Paulo Boaventura Netto - Academia.edu (original) (raw)

Papers by Paulo Boaventura Netto

Research paper thumbnail of Exhaustive and metaheuristic exploration of two new structural irregularity measures

This paper presents the results of two explorations: one, exhaustive, of the graph sets from 4 to... more This paper presents the results of two explorations: one, exhaustive, of the graph sets from 4 to 10 vertices, and other, using AGX-III program on graphs from 11 to 30 vertices, both looking for extremal graphs for two new irregularity measures. Some discussions on the obtained results are presented. The involved measures have polynomial complexity.

Bookmarks Related papers MentionsView impact

Research paper thumbnail of P-antiregular graphs

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Uma revis�o comentada das abordagens do problema quadr�tico de aloca��o

Pesquisa Operacional, 2004

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Irregularidad de grafos: Discusión, extensiones de grafos y nuevas propuestas

Revista de Matemática: Teoría y Aplicaciones, 2015

This paper presents some measures of graph irregularity found in the literature. From their discu... more This paper presents some measures of graph irregularity found in the literature. From their discussion two important points appear: first, the absence of relationship between all of them, but a single exception, with the structures of the corresponding graphs and, moreover, their known extremal values correspond to graphs having degree sequences with few different values. Two new measures are proposed, seeking to meet these points. Their values are calculated for extremal graphs associated with other measures and for antiregular graphs. Finally, we calculate the boxplots of all these measures for some sets of graphs taken from the literature and also for four sets where the ordered degree sequences are constant. All measures involved have polynomial complexity.

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Um Estudo Sobre a Construção De Um Algoritmo VNS Para O Problema Quadrático De Alocação

The definition of a multiple-neighborhood structure on the permutation lattice graph is used in t... more The definition of a multiple-neighborhood structure on the permutation lattice graph is used in the study of a variable neighborhood search (VNS) algorithm applied to the Quadratic Assignment Problem.

Bookmarks Related papers MentionsView impact

Research paper thumbnail of A criterion of importance for the links of a graph: the value of spanning arborescences or trees using a given link

A previous result derived for non-valued graphs is generalized for link-valued ones, thus allowin... more A previous result derived for non-valued graphs is generalized for link-valued ones, thus allowing the determination of the total value of the spanning arborescences with a given root and containing a given arc in a directed valued graph. A corresponding result for non-directed valued graphs is also presented.

Bookmarks Related papers MentionsView impact

Research paper thumbnail of The enumeration of spanning arborescences and trees associated to a given link: an application to the enumeration of linear arborescences and trees

A result based on the matrix-tree theorem allowed us, in a previous work, to associate to a graph... more A result based on the matrix-tree theorem allowed us, in a previous work, to associate to a graph link the value of the spanning arborescences or trees from which it participates, in a directed or undirected valued graph. It is well known that for every combinatorial counting function we can define a corresponding generating function and vice-versa. Using the same techniques of the preceding work, we define a generating function for the above referred subsets of structures and use the result, together with a specific value criterion, to identify and count the linear structures.

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Alocação De Unidades Urbanas De Lazer Por Um Modelo De P-Medianas

O problema das p -medianas, que consiste em localizar p facilidades (medianas) em uma rede, minim... more O problema das p -medianas, que consiste em localizar p facilidades (medianas) em uma rede, minimizando-se a soma de todas as distâncias de cada ponto de demanda a sua mediana mais proxima, tem sido utilizado como uma ferramenta que auxilia na tomada de decisoes de localizacao. Este estudo busca localizar, atraves deuma heuristica especificamente projetada, um dado numero de unidades urbanas de lazer (largos, pracas, pracas esportivas, pocket parks , bosques e parques municipais), em uma area da regiao norte do Rio de Janeiro. Palavras-chave: p-medianas, Unidades Urbanas de Lazer, grafos.

Bookmarks Related papers MentionsView impact

Research paper thumbnail of O Problema Da Alocação Dinâmica De Espaços: Aplicação Das Metaheurísticas Grasp e Busca Tabu

Resumo Neste trabalho é abordado o Problema da Alocação Dinâmica de Espaços onde um projeto é div... more Resumo Neste trabalho é abordado o Problema da Alocação Dinâmica de Espaços onde um projeto é dividido por um número de períodos consecutivos e, em cada um deles, uma quantidade de atividades é realizada. Os recursos necessários para as atividades devem estar disponíveis em espaços de trabalho e os recursos ociosos no período devem ser guardados em espaços de armazenamento. Este problema contém o Problema Quadrático de Alocação (PQA) como um caso particular e, portanto, pertence a classe NP-difícil. Neste contexto a dificuldade em encontrar soluções ótimas, mesmo para instâncias de média dimensão, justifica o uso de métodos heurísticos. Este trabalho propõe algoritmos de construção e heurísticas baseados no GRASP e Busca Tabu para a obtenção de soluções aproximadas. Os resultados computacionais obtidos mostram que os métodos propostos são competitivos na resolução das instâncias do problema existentes na literatura. Abstract This work is dedicated to the Dynamic Space Allocation Pro...

Bookmarks Related papers MentionsView impact

Research paper thumbnail of O uso das variâncias do PQA na caracterização do isomorfismo de grafos

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Ranking graph edges by the weight of their spanning arborescences or trees

Pesquisa Operacional, 2008

A result based on a classic theorem of graph theory is generalized for edge-valued graphs, allowi... more A result based on a classic theorem of graph theory is generalized for edge-valued graphs, allowing determination of the total value of the spanning arborescences with a given root and containing a given arc in a directed valued graph. A corresponding result for undirected valued graphs is also presented. In both cases, the technique allows for a ranking of the graph edges by importance under this criterion. This ranking is proposed as a tool to determine the relative importance of the edges of a graph in network vulnerability studies. Some examples of application are presented.

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Geração de seqüências viáveis para montagem automatizada

Produção, 1993

Este trabalho consiste numa aplicação das técnicas de modelagem por grafos à geração de seqüência... more Este trabalho consiste numa aplicação das técnicas de modelagem por grafos à geração de seqüências de montagem de um produto discreto (composto de uma série de peças). Utilizamos como referência para o trabalho método desenvolvido por A. Bourjault [5] e T. Fazio e D. Whitney [6].

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Contribuição Ao Projeto e À Crítica De Redes Metroviárias: Uma Aplicação De Grafos

A vertex-set covering in a triangulated planar su pport graph is built as a se t of elementary pa... more A vertex-set covering in a triangulated planar su pport graph is built as a se t of elementary paths between pairs of peripherical vertices, with the restriction of maximum degree 4 for the spanning subgraph thus obtained. This structure is what one would need when designing a metro network, where the vertices are the stations and the edges are line

Bookmarks Related papers MentionsView impact

Research paper thumbnail of The dynamic space allocation problem: Applying hybrid GRASP and Tabu search metaheuristics

Computers & Operations Research, 2012

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Contribuição Para O Projeto De Eletrificação De Zonas Rurais: Uma Aplicação De Grafos

Given a support planar graph representing points to receive electric charge (charge points) and e... more Given a support planar graph representing points to receive electric charge (charge points) and every possible link able to be built in a real estate region, the objective of this work is the development of a heuristic for generating a least-cost distributiom network taking into account the technical, environmental and operational constraints associated to the problem. For such a situation

Bookmarks Related papers MentionsView impact

Research paper thumbnail of An analytical survey for the quadratic assignment problem

European Journal Operational …, 2007

The quadratic assignment problem (QAP), one of the most difficult problems in the NP-hard class, ... more The quadratic assignment problem (QAP), one of the most difficult problems in the NP-hard class, models many applications in several areas such as operational research, parallel and distributed computing, and combinatorial data analysis. Other optimization combinatorial problems such as the traveling salesman problem, maximal clique, isomorphism and graph partitioning can be formulated as a QAP. In this paper, we survey

Bookmarks Related papers MentionsView impact

Research paper thumbnail of GRASP para o PQA: um limite de aceitação para soluções iniciais

Pesquisa Operacional, 2000

O Problema Quadrático de Alocação (PQA) pertence à classe dos problemas NP-Hard e desafia os pesq... more O Problema Quadrático de Alocação (PQA) pertence à classe dos problemas NP-Hard e desafia os pesquisadores tanto em sua teoria quanto em sua parte computacional. Pela sua alta complexidade muitos métodos heurísticos têm sido desenvolvidos para tentar resolvê-lo aproximadamente. A metaheurística GRASP (greedy randomized adaptive search procedures) se mostrou bastante eficiente. Neste trabalho, uma proposta para descartar soluções iniciais supostamente ruins é apresentada com base na normalização de custos calculadas num intervalo entre limites de solução. Para este GRASP restrito, foi observada uma redução do tempo computacional para encontrar as soluções ótimas ou soluções viáveis de boa qualidade quando comparado ao GRASP original.

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Efficient Metaheuristics For The Dynamic Space Allocation Problem

Anais do 10. Congresso Brasileiro de Inteligência Computacional, 2016

Bookmarks Related papers MentionsView impact

Research paper thumbnail of QAPV: a polynomial invariant for graph isomorphism testing

Pesquisa Operacional, 2013

Bookmarks Related papers MentionsView impact

Research paper thumbnail of A survey for the quadratic assignment problem

European Journal of Operational Research, 2007

The quadratic assignment problem (QAP), one of the most difficult problems in the NP-hard class, ... more The quadratic assignment problem (QAP), one of the most difficult problems in the NP-hard class, models many real-life problems in several areas such as facilities location, parallel and distributed computing, and combinatorial data analysis. Combinatorial optimization ...

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Exhaustive and metaheuristic exploration of two new structural irregularity measures

This paper presents the results of two explorations: one, exhaustive, of the graph sets from 4 to... more This paper presents the results of two explorations: one, exhaustive, of the graph sets from 4 to 10 vertices, and other, using AGX-III program on graphs from 11 to 30 vertices, both looking for extremal graphs for two new irregularity measures. Some discussions on the obtained results are presented. The involved measures have polynomial complexity.

Bookmarks Related papers MentionsView impact

Research paper thumbnail of P-antiregular graphs

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Uma revis�o comentada das abordagens do problema quadr�tico de aloca��o

Pesquisa Operacional, 2004

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Irregularidad de grafos: Discusión, extensiones de grafos y nuevas propuestas

Revista de Matemática: Teoría y Aplicaciones, 2015

This paper presents some measures of graph irregularity found in the literature. From their discu... more This paper presents some measures of graph irregularity found in the literature. From their discussion two important points appear: first, the absence of relationship between all of them, but a single exception, with the structures of the corresponding graphs and, moreover, their known extremal values correspond to graphs having degree sequences with few different values. Two new measures are proposed, seeking to meet these points. Their values are calculated for extremal graphs associated with other measures and for antiregular graphs. Finally, we calculate the boxplots of all these measures for some sets of graphs taken from the literature and also for four sets where the ordered degree sequences are constant. All measures involved have polynomial complexity.

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Um Estudo Sobre a Construção De Um Algoritmo VNS Para O Problema Quadrático De Alocação

The definition of a multiple-neighborhood structure on the permutation lattice graph is used in t... more The definition of a multiple-neighborhood structure on the permutation lattice graph is used in the study of a variable neighborhood search (VNS) algorithm applied to the Quadratic Assignment Problem.

Bookmarks Related papers MentionsView impact

Research paper thumbnail of A criterion of importance for the links of a graph: the value of spanning arborescences or trees using a given link

A previous result derived for non-valued graphs is generalized for link-valued ones, thus allowin... more A previous result derived for non-valued graphs is generalized for link-valued ones, thus allowing the determination of the total value of the spanning arborescences with a given root and containing a given arc in a directed valued graph. A corresponding result for non-directed valued graphs is also presented.

Bookmarks Related papers MentionsView impact

Research paper thumbnail of The enumeration of spanning arborescences and trees associated to a given link: an application to the enumeration of linear arborescences and trees

A result based on the matrix-tree theorem allowed us, in a previous work, to associate to a graph... more A result based on the matrix-tree theorem allowed us, in a previous work, to associate to a graph link the value of the spanning arborescences or trees from which it participates, in a directed or undirected valued graph. It is well known that for every combinatorial counting function we can define a corresponding generating function and vice-versa. Using the same techniques of the preceding work, we define a generating function for the above referred subsets of structures and use the result, together with a specific value criterion, to identify and count the linear structures.

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Alocação De Unidades Urbanas De Lazer Por Um Modelo De P-Medianas

O problema das p -medianas, que consiste em localizar p facilidades (medianas) em uma rede, minim... more O problema das p -medianas, que consiste em localizar p facilidades (medianas) em uma rede, minimizando-se a soma de todas as distâncias de cada ponto de demanda a sua mediana mais proxima, tem sido utilizado como uma ferramenta que auxilia na tomada de decisoes de localizacao. Este estudo busca localizar, atraves deuma heuristica especificamente projetada, um dado numero de unidades urbanas de lazer (largos, pracas, pracas esportivas, pocket parks , bosques e parques municipais), em uma area da regiao norte do Rio de Janeiro. Palavras-chave: p-medianas, Unidades Urbanas de Lazer, grafos.

Bookmarks Related papers MentionsView impact

Research paper thumbnail of O Problema Da Alocação Dinâmica De Espaços: Aplicação Das Metaheurísticas Grasp e Busca Tabu

Resumo Neste trabalho é abordado o Problema da Alocação Dinâmica de Espaços onde um projeto é div... more Resumo Neste trabalho é abordado o Problema da Alocação Dinâmica de Espaços onde um projeto é dividido por um número de períodos consecutivos e, em cada um deles, uma quantidade de atividades é realizada. Os recursos necessários para as atividades devem estar disponíveis em espaços de trabalho e os recursos ociosos no período devem ser guardados em espaços de armazenamento. Este problema contém o Problema Quadrático de Alocação (PQA) como um caso particular e, portanto, pertence a classe NP-difícil. Neste contexto a dificuldade em encontrar soluções ótimas, mesmo para instâncias de média dimensão, justifica o uso de métodos heurísticos. Este trabalho propõe algoritmos de construção e heurísticas baseados no GRASP e Busca Tabu para a obtenção de soluções aproximadas. Os resultados computacionais obtidos mostram que os métodos propostos são competitivos na resolução das instâncias do problema existentes na literatura. Abstract This work is dedicated to the Dynamic Space Allocation Pro...

Bookmarks Related papers MentionsView impact

Research paper thumbnail of O uso das variâncias do PQA na caracterização do isomorfismo de grafos

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Ranking graph edges by the weight of their spanning arborescences or trees

Pesquisa Operacional, 2008

A result based on a classic theorem of graph theory is generalized for edge-valued graphs, allowi... more A result based on a classic theorem of graph theory is generalized for edge-valued graphs, allowing determination of the total value of the spanning arborescences with a given root and containing a given arc in a directed valued graph. A corresponding result for undirected valued graphs is also presented. In both cases, the technique allows for a ranking of the graph edges by importance under this criterion. This ranking is proposed as a tool to determine the relative importance of the edges of a graph in network vulnerability studies. Some examples of application are presented.

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Geração de seqüências viáveis para montagem automatizada

Produção, 1993

Este trabalho consiste numa aplicação das técnicas de modelagem por grafos à geração de seqüência... more Este trabalho consiste numa aplicação das técnicas de modelagem por grafos à geração de seqüências de montagem de um produto discreto (composto de uma série de peças). Utilizamos como referência para o trabalho método desenvolvido por A. Bourjault [5] e T. Fazio e D. Whitney [6].

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Contribuição Ao Projeto e À Crítica De Redes Metroviárias: Uma Aplicação De Grafos

A vertex-set covering in a triangulated planar su pport graph is built as a se t of elementary pa... more A vertex-set covering in a triangulated planar su pport graph is built as a se t of elementary paths between pairs of peripherical vertices, with the restriction of maximum degree 4 for the spanning subgraph thus obtained. This structure is what one would need when designing a metro network, where the vertices are the stations and the edges are line

Bookmarks Related papers MentionsView impact

Research paper thumbnail of The dynamic space allocation problem: Applying hybrid GRASP and Tabu search metaheuristics

Computers & Operations Research, 2012

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Contribuição Para O Projeto De Eletrificação De Zonas Rurais: Uma Aplicação De Grafos

Given a support planar graph representing points to receive electric charge (charge points) and e... more Given a support planar graph representing points to receive electric charge (charge points) and every possible link able to be built in a real estate region, the objective of this work is the development of a heuristic for generating a least-cost distributiom network taking into account the technical, environmental and operational constraints associated to the problem. For such a situation

Bookmarks Related papers MentionsView impact

Research paper thumbnail of An analytical survey for the quadratic assignment problem

European Journal Operational …, 2007

The quadratic assignment problem (QAP), one of the most difficult problems in the NP-hard class, ... more The quadratic assignment problem (QAP), one of the most difficult problems in the NP-hard class, models many applications in several areas such as operational research, parallel and distributed computing, and combinatorial data analysis. Other optimization combinatorial problems such as the traveling salesman problem, maximal clique, isomorphism and graph partitioning can be formulated as a QAP. In this paper, we survey

Bookmarks Related papers MentionsView impact

Research paper thumbnail of GRASP para o PQA: um limite de aceitação para soluções iniciais

Pesquisa Operacional, 2000

O Problema Quadrático de Alocação (PQA) pertence à classe dos problemas NP-Hard e desafia os pesq... more O Problema Quadrático de Alocação (PQA) pertence à classe dos problemas NP-Hard e desafia os pesquisadores tanto em sua teoria quanto em sua parte computacional. Pela sua alta complexidade muitos métodos heurísticos têm sido desenvolvidos para tentar resolvê-lo aproximadamente. A metaheurística GRASP (greedy randomized adaptive search procedures) se mostrou bastante eficiente. Neste trabalho, uma proposta para descartar soluções iniciais supostamente ruins é apresentada com base na normalização de custos calculadas num intervalo entre limites de solução. Para este GRASP restrito, foi observada uma redução do tempo computacional para encontrar as soluções ótimas ou soluções viáveis de boa qualidade quando comparado ao GRASP original.

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Efficient Metaheuristics For The Dynamic Space Allocation Problem

Anais do 10. Congresso Brasileiro de Inteligência Computacional, 2016

Bookmarks Related papers MentionsView impact

Research paper thumbnail of QAPV: a polynomial invariant for graph isomorphism testing

Pesquisa Operacional, 2013

Bookmarks Related papers MentionsView impact

Research paper thumbnail of A survey for the quadratic assignment problem

European Journal of Operational Research, 2007

The quadratic assignment problem (QAP), one of the most difficult problems in the NP-hard class, ... more The quadratic assignment problem (QAP), one of the most difficult problems in the NP-hard class, models many real-life problems in several areas such as facilities location, parallel and distributed computing, and combinatorial data analysis. Combinatorial optimization ...

Bookmarks Related papers MentionsView impact