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Pressure induced insulator to metal transition followed by the appearance of superconductivity has been observed recently in inorganic quantum spin liquid candidate NaYbSe2. In this letter, we study the properties of isostructural compound NaYbS2 under pressure. It is found that the resistance of NaYbS2 single crystal exhibits an insulating state below 82.9 GPa, but with a drop of more than six orders of magnitude at room temperature. Then a minimum of resistance is observed at about 100.1 GPa and it moves to lower temperature with further compression. Finally, a metallic state in the whole temperature range is observed at about 130.3 GPa accompanied a non-Fermi liquid behavior below 100 K. The insulator to metal transition, non-monotonic resistance feature and non-Fermi liquid behavior of NaYbS2 under pressure is similar to those of NaYbSe2, suggesting that these phenomena might be the universal properties in NaLnCh2 (Ln = rare earth, Ch = O, S, Se) system.

Owing to their unique material design-ability and excellent weight reduction properties of carbon fibre reinforced polymers(CFRP), commercial aircraft OEMs have been innovating design and manufacturing approaches to wider the application of advanced composites. In this paper, the bearing capacity of composite hat-stiffened panels is determined by an improved engineering calculation method and numerical analysis method. The effectiveness of both methods is verified by the test. The advantage of the engineering estimation method is simple and fast, which is suitable for the parametric analysis of the structure in the preliminary design phase. The finite element method can better simulate the test process and is suitable for the comprehensive evaluation of structural strength. The combination of the two methods has a high reference value for rapid design and selection.

Severe matrix effects and high signal uncertainty are two key bottlenecks for the quantitative performance and wide applications of laser-induced breakdown spectroscopy (LIBS). Based on the understanding that the superposition of both matrix effects and signal uncertainty directly affects plasma parameters and further influences spectral intensity and LIBS quantification performance, a data selection method based on plasma temperature matching (DSPTM) was proposed to reduce both matrix effects and signal uncertainty. By selecting spectra with smaller plasma temperature differences for all samples, the proposed method was able to build up the quantification model to rely more on spectra with smaller matrix effects and signal uncertainty, therefore improving final quantification performance. When applied to quantitative analysis of the zinc content in brass alloys, it was found that both accuracy and precision were improved using either a univariate model or multiple linear regression (MLR). More specifically, for the univariate model, the root-mean-square error of prediction (RMSEP), the determination coefficients (R 2) and relative standard derivation (RSD) were improved from 3.30%, 0.864 and 18.8% to 1.06%, 0.986 and 13.5%, respectively; while for MLR, RMSEP, R 2 and RSD were improved from 3.22%, 0.871 and 26.2% to 1.07%, 0.986 and 17.4%, respectively. These results prove that DSPTM can be used as an effective method to reduce matrix effects and improve repeatability by selecting reliable data.

Due to the high volatility and randomness of PV power generation, fast change frequency, limited data samples and poor data conditions, the reliability, stability and economy of grid operation are affected seriously. Therefore, the accurate prediction of PV power generation can mitigate the impact of its volatility on the stability of national grid power operations. And it improves PV consumption capacity and enhances the security of microgrid and distribution grid interconnection. This paper first proposed a PV power prediction method. Secondly, through the introduction and analysis of three types of prediction methods, the first type of prediction is selected using statistical analysis and modeling methods. Thirdly, an optimized Elman neural network-based PV power prediction model is proposed to allow accurate prediction of PV power prediction. Finally, an example is given to verify the advantages of the algorithm.

High voltage cable line is an important part of power grid; its stable operation is of great significance to urban power system. This paper proposed a high voltage cable insulation monitoring system using traveling wave. The travelling wave data are collected by high precision satellite timing signal and an on-line fault location system for high voltage cable is designed.

Virtual power plants can participate in power market transactions by combining wind and solar power generation and energy storage technologies, They participate in energy market transactions for aggregating distributed energy and user-side resources, Meanwhile, the carbon trading market is an effective tool to control the greenhouse effect, As a market subject with unlimited potential, VPP of industrial park plays its environmental benefits by participating in the carbon trading market, It is able to promote the growth of VPP benefits and reduce carbon emissions, Firstly, this paper introduces the composition of virtual power plants and the carbon trading market, Secondly, this paper puts forward the influence of the uncertainty of wind turbines on virtual power plants, Thirdly, a virtual power plant model is build under the uncertainty of wind turbines, Finally, the operation of virtual power plants is optimized considering carbon trading, so as to maximize the benefits and explore the carbon reduction capacity of virtual power plants

The integration of an Energy Storage System (ESS) is difficult to commercialize within the current Chinese market mainly because of the lacking of supporting policy and breakthrough technologies. However, it is considered an appropriate approach in a certain circumstance, for instance, in a remote rural area. This work presents a power-balanced ESS integration model and its control method. By using a rural distributed network in southern China, the results show that the proposed model is able to improve the three-phase power imbalance issue.

Whilst the thin-walled composite structures have been widely used to build the primary components in aircraft, Low-Velocity Impact (LVI) can cause severe intra-laminar and inter-laminar damage in the composite material, reducing the mechanical performance of these components. This paper presents an experimental study on the compressive failure behavior of a Single Hat-Stiffener Panel (SHSP) with two typical flaws, i.e., impact-induced damage and skin/stiffener debonding. LVI tests were performed to introduce the damage around the radius edge of the stiffener and the center of the flat skin panel, respectively, while the skin/stiffener debonding was introduced to the SHSP by artificially embedding a PTFE film at the skin/stiffener interface during autoclave curing. The impact energy to cause Barely Visible Impact Damage (BVID) was determined to be 22 J for the thin SHSP configuration. Whilst the considerable damage area was detected by the ultrasonic scan for the thick SHSP at an energy level of 35 J, the impact-induced indentation was not visually detectable (

Based on Generalized Lorenz-Mie Theory (GLMT), the scattering phenomenon caused by Bessel beam irradiation on metal particles is studied. The order and polarization mode of Bessel beam, as well as the influence of the size of metal particles on the total intensity distribution of the light field around metal particles are investigated by using the software simulation calculation. The results show that for spherical metal particles of the same size, the higher order Bessel beam is more likely to bypass the metal particles in the forward propagation, while the lower order Bessel beam bypassed the particles in the propagation is related to the beam polarization mode. The results have potential applications in microscopy super-resolution imaging and detection of tiny particles.

With the development of computed tomography (CT) imaging technology, it is possible to acquire multi-energy data by spectral CT. Being different from conventional CT, the X-ray energy spectrum of spectral CT is cutting into several narrow bins which leads to the result that only a part of photon can be collected in each individual energy channel, which cause the image qualities to be severely degraded by noise and artifacts. To address this problem, we propose a spectral CT reconstruction algorithm based on low-rank representation and structure preserving regularization in this paper. To make full use of the prior knowledge about both the inter-channel correlation and the sparsity in gradient domain of inner-channel data, this paper combines a low-rank correlation descriptor with a structure extraction operator as priori regularization terms for spectral CT reconstruction. Furthermore, a split-Bregman based iterative algorithm is developed to solve the reconstruction model. Finally, we propose a multi-channel adaptive parameters generation strategy according to CT values of each individual energy channel. Experimental results on numerical simulations and real mouse data indicate that the proposed algorithm achieves higher accuracy on both reconstruction and material decomposition than the methods based on simultaneous algebraic reconstruction technique (SART), total variation minimization (TVM), total variation with low-rank (LRTV), and spatial-spectral cube matching frame (SSCMF). Compared with SART, our algorithm improves the feature similarity (FSIM) by 40.4% on average for numerical simulation reconstruction, whereas TVM, LRTV, and SSCMF correspond to 26.1%, 28.2%, and 29.5%, respectively., Comment: 21 pages, 9 figures

It has been verified that the discharge pulse generated by the pantograph-catenary system has the biggest impact on the high-speed EMU as the electromagnetic interference source. But the spectrum obtained from the existing pantograph discharge model does not contain high frequencies and is far from the measurement results. In this paper, a novel scheme based on Newton’s method and finite difference time domain (FDTD) algorithm was presented to solve this problem. Firstly, Newton’s method was utilized to solve the Habedank model, and the dynamic conductance of the arc was obtained. Then, the equivalent distributed parameter circuit model of the traction power supply system was established, which was solved by the FDTD and state variable method to obtain the time-domain waveform of the arc voltage. The significant features of this scheme are that it can realize the synchronous calculations of the arc dynamic conductance and the voltage responses along the catenary. Through this scheme, a stable arc voltage time domain waveform can be obtained, and the arc voltage spectrum is highly consistent with the test results.

At present, the trusted platform module (TPM) has been widely used in electricity, finance, transportation, and other industries, and its security has attracted much attention. The research on the side-channel attack (SCA) can be conducive to improving the security design technology of trusted platform modules. The side channel attack on the trusted platform module is studied from the initial differential power analysis (DPA) to the machine learning method. This paper introduces the deep learning techniques in SCA and proposes a new SCA technique based on deep learning. Firstly, on basis of the characteristics of SCA on TPM, we improve the convolutional neural network (CNN) models, including ResNet, VGG, and Google Net. Then, for the SM4 cipher implemented with and without countermeasures, we implement some attack experiments by exploiting the SCA based on various deep learning models and compare the experimental results with the DPA attack. The experiment results show that under the same circumstance, the SCA based on the deep learning method is more effective. We compare the effects of different CNN models and hyper-parameters to provide the basis and data for further research.

In order to investigate the relationship between the flow-field parameters outside the vehicle and the altitude, this paper takes the Atmospheric Reentry Demonstrator (ARD) with an angle of attack of –20° as the research object and adopts a two-temperature model coupled with the shear-stress transport k–ω turbulence model to focus on the variation of flow-field parameters including flow-field pressure, Mach number and temperature with the reentry altitude. It is found that the flow-field high-pressure region and low-Mach region both appear in the shock layer near the head of the ARD, while the maximum pressure of the surface appears on the windward side of the ARD’s head with a toroidal distribution, and the numerical magnitude is inversely proportional to the radius of the torus. With fluid through the shoulder of the ARD flow expansion plays a dominant role, the airflow velocity increases, the Mach number of the windward side of the rear cone increases and the flow-field pressure and surface pressure rapidly decrease. When the fluid passes through the shock layer, the translational–rotation temperature will increase before the vibration–electron temperature, there is a thermal non-equilibrium effect and the two temperatures will rapidly decrease again when approaching the surface of the ARD due to the existence of temperature gradient. At the same time, both the windward side of the shoulder and the back cover of the ARD suffer from a large thermal load and require thermal protection.

We report a significantly enhanced anomalous Hall effect (AHE) of Pt on antiferromagnetic insulator thin film (3-unit-cell La0.7Sr0.3MnO3, abbreviated as LSMO), which is one order of magnitude larger than that of Pt on other ferromagnetic (e.g. Y3Fe5O12) and antiferromagnetic (e.g. Cr2O3) insulator thin films. Our experiments demonstrate that the antiferromagnetic La0.7Sr0.3MnO3 with fully compensated surface suppresses the positive anomalous Hall resistivity induced by the magnetic proximity effect and facilitates the negative anomalous Hall resistivity induced by the spin Hall effect. By changing the substrate’s temperature during Pt deposition, we observed that the diffusion of Mn atoms into Pt layer can further enhance the AHE. The anomalous Hall resistivity increases with increasing temperature and persists even well above the Neel temperature (T N) of LSMO. The Monte Carlo simulations manifest that the unusual rise of anomalous Hall resistivity above T N originates from the thermal induced magnetization in the antiferromagnetic insulator.

The application of composite materials in the primary structures of large aircraft fuselage is a development trend in recent years. As an indispensable structure in design and structure selection, accurate and efficient evaluation of its performance is of great significance to reduce the research cost. In this paper, the bearing capacity of stiffened curved composite panel is calculated through an improved engineering calculation method, and the effectiveness of the method is verified by test, which provides technical support for the rapidly design and selection of stiffened curved composite panels.

As the global energy crisis and environmental pollution problems become increasingly severe, it is important to develop new energy capture and pollution management methods. Among these new technologies, photocatalysis has garnered significant interest because of its significant application prospects in harnessing pollution-free solar energy to degrade organic pollutants. From a fundamental scientific and technical perspective, improved optical frequency is a key research topic that provides a useful framework for studying the optical processes impacted by the local photonic environment. This type of study is especially pertinent because plasmonics emphasizes nonlinearity. Thus, near-infrared (NIR) catalysis has received considerable attention. In this review, we aimed to provide an integrated framework for NIR photocatalysis. We briefly introduce photocatalysis based on upconversion (UC) materials, including the efficiency of UC materials and the bination and energy transfer process between the semiconductor and UC particles as well as photoelectric response photocontrolled-delivery and photodynamic therapy based on NIR-responsive materials.

The proximity pulse Doppler radar (PPDR) possesses high-range resolution and has been widely used in short-range detection. Unfortunately, the detection performance is seriously deteriorated by interference. Therefore, a dynamic interference suppression method (DISM) based on a game model is proposed. In the DISM, three interference suppression strategies are proposed for different interference strategies. The first strategy is the deceptive interference suppression strategy via the identity recognition of the PPDR. The second is a barrage interference suppression strategy, which is realized via the recognition of the time-frequency joint features of the target and interference. The last strategy is to combine the previous two strategies. For optimal interference suppression performance, the DISM will dynamically choose an interference suppression strategy according to their payoffs, which effectively enables the PPDR to maintain the dominant position in the game with the interference source. The efficiency of the DISM at different interference and signal-to-interference-plus-noise ratios is proved by comparison with other methods.

Generally, construction real numbers are considered constructive real numbers that coherently relate to some construction approaches. The analysis of this paper primarily focuses on the perspectives of left numbers in the study of constructive reviews. The review of this essay created a general connection between different concepts put together through the discovery and consideration of the available references. That was based on the assessment and introduction of these concepts based on the conditions and perspectives of constructive mathematics. The paper’s analysis also discussed and utilized specific propositions to prove and simplify the overall findings of this study. Further, the results indicate that the context of constructive mathematics has an existing algorithm available in any constructive number. Through this, constructive mathematics can produce a corresponding Left (L) number under the assumption that equivalent Left numbers can be the output with equivalent constructive real numbers (CRN). The findings of this analysis indicates that there is an existing algorithms that defines any constructive real number in the context of constructive mathematics. Through such correspondent relationship can generate a corresponding Left number. That is based on the assumption that in the context of equivalent real numbers, the possible output in this context is equivalent to Left number. Additionally, this assessment extensively utilized the Spector sequence while proving that the converse statement is false. We further suggest that the study can introduce more individuals to the basic concepts and applications of theories in the analysis.

The demand for wearable sensors is vastly growing as it provides people the ability to monitor their daily activities, surrounding environment, and health conditions conveniently. The development of these sophisticated wearable sensors with specific- or multiple-function capacity largely depends on the innovation pace of fabrication technologies. This review focuses on the most recent development of micro/nanofiber fabrication technologies for fabricating wearable sensors, including drawing, spinning, coating, and printing. The basic working mechanisms are introduced, followed by some representative applications. Lastly, the perspectives of these advanced methods on the development of future wearable sensors are discussed. Agency for Science, Technology and Research (A*STAR) Ministry of Education (MOE) Nanyang Technological University National Research Foundation (NRF) Submitted/Accepted version This work was supported by the Fundamental Research Funds for the Central Universities (D5000220072), the National Key R&D Program of China (2021YFF0600905), the Singapore Ministry of Education Academic Research Fund Tier 2 (MOE2019-T2-2-127 and MOE-T2EP50120-0002), A∗STAR under AME IRG (A2083c0062), the Singapore Ministry of Education Academic Research Fund Tier 1 (MOE2019-T1- 001-103 (RG 73/19) and MOE2019-T1-001-111 (RG90/19)) and the Singapore National Research Foundation Competitive Research Program (NRF-CRP18-2017-02). This work was partly supported by the Schaeffler Hub for Advanced Research at NTU, under the ASTAR IAF-ICP Programme ICP1900093. This work was also supported by Nanyang Technological University.

GIL electrical parameters are different from overhead lines. With the increasing application of GIL in actual projects, the influence of GIL needs to be considered when calculating the short-circuit current of the power grid. In this paper, the calculation of three-phase short-circuit current is carried out for the EHV double-circuit overhead line on the same tower with GIL. First, the electrical parameters of EHV GIL are calculated. The positive sequence resistance, reactance and capacitance values of a typical GIL are calculated. Secondly, EMTP-ATP software is used to modelling and simulation. The influence of GIL length on the short-circuit current and the position of short-circuit fault is studied respectively. Finally, the influence of the GIL unit length modelling accuracy and the grounding mode of the metal shell on the short-circuit current is studied. The research results of this paper can provide a theoretical reference for GIL simulation modelling and the evaluation of the impact of system short-circuit current.

The degradation mechanism of GaN-based near-ultraviolet (NUV, 320–400 nm) light emitting diodes (LEDs) with low-indium content under electrical stress is studied from the aspect of defects. A decrease in the optical power and an increase in the leakage current are observed after electrical stress. The defect behaviors are characterized using deep level transient spectroscopy (DLTS) measurement under different filling pulse widths. After stress, the concentration of defects with the energy level of 0.47–0.56 eV increases, accompanied by decrease in the concentration of 0.72–0.84 eV defects. Combing the defect energy level with the increased yellow luminescence in photoluminescence spectra, the device degradation can be attributed to the activation of the gallium vacancy and oxygen related complex defect along dislocation, which was previously passivated with hydrogen. This study reveals the evolution process of defects under electrical stress and their spatial location, laying a foundation for manufacture of GaN-based NUV LEDs with high reliability.

Under the development goal of “Carbon Peak, Carbon Neutralization”, the concept of novel power system is proposed. Its representative features include AC/DC interconnection of power grid and large-scale access of new energy power stations. Under these characteristics, higher requirements are put forward for the short-circuit current breaking capacity of the circuit breaker. The DC component of short-circuit current and the injection of new energy into the system short-circuit current cannot be ignored. Based on the 330kV local power grid in Northwest China, this paper studies the power grid operation mode, DC component of short-circuit current and the influence of photovoltaic power station on short-circuit current. The influence law of DC component of short-circuit current on the actual breaking capacity of circuit breaker and access of photovoltaic power station on the short-circuit current are summarized. It can provide a theoretical basis for the selection of circuit breaker in novel power system.

In this paper, the cavitating flow in low specific speed axial flow waterjet pumps are treated at different cavitation conditions. In order to analyze the cavitating turbulent flow comprehensively, three axial flow waterjet pumps with the specific speed less than 650 min-1·m3s-1·m are chosen to compare the internal flow phenomenon. The investigations are conducted by numerical simulation, where RANS method is applied with k-ω SST turbulence model and homogeneous cavitation model. The results show that there are several types of cavitation such as tip leakage vortex cavitation, sheet cavitation attached on blade suction surface, and shedding cavity in the pumps. The vortex structure in the low specific speed waterjet pump contains tip leakage vortex, shedding vortex downstream of the sheet cavitation and perpendicular cavitation vortex. It is noted that the cavity firstly occurs at the leading edge near blade tip, and the sheet cavity covering the blade suction surface extends from leading edge to the middle part, while the tip leakage vortex cavitation develops with the decreasing cavitation number. Further analysis using relative vortex transport equation depicts that the vortex stretching term is the main contributor for the vorticity production in the pump, and the vortex dilation and baroclinic torque occur at the interface between cavity and water.

Multi-agent system is an important branch of distributed artificial intelligence. As a new field of engineering control science, it has developed vigorously in recent years. From a practical point of view, most existing agents, such as unmanned vehicles and unmanned aerial vehicles, are powered by mobile power supply. Therefore, it is of practical significance to consider the battery state and explore how to improve the overall battery life when designing the multi-agent control strategy. In this paper, we first introduced a classical algorithm based on the consensus theory, and on this basis, the overtaking action in the formation is realized by changing the topology, so as to simulate the individuals (action individuals) who consume more energy in the formation; then we discussed how to improve the endurance of high-energy-consuming individuals in formation through average energy consumption in strategy design, and proposed an algorithm based on energy-aware. Finally, the MATLAB simulation results show that compared with the classical algorithm, the proposed algorithm can improve the endurance of formation.

An Experimental Muon Source (EMuS) has been proposed to conduct muon spin rotation/relaxation/resonance (μSR) measurements at China Spallation Neutron Source (CSNS). To make better use of muons in each pulse, a highly segmented μSR spectrometer with more than 2000 detector channels is under design. Due to such high granularity of detectors, multiple counting events generated from particle scattering or spiral motion of positrons in a strong longitudinal field should be carefully considered in the design. According to the simulation, long scintillators have a good capability of angular discrimination. Detectors with cuboid geometries are better than those with frustum shapes. The cuboid detector with a length of 50 mm is longer enough to get the optimal range of discrimination angle. In a real μSR spectrometer, detectors can be placed parallelly along the beam direction or pointing to the sample. A figure of merit (FoM) has been proposed to compare such two arrangements by integrating their impacts on multiple counts and total counting loss in zero and longitudinal fields. The outstanding performance of multiple counting rejection due to the angular discrimination capability makes the pointing arrangement achieve much higher FoM. The simulation results can provide good support for the design of the highly segmented μSR spectrometer.

In order to solve the problem of reliable information transmission between data centers and data sources, between data sources and between data centers, as well as the "network island" communication problem, a dynamic MPLS VPN method is proposed, the principle and steps of the method are introduced, and how to apply the method to the supporting platform is explained in detail.

Monolayer transition metal dichalcogenides can normally exist in several structural polymorphs with distinct electrical, optical, and catalytic properties. Effective control of the relative stability and transformation of different phases in these materials is thus of critical importance for applications. Using density functional theory calculations, we investigate the effects of low-work-function metal substrates including Ti, Zr, and Hf on the structural, electronic, and catalytic properties of monolayer MoS2 and WS2. The results indicate that such substrates not only convert the energetically stable structure from the 1H phase to the 1T′/1T phase, but also significantly reduce the kinetic barriers of the phase transformation. Furthermore, our calculations also indicate that the 1T′ phase of MoS2 with Zr or Hf substrate is a potential catalyst for the hydrogen evolution reaction.

Stringer-skin debonding was one of the most important failure models in stiffened composite panels. In this paper, three-points bending tests were performed on representative stringer-skin structure of composite wing to simulate the flange-skin interface behavior and to obtain the failure mode and failure load. A 3D finite element model was built by using ABAQUS software to simulate interface failure with cohesive zone model. The numerical results agree well with test data, which validate the rationality of the finite element model. Hence the influence of factors during manufacture, installation and test in three-points bending tests, such as off-axis displacement, inclination loading and span, is studied. Results show that the initial debonding load and failure load of specimen decrease as the displacement from loading axis to central axis increases. The load of specimen decreases as the span increases. The influence of inclination loading is insignificant when the inclination angle is less than 6 degree. However, the initial debonding load and failure load of specimen decreases in varying degrees as the inclination loads increases. Furthermore, the initial debonding load decreases rapidly.

Most scanning schemes of multi-energy computed tomography (MECT) require multiple sets of full-scan measurements under different x-ray spectra, which limits the application of MECT with incomplete scan. To handle this problem, a flexible MECT scanning strategy is proposed in this paper, which divides one half scan into three curves. Also, a novel MECT reconstruction algorithm is developed to relax the requirement of data acquisition of MECT. For MECT, gradient images of CT images at different energies ideally share the same position of zero-value set (Pos-OS) for the same object. Based on this observation, the characteristics of limited-angle artifacts is first explored, and it is found that the limited-angle artifacts in the image domain are closely related to the angle trajectory of the scan. Inspired by this discovery, the Pos-OS of the gradient image from the fusion CT image is extracted, and it is incorporated as prior knowledge into the TV minimization model in the form of equality constraints. The alternating direction method is exploited to solve the improved optimization model iteratively. Based on this, the proposed algorithm is derived to eliminate the limited angle artifacts in the image domain.The experimental results show that the proposed method achieves higher reconstruction quality under the designed scanning configuration than other methods in the literature.

With the rapid development of automobile industry, ductile iron component has become one of the most important components, which is the core components in many aspects, such as engine crankshaft, wheel hub, etc., which will be subject to extremely complex loads. Therefore, the crankshaft R region is particularly prone to fatigue cracks, which requires us to continuously strengthen the internal defect detection technology. With the development of detection technology, conventional ultrasonic technology has been unable to meet the needs of society. Through electronic scanning and acoustic beam deflection focusing, we gradually improve the Ultrasonic phased array detection technology (hereinafter referred to as UPADT), which can better realize the detection of automobile ductile iron components. UPADT is a kind of ordered excitation to the beam element, which can realize the deflection and focusing of the sound beam [1]. By combining sector scanning, electron scanning and DDF, we can achieve more beam incident modes, which will have faster detection speed and more accurate sensitivity.

Aiming at the situation that the phase-functioned neural network can’t produce natural action or interact with the world poorly in some specific scenes, this paper proposes to divide different states according to the phase information of characters, and train several independent networks with different weights to predict the next frame state of characters. The experimental results show that, while the complexity of the model is reduced, the action generated by this method is more natural and fluent, which has good application value.

Parallel robots are small in size and high in accuracy, so they are widely used in processing and production industries. In order to give full play to the characteristics of high-speed motion of parallel robots, trajectory planning has become a hot spot in the industry. This paper proposes a trajectory planning algorithm based on NURBS. Firstly, the algorithm uses the characteristics of NURBS continuous and derivable to fit interpolation points, and then we obtain a smooth and continuous robot motion trajectory. Secondly, It uses interpolation algorithm to discretize the curve to get the robot motion sequence. Finally, It completes the entire motion process of the robot in three-dimensional space. Experiments show that the algorithm can be applied to the parallel robot control system, which can give full play to the performance of the parallel robot and ensure the stable and high-speed operation of the robot.

Based on the principle of flexible testing technology, the test software is designed hierarchically and modularized. By calling the optimization algorithm of the test process, the automatic combination of the test process and the package call of the basic unit program of the test, the optimal sequencing and flexible configuration of the valve group test process are realized, and the efficiency of the automatic test scheme of the valve group is effectively improved. The test results show that the optimized test scheme can reduce the test time by 14.8% ∼ 34.6% and the test energy consumption by 9.0% ∼ 11.2%.

We take the established inductively coupled plasma (ICP) wind tunnel as a research object to investigate the thermal protection system of re-entry vehicles. A 1.2-MW high power ICP wind tunnel is studied through numerical simulation and experimental validation. The distribution characteristics and interaction mechanism of the flow field and electromagnetic field of the ICP wind tunnel are investigated using the multi-field coupling method of flow, electromagnetic, chemical, and thermodynamic field. The accuracy of the numerical simulation is validated by comparing the experimental results with the simulation results. Thereafter, the wind tunnel pressure, air velocity, electron density, Joule heating rate, Lorentz force, and electric field intensity obtained using the simulation are analyzed and discussed. The results indicate that for the 1.2-MW ICP wind tunnel, the maximum values of temperature, pressure, electron number density, and other parameters are observed during coil heating. The influence of the radial Lorentz force on the momentum transfer is stronger than that of the axial Lorentz force. The electron number density at the central axis and the amplitude and position of the Joule heating rate are affected by the radial Lorentz force. Moreover, the plasma in the wind tunnel is constantly in the subsonic flow state, and a strong eddy flow is easily generated at the inlet of the wind tunnel.