127 results about "Shortest path search" patented technology

A method for finding shortest paths is disclosed which uses a piecewise linear cost model to guide the search of through a compact tile graph and to ensure that a shortest path may always be found in a computationally effective manner. Cost function propagation from tile segment to tile segment is used to search for a target location from a source location through a region, and the shortest path is found through tracing backwards using the cost functions calculated during the searching. Linear minimal convolution is used to facilitate the cost function propagation.

"Midway" is a new method to search for a shortest path from a single source node to a single destination node in a two dimensional computer network. It is similar to Dijkstra shortest path search algorithm in the way to build a shortest path tree, but it is different from Dijkstra algorithm in the following points. Instead of starting from the source node and searching all the way through to the destination node as what Dijkstra algorithm does, Midway runs shortest path search from both ends (i.e. source and destination) simultaneously or alternatively, until a shortest path from one end meets a shortest path from the other end on midway. Algorithms are designed to run shortest path search from both ends, and conditions other than those used by Dijkstra are defined to determine when the search should terminate. It has been verified that the new search method takes much less overhead and time than Dijkstra to find a shortest path.

This invention belongs to VLSI physical design technique field and relates to one computer aid design method facing analogue circuit board graph, which is characterized by the following: totally according to analogue integration circuit multi-line wide binding for design to satisfy analogue circuit load current status complexity requirement. This invention comprises shortest path index method with multiple line width binding conditions and adopts starting index method to realize automatic line distribution process on network mode.

Provided is a machine learning strategy based distance preferred optimal path selection method (OPABRL). A local path is planned according to path direction, width, curvature road intersect and faultdetail information in practical application of an intelligent driving vehicle. A reinforced learning algorithm is known and learned to design the prior knowledge based optimal path selection method ofthe reinforced learning strategy, the searching direction for the shortest path is set in the program, and the shortest path searching process is simplified. The path optimization method can be usedto help different types of intelligent driving vehicles plan an optimal path in the traffic network with height, width and weight limits or in accident / jamming conditions smoothly. According to simulation and scene experiments, the method of the invention is higher in efficiency and practicality compared with existing ACO, GA, ANNs and PSO algorithms.

The invention discloses a method and device for searching the shortest path of a road network. The method comprises the following steps of dividing the road network into a plurality of sub-networks to generate the road network with a tree structure; calculating the shortest path between boundary nodes of the sub-networks at the same layer; inputting an enquiry point and a target point; according to the shortest path, implementing a dynamic programming algorithm to obtain the initial shortest path between the enquiry point and the target point; and supplementing the initial shortest path to obtain the complete shortest path between the enquiry point and the target point. According to the method, the road network is divided into the plurality of sub-networks so as to generate the road network with the tree structure, and the shortest distance between the boundary nodes of the sub-networks at the same layer is calculated, so that the shortest path between the enquiry point and the target point can be rapidly obtained when the enquiry point and the target point are input; the method and the device not only are high in efficiency, but also well meet the requirement of real-time property.

The invention discloses a shortest path induction method based on real road network features and dynamic travel time. The method includes the steps that firstly, the real road network features are taken into account, and a road network abstract graph is obtained based on intersection turning restriction information and link traffic flow direction maldistribution; secondly, the dynamic travel time of a road section is predicted by regarding real-time travel time and historical travel time as factors, and road section traffic impedance is calculated and serves as road section weight of an abstract road network according to the predicted dynamic travel time; finally, the real-time shortest path is obtained through the shortest path search algorithm. The method overcomes the defects that an existing road network abstract model can not reflect the real road network features (the intersection turning restriction information and the link traffic flow direction maldistribution) and an existing shortest path induction method based on static traffic information can not respond to accidental, random and dynamic traffic events (such as traffic jams, temporary control and traffic accidents) in time and the other defects, and the induction path obtained through the method is better in real-time performance, more accurate and more effective.

The invention aims to provide a shortest route searching method based on a route and weight. The shortest route searching method comprises the following steps that (1) the length of route each road equals a value of a real distance dividing a weight value; (2) each road in a to-be-analyzed area is connected; (3) starting points and terminal points are connected to achieve connection lines, so a plurality of initial route polygons can be achieved; (4) the plurality of initial route polygons are combined to achieve a coated polygon; (5) with the connection lines as a border, a starting left route and a starting right route of the coated polygon can be achieved; (6) a shorter connection line is employed to replace a connection line of two points corresponding to the starting routes and search is orderly continued to achieved a new left route and a new right route; (7) if the new left route and the new right routes are overlapped, the overlapped part is sure to be the shortest route part; if the new left route and the new right route are not overlapped, a final left route and a final right route can be achieved; (8) middle polygons in the final left route and the final right route are combined to achieved a combined polygon; and (9) a public part of the new left and right routes is combined with an acquired result to achieve the final shortest route. The shortest route searching method based on route and weight has high searching efficiency and precision, and can be applied to current each space data processing software platforms.

The invention belongs to the technical field of an unmanned aerial vehicle, and discloses an unmanned aerial vehicle aerial photographed image splicing method based on a suture line. Through eliminating a shield over an overlapped area, a smallest communicating subarea with the suture line is solved. Furthermore the suture line is searched in the smallest communicating subarea in a shortest path searching mode through recursion backtrack, thereby realizing image splicing. An equidistance line neighborhood searching method is utilized for further reducing the smallest communicating subarea with the suture line, thereby reducing calculation complexity and improving algorithm efficiency. An experiment result proves a fact that the algorithm of the invention can effectively prove a local offset phenomenon in suture line fusion. The unmanned aerial vehicle aerial photographed image splicing method can acquire an accurate spliced image and improves splicing efficiency.

The invention discloses a search method for the shortest path passing through necessary vertices. The implementation steps are: (1) Construct a weighted directed graph that satisfies the path relationship; (2) Find the shortest path between the search starting point and each necessary vertex; (3) Determine whether the path exists; (4) If it exists , then use the necessary vertex as the new search starting point, and continue to search for the path; (5) if it does not exist, then go back to the previous necessary vertex, and select the next shortest path to continue searching; (6) search the last found necessary vertex to the destination The shortest path between vertices; (7) The path can be found by combining the shortest paths found between all necessary vertices. By comparing the present invention with the depth-first search method, the genetic method and the ant colony method through experiments, it can be found that the present invention has the advantages of fast solution speed, good stability and the like.

The invention relates to an urban subway dynamic passenger flow distribution method constructed on the basis of a time-space network. Based on a subway passenger flow demand and an aging characteristic of passenger travel cost, urban subway dynamic passenger flow constructed by the passenger travel time-space network is distributed. Based on a subway space network, train running timetable information is combined, subway physical stations are expanded in time and space and a minimum cost route among each station in the time-space network is obtained according to a shortest route search algorithm. According to the dynamic passenger flow distribution method, a user balance principle can be met so that a passenger travel time and space route is closer to an actual one.

The invention proposes a quick mosaic method for aviation images with high tilt rate and low overlapping rate. By utilizing the method, the robustness of registration of the images with high tilt rate and low overlapping rate can be improved, the mosaic error can be reduced, and the synthesis efficiency of a wide image can be enhanced. The method is implemented by the following technical scheme of firstly, calculating a position distribution relationship of the images by utilizing imaging assistance data of the aviation images, establishing an image position relationship matrix, and calculating a reference image; secondly, calculating overlapped regions between adjacent images on adjacent paths through an adjacent image path between a shortest path search image and the reference image, and extracting significant feature points of the overlapped regions; thirdly, normalizing the feature points or the regions into a vertex, constructing a multi-scale image by utilizing different adjacent distance point sets, and performing matching by applying image matching to calculate a spatial transformation matrix; and finally, calculating corresponding coordinates of synthesized image pixels in a source image by using the spatial transformation matrix, and calculating the pixel values of the synthesized image by using bilinear interpolation, thereby obtaining a final mosaic image.

The invention discloses a dynamic road network based hierarchy priority optimal path calculation method. The method includes a step 1 of performing hierarchy division on road networks according to road ranks and generating Voronoi maps corresponding to the different levels of road networks; a step 2 of performing path searching by adopting a multi-level search strategy and searching the body partand the branch part of the optimal path based on a shortest path searching method; a step 3 of generating the optimal path according to the body part and the branch part of the optimal path. Accordingto the invention, the driving time of automobiles on roads can be reduced substantially and change of traffic flow states in road networks can be responded. Further, a reliable real time solution canbe provided for path selection for travelling vehicles, so that adaptability and reliability of travel schemes can be enhanced.

The invention discloses an AGV shortest path planning method. The method comprises a step of setting a starting point and an ending point of an automated guided vehicle (AGV) based on a preset map coordinate system, wherein the map coordinate system includes a path node, a step of determining the direction of travel of the AGV according to a preset algorithm and determining marked nodes from the path node according to the direction of travel, and a step of generating a shortest path of the AGV according to the starting point, the marked nodes and the ending point. The invention also disclosesan AGV shortest path planning device and a computer-readable storage medium. The invention is suitable for the shortest path search of the AGV in a factory workshop, the calculation is simple, and thecomplexity is low.

The invention provides a real-time shortest path search algorithm in an interactive layout tool, belonging to the technical field of the integrated circuit layout design automation, which in particular relates to an interactive layout automatic routing algorithm which can search the shortest path between designated points or units on a published picture in real time. The invention adopts a non-grid routing model with level block management, is not required to pre-extract the layout, reduces the expense for model conversion at the same time of improving the routing flexibility, and improves the path search speed by using buffered data, thereby meeting the requirement in the real-time routing in a layout editor.

The invention discloses an intelligent scheduling system of unmanned conveyers in a workshop. The intelligent scheduling system of the unmanned conveyers in the workshop comprises at least two devices, i.e., a central control device and a sub-conveyer self-control device, wherein a wireless communication module is arranged between the central control device and the sub-conveyer self-control device; the central control device and a self-scheduling device of the central control device are controlled by a handheld terminal device, and the central control device comprises a man-machine interaction interface and a central alarming system, and uses a shortest route searching policy of the unmanned conveyers in the workshop; the sub-conveyer self-control device comprises relevant sensors; and the sub-conveyer self-control device comprises related sensors, and real-time fault detection modules and dual-controller communication modules are added into sub-conveyers, so that the real-time route modification and local emergency action control are realized so as to safely avoid moving barriers or pedestrains in the workshop, and prevent the influence of the temporary route modification to the constant work. With the adoption of an additionally arranged voice alarming system, the working security in the workshop is further ensured. Therefore, the intelligent scheduling system has the advantages of high intelligence, good real-time performance, low manufacturing and maintenance cost, and the like.

The invention provides a method for controlling system recovery based on network reconfiguration FDIR (Failure Detection, Isolation and Recovery). The method comprises the following steps of: recovering power supply to 75-90 percent of load of a system within a shortest period of time according to the practical running condition and recovery initial state of an electric network with a recovery target screening method, wherein during selection of recovery targets and determination of a recovery step, common problems require to be considered; in a system recovering process, achieving the major targets of supplying power to a power plant and a transformer station, decomposing the major targets into a series of relevant sub-targets via path search, feasibility verification, switch-on / off operation and the like and resolving respectively; performing synchronization operation, decomposing an island station to be synchronized serving as a target station into sub-targets such as path search, feasibility verification, switch-on / off operation and the like and resolving respectively; and establishing a shortest path search algorithm which combines breadth-first with depth-first by adopting a station-oriented level-by-level reasoning control strategy on the basis of an electric network structural model knowledge base so as to well solve the problems of huge search space and combination explosion.

The invention belongs to the technical field of trajectory calculation and particularly relates to a historical data-based missing path recovery method. The method comprises the steps of in a training stage, performing modeling on a trajectory by utilizing a Markov decision process model, and training model parameters according to historical trajectory data; and in an online query stage, calculating a transfer probability between roads according to a trained model, constructing a graph, assigning a weight of the edge by using a negative logarithm of the transfer probability, obtaining a path with a highest probability by using shortest path search in the graph, and recovering a missing part by using the path. According to the method, the reliability and accuracy of an algorithm also can be kept under a long-distance missing condition.

The invention provides a Boost Graph library-based K shortest path searching method and system. The Boost Graph library-based K shortest path searching method comprises the following steps of: expanding a K shortest path algorithm on the basis of a mature C++ Boost Graph library; optimally sequencing shortest paths to be selected by adopting a d-heap data structure; and developing multiple shortest routes by adopting an edge deviating manner. The Boost Graph library-based K shortest path searching method solves the practical difficulty in the k shortest path problem to a certain degree from the computer application angle, and the workload of practical design or development algorithm is greatly lightened. The Boost Graph library-based K shortest path searching system is a set of software and hardware system based on the method, integrates all invent contents of the method and can be directly used for searching the K shortest path before computation.

The invention belongs to the technical field of electronic information, and particularly relates to an automated container dock collaborative operation system and a shortest unloading path searching method. The system comprises a ZPMC automated container dock loading and unloading system, a loading and unloading system agent layer model, a management agent, an equipment agent and an information agent. According to the collaborative operation system, loading and unloading equipment is abstracted into intelligent agents with a series of behaviors and attributes, meanwhile, intelligent agents such as a ship agent, a storage yard agent, a task management agent and an equipment management agent are provided, layering construction is carried out according to agent functions, and subsystems achieve negotiation and cooperation through information sharing. The MAS-based automated container dock collaborative operation system further includes the shortest container loading and unloading path searching method.

The invention provides an overall image information synthetic method driven by a visual cognition model, which comprises the following steps: creating a image significance visual cognition model, and defining a column width selection driving energy function for the overall image information synthesis; structuring an overall image information composite image model, defining a node and computing the connecting side weight of the node; adopting the Dijkstra algorithm to search in the overall image information composite image model to enable the overall composite image significance visual cognition difference to reach the minimum clipping path; and selecting certain pixel column width in each frame of image in intensive video sequence images according to the minimum clipping path order, arranging the selected pixel column width according to sequence code, and synthesizing the pixel column width into overall composite image. According to the method, the function of visual cognition model of people on the overall scene picture synthesis can be fully expressed, synthesis flaw caused by multi-dimension mobile interference can be reasonably avoided, and key contents of wide large-scale scene can be effectively repeated.

A sub-path protection method of a single link fault in a wavelength division multiplex network belongs to the technical field of optical networking communication. The method comprises the following steps: (1) searching a path satisfying protection switching time restriction for each node pair as a working path in a network topology; and then searching a protective path satisfying protection switching time restriction and link separation for each working path; (2) mapping the network topology into a virtual topology; and (3) searching a virtual path for a reached service; and then searching a working path and a protective path with minimum resource consumption in each virtual link of the virtual path. The sub-path protection mechanism has the advantages of protection of resource sharing and protection of switching time restriction so as to improve resource utilization, reduce blockage rate, and effectively reduce networking time consumption, namely, the use times of the shortest path searching algorithm.

The invention discloses a minimal path searching method based on a quotient space overlying model, which comprises the following steps: constructing a quotient space overlying model composed of all maximal complete-subgraphs of all levels of quotient space overlay networks in a hierarchical quotient space overlay network chain and node information thereof in an initial network, acquiring the hierarchical numbers of a starting point and a terminal point for searing in corresponding positions in maximal complete-subgraphs of all levels of quotient space overlay networks, comparing the hierarchical numbers thereof, searching paths from a quotient space with a finer granularity, and searching from quotient space overlay networks with gradually finer granularity until from a quotient space overlay network with the finest granularity to obtain the minimal path between two nodes, so as to solve the minimal path rapid searching problem in an undirected and unweighted network and can obtain multiple minimal paths in the network at the same time. The method can obtain the minimal paths between two nodes by comprehensive utilization of network resources, so as to solve the problems of the minimal transfer times of a passenger in traffic networks, efficient utilization of energy in electric networks, rapid fault path detection, etc.

The present invention provides a method for searching for the shortest path between two points in the improved Dijkstra algorithm, comprising the following steps: 1) introducing an adjacency matrix in the graph theory and assisting the search process by using an adjacency matrix, that is, after determining the shortest distance from one vertex to the starting vertex each time, finding a column wherein the row element is 1 corresponding to the vertex in the adjacency matrix; and 2) calculating and analyzing only the vertex distance value corresponding to the column with the element 1 in step 1), and effectively reducing the calculation amount of the search process. The method for path analysis based on the adjacency matrix avoids useless calculation processes of disjoint nodes, effectively reduces the amount of computation, and ensures the shortest search path.

A method for finding shortest paths is disclosed which uses a piecewise linear cost model to guide the search of through a compact tile graph and to ensure that a shortest path may always be found in a computationally effective manner. Cost function propagation from tile segment to tile segment is used to search for a target location from a source location through a region, and the shortest path is found through tracing backwards using the cost functions calculated during the searching. Linear minimal convolution is used to facilitate the cost function propagation.

The invention relates to a public transportation information service method using a mobile communication terminal, which combines the current position, the nearest bus station or subway station, and the bus route and subway route to inform public transportation users that they will arrive at the desired destination in the shortest time public transport information. The mobile communication terminal of the present invention includes: a first database for storing information about public transportation routes; a second database for storing information about buildings or roads displayed on a map for leading the way; a current position detection unit for detecting information about Information on the current location of the terminal; the control unit refers to the first and second databases, searches for a route from the current user's location to the destination, and outputs the corresponding search information on the screen. The present invention is realized through the following steps: a step of detecting the user's current location; a step of searching for the shortest path from the current location to the user's desired destination by public transportation; and a step of displaying the above-mentioned searched shortest path.

The invention discloses a sound ray tracing method of a fiber reinforced plastic composite material laminated plate, and belongs to the technical field of composite material ultrasonic inspection. The method comprises the following steps: taking a single ply as a unit to partition a computational domain, and utilizing an elastic stiffness matrix and the rotation transformation of the elastic stiffness matrix to quantitatively descript the elastic characteristic space distribution of FRP (Fiber Reinforced Plastic) composite materials; combining with a Christoffel equation to solve to independently obtain the function relational expressions, which are about a propagation direction angle, of quasi-longitudinal wave group speed values corresponding to different fiber orientation lays; and carrying out computational domain meshing, utilizing a Dijkstra shortest path search algorithm to search nodes through which ultrasonic wave passes when the ultrasonic wave is transmitted to a target point from a source point, and calculating corresponding sonic time. The method can realize the quick and accurate calculation of an ultrasonic wave propagation path and sonic time in the FRP composite material which has a multilayer structure, elastic anisotropy and different fiber laying sequences, and support is provided for researching ultrasonic wave propagation behaviors, optimizing a detection parameter and improving ultrasonic imaging quality and accuracy.

An embodiment of the invention provides a method and a device for segmenting a text image and belongs to the field image processing. The method includes: binarizing the text image to acquire a binarized image, wherein the text image includes multiple text lines; acquiring a communication area, meeting preset threshold conditions, in the binarized image; acquiring character nodes of the communication area to build a digraph; performing shortest path search on the digraph to acquire a character node sequence, belong to each text line, in the text image; segmenting the text image according to the acquired character node sequence. Compared with existing text line segmenting methods, the method and the device have the advantage that accuracy in line segmenting of text images having inclined and distorted text lines is improved effectively.

System, method and computer program product for combined scheduling of two different slab sequences by a rational technique. A two-dimensional grid graph having a direct slab sequence as a first dimension and an inventory slab sequence as a second dimension is prepared by processing of a computer as a data structure represented on a memory or a hard disk drive of the computer. A processing program of the computer generates two child nodes corresponding to a direct slab and an inventory slab, in each node of the two-dimensional graph according to a predetermined algorithm. By defining an appropriate weighting function, the processing program of the computer weights edges between nodes in the two-dimensional grid graph. After forming the weighted graph on a storage device of the computer such as the memory or the hard disk drive, the processing program of the computer calculates a path from a start point to an end point as a shortest path search problem.

The invention discloses an urban road network time varying K shortest path search algorithm capable of considering turn delays. The algorithm comprises the following steps that: on the basis of obtaining the intersection turn delays of continuous equal time intervals and a road section stroke time data sequence, combining with an extended network method to obtain time varying impedance between intersection boundary lines in a network; adopting an A* algorithm to search a shortest path and stroke time from an appointed starting point boundary line to an end point boundary line; and furthermore, circularly adopting a connecting line deletion method and the A* algorithm to delete the shortest path under parts of connecting line conditions until search for the appointed K time varying shortest path is finished. By use of the time varying K shortest path search algorithm provided by the invention, the influence on path search by the time variation and the intersection delay of the urban road network impendence is simultaneously considered, a globally optimal result can be obtained at a high calculation speed, and the algorithm exhibits good maneuverability.