Abstract: A liquid crystal composition containing a benzochromene compound and the use thereof in a liquid crystal display element or liquid crystal display. The liquid crystal composition comprises one or more compounds represented by Formula I and one or more compounds represented by Formula II. The liquid crystal composition has the characteristics of a small rotational viscosity, a large elastic constant, a high transmittance, a fast response speed, a strong resistance to ultraviolet light irradiation, and a high long-time light stability, and is particularly suitable for the field of TV display.

Abstract: A flat panel detector and a method performed by the flat panel detector are provided. A plurality of pixel units are arranged in an array, each pixel unit includes pixels arranged in a K×K sub-array, and each pixel is configured to provide a photoelectric signal. K is an odd number greater than 1. A gate driving circuit is configured to turn on the pixel units row by row under, so as to cause K rows of pixels in each turned-on pixel unit to generate photoelectric signals. A readout circuit is configured to read photoelectric signals from K columns of pixels in each column of pixel units, and generate image data for each pixel unit according to the photoelectric signals. A control circuit is connected to the gate driving circuit and the readout circuit.

Abstract: A method and system for predicting water flooding recovery of fault block reservoirs considering a whole process optimization includes: determining influencing factors in water flooding recovery of fault block reservoirs; screening master parameters of the water flooding recovery of the fault block reservoirs; determining a single-factor correlation between the water flooding recovery of the fault block reservoirs and the master parameters; designing multi-factor orthogonal experimental schemes; performing a whole-process water flooding optimization for each of the experimental schemes including separate-layer injection and production, well-type conversion, and injection and production adjustment, to obtain the maximum water flooding recovery; and determining a prediction model of the water flooding recovery of the fault block reservoirs using least square method based on results of the whole process optimization of orthogonal experiments, further obtaining a prediction model of the water flooding recovery of

Abstract: A method and system for predicting water flooding recovery of fault block reservoirs considering a whole process optimization includes: determining influencing factors in water flooding recovery of fault block reservoirs; screening master parameters of the water flooding recovery of the fault block reservoirs; determining a single-factor correlation between the water flooding recovery of the fault block reservoirs and the master parameters; designing multi-factor orthogonal experimental schemes; performing a whole-process water flooding optimization for each of the experimental schemes including separate-layer injection and production, well-type conversion, and injection and production adjustment, to obtain the maximum water flooding recovery; and determining a prediction model of the water flooding recovery of the fault block reservoirs using least square method based on results of the whole process optimization of orthogonal experiments, further obtaining a prediction model of the water flooding recovery of

Abstract: A bidirectional self-regulating chemical flooding method and system for enhancing oil recovery includes: determining the average particle size of dispersed phase droplets under stable seepage flow of an oil-in-water emulsion according to the average reservoir permeability; determining injection concentration of an emulsifier which matches a target reservoir according to reservoir seepage velocity; under a condition of keeping the injection concentration of the emulsifier constant, determining the optimal injection concentration of a polymer which matches the injection concentration of the emulsifier through core flooding experiments with the maximum equivalent ton oil accumulation as a target; determining total injection amount of the emulsifier and total injection amount of the polymer for implementing well group units; and optimizing injection amount of the emulsifier and the polymer in each single well by using a numerical simulator of a chemical flooding reservoir.

Abstract: The present invention discloses a multi-energy complementary system for a co-associated abandoned mine and a use method. The multi-energy complementary system for a co-associated abandoned mine includes a mining mechanism, a grouting mechanism and an energy mechanism. In the present invention, the mining of coal and uranium resources is realized through the mining mechanism, the subsidence and seepage reduction of the stratum is realized through the grouting mechanism, and the effective utilization of waste resources is realized through the energy mechanism. Finally, with the efficient cooperation of the three mechanisms, safe and efficient development and utilization of co-associated resources in the full life cycle are realized, and the purposes of green and efficient mining of coal and uranium resources and secondary development of a coal seam goaf are achieved, thereby facilitating the realization of dual-carbon goals and the development of low-carbon green energy.

Abstract: A method for encoding a three-dimensional audio signal is provided. The method includes: An encoder obtains a current frame of a three-dimensional audio signal; obtains coding efficiency of an initial virtual speaker for the current frame based on the current frame of the three-dimensional audio signal; and when the coding efficiency of the initial virtual speaker for the current frame meets a preset condition, determines an updated virtual speaker for the current frame from a set of candidate virtual speakers; encodes the current frame based on the updated virtual speaker for the current frame, to obtain a first bitstream; or when the coding efficiency of the initial virtual speaker for the current frame does not meet the preset condition, encodes the current frame based on the initial virtual speaker for the current frame, to obtain a second bitstream.

Abstract: A dynamic power control method and system for resisting multi-user parameter biased aggregation in federated learning are provided; the method includes: (1) establishing a federated learning system model for resisting parameter biased aggregation; (2) constructing a 5 corresponding objective function based on a training purpose of the federated learning system model; (3) introducing, according to the established federated learning system model, a power control factor for resisting user biased gradient aggregation, and determining a corresponding over-the-air computation communication model; (4) processing a signal by a receiver using an incoherent energy detection method without cooperation between the receiver and a transmitter; and (5) determining a federated learning security mechanism method based on resistance against parameter biased aggregation, and completing an updating training process of the federated learning system model.

Abstract: Embodiments of this application disclose a three-dimensional audio signal processing method and apparatus, to implement bit allocation of a signal. The method includes: performing spatial coding on a to-be-coded three-dimensional audio signal, to obtain a transmission channel signal and transmission channel attribute information, where the transmission channel signal includes at least one virtual speaker signal group and at least one residual signal group; and determining a bit allocation ratio of the virtual speaker signal group and a bit allocation ratio of the residual signal group based on the transmission channel attribute information.

Abstract: Embodiments of this application disclose a three-dimensional audio signal processing method and apparatus, to implement sound field classification of a three-dimensional audio signal, to accurately identify the three-dimensional audio signal. An embodiment of this application provides a three-dimensional audio signal processing method, including: performing linear decomposition on a current frame of a three-dimensional audio signal, to obtain a linear decomposition result; obtaining, based on the linear decomposition result, a sound field classification parameter corresponding to the current frame; and determining a sound field classification result of the current frame based on the sound field classification parameter.

Abstract: A non-invasive time domain reflection probe calibration method includes: using different volume ratio of ethanol and deionized water mixed solution to calculate a test target's medium weight coefficient and waveguide length of the non-invasive time domain reflection probes; using different concentrations of NaCl solutions to calibrate a waveguide geometric dimensioning of the non-invasive time domain reflection probes; preparing compacted soil samples with known different moisture contents and densities, and calibrating a correlation parameter of compacted soil samples' dielectric constant and conductivity with moisture content and density. The method not only determines the sensitivity of the test target medium of the non-invasive time domain reflection probes, but also obtains the waveguide length and geometric dimensioning of the probe, and realizes an accurate test of moisture content and density of the soil.

Abstract: Embodiments of the present disclosure provide a gimbal control method. The method includes receiving a first position and a second position wherein the first position and the second position are touched positions of an operation interface of a terminal; determining a rotation angle of the gimbal based on the first position, the second position, and an attitude of the gimbal at the first position; and controlling rotation of the gimbal based on the rotation angle.

Abstract: A three-dimensional audio signal coding method, apparatus, and encoder are described. The method includes, after obtaining a first correlation between a current frame of a three-dimensional audio signal and a representative virtual speaker set for a previous frame, the encoder determines whether the first correlation satisfies a reuse condition, where the first correlation is used to determine whether to reuse the representative virtual speaker set for the previous frame when the current frame is encoded. The method further encodes the current frame based on the representative virtual speaker set for the previous frame when the first correlation satisfies the reuse condition, to obtain a bitstream. A virtual speaker in the representative virtual speaker set for the previous frame is a virtual speaker used for encoding the previous frame of the three-dimensional audio signal.

Abstract: This application discloses a three-dimensional audio signal coding method and apparatus, and an encoder, and relates to the multimedia field. The method includes: After determining a first quantity of virtual speakers and a first quantity of vote values based on a current frame of a three-dimensional audio signal, a candidate virtual speaker set, and a voting round quantity, the encoder selects a second quantity of representative virtual speakers for the current frame from the first quantity of virtual speakers based on the first quantity of vote values, and further encodes the current frame based on the second quantity of representative virtual speakers for the current frame to obtain a bitstream. This achieves efficient data compression.

Abstract: This application discloses a three-dimensional audio signal coding method. After obtaining a fourth quantity of coefficients for a current frame of a three-dimensional audio signal and frequency domain feature values of the fourth quantity of coefficients, an encoder selects a third quantity of representative coefficients from the fourth quantity of coefficients based on the frequency domain feature values of the fourth quantity of coefficients, and selects a second quantity of representative virtual speakers for the current frame from a candidate virtual speaker set based on the third quantity of representative coefficients, and then encodes the current frame based on the second quantity of representative virtual speakers for the current frame to obtain a bitstream. The encoder selects the representative virtual speakers from the candidate virtual speaker set by using a small quantity of representative coefficients to represent all coefficients.

Abstract: A three-dimensional audio signal encoding method and apparatus, and an encoder are provided, and relate to the multimedia field. The method includes: The encoder obtains a first quantity of current-frame initial vote values for a current frame of a three-dimensional audio signal. Then, the encoder obtains, based on the first quantity of current-frame initial vote values and a sixth quantity of previous-frame final vote values, a seventh quantity of current-frame final vote values that are of a seventh quantity of virtual loudspeakers and that correspond to the current frame. Further, the encoder selects a second quantity of current-frame representative virtual loudspeakers from the seventh quantity of virtual loudspeakers based on the seventh quantity of current-frame final vote values. The encoder encodes the current frame based on the second quantity of current-frame representative virtual loudspeakers, to obtain a bitstream.

Abstract: An audio encoding method and apparatus and an audio decoding method and apparatus are disclosed. During encoding of an audio channel signal of a current frame, whether a first target virtual loudspeaker and a second target virtual loudspeaker corresponding to an audio channel signal of a previous frame of the current frame meet a specified condition is first determined. When the first target virtual loudspeaker and the second target virtual loudspeaker meet the specified condition, a first encoding parameter of the audio channel signal of the current frame is determined based on a second encoding parameter of the audio channel signal of the previous frame, so that the audio channel signal of the current frame is encoded based on the first encoding parameter to obtain an encoding result, and the encoding result is written into a bitstream.

Abstract: The present invention discloses a sand control device for marine hydrate production, which comprises a top motor, a bottom motor, and an inner-layer sand control cylinder, an outer-layer sand control cylinder and an outer-layer sand control screen coaxially arranged from inside to outside, wherein the top motor and bottom motor are configured to control the inner-layer sand control cylinder and the outer-layer sand control cylinder to rotate reversely, and wherein a plurality of sand retaining balls are provided between the inner-layer sand control cylinder and the outer-layer sand control cylinder and between the outer-layer sand control cylinder and the outer-layer sand control screen. According to the present invention, the arrangement of the inner-layer sand control cylinder and the outer-layer sand control cylinder rotating reversely can effectively prevent formation sand from accumulating on the surface of a sand control screen pipe and blocking the sand control screen pipe.

Abstract: Provided is a display method for A-pillar-mounted display assemblies of a vehicle. The method includes: acquiring facial posture information of a driver of the vehicle in a camera coordinate system by any one driver monitoring assembly of at least one driver monitoring assembly, determining a visual field of the driver based on a gaze direction of the driver and the eye position of the driver, acquiring coordinates of the two display assemblies in a world coordinate system, converting the coordinates of the two display assemblies in the world coordinate system into coordinates in the camera coordinate system based on a first conversion relationship, determining whether any one display assembly of the two display assemblies is within the visual field, and capturing an external image of the vehicle captured by the imaging assembly.

Abstract: A video shooting method device and system is provided. The method includes: determining a category of an object, and determining a target lens motion mode for shooting a video of the object based on the category of the object, so as to shoot the video of the object with the target lens motion mode. This method may reduce the requirements on the user's video shooting skills and facilitate video shooting.