49 results about "Trajectory method" patented technology

A ballistic trajectory method for a golf ball is disclosed wherein a ballistic trajectory of a golf ball having a plurality of dimples formed on the surface thereof when the golf ball is hit to fly at an arbitrary number of rotations and an arbitrary initial speed can be estimated and ballistic trajectory and flight characteristics of the golf ball can be evaluated without depending upon experimental evaluation which is based on an actual model thereby to allow a golf ball to be developed efficiently. The ballistic trajectory of the golf ball when the golf ball is hit to fly is estimated by successively calculating the flight distance and the height of the ball after every lapse of a very short period of time after the ball is hit to fly until it drops to the ground making use of arithmetic operation by a computer.

The invention discloses a method for recognizing behaviors in videos on basis of visual-semantic features. The method comprises the following steps of: firstly extracting short-term spatial-temporal visual features by utilizing a three-dimensional convolutional neural network, so as to avoid the high calculation complexity caused by a light stream or intensive trajectory method; extracting semantic and spatial position information of a person and an object by utilizing a convolutional neural network-based object detector, constructing person-object spatial position features, fusing the person-object spatial position features with the spatial-temporal visual features, and improving the recognition correctness for interaction behaviors in a video by utilizing extra semantic information; andfinally, on the basis of the extracted short-term spatial-temporal visual features with universality, extracting specific long-term behavior features through a recurrent neural network so as to improve the behavior recognition correctness. The method is capable of solving the technical problem that existing video-oriented behavior recognition methods are high in calculation complexity and low in behavior recognition correctness and cannot extract long-term behavior features which run through the whole video time dimensionality.

The invention discloses an automatic parallel parking path planning method based on two sections of second-order Bezier curves. The method comprises the steps of obtaining target parking space information to determine a parking target position and establishing a global coordinate system by taking the parking target position as an original point; constructing a parking trajectory segmentation judgment model to determine the number of planned trajectory segments, planning the end position range of the first section of trajectory, determining the start point, the end point and the control point of each section of planned trajectory, performing path planning by using a second-order Bezier curve, performing monitoring at set intervals, and adjusting the planned trajectory by using a dynamic adjustment planning trajectory method. According to the method, the requirement for the initial pose of the to-be-parked vehicle is lowered, and the environmental adaptability of the path planning methodis improved; the vehicle can be driven into the planned area manually through simple adjustment, so that the cost is reduced, and the method can be applied to medium and low-grade vehicles; control points of parking trajectory planning are easy to determine, a trajectory generation algorithm is simple, and the path curvature is continuous. The correction difficulty of the track error is reduced,and the obstacle avoidance performance and parking efficiency of the vehicle are improved.

Methods are provided for automatically analyzing and understanding activities and interactions. One method comprises receiving at least location information for one or more individual objects in a scene at a given time; applying at least one machine learning or artificial intelligence technique to automatically learn an informative representation of location trajectory data for each object; and identifying and analyzing individual and group activities in the scene based on the trajectory data. Another method comprises receiving at least location information for one or more individual objects in a scene at a given time; receiving visual information about the scene and at least one individual object in the scene; applying at least one machine learning or artificial intelligence technique to automatically learn an informative representation of location trajectory data, and to automatically learn an informative representation of visual appearance data; and combining the location trajectory and visual appearance data.

Methods and arrangements for measuring similarity with respect to moving object trajectories. First and second moving object trajectories are input, each trajectory being defined by at least two spatial dimensions and a temporal dimension. At least one segment is defined with respect to each trajectory, each segment being defined between two defining points. At least one segment from the first trajectory is matched with at least one segment from the second trajectory. A spatial distance and temporal distance are each computed between the at least one segment from the first trajectory and the at least one segment from the second trajectory. The spatial distance and temporal distance are combined to provide a measure of a spatio-temporal distance between the at least one segment from the first trajectory and the at least one segment from the second trajectory. Other variants and embodiments are broadly contemplated herein.

The invention discloses a novel online fault diagnosis method for a 110kV XLPE cross interconnection cable, namely a trajectory method. According to the method disclosed by the invention, cable metal sheath grounding wire loop current and operating voltage parameters are acquired through an online monitoring system, the parameters are transmitted to a computer, and a trajectory diagram integrating the two types of parameters in the same time period is constructed. Any fault corresponds to a different trajectory diagram, and differences between the trajectory diagram and normal conditions are analyzed and compared by using digital image processing technologies so as to carry out fault diagnosis accurately. The fault diagnosis method disclosed by the invention can overcome deficiencies of a traditional online monitoring and fault diagnosis method, is higher in accuracy and lower in cost, can realize real-time diagnosis, and can form a historical fault trajectory database.

The invention relates to a double-ring guidance method of skip re-entry, and belongs to the field of the guidance of the re-entry of aircrafts. According to the double-ring guidance method disclosed by the invention, the control precision of the guidance method to terminal distribution is improved by utilizing the prediction-correction executed by slow guidance tasks, and the problem that the control demand of high precision of skip re-entry is difficult to satisfy by only using the standard trajectory method is solved. According to the double-ring guidance method disclosed by the invention, the problem that the control precision of fall points is reduced by only using a prediction guidance method after the navigation precision deteriorates under large dynamic conditions is solved by utilizing a standard trajectory tracking method executed by fast guidance tasks. The prediction-correction executed by slow guidance in the double-ring guidance scheme disclosed by the invention solves the problem of the control precision of the secondary re-entry section under the conditions of initial large distribution.

Methods and systems for calculating electron or ion dynamics using spin-dependent quantum trajectories are disclosed. According to one exemplary embodiment of the present invention, electron or ion dynamics are obtained by solving a set of equations for electrons' motion using spin-dependent quantum trajectories calculated from electron current with one equation for each electron in the atomic structure of a material of interest. The set of equations is time-dependent Schrödinger or Dirac equations for the nonrelativistic and relativistic regime, respectively. The electron current contains a set of spin-dependent terms that guarantee Fermi-Dirac statistics are obeyed. Steady state solution of the set of equations for electrons' motion is a set of wave functions in a three-dimensional space and in time. The spin-dependent quantum trajectories for each of the electrons are updated at each solution cycle, and therefore, mean-field approximation is avoided.

The invention discloses a Lamb wave damage positioning method based on the elliptic probability and Bayesian estimation. The method comprises the following steps: S1, according to an elliptic trajectory method and a probabilistic damage reconstruction method, carrying out imaging and positioning on a damage by combining Bayesian estimation with an arrival time feature value and a correlation coefficient feature value; S2, on the basis of the elliptical trajectory method and the probabilistic damage reconstruction method, carrying out advantage complementing on non-linear path detection of theelliptical trajectory method and linear path detection of the probability damage reconstruction; and S3, constructing a likelihood function based on the elliptic trajectory method of the arrival timefeature value, constructing prior information based on a probabilistic damage reconstruction method of the correlation coefficient feature value, and carrying out damage positioning by posterior distribution of the position parameters. Therefore, problems that the sensitivity of the damage detection of the non-direct path and direct path can not be considered simultaneously because of many sensors, the uncertainty of damage location is high, and the robustness of positioning is low in the prior art are solved.

The invention discloses a support vector regression machine fusion-based expressway road section mean velocity estimation method. The method includes the following steps that: 1) an expressway to be researched is selected, and basic data are obtained; 2) a road section mean velocity is obtained through using a trajectory method-based correction algorithm and according to fee charging data; 3) passenger service vehicles and hazardous article transport vehicles of which the single operating mileage exceeds 800 kilometers are adopted as floating vehicles, a road section mean velocity is obtained through using a speed-time integral model and a weighted average method; and 4) a support vector regression machine fusion algorithm is adopted to fuse the two road section mean velocities, so that a support vector regression machine fusion-based expressway road section mean velocity can be obtained. According to the support vector regression machine fusion-based expressway road section mean velocity estimation method of the invention, expressway road section fee charging data and Beidou satellite positioning system data about the passenger service vehicles and hazardous article transport vehicles of which the single operating mileage exceeds 800 kilometers are combined, the fused road section mean velocity is obtained through the support vector regression machine method, and therefore, the accuracy of velocity estimation is improved, the daily monitoring and emergency disposal of expressway managers can be benefitted, and the operational efficiency of expressways can be effectively improved.

In a frequency spectrum analyzer (2) which receives a modulation signal previously measures the frequency (F). A synchronous detection frequency (B) is determined on the basis of the frequency (F). An adder (7) obtains the difference (G) between the synchronous detection frequency (B) and the reference frequency (C). From an I signal and a Q signal which are obtained by performing synchronous detection by using the synchronous detection frequency (B), a frequency error detector (6) obtains a frequency error (E) by the phase trajectory method. An adder (8) adds the difference (G) and the frequency error (E) to obtain a frequency error.

The invention discloses a pollution tracing method and device. The method comprises the following steps: inputting air quality forecast data into an air mass trajectory tracing model, and calculating to obtain backward diffusion trajectories of a point location selected at a preset moment at different heights after a preset duration; extracting longitude and latitude data sets of all heights on the backward diffusion trajectory, and drawing trajectory lines according to all the heights and the corresponding longitude and latitude data sets; and according to the emission height and position information of each pollution source obtained by the pollution source emission list and/or the pollution source general survey, screening out the pollution source of which the distance from the drawn trajectory is smaller than a preset length, and obtaining the pollution source emission information around the trajectory. The device comprises a diffusion track calculation unit, a track line drawing unit and a pollution source screening unit. According to the method and the device, respective advantages of a backward trajectory method and a pollution source information method are combined, results are associated, pollution source tracing results are further finely and scientifically focused, and guidance and direction are provided for subsequent pollution prevention and control work.

Methods, apparatus and systems for an exact filtered back projection process for circle-plus trajectories, which consist of two components: C and L. The first component C, is analogous to a circle in the traditional circle-plus trajectories, is any closed (not necessarily planar) continuous curve. The second component L is almost any continuous curve. The only condition is that L starts below C and ends above C. The process does not depend on the global properties of L. When the source is located on L, one needs to know only how C projects onto the corresponding detector and the properties of L in the immediate neighborhood of the source position. The present invention is especially convenient for the traditional circle-plus trajectories, which are implemented using a gantry and moving table by obtaining a universal FBP algorithm, which is independent of table movement during the scan as long as the condition on L is satisfied.

Methods and systems are provided for monitoring conformance of an aircraft to an actual and predicted 4-dimensional (4D) trajectory with respect to a reference business trajectory (RBT). First, a flight plan for the aircraft is acquired from an onboard flight management system (FMS) computer. A predicted flight trajectory is generated based on the latitude, longitude, altitude, speed and time of the flight plan for the aircraft. An onboard trajectory conformance monitor that is independent of the FMS computer, monitors the present flight trajectory of the aircraft and anticipates any actual or future deviations from the RBT. The trajectory conformance monitor will generate an advisory of any actual or anticipated deviations from the RBT.

The invention relates to a combined high-altitude wind detection method. According to the method, positioning data is selected through a GNSS (Global Navigation Satellite System), the position of a sonde is acquired in real time, high-altitude wind speed measurement, wind direction and wind profile calculation and measurement data processing are conducted on the continuously measured position, and calculating is conducted to obtain high-altitude wind by utilizing a trajectory method; a GNSS navigation positioning module adopts a multi-mode navigation positioning mode, receives a navigation signal sent by a Beidou system, and outputs GNSS positioning data after optimization processing; the navigation parameters and sounding measurement information are transmitted to a sonde mainboard, the sonde mainboard completes data quality processing, signal sampling transformation and data stream generation of meteorological element values and sonde positioning data information through an input module and a gain amplification module, parameters such as a speedometer in an INS navigation positioning module are processed before and after a GNSS, the INS navigation parameters in the missing measurement time period are corrected, and positioning data in the GNSS missing measurement time period is output after processing.

The invention provides an optimal time trajectory planning method for a mechanical arm. According to the method, under the condition that multiple constraint conditions such as the speed, the acceleration and the jump value of the mechanical arm are considered, the inertia weight and the learning factor in a particle swarm are improved, and the defect that the particle swarm is prone to convergence, so that a local optimal solution is obtained is overcome. Meanwhile, a 3-5-3 polynomial interpolation trajectory method is adopted, so that the algorithm is simple in structure, parameters are easy to adjust, and the defects that the polynomial is high in order, has no convex hull property and the like are overcome. According to the optimal time trajectory planning method, the particle swarm optimization is improved, so that the operation time of the mechanical arm is shortened, and smooth and stable joint position, speed and acceleration curves are obtained.