1,721,021 research outputs found
Spectral properties of matrices and graphs
No full textMatrices and graphs are characterized by their spectral properties. Useful information on graps can be deumed by their associated matrices, while, on the other hand, many interesting results on matrices can be proved by using their associated graph structure, Through some spectral bounds, conditions for connectivity and estimates for some invariant measures of a non oriented graph will be obtained
Lecture Notes in Economics and Mathematical Systems: Preface
No full textThe volume, devoted to recent contributions to the field of networks modelling, offers a wide panorama of recent advances, both theoretical and methodological, that will interest academics as well as practitioners. Theory and applications are nicely integrated: theoretical papers are in graph theory, game theory, coalitions, dynamics, consumer behaviour, segregation models and new contributions to the area are offered. The applications cover a wide range: airline transportation, financial markets, work team organization, labour and credit market. The volume can be used as a reference book for graduate and postgraduate courses on network theory and complex systems in faculties of economics, mathematics, engineering or social sciences
Betweenness centrality: extremal values and structural properties
No full textIn this paper we investigate the structural properties of betweenness centrality and determine some cases in which betweenness reaches its extremal values. Special attention is paid to Star(G), the set of vertices adjacent to all other vertices in a graph and we prove several results about the betweenness of the elements of this set. We introduce the new concept of total betweenness and relate it to group betweenness. We prove a necessary and sufficient condition for the two measures to coincide. Next we consider cutsets and cutvertices and we find a lower bound for their betweenness; in particular for a cutvertex this lower bound is the cutting number. Finally we apply the previous results to trees, proving an alternative formula for betweenness based oil cutvertex properties
GEM (Green Energy Management) Summer School 2016
No full textThe 3rd Edition of GEM (Green Energy Management) Summer School is
taking place in Erice (Sicily). It aims to provide international students with a
context sensitive first-class training in the field of Green Energy
Management and renewable resources. Leading scientists from Europe
and industrial and institutional partners will be part of the teaching staff,
bringing in their expertise and experience. Visits to local research
laboratories will also be organized. The program will be held at: Ettore
Majorana Centre in Erice (Sicily); a unique location famous for its beauty,
history and scientific relevance, will provide the faculty and participants to
engage in dialogue and knowledge sharing
Limiting intervals for spectrum distribution
No full textIn this paper we determine low and upper bounds for the eigenvalues of a complex matrix A, through easy computations over the matrix elements, in particular traces of A and of its second and third power. mean, standard deviation and third centered moments of the real and imaginary parts of the spectrum distribution are introduced. particularly interesting results are obtained for matrices with real spectrum and normal matrices
Networks, Topology and Dynamics
Full text linkInterest in network analysis has grown in recent years. Many social, economic and financial systems with large numbers of interacting agents can be conveniently described by a network. In the last decade, new theories have been developed to highlight the topological properties of network architectures, despite their apparent randomness. Networks, moreover, once included in a dynamic setting, prove to be convenient mathematical tools in modeling many phenomena. This special issue of Quality and Quantity aims at providing a state–of–the–art overview of the research currently in progress at the global level, with a special focus on applications to Economics and Social Sciences
Un programma di classificazione dei titoli obbligazionari
No full textThis paper proposes an algorithm designed to classify dynamically groups of bond issues according to their maturities. In particular the main aim of teh algorithm itself is to shift automatically one issue from one maturity class to the preceding one as time goes on. Each of the maturity classes is the arranged in terms of a time series in order to get information about the yields, and subsequently analyze and compare the performance of bonds priced on the Italian Market depending on their time-to-maturity characteristics
GEM (Green Energy Management) Summer School, Astana, Kazakhstan, Agosto-Settembre 2017, in collaborazione con ENU (L.N.Gumilyov Eurasian National University, Astana, KZ)
No full textLa connessione nella teoria dei grafi:reti finanziarie e di trasporto
No full textScopo del lavoro è di analizzare le proprietà di connessione dei reti di trasporto
- …
