Browsing by Subject "Graph theory"
Now showing items 120 of 414

3colorability of pseudotriangulations
(2015)
Article
Open AccessDeciding 3colorability for general plane graphs is known to be an NPcomplete problem. However, for certain families of graphs, like triangulations, polynomial time algorithms exist. We consider the family of pseudotri ... 
3D point cloud video segmentation oriented to the analysis of interactions
(Institute of Electrical and Electronics Engineers (IEEE), 2016)
Conference lecture
Open AccessGiven the widespread availability of point cloud data from consumer depth sensors, 3D point cloud segmentation becomes a promising building block for high level applications such as scene understanding and interaction ... 
4labelings and grid embeddings of plane quadrangulations
(20090603)
External research report
Open AccessWe show that each quadrangulation on $n$ vertices has a closed rectangle of influence drawing on the $(n2) \times (n2)$ grid. Further, we present a simple algorithm to obtain a straightline drawing of a quadrangulation ... 
Abelian Cayley digraphs with asymptotically large order for any given degree
(20160429)
Article
Open AccessAbelian Cayley digraphs can be constructed by using a generalization to Z(n) of the concept of congruence in Z. Here we use this approach to present a family of such digraphs, which, for every fixed value of the degree, ... 
A block algorithm for the algebraic path problem and its execution on a systolic array
(Institute of Electrical and Electronics Engineers (IEEE), 1989)
Conference report
Open AccessThe solution of the algebraic path problem (APP) for arbitrarily sized graphs by a fixedsize systolic array processor (SAP) is addressed. The APP is decomposed into two subproblems, and SAP is designed for each one. Both ... 
A Boolean algebra approach to the construction of snarks
(John Wiley & Sons, 1991)
Part of book or chapter of book
Open AccessThis work deals with the construction of snarks, that is, cubic graphs that cannot be 3edgecolored. A natural generalization of the concept of "color", that describes in a simple way the coloring ("0" or "1") of any set ... 
A construction of Small (q1)Regular Graphs of Girth 8
(20150421)
Article
Open AccessIn this note we construct a new infinite family of (q  1)regular graphs of girth 8 and order 2q(q  1)(2) for all prime powers q >= 16, which are the smallest known so far whenever q  1 is not a prime power or a prime ... 
A construction of small regular bipartite graphs of girth 8
(200901)
Article
Open AccessLet q be a prime a power and k an integer such that 3 ≤ k ≤ q. In this paper we present a method using Latin squares to construct adjacency matrices of kregular bipartite graphs of girth 8 on $2(kq^{2}q)$ vertices. Some ... 
Active learning in Crowdsourcing classification problems using Sampling Theory for graph signals
(Universitat Politècnica de Catalunya, 20170515)
Bachelor thesis
Open Access
Covenantee: University of Southern California 
Acyclic choosability of planar graphs
(20100610)
Audiovisual
Open Access 
A differential approach for bounding the index of graphs under perturbations
(201103)
External research report
Open Access 
A discussion on the design of graph database benchmarks
(2011)
Article
Open AccessGraph Database Management systems (GDBs) are gaining popularity. They are used to analyze huge graph datasets that are naturally appearing in many application areas to model interrelated data. The objective of this paper ... 
Adjacency matrices of polarity graphs and of other C4free graphs of large size
(2010)
Article
Restricted access  publisher's policyIn this paper we give a method for obtaining the adjacency matrix of a simple polarity graph $G_q$ from a projective plane PG(2,q), where q is a prime power. Denote by ex(n;C₄) the maximum number of edges of a graph on n ... 
A family of mixed graphs with large order and diameter 2
(201702)
Article
Open AccessA mixed regular graph is a connected simple graph in which each vertex has both a fixed outdegree (the same indegree) and a fixed undirected degree. A mixed regular graphs is said to be optimal if there is not a mixed ... 
A framework for building OLAP cubes on graphs
(Springer, 2015)
Conference report
Open AccessGraphs are widespread structures providing a powerful abstraction for modeling networked data. Large and complex graphs have emerged in various domains such as social networks, bioinformatics, and chemical data. However, ... 
AGAMOS: A graphbased approach to modulo scheduling for clustered microarchitectures
(200906)
Article
Open AccessThis paper presents AGAMOS, a technique to modulo schedule loops on clustered microarchitectures. The proposed scheme uses a multilevel graph partitioning strategy to distribute the workload among clusters and reduces the ... 
A graph semantics for a variant of the ambient calculus more adequate for modeling SOC
(20170207)
External research report
Open AccessIn this paper we present a graph semantics of a variant of the well known ambient calculus. The main change of our variant is to extract the mobility commands of the original calculus from the ambient topology. Similar ... 
Algebraic characteritzacions of bipartite distanceregular graphs
(20100610)
Audiovisual
Open Access 
Algebraic characterizations of distanceregular graphs
(Elsevier, 2002)
Article
Open AccessWe survey some old and some new characterizations of distanceregular graphs, which depend on information retrieved from their adjacency matrix. In particular, it is shown that a regular graph with d+1 distinct eigenvalues ... 
Algebraic Characterizations of Regularity Properties in Bipartite Graphs
(2013)
Article
Restricted access  publisher's policyRegular and distanceregular characterizations of general graphs are wellknown. In particular, the spectral excess theorem states that a connected graph GG is distanceregular if and only if its spectral excess (a number ...