68 results about "Path (graph theory)" patented technology

The invention discloses an entity attribute information extraction method and device based on syntactic dependency. The method comprises the steps that firstly, a to-be-extracted text is preprocessedto obtain a to-be-extracted text entity; then, according to the syntactic dependency and the part-of-speech relation of the to-be-extracted text, an undirected weighted graph between words is established, and candidate attribute information of the to-be-extracted text entity is obtained according to the part-of-speech relation; the shortest path between the to-be-extracted text entity and the words of the candidate attribute information is searched for, and the words passing through the shortest path form an association information word set; finally, the semantic similarity between each attribute in the attribute set and the association information word set is calculated, an entity attribute is obtained, and the entity, the entity attribute and the attribute information are integrated to serve as a final extraction result. The natural language processing technology and the graph theory model are combined, the ambiguity of text information is solved, and the text extraction accuracy isimproved; the semantic similarity of the keywords is utilized, the attributes of the abstract information are automatically summarized, and the extraction efficiency is improved.

The invention discloses a terminal sector dividing method based on the graph theory and the spectral clustering algorithm. The method is carried out with the help of a computer system which comprises a sector dividing subsystem. The terminal sector dividing method comprises the first step of putting forward a calculating model of a peak connection degree according to the basic airline network structure and air traffic flow in controlled airspace, the second step of effectively dividing peaks of an airspace image based on the spectral clustering algorithm to solve the problem of a division error in short-distance parallel air routes and to achieve construction and division of a sector convex hull, the third step of putting forward a boundary optimized path selection algorithm based on sectors of an MAKLINK image, and the last step of carrying out optimizing to eliminate a sawtooth shape of the boundaries of the sectors to some degree to enable the sector boundaries to be more conform to actual operations so that the final dividing of the sectors can be finished. By means of air traffic flow, reverse deduction is carried out conveniently while the sectors are divided. By means of the terminal sector dividing method based on the graph theory and the spectral clustering algorithm, flows of the sectors are balanced, coordination is small, minimum distance constraint is met, the difficulty of commanding of a controller is reduced, and the security of operation in the terminal area is guaranteed.

The invention discloses a plane switching operation hook planning compilation method for a middle railway station. A modularization structure is adopted. The modularization structure comprises a hook planning graph automatic compilation module, and is characterized in that the graph automatic compilation module is a graph theory model for designing an optimal train set arrangement sequence, wherein the graph theory model is about converting solving of the compiled optimal arrangement sequence into solving of a minimum Hamilton path of a digraph, namely, the minimum Hamilton path is a path passing each vertex of a graph or the diagraph only once.

The invention provides a chemical process fault diagnosis method for Bayesian networkbased on a mechanism correlation analysis and the method comprises the steps: analyzing the mechanism correlationsbetween unit variables of a chemical process, and obtaining a relation matrix; calculating the conditional probability of the Bayesian network by using confidence interval estimation of historical data, and establishing the Bayesian network in combination with the relationship matrix; adopting a principal component analysis method to monitor the process; when a fault is detected, conversing data state, and calculating Bayesian contribution of a variable; adding evidences of fault nodes into the Bayesian network, finding out propagation paths and root nodes of faults, obtaining real reasons ofthe faults according to the propagation paths and the root nodes of the faults, and finding out root reasons of the faults from the Bayesian network in combination with mechanism-related process knowledge. The graph theory modeling of the technological process model is realized, the priori knowledge of the mechanism model and the quantitative calculation of the historical data are combined, and the method has the characteristics of simplifying the calculation amount and improving the calculation precision.

The invention relates to an intelligent path planning method for a fire-fighting robot. The method comprises the steps: performing preprocessing according to space environment information of a fire scene where the fire-fighting robot is located; constructing a concave-convex polygonal obstacle fire scene space environment model according to an extended MAKLINK graph theory; planning an initial path by adopting a Dijkstra algorithm according to the stationing point and the fire extinguishing point of the fire-fighting robot; and on the basis of the fire scene space environment model and the initial path, introducing a self-adaptive dynamic adjustment strategy of pheromones and heuristic values, performing iterative search on path nodes in an ant transfer process by utilizing an improved antcolony algorithm, and finally obtaining an optimal planned path. According to the method, the advantages of an extended MAKLINK graph theory and an improved ant colony algorithm are combined, optimalpath planning can be achieved in a complex fire scene space environment containing concave-convex polygonal obstacles, the algorithm convergence speed is high, and the path planning capacity is high;in addition, the feasibility and effectiveness of the provided technical scheme are verified through a simulation test.

The invention discloses a graph theory-based travel accessibility calculation and display method under a networked operation condition. The method comprises the steps of S1, establishing a line network static model based on a graph theory and storing station basic information; s2, receiving OD information to perform dynamic travel accessibility calculation; s3, providing travel accessibility queryand display to the outside through a cross-terminal platform; according to the scheme, the urban rail transit station simplified model is established through the graph theory; a Dijkstra algorithm isused to find the shortest path between any OD; according to the method, the effective path set existing in the line network is searched according to the depth-first search algorithm, meanwhile, subway travel calculation associated with the train running chart is achieved, development of travel calculation query programs of a computer terminal and an enterprise WeChat terminal is completed, passengers can estimate travel conveniently, and the passing efficiency is improved.

The invention discloses a medium-voltage power distribution network topology simplification and abstraction method based on a graph model. The method comprises the steps: modeling the medium-voltage distribution network topology by using the graph model; simplifying a medium-voltage power distribution network, and realizing the progressive abstract simplification of an original path, a key path, acore path and a core extremely-simple path by utilizing technologies such as homomorphic transformation and heavy edge elimination in a graph theory, and providing applicable topology levels for microscopic, mesoscopic and macroscopic application scenes such as feeder line maintenance inspection, distribution network maintenance and regulation and control operation and power grid planning. Through layer-by-layer abstraction, the complexity of the distribution network topology is effectively reduced while the characteristics of the distribution network are maintained, so rapid analysis and visualization of various microscopic, mesoscopic and macroscopic business scenes such as feeder line patrol inspection, distribution network transfer analysis and power grid planning are realized.

The invention relates to a method for solving the optimal path of a wireless sensor network by using differential evolution. According to the method, an undirected graph is utilized to describe wireless sensor network path problems and research nodes and information transmission in the wireless sensor network according to graph theory knowledge; the undirected graph can be expressed by an equation that G=(V,E), wherein V indicates the set of all nodes of the network, E is the set of all communication lines, V=Vhead, V1,... , Vk,... , Vn, and E=E1,... , Ek,... En; Vhead is assumed to be the target node in the cluster, namely, a cluster head node; a k-th node is adopted as a source node, and a path optimization model is established; a differential evolution algorithm is adopted as a search tool to find minimum energy consumption required by information transmission from the source node to the target node; and a path with minimum energy consumption required by information transmission from the source node to the target node is found. With the method adopted, an optimal transmission path with minimum energy consumption can be calculated quickly and accurately.

The invention provides a crowd evacuation bottleneck congestion condition analysis method and system, and the method comprises the steps: constructing an evacuation network according to the layout condition of a building, and enabling the evacuation network to comprise nodes and edges for connecting the nodes; determining the shortest path from each node in the evacuation network to an exit; and in the crowd evacuation process, determining people flow data corresponding to the bottleneck position on the shortest path. According to the method, people flow data of different bottleneck positionsof any building can be obtained, so that guidance is provided for safe evacuation; a user can understand the topological structure of the building from the perspective of the graph theory, so that thearchitecture suggestion of the evacuation network is given in the early stage of building design, and the internal design of the building is more reasonable.

The invention provides a combined cooling heating and power system construction method and system based on a graph theory and an equivalent electrical method. The method comprises steps of constructing an energy supply and energy consumption model of the energy flow network according to a graph theory thought, selecting the maximum equivalent electric weight as a target function, analyzing and comparing each selectable path in the graph theory model to obtain an optimal energy supply path, and determining an energy supply structure of the combined cooling heating and power supply system. According to the node type and graphical design method provided by the invention, the aspects of multi-energy types, multi-equipment structures, multi-energy supply path coupling and the like are considered, and an idea is provided for the structural design of the multi-source multi-sink multi-path coupling CCHP system.

The invention discloses a piping shaft optimization algorithm, and relates to the field of architectural design and electromechanical design. The method is characterized by comprising the following steps of: extracting room information and possible positions of the piping shafts from a building information model, and automatically solving a shortest path pipeline from each possible position of each piping shaft to each tail end by adopting a Pramer algorithm on the basis of a graph theory and a minimum spanning tree thought in combination with an arrangement position of tail end equipment in electromechanical design; and calculating the resistance of each solved shortest path pipeline and the unbalance degree of the system, and selecting the piping shaft with the minimum pipeline resistance within 15% of the unbalance degree of the system as the optimal piping shaft position. The comprehensive optimal design of simple system pipeline arrangement, good system balance, resistance reduction, energy-saving operation and the like is achieved.

The invention provides a substrate design method and device of a power module and terminal equipment, and belongs to the technical field of power modules. The method comprises the following steps: acquiring input parameters of a substrate for designing a power module; according to the information of the circuit topology and a pre-stored structure diagram of each basic layout unit, determining the type and the number of the basic layout units on the circuit topology; and connecting the communication paths of the graph elements of the basic layout units on the circuit topology by using a path-finding model to obtain a connection graph of the substrate of the power module. In the application, the graph theory model of the basic layout unit is defined, the relative position and the connection relation of the basic layout unit are described, the optimal communication path in each commutation network is determined on the circuit topology through the integer programming model, and the node and the interconnection edge of the line unit corresponding to each optimal communication path are established. In the process, the input of a manual layout template is not needed, and the substrate layout autonomous design of the power module is realized.

The invention provides a multi-beam channel modeling method based on a propagation graph theory, which corrects propagation path gains related to a transmitting and receiving end by solving gains of a transmitting and receiving end antenna array at various angles, and divides scatterers into a static discrete scattering point set and a dynamic discrete scattering point set in consideration of mobility of obstacles, and different scattering times are considered for two different scattering point sets to construct a multi-beam channel model based on a propagation graph theory. According to the method, the defect that beam forming is not considered in an existing propagation graph channel modeling theory is overcome, and the accuracy of channel modeling is improved.

The invention discloses a path optimization method for concrete 3D printing. The path optimization method comprises following steps: step 1, slicing a printed piece model; step 2, converting the sliced model into a geometric model; step 3, initializing position information of geometric points in the geometric model, and dividing the geometric model into a plurality of areas which can be printed at a time according to a graph theory principle; and step 4, finding out a shortest printing path by adopting an ant colony algorithm. According to the method, the scanning sequence and the scanning starting point of each contour are reasonably planned, inflection points of a contour path in the 3D printing and scanning process are reduced, the idle stroke of the contour path is shortened, and the forming speed and quality are improved.