401 results about "Quadrilateral" patented technology

The invention discloses a hybrid Lp regularization magnetotelluric two-dimensional inversion method based on adaptive weight, and the method comprises the steps: reading magnetotelluric observation data, carrying out the quadrilateral finite element grid discretization of a whole inversion region, building an inversion grid, and building an initial model and a prior model of the inversion conductivity of the inversion region; based on the initial model and the prior model of the inversion conductivity and the magnetotelluric observation data, constructing a mixed Lp regularization inversion objective function comprising an L1 regularization item, an L2 regularization item and a data fitting item; in an inversion iteration process, adaptively adjusting weight factors of the L2 regularization item and the L1 regularization item; and based on the inversion grid, performing magnetotelluric two-dimensional inversion according to the inversion objective function mixed with Lp regularization, the initial model and magnetotelluric observation data, and outputting optimal model parameters of Gaussian Newton inversion to obtain underground electrical structure information. According to the invention, the resolution and accuracy of the inversion result are improved.

A method for identifying and calculating the volume of over- and under-excavation in tunnels based on laser point clouds belongs to the field of intelligent tunnel construction and blasting quality assessment technology. Technical solution: The scanned point cloud data is denoised; a design contour point cloud is generated and aligned with the centerline of the actual excavated tunnel; the actual collected tunnel excavation point cloud and the design contour point cloud are Delaunay tetrahedralized; the actual tunnel point cloud is traversed, and the vector dot product formed between the point cloud and the triangular sides of the convex hull is calculated; over- and under-excavation areas are identified; a polyhedron is constructed from the design contour point cloud and the actual excavated area point cloud constituting the area; the polyhedron is divided into quadrilaterals, and the volume of each quadrilateral is calculated, thereby calculating the volume of each over- and under-excavation area. Beneficial effects: This invention can quickly measure over- and under-excavation areas and quantities that are difficult to calculate in tunnel blasting quality assessment, and can replace cumbersome and time-consuming total station and manual measurement methods; this method has the advantages of high precision, high efficiency, and high flexibility.

The invention discloses a grid generation method and device for finite element analysis of an aircraft airfoil quadrilateral structure, equipment and a medium, and relates to the technical field of multi-physics field coupling numerical simulation. Curve distances between discrete grid points and upper airfoil surface trailing edge points of an airfoil are calculated; the method comprises the following steps: initially segmenting an airfoil profile grid to obtain quadrilateral regions, calculating first control angular points at a front edge and a rear edge corresponding to an upper airfoil surface and a lower airfoil surface, second control angular points in an airfoil profile, first grid edges around an airfoil profile, intersecting edges at the front edge and the rear edge, and second grid edges in the airfoil profile, and constructing a computational domain grid; repeated grid point deletion, grid point list updating and grid unit list updating are carried out on the computational domain grid; and according to the target grid point list and the target grid unit list, generating a grid for finite element analysis of the quadrilateral structure of the aircraft airfoil, so that the full quadrangle of the grid units and the consistency of the grid units among different airfoil profiles can be ensured.

Disclosed are lattice materials including a truss structure obtained by arranging struts to form at least two triangles on each side of a polygon (i.e., a triangle, a quadrilateral, or a hexagon), which are used in many engineering fields, especially in materials engineering. The elastic modulus values per unit weight of many of the lattice materials produced from the truss structure are higher than those of the most existing cellular solids with stochastic cell distributions and many existing lattice materials. Using the truss structure disclosed herein, it is possible to produce two-dimensional (planar) lattice materials as well as spherical or tubular lattice structures in the form of a first cylindrical tube or a second cylindrical tube.

The invention discloses a distributed urban and rural planning decision support method and system, and relates to the technical field of data analysis, and the method comprises the following steps: S100, drawing a planar graph of a to-be-planned region, dividing the planar graph of the region according to a Morse decomposition method, and constructing a region matrix, S200, calculating the coverage rate of the region matrix, and S300, calculating the coverage rate of the region matrix. And planning the surveying and mapping path. According to the method, planning units and surveying and mapping grids are unified into the same quadrilateral matrix through Morse complex, repeated zoning and edge matching errors are effectively avoided, the edge weight is inversely proportional to the building coverage rate, an unmanned aerial vehicle and a surveying and mapping vehicle automatically and preferentially encrypt a high built-up area, field working hours are saved, the data precision of a core construction area is guaranteed, and the construction efficiency is improved. The regional matrix naturally corresponds to edge nodes, and each node only communicates with an adjacent unit, so that the MST and the local route can be locally solved, the communication complexity is reduced, and the method is suitable for large-scale regional surveying and mapping.

The invention provides a negative poisson ratio tension metamaterial structure and application thereof in impact resistance of an unmanned aerial vehicle. The negative Poisson's ratio stretch-draw metamaterial structure is composed of a plurality of two-dimensional D-bar stretch-draw integral structures. The two-dimensional D-bar stretch-draw integral structure is composed of a plurality of two-dimensional D-bar stretch-draw unit structures. The two-dimensional D-bar tensioning unit structure is composed of four same rod pieces, four rigid hinges and two same elastic ropes. Wherein every two of four rod pieces of the two-dimensional D-bar tensioning unit structure are connected through a rigid hinge to form a quadrilateral structure, and the four rigid hinges are diagonally connected and fixed through two elastic ropes; and two elastic ropes are adopted for fixing. Compared with other stretch-draw metamaterial structures, the stretch-draw metamaterial based on the two-dimensional D-bar has the advantages that the negative Poisson's ratio structure can be utilized to show better energy absorption characteristics, and when the unmanned aerial vehicle collides or falls off, impact force can be effectively dispersed, and damage to an aircraft body is reduced.

Various aspects of a dimple pattern methodology, and dimple pattern configurations are disclosed herein. A spherical quadrilateral segment division can be used to maintain a high level of symmetry in the dimple pattern while also maintaining a specific dimple layout in polar regions of the golf ball. In one aspect, the specific configurations disclosed herein can provide geometric symmetry while being adaptable to relatively complex processes for forming golf ball covers. Furthermore, the configurations disclosed herein provide a dimple pattern with a high level of symmetry having a particular subset of preferred polar dimples.

The invention belongs to the technical field of engineering surveying, and particularly discloses a river-crossing leveling method and system.The method comprises the steps that four control points are arranged on the two sides of a water area to be measured, each control point is provided with a centering rod tool, and each centering rod tool is integrated with an upper-layer prism and a lower-layer prism with the preset fixed vertical distance; a first total station and a second total station are erected on the two banks of the water area, upper-layer prisms and lower-layer prisms arranged on centering rod tools on the opposite banks are observed synchronously and oppositely, and vertical angle and slant distance data of all observation targets are obtained; and based on the vertical angle and slope distance data, a preset fixed vertical distance is used as a checking condition, and the height difference between the target positions on the two banks is solved. According to the method, the double-layer prism tool is introduced into a physical forced closing check condition, and traditional quadrilateral geometric closing check is combined, so that the data redundancy and the reliability of results are greatly enhanced, and system errors can be effectively identified and separated.

Various aspects of a dimple pattern methodology, and dimple pattern configurations are disclosed herein. A spherical quadrilateral segment division can be used to maintain a high level of symmetry in the dimple pattern while also maintaining a specific dimple layout in polar regions of the golf ball. In one aspect, the specific configurations disclosed herein can provide geometric symmetry while being adaptable to relatively complex processes for forming golf ball covers. Furthermore, the configurations disclosed herein provide a dimple pattern with a high level of symmetry having a particular subset of preferred polar dimples.

This invention provides a rotation-aware enhanced variable window attention super-resolution method, belonging to the field of image processing technology. It includes acquiring and preprocessing the original remote sensing image of the target object, segmenting it into several basic windows, extracting feature vectors, using quadrilaterals to predict the basic parameters of the projective transformation matrix based on the extracted feature vectors to obtain the reconstructed projective transformation matrix, extracting the rotation angle difference between any two quadrilaterals as a rotation-aware term, establishing a variable window attention mechanism, embedding the variable window attention mechanism into a SwinIR network to build a high-precision super-resolution model architecture, training the high-precision super-resolution model, inputting real-time remote sensing images into the high-precision super-resolution model, and outputting a high-resolution image containing the target sampling area. By combining the variable window attention mechanism with the rotation-aware mechanism, the super-resolution reconstruction accuracy and geometric consistency of rotated objects are significantly improved while maintaining computational efficiency.

Golf balls having dimple patterns arranged in dipyramid layouts are disclosed. The patterns may be arranged in triangular dipyramid, quadrilateral dipyramid, pentagonal dipyramid, or hexagonal dipyramid layouts. The dipyramid patterns have six, eight, ten, or twelve substantially identical dimple sections, where each dimple section is defined by a spherical triangle. The dimples in each of the identical dimple sections have at least two different dimple diameters including a minimum dimple diameter and a maximum dimple diameter. The resulting dimple patterns have a surface coverage of about 70 percent or less. The reduced surface coverage helps to reduce the flight of the golf balls.

The invention belongs to the technical field of aircraft thin-wall structure design, and particularly relates to a method for correcting a quadrilateral shell unit in aircraft thin-wall structure finite element analysis, which comprises the following steps of: 1, establishing a unit coordinate system for the quadrilateral shell unit; step 2, under the unit coordinate system, establishing an equilibrium equation of a plane stress unit related to in-plane deformation, and calculating a rigidity matrix of the plane stress unit; step 3, under the unit coordinate system, establishing a balance equation of a bending plate unit related to out-of-plane deformation, and calculating a rigidity matrix of the bending plate unit; 4, applying an in-plane rotation penalty term on the rotational stiffness of the quadrilateral shell unit, and calculating the influence of the in-plane rotation penalty term on the strain energy function of the quadrilateral shell unit under the unit coordinate system to obtain an in-plane rotation stiffness matrix; 5, calculating a stiffness matrix of the quadrilateral shell unit under the unit coordinate system; and step 6, coordinate transformation is carried out to obtain a stiffness matrix of the quadrilateral shell unit under the overall coordinate system.

The present invention discloses a robust optimization method for autonomous optical navigation landmarks for planetary landing, which belongs to the field of deep space exploration technology. The implementation method of the present invention is as follows: using the height information of the lander to determine the scale of the image plane projected onto the planetary surface, and deriving the quadrilateral vertex expression of the field of view based on the geometric relationship; using the relationship between the field of view vertex deviation and the lander posture error, converting the posture uncertainty to the field of view vertex uncertainty, and using the error ellipse to describe the field of view vertex uncertainty distribution; screening the quadrilateral area formed by the intersection of common tangents, which is the field of view intersection under the lander posture uncertainty; using the nominal trajectory and camera parameters to estimate the field of view sequence, combining the field of view intersection acquisition method to obtain the field of view intersection sequence, the field of view intersection sequence is obtained by offline estimation, and the amount of onboard calculation of the lander is reduced; using the observability of the navigation system to establish the landmark optimization index, optimize the selection of the landmarks in the field of view intersection sequence, and reduce the influence of posture uncertainty on the selected landmarks.

The invention discloses a method for optimizing manufacturability of a welding topological optimization structure, which belongs to the technical field of computer aided design and comprises the following steps: acquiring boundary conditions of a design domain and a geometric model in the design domain; performing initial layout on the geometric model in the design domain through the quadrilateral component; the overlapped quadrilateral assemblies are operated, and segmented and recombined convex polygon assemblies are obtained; acquiring a position relationship between the network nodes in the design domain and the convex polygon component, and converting the position relationship into a unit density field; establishing a topological optimization model according to the unit density field; updating control parameters of the quadrilateral component according to the sensitivity of the target function and the sensitivity of the constraint function; and outputting the layout of the convex polygon component in the design domain after the control parameters are optimized as an optimization result until the topological optimization model converges. According to the optimization method for the manufacturability of the welding topological optimization structure, the problems that existing welding topological optimization is poor in manufacturability and complex in structure post-processing are solved.

The invention provides a four-corner lock anomaly detection method based on key point detection, which comprises the following steps: firstly, acquiring a template graph and a task graph of a four-corner lock, acquiring image features and preprocessing, establishing a key point detection network, and determining the anomaly of the four-corner lock by positioning key points (rectangular vertexes, rectangular notch points and circular notch points) in the image and combining geometric vector calculation and angle judgment. Accurate recognition and anomaly detection of the closed state of the four-corner lock are achieved. According to the method, the rotationally symmetrical locking structures can be effectively distinguished, high detection accuracy can be kept under the complex illumination condition, the false detection and missing detection risks are greatly reduced, and the efficient, reliable and safe detection requirements of the subway inspection robot are met.

The invention discloses an ultrahigh-resolution immersive scene rendering method based on hexagonal picture segmentation. The method comprises the following steps: 1, determining a hexagonal segmentation style of an immersive display surface; 2, unfolding the immersive display surface into a plane; 3, acquiring 3D point information of each hexagonal surface, respectively calculating the width W and the height H of the enveloping quadrilateral surface, and calculating a local coordinate system V of the hexagonal surface S; 4, using W, H and V to construct a view cone and a viewpoint matrix of the three-dimensional scene; 5, setting a shade M of a plane expansion view for the hexagonal surface S; 6, calling a rendering scene of the 3D scene for the mask region by using information of the view cone and the viewpoint matrix, and rendering the mask region into a picture at the position S of the hexagonal surface; and 7, repeating the steps 5-6, and sequentially carrying out the same treatment on each hexagonal surface. According to the method and the device, the ultrahigh-resolution picture can be rendered in a scene segmentation form, and the method and the device are suitable for ultrahigh-resolution picture rendering under immersive display equipment.

The invention relates to a region-of-interest extraction method and device for three-dimensional point cloud data, equipment and a medium, and the method comprises the steps: extracting target point cloud data of a target object from original three-dimensional point cloud data, and determining the coordinates of each original end point through a boundary straight line of the target object; after the original end point coordinates are converted into the camera coordinate system through the target rotation angle, second end point coordinates are determined again, all the second end point coordinates form a standard rectangular area, the standard area is the maximum rectangular area based on the camera coordinate system, and then the second end point coordinates are converted into the original coordinate system through the target rotation angle; according to the method, the three-dimensional ROI of the target object can be automatically extracted from the three-dimensional point cloud data of the industrial scene, and the extraction rate and the extraction precision are improved, and the maximum rectangular area is searched in the formed target quadrilateral area, and the three-dimensional ROI of the target object can be determined by combining the height of the target object.

The invention discloses an energy absorption enhancement type lattice structure with the Poisson's ratio adjustable in all directions and a design method, and relates to the field of honeycomb structures. The method comprises the steps that S1, two-dimensional honeycomb structure cell elements with the Poisson's ratio capable of being adjusted according to the thicknesses of inner and outer ribs are constructed; s2, overlapping the two two-dimensional honeycomb structure cell elements in the in-plane direction at 90 degrees, and performing Boolean union intersection operation to obtain four three-dimensional honeycomb units; s3, sequentially connecting the four middle vertexes of each three-dimensional honeycomb unit to form a quadrilateral rib, sequentially connecting the upper vertexes of the four three-dimensional honeycomb units to form a quadrilateral rib, and sequentially connecting the lower vertexes of the four three-dimensional honeycomb units to form a quadrilateral rib to obtain a three-dimensional honeycomb structure cell element; s4, performing array to obtain a three-dimensional lattice structure; when being pressed in the in-plane direction, the two-dimensional honeycomb structure cell element shows the same Poisson's ratio polarity as the corresponding two-dimensional honeycomb structure cell element in the in-plane direction. According to the constructed two-dimensional honeycomb structure cell elements, the overall rigidity of the structure is improved, and a novel three-dimensional lattice structure with Poisson's ratio symbol anisotropy is generated through Boolean operation.

The invention discloses a bulk cargo cabin real-time fusion detection method based on a laser point cloud, and the method comprises the steps: obtaining a real-time three-dimensional scene point cloud of a port scene, and obtaining a deck plane equation and a normal vector; projecting the three-dimensional scene point cloud to a two-dimensional deck plane, and constructing an intensity image taking point cloud intensity as information and a depth image taking projection distance as information; obtaining an intensity mask image from the intensity image; acquiring a depth edge image according to the depth image, and fusing the depth edge image and the intensity mask image to obtain a fused edge image; contour extraction is carried out on the fused edge image, polygon fitting is carried out, a quadrangle in the fused edge image is reserved as a candidate cabin, and a minimum enclosing rectangle of the quadrangle is obtained; and obtaining four vertex coordinates of the minimum bounding rectangle, and back-projecting the four vertex coordinates to the three-dimensional space to obtain three-dimensional space rectangular coordinate points of the final cabin. The method is suitable for a complex environment and a dynamic scene in a port operation area, and the cabin in the dynamic scene can be obtained in real time.

The embodiment of the invention provides a three-dimensional Gaussian sputtering scene rendering method and device based on an unreal engine. The method comprises the following steps: analyzing point cloud data of a three-dimensional Gaussian sputtering scene based on a graphics processor, and obtaining structured point cloud attribute data; mapping each Gaussian point in the point cloud attribute data into a quadrilateral instance, and determining a mapping result; according to the point cloud attribute data and a preset double-tone sorting algorithm, determining a sorting result of Gaussian point depths corresponding to the quadrilateral instance; according to the point cloud attribute data, the mapping result, the sorting result and a preset physical rendering model, processing the obtained light source data in the three-dimensional Gaussian sputtering scene, and determining an illumination calculation precision standard; and according to the distance between the preset camera and the point cloud data in the three-dimensional Gaussian sputtering scene, performing scene rendering by using the point cloud attribute data, the mapping result and the illumination calculation precision standard. According to the scheme, the engine compatibility problem is solved, and the rendering performance is optimized.

The application discloses a kind of poisson ratio each direction controllable energy-absorbing enhanced lattice structure and design method, it is related to honeycomb structure field, method includes: S1, constructs the poisson ratio of two-dimensional honeycomb structure cell that can be adjusted according to inner and outer rib thickness;S2, the in-plane direction of two two-dimensional honeycomb structure cell is mutually coincident and placed 90 degrees, carries out Boolean intersection operation, obtains four three-dimensional honeycomb units;S3, the four intermediate vertices of each three-dimensional honeycomb unit are sequentially connected into quadrilateral rib, the upper vertex of four three-dimensional honeycomb units is sequentially connected into quadrilateral rib, and its lower vertex is sequentially connected into quadrilateral rib, to obtain three-dimensional honeycomb structure cell;S4, array obtains three-dimensional lattice structure;When being compressed in in-plane direction, show the same poisson ratio polarity as the in-plane direction corresponding two-dimensional honeycomb structure cell.The two-dimensional honeycomb structure cell constructed by the application improves the overall stiffness of structure, and generates new three-dimensional lattice structure with poisson ratio sign anisotropy by Boolean operation.

An assembled computer case comprises at least three supporting columns, a first base and a second base, each supporting column is provided with a first assembling structure and a second assembling structure, the first base is arranged on the at least three supporting columns and connected with the first assembling structures of the at least three supporting columns, and the second base is arranged on the at least three supporting columns and connected with the second assembling structures of the at least three supporting columns. The second base and the first base are oppositely arranged, the second base is arranged on the at least three supporting columns and connected with the multiple second assembling structures of the at least three supporting columns, and the second base, the first base and the at least three supporting columns jointly define a quadrangular shell inner frame.

The utility model discloses a double door leaf section bar of an elevator. The door leaf section bar comprises a section bar main body, viewing from the cross section angle of the profile body, the profile body comprises a first inclined plate, a second inclined plate, a first transverse plate and a second transverse plate. The first transverse plate and the second transverse plate are horizontally arranged, the second transverse plate is located under the first transverse plate, and the first inclined plate and the second inclined plate are located on the two sides of the first transverse plate respectively. The first inclined plate, the first transverse plate, the second inclined plate and the second transverse plate are sequentially connected and combined to form a quadrilateral structure, the designed structure of the profile body is firm, all the structures are arranged in the quadrilateral structure, risks such as breakage do not need to be worried about when the profile is installed and used, functions are complete, glass can be installed, and L-shaped corner connectors can also be installed. And the material has multiple purposes. And secondly, the first inclined plate and the second inclined plate adopt large inclined plane design, so that the appearance is elegant, and the stereoscopic impression is strong.

The application provides a flow control method based on three-curved-surface fish scale bionic structure, comprising the following steps: S1, constructing a main structure of an impeller blade, including a suction surface e and a pressure surface f, and fish scale areas g with multiple fish scale bionic structure coupling elements arranged regularly are arranged on the suction surface e and the pressure surface f; S2, constructing and designing a single fish scale bionic structure coupling element, including a bottom surface adhering to a blade surface, a top surface in a fish scale structure, and a rear side cylindrical surface; the top surface comprises two groups of parallel fold surfaces, and each group of fold surfaces is composed of three quadrilateral surfaces; a space rectangular coordinate system is established with a front end point of the bottom surface as an origin, and the fish scale bionic structure coupling element is constructed in the space rectangular coordinate system; and S3, establishing multiple fish scale bionic structure arrangement rules. The application can improve the fluid flow characteristics of the blade surface and reduce noise generation based on the control of flow by bionic structure.

The invention discloses a gradient acceleration optimization method for the wall thickness of a water-entry impact-resistant aluminum alloy honeycomb of an aircraft, and the method comprises the steps: selecting an optimal shape from aluminum alloy honeycombs of quadrilateral, hexagonal and circular honeycomb units, carrying out the axial layering, and generating a plurality of groups of honeycomb unit wall thickness gradient samples; constructing an optimal aluminum alloy honeycomb according to the wall thickness gradient samples of each group of honeycomb units, and constructing an aircraft fluid-solid coupling simulation model to perform impact response simulation at a preset water entry speed to obtain a real sample data set; and expanding a real sample data set, training and verifying a GAN-ANN proxy model, embedding the GAN-ANN proxy model into a multi-objective optimization model, and carrying out iterative solution by taking the peak acceleration and the mass minimization of the aluminum alloy honeycomb as objectives and meeting the peak stress constraint to obtain the optimal wall thickness of each layer of honeycomb unit. According to the optimized aluminum alloy honeycomb wall, the water entry impact load can be effectively relieved, the stress borne by the aircraft body is reduced, and the structural light weight can be achieved.

The utility model discloses a whole-piece type three-dimensional finger stall with an adjustable inner diameter, which comprises a whole-piece type stall body, and is characterized in that the whole-piece type stall body is made of a soft thin material, the main body of the whole-piece type stall body is a sheet-shaped quadrangle, one end of one edge of the whole-piece type stall body is provided with a strip-shaped bulge, the middle part of the edge is provided with a cross-shaped bulge, and the middle part of the bulge is provided with three linear notches; two linear notches are arranged close to the edge of the edge, a T-shaped protrusion and a pointed-cone-shaped protrusion with a linear notch in the middle are arranged on the edge of the edge adjacent to the long-strip-shaped protrusion on the edge, and three long linear notches and two short linear notches are arranged towards the other edge parallel and opposite to the edge. The edges with the T-shaped protrusions and the pointed-cone-shaped protrusions are curled towards the reverse side, the two protrusions penetrate into the corresponding linear notches respectively, the long-strip-shaped protrusions at one end penetrate into the linear notches in the opposite cross-shaped protrusions respectively, the two ends of the cross-shaped protrusions penetrate into the linear notches in the adjacent edges respectively, and the whole body is in a barrel shape with an opening in one end.

The utility model relates to the technical field of mechanical equipment fastening, in particular to a bolt anti-falling assembly which comprises a base plate and a matching component. A matching hole is formed in the substrate; the matching hole is a regular polygon hole; the matching component is thinner than the substrate; the outer wall of the matching component is of a polygonal structure, the number of edges of the outer wall of the matching component is the same as that of edges of the matching holes, and the matching component can be matched with the matching holes. The matching component can be mounted in the matching hole and is limited to rotate by the matching hole; a locking hole is formed in the matching component; the locking hole and the outer wall of the matching component are concentrically distributed; the locking hole is a regular hexagon hole or a regular quadrangle hole; a limiting hole is formed in the base plate; a preset distance is formed between the limiting hole and the matching hole; a plurality of limiting holes are provided; the multiple limiting holes are distributed in an array mode with the center of the matching hole as the circle center. The bolt or nut can be prevented from falling off, the bolt is convenient to replace, and the bolt can be repeatedly used, can be suitable for bolts of various specifications, and is simple in structure and low in use cost.

A heat exchanger plate (1) for a plate heat exchanger for heat exchange at least between a first fluid and a second fluid, the heat exchanger plate (1) having a quadrilateral shape with two oppositely parallel primary sides (5) and two oppositely parallel secondary sides (6) and a longitudinal central axis (x) parallel to the primary sides (5). The heat exchanger plate (1) comprises a corrugated heat exchange region with ridges and valleys having a longitudinal extension defining an inclination with respect to a longitudinal central axis (x), four port holes (11, 12, 13, 14), at least two of which are positioned at respective corners of the heat exchanger plate (1) extending through the heat exchanger plate (1), a first set of ridges (8a) and valleys (9a) and a second set of ridges (8b) and valleys (9b), the longitudinal extension of the first set of ridges and valleys (8a, 9a) defines a first angle (alpha) relative to the first main side (5a) and the longitudinal extension of the second set of ridges and valleys (8b, 9b) defines a second angle (beta) relative to the second main side (5b), where the intersection between the first set of ridges and valleys (8a, 9a) and the second set of ridges and valleys (8b, 9b) defines a transition region (10) comprising a curvature of the ridges and valleys concentric with the port aperture.

Video coding using warped motion compensation is described. Extended rotations for the warped motion compensation can be explicitly signaled. For example, motion parameters for predicting the current block and a rotation angle can be decoded. A warping matrix is obtained using the motion parameters and the rotation angle, and a prediction block is obtained by projecting the current block to a quadrilateral in a reference frame. Also described is determining a prediction model of the current block and obtaining a prediction block by projecting the current block to a quadrilateral in a reference frame. Determining the prediction model can include determining whether to predict the current block using a motion vector, a local warping model, or a global motion model, obtaining motion parameters of the prediction model, decoding a rotation angle, and obtaining a warping matrix using the motion parameters and the rotation angle.

This invention discloses a method for joint evaluation and optimization of buckling and bending of arbitrary quadrilateral laminates based on physical information neural networks, relating to the field of composite material structure design technology. The method, for arbitrary quadrilateral laminates, first constructs a method based on classical laminate theory... USA The stiffness matrix explicitly reflects the influence of ply parameters, and a physical domain is transformed to a reference domain through a bitriangular affine mapping to establish a physical information neural network mechanical model. The model is trained with the goal of minimizing the total potential energy or Rayleigh quotient, solving for the buckling factor and layer-by-layer strain limits, and adapting to four typical boundary conditions through a boundary embedding function. Subsequently, using ply angle and thickness as variables, optimization is performed using a genetic algorithm, with the goal of minimizing mass, and the buckling factor and strain limits as constraints. The final output is the optimal ply scheme that satisfies specific boundary conditions. This invention can optimize ply angle and thickness while satisfying buckling stability and strain strength constraints.