Abstract: A riding mowing device includes a frame; a cutting assembly; a traveling assembly configured to drive the riding mowing device to travel and including a first traveling assembly located on the front part of the riding mowing device and a second traveling assembly located on the rear part of the riding mowing device, where the first traveling assembly and the second traveling assembly are separately mounted on the frame; and a power supply assembly configured to supply power to at least the cutting assembly and the traveling assembly and mounted to the frame. The riding mowing device further includes one of a steering wheel assembly and an operating lever assembly, and one of the steering wheel assembly and the operating lever assembly is selectively mounted on the frame.

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 photosensitive assembly includes a circuit board. The circuit board has a first surface, a second surface opposite to the first surface, and a first through hole extending through the first surface and the second surface. A photosensitive chip is disposed on the second surface. The photosensitive chip has a photosensitive area and a non-photosensitive area connected to the photosensitive area, the non-photosensitive area is electrically connected to one side of the second surface, and the photosensitive area is exposed from the first through hole. A reinforcing plate is disposed on the first surface. A thermal conductive layer is disposed on the photosensitive chip, and the thermal conductive layer includes a silica gel or a metal.

Abstract: A photography stand includes a central pipe and a supporting frame. The top of the central pipe is configured to mount photographic equipment. The supporting frame is connected to the central pipe, and provided adjacent to the bottom of the central pipe. The supporting frame moves relative to the central pipe along the axial direction of the central pipe. The supporting frame is unfolded when moving along the axial direction of the central pipe toward the bottom of the central pipe by a preset distance and then moving continuously toward the bottom of the central pipe. The supporting frame is folded when moving along the axial direction of the central pipe toward the top of the central pipe. According to the photography stand, the supporting frame is unfolded automatically after moving along the axial direction of the central pipe toward the bottom of the central pipe by the preset distance.

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: 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: Disclosed are an information processing method and a terminal device. The method comprises: acquiring first information, wherein the first information is information to be processed by a terminal device; calling an operation instruction in a calculation apparatus to calculate the first information so as to obtain second information; and outputting the second information. By means of the examples in the present disclosure, a calculation apparatus of a terminal device can be used to call an operation instruction to process first information, so as to output second information of a target desired by a user, thereby improving the information processing efficiency. The present technical solution has advantages of a fast computation speed and high efficiency.

Abstract: Disclosed is a high ultraviolet blocking polylactic acid composite material reinforced by POSS modified bamboo powder. The preparation method therefor includes steps of carrying out chemical grafting modification of bamboo powder with proper particle size by using POSS containing specific organic groups, and then adding the modified bamboo powder to polylactic acid for melting and co-extrusion to obtain POSS modified bamboo powder. The present disclosure makes full use of the 30% lignin in the bamboo powder, having the advantages of wide source, biological metabolizability and low price; the present disclosure does not need the traditional inorganic ultraviolet blocking agent, nor need to extract refined lignin from natural materials, but directly takes inexpensive and easy-to-obtain bamboo powder as main raw material. The composite material prepared in the present disclosure can greatly improve the UV blocking performance, mechanical properties and thermal stability of the PLA.

Abstract: An online concierge system provides arrival prediction services for a user placing an order to be retrieved by a shopper. An order may have a predicted arrival time predicted by a model that may err under some conditions. To reduce the likelihood of providing the predicted arrival time (and related services) when the arrival time may be incorrect, the prediction model and related services are throttled (e.g., selectively provided) based on one or more predicted delivery metrics, which may include a time to accept the order by a shopper and a predicted portion of late orders that will be delivered past the respective predicted arrival times. The predicted delivery metrics are compared with thresholds and the result of the comparison used to selectively provide, or not provide, the predicted delivery services.

Abstract: Disclosed is a high ultraviolet blocking polylactic acid composite material reinforced by POSS modified bamboo powder. The preparation method therefor includes steps of carrying out chemical grafting modification of bamboo powder with proper particle size by using POSS containing specific organic groups, and then adding the modified bamboo powder to polylactic acid for melting and co-extrusion to obtain POSS modified bamboo powder. The present disclosure makes full use of the 30% lignin in the bamboo powder, having the advantages of wide source, biological metabolizability and low price; the present disclosure does not need the traditional inorganic ultraviolet blocking agent, nor need to extract refined lignin from natural materials, but directly takes inexpensive and easy-to-obtain bamboo powder as main raw material. The composite material prepared in the present disclosure can greatly improve the UV blocking performance, mechanical properties and thermal stability of the PLA.

Abstract: Provided is a steam jet multifunctional aircraft deicing vehicle with steam jet, includes a vehicle body, where a steam generating assembly is arranged in the vehicle body, and the steam generating assembly is connected with a steam conveying assembly. A moving assembly is rotatably connected above the vehicle body, and the moving assembly is rotatably connected with an execution assembly. The execution assembly includes a first spray head assembly and a second spray head assembly. The steam conveying assembly includes a first supercharger and a second supercharger arranged side by side, where an air outlet end of the first supercharger is communicated with one end of a first air outlet pipe, and an other end of the first air outlet pipe is communicated with spray heads of the second spray head assembly through a first air pipeline.

Abstract: A voice coil motor held immobile by magnetic attraction when not in use for photography purposes includes a base, a magnet fixed thereto, a carrier, a magnetic member, and a coil. The magnetic member is fixed to the carrier and is attracted by a permanent magnetic field (first MF) of the magnet on the base. The coil is fixed to the carrier and the magnetic member. When the voice coil motor is powered on, the coil generates a second magnetic field (second MF) opposing the first MF. The second MF reduces or eliminates the attractive force of the first MF of the magnet, to separate the carrier and its fittings and allow them to work freely. A lens module and an electronic device are further provided.

Abstract: The present disclosure provides a method for identifying modal parameters of engineering structures based on fast stochastic subspace identification, and relates to the field of structural modal parameters identification. The method includes the following steps: collecting responses; obtaining a unitary matrix by performing random projection on and QR decomposition of a matrix; obtaining a small matrix by projecting a Toeplitz matrix onto the unitary matrix; obtaining U, S, V matrices respectively by performing singular value decomposition of the small matrix; performing eigenvalue decomposition; and determining an order interval. According to the present disclosure, the small matrix is obtained through performing random projection on and QR decomposition of the traditional Toeplitz matrix, the dimensionality of the matrix by singular value decomposition is reduced and the computational efficiency of the matrix is improved.

Abstract: A method and device for intra prediction are provided. The method includes: when determining that a current level obtained by partitioning an input point cloud is lower than a target level, obtaining occupation information of a first number of neighbouring nodes of a current node; extracting occupation information of a second number of neighbouring nodes from the occupation information of the first number of neighbouring nodes, the first number being greater than the second number, and the second number of neighbouring nodes being in an association relationship with a child node of the current node, and performing intra prediction on occupation information of the child node of the current node based on the occupation information of the second number of neighbouring nodes to obtain a first prediction result.

Abstract: The present disclosure provides a method for fabricating a self-supporting gallium nitride substrate, comprising: 1) providing a composite substrate including a sapphire substrate and a gallium nitride film; 2) forming a temporary bonding layer on the gallium nitride film; 3) bonding a transfer substrate to the composite substrate by means of the temporary bonding layer; 4) stripping the sapphire substrate by means of a laser stripping process; 5) performing weak bonding on a receiving substrate and the gallium nitride film, and detaching the transfer substrate from the gallium nitride film by invalidating the temporary bonding layer, and 6) epitaxially growing a gallium nitride epitaxial layer on the gallium nitride film, and invalidating the weak bonding by means of the lattice mismatch stress and/or the thermal mismatch stress between the gallium nitride film and the gallium nitride epitaxial layer and the receiving substrate, so as to realize separation between the gallium nitride film and the receiving s

Abstract: An electrical machine with a rotor coupled to a drive shaft of an engine; a DC electrical network; a power electronics converter connected, on a DC-side, to the DC electrical network, and, on an AC-side, to the electrical machine, the power electronics converter comprising a plurality of transistors and associated diodes connected in anti-parallel with the transistors; and a controller configured to control switching of the transistors so that the converter either inverts DC power to AC power or rectifies AC power to DC power. The controller is further configured, responsive to a determination that there is a fault in the DC electrical network, to operate in a fault mode in which the controller controls the switching of the transistors so that a fault current is shared between the transistors and the associated diodes.

Abstract: A current detection apparatus includes a first transformation unit, a power supply unit, a current detection unit, and a processing unit. A detected cable passes through a hollow part of the first transformation unit. The power supply unit is connected to the first transformation unit. The current detection unit is connected to the first transformation unit. The processing unit calculates a current value on the detected cable.

Abstract: This application provides a method for controlling a virtual object in a virtual scene performed by an electronic device. The method includes: presenting, in the virtual scene, a first virtual object and at least one second virtual object that is in an action execution state of a target performance, wherein the action execution state of the target performance indicates that the second virtual object performs an action of the target performance in the virtual scene; in response to a movement control instruction for the first virtual object, controlling the first virtual object to move in the virtual scene; and during movement of the first virtual object, when a position of the first virtual object meets an execution condition of the target performance, controlling the first virtual object to automatically perform the action of the target performance.

Abstract: The present disclosure provides a design method for an active disturbance rejection roll controller of a vehicle under disturbance of complex sea conditions, including: step 1: establishing a vehicle roll attitude control model; step 2: designing an active disturbance rejection controller (ADRC) on the basis of the control model in step 1 and a pole placement method; and step 3: performing an active disturbance rejection roll control by using the active disturbance rejection controller in step 2. The present disclosure solves the problem of a stable control of the vehicle under the disturbance of the complex sea conditions.