935 resultados para PI controller
Resumo:
In the Guadalupe city, with the arrival of the Boa Esperança Hydroelectric, the landscape of the municipal district lived important transformations. Those transformations continue growing today, now together with new vectors of territorial ordering, especially the agricultural industry. In front of the context of stability-instability of the environmental systems, it original of its natural vulnerability to the instability and of the transformations in the territorial dynamics of Guadalupe, the present research it analyzed and it mapped that municipal territory with relationship to the degrees of vulnerability of the environmental systems. Therefore, working a leaning methodology in a systemic perspective of the landscape and in the geoprocessing technique, the dissertation showed with thematic mapping, the most vulnerable and less vulnerable parts of the municipal district of Guadalupe, looking for a strategic vision of the problem.
Resumo:
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Resumo:
The behavior of the transition pion form factor for processes gamma (*)gamma --> pi(0) and gamma (*)gamma (*) --> pi(0) at large values of space-like photon momenta is estimated within the nonlocal covariant quark-pion model. It is shown that, in general, the coefficient of the leading asymptotic term depends dynamically on the ratio of the constituent quark mass and the average virtuality of quarks in the vacuum and kinematically on the ratio of photon virtualities. The kinematic dependence of the transition form factor allows us to obtain the relation between the pion light-cone distribution amplitude and the quark-pion vertex function. The dynamic dependence indicates that the transition form factor gamma (*)gamma -->, pi(0) at high momentum transfers is very sensitive to the nonlocality size of nonperturbative fluctuations in the QCD vacuum. (C) 2000 Elsevier B.V. B.V. All rights reserved.
Resumo:
We report the observation of the X(3872) in the J/psipi(+)pi(-) channel, with J/psi decaying to mu(+)mu(-), in p (p) over bar collisions at roots=1.96 TeV. Using approximately 230 pb(-1) of data collected with the Run II D0 detector, we observe 522+/-100 X(3872) candidates. The mass difference between the X(3872) state and the J/psi is measured to be 774.9+/-3.1(stat)+/-3.0(syst) MeV/c(2). We have investigated the production and decay characteristics of the X(3872) and find them to be similar to those of the psi(2S) state.
Resumo:
The QCD Sum Rules have been used to evaluate the form factor in the vertex KK*pi. The method of QCD Sum Rules is based on the duality principle in which it is assumed that the hadrons can simultaneously be described in two levels: quarks and hadrons. This work showed that the, axial current, used to describe the meson K is not appropriated to study the form factor.
Resumo:
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Resumo:
The A (2)Sigma(+) and X(2)Pi electronic states of the SiP species have been investigated theoretically at a very high level of correlation treatment (CASSCF/MRSDCI). Very accurate potential energy curves are presented for both states, as well as the associated spectroscopic constants as derived from the vib-rotational energy levels determined by means of the numerical solution of the radial Schrodinger equation. Electronic transition moment function, oscillator strengths, Einstein coefficients for spontaneous emission, and Franck-Condon factors for the A(2)Sigma(+)-X(2)Pi system have been calculated. Dipole moment functions and radiative lifetimes for both states have also been determined. Spin-orbit coupling constants are also reported. The radiative lifetimes for the A(2)Sigma(+) state, taking into account the spin-orbit diagonal correction to the X(2)Pi state, decrease from a value of 138 ms at v' = 0 to 0.48 ms at v' = 8, and, for the X(2)Pi state, from 2.32 s at v = 1 to 0.59 s at v = 5. Vibrational and rotational transitions are expected to be relatively strong.
Resumo:
This paper presents the control strategies of nonlinear vehicle suspension using a magnetorheological (MR) damper. We used two different approaches for modeling and control of the mechanical and electrical parts of the suspension systems with the MR damper. First, we have formulated and resolved the control problem in order to design the linear feedback dumping force controller for a nonlinear suspension system. Then the values of the control dumping force functions were transformed into electrical control signals by the application of a fuzzy logic control method. The numerical simulations were provided in order to show the effectiveness of this method for the semi-active control of the quarter-car suspension.
Resumo:
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
Resumo:
A pitaya é uma cactácea de sub-bosque, originária de florestas tropicais do México e das Américas Central e do Sul, pouco estudada no Brasil, principalmente quanto à sua resposta à intensidade luminosa e adubação. Nesse sentido, realizou-se um experimento objetivando avaliar crescimento e desenvolvimento inicial da pitaya em função da intensidade luminosa e adubação orgânica. O delineamento experimental adotado foi em blocos casualizados, com tratamentos distribuídos em esquema fatorial 5 x 3, referentes, respectivamente, aos níveis de adubação orgânica (0; 5; 10; 20 e 30 L de esterco bovino cova-1) e aos percentuais de luz (0; 50 e 75% de sombreamento), com quatro repetições. Foram avaliados semanalmente diâmetro do cladódio (mm), altura de estacas (cm) e comprimento do ramo secundário (cm); ao final do experimento, massa fresca da parte aérea e massas secas de raiz e parte aérea (g), sendo que para as variáveis mensuradas, semanalmente, foram calculados os respectivos incrementos percentuais semanais. Segundo os resultados do presente trabalho, no cultivo da pitaya, é necessário o uso de cobertura contra a incidência direta dos raios solares, onde as estruturas com 50% ou 75% de luminosidade podem ser usadas. O fornecimento de 20 L cova-1 de esterco bovino pode ser adotado como quantitativo no preparo de covas de pitaya, nas condições de clima e solo de Bom Jesus-PI.
Resumo:
Sharp transitions are perhaps absent in QCD, so that one looks for physical quantities which may reflect the phase change. One such quantity is the sound velocity which was shown in lattice theory to become zero at the transition point for pure glue. We show that even in a simple bag model the sound velocity goes to zero at temperature T = T(v) not-equal 0 and that the numerical value of this T(v) depends on the nature of the meson. The average thermal energy of mesons goes linearly with T near T(v), with much smaller slope for the pion. The T(v) - s can be connected with the Boltzmann temperatures obtained from transverse momentum spectrum of these mesons in heavy-ion collision at mid-rapidity. It would be interesting to check the presence of different T(v) - s in present day finite T lattice theory.
Resumo:
This work deals with the synthesis, spectroscopic and structural investigation of pyrazolyl complexes of the type trans-[M(NCS)(2)(HPz)(4)] {M=Co (1), Ni (2); HPz=pyrazole}. Single crystal X-ray studies on 1 and 2 reveal the formation of similar supramolecular arrangements derived from self-assembly of monomers linked together through intermolecular N-H center dot center dot center dot SCN hydrogen bonds, C-H center dot center dot center dot pi interactions and pi-pi stacking. (c) 2005 Elsevier B.V. All rights reserved.
Resumo:
Two binuclear cyclometallated compounds [Pd(C-2,N-dmba)(mu-N-3)](2) (1) and [Pd-2(C-2,N-dmba)(2)(mu-N-3)(mu-Cl)] (2) (dmba = N,N-dimethylbenzylarnine) have been synthesized and characterized by elemental 3 analysis, IR and NMR spectroscopies and single crystal X-ray diffraction crystallography. The ability of CH3 groups to form C(sp(3))-H...pi hydrogen bonds with phenyl rings is responsible for the molecular self-assembly within the crystals of 1 and 2. Compound 1 crystallizes as one-dimensional supramolecular chains whereas the crystal packing of 2 consists of a herringbone of sandwiches composed by two inversely related [Pd-2(C-2,N-dmba)(2)(mu-N-3)(mu-Cl)] molecules. (c) 2007 Elsevier B.V. All rights reserved.
Resumo:
Robotic vehicle navigation in unstructured and uncertain environments is still a challenge. This paper presents the implementation of a multivalued neurofuzzy controller for autonomous ground vehicle (AGVs) in indoor environments. The control system consists of a hierarchy of mobile robot using multivalued adaptive neuro-fuzzy inference system behaviors.
Resumo:
The papers shows, through theoretical studies and simulations, that using the description of the plant by Takagi-Sugeno (T-S), it is possible to design a nonlinear controller to control the position of the leg of a paraplegic patient. The control system was designed to change the angle of the joint knee of 60 degrees. This is the first study that describes the application of Takagi-Sugeno (T-S) models in this kind of problem.