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Some properties of a multidigraph by semi-incidence matrices

Ernesto Dedò, Livio Porcu
1985 Discrete Mathematics  
In this paper we determine, by two simple matrices, the expansion of the characteristic polynomial of the matrices A, A + A+, A +A-, A--A, A+-A of a multidigraph, and we obtain some interesting consequences  ...  We obtain new results and also new simple proofs of known theorems. * Research partially supported by Italian M.P.I. 0012-365X035/$3.30 0 1985, Elsevier Science Publishers B.V. (North-Holland)  ...  , we call M' and M-semi-incidence matrices (out-incidence and inincidence, respectively).  ... 
doi:10.1016/s0012-365x(85)80016-9 fatcat:e6pbwnx3gzfwpmmpgpkwemrgzi

Page 1165 of Mathematical Reviews Vol. , Issue 87c [page]

1987 Mathematical Reviews  
Entringer (Albuquerque, N.M.) 87c:05083 Dedd, Ernesto (I-MILANP); Porcu, Livio (I-MILANP) Some properties of a multidigraph by semi-incidence matrices. Discrete Math. 55 (1985), no. 1, 1-11.  ...  The n x m matrices Mt = (mi) and M~ = (m;;) are called the semi-incidence ma- trices of [. Clearly, M+ — M~ =: D and M+ + M~ =: X are the ordinary incidence matrices of [ and G, respectively.  ... 

Error Floor Approximation for LDPC Codes in the AWGN Channel [article]

Brian K. Butler, Paul H. Siegel
2013 arXiv   pre-print
We develop a refined linear model, based on the work of Sun and others, that accurately predicts error floors caused by elementary tapping sets for saturating decoders.  ...  We employ an LLR-domain SPA decoder that does not saturate near-certain messages and find the error rates of our decoder to be lower by at least several orders of magnitude.  ...  Further, the authors are indebted to Xiaojie Zhang for verifying several of our low floor results in the AWGN channel with an independent implementation of the non-saturating SPA decoder.  ... 
arXiv:1202.2826v2 fatcat:4a7u4qhrojcsfhhclhfbsc4r3y

Non-negative spectrum of a digraph

Irena M. Jovanović
2016 Ars Mathematica Contemporanea  
The common spectrum of these matrices is called non-negative spectrum or N -spectrum of a digraph. Several properties of the N -spectrum are proved.  ...  Digraphs are considered by means of eigenvalues of the matrix AA T , and similarly A T A, where A is the adjacency matrix of a digraph.  ...  The in-incidence matrix of D is the n by m matrix B in = [b ij ] such that b ij = 1 if e j = (v k , v i ) for some vertex v k , and otherwise b ij = 0.  ... 
doi:10.26493/1855-3974.682.065 fatcat:uawix25wtza57pbm352ggjmfsq

Seidel switching for weighted multi-digraphs and its quantum perspective [article]

Supriyo Dutta, Bibhas Adhikari, Subhashish Banerjee
2016 arXiv   pre-print
From a matrix theoretic point of view, Seidel switching is a combined action of a number of unitary operations on graphs.  ...  Corresponding to Laplacian matrices of any graph there are quantum states useful in quantum computing.  ...  Acknowledgement This work is partly supported by the project Graph Theoretical Aspects of Quantum Information Processing (Project No. 25(0210)/13/EMR-II) funded by the Council of Science and Industrial  ... 
arXiv:1608.07830v1 fatcat:flz3byqxqvg55gkpmy3v2pqbfy

Graph spectral techniques in computer sciences

Branko Arsic, Dragos Cvetkovic, Slobodan Simic, Milan Skaric
2012 Applicable Analysis and Discrete Mathematics  
We give a survey of graph spectral techniques used in computer sciences.  ...  The survey consists of a description of particular topics from the theory of graph spectra independently of the areas of Computer science in which they are used.  ...  The authors are grateful to the referees for the many useful comments and suggestions which have led to an improvement of this paper. Sup-  ... 
doi:10.2298/aadm111223025a fatcat:msxavfozrzddlc5ipbcbw7ithu

Eigenvalues of Cayley graphs [article]

Xiaogang Liu, Sanming Zhou
2019 arXiv   pre-print
We survey some of the known results on eigenvalues of Cayley graphs and their applications, together with related results on eigenvalues of Cayley digraphs and generalizations of Cayley graphs.  ...  An incident point-block pair of D is usually called a flag of D.  ...  from D by interchanging the roles of points and blocks but retaining the incidence relation.  ... 
arXiv:1809.09829v2 fatcat:57hq3pcaurhybgfuzzh6qi74nu

Page 261 of Mathematical Reviews Vol. , Issue Index [page]

Mathematical Reviews  
Smith) 87f:17001 17A05 Dedd, Ernesto (with Porcu, Livio) Some properties of a multidigraph by semi-incidence matrices. Discrete Math. 55 (1985), no. 1, 1-11. (H.  ...  (Andor Dobé) 87g:60076b 60K15 (60K20, 62P05) (with Manca, Raimondo) Some new results on the transient behaviour of semi-Markov reward processes.  ... 

Matrix Zoom: A Visual Interface to Semi-External Graphs

J. Abello, F. van Ham
IEEE Symposium on Information Visualization  
This is achieved by providing a zoomable matrix view of the underlying data. This view is strongly coupled to a hierarchical view of the essential information elements present in the data domain.  ...  We illustrate the applicability of this work to the visual navigation of cancer incidence data and to an aggregated sample of phone call traffic.  ...  Stephen Kobourov and Sandra Sudarsky entertained some discussions related to graph peeling.  ... 
doi:10.1109/infvis.2004.46 dblp:conf/infovis/AbelloH04 fatcat:3gjciv2irrebjbqr4n4ms4evdi

Page 1017 of Mathematical Reviews Vol. , Issue Index [page]

Mathematical Reviews  
(Summary) 87f:68026 68Q10 (03B25, 03B70, 68Q50) Porcu, Livio (with Dedd, Ernesto) Some properties of a multidigraph by semi-incidence matrices. Discrete Math. 55 (1985), no. 1, 1-11. (H.  ...  (See 87d:00009) § 26B25 Popovsky, Otta Modeling of a system by means of time Petri nets. (Czech. English summary) Ekonom.-Mat. Obzor 22 (1986), no. 1, 88-98.  ... 

Subject Index Volumes 1–200

2001 Discrete Mathematics  
, 592 semi group, 353 i-space, 1811 semi Laguerre 1-structure, 1627 n-structure, 1811 semi Minkowski n-structure, 1811 n-regular factor, 5642 semi P 4 -sparse, 5247 graph, 5247, 5250 semi partial  ...  claw free graph, 5687 a graph, 4120 triangle incident with a 3-vertex, 4831 inequality, 1285, 4129, 4171, 4445 number of a vertex, 4794 of maximal area, 1312 rounded, 2986 sequence, 4041 structure  ...  algebra, 325 radio astronomy, 1771 radius, 2449, 2695, 2696, 3580, 3804, 3878, 4520, 4633, 5056 , 5594 radius of a bridged graph, 2465 a chordal graph, 2465 a graph, 99, 5594 a simple block, 1038 convergence  ... 
doi:10.1016/s0012-365x(00)00471-4 fatcat:znxg54q6ifgutnhzj3urcw455y

Grammatical Evolution of Technical Processes

Tino Stanković, Kristina Shea, Mario Štorga, Dorian Marjanović
2009 Volume 8: 14th Design for Manufacturing and the Life Cycle Conference; 6th Symposium on International Design and Design Education; 21st International Conference on Design Theory and Methodology, Parts A and B   unpublished
the properties of a technical system considered.  ...  Operand or effect depending on the value of type property. FlowArrow Inherits BaseArrow Bag of arcs , Incidence matrix Table 6.1, : → , Definition 6.2.  ... 
doi:10.1115/detc2009-87042 fatcat:f7ta7lv6d5a3diz6e7a6bpggsi

Italian Journal of Pure and Applied Mathematics EDITOR-IN-CHIEF Piergiulio Corsini Editorial Board F O R U M EDITOR-IN-CHIEF VICE-CHIEFS Italian Journal of Pure and Applied Mathematics EDITOR-IN-CHIEF Vice-CHIEFS Managing Board Editorial Board Italian Journal of Pure and Applied Mathematics-N. 31-2013

Saeid Abbasbandy, Reza Ameri, Luisa Arlotti, Krassimir Atanassov, Malvina Baica, Federico Bartolozzi, Rajabali Borzooei, Carlo Cecchini, Gui-Yun Chen, Domenico Chillemi, Stephen Comer, Irina Cristea (+201 others)
2013 unpublished
This work was completed while the corresponding author was a visitor at the School of Mathematical Sciences, Dublin Institute of Technology. The author would like to thank Prof. B.  ...  The author is grateful to professor A. Moudafi for his helpful comments and suggestions.  ...  This redefinition does not change properties the graph determined by an adjacent and an incidence of its vertices and edges.  ... 

On some covering, partition and connectivity problems in graphs [article]

Davis Issac, Universität Des Saarlandes, Universität Des Saarlandes
While proving the results on STC, we also make some contributions to the related area of connected partitioning.  ...  We prove the conjecture for a special class of graphs, namely squares of 2-trees, and show that square graphs are important in connection with Hadwiger's conjecture.  ...  The proof by Chen et al. was an extension of the techniques from homology used by Lovász, and hence also non-constructive.  ... 
doi:10.22028/d291-29620 fatcat:vak7wpgik5g7decytxzamky3vy

On subgroups and Schreier graphs of finitely generated groups

Paul-Henry Leemann, Tatiana Smirnova-Nagnibeda
Whereas it is easy to understand convergence and limits of transitive graphs, the notion of limit of a sequence of arbitrary graphs is more complicated -as defined by Benjamini and Schramm it is an invariant  ...  This thesis concerns combinatorial and geometric group theory -the interplay between the properties of groups and those of the geometric objects on which they act.  ...  Je remercie chaleureusement Laurent Bartholdi, Vadim Kaimanovich and Anders Karlsson de me faire l'honneur de participer à mon jury et d'avoir à plusieurs reprises pris le temps de m'écouter parler.  ... 
doi:10.13097/archive-ouverte/unige:87976 fatcat:svamdnlx4bhqto6k2dkrdncnmi