39 results about "Transportation simulation" patented technology

A method for estimating travel demand in a transportation network includes receiving a dataset of trips. The trips were taken in the transportation network and are each represented by an origin-destination pair and a departure time. A trip can include a sequence of legs. Each trip is described by a vector of modalities. For trips that include the sequence of legs, boarding and alighting stops are estimated. An empirical trip distribution is generated for each modality for given origin-destination stops. The empirical trip distribution is fitted to a specific family of probability distributions. At least one of the generating the empirical trip distribution for a given modality and the fitting the empirical trip distribution to the probability distributions is performed with a processor.

An intelligent car and a positioning method for an intelligent transportation physical simulation platform. The present invention is different from the radio frequency identification method in the application of electronic license plates. When realizing the positioning and navigation of the intelligent car, the card reader is placed in the car, and the passive electronic The tags are laid on the road, and each passive electronic tag corresponds to a coordinate in the global coordinate system. When the smart car passes over the passive electronic tag, the card reader recognizes the UID of the passive electronic tag and determines the UID of the passive electronic tag. The corresponding pose information is used to correct the position of the micro inertial navigation system. The simulation platform can be used for experimental research and simulation display of intelligent vehicle collaboration in a vehicle-vehicle-road network environment. This platform uses the embedded system carried by the smart car to directly control the car after processing the positioning information of the car, which saves communication time.

The invention relates to a transportation simulation method for onshore wind power large product transportation. The transportation simulation method comprises the following steps that 1, an air bag simulator with the proportion and size same as that of the wind power large product equipment is designed, that is to say, the air bag simulator is designed according to the true proportion of 1:1; 2,the air bag simulator is filled with gas and fixed to the top of a vehicle, a person drives the vehicle to pass a bend, if the traffic problem is encountered, recording is conducted rapidly, and the road reconstruction scheme is judged, wherein the scheme comprises the step of widening an existing road, or cutting part of mountain blocking traffic, or removing line barriers above the road or removing power line poles and communication rods on the two sides of the road; 3, gas in an air bag of the simulator is discharged, so that the vehicle passes the bend having problems, the air bag simulator is filled up with gas rapidly and then fixed to the top of the vehicle, and the vehicle continues to move forwards till encountering the next bend with problems, by that analogy, the bends with problems are troubleshot one by one, and road survey tasks of all road sections is completed; the simulator is the air bag simulator, and the simulator is provided with a quick charge pump and a simulatorfixing frame fixed to the vehicle.

The invention discloses an electronic multi-scattering-angle sampling method based on acceptance-rejection sampling. The method comprises the following steps: (1) constructing a small angle similar distribution function FSA (theta) of multiple scattering angles theta; (2) calculating the maximum value fmax of the quotient f (theta) of theoretical distribution functions FMS (theta) and FSA (theta) of the multiple scattering angles theta; (3) directly sampling the multiple scattering angles theta sample according to FSA (theta); and (4) calculating f (theta sample), sampling a random number zeta in the range of [0, 1], if zeta less than f (theta sample) / fmax, receiving theta sample, and if zeta is not less than f (theta sample) / fmax, returning to the step (3). The multiple scattering angles of transportation of electrons in a medium can be sampled rapidly and accurately, the electronic Monte Carlo transportation simulation efficiency is improved, and the method can be widely applied to the field of radiation transportation simulation, the field of Monte Carlo particle transportation simulation and the like.

The invention provides a device in-orbit single event upset rate predicating method based on a composite sensitive volume model. The method includes: acquiring charge deposition borne by a device on an actual flight orbit by means of event transportation simulation; combining a single event effect simulation means of a device logic unit to acquire sensitive parameters of the device logic unit, establish the composite sensitive volume model, and describe incident event decomposition charge collection situation; after sample event upset of the logic unit is obtained, adopting a weighted statistic method to obtain a device in-orbit upset rate prediction result. Accuracy in in-orbit upset rate prediction of space navigation components and particularly of high-integration-level small-feature-size deep submicron devices is improved.

The invention discloses a fracturing proppant transportation simulation experiment method for real-time variable sand ratio, comprising the following steps: (1) measuring the bulk density ρ of the proppant t and apparent density ρ s ; (2) Set the value C of the initial sand ratio 1 ; (3) Set the fracturing fluid volume flow rate V f (4) Calculate the mass flow rate W of the required proppant by the volume flow rate of the fracturing fluid and the given sand ratio p , according to W p Calculate the servo motor speed n; (5) According to the determined fracturing fluid volume flow V f Pump proppant and fracturing fluid into the sand mixing cylinder at the same time as the speed n of the servo motor. When the liquid in the sand mixing cylinder reaches the high water level limit, stop pumping the fracturing fluid and proppant, open the sand mixing fluid outlet of the sand mixing cylinder, The sand mixing fluid is injected into the simulated fracture; when the liquid in the sand mixing cylinder reaches the limit of the low water level, the fracturing fluid and proppant are pumped into the sand mixing cylinder; (6) Change the value of the sand ratio and repeat steps (3) to (5 ), to achieve the purpose of changing the sand ratio in real time in the fracturing proppant delivery simulation experiment.

The invention discloses a simulated transportation simulation system, comprising: a processing unit, a 3D model unit respectively communicating with the processing unit, an input unit and a storage unit. The 3D model unit is used to import the 3D model of the blister plate and the display module, and calculate the collision displacement L and the collision contact area S according to the size in the model; the input unit includes: the simulation environment selection module and the display module parameter setting module. According to the simulation environment input by the simulation environment selection module, the preset initial speed and collision time and the collision displacement L calculated by the 3D model unit are called from the storage module, and the acceleration is calculated; the display module input by the module is set according to the module parameters. The mass, combined with the formula to calculate the impact force, combined with the collision contact area given by the 3D model unit, calculated the force per unit area according to the formula, the processing unit called the unit area resistance from the storage unit according to the module structure category, and Through the comparison, it can be concluded whether the design of the blister tray is reasonable.