60 results about "Dijkstra's algorithm" patented technology

An agile digital communications network has a number of routers that serve as nodes in a mesh network communicating between a user device (e.g., computer, server, etc.) and a target device (e.g., disc storage cabinets, tape, jukebox, etc.). The routers operate on an open shortest path first protocol, each router having two or more interfaces or links to other routers. When a link connected to a router is down and is in the shortest path to another router identified in a communication packet, the packet is forwarded to the identified router on a precalculated alternate route that does not use the unavailable link. IP tunneling assures that routing loops do not occur and send the packet back to the router with the unavailable link because it would have been in the shortest path of an intermediate router. A tunneling technique is provided that maximizes the levels of encapsulation needed at two, regardless of the size or configuration of the network. An unavailable link is not broadcast immediately throughout the network, giving the link an opportunity to be restored before all of the routers are called on to recalculate the shortest paths and alternate paths. During a short interval following the discovery of an unavailable link, then, a router connected to that link is in a state identified as the Use Alternate Path state, and the link is repeatedly checked for availability. Each router calculates and stores the alternative paths to each other router after first calculating the shortest path to each other router. The alternate paths are pulled up and used when an unavailable link is detected. Dijkstra's algorithm is used to calculate the shortest paths. A new algorithm called the iterative dynamic Dijkstra's algorithm is used to calculate the alternative routes.

A path computation method includes defining photonic constraints associated with a network, wherein the photonic constraints include wavelength capability constraints at each node in the network, wavelength availability constraints at each node in the network, and nodal connectivity constraints of each node in the network, and performing a constrained path computation in the network using Dijkstra's algorithm on a graph model of the network with the photonic constraints considered therein. An optical network includes a plurality of interconnected nodes each including wavelength capability constraints, wavelength availability constraints, and nodal connectivity constraints, and a path computation element associated with the plurality of interconnected photonic nodes, wherein the path computation element is configured to perform a constrained path computation through the plurality of interconnected nodes using Dijkstra's algorithm on a graph model with the photonic constraints considered therein.

The invention provides an intelligent matching and route optimization-base carpooling method and system. The method includes the following steps that: a passenger travel information set and a vehicle state information set are acquired; spatial-temporal distances between passengers and vehicles are calculated, a passenger and vehicle matching candidate set is created according to the calculated spatial-temporal distances, the travel time of the passengers and the number of the passengers; an integer planning model is created, and passenger and vehicle matching results are obtained according to the created integer planning model; and based on the combination of the passenger and vehicle matching results and real-time traffic states, time-varying Dijkstra's algorithm or a time-varying A star algorithm is utilized to obtain optimal vehicle driving paths. According to the intelligent matching and route optimization-base carpooling method, dynamic traffic information is utilized to measure the spatial-temporal proximity of the travel demands of individuals; spatial-temporal locality is adopted to guide group intelligent carpooling matching; and dynamic vehicle paths with minimum cost are designed; and therefore, spatial-temporal precise matching of massive travel demand services and efficient path planning can be realized.

The invention discloses a parking path planning method for an automatic driving system of a parking lot. The method comprises the following steps: mathematical modeling is performed on the parking lotaccording to road network information in the parking lot; a corresponding node at a road intersection of the parking lot and each parking space is selected and numbered, and a corresponding matrix relationship is established; line information in a line information table is read, and the distance between a starting point and an ending point is taken as a weight value; a Dijkstra map is constructedon the basis of a node graph of a road network, and the optimal path is calculated with the Dijkstra algorithm. The optimal path from the starting point of the parking lot to the parking space can berapidly planned.

Embodiments provide systems and methods that find the quickest route between two locations on a graph with multi-edge constraints in a time and space efficient manner. In some embodiments, Dijkstra's algorithm is split into separate universes when a) a multiple-edge constraint is reached, and b) along each edge of a multi-edge constraint. In some embodiments, the split is performed for the purpose of finding the quickest (i.e. lowest weighted) route to the intersect ion(s) at the end of the constraints. These universes, in some embodiments, are merged or discarded when the intersection at the end of the constraint is found. Using these systems and methods, in some embodiments, the shortest path between two locations of a multi-edge constrained road network can be efficiently determined.

Embodiments provide systems and methods that find the quickest route between two locations on a graph with multi-edge constraints in a time and space efficient manner. In some embodiments, Dijkstra's algorithm is split into separate universes when a) a multiple-edge constraint is reached, and b) along each edge of a multi-edge constraint. In some embodiments, the split is performed for the purpose of finding the quickest (i.e. lowest weighted) route to the intersection(s) at the end of the constraints. These universes, in some embodiments, are merged or discarded when the intersection at the end of the constraint is found. Using these systems and methods, in some embodiments, the shortest path between two locations of a multi-edge constrained road network can be efficiently determined.

The invention relates to a minimum distance calculating method of a moving object in a restricted space, and belongs to the technical field of moving objects management in the computer spatial database. According to the minimum distance calculating method of a moving object in a restricted space, obstacles in an indoor space are modeled and a visible area of the moving object is calculated. By using a method of using boundary vertices of the moving object and the obstacle space to construct a maximum angular difference, an optimum vertex in the obstacle space is obtained, and the visible area is constructed. Based on this, in the invention, the visible area is used, and for different position relationships between the moving object and the visible area: for the moving object in the visible area, the distance is directly calculated by using an Euclidean distance calculating method; and for the moving object not in the visual area, the minimum distance between the moving object and a target object is obtained by using the Dijkstra's Algorithm and the method of constructing a weighted directed graph.

The present invention discloses a method for optimizing an OLSR protocol through multiple parameters, comprising: sampling a link signal-to-noise ratio and a link transmission rate according to a predetermined cycle; according to a range corresponding to the link signal-to-noise ratio obtained by sampling, correcting the link transmission rate to obtain a final link transmission rate; according to the final link transmission rate, acquiring a link overhead; according to the link overhead and a packet loss rate, calculating to obtain a total link overhead; and calculating to obtain routes of the entire network using the Dijkstra's Algorithm according to the total link overhead. The method can meet the requirements of timeliness, accuracy and effectiveness of link overheads in multi-point networking, and can accurately reflect the current most-true link condition. The present invention furthermore discloses a device for optimizing an OLSR protocol through multiple parameters.

The invention relates to the field of data processing, in particular to an environmental data lattice point processing method based on a graph convolutional network. The method comprises the following steps: acquiring air quality monitoring data and meteorological monitoring data in a target area; missing processing is carried out on all the monitoring data, and the monitoring data of the sites are mapped into a lattice point matrix divided by the target area; generating a dynamic wind field graph by using the wind direction data and the wind speed data, and calculating a wind field adjacent matrix by using a Dijkstra algorithm; constructing a mask matrix at each moment according to the air mass concentration data, and constructing a feature vector set Z at each moment according to the wind field adjacent matrix, the mask matrix and the meteorological monitoring data; generating a target matrix Y at each moment according to the mask matrix and the air mass concentration data; and inputting the eigenvector set Z matrix into the trained graph convolutional neural network model to obtain an estimation matrix P of the target matrix. According to the invention, the accuracy of environmental data gridding can be improved.

The invention provides an aviation accessibility measuring and calculating method and system and a storage medium. The aviation accessibility measuring and calculating method comprises the steps of arrival time calculation, waypoint coverage calculation, flight density calculation and flight balance degree calculation. According to the method, the requirement of accessibility measurement and calculation is met mainly through four indexes of accessibility time, waypoint coverage, flight density and flight balance degree, and a path algorithm suitable for aviation path calculation and accessibility measurement and calculation is developed on the basis of dynamic planning, a greedy algorithm and a forward and reverse Dijkstra algorithm. The method effectively makes up for the vacancy that a traditional route calculation mode cannot calculate a flight route of one-time transfer or two-time transfer and the defect that manual calculation consumes too long time, and a flight season gt can be calculated within one and a half hours through a server; all waypoints of the whole country to all waypoints gt of the whole country; the optimal arrival path and arrival time of the normal commuting time point in one week ensure the accuracy and effectiveness of the result, and are far higher than the manual calculation efficiency.

The invention discloses a storage robot indoor mapping navigation system based on a laser radar, and the system comprises a storage robot which is used for automatically scanning the surrounding environment through the laser radar, obtaining a laser data point set, and building a two-dimensional grid map through employing an approximation synchronous positioning and mapping algorithm based on the laser data point set, performing pose estimation on the laser data point set by using a least square method or singular value decomposition, constructing a two-dimensional grid map according to a pose estimation result, updating the two-dimensional grid map to a warehouse system in real time, determining an optimal path by using a Dijkstra algorithm based on the two-dimensional grid map, and performing positioning navigation according to the optimal path; a warehouse system which is used for receiving and storing the two-dimensional grid map and sending instruction information to the storage robot; and a mobile control terminal which is used for sending instruction information to the storage robot; the indoor mapping navigation system disclosed by the invention has relatively high mapping and directional navigation precision and relatively low data processing amount.

The invention discloses a rapid transmission method of model data in distributed simulation of power equipment. The method comprises the steps of constructing a network topological graph of each site in a simulation system of the distributed power equipment, obtaining mean data transmission time between the sites, generating a shortest path tree taking a target site as a root node by using a Dijkstra's algorithm, generating a structure tree of a simulation model, analyzing a required submodule in a target included in each site, forming a submodule transmission candidate list, carrying out submodule transmission path planning from small to large from a leaf node according to the transmission time based on the list and the structure tree of the model to achieve rapid distributed transmission of the simulation model of the power equipment. The method greatly improves model transmission efficiency in the distributed simulation system, shortens the transmission time of a model network, and therefore ensures a simulation effect and continuity.

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.