9,991 research outputs found

    Pretty good state transfer in qubit chains-The Heisenberg Hamiltonian

    Get PDF
    Pretty good state transfer in networks of qubits occurs when a continuous-time quantum walk allows the transmission of a qubit state from one node of the network to another, with fidelity arbitrarily close to 1. We prove that in a Heisenberg chain with n qubits, there is pretty good state transfer between the nodes at the jth and (n − j + 1)th positions if n is a power of 2. Moreover, this condition is also necessary for j = 1. We obtain this result by applying a theorem due to Kronecker about Diophantine approximations, together with techniques from algebraic graph theory

    Integraçao reduzida para problemas advectivos-difusivos escalares discretizados pela formulaçao Supg com operador de captura de descontinuidade

    Get PDF
    Este trabalho apresenta una técnica de controle das oscilaçoes esgúrias que podein surgir quando as integrais provenientes da discretizaçao de problemas escalares advectivos-difusivos em regime permanente pela formulaçao SUPG com operador de captura de descontinuidades, sao avaliadas utilizamdo-se um ponto de quadratura de Gauss. Os termos de correçao saoo obtidos a partir do princípio variacional de Hu-Washizu. Diversos exeinplos numéricos sao apresentados de forma a validar a técnica proposta. REDUCED INTEGRATION FOR STEADY ADVECTIVE-DIFFUSIVE PROBLEMS DISCRETIZED BY THE SUPG FORMULATION WITH DISCONTINUITY-CAPTURING SUMMARY This worlk presents a technique to control thee spurious oscillations that may appear when the integrals arising from the discretization of scalar steady-state advective-diffusive problems by the SUPG formulation with discontinuity-capturing are evaluated usiilg one-point Gaussian quadrature. Tlie correction terms are clerived froin a Hu-Wasl-iizu variational formulation. Severa1 numerical esamples a.re slzown, validating the proposed technique.Peer Reviewe

    Bioindicators as a tool for monitoring and control biofilm reactors : a simplified approach

    Get PDF
    The control of wastewater treatment plants requires an extensive monitoring programme based on physicochemical costly routine analysis. Microbial populations are well known indicators of operational conditions in biological reactors. This research was carried out by the CENTA and the University of Minho in the scope of the Erasmus programme. The aim of the work was the development of a simplified approach, based on biological indicators, for monitoring small biofilm wastewater treatment processes. In that regard, protozoa and metazoan were monitored at CENTA experimental plants - namely a trickling filter and a rotating biological contactor -, and correlated with influent wastewater and effluent composition. The relationship between wastewater performance and the microbiological composition of the biofilm was identified and assessed. Results indicate that a methodology based on the bioindicators provides useful data for process monitoring and control of small wastewater treatment plants, thus diminishing the associated costs of routine analysis and providing information when such analysis aren’t easily available

    Aspectos climáticos da região de Prado - BA.

    Get PDF
    Avaliação das chuvas em Prado - Bahia. Identificação dos períodos e dos anos de maiores oferta e escassez hídricas da área de estudo.bitstream/CNPS/11566/1/comtec13_2003_prado.pd

    Frustration-induced quantum phase transitions in a quasi-one-dimensional ferrimagnet: Hard-core boson map and the Ton ks-Girardeau limit

    Full text link
    We provide evidence of a superfluid-insulator transition (SIT) of magnons in a quasi-one-dimensional quantum ferrimagnet with {\it isotropic} competing antiferromagnetic spin interactions. This SIT occurs between two distinct ferrimagnetic phases due to the frustration-induced closing of the gap to a magnon excitation. It thus causes a coherent superposition of singlet and triplet states at lattice unit cells and a power-law decay on the staggered spin correlation function along the transverse direction to the spontaneous magnetization. A hard-core boson map suggests that asymptotically close to the SIT the magnons attain the Tonks-Girardeau limit. The quantized nature of the condensed singlets is observed before a first-order transition to a singlet magnetic spiral phase accompanied by critical antiferromagnetic ordering. In the limit of strong frustration, the system undergoes a decoupling transition to an isolated gapped two-leg ladder and a critical single linear chain

    Expressão de genes ligados à maciez da carne em bovinos da raça Nelore.

    Get PDF
    Dentre as características da carne, a maciez é a mais desejada pelo consumidor. Bovinos de origem Bos taurus indicus são conhecidos por produzirem carne de menor maciez quando comparado às raças de origem taurina. O objetivo do estudo foi avaliar a expressão dos genes codificadores de proteínas da família ?heat shock? (CRYAB, HSPB1 e DNAJA1) em bovinos da raça Nelore (Bos taurus indicus). A expressão do gene CRYAB foi associada à maciez aos sete (P=0,003) e 14 dias (P=0,01) de maturação, e do gene HSPB1 associado à força de cisalhamento 24 horas (P=0,04) após abate e aos 7 (P=0,003) e 14 dias (P=003) de maturação. Baseado nos resultados, é possível sugerir que os genes CRYAB e HSBP1 podem ser potenciais marcadores de maciez da carne em bovinos da raça Nelore

    Teste de paternidade na raça Nelore por meio de exame do DNA.

    Get PDF
    Foi estimado as freqüências gênicas para os marcadores RFLP Kapa-caseina e hormônio do crescimento e os microssatélites
    • …
    corecore