three major technical improvements have been made on J-TEXT in supporting of the expanded operation regions and diagnostic capabilities. (1) The successful commission of the 105 GHz/500 kW/1 s electron cyclotron resonance heating (ECRH) system increasing the core electron temperature from 0.9 keV up to around 1.5 keV. (2) The poloidal divertor configuration with an X-point in the high-field side has been achieved. In particular, the 400 kW electron cyclotron wave has also been successfully injected into the diverted plasma. (3) A 256-channel electron cyclotron emission imaging diagnostic system and two sets of four-channel Doppler backscattering diagnostics have been successfully developed on J-TEXT, allowing detailed measurement of the electron temperature and density fluctuations for turbulence and MHD research. The locked mode (LM), especially the 2/1 LM, is one of the biggest threats to the plasma operation. Both the thresholds of 2/1 and 3/1 LM are observed to vary non-monotonically on electron density. The electrode biasing was applied successfully to unlock the LM from either a rotating or static resonant magnetic perturbation (RMP) field. In the presence of 2/1 LM, three kinds of standing wave (SW) structures have been observed to share a similar connection to the island structure, i.e. the nodes of the SWs locate around the O- or X-points of the 2/1 island. The control and mitigation of disruption is essential to the safe operation of ITER, and it has been systematically studied by applying a RMP field, massive gas injection (MGI) and shattered pellet injection on J-TEXT. When the RMP-induced 2/1 LM is larger than a critical width, the MGI shutdown process can be significantly influenced. If the phase difference between the O-point of LM and the MGI valve is +90° (or −90°), the penetration depth and the assimilation of impurities can be enhanced (or suppressed) during the pre-thermal quench (TQ) phase and result in a faster (or slower) TQ. A secondary MGI can also suppress the runaway electron (RE) generation, if the additional high-Z impurity gas arrives at the plasma edge before TQ. When the secondary MGI has been applied after the formation of the RE current plateau, the RE current can be dissipated, and the dissipation rate increases with the injected impurity quantity but saturates with a maximum of 28 MA s−1. The non-local transport is experimentally observed in the ion transport channel. The electron thermal diffusivity significantly increases with the ECRH power. Theoretical work shows that significant intrinsic current can be driven by electromagnetic turbulence, and the robust formation mechanism of the E × B staircase is identified from the Hasegawa–Wakatani system.

The coalescence of droplets on the discharge electrode surface in high humidity environments has rarely been studied, which may affect discharge characteristics. Meanwhile, directional transport of droplets is of great significance for many applications ranging from fluidic processing to thermal management. Here, corona discharge in a needle-plate electrode is adopted to explore the coalescence rule of droplets attached on the discharge electrode surface in a high-humidity environment, and to realize the counterflow of droplets. The experimental results show that the number of coalesced droplets on the needle electrode surface reaches the maximum under −7.5 kV at relative humidity ∼94% and ambient temperature ∼20 °C. When the applied voltage increases from −6 kV to −11 kV, the droplet moves up 2.76 mm in 5 s. The size of the attached droplet depends on the balance of coalescence and evaporation. The coalescence is mainly attributed to the dielectrophoretic force caused by the high electric field gradient. The evaporation is related to the ionic wind generated by the corona discharge. With regard to the counterflow phenomenon of the droplet, we speculate that the high concentration gradient of positive ions near the needle electrode provides a driving force for the negatively charged droplets. Meanwhile, the electrons and negative ions below the needle tip offer a repulsive force to the droplet. The shape and moving direction of the droplet attached to the needle surface can be manipulated by changing the voltage applied to the needle electrode, which shows the potential application value in realizing the self-cleaning of electrodes, liquid lenses and so on.

With the development of technology, modular independent suspension technology has been widely applied on high-movement off-road platforms in the developed world because of the characteristics of offline assembly and full-body lifting. At the same time, after the breakthrough of key techniques such as the stiffness spiral springs, the high dissipation of the shock absorbers, the lightweight of double-wishbone steering mechanism and the non-maintenance bearing, the ability to carry the off-road mobility and armor protection of the military vehicles have been significantly increased. In this case, the application of the modular independent suspension and its current state around the world was explained, that the development of this technology is of great significance to the off-road maneuvering of our military equipment was also represented in this paper.

It has been indicated the critical transition temperature (T c) of MgB2 decreases with the increase of hydrostatic pressure, but this is a comprehensive T c change after the multiaxial strain, and the influence of strain on T c is not fully understood. In this paper, based on the McMillan superconducting calculation formula and the first-principles density functional theory, the T c change and the properties of MgB2 such as energy band, Fermi surface, differential charge density, and phonon dispersion under uniaxial strain were studied, and the relationship between uniaxial strain and these properties was analyzed. The calculated T c of MgB2 at zero strain was 38.35 K, which is in good agreement with the experimental value of 39 K. When the a-axis strain was 1%, the T c value could increase to 49.7 K, and there was a further improvement trend. When the a-axis compression strain was −1%, T c decreases to 31.52 K. When the c-axis tension–compression strain was applied, the change of T c value was small. Further analysis showed that the impact of a-axis strain on the differential charge density, electronic band structure, phonon dispersion, and other properties of MgB2 was significantly greater than that of c-axis strain, and the influence of these properties on T c was discussed. The work in this paper has certain theoretical and guiding significance for preparing MgB2 with higher T c and the study of the effect of uniaxial strain on T c of superconducting materials.

The interaction between a permanent magnet (PM) assumed as a magnetic dipole and a flat high-temperature superconductor (HTS) is calculated by the advanced frozen-image model. When the dipole vertically moves above the semi-infinite HTS, the general analytical expression of vertical force and that of torque are obtained for an arbitrary angle between the magnetization direction of the PM and the c axis of the HTS. The variations of the force and torque are analyzed for angle and vertical movements in both zero-field cooling (ZFC) condition and field cooling (FC) condition. It is found that the maximum vertical repulsive or attractive force has the positive or negative cosine relation with the angle. However, the maximum torque has the positive or negative sine relation. From the viewpoint of the rotational equilibrium, the orientation of the magnetic dipole with zero angle is deemed to be an unstable equilibrium point in ZFC, but the same orientation is considered as a stable equilibrium point in FC. In addition, both of the variation cycles of the maximum force and torque with the angle are π.