Manejo de plantas daninhas na produção de arroz orgânico.

bitstream/item/78976/1/documento-304.pd

Diferenças entre espécies de Ervilhaca (Vicia sativa e Vicia villosa) quanto à sensibilidade aos herbicidas utilizados para seu controle em trigo.

bitstream/item/36298/1/comunicado-244.pd

Tolerância de Capim-arroz (Echinochloa crus-galli spp.) ao Herbicida Imazetapir + Imazapic em arrozais da região Sudeste do RS.

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Controle químico de um biótipo de capim-arroz com provável resistência aos herbicidas inibidores de ALS - recomendação preliminar.

bitstream/item/46796/1/Circular-96.pd

Orientações para o uso correto de herbicidas no arroz BRS Sinuelo CL.

bitstream/item/32586/1/Orientacoes.para.uso.correto.de.herbicidas.no.arroz.BRS.Sinuelo.pdfResponsáveis técnicos: Giovani Theisen, André Andres (CPACT)

Épocas de controle de angiquinho e prejuízos em arroz irrigado cv. BRS QUERÊNCIA.

bitstream/item/30503/1/boletim-93.pd

On the properties of compacton-anticompacton collisions

We study the properties of compacton-anticompacton collision processes. We compare and con- trast results for the case of compacton-anticompacton solutions of the K(l, p) Rosenau-Hyman (RH) equation for l = p = 2, with compacton-anticompacton solutions of the L(l,p) Cooper-Shepard- Sodano (CSS) equation for p = 1 and l = 3. This study is performed using a Pad\'e discretization of the RH and CSS equations. We find a significant difference in the behavior of compacton- anticompacton scattering. For the CSS equation, the scattering can be interpreted as "annihila- tion" as the wake left behind dissolves over time. In the RH equation, the numerical evidence is that multiple shocks form after the collision which eventually lead to "blowup" of the resulting waveform.Comment: 8 pages, 7 figure

Stability and dynamical properties of Rosenau-Hyman compactons using Pade approximants

We present a systematic approach for calculating higher-order derivatives of smooth functions on a uniform grid using Pad\'e approximants. We illustrate our findings by deriving higher-order approximations using traditional second-order finite-differences formulas as our starting point. We employ these schemes to study the stability and dynamical properties of K(2,2) Rosenau-Hyman (RH) compactons including the collision of two compactons and resultant shock formation. Our approach uses a differencing scheme involving only nearest and next-to-nearest neighbors on a uniform spatial grid. The partial differential equation for the compactons involves first, second and third partial derivatives in the spatial coordinate and we concentrate on four different fourth-order methods which differ in the possibility of increasing the degree of accuracy (or not) of one of the spatial derivatives to sixth order. A method designed to reduce roundoff errors was found to be the most accurate approximation in stability studies of single solitary waves, even though all derivates are accurate only to fourth order. Simulating compacton scattering requires the addition of fourth derivatives related to artificial viscosity. For those problems the different choices lead to different amounts of "spurious" radiation and we compare the virtues of the different choices.Comment: 12 figure