23 research outputs found
Remarks on symmetry analysis of Lane-Emden systems of dimensions one and two
Some recent results on Lie group analysis of the one and bi-dimensional Lane-Emden systems are revisited.Alguns resultados recentes sobre simetrias de Lie de sistemas de Lane-Emden uni e bidimensionais são revisitados.245254Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq
Replicate Periodic Windows in the Parameter Space of Driven Oscillators
In the bi-dimensional parameter space of driven oscillators, shrimp-shaped
periodic windows are immersed in chaotic regions. For two of these oscillators,
namely, Duffing and Josephson junction, we show that a weak harmonic
perturbation replicates these periodic windows giving rise to parameter regions
correspondent to periodic orbits. The new windows are composed of parameters
whose periodic orbits have periodicity and pattern similar to stable and
unstable periodic orbits already existent for the unperturbed oscillator. These
features indicate that the reported replicate periodic windows are associated
with chaos control of the considered oscillators
Composição de uma taxocenose de serpentes em uma área urbana na Mata Atlântica da Paraíba, Nordeste do Brasil
On The Lane-emden System In Dimension One
We carry out a complete group classification of the nonlinear Lane-Emden systems in dimension one. © 2012 Elsevier Inc. All rights reserved.218211076210766Bluman, G.W., Anco, S., (2002) Symmetry and Integration Methods for Differential Equations, , Springer New YorkBluman, G.W., Kumei, S., (1989) Symmetries and Differential Equations, 81. , Applied Mathematical Sciences Springer New YorkBokhari, A.H., Mahomed, F.M., Zaman, F.D., Symmetries and integrability of a fourth-order Euler-Bernoulli beam equation (2010) J. Math. Phys., 51, p. 053517Bozhkov, Y., Gilli Martins, A.C., Lie point symmetries of the Lane-Emden systems (2004) Journal of Mathematical Analysis and Applications, 294 (1), pp. 334-344. , DOI 10.1016/j.jmaa.2004.02.022, PII S0022247X04001532Bozhkov, Y., Freire, I.L., Symmetry analysis of the bidimensional Lane-Emden systems (2012) J. Math. Anal. Appl., 388, pp. 1279-1284. , 10.1016/j.jmaa.2011.11.024Bozhkov, Y., Freire, I.L., (2012) The Complete Group Classification of Lane-Emden Systems, , in preparationDai, Q., Tisdell, C., Nondegeneracy of positive solutions to homogeneous second-order differential systems and its applications (2009) Acta Math. Sci. Ser., 29, pp. 435-446Freire, I.L., Silva, P.L., Torrisi, M., Symmetry and Integrability of A Fourth-order Emden-Fowler Equation, , 2012 submitted for publicationIbragimov, N.H., (1985) Transformation Groups Applied to Mathematical Physics, , Translated from the Russian Mathematics and its Applications (Soviet Series) D. Reidel Publishing Co. DordrechtIbragimov, N.H., Integrating factors, adjoint equations and Lagrangians (2006) Journal of Mathematical Analysis and Applications, 318 (2), pp. 742-757. , DOI 10.1016/j.jmaa.2005.11.012, PII S0022247X05011546Ibragimov, N.H., A new conservation theorem (2007) J. Math. Anal. Appl., 333, pp. 311-328Muatjetjeja, B., Khalique, C.M., Lagrangian approach to a generalized coupled Lane-Emden system: Symmetries and first integrals (2010) Commun. Nonlinear Sci. Numer. Simulat., 15, pp. 1166-1171Muatjetjeja, B., Khalique, C.M., Noether partial Noether operators and first integrals for the coupled Lane-Emden system (2010) Math. Comput. Appl., 15, pp. 325-333Muatjetjeja, B., Khalique, C.M., First integrals for a generalized coupled Lane-Emden system (2011) Nonlinear Anal. Real World Appl., 12, pp. 1202-1212Olver, P.J., (1986) Applications of Lie Groups to Differential Equations, , Springer New Yor
Group Classification Of Semilinear Kohn-laplace Equations
We study the Lie point symmetries of semilinear Kohn-Laplace equations on the Heisenberg group H1 and obtain a complete group classification of these equations. © 2007 Elsevier Ltd. All rights reserved.68925522568American Mathematical Society, MathSciNet Search, Matches for: Heisenberg group, Number of Matches = 624, 15 January 2007Baaquie, B.E., Yim, K.K., Sigma model Lagrangian for the Heisenberg group (2005) Phys. Lett. B, 615, pp. 134-140Beals, R., Geometry and PDE on the Heisenberg group: A case study (2001) Contemp. Math., 285, pp. 21-27Biagini, S., Positive solutions for a semilinear equation on the Heisenberg group (1995) Boll. Unione. Mat. Ital. Sez. B (7), 9, pp. 883-900Birindelli, I., Capuzzo Dolcetta, I., Cutri, A., Indefinite semi-linear equations on the Heisenberg group: A priori bounds and existence (1995) Comm. Partial Differential Equations, 23, pp. 1123-1157Birindelli, I., Lanconelli, E., A negative answer to a one-dimensional symmetry problem in the Heisenberg group (2003) Calc. Var. Partial Differential Equations, 18, pp. 357-372Bluman, G.W., Simplifying the form of Lie groups admitted by a given differential equation (1990) J. Math. Anal. Appl., 145, pp. 52-62Bluman, G.W., Kumei, S., (1989) Symmetries and Differential Equations, , Springer, New YorkBozhkov, Y., Noether symmetries and critical exponents (2005) SIGMA Symmetry Integrability Geom. Methods Appl., 1. , 12. Paper 022, electronicBozhkov, Y., Divergence symmetries of semilinear polyharmonic equations involving critical nonlinearities (2006) J. Differential Equations, 225, pp. 666-684Y. Bozhkov, I.L. Freire, Divergence symmetries of critical Kohn-Laplace equations on Heisenberg groups, Quaderni Matematici, n. 571, Università di Trieste, 2006, Differ. Equ (Differ. Uravn) (2007) (in press)Y. Bozhkov, I.L. Freire, Conservation laws for critical semilinear Kohn-Laplace equations on the Heisenberg group, 2007, R. P. 04/07, February 2007, IMECC-UNICAMP (submitted for publication)Y. Bozhkov, I.L. Freire, Invariant solutions of Kohn-Laplace equations on the Heisenberg group, 2007 (in preparation)Folland, G.B., (1989) Annals of Mathematics Studies, 122. , Princeton University Press, Princeton, NJFolland, G.B., Stein, E.M., Estimates for the over(∂, ̄)b complex and analysis on the Heisenberg group (1974) Comm. Pure Appl. Math., 27, pp. 429-522Garofalo, N., Lanconelli, E., Zero-order perturbations of the subelliptic Laplacian on the Heisenberg group and their uniqueness properties (1990) Bull. Amer. Math. Soc. (N.S.), 23, pp. 501-512Garofalo, N., Lanconelli, E., Frequency functions on the Heisenberg group, the uncertainty principle and unique continuation (1990) Ann. Inst. Fourier (Grenoble), 40, pp. 313-356Garofalo, N., Lanconelli, E., Existence and nonexistence results for semilinear equations on the Heisenberg group (1992) Indiana Univ. Math. J., 41, pp. 71-98Hörmander, L., Hypoelliptic second order differential equations (1967) Acta Math., 119, pp. 147-171Howe, R., On the role of the Heisenberg group in harmonic analysis (1980) Bull. Amer. Math. Soc. (N.S.), 3, pp. 821-843Hueber, H., Müller, D., Asymptotics for some Green kernels on the Heisenberg group and the Martin boundary (1989) Math. Ann., 283, pp. 97-119Ibragimov, N.H., (1985) Transformation Groups Applied to Mathematical Physics, , D. Reidel Publishing Co., Dordrecht Translated from Russian Mathematics and its Applications (Soviet Series)Jerison, D.S., The Dirichlet problem for the Kohn Laplacian on the Heisenberg group. I (1981) J. Funct. Anal., 43, pp. 97-142Jerison, D.S., The Dirichlet problem for the Kohn Laplacian on the Heisenberg group. II (1981) J. Funct. Anal., 43, pp. 224-257Jerison, D.S., Lee, J.M., Intrinsic CR normal coordinates and the CR Yamabe problem (1989) J. Differential Geom., 29, pp. 303-343Jerison, D.S., Lee, J.M., Extremals for the Sobolev inequality on the Heisenberg group and the CR Yamabe problem (1988) J. Amer. Math. Soc., 1, pp. 1-13Olver, P.J., (1986) GTM, 107. , Springer, New YorkOvsiannikov, L.V., (1982) Group Analysis of Differential Equations, , Academic Press, New York, London Translated from RussianPohozaev, S.I., Veron, L., Nonexistence results of solutions of semilinear differential inequalities on the Heisenberg group (2000) Manuscripta Math., 102, pp. 85-99Svirshchevskii, S.R., Group classification of nonlinear polyharmonic equations and their invariant solutions (1993) Differ. Equ., 29, pp. 1538-1547. , Differ. Uravn. 29 (10), 1772-1781 (in Russian
A review on some results on local conservation laws for certain evolution equations
In this work we revisit some recent results on conservation laws for a class of fifth-order evolution equations up to fifth-order.Neste trabalho revisitamos alguns resultados recentes sobre leis de conservação de uma classe de equações evolutivas até quinta ordem.10911
O IMPACTO DOS TRIBUTOS NO PREÇO ABSOLUTO
O presente trabalho tem como objetivo mostrar a influência dos impostos na formação de preços de venda, a importância de um bom planejamento tributário, é possível concluir os impactos na formação do custo de aquisição, assim como na também formação do preço de absoluto deve ser estratégia a ser considera pelas empresas, já que praticamente pequenas alterações nos custos provocam, por vezes, grandes impactos no preço de venda e, por consequência, na capacidade competitiva de qualquer empresa
Alterações anatômicas em algodoeiro infectado pelo vírus da doença azul Anatomical alterations in blue disease infected cotton plant
A doença azul do algodoeiro está associada a um vírus ainda pouco conhecido em suas características morfológicas e moleculares, tanto quanto a sua patologia e epidemiologia. O tipo de transmissão circulativa pelo afídeo vetor Aphis gossypii Glover, associado a recentes relatos de estudos moleculares, sustentam ser o agente etiológico uma espécie membro da família Luteoviridae. No presente trabalho, estudos anatômicos comparativos em plantas sadias e infectadas foram realizados com a finalidade de conhecer aspectos estruturais da interação vírus-espécie hospedeira, com potencial aplicação na área de diagnose e melhoramento genético. Os estudos anatômicos foram realizados em folhas de plantas infectadas, com área foliar reduzida, nervuras cloróticas e margem foliar voltada para baixo. O encurtamento dos entrenós, que resultam em um agrupamento de folhas, flores e frutos, e conseqüente redução da altura da planta, do número e tamanho dos frutos, são expressões fenotípicas da planta de algodão infectada, a qual serviu para o presente estudo. Nas plantas infectadas com o agente da doença azul havia maior acúmulo de calose e de cristais de oxalato de cálcio, cloroplastos íntegros distribuídos na região periférica das células do mesofilo e aparente alteração química no interior das células do parênquima paliçádico. Inclusões nos vasos do floema e, ocasionalmente no xilema, também foram observadas. O acúmulo de calose e a presença de inclusões no floema podem indicar uma relação ou preferência do vírus por esse tecido.<br>Cotton blue disease is caused by a virus whose morphological and molecular characteristics is not well known and so demanding information its phytosanitary and epidemiological characteristics. Evidences of an aphid borne (Aphis gossypii Glover) circulative (persistent) type of transmission, associated with a recent molecular report, sustain for a virus species belonging to the Luteoviridae family. Aiming to understand virus-host pathogenesis as well as to contribute with diagnostic and breeding aspects of cotton blue disease, in the present work, structural studies were performed via anatomical comparative analysis of health and infected plant tissues. For the anatomical studies, leaves from infected cotton plants were chosen when showing typical symptoms, such as: stunting, reduced leaf area with chlorotic vein and edges curled downward; clustered leaves, flowers and fruits due to reduced stem internodes. The results revealed that infected tissues present an increase in callose accumulation and calcium oxalate crystals; integrity of chloroplasts, which were distributed on the peripheral mesophyll cells, revealed a chemical alteration in the interior of palisade parenchyma cells. Inclusions in phloem and occasionally also xylem vessels were observed. The callose accumulation and the presence of inclusions in the phloem vessels are indications of a preferential relationship of the virus to these tissues