A note on learning chaotic sunspot equilibrium

In this paper we prove convergence to chaotic sunspot equilibrium through two learning rules used in the bounded rationality literature. The rst one shows the convergence of the actual dynamics generated by simple adaptive learning rules to a probability distribution that is close to the stationary measure of the sunspot equilibrium; since this stationary measure is absolutely continuous it results in a robust convergence to the stochastic equilibrium. The second one is based on the E-stability criterion for testing stability of rational expectations equilibrium, we show that the conditional probability distribution de ned by the sunspot equilibrium is expectational stable under a reasonable updating rule of this parameter. We also report some numerical simulations of the processes proposed.

Contractual solutions to the holdup problem: a survey

In this survey, we presented the general idea and main results from what we understand that are the most important contributions to contractual solutions to the holdup problem literature. The aim of this paper is to push the previous analysis, uniform the notation and provide a snapshot on the most recent literature, as well as bring topics for future inquires on this issue.

DEGENERATE HOPF BIFURCATIONS IN CHUA'S SYSTEM

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

DYNAMICS AT INFINITY of A CUBIC CHUA'S SYSTEM

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

PERIODIC PERTURBATION of QUADRATIC SYSTEMS WITH TWO INFINITE HETEROCLINIC CYCLES

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Time-periodic perturbation of a Lienard equation with an unbounded homoclinic loop

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Migration of diethylhexyl phthalate from PVC bags into intravenous cyclosporine solutions

The migration of diethylhexyl phthalate (DEHP) from PVC bags into LVPS (0.9% NaCl) and LVPS with cyclosporine at concentrations of 2.5 and 0.5 mg/ml was studied. PVC bags were placed in contact with these solutions and stored at 25 1 degrees C. They were taken for analysis each 30 min during 6 h and after this period at each 1 h until 12 h of contact. Water was used as reference, and exposed and analyzed under the same conditions. After contact, the solutions were submitted to extraction with hexane and analyzed by GC-FID. The results showed that DEHP did not migrate into water and LVPS during all the time. Also, no measurable amount of DEHP was detected during the first 3 h of contact between the PVC bag and the diluted cyclosporine solution. However, the amount of released DEHP reached a detectable level after 4 It of contact, increased until 6 h, stabilized, and increased again after 9-10 h. The 12 h of contact showed the highest DEHP levels for both cyclosporine concentrations. The DEHP migrated was 0.02-0.08% of that present in the bag. (c) 2005 Elsevier B.V. All rights reserved.

Raman and photoluminescence of Er3+-doped SnO2 obtained via the sol-gel technique from solutions with distinct pH

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Bounded solutions of fermions in the background of mixed vector-scalar inversely linear potentials

The problem of a fermion subject to a general mixing of vector and scalar potentials in a two-dimensional world is mapped into a Sturm-Liouville problem. Isolated bounded solutions are also searched. For the specific case of an inversely linear potential, which gives rise to an effective Kratzer potential in the Sturm-Liouville problem, exact bounded solutions are found in closed form. The case of a pure scalar potential with their isolated zero-energy solutions, already analyzed in a previous work, is obtained as a particular case. The behavior of the upper and lower components of the Dirac spinor is discussed in detail and some unusual results are revealed. The nonrelativistic limit of our results adds a new support to the conclusion that even-parity solutions to the nonrelativistic one-dimensional hydrogen atom do not exist. (c) 2004 Elsevier B.V. All rights reserved.

General solutions for some classes of interacting two field kinks

In this work we present some classes of models whose the corresponding two coupled first-order nonlinear equations can be put into a linear form, and consequently be solved completely. In these cases the so-called trial orbit method is completely unnecessary. We recall that some physically important models as, for instance, the problem of tiling a plane with a network of defects and polymer properties are in this class of models. (c) 2005 Elsevier B.V. All rights reserved.

Bounded solutions of fermions in the background of mixed vector-scalar Poeschl-Teller-like potentials

The problem of a fermion subject to a convenient mixing of vector and scalar potentials in a two-dimensional space-time is mapped into a Sturm-Liouville problem. For a specific case which gives rise to an exactly solvable effective modified Poschl-Teller potential in the Sturm-Liouville problem, bound-state solutions are found. The behaviour of the upper and lower components of the Dirac spinor is discussed in detail and some unusual results are revealed. The Dirac delta potential as a limit of the modified Poschl-Teller potential is also discussed. The problem is also shown to be mapped into that of massless fermions subject to classical topological scalar and pseudoscalar potentials. Copyright (C) EPLA, 2007.

Two field BPS solutions for generalized Lorentz breaking models

In this work we present nonlinear models in two-dimensional space-time of two interacting scalar fields in the Lorentz and CPT violating scenarios. We discuss the soliton solutions for these models as well as the question of stability for them. This is done by generalizing a model recently published by Barreto and collaborators and also by getting new solutions for the model introduced by them.