Results 21 to 30 of about 285 (94)

Long Memory Models to Generate Synthetic Hydrological Series

Mathematical Problems in Engineering, Volume 2014, Issue 1, 2014., 2014
In Brazil, much of the energy production comes from hydroelectric plants whose planning is not trivial due to the strong dependence on rainfall regimes. This planning is accomplished through optimization models that use inputs such as synthetic hydrologic series generated from the statistical model PAR(p) (periodic autoregressive).
Guilherme Armando de Almeida Pereira, Reinaldo Castro Souza, Nazim I. Mahmudov   +2 more
wiley   +1 more source

The logic of the valorization of natural resources in Brazil: historical relationship between the electricity sector and the mining industry in the Amazon

Novos Cadernos NAEA, 2017
O presente artigo procura traçar uma análise do ponto de vista histórico para, posteriormente, compreender a relação econômica entre os fenômenos históricos ocorridos no Governo Militar e, recentemente, no governo do ex-presidente, Luiz Inácio Lula da ...
André Cutrim Carvalho, Cleyton Alves Candeira Pimentel   +1 more
doaj   +1 more source

Nonhyperbolic Periodic Orbits of Vector Fields in the Plane Revisited

Abstract and Applied Analysis, Volume 2013, Issue 1, 2013., 2013
The main goal of this paper is to present a theory of approximation of periodic orbits of vector fields in the plane. From the theory developed here, it is possible to obtain an approximation to the curve of nonhyperbolic periodic orbits in the bifurcation diagram of a family of differential equations that has a transversal Hopf point of codimension ...
Denis de Carvalho Braga, Luis Fernando Mello, Antonio Carlos Zambroni de Souza, Sakthivel Rathinasamy   +3 more
wiley   +1 more source

S100β Levels in CSF of Nonambulatory Dogs with Intervertebral Disk Disease Treated with Electroacupuncture

Journal of Veterinary Medicine, Volume 2013, Issue 1, 2013., 2013
The aim of the study was to investigate S100β levels in the cerebrospinal fluid of nonambulatory dogs with intervertebral disk disease treated with electroacupuncture: 10 dogs with thoracolumbar disk extrusion graded 3 to 5 (EA group) and 7 dogs without neurologic dysfunction (control group). All dogs regained ambulation.
Ayne Murata Hayashi, Ana Carolina Brandão Campos Fonseca Pinto, Silvia Renata Gaido Cortopassi, Valdecir Marvulle, Jessica Ruivo Maximino, Gerson Chadi, Julia Maria Matera, Antonio Ortega-Pacheco   +7 more
wiley   +1 more source

Investigação sobre a organização do trabalho para a inovação e transição tecnológica no setor elétrico brasileiro

Gestão & Produção
Resumo: Este artigo tem como objetivo caracterizar a estrutura organizacional para a inovação em empresas do setor elétrico de acordo com a literatura relacionada à transição tecnológica e à organização do trabalho para a inovação. Por meio de estudos de
Guilherme Amaral, Roberto Marx, Mario Salerno   +2 more
doaj   +1 more source

Stochastic Dynamic Programming Applied to Hydrothermal Power Systems Operation Planning Based on the Convex Hull Algorithm

Mathematical Problems in Engineering, Volume 2010, Issue 1, 2010., 2010
This paper presents a new approach for the expected cost‐to‐go functions modeling used in the stochastic dynamic programming (SDP) algorithm. The SDP technique is applied to the long‐term operation planning of electrical power systems. Using state space discretization, the Convex Hull algorithm is used for constructing a series of hyperplanes that ...
Bruno H. Dias, André L. M. Marcato, Reinaldo C. Souza, Murilo P. Soares, Ivo C. Silva Junior, Edimar J. de Oliveira, Rafael B. S. Brandi, Tales P. Ramos, Joaquim J. Júdice   +8 more
wiley   +1 more source

Bifurcation Analysis of a Van der Pol‐Duffing Circuit with Parallel Resistor

Mathematical Problems in Engineering, Volume 2009, Issue 1, 2009., 2009
We study the local codimension one, two, and three bifurcations which occur in a recently proposed Van der Pol‐Duffing circuit (ADVP) with parallel resistor, which is an extension of the classical Chua′s circuit with cubic nonlinearity. The ADVP system presents a very rich dynamical behavior, ranging from stable equilibrium points to periodic and even ...
Denis de Carvalho Braga, Luis Fernando Mello, Marcelo Messias, Dane Quinn   +3 more
wiley   +1 more source

As velhas e as novas multinacionais: o caso da energia

Brazilian Journal of Political Economy
RESUMO As teorias atuais sobre corporações multinacionais (MNCs) e transferência de tecnologia alcançaram vários resultados! grandes avanços. Eles são resumidos esquematicamente neste trabalho como a “síntese teórica estabelecida”, resultante da ...
JORGE NIOSI, PHILIPPE FAUCHER
doaj   +1 more source

Precarização e acidentes de trabalho: os riscos da terceirização no setor elétrico

Revista Brasileira de Saúde Ocupacional, 2021
Resumo Introdução: o trabalho terceirizado no setor elétrico tem peculiaridades que demandam consideração no que concerne à segurança dos trabalhadores.
Maria Elizabeth Antunes Lima, Rodrigo Castro Oliveira   +1 more
doaj   +1 more source

Voltage collapse in power systems: Dynamical studies from a static formulation

Mathematical Problems in Engineering, Volume 2006, Issue 1, 2006., 2006
This paper addresses the problem of voltage collapse in power systems. More precisely, we exhibit a voltage collapse in a power system with two buses. This study is carried out with the help of two approaches. The first is a dynamical approach where a saddle‐node bifurcation is analyzed and the second is an algebraic approach. Both approaches deal with
Luis Fernando Mello, Antonio Carlos Zambroni de Souza, Gerson Hiroshi Yoshinari, Camila Vasconcelos Schneider   +3 more
wiley   +1 more source