5,523 research outputs found
The ground state properties of the spin-1/2 transverse Ising chain with periodically varying bonds and fields
Using continued fractions we study the ground state properties of the
spin-1/2 Ising chain in a transverse field with periodically varying
interaction strengths and external fields. We consider in detail the chain
having the period of modulation of interactions equals 2 and compare the
results obtained with those corresponding to the spin-1/2 isotropic XY chain in
a transverse field. In contrast to the behaviour of the transverse XY chain,
the transverse Ising chain does not exhibit a step-like magnetization vs. field
dependence caused by the alternation of bonds, its susceptibility exhibits a
logarithmic singularity at the field determined by interaction strengths, and
it is stable with respect to spin-Peierls dimerization.Comment: 11 pages, latex, 4 figure
Teca (Tectona grandis L. f.): principais perguntas do futuro empreendedor florestal.
Introdução; Características da espécie; demandas ambientais; Produção de mudas; Plantio definitivo; Tratos culturais; Manejo florestal; Produção e economia; Conceitos florestaisbitstream/CPAF-AC/13198/1/doc97.pdfA bt. possui um exemp. na Produção Científica da Ud
Privacy-Preserving Outsourcing of Large-Scale Nonlinear Programming to the Cloud
The increasing massive data generated by various sources has given birth to
big data analytics. Solving large-scale nonlinear programming problems (NLPs)
is one important big data analytics task that has applications in many domains
such as transport and logistics. However, NLPs are usually too computationally
expensive for resource-constrained users. Fortunately, cloud computing provides
an alternative and economical service for resource-constrained users to
outsource their computation tasks to the cloud. However, one major concern with
outsourcing NLPs is the leakage of user's private information contained in NLP
formulations and results. Although much work has been done on
privacy-preserving outsourcing of computation tasks, little attention has been
paid to NLPs. In this paper, we for the first time investigate secure
outsourcing of general large-scale NLPs with nonlinear constraints. A secure
and efficient transformation scheme at the user side is proposed to protect
user's private information; at the cloud side, generalized reduced gradient
method is applied to effectively solve the transformed large-scale NLPs. The
proposed protocol is implemented on a cloud computing testbed. Experimental
evaluations demonstrate that significant time can be saved for users and the
proposed mechanism has the potential for practical use.Comment: Ang Li and Wei Du equally contributed to this work. This work was
done when Wei Du was at the University of Arkansas. 2018 EAI International
Conference on Security and Privacy in Communication Networks (SecureComm
Analytical results for a Bessel function times Legendre polynomials class integrals
When treating problems of vector diffraction in electromagnetic theory, the
evaluation of the integral involving Bessel and associated Legendre functions
is necessary. Here we present the analytical result for this integral that will
make unnecessary numerical quadrature techniques or localized approximations.
The solution is presented using the properties of the Bessel and associated
Legendre functions.Comment: 4 page
Effects of mating status on the oviposition behavior of Cleruchoides noackae (Hymenoptera: Mymaridae) in eggs of Thaumastocoris peregrinus (Hemiptera: Thaumastocoridae).
Uso de inseticidas alternativos no controle de pragas agrícolas.
Vantagens e desvantagens dos inseticidas naturais; Precauções durante a manipulação; Extratos vegetais: métodos artesanais de extração dos princípios ativos; Receitas para obtenção de inseticidas naturais de origem vegetal; Outros inseticidas ou métodos alternativos de controle.bitstream/CPATSA/33455/1/SDC191.pd
Manejo e controle da Cochonilha Ortézia (Orthezia praelonga), em plantios irrigados de acerola, no Submédio São Francisco.
O cultivo da acerola é uma importante alternativa econômica para a Região Nordeste do Brasil. No Submédio São Francisco, há cerca de mil hectares cultivados e a expansão do cultivo deve-se, basicamente, ao apreciado sabor da fruta e ao alto teor de ácido ascórbico (vitamina C), que, em algumas variedades, alcança até 5.000 miligramas por 100 gramas de polpa.bitstream/CPATSA/37176/1/CTE83.pd
Neuromorphometric characterization with shape functionals
This work presents a procedure to extract morphological information from
neuronal cells based on the variation of shape functionals as the cell geometry
undergoes a dilation through a wide interval of spatial scales. The targeted
shapes are alpha and beta cat retinal ganglion cells, which are characterized
by different ranges of dendritic field diameter. Image functionals are expected
to act as descriptors of the shape, gathering relevant geometric and
topological features of the complex cell form. We present a comparative study
of classification performance of additive shape descriptors, namely, Minkowski
functionals, and the nonadditive multiscale fractal. We found that the proposed
measures perform efficiently the task of identifying the two main classes alpha
and beta based solely on scale invariant information, while also providing
intraclass morphological assessment
Levantamento de Diaphorina citri (Hemiptera: psylidae), vetor do Huanglongbing (HLB), em três regiões produtoras de citros no estado da Bahia.
O psilídeo Diaphorina citri, Kuwayama, inseto-vetor da bactéria Candidatus Liberibacter causadora da devastadora doença dos citros: a Huanglongbing ? HLB - (ex-greening), ocorre praticamente em todas regiões produtoras de citros do país. A Bahia é considerada área livre desta doença. A transmissão do HLB ocorre por meio de enxertia com material contaminado ou por inoculação da bactéria no floema da planta pelo inseto vetor.PDF. 153_11
Development and emergence of Cleruchoides noackae (Hymenoptera:Mymaridae) in Thaumastocoris peregrinus (Hemiptera: Thaumastocoridae) eggs at different temperatures.
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