460 results about "Graph theoretic" patented technology

The present invention relates to a hierarchical system and method for task assignment (TA), coordination and communication of multiple Unmanned Aerial Vehicles (UAV's) engaging multiple attack targets and conceives an ad-hoc routing algorithm for synchronization of target lists utilizing a distributed computing topology. Assuming limited communication bandwidth and range, coordination of UAV motion is achieved by implementing a simple behavioral flocking algorithm utilizing a tree topology for target list routing. The TA algorithm is based on a graph-theoretic approach, in which a node locates all the detectable targets, identifies them and computes its distance to each target. The node then produces an attack plan that minimizes the sum of distances of the UAV's in the subtree of a given node to the targets.

This invention relates generally to medical imaging and, in particular, to a method and system for reconstructing a model path through a branched tubular organ. Novel methodologies and systems segment and define accurate endoluminal surfaces in airway trees, including small peripheral bronchi. An automatic algorithm is described that searches the entire lung volume for airway branches and poses airway-tree segmentation as a global graph-theoretic optimization problem. A suite of interactive segmentation tools for cleaning and extending critical areas of the automatically segmented result is disclosed. A model path is reconstructed through the airway tree.

A system and methods for the efficient segmentation of globally optimal surfaces representing object boundaries in volumetric datasets is provided. An optical surface detection system and methods are provided that are capable of simultaneously detecting multiple interacting surfaces in which the optimality is controlled by the cost functions designed for individual surfaces and by several geometric constraints defining the surface smoothness and interrelations. The present invention includes surface segmentation using a layered graph-theoretic approach that optimally segments multiple interacting surfaces of a single object using a pre-segmentation step, after which the segmentation of all desired surfaces of the object are performed simultaneously in a single optimization process.

A method and system are disclosed for changing the structure of one or more policies and/or the order of application of one or more policies to resolve conflicts among a set of policies using graph-theoretic techniques. Policies are used to govern the states of managed entities (e.g., resources and services). The set of states of the set of managed entities are represented as nodes of a graph. The output of the set of applicable policies governing all or part of the nodes is then used to control the transition between some or all nodes in the graph.

A novel method is presented for detecting coronary arteries as well as other peripheral vessels of the heart. After finding the location of the myocardium through a segmentation method, such as a graph theoretic segmentation method, the method models the heart with a biaxial ellipsoid. For each point of the ellipsoid, a collection of intensities are computed that are normal to the surface. This collection is then filtered to detect the cardiovascular structures. Ultimately, vessel centerline points are detected using a vessel tracking method, and linked together to form a complete coronary artery tree.

The invention belongs to the field of unmanned ship global path planning and particularly relates to an unmanned ship global path multi-target planning method based on the improved ant colony algorithm. The method comprises steps of establishing a marine environment map model by utilizing a Maklink graph theory; improving a path heuristic information strategy to obtain a path average value; designing an ant pheromone volatilization adaptive adjustment strategy; designing a strategy combining local pheromone updating and global pheromone updating; improving the state transition probability of anext node searched by an ant colony through a heading angle deviation factor of an unmanned ship; and designing an evaluation function by integrating the requirements of the shortest global path length, the least optimization iteration times of the improved ant colony algorithm, the lowest path smoothing coefficient and the like. The method is advantaged in that multiple targets such as a globalpath distance of marine navigation of an unmanned surface vehicle, the iteration frequency of optimizing the global path by improving the ant colony algorithm and the smoothness coefficient of the planned global path are comprehensively considered, the optimal global path of marine navigation of the unmanned surface vehicle is finally planned, and the method has relatively high safety.

A functional coverage based test generation technique for pipelined architectures is presented. A general graph-theoretic model is developed that can capture the structure and behavior (instruction-set) of a wide variety of pipelined processors. A functional fault model is developed and used to define the functional coverage for pipelined architectures. Test generation procedures are developed that accept the graph model of the architecture as input and generate test programs to detect all the faults in the functional fault model. A graph model of the pipelined processor is automatically generated from the specification using functional abstraction. Functional test programs are generated based on the coverage of the pipeline behavior. Module level property checking is used to reduce test generation time.

The invention provides an energy efficient resource distribution algorithm based on interference coordination in an ultra-dense wireless network. A clustering-based ultra-dense wireless network is analyzed and given; inter-cluster and in-cluster interference coordination strategies are provided; inter-cluster interference coordination is carried out by adopting a graph colouring theory; and in-cluster interference coordination is carried out in a partial information interaction manner. The energy efficient resource distribution algorithm based on interference coordination in the ultra-dense wireless network is provided. Joint optimization of sub-channels and power of the ultra-dense wireless network is carried out through the algorithm. Firstly, the sub-channels are distributed by utilization of a user quality experience function and maximum and minimum algorithms; and secondly, optimization distribution of the power is carried out by optimizing an improved particle swarm algorithm, wherein to prevent particle swarm optimization from getting into local solution defect, a particle swarm optimization algorithm is improved by introducing damped vibration and fitness variation.

The present invention provides a shared bicycle scheduling method and a scheduling system, the scheduling method and the scheduling system establish a VRPSPD model for the shared bicycle scheduling problem, and obtain the optimal scheduling scheme by solving the model through a hybrid variable neighborhood discrete particle swarm algorithm; due to the establishment of the present invention The VRPSPD model integrates graph theory and mixed integer programming theory, and at the same time combines VRPSPD model and m-TSP model to establish, so it is more comprehensive; and the hybrid variable neighborhood discrete particle swarm algorithm combined with discrete particle swarm fast convergence and high precision The ability of the algorithm and the local search ability of the variable neighborhood search algorithm can prevent the discrete particle swarm from falling into the local optimum during the optimization process, so that the real optimal scheduling scheme can be obtained to solve the scheduling problem of shared bicycles and improve the operation of shared bicycles. Efficiency and management scheduling level, effectively improve vehicle utilization.

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 Stackelberg game-based resource allocation method. According to the method, the interference of a cellular and femtocell-coexisting and spectrum-shared two-layer network is analyzed and managed; graph theory knowledge and the game theory are adopted to allocate resources used by users in femtocells and a macro base station, so that the quality of services for the users can be ensured. The method includes the following steps that: a graph theory-based clustering algorithm clusters the femtocells and sequentially allocates channels for macro users, and then matches the macro users with femtocell clusters so as to realize channel sharing; and a femtocell transmission power and macro user access selection-combined Stackelberg game is established, and the expression of the transmission power of the femtocells when Nash equilibrium is achieved is derived, and appropriate access strategies are selected for the macro users according to the transmission power of the femtocells, and iteration is repeated until Stackelberg game equilibrium is achieved, and network resource allocation is updated according to strategies which are selected when the equilibrium is achieved.

The invention discloses a method and a system for predicting power of a microgrid group. The method comprises steps: a microgrid graph theory model is built according to a communication relation between sub microgrids in the microgrid group; according to an intelligent agent node consistency theory and in combination with a micro Calman filter prediction algorithm, a power prediction algorithm for distributed prediction for needed power by a total grid of the microgrid group is determined; on the basis of the already-built communication relation graph theory topology, each sub microgrid in the microgrid group integrates grid needed power information of a local sub microgrid system and an adjacent sub microgrid system and uses a prediction algorithm to distributively perform short-term prediction on the needed power by the total grid of the microgrid group in the local sub microgrid system. Short-term prediction is carried out on the overall grid needed power of the microgrid group formed by multiple microgrids, and strong guarantee is provided for aspects of stable operation and power dispatching for the microgrid group power sharing system.

The invention relates to the technology of topology analysis in the field of an electric power system, and specifically relates to a method for rapid topology analysis and the establishment of a topological island based on a graph theory. The method includes three steps: modeling, generating topology points, and generating the topological island. According to the method, topology analysis of the electric power system can be conducted via a graph theory recognition analysis method; advantages and disadvantages of breadth and depth first search algorithms can be comprehensively considered, and search advantages of depth first for a ring network are fully used; rapid topology analysis of the electric power network and the establishment of the topological island are realized, and the accuracy and rapidity of the topology analysis result of the electric power network are greatly improved.

Automated, standardized and accurate extraction of relationships within text. Automatic extraction of such relationships/information allows the information to be stored in structured form so that it can be easily and accurately retrieved when needed. Such information can be used to build online search engines for highly specific and accurate information retrieval. The current invention discloses a novel approach to extract such information from raw text based on natural language processing (NLP) and graph theoretic algorithm. The novel method can be applied, for example, to extract protein-protein relationships in biomedical literature. The method can be easily extended to extract other biological relationships between biological terms such as proteins, genes, pathways, diseases and drugs. The method can also be applied to other information domains to extract other relationships.

The invention relates to an automatic order arranging and scheduling method in warehouse management. Firstly, goods are stored according to preset rules and order information is managed. Secondly, theroute planning management is carried out according to the storage situation of goods and the order information. In the path planning management, by introducing the TSP problem in graph theory, multi-AGV path planning is carried out for orders with large demand, and a collision-free and coordinated path is planned for each AGV by using the time window and one-way directed graph method, so as to eliminate collision and deadlock in multi-AGV path planning. For the orders with small demand, the single AGV path planning is carried out, and the TSP problem in graph theory is used to solve the problem, so as to achieve the shortest total distance. The invention can save time and improve the picking efficiency.

The invention relates to a target retrieval system applied to a moving platform and belongs to the image processing field. The target retrieval system applied to the moving platform aims to provide a grading significance information method applied to the moving platform, can not only improve discrimination capability for characteristics in a significance area, but also can reserve retrieval content in a non-significance area. The method comprises steps that, pre-processing on images in an image database in a server is carried out, grading significance areas are extracted according to a significance model based on the graph theory and a two-dimensional maximum entropy rule, a global histogram with significance labels is generated by utilizing a word bag model, SIFT characteristics of the images are calculated and queried, the global histogram is generated by utilizing the word bag model, first 1000 retrieval image sequence numbers having shortest distances are recorded, and first 10 images in the final retrieval result are returned to a mobile terminal and are displayed. The target retrieval system is a relatively rapid and effective mobile visual searching system and can detect error coupling with more robustness.

According to the structure characteristic of an alternating current region power supply system of a ring-shaped bus, through improvement on several short circuit computing methods which are widely used in the prior art at home and abroad, the original short circuit current computing method for a tree-shaped power grid is deformed into a short-circuit current computing method suitable for a ring-shaped ship power grid. The method comprises the following steps of: firstly, computing the short-circuit current of a simple grid by a star-network transformation and local equal effect method; and secondly, providing a method in which a line impedance matrix is obtained by a graph theoretic approach and then the short circuit current is calculated. According to the method, the short-circuit current computing method for a ship ring-shaped region power distribution system can be explored, the thermal stability and power stability checkout when types of the equipment are selected can be realized, and the basis can be provided for fault protection when the equipment runs.

The invention discloses a self-repairing system and a self-repairing method for an optical fiber distributed sensor network. The system consists of a plurality of optical fiber grating sensors, a self-repairing controller, an optical fiber grating demodulator and a PC. The method is to arrange the self-repairing controller inside an optical fiber network, judge local failure of the optical fiber network after damage by a granularity calculation method, and perform recombination repair on a failed local network by a graph theory method so as to guarantee that the optical fiber network can be operated normally when partial optical fibers fail locally. When an optical fiber sensing system is damaged and partially fails, the self-repairing system and the self-repairing method can automatically recombine the network and repair the functions of the network, make an intelligent material structure capable of realizing self-repairing, and improve the reliability of the optical fiber intelligent structure in engineering application.

The invention discloses an unmanned vehicle multi-lane navigation formation method based on a graph theory and a potential field method. The method comprises the following steps of 1), transmitting the predefined formation structure information to the vehicles according to the formation control of an unmanned vehicle fleet, wherein the formation structure information comprises the number of vehicles with a team forming relation, the positions of the vehicles, and the expected distances between the vehicles; 2) planning the speed and displacement required for keeping the formation by using a graph theory method and according to the predefined unmanned vehicle formation and the distance between the unmanned vehicles; 3) obtaining the unmanned vehicle formation trajectory planning according to the unmanned vehicle fleet formation planning, and performing unmanned vehicle obstacle avoidance trajectory planning on the formation trajectory planning; and 4) weighting the unmanned vehicle formation trajectory planning and the planning result of the unmanned vehicle formation trajectory planning to obtain the final planning result of the vehicle and generate the final trajectory. The methodcan adapt to the traffic scene change and automatically change the formation so as to improve the traffic safety and efficiency.

The invention discloses a mathematical talent teenager brain network analysis method based on a weighted phase lag index, and the method comprises the steps: constructing a phase synchronization network based on a task state EEG signal through employing an algorithm based on the weighted phase lag index, and converting the phase synchronization network into a functional connectivity network; and measuring the connection network by utilizing graph theory indexes, and describing connection network characteristics of the mathematical talent teenagers, including active brain regions and the graphtheory indexes. Compared with the prior art, the method provided by the invention has the advantages that the connection network characteristics of the mathematical exceptional teenagers are describedbased on the task state EEG signals, and the phase synchronization network is constructed by adopting the weighted phase lag index and is converted into the functional connection network, which reduces the probability of detecting false positives when the phase difference between volumetrically conducted noise sources is zero, and increases the sensitivity of detecting phase synchronization.

The invention discloses a comprehensive resistance weight and graph theory-based river network connectivity assessment method. The method includes the following steps that: a river network is generalized into a directed river network graph model which adopts river sections as edges and adopts the sources, convergences and intersections of rivers, as well as gate dams as vertexes; the resistance items, namely, hydrology, hydrodynamic force, water quality and human activities of any of river sections are calculated, the comprehensive resistance weight (CRW) of the river section is calculated; and the CRW of each river section in the river network is calculated as the previous step, and the CRWs of the river sections are adopted as the weights of the edges, so that a river network weighted adjacency matrix can be established, and a minimum comprehensive resistance matrix can be also obtained, and therefore, the minimum comprehensive resistance of the river network can be obtained, and the reciprocal of the minimum comprehensive resistance of the river network is solved, so that the comprehensive connectivity index (CCI) of the river network can be obtained. According to a method for optimizing a river network gate dam system by using the above method, any one gate dam in the river network is removed sequentially, and comprehensive connectivity indexes (CCI) are calculated again, so that the obtained comprehensive connectivity indexes (CCI) are arranged according to a large-to-small order, and the arrangement order is a priority removing order, and the river network gate dam system is optimized according to the priority removing order.