209 results about "Particle model" patented technology

The invention relates to a soft tissue deformation simulation method based on smooth particle hydrodynamics, belonging to the technical field of graphic processing. In the method, a smooth particle hydrodynamics method is selected, and a viscoelastic mechanics model is used for reflecting the biomechanical characteristics of soft tissue. The method comprises the following steps of: constructing a series of equations related to soft tissue deformation simulation according to the viscoelastic model; selecting a proper support domain search strategy and a smooth kernel function, approximately calculating each related item of the equation by adopting the particle approximation method, and calculating the variation values of the density, the position, the velocity and the like of each particle along with time through the display integration method; and dynamically outputting the status of each time step size of the particle model to a screen, rendering texture irradiation, and displaying the real-time deformation process of soft tissues and organs under stressing conditions. The method does not need troublesome grid computing, thereby increasing the accuracy and the real-time performance of soft tissue deformation simulation.

The invention discloses a long-life rapid charging method for a lithium ion battery, and relates to the field of research of new energies. The invention is to solve the problem that the traditional lithium ion battery is low in charging efficiency and large in damage to the battery during a charging process. According to the method, an improved single-particle model is established for the lithium ion battery; the mechanism parameters of the battery in the improved single-particle model is obtained by using an excitation response analysis method; according to the mechanism parameters of the battery, the embedded lithium rate on the active substance surfaces of the anode of the battery is obtained; the size relationship between the embedded lithium rate on the active substance surfaces of the anode and a set threshold is obtained by comparison, and the charging current size and charging time of the battery are controlled according to the size relationship, and thereby the rapid charging of the lithium ion battery is achieved. The method is applied to the long-life rapid charging of the lithium ion battery.

The invention discloses a near-distance air combat automatic decision-making method based on single-step prediction matrix gaming. The method comprises the following steps: step 1, erecting a six-degree-of-freedom nonlinear unmanned combat air vehicle control law structure; step 2, initializing a matrix gaming chessboard; step 3, according to the gaming chessboard, carrying out single-step prediction calculation; step 4, calculating a payment function matrix; step 5, carrying out strategy selection through a minimax algorithm; step 6, updating a six-degree-of-freedom plane kinetic and dynamic equation; and step 7, determining whether an air combat termination condition is reached. The method has the following advantages: compared to a three-degree-of-freedom particle model, the actual application value is higher. At the same time, a conventional matrix gaming method based on a maneuver library is changed to be based on a maneuver library of an instruction model, what is needed is only prediction of a step length of a single step, the decision-making time is effectively reduced, the requirement for real-time performance of air verification is satisfied, the method can be better adapted to complex dynamic baffle field environment change, and the combat capability of an unmanned combat air vehicle in a near-distance combat is improved.

The invention discloses a method for generating a control assistance decision instruction based on required time of arrival (RTA). The method comprises the following steps of: constructing an aircraft initial intention model, an external environment model and a particle model required by four-dimensional flight path prediction; and performing flight path prediction on an aircraft to obtain an initial four-dimensional flight path and the estimated time of arrival of a waypoint; obtaining the RTA of the waypoint by using a flight ordering and conflict release function in a control automation system or a control auxiliary decision system; optimizing the initial four-dimensional flight path of the aircraft; displaying the predicted horizontal trajectory and the vertical profile of the aircraft in an air traffic control assistance system and directly generating a control instruction that should be issued by a controller to a pilot. The method quickly generates the control instruction through the flight path prediction and flight path optimization. The instruction and the flight path planned by the method are easy to operate and good in controllability to the pilot, and can enable the aircraft to pass the waypoint according to the required arrival time.

The invention discloses a particle flow simulation system and method on the basis of GPUs. The method includes: generating particle information according to particle modeling information input by a client, and generating geometry information; receiving the particle information and the geometry information, determining that which GPUs in which computational nodes are used according to the number of particles and the number of idle GPUs in the computational nodes, determining that which particles are calculated by which GPUs in which computational nodes according to the determined number of the GPUs and distribution condition of the particles in space, and performing distribution according to determined results; calculating stress of each particle caused by impact of the particles in a plurality of GPUs in a parallel mode, and working out accelerated speed further so as to simulate particle flow; showing simulation results. According to the particle flow simulation system and method, high-density particle virtual experiment simulation can be achieved, energy consumption is reduced, and meanwhile calculation efficiency is improved.

The invention relates to a three-dimensional visualized algorithm for maritime oil spill, which is realized in a way that: on the basis of drawing a large-scale sea level scene, dividing an oil spill process within a short time scale into an oil film self-spreading stage and an oil film drift diffusion stage, and calculating the oil spill loci of the two stages respectively by selecting an Lehr model and an oil particle model; simulating the oil particle model by using a particle system; and visualizing the oil spill loci on the simulated sea level by utilizing a planar refraction technology, accessing the veins in a fragment shader of a GPU by projecting vein coordinates, and simulating and reproducing the three-dimensional scene of maritime oil spill while drawing the sea level refraction effect. The algorithm solves the problems of simulation of the oil particle model, visualization of the oil spill loci on the simulated sea level, and the like, and realizes the vivid and visual simulation of the three-dimensional movement change process of oil spill within a short time scale.

The invention discloses a balance control method for a lithium-ion battery pack, belongs to the field of new energy research and aims at solving the problem of poor balancing accuracy in traditional battery pack balance control. The method comprises the following steps: (1) building a single-particle model for lithium-ion batteries; (2) exerting different excitations on single batteries in the battery pack for balance control and obtaining mechanism parameters of the batteries; (3) detecting status data of the single batteries in the battery pack, and calculating SOC values of the single batteries by the obtained mechanism parameters of the batteries and the status data according to the built single-particle model; (4) obtaining a balance current and balance time by the obtained SOC values of the single batteries according to the requirements of charging balance or discharging balance; and (5) carrying out energy balance control on the single batteries in the battery pack by a balance energy transfer circuit according to the obtained balance current and balance time. The balance control method is used for controlling charging and discharging of the lithium-ion battery pack.

The invention relates to the field of high-performance computer numerical simulation technologies and discloses a design project facing the nodes in a multi-layer directly-connected cluster parallel computing system, which consists of a plurality of logic circuit units having independent operation, storage and communication functions. The logic circuit unit at least has a logic circuit unit being a communication unit capable of directly communicating with other nodes. The other logic circuit units are computing units that execute computation task. Every computing unit is at least in direct communication with the communication unit. The units are different in function and the combination thereof makes the constitution of the node more abundant, flexible and more reliable between nodes and can improve the computing efficiency of node such that the multilayer directly-connected cluster parallel system can much more effectively execute particle simulation.

An abrasive particle morphology database creation method based on a conditional generative adversarial network comprises: deeply mapping three-dimensional abrasive particle images to form two-dimensional images, and the two-dimensional images serving as output target images in a training sample; constructing an abrasive particle model according to the real abrasive particle image, which mainly comprises an abrasive particle contour, abrasive particle color filling and surface texture representation symbols, and taking the constructed abrasive particle model as an input image of a CGAN training sample; inputting the paired input images and the target image as samples of the CGAN into a network for training, and generating a generator for expanding the samples by the CGAN; and finally, carrying out network testing by using the input image as an input, counting an error between the generated image and the target image by using a discriminator, and finally judging whether the image is the target image or the generated image. According to the method, the effectiveness of loss function evaluation is improved, the accuracy of the network output image is also improved, and the similarity between the network output image and the real image is very high.

The invention discloses a coagulation phenomenon simulation method based on a particle model. The method includes the steps that 1, discrete modeling is conducted on the phenomenon that gas coagulates on the solid surface, wherein the influence of the dew point temperature and the relative humidity property in a humidity diffusion model on the details of the coagulation phenomenon is considered; 2, a soil-liquid coupled boundary density correction algorithm is proposed, the problem of particle loss of a smoothed-particle hydrodynamics model at the boundary is solved, and meanwhile particle penetration is prevented under the condition that the time step is not decreased; 3, a particle system is used for conducting discrete modeling on air, the simulation process can be expressed more visually, and adjustment and design can be conducted easily. By applying the method, the flow property, heat conduction property and the like of air can be conveniently adjusted, and the problems that existing air heat exchange phenomenon simulation is not visual in effect and lacks enough details are solved; the method has certain practical value.

The invention discloses a real-time snowflake deposition simulation method based on a particle system model. The real-time snowflake deposition simulation method is characterized in that snowflake particles are divided into computer-simulated falling snow particles and computer-simulated accumulated snow particles. The method comprises the following steps that: (1) when the snowflake deposition simulation is started, falling snow particles are established and drawn by a computer-simulated falling snow particle model, and the falling snow particles fall from random height circularly; (2) when the falling snow particles fall to a position which is a predetermined height away from a computer-simulated scene ground, a computer-simulated accumulated snow particle model is used for receiving coordinate information of the falling snow particles, and new accumulated snow particles are drawn through a computer at the coordinate position; and (3) dot deposition and surface deposition of the drawn accumulated snow particles are realized on the computer-simulated scene ground. By the method, influence on the falling of snowflakes caused by a wind speed, a wind direction and a gravity field is reflected through the coordinate transformation of the falling snow particles; and the method is high in real-time performance and allows people to feel reality.

The invention discloses a piezoelectric sensor-based on-line measurement device and method for particle size distribution, which belong to the field of gas-solid two-phase flow on-line measurement technique. The on-line measurement device is characterized in that: a collision induction probe is inserted in the middle of a gas-solid two-phase flow pipeline; a piezoelectric sensor is arranged on the collision induction probe; a signal conditioning plate and a data acquisition module are connected with the piezoelectric sensor and a signal processing system; when solid particles are collided with the collision induction probe, the piezoelectric sensor senses a particle collision signal and sends the particle collision signal to the signal conditioning plate and the data acquisition module; and the particle size distribution is obtained through signal processing software and a collision particle model. The device has the characteristic that the piezoelectric sensor is utilized to obtain the collision signal of small particle collision directly so as to realize real-time monitoring on the particle size distribution; the influence of background noise on the collision signal is reduced; and a collision dynamics principle is utilized to build a mathematical model of the collision signal and the particle size, so that the size distribution of measured particles in the pipeline is obtained.

The invention discloses a urban earthquake secondary fire simulation method and system, wherein the method comprises: establishing a multi-particle model of regional buildings according to building attribute data, and performing nonlinear time-procedure analysis on the multi-particle model of the regional buildings to obtain the destructive state of each building; calculating the fire probabilityof the building according to the destructive state of each building and a regression-restricted building fire model to obtain the number and the positions of fire buildings; according to a secondary fire spread physical model and the destructive state of each building, simulating a fire spread condition caused by the fire buildings, and obtaining a building indoor fire spread state and an inter-building fire spread state; performing rendering and flue gas treatment on the building indoor fire spread state and the inter-building fire spread state by fire scene rendering and large eddy simulation, and simulating a urban earthquake secondary fire through a preset three-dimensional model. The method can improve the accuracy of earthquake secondary fire simulation and realize the high-reality display of urban earthquake secondary fire.

The invention relates to an air flow simulating method based on physical simulation. The method converts low-speed particles into a grid model by solution of the traditional particle model, and simultaneously transfers high-speed particles to a temporary grid model while solving, and finally outputs grid model results and density field superposed by the temporary grids and renders. The invention also provides an air flow simulating system based on physical simulation. The method and the system thereof can effectively carry out simulation requirements of air containing low-speed and high-speed air simultaneously and can provide greater expression capability and more real simulation effect.

The invention discloses an on-line estimation method for the state of charge (SOC) of a lithium ion battery based on an extended single particle model. The method comprises the following steps: 1) establishing a lithium ion battery single particle model; 2) solving the concentration distribution problem of liquid-phase lithium ions based on a BP (Back Propagation) neural network; 3) solving liquid-phase lithium ion concentration distribution of each area in the single particle model using the trained BP neural network to optimize the single particle model; and 4) implementing on-line estimation of the SOC of the lithium ion battery by adopting unscented Kalman filter based on the extended single particle model. The method considering the liquid-phase lithium ion concentration distribution of each area in the single particle model improves the simulation precision of the single particle model, and overcomes the defect of low precision of the single particle model under medium and high multiplying power conditions. The extended single particle model can better describe the nonlinear characteristic of the battery, and the SOC precision estimated by adopting unscented Kalman filter based on the extended single particle model is higher.

The invention is suitable for the technical field of unloading elephant trunks, and provides a space transhipment unloading elephant trunk design method based on a discrete element method, wherein a space transhipment unloading elephant trunk is composed of discrete elements of each segment. The design method comprises the following steps of: building a three-dimensional model of the discrete element of each segment through a three-dimensional software, and importing the three-dimensional model in a discrete element model software EDEM; creating a particle model of the material to be conveyed by the unloading elephant trunk, and importing the particle model of the material in the EDEM; determining simulation parameters, wherein the simulation parameters include operating speed and particle conveying quantity of a superior unloading device and a lower receiving device, and also include own material attributes of the particle and the discrete element, and contact attribute between the two; finishing simulation, and outputting simulation result. According to the invention, the discrete element method is introduced in the design process of the space transhipment unloading elephant trunk, movement locus of material flow in the elephant trunk can be fitted accurately, and variation of stress on each part of the elephant trunk can be calculated.

The invention discloses a soft tissue deformation modeling method based on virtual springs. The soft tissue deformation modeling method based on virtual springs is based on the spring-particle model to establish an improved real-time deformation model of soft tissue, virtual body springs are added by the topological structure soft tissue surface model combining the square and the isosceles right triangle, so that a more real deformation effect is achieved; at the position of each particle in the system, the superposition of surface springs variable is equivalent to the surface deformation of an object, the resultant force of the elastic forces of the virtual springs is equivalent to the contact force on the surface of the object; the model inherits the advantages of the classical spring particle model that the principle is simple, the model is easy to establish, the calculation speed is quick, at the same time, the model has an ability to control the deformation area.

The invention discloses a simulation method for the film formation value of mud of a slurry shield machine. Through combined usage of a granular distinct element method and a computational fluid dynamic method, a skeleton particle model and a two-phase medium mud model according with Bingham fluid characteristics in skeleton pores are established, and simulation of a film forming experiment of mud is carried out. Meso-structure parameters are obtained through laboratory test, composition of tunnel face skeleton particles is simulated, composition of fine particles in mud is simulated, grouting pressure boundary conditions are applied, value simulation is carried out, and whether a mud film is formed in the tunnel face skeleton particles is determined in a microscopic view. According to the invention, improvement measures can be brought forward to preparation of slurry according to simulation results, so a film forming effect is improved and the method is of guidance meaning to practical engineering.