207 results about "Evolution rule" patented technology

The invention discloses a prediction method and visualization method of traffic jam. The methods comprise the following steps: GPS data sent back by a taxicab is utilized for being associated to roads in an electronic map through the map matching method; the road section speed calculated in terms of the matched data is utilized for judging the traffic state of road sections; the evolution rule of the traffic jam, including formation and dissipation of the traffic jam, is extracted with the utilization of the historical data; the traffic jam prediction is performed with the utilization of the sliding time window scheme after a real-time traffic information database is associated; the congestion intensity and the influence range of congested road sections can be presented by a thermodynamic chart after the congestion intensity of the congested road sections is calculated based on the prediction result. The prediction method provided by the invention can realize highly accurate traffic jam prediction, and the visualization method of the thermodynamic chart enables the traffic jam to be visualized and understandable, so that the location and the influence range of the traffic jam can be discerned conveniently.

The invention discloses a prediction method of driving risk based on a hidden Markov model. The method comprises the steps of (1) classifying driving risk states through a cluster analysis method based on vehicle operating characteristics, (2) estimating the influences of a driver behavior and surrounding traffic environment characteristics on a transition probability between driving risk states through multiple logistical models for different driving risk states, (3) with a risk state as a hidden state, with an actual observed vehicle movement variable as a state output value, with multiple logistic model parameters as parameter initial values of a state transition probability matrix, establishing a hidden Markov chain model that reflects the evolution rule of driving states, and (4) obtaining the vehicle operating characteristics in real time and predicting a future risk state based on the hidden Markov chain model. According to the method, the hidden Markov model which can reflect the above characteristic real-time change and has a variable state transition probability is established, the accuracy and prediction accuracy of a driving risk model are improved, and the real-time requirements of anti-collision warning can be satisfied.

The present invention provides a Beidou system-based large-span bridge deformation real-time monitoring method. The Beidou system-based large-span bridge deformation real-time monitoring method includes the following steps of: data acquisition; data processing: a cloud computing data center performs differential processing and filtering processing on original data based on a cloud computing environment to realize the real-time calculation on the original data, obtains calculated bridge deformation data and stores the original data and the calculated bridge deformation data to a database; and data storage and management. According to the method, when the deformation of a bridge is abnormal, some local and overall parameters of the structure of the bridge are picked up precisely in real time through a Beidou positioning system, and the characteristics of the deformation of the bridge which are different from that of the deformation of the bridge in a normal state are identified, so that a damaged position and the corresponding damage degree of the position are determined, and evaluation and early warning are performed; and through the long-term observation of deformation-sensitive characteristic quantity, the evolution rule of the performance degradation of the bridge can be mastered, so that corresponding improvement measures can be deployed, and the service life of the bridge can be prolonged; and the Beidou positioning navigation technology is adopted, so that the accuracy of monitoring and the reliability of prediction and evaluation can be greatly improved.

The invention provides an urban rail transit passenger flow analysis method based on AFC (Automatic Fare Collection) passenger ticket data. The method comprises the following steps: on the basis of historic passenger ticket data of an urban rail transit AFC system, systematically analyzing spatial and temporal distribution character of the urban rail transit passenger flow on the aspects of three levels such as stations, routes / intervals and road networks in combination with an urban rail transit network and an actual train working diagram; and meanwhile, providing a two-dimension / three-dimension visualization technology and a reappear technology of process evolution for the passenger flow spatial and temporal distribution. The method provided by the invention has the relatively good advancement, practicability and universality, the spatial and temporal distribution character of the urban rail transit network passenger flow can be comprehensively mastered from different levels systematically by using the method so as to provide good scientific data and support evidence for the operation management and organization optimization of the urban rail transit, and provide efficient technological approaches for reappearing the spatial and temporal distribution evolution process and researching the passenger flow evolution rule of the urban rail transit network passenger flow.

The invention relates to a pressure rock failure and instability process and dynamic permeability test apparatus and a method thereof. A stress strain signal, a sound emission signal and an apparent resistivity signal in the pressure rock failure and instability process are acquired and processed by using a large pressure rock permeability test device to obtain the stress strain relationship, the quantity and positions of sound emission events and the rock apparent resistivity change rule induced by pressure water permeability increase in large pressure rock failure and instability process in order to obtain the dynamic evolution role of crack expansion, perforation and instability in the rock failure process under hydraulic-mechanical coupling action and the corresponding dynamic permeability. The hydraulic-mechanical coupling failure mechanism and the pressure permeability of rocks, and the deformation and strength characteristics, the crack expansion, perforation and failure characteristics and the permeability evolution rule of pressure water in the crack expansion-perforation-failure process of the rocks under the hydraulic-mechanical coupling action are researched in the invention. The apparatus and the method have important engineering values in realization of safe mining under water pressure on pressure water.

The invention provides a stress corrosion and hydrogen measuring electrochemical in-situ measurement device under a slow strain speed condition. The stress corrosion and hydrogen measuring electrochemical in-situ measurement device comprises an electrochemical work station, an auxiliary electrode, a working electrode, a reference electrode, a stretching test sample, a slow strain stretching machine, a computer, an isolation transformer, a corrosion device and a hydrogen measuring device. The stress corrosion and hydrogen measuring electrochemical in-situ measurement device has the effects that an electrochemical in-situ test can be carried out on stress corrosion and hydrogen permeation respectively under the slow strain speed condition through replacing a corrosion electrolytic tank; the device has the characteristics of adjustable test sample size, in-situ electrochemical measurement, accurate load-displacement readings, simple structure, convenience and flexibility in utilization, simplicity in operation and the like. The device can be used for simultaneously realizing in-situ electrochemical behavior detection of pull stress, corrosive liquid, corrosive gas and temperatures, and can be widely applied to researches of strain speeds, the pull stress, types and concentrations of corrosive media, pH values, temperatures, corrosive gas partial pressure and concentration and influences on corrosion of metal materials by hydrogen brittleness, and a damage evolution rule of materials can be analyzed through electrochemical data.

The invention relates to a PID controller parameter optimizing method, and especially discloses a PID controller optimizing design method based on a particle swarm membrane algorithm. The method comprises that an optimal particle is obtained from a swarm, different dimension values of the particle are successively assigned to to-be-optimized parameters Kp, Ki and Kd, a control system model is operated, performance indexes output by the system are obtained, and it is determined whether the evolution rule is used again to search for the optimal particle so that the optimal control effect can be obtained. The PID controller optimizing design method combines membrane computing with traditional PSO (Particle Swarm Optimization), fully utilizes the partition function and transport communication rules, can obtain a set of more proper PID control parameters, and finally enables a controlled system to achieve the optimal control effect. According the PID controller optimizing design method, the controlled system can obtain the set of more proper PID control parameters and achieves the optimal control effect under the condition that the controller structure is not changed.

The invention relates to a cell-machine based dynamic scheduling method for a large part flexible job shop, which comprises the steps of: 1) establishing a gridding model of a cell machine; 2) describing the cell state; 3) defining initial and entrance boundary conditions of a whole model system as beats of particles entering the system, wherein the exit boundary condition is reception capacity of a downriver factory of a supply chain on products; 4) determining the self-organized evolution rule of the model; and 5) for the work station selecting rule R[p--c], taking completion of the jth step as the start point and completion of the (j+1)th step as the finish point, taking the period (wq+w1 / pe) as a measuring standard, selecting the work station with minimum (wq+w1 / pe) as the processing work station of the (j+1)th step, wherein the work sequencing rule R[c--p] is determined according to a ''first come first serviced'' rule with the combination of workpiece processing priority. According to the cell-machine based dynamic scheduling method for the large part flexible job shop, the operating efficiency is improved and the stability of the device is enhanced.

The invention relates to a population distribution spatial-temporal evolution and cognition method considering urban pattern characteristics. The population distribution spatial-temporal evolution andcognition method comprises the following steps: 1) carrying out scale conversion of multi-source and multi-scale remote sensing images; 2) extracting urban information based on the multi-source remote sensing image; 3) analyzing a multi-scale urban pattern-structure-function spatial-temporal relationship; 4) carrying out spatial-temporal correlation and coupling analysis on population distribution and urban characteristics; 5) constructing a population distribution simulation and prediction system considering urban pattern characteristics; and 6) carrying out spatial-temporal monitoring and cognition on population distribution in different scenes. The population distribution spatial-temporal evolution and cognition method has the advantages that population general survey and statistical data, multi-scale remote sensing data and multi-source land utilization / coverage data are used as data sources; the spatial-temporal characteristics and the evolution rule of the multi-scale urban spatial pattern are studied, and the population distribution spatial-temporal evolution model considering the town characteristic pattern is constructed, and the boundary of the population distribution density is finely described from the multi-level spatial scale, and a theoretical basis and a technical support are provided for population resource utilization and policy adjustment and social and economic resource allocation.

The invention discloses a pressure head device for loading normal triaxial rheology and testing acoustic emission under high confining pressure. Vaseline is applied on a piezoelectric ceramic surface of a sensor, the sensor is placed into a sensor room and fixed at the bottom, a flexible spacer is placed between the sensor and a fastening bolt, the fastening bolt, a side seal ring and a side seal cover are installed in a side seal chamber through a slot of the fastening bolt, a sticky steel type structural adhesive is poured into a recess part and an outlet hole of the side seal cover, a main seal ring is arranged into a seal groove, a main seal cover and a pressure head seat body are sealed through the bolt of the main seal cover, a storehouse seal ring and a storehouse seal cover are installed in a storehouse seal chamber, a lower pressure head centering guide slot centers the center of a testing system pressure axis, an upper pressure head is arranged on a rock sample, and coaxial cables of the upper pressure head and the lower pressure head are linked through convex-concave joints of coaxial cable yarns. The invention is widely used for indoor emission tests of failure mechanisms, failure modes and damage evolution rules of soft and hard rocks in the rheology process.

The invention provides a fatigue testing machine and testing method capable of synchronously radiating a light source for in-site imaging. According to the composition of the testing machine, a cross at the bottom of a bottom plate is embedded to a synchronous light source radiation platform; a servo motor of the bottom plate is connected with the lower end of a lower clamp on a base of the bottom plate through a cam link mechanism; a semi-annular organic glass inner cover and a semi-annular organic glass outer cover are movably embedded to the upper surface of a cover plate of the base, the organic glass inner cover and the top of the organic glass outer cover are connected with a top cover in an embedded mode, the middle of the bottom face of the top cover is connected with the upper end of a load sensor, and the lower end of the load sensor is connected with an upper clamp; the upper clamp is located over the lower clamp; the servo motor and the load sensor are both electrically connected with a data processing and control device. In the fatigue testing process of the testing machine, synchronous radiation imaging can be performed on fatigue testing samples, and a three-dimensional image in a material is obtained; the mechanical properties of materials and the evolution rule of a microscopic structure can be more clearly and accurately reflected.

The invention discloses a mine fire escape route cellular automaton optimizing and guiding method, and belongs to mine fire safe escape methods. An underground monitoring subsystem, a smoke plume migration simulation subsystem, an escape route selection subsystem and a rescue and escape command guiding subsystem are included, and the monitoring system is composed of a ground central station and various underground sensors and monitors temperature, gas and flue gas parameters in real time; the smoke plume migration simulation system simulates dynamic evolution rules of underground fire smoke through FDS software; the escape route selection subsystem applies a cellular automaton for building a mathematical physical model under the mine ventilation network structure actual condition, dynamically quantizes the complex roadway environment and the smoke pollution range, calculates the escape efficiency and determines the best escape route; the rescue and escape command guiding subsystem provides guidance for underground escape persons on the basis of the escape route calculation result, and the best escape route is fed back to underground workers by means of an upper computer and an underground voice alarm system, the escape efficiency is comprehensively improved, and casualties are reduced to the maximum extent.

The invention relates to a method for predicting hot rolled steel austenite static recrystallization structure evolution and provides a hot rolled austenite static recrystallization structure evolution prediction method by taking a strain capacity epsilon 0.5 required for the static recrystallization of 50 percent of austenite as a core. The method comprises two parts, i.e. predicting an austenite static recrystallization structure evolution rule by taking typical interval in pass trf and strain rate as boundary conditions, and conducting prediction and correction aiming at the different intervals and strain rates of practical hot rolling passes. By adopting the method, the accurate prediction of the austenite static recrystallization structure evolution rule can be realized through fewer parameters, the optimized setting of hot rolling technological parameters can be realized accordingly, the number of basic tests can be reduced, the development period of steel types can be shortened and the method is suitable for the steel types such as C-Mn steel, C-Mn-Nb steel and the like which require for rolling control.

The invention discloses a ballastless track damage analysis method performing combined solution based on definite element expansion and fatigue analysis. The method includes the following steps that a definite element model of a ballastless track is built; needed loads and boundary conditions are applied to the definite element model, and stress analysis is performed on the definite element model; a stress analysis result is imported into fatigue analysis software, and fatigue performance analysis of the definite element model is performed; based on a definite element expansion method, fracture mechanics parameters of materials of the track structure are defined in the definite element model, service life critical portions obtained during fatigue performance analysis are selected as damaged regions, and generation of damage and a continuous development evolution rule are calculated; a train wheel track coupling model is added on the definite element model, damage is applied to the truck structure, the transverse acceleration, the vertical acceleration, the derailment coefficient and the wheel weigh load reducing rate of a train are calculated after the damage happens to the track structure, and influences of the damage on running of the train are analyzed.

The invention discloses a bus passenger flow evolution analysis method based on time-space data fusion. The method comprises the following steps: 1, a historical time-space data preprocessing step; 2, a step of calculating trip get-off probabilities; 3, a bus passenger flow time-space evolution analysis step; and 4, a multi-dimensional passenger flow time-space distribution feature analysis step, i.e., according to an obtained time-space network and flow of corresponding time-space network arc segments, drafting a bus time-space distribution feature graph. The analysis method provided by the invention has the following advantages: 1, the trip get-off probabilities are obtained based on enormous historical time-space data statistics, the precision is quite high, the scheme is simple and practical, the solving efficiency is high, and correlation operation indexes of a whole city bus system can be rapidly solved; and 2, the real-time performance is good. Besides, based on the calculated and stored trip get-off probabilities, station OD is calculated in real time through combination with bus get-on passenger flow, and accordingly, the time-space evolution rule of line passenger flow can be dynamically reflected in real time.

The invention relates to a three-dimensional physical simulation experiment for developing mining overlying strata movement deformation and goaf gas transport rules by using similar materials, in particular to a miniature three-dimensional physical similarity simulation experiment table of goaf gas transport rules, wherein the miniature three-dimensional physical similarity simulation experiment table is used for conducting mine ground pressure and goaf gas transport in a laboratory under the three-dimensional condition. The experiment table comprises an experiment table box body, a double-rocker mining system, a controllable ventilation system, a gas injection system, a drainage system and a testing system. The experiment table is suitable for being used for conducting physical similarity simulation experiments on mining-induced fracture evolution rules and the goaf gas transport rules under the three-dimensional condition. The miniature three-dimensional physical similarity simulation experiment table of the goaf gas transport rules can meet the requirements for further developing the mining pressure relief gas transport rules and improve a coal and gas safety co-mining theoretical system.

The invention discloses a device and a method for measuring toughness damage evolution in process of metal uniaxial tension. The method includes a first step of utilizing a camera and a direct-current low-resistance tester to simultaneously record images and resistance of a sample in the stretching process, wherein the sample is sprayed with random free speckles, a second step of obtaining a strain field of the sample in the stretching process through a digital image correlation DIC) method, and a third step of combining strain increment and resistance increment of the sample in the stretching process to indirectly obtain a damage evolution rule in the stretching process.

The invention discloses an in-situ measurement device and a measurement method of a scattering coefficient spectrum of an atmospheric aerosol. The measurement device comprises an integrating sphere, a solar simulator, a fiber spectrometer and a computer, wherein an internal reflectance coating of the integrating sphere is made from polytetrafluoroethylene, and collection efficiency of the scattered light is improved based on the advantage of truncated corners of the internal reflectance coating, so that the sensitivity in the measurement of the scattering coefficient spectrum is effectively strengthened. In the device and the method, a measure equation for the scattering coefficient spectrum in a wave range from 350 nm to 1000 nm is established, so that the difference of conversion responsivity caused by the difference of the wavelength in a photoelectric conversion process can be effectively avoided. The device and the method can detect evolution rules of the scattering coefficient spectrum of the atmospheric aerosol with the temperature, the humidity and the atmospheric pressure, and have the characteristics of being simple in principle, convenient in operation and fast in detection speed.

The invention discloses an analysis method for studying the rock joint surface shearing damage process and a test system. The method comprises the following steps of using a mold taking material to rub and print the surface form of a natural rock joint surface; making a rock-like material test sample with the same surface form and mechanical parameter as natural rock by using a natural rock jointcurve surface mold; controlling different boundary conditions on the test samples to perform rock joint shearing tests, thus obtaining joint surface shearing macroscopic property parameter and featurevalues; in the shearing test process, using the sound emission to monitor the microcosmic evolution rule and energy features of the damage process of the surface of the joint surface, joint surface upper and lower rock block and anchoring structures; performing joint surface scanning by a three-dimensional laser scanning instrument before and after the shearing test, thus obtaining geometric evolution features of the joint surface damage; precisely expressing the damage property of the joint surface in the shearing process and the quantitative characterization thereof by combining the macroscopic property parameter and feature values of the joint surface shearing, the microcosmic evolution rule of the damage process, the energy features and the geometric evolution features.

The invention discloses a mining and auxiliary decision intelligent system for traditional Chinese medicine text medical records and relates to the technical field of natural language processing and traditional Chinese medicine diagnosis auxiliary information. The system is based on unstructured text medical record of real standard clinic medical record; automatic traditional Chinese medicine principle-method-recipe-medicines, treatment according to syndrome differentiation and knowledge extraction and expression are realized; the system comprises a database which is in a rear end server and traditional Chinese medicine and pharmacy knowledge atlas on-line\off-line applications in a front end computer; major formulas, symptom pairs, syndromes, traditional Chinese medicine pathogenesis evolution rule and data links of mutual relation among the above knowledge elements are stored in the database according certain data storage structure. Through the map node retrieval, node set retrieval and area positioning of the traditional Chinese medicine and pharmacy knowledge atlas, the obtained analysis results are mixed with features such as directed network, semantic distance, coordinate setting and topology analysis based on hierarchical cluster, which greatly increases the discovery capability of major formulas, symptom pairs, syndromes, traditional Chinese medicine pathogenesis evolution rule and mutual relation among the above knowledge elements.

The invention discloses a fire ventilation and smoke discharging experimental simulation apparatus based on an expressway-railway shared double-layer shield tunnel system. The expressway-railway shared shield tunnel fire ventilation and smoke discharging simulation experimental apparatus comprises a tunnel semi-transverse smoke discharging control and optimization system, a simulation fire source system, a multi-characteristic-parameter measurement system, a fire detection system and a water mist extinguishing system; the simulation fire source system is used for simulating a fire source and an occurrence position of the fire source, the fire detection system is used for sensing the occurrence of the fire and issuing an alarming signal, the multi-characteristic-parameter measurement system is used for acquiring multiple characteristic parameters of the fire, the tunnel semi-transverse smoke discharging control and optimization system is used for discharging the smoke of the fire, and the water mist extinguishing system is used for controlling the fire. The fire ventilation and smoke discharging experimental simulation apparatus can simulate the fire situation occurring in a real expressway-railway shared tunnel and provides a simulation experimental platform for comprehensively and systematically researching the control and optimization of the smoke, detection of the tunnel fire under a complicated situation, extinguishment and control of the fire, distribution evolution rule of carbon oxide and the like, so that a better implementation scheme can be provided for designing the personal evacuation when fire happens in the real tunnel.

The invention aims at providing a multi-target spectrum allocation method based on an undisposal order preference quantum goose group algorithm, which comprises the following steps of: building a graph theory coloring model of cognitive radio spectrum allocation, initializing the position of the quantum geese and the quantum speed, carrying out the undisposal order preference and congestion degree calculation on individuals in the population according to the adaptability, sequencing the individuals with the same undisposal order preference levels in sequence from higher congestion degrees to lower congestion degrees, carrying out evolution on the population by a quantum goose group evolution rule, generating new quantum speed and position, carrying out undisposal order preference on obtained solutions in an elite solution set nonDomQGSAList and selecting the solutions with the undisposal solution level being 1 as the final Pareto front end solution set. The method solves the discrete multi-target optimization problem, designs the novel undisposal order preference quantum goose group algorithm as the evolution strategy and has the advantages that the convergence speed is high, and the precision is high. In addition, the method provided by the invention has a wider application range.

The invention discloses an opportunistic network link prediction method and device, and a readable storage medium. The method comprises: slicing sample data to obtain a plurality of sub-sample data, and dividing a connection number and a connection time of a node pair in each sub-sample data into a corresponding network snapshot; converting the connection number and the connection time of the nodepair in each network snapshot into a connection weight, and mapping an identifier of the node pair and the node pair connection weight in each network snapshot into a time series vector sequence; acquiring node attribute information in each network snapshot to construct an attribute vector, and constructing an attribute vector sequence; constructing a Bayesian deep learning model, training and testing the model by using the time series vector sequence and the attribute vector sequence to obtain a target model, and predicting the opportunistic network link by using the target model. The methodand the device can accurately grasp the evolution rule of opportunistic network node pairs in the time domain and accurately predict the opportunistic network link.

The invention discloses a device for testing electric conductivity and soil-water characteristics of loess. The device comprises a base, wherein a sleeve is arranged on the base; a pull rod is arranged in the sleeve; the sleeve is divided into a plurality of layers from top to bottom; each layer of the sleeve is connected with a resistivity measuring system, a suction measuring system and a moisture measuring system; a porous plate is arranged at each of two ends of the sleeve; an upper cover plate is arranged on the porous plate at one end of the sleeve; and a pressure rod is arranged on the upper cover plate. The device for testing electric conductivity and soil-water characteristics of loess realizes the purpose of simultaneously obtaining the resistivity and soil-water characteristic curve of the loess on the same equipment, realizes automatic measurement, enables data acquisition to be convenient and reliable, records the resistivity, moisture volume percentage and suction evolution condition of the loess at any time, can reflect the microscopic evolution rule of moisture migration in the loess, and can realize loading-unloading and simulation of long-term deformation characteristics of remolded loess and the moisture migration and pore state evolution rule in the loess.

The invention discloses a fire dynamic emergency decision system based on accident evolution and an implementation method thereof. The system includes an unmanned aerial vehicle (UAV) detection platform or a personal portable detection device, a data communication transmission device, an accident scene command vehicle information processing server, a command center server and an emergency decision-making command system platform for information exchange and decision analysis. In accordance with that characteristic of the accident scene, the technical requirements of disposal and the dynamic information parameters of the accident site, according to the real-time monitoring of fire temperature, heat radiation, ambient wind speed and gas concentration, and the predicted accident evolution rules and consequences, the dynamic emergency response plan elements are automatically matched from the dynamic emergency response plan elements database, and the dynamic emergency response plan is generated, and is output at each display terminal in a multi-layer plotting mode. Quantitative and graphical display of accident development trend and accident consequence is realized, which provides decision support for accident emergency disposal command.

The invention discloses a physical model testing system and method for landform evolution of a tidal flat-tidal creek system, and belongs to the technical field of landform evolution tests of the tidal flat-tidal creek system. A physical model comprises a tidal flat-tidal creek simulation area, a water circulation system, a water level measurement and control system and a microrelief laser scanner, and can realistically simulate a tidal flat-tidal creek landform evolution process of a coastal zone. The development and evolution rules of the tidal flat-tidal creek system and the change rules of the flow velocity with the water depth are obtained by acquiring tidal flat-tidal creek topographic data of all testing stages, a preset water level process and an actual water level process of a tidal flat-tidal creek simulation zone and trace particle movement images recorded by a camera in a testing process.

The invention discloses a space-time clustering method for information acquisition of a public security event. The method comprises the steps of extracting information about the public security event in network text, and conducting clustering processing; then, conducting visualization; analyzing the influence range, development process, possible results and the like of the public event. Through the adoption of the space-time clustering method for the information acquisition of the public security event, after the public security event occurs, in combination with an event type and event keywords, the effective information about the event can be quickly extracted from social websites, and therefore through a space-time clustering algorithm and a map visualization system, the development process and evolution rules of the event are obtained efficiently, the determination of a solving decision for the public event is facilitated, and the solving efficiency of the public event is improved.

The invention relates to a three-dimensional cellular automaton based lightweight model and optimizing method, comprising operation steps: firstly, performing space dividing on an input network model with an octree, then according to design demands, establishing neighborhood information based cellular evolution, then, defining the relation that a neighborhood information based cellular automaton combines with FEA feedback information based finite element analysis, establishing FEA analysis feedback evolution, and generating a lightweight structure based on two evolution rules. A feedback based optimizing strategy is established, simulated information can be fed back to a design flow, and a drive structure is optimized to change macro attributes of a design target. Finally, the generated lightweight model is subjected to surface recreating and related parameters verifying, and an experiment proves that the invention is very suitable for establishing a 3D (three-dimensional) printing lightweight model.

The invention discloses a method for measuring a yield surface of a metal material. The method utilizes a prestretching-torsion deformation loading path to determinate a later yield surface evolution rule and comprises (1) preparing a stretching-torsion combined test sample according to material mechanical test standards, (2) determining a stretching and torsion stress-strain curve and determining stretching and torsion yield strength values, (3) determining an initial yield surface, (4) determining a prestretching-torsion pre-deformation loading path to realize prestretching-torsion pre-deformation loading, (5) determining a later stretching stress-strain curve and determining stretching yield strength after pre-deformation, and (6) determining a later yield surface. The yield surface determined by the loading path has obvious shape change, shows plastic deformation anisotropic behaviors of the metal material in a complex loading way and is especially suitable for metal materials having strong anisotropic mechanical properties.