307 results about "Breadth-first search" patented technology

The invention discloses a method and a device for evaluating system security based on correlation analysis. The method comprises the following steps of using an attack graph model to perform the correlation analysis on the network security condition, adopting an attack graph generation algorithm based on breadth-first search, introducing a PageRank calculation model to quantize the weights of state nodes of the attack graph, utilizing the difference of the weights to judge the critical attack nodes of the attack graph, utilizing a depth-first search algorithm to find the critical attack path in the attack graph, finally providing the network security amount based on the attack graph, quantizing the risk value of the critical attack path of the attack graph, and quantizing the security of the whole network.

The invention provides a power distribution network topology layout method. The method comprises the step of obtaining geographical position data of nodes of an electric power system, the topology information of connection of the nodes and line hardware parameter information among the nodes and selecting the node closest to a power transmission network as an original female node, the step of obtaining the on-off state, power parameters, interphase faults and grounding faults of spot switches of the nodes of the power transmission network and the voltage and current parameter information of the spot switches when the faults happen, the step of extracting the topology relation among the nodes through a first-level breadth-first search method, the step of determining the types of devices of the nodes through a second-level breadth-first search method, the step of traversing, searching for and determining the types of the devices of the nodes through the breadth-first search methods to carry out layout numbering, and the step of determining the distance between every two adjacent nodes on a topology graph and the transverse distance and the longitudinal distance of the nodes relative to the female node and carrying out the topology layout and display. The repeated nodes in the current power transmission network topology graph are removed through a longitudinal symmetrical layout method and a longitudinal draw type wiring method, and the power transmission network topology layout is carried out.

An automated approach to generating test cases for performance testing may be used for test case planning, early in the software development process, when a UML use case model and its activity diagram refinement are specified. The planned performance tests are executed later in the software development process, after the system is developed. The use case model is annotated with operation arrival rates and departure rates. Deterministic state testing (DST) generation and execution are applied for performance test generation and execution. In addition, a technique is described to generate the most likely test scenarios, labeling each arch in the activity diagram with transition probabilities and applying a breadth first search algorithm to select the most likely paths to be tested for each state generated by the DST algorithm.

The invention belongs to the technical field of laser radars, and discloses a depth map-based three-dimensional laser radar point cloud target segmentation method, which comprises the following stepsof: converting three-dimensional point cloud data acquired by a three-dimensional laser radar into a two-dimensional depth map; calculating an angle value formed by two adjacent points in each columnin the depth map, and traversing to obtain an angle matrix corresponding to the depth map; traversing the depth map through a breadth-first search algorithm, if the angle difference between two pointson adjacent positions of the depth map is smaller than a specified threshold value, marking the depth map as the same type, thereby finding out the part, belonging to the ground, in the depth map, and removing ground point cloud data according to the mapping relation between the point cloud and the depth map; and carrying out target segmentation on the non-ground point cloud based on an improvedDBSCAN algorithm, and judging whether the point cloud is a core point or not according to an adaptive parameter eps while considering a spatial Euclidean distance and an angle distance. According to the method, the segmentation efficiency on the depth map is improved, the real-time requirement is met, and the problems of under-segmentation and over-segmentation are effectively solved.

A hybrid sphere decoding method is disclosed. Received data is processed to obtain preliminary parameters. M_bf layers are determined to use breadth-first search and M_df layers to use depth-first search. A search process is implemented based on the preliminary parameters, in which M_bf layers are searched using breadth-first search and M_df layers are searched using depth-first search.

The invention discloses an arteriovenous retinal blood vessel classification method based on an eye fundus image. The method includes the steps that first, a global blood vessel set and optic disk positioning information of the fundus image are acquired, the global blood vessel set is a set of all blood vessels in the fundus image, and the optic disk positioning information comprises the optic disk center of the fundus image; second, main blood vessels are determined according to the global blood vessel set and the optic disk positioning information and classified so that main blood vessel classification information can be obtained; third, the main blood vessel classification information is used for classifying the blood vessels in the global blood vessel set through a breadth first-search algorithm based on SAT so that global classification information can be obtained. According to the method, the classification information of the main blood vessels around an optic disk is first obtained, external expansion diffusion is performed from the main blood vessels through the breadth first-search algorithm based on SAT so that all the blood vessels can be obtained, a complete automatic blood vessel classification method is achieved, manual intervention is not needed, and classification precision is high.

The invention provides an unmanned vehicle track real-time planning method based on road structure weight fusion, which is suitable for intelligent track planning of an unmanned vehicle in an autonomous driving process. The technical scheme adopted by the invention comprises the following steps: 1. simplifying the calculation of a vehicle motion equation by a table lookup mode; 2. adopting a structured and unstructured environment weighting method based on breadth-first search; 3. conducting a dynamic target area decision; 4. adopting an improved A* path search algorithm fused with vehicle dynamics; and 5. conducting an incremental track planning of a dynamic scene. The unmanned vehicle track planning problems under various environments are unified by using a structured and unstructured environment weighting method; the continuity and the stability of the track are realized by utilizing the incremental track planning of a dynamic scene, and the running stability of the unmanned vehicleat low, medium and high speeds is ensured; and a vehicle motion equation and a collision detection process are simplified and approximated, the efficiency of a track planning algorithm is effectivelyenhanced by avoiding floating point operation, the track planning algorithm is enabled to achieve nearing real time, and the correctness of track planning is guaranteed.

The invention provides a virtual network mapping method of an elastic optical network facing an SDN, and mainly solves the problem in the elastic optical network facing the SDN that a network virtualization mode is utilized to realize flexible distribution and scheduling of network resources. The method specifically comprises the steps of: 1, obtaining underlying networking information; 2, receiving virtual network request information; 3, obtaining an alternative programmable physical node set; 4, mapping virtual network nodes; 5, judging whether all virtual node of the current virtual network have been mapped into a physical network; and 6, carrying out virtual network link mapping. According to the invention, the virtual node mapping method based on distance and comprehensive resource sensing, a breadth-first search method and an improved shortest path algorithm based on available space closest matching are utilized, the blocking probability of virtual network mapping is lowered, the bandwidth resource consumption of the physical network is reduced, and the future virtual network business bearing capability of the network is improved.

A method and apparatus for encoding and/or decoding depth image-based representation (DIBR) data are provided. The encoding method includes: converting 3-dimensional (3D) volume data into adjustable octree data with predetermined labels given to nodes; by referring to the labels, encoding nodes of the adjustable octree from the root node to leaf nodes by a modified breadth-first search (BFS) method allocating priorities among children nodes; and generating a bitstream with predetermined header information and encoded node data. The decoding method includes: extracting header information containing at least resolution information of an object, from a bitstream and decoding the header information; calculating the number of nodes by using the resolution information of the header, and by a modified BFS method allocating priorities among children nodes, decoding each node of a tree from the root node to leaf nodes; and restoring an adjustable tree by using decoded nodes. According to the method and apparatus, a huge amount of 3D volume data can be encoded with a high efficiency, and volume data with an arbitrary resolution as well as volume data with a fixed resolution can be encoded with a high efficiency. Accordingly, with a small amount of data, 3D volume data with a high picture quality can be restored. In addition, since a progressive bitstream is generated, 3D volume data can be shown progressively when decoding is performed.

The invention provides a content route managing method of a fusion type content distribution network, belonging to the technical field of internet. The invention aims to provide a two-layered content node deployment mechanism aiming at ISP-CDN (Internet Service Provider-Content Distribution Network) and design an indexing and synchronization mechanism to improve a content route policy under a CDN environment; a flow settlement cost and data transmission quality are considered. The network data is singly processed, namely the flow cost consumed by primary transmission is only related with a passed route hop count and the size of the data is not considered; an inverse ratio relation is formed between the node quantity selected from a core route node set F and the repeated flow; a synchronous cost is in direct proportion to the node quantity; a synchronous initial source is an inter-domain router node; with regard to an inter-domain route node t, a breadth first search algorithm is used for generating k content nodes covered by a minimum spanning tree TR which takes the t as a root; the k notes are found and an RC+SC minimum is realized by adopting an algorithm based on a greedy strategy.

The invention discloses a topology automatic-discovery and breadth-first loop tree layout method based on a simple network management protocol (SNMP) and an Internet control message protocol (ICMP), and belongs to the field of network management and control. The method comprises the following steps of: performing SNMP polling to automatically discover connection relations among all the network equipment of a managed network and connection relations between the network equipment and sub-networks, and storing the connection relations into a database; discovering active hosts in all the sub-networks by using a ping tool in the ICMP, and storing the connection information of the active hosts into the database; and obtaining the loop topology of all the network equipment and the sub-networks in the managed network on the basis of a breadth-first search algorithm, wherein the active hosts in the sub-networks form Y connection with routers of the sub-networks. By the method, the connection relations among all the network equipment, the connection relations between the network equipment and the sub-networks and the active hosts in the sub-networks in the managed network are automatically discovered, and the topology of the managed network is hierarchically and visually displayed to a network manager.

Tracing a short as a shortest path of explicit VLSI design component instances between two VLSI design component instances with different net names in a hierarchical design is a non-hierarchical problem. The method described in this document computes a shortest path of VLSI design leaf component instances containing at least one of the leaf design components causing the sort. To avoid exceeding available storage, the non-hierarchical instance information maintained during the process is pruned optimally. To achieve feasible performance, two methods to find "good" starting points are provided, based on geometrical distribution or based on connectivity information from the net build (if available).

The invention provides a virtual network mapping method and system based on a cut set. A breadth-first search tree is firstly built based on the network topology of a virtual network, the cut set of the virtual network is calculated, virtual nodes in the virtual network are mapped based on the breadth-first search tree, and after each virtual node is mapped, virtual links connected with the virtual nodes are mapped; when the virtual links are mapped, whether a cut set including the virtual links exits or not is firstly judged, the virtual links are mapped to the physical link with the minimum load if the cut set does not exist, whether other virtual links in the cut set except for the virtual links are mapped to physical links connected with the same physical node or not is judged if the cut set exists, and the virtual links are mapped to the physical link with the minimum load except for the physical links directly connected with the same physical node if the other virtual links in the cut set except for the virtual links are mapped to the physical links directly connected with the same physical node. The light reliable need of the virtual network is met, and the long-term even operating benefit of a physical network is improved.

According to one embodiment, an information processing apparatus comprises a storage storing program modules and parallel execution control description describing relationships of the program modules, a conversion module extracting a part relating to the program module from the parallel execution control description, and creating graph data structure creation information including preceding and succeeding information of the program module, an adding module extracting graph data structure creation information to which the input data is given, creating a node, and adding the created node to a formerly created graph data structure, and an execution module subjecting the graph data structure to at least one of depth-first search and breadth-first search with a restricted breadth, selecting one node from nodes stored in the node memory, and executing a program module corresponding to the selected node.

The embodiment of the invention provides a transmission line relay protection control service channel route configuration method and device. The specific implementation way of the method comprises the following steps: according to information of an initial node and a terminal node in a received route configuration request, and network topology information, determining a plurality of routes between the initial node and the terminal node by adopting breadth-first search, and obtaining a first route set; determining a risk value corresponding to each route according to a node included in each route in the first route set and a risk value of each conserved node; recognizing routes that the corresponding risk values of the routes are smaller than a preset risk threshold and the born service quantity and the residual bandwidth meet a preset condition from the first route set, and acquiring a second route set; and recognizing routes of a preset first quantity threshold with smaller time delay values in the second route set, and taking the recognized routes as configured routes. By applying the embodiment of the invention, the route configuration of a relay protection service can be optimized.

Datapath placement defines tiers for placement sets of a cell cluster, assigns cells to the tiers constrained by the datapath width, and then orders cells within each tier. Clusters are identified using machine-learning based datapath extraction. Datapath width is determined by computing a size of a bounding box for cells in the cluster. Placement sets are identified using a breadth-first search beginning with input cells for the cluster. Tiers are initially defined using logic depth assignment. A cell may be assigned to a tier by pulling the cell from the next higher tier to fill an empty location or by pushing an excess cell into the next higher tier. Cells are ordered within each tier using greedy cell assignment according to a wirelength cost function. The datapath placement can be part of an iterative process which applies spreading constraints to the cluster based on computed congestion information.

The invention provides a method for physically implementing a special integrated circuit chip under deep sub-micron. The method mainly comprises the following steps of: 1) planning layout; 2) laying out; 3) generating a clock tree; 4) wiring; and 5) extracting parameters and analyzing a static time sequence: extracting a parasitic parameter of the layout by adopting a parasitic parameter extraction tool, analyzing the static time sequence, and searching a key path according to the Breadth first search principle. The method has been applied to the practical chip developing process, passed practical tests, and has good practical using effect.

A system analyzer and a method for analyzing an impact of a change in a component of a distributed control system (DCS) are disclosed. The system can collect and store data representing the DCS components and their interconnection as well as signals of the DCS components. The DCS can be graphically modeled with nodes and directed edges, wherein a node represents either a type of DCS component or a signal of a DCS components, and wherein an edge is an “influence”-edge, or a “contains”-edge. Information on a change of a DCS components is received, a depth first or breadth first search is performed over the “influence”-edges and “contains”-edges and determine unchanged DCS components which would be affected by a malfunction, a removal or a taking out of operation of the at least one DCS component, and information on the affected DCS components is transmitted to an operator interface.

The invention provides a robot path planning method and system based on skeleton extraction of a passable area. The method comprises the following steps of constructing an environment grid map, and projecting an initial position of a robot, an obstacle and a target position into the grid map; determining the passable area of the robot in the grid map, and then performing skeleton extraction on thepassable area by using a Zhang-Suen algorithm; positioning a path start point and an end point to the grid map, designing an eight-neighborhood grid state of the grid map, so that a grid point wherethe path start point and the end point are located can be reserved as a skeleton point in a passable area refinement process; and using a breadth-first search algorithm to find a shortest connected skeleton connecting the path start point and the end point to obtain a shortest path that the robot can pass. A path trajectory obtained by the method is approximately in a middle position of the passable area, the safety requirement of the robot path planning can be better met, a skeleton extraction algorithm is improved, and a skeleton extraction result retains path start point and end point information.

The invention relates to a method for converting a ladder diagram into a PLC (Programmable Logic Controller) program command, which comprises the following steps of: 1, presenting a topological structure of a ladder diagram by using a directed graph; 2, traversing a transposed graph GL <T> by using a depth-first search method, storing a topological sorting relation of parallel-connection peaks and coil peaks in a queue Q; 3, carrying out breadth-first search on the parallel-connection peaks according to a connection relation of the directed graph GL, carrying out depth-first search on serial-connection peaks adjacently connected with the parallel-connection peaks, generating an AND expression of the directed graph GL on the whole serial-connection path and an OR expression of the serial-connection peaks; 4, generating a final expression of the maximum combining item of the parallel-connection peaks; 5, carrying out breadth-first search on a connection relation graph Gp by using the Q,figuring out an OR expression of the corresponding parallel-connection peaks and verifying, finally, constructing the maximum combining item into the AND expression to form a final result; 6, judgingwhether a queue Q' is empty; and 7, processing a starting peak. The invention can be widely applied to the process of converting the ladder diagram into the PLC program command.