58results about How to "Reduce tracking time" patented technology

A mobile radio communication system which does not need an omnidirectional channel for both a base station and a mobile station to track each other and uses only a narrow beam channel and can reduce a tracking time than before for an adjacent base station and a mobile station to search each other while a visiting area base station and the mobile station are communicating in the overlapped area. The base station and the mobile station comprise a unit for transmitting and receiving in forward or reverse channel, in different frequency, in different tracking channel using a narrow beam. Both the mobile station and the visiting area base station search the location each other, and after searched, they assign the frequency and the beam used in the tracking channel. At the same time, by comprising a searching slot in an information channel to search an adjacent base station while communicating with the visiting area base station, a tracking of other adjacent base station can be performed.

The invention discloses an adaptive ORB object tracking method. The adaptive ORB object tracking method adds FAST characteristic direction information in order to solve the problem that the FAST characteristic has no direction; a BRIEF characteristic descriptor based on pixel point binary digit comparison is adopted in a characteristic point description portion; the defects that the BRIEF descriptor is sensitive to the image noise and has no rotation invariance are improved; and compared with an SIFT algorithm, the ORB algorithm has the rotation invariance and noise resistance, and the operation speed of the ORB algorithm is higher than that of the SIFT algorithm by two orders of magnitude. The adaptive ORB object tracking method fully utilizes the characteristic of the ORB algorithm, performs further improvement on the PRB algorithm, brings forward the ORB algorithm on the basis of that the improvement, further improves the operation speed and the tracking accuracy, and better meets the demand for the real-time tracking.

The invention discloses a GPS software receiver baseband signal real-time tracking method based on code memory, wherein the method is based on prestored and fine-adjusted local C/A code to perform binary system storage and performs table lookup and invocation to solve the problem that real-time code which wastes time are generated in GPS software receiver tracking signal time. In GPS software receiver tracking loop, the process that local C/A code is generated through minute adjustment is longest in the three longest processes, namely generation of fine-adjusted local C/A code, generation of local carrier wave and related integration and the time for generating fine-adjusted local C/A code is nearly half of the entire signal tracking and processing time. The invention uses the binary data of prestored and fine-adjusted local C/A code and directly loads data to perform table lookup and call data so that the fine-adjusted early code and late code can not be generated in every tracking cycle, the time wasted by real-time code can be saved, the time for the generation of codes in tracking cycle is saved and the tracking speed doubles.

The invention relates to a finite-time neural network control method of a motor-driven single-connection rod manipulator. The method comprises steps of (1) establishing a mathematical model of the motor-driven single-connection rod manipulator and an actuator nonlinear module with a dead zone and input saturation limitations; (2) determining a control target, wherein system output is capable of tracking reference output of the system within the infinite time, and the system output is kept in a limited range; (3) designing an infinite time neural network control law and achieving a control target; and (4) designing a barrier Lyapunov candidate function and analyzing stability of a closed loop system, and according to the stability analysis of the Lyapunov candidate function, determining control parameters of the designed control law. According to the invention, by considering limitation factors of input saturation limitations, the dead zone, output limitations and system indeterminancy,the control method can be well applied in an actual system. In addition, infinite-time track tracking can be achieved; tracking time is reduced; and robustness and control precision of the system areimproved.

The invention relates to a video target tracking method based on compressive sensing. The video target tracking method comprises the steps of firstly, generating a sparse projection matrix according to the compressive sensing theory and performing sparse projection dimensionality reduction on positive and negative samples obtained by sampling to create a Bayes classifier, and when next frame of frame comes, performing sampling around the obtained target position of a prior frame, obtaining the most possible target position by classifying by use of the classifier, updating the target position and updating the parameters of the classifier. The video target tracking method based on compressive sensing is capable of effectively overcoming the problem of unstable tracking caused by target characteristic change, and capable of effectively reducing the computation complexity and shortening the tracking time by compressing high-dimensional information into low-dimensional information according to the compressive sensing theory.

Disclosed is a technique for accurately tracking a tracking target object. A disparity map image in which the disparity of each pixel of an object is shown is generated from a three-dimensional object image. A detection range is determined such that an object disposed on the front side of a pedestrian, which is a tracking target object, in the depth direction is excluded from the generated disparity map image. The pedestrian, which is a tracking target object, is detected in the determined detection range. In this way, it is possible to prevent a bike driver disposed on the front side of the pedestrian in the depth direction from being tracked.

The invention provides a maximum power tracking control method and system for a photovoltaic array. The tracking control method comprises the following steps: firstly, determining a relationship between an output voltage and an output current of the photovoltaic array by utilizing a photovoltaic effect according to acquired actual light intensity and actual temperature; secondly, based on the relationship between the output voltage and the output current, tracking the maximum power point of the photovoltaic array by adopting an adaptive weight particle swarm algorithm; and finally, adjusting the transformation ratio of a DC-DC converter disposed between the photovoltaic array and the load according to the output voltage of the maximum power point, and enabling the photovoltaic array to work at the maximum power point. According to the method, the particle swarm algorithm with the self-adaptive weight is used for tracking the maximum power point of the photovoltaic array, the power loss caused by falling into local optimum in the tracking process is avoided, the tracking of the first peak power through the particle swarm algorithm in the initialization stage is not needed, and the tracking time of the maximum power point is shortened.

The invention relates to a fixed-time predetermined performance recurrent neural network mechanical arm control method. The method comprises the steps that (1) a mathematical model of a mechanical armdriven by a direct-current motor is established, and an actuator model with an unknown nonlinear dead zone is established; (2) system reference output is determined, and a performance function, whicha tracking error needs to meet, is designed; (3) a fixed-time predetermined performance recurrent neural network controller, a neural network weight update law and a fixed-time differentiator are designed so that system output can track a reference output trajectory in fixed time, and meanwhile the system tracking error is limited within a performance boundary range designated in advance; and (4)stability analysis is performed on a control system, and controller parameters are determined according to the stability analysis result. Through the method, fixed-time predetermined performance trajectory tracking can be realized, so that tracking time is shortened, control precision is improved, and transient performance and steady performance of the system in the control process are guaranteed.

The invention discloses a ray tracing method and system based on NURBS, and mainly solves the problems of low speed and low precision of an existing ray tracing method. The scheme is as follows: the method comprises the following steps of 1, representing a curved surface as a plurality of curved surface elements according to the curved surface node distance information; 2, excluding part of curvedsurface elements without an intersection by utilizing axis arrangement bounding boxes of the curved surface elements; 3, further excluding the curved surface elements without the intersection by utilizing a triangular surface element control network; 4, taking the intersections of the ray and the residual curved surface elements by utilizing an extreme value search iteration method; and 5, tracking the ray by utilizing a geometrical relationship and a Fresnel law to form recursion in order to trace a ray trajectory. According to the method and the system, more curved surface elements withoutthe intersection are excluded by the axis arrangement bounding boxes and the triangular surface element control network, so that the ray tracing time is shortened; the ray-curved surface intersectionis solved through the extreme value search iteration, so that the precision of the intersection is improved; and the method and the system can be used for rapidly and accurately computing the radar scattering cross section area of a surface curved target.

The invention relates to a photovoltaic multi-peak power point tracking method based on a territory particle swarm. The method comprises the following steps: 1) adjusting a duty ratio of a PWM as 0 toobtain output voltage of a Boost circuit; 2) setting the number of the particle swarm; 3) computing an adaptive value of each particle, re-judging and selecting a global optimal particle and the global optimal particle territory according to the obtained adaptive values; 4) determining a maximum value estimation range in the particle territory; 5) judging whether the condition that the maximum value estimation range contains the adaptive value of the global optimal particle is tenable; 6) judging whether the condition that the maximum distance dmax between the particles is less than 0.02Uocaris tenable; 7) computing each particle adaptive value, re-judging and selecting the global optimal particle; 8) judging whether the condition that the maximum distance dmax between the particles is less than 0.01Uocar is tenable; and 9) maintaining the output voltage as the voltage of the obtained global optimal particle location, and judging whether the environment changes suddenly.

The embodiment of the invention provides a position tracking method and a device applied to a portable station. Through a pre-tracking model, an antenna position is judged and a satellite theoretical position is solved; a coarse tracking module carries out tracking in a dot matrix mode for searching for sampling points whose satellite beacon level values are larger than a tracking threshold; and a fine tracking module carries out tracking in a cross dot matrix mode for searching for the maximal satellite beacon level point. By adopting the method and the device provided by the embodiment of the invention, an open loop control method is adopted, in comparison with a closed loop control method, elements such as a position feedback element and an encoder can be saved, the space of the portable device can be saved, and the weight of the portable device is reduced. As the elements in the portable station are reduced, reliability of the portable station is enhanced, maintenance is easy, and stability is high.

An attack path detection method, attack path detection system and non-transitory computer-readable medium are provided in this disclosure. The attack path detection method includes the following operations: establishing a connecting relationship among a plurality of hosts according to a host log set to generate a host association graph; labeling at least one host with an abnormal condition on the host association graph; calculating a risk value corresponding to each of the plurality of hosts; in a host without the abnormal condition, determining whether the risk value corresponding to the host without the abnormal condition is greater than a first threshold, and utilizing a host with the risk value greater than the first threshold as a high-risk host; and searching at least one host attach path from the high-risk host and the at least one host with the abnormal condition according to the connecting relationship of the host association graph.

A motion simulator includes a stationary frame, a movable frame pivotally connected with the stationary frame, an operating chamber formed at a lower side of one end of the movable frame, a first actuator for pivoting the movable frame, and a second actuator arranged between the operating chamber and the movable frame, for rotating the operating chamber in forward and backward directions with respect to the movable frame.