Abstract: The disclosure provides a method and an apparatus for predicting flight delay, a device and a storage medium. The method includes: acquiring flight historical data, where the flight historical data includes take-off amount and delay amount of flights during each of a plurality of time periods; determining prior knowledge of each of the plurality of time periods according to the take-off amount and the delay amount of the flights during each of the plurality of time periods; constructing a SVM prediction model according to the prior knowledge and a standard SVM model; and predicting a flight delay situation according to the SVM prediction model. The prediction of the flight delay situation for each of the plurality of time periods is realized.

Abstract: The invention discloses a system for hole making for an aircraft skin by normal positioning and locking. The hole-making system includes a posture adjustment part, a normal positioning and locking part and a hole-making execution part. This system solves the problems that the device in the prior art has high complexity and cumbersome positioning and does not adapt to complex curved surfaces, thereby failing to satisfy the needs of efficient hole making in different space states. In the present invention, the expansion of an outer expansion sleeve in a bottom sleeve locks a normal direction for hole making, thereby ensuring the positioning accuracy of the normal direction. An axial position is locked by the mutual cooperation of an axial positioning groove of the bottom sleeve and an axial positioning rib of the outer expansion sleeve. A hole-making auxiliary cylinder contracts to counteract part of an axial force for hole making.

Abstract: The present disclosure relates to the technical field of aerodynamic and acoustic measurement, in particular to a comprehensive performance test platform for acoustic liner. Based on this comprehensive performance test platform for acoustic liner, the stress of the measured acoustic liner under high sound intensity can be measured by using strain gauges arranged on the measured acoustic liner, the aerodynamic drag of the measured acoustic liner can be measured by using the drag balance, and the acoustic performance parameters of the measured acoustic liner can be calculated based on the sound pressure data obtained by the microphone array. With this test platform, the stress, the aerodynamic drag and the acoustic performance parameters of the measured acoustic liner can be measured simultaneously, which overcomes the problem of inaccurate experimental data obtained in inconsistent experimental conditions caused by conventional separate acoustic liner tests.

Abstract: The disclosure provides a dynamic recovery method and system for UAVs and storage medium. On the basis of obtaining the environmental information of UAVs, combined with different factors such as the following task quantity of each UAV, the distance from the current position of each UAV to the recovery point, current performance of each UAV, total cost function is constructed, and optimization is carried out through improved particle swarm optimization algorithm. Then on the premise of the lowest recovery cost, the priority of each UAV is obtained. For the ordered UAV, the route to the recovery point is determined. At the same time, it is necessary to consider conflict resolution of UAVs when encountering obstacles in the flight process, as well as the possible failure in line recovery. At this time, it is necessary to reorder some hovering UAVs to ensure flight safety of UAVs and robustness of the algorithm.

Abstract: A magnetically suspended control moment gyroscope comprising: a gimbal; a flywheel system, set in the gimbal; wherein the flywheel system comprises: a housing; a shaft, arranged in an inner cavity of the housing; a radial magnetic bearing, comprising: a first rotor portion and a first stator portion fixed to the shaft; an upper axial magnetic bearing and a lower axial magnetic bearing, wherein the upper axial magnetic bearing is fixed to an upper end of the first stator portion, the lower axial magnetic bearing is fixed to a lower end of the first stator portion; a wheel body, set in the radial magnetic bearing, fixed to the first rotor portion; an upper axial thrust plate and a lower axial thrust plate, wherein the upper axial thrust plate is fixed to an upper end of the wheel body, and is on an upper end of the upper axial magnetic bearing, the lower axial thrust plate is fixed to a lower end of the wheel body, and is under a lower end of the lower axial magnetic bearing.

Abstract: The embodiments of this disclosure disclose an image object detection method, device, electronic equipment, and computer-readable medium. A specific mode of carrying out the method includes: performing region segmentation on a target image to obtain at least one image region; performing feature extraction on each image region in the at least one image region to obtain at least one feature map; generating a semantic relation graph and a spatial distribution relation graph based on the at least one feature map and the at least one image region; generating an image region relation graph based on the semantic relation graph and spatial distribution relation graph; determining a target image region from the at least one image region based on the image region relation graph; displaying the target image region. This implementation mode achieves an improvement of user experience and a growth of network traffic.

Abstract: The present disclosure provides a device for separating sub-micron particles in the air, comprising a first separation channel, a second separation channel and a collection device which are connected in sequence, wherein each of the first separation channel and the second separation channel is of a rectangle structure with two open ends, the height H1 of the first separation channel is greater than the height H2 of the second separation channel, and each separation channel is provided with a vibration sound source and an antimicrobial coating layer. Based on the agglomeration theory of suspended particles in the air by ultrasonic standing waves, the device can aggregate sub-micron suspended particles flowing into each channel of the device on the upper and lower wall surfaces and the centerline of the channel, and sterilize the aggregated particles, thereby effectively removing the sub-micron suspended particles in the air.

Abstract: A sector situation (SS) evaluation framework is based on knowledge transfer and is specifically applicable for small-training-sample environment. The SS evaluation framework is able to effectively mine knowledge hidden within the samples of both target and non-target sectors, and properly handle the integration between the knowledge derived from different sectors. This framework includes three main steps: (1) sufficiently mine the knowledge within the samples of the target sector using the strategies of multi-factor subset generation and multi-base evaluator construction, and build target base evaluators; (2) precisely learn the knowledge in the samples of the non-target sectors using similar strategies for the target sector, together with a sample transformation, and build non-target base evaluators; and (3) efficiently integrate the target and non-target base evaluators based on evaluation confidence analysis of those base evaluators.

Abstract: A meshless method for solid mechanics simulation, which includes the following steps: first constructing a trial function and a test function by distributing points according to a geometric shape of a structure; then introducing numerical flux to correct the traditional Galerkin weak form; and finally substituting the trial and test functions into the weak form to construct a global stiffness matrix of the structure and a system of algebraic equations, and solving the system of algebraic equations to obtain displacement and stress of each point, thus completing simulation and analysis of the structure deformation and stress.

Abstract: A bionic visual navigation control system for autonomous aerial refueling docking includes: a tanker/receiver bottom layer control module, a multi-wind disturbances hose-drogue stable control module, an enable and select module, a close-range bionic vision relative navigation module, and a receiver relative position precise control module. A bionic visual navigation control method for autonomous aerial refueling docking is also provided. The present invention aims at improving the reliability, anti-interference and accuracy of the close-range relative navigation in the autonomous air refueling docking stage, and designs a matching relative position accurate control method with control switch, thereby improving the accuracy of close-range navigation and control, thereby promoting the successful realization of probe-and-drogue autonomous aerial refueling and improving the autonomy of UAVs.

Abstract: A method for anticipating the tipping point of traffic resilience based on percolation analysis, includes steps of: step (I) based on the topology structure of the urban road network and daily traffic operation data, constructing the urban traffic dynamical network; step (II): based on the urban traffic dynamical network constructed, analyzing the relationship between the system performance of urban traffic functional network and the congestion rate by percolation analysis; and step (III): based on the relationship between the system performance and the congestion rate, exploring the resilience function of the urban traffic functional network, and analyzing its resilience pattern and its resilience tipping point.

Abstract: The present disclosure provides a self-regulating electric heating film, including: an insulating isolation layer, an interdigital electrode arranged on the surface of the insulating isolation layer, a positive temperature coefficient coating covering the surface of a secondary electrode of the interdigital electrode, and an insulating protective layer covering the surface of a primary electrode of the interdigital electrode, wherein the positive temperature coefficient coating is not in contact with the primary electrode of the interdigital electrode, and the insulating protective layer overlaps the positive temperature coefficient coating.

Abstract: The present invention relates to the technical field of flexible drag reduction coatings, and in particular to a method for preparing a flexible and elastic drag reduction film. The flexible and elastic drag reduction film prepared by the present invention has excellent flexibility and elasticity. The film has a groove structure on a surface, and is suitable for curved surfaces and pipe surfaces of different diameters. The film is directly used without the need for an adhesive. It is sheathed on curved structures or devices of different diameters and curvatures by virtue of its own flexibility and elasticity, reducing an error due to the film adhesion.

Abstract: A target detection method based on the fusion of prior positioning of a millimeter-wave radar and a visual feature includes: simultaneously obtaining, based on the millimeter-wave radar and a vehicle-mounted camera after being calibrated, point cloud data of the millimeter-wave radar and a camera image; performing spatial 3D coordinate transformation on the point cloud data to project transformed point cloud data onto a camera plane; generating a plurality of anchor samples based on projected point cloud data according to a preset anchor strategy, and obtaining a final anchor sample based on a velocity-distance weight of each candidate region; fusing RGB information of the camera image and intensity information of an RCS in the point cloud data to obtain a feature of the final sample; and inputting the feature of the final anchor sample into a detection network to generate category and position information of a target in a scenario.

Abstract: The present invention discloses a method for reconstructing incomplete data of X-ray absorption contrast computed tomography (CT) based on deep learning (DL). The method includes the following steps: using a filtered back projection (FBP) algorithm to obtain an initial reconstructed image; forward projecting the initial reconstructed image to obtain artifact-contaminated complete projection sequences; using a DL technique to process the artifact-contaminated projection sequences to obtain artifact-free projection sequences; using the FBP algorithm to reconstruct the artifact-free projection sequences to obtain a final reconstructed image. Compared with the traditional incomplete data reconstruction methods, the examples of the present invention feature a simpler calculation process, fewer parameters to be manually set, a faster calculation speed and higher image quality.

Abstract: A target detection method based on the fusion of prior positioning of a millimeter-wave radar and a visual feature includes: simultaneously obtaining, based on the millimeter-wave radar and a vehicle-mounted camera after being calibrated, point cloud data of the millimeter-wave radar and a camera image; performing spatial 3D coordinate transformation on the point cloud data to project transformed point cloud data onto a camera plane; generating a plurality of anchor samples based on projected point cloud data according to a preset anchor strategy, and obtaining a final anchor sample based on a velocity-distance weight of each candidate region; fusing RGB information of the camera image and intensity information of an RCS in the point cloud data to obtain a feature of the final sample; and inputting the feature of the final anchor sample into a detection network to generate category and position information of a target in a scenario.

Abstract: This disclosure provides a method and an apparatus for monitoring a working state, which automatically collect an image of a staff in real time, determines point of gaze information of the staff based on the image of the staff thus collected, and further determines the working state of the staff according to the point of gaze information. Since the whole process does not require the participation of the staff, the normal work of the staff is not disturbed. Moreover, the accuracy in the monitoring of the working state is improved by avoiding influence of the subjective factors on the assessment result if staff participation is involved.

Abstract: A construction method of a test case constraint control technology based on epigenetics includes steps of: 1: defining a fitness function, a genetic coding method, and a constraint control rule; 2: initializing parameters: setting a population size, an evolution number, and a termination fitness function value; 3: initializing a population: randomly generating an initial population; 4: performing evolution termination judgment; 5. performing constraint regulation based on the epigenetics: performing constraint methylation and constraint acetylation according to the constraint control rule; 6: selecting individuals; 7: completing epigenetic evolution of the population; and 8: outputting a test case set; wherein through the above steps, construction of an epigenetic test case constraint control technology is completed, so as to design test cases that are more in line with the actual operation conditions of the software, find more potential software failures, and improve the quality of software testing.

Abstract: A zero-stiffness impact isolation device includes a shell, a half-hourglass-shaped boss, a sliding block, a spring, a motion guide assembly, and an inner core. Where the motion guide assembly includes a linear bearing fixed to the shell and the inner core and a corresponding sliding rod, and is divided into a transverse guide assembly and a longitudinal guide assembly. The spring is sleeved outside the sliding rod of the transverse motion guide assembly, and two ends of the spring are in contact with the sliding block and the inner core, respectively. When the device suffers from external impact load, the inner core and the separated object carry out a reciprocating motion, the sliding block is extruded by the half-hourglass-shaped boss to move side to side with respect to the inner core, and the spring provides elastic force to the sliding block in the process.

Abstract: Provided are a method and device for determining a motion trajectory of a target. The method includes: acquiring a transmitted signal, a first echo signal, and a second echo signal of a frequency modulated continuous wave radar; performing a coherent operation on the transmitted signal and the first echo signal, to determine a beat signal therebetween; performing a two-dimensional fast Fourier transform on the beat signal to determine an initial position of the target; performing a short-time Fourier transform on the beat signal to determine a radial velocity of the target; calculating a difference frequency signal between the first and second echo signals; determining a tangential velocity of the target according to the difference frequency signal; inputting the initial position, the radial velocity, and the tangential velocity to a Kalman filter, and receiving a motion trajectory of the target output by the Kalman filter.