China
Africa
Explore chapters and articles related to this topic
Deployment, Patrolling and Foraging
Published in Yasmina Bestaoui Sebbane, Multi-UAV Planning and Task Allocation, 2020
In order to find the optimal locations of UAVs functioning as communication relays at a fixed position between stationary nodes, the performance index for network connectivity is used. As the number of nodes increases, network complexity increases. Thus, the concept of minimum spanning tree can be used to obtain the highest probability of a successful transmission using minimum possible links. A spanning tree is a subgraph that is itself a tree connecting all the vertices of the graph together. For a successful transmission, the weight of each graph node is Wij=-logPrij
Deployment, Patrolling, and Foraging
Published in Yasmina Bestaoui Sebbane, Intelligent Autonomy of Uavs, 2018
Optimal UAV deployment for stationary nodes In order to find the optimal locations of UAVs functioning as communication relays at a fixed position between stationary nodes, the performance index for network connectivity is used. As the number of nodes increases, network complexity increases. Thus, the concept of minimum spanning tree can be used to obtain the highest probability of a successful transmission using minimum possible links. A spanning tree is a sub-graph that is itself a tree connecting all the vertices of the graph together. For a successful transmission, the weight of each graph node is Wij=-logPrij $$ \begin{aligned} W_{ij} = - log P_r^{ij} \end{aligned} $$
Information Visualization
Published in Alexandru Telea, Data Visualization, 2014
In practice, the node pair that defines an edge in a tree is ordered to encode application-specific semantics. In such cases, for an edge ei = (nj, nk), the first node (nj) is called the parent of nk and the second one (nk) is called the child of nj. Hence, a tree can be seen as a hierarchical structure of parent and child nodes. In this model, a parent node may have any number of children, but a child node can have only one parent. Given that all nodes in a tree are connected, we deduce that there is a single node in a tree that has no parents. This node is called the tree root, and represents the top level of the hierarchy encoded by the tree. Symmetrically, there are several nodes in a tree that have no children. These nodes are called leaves, and represent the bottom-most level of the hierarchy encoded by the tree. Finally, the depth of a tree is the length of the longest path (number of nodes) that connects a leaf to the root.
A new approach in developing an urban rail transit emergency knowledge graph based on operation fault logs
Published in Journal of Transportation Safety & Security, 2022
Bosong Fan, Chunfu Shao, Yutong Liu, Juan Li
A spanning tree is a subgraph of a connected graph that contains all nodes connected to as few edges as possible. A directed connected graph can be represented by its node set and directed edge set Each directed edge has a score Here, we define a MST as a directed connected graph that maximizes the sum of the scores of the node set containing the edges between particular nodes. By solving the MST, we then obtain the risk causation phrase, the emergency measure phrase, and the dependencies relations.
Robust Web Data Extraction Based on Weighted Path-layer Similarity
Published in Journal of Computer Information Systems, 2022
The target data selected by end-users usually lies in leaf nodes of the HTML tree, such as the text strings, images, videos, and more. The leaf node is a node with no child in the tree. The datatype of a leaf node in an HTML tree represents what characteristic of information it carries. For example, almost all viewable textual content in a webpage is in text nodes. The text node can be a child node of different page elements such as a paragraph element <p>, a table element <table> or a link element <a>. Without such characteristics, it would be difficult even for a human being to find the required information in page variants quickly. The datatype addresses characteristics of a leaf node through three types of information: property, affiliation and structure. Property is text, image, video, audio and others.The text is the character string in webpages such as an article. The image, video, audio are instances of multimedia files. The others are properties that are not text, image, video, or audio.
Modelling epidemics on d-cliqued graphs
Published in Letters in Biomathematics, 2018
Laura P. Schaposnik, Anlin Zhang
A rooted tree is a tree in which one vertex has been designated the root. In such trees, the parent of a vertex v is the vertex connected to it on the path to the root , and v is called a child of the parent vertex. The height is the length, in number of edges, from a terminal vertex to the root. We assume that all terminal vertices of the d-regular tree have the same height and call this the height of the d-regular tree. The network diameterL of a d-regular tree is the number of edges in the longest path between two vertices. Regular trees are closely related to d-ary trees (Figure 2).