400 research outputs found
Integration of Host Plant Resistance and Insecticides in the Control of \u3ci\u3eNephotettix virescens\u3c/i\u3e (Homoptera: Cicadelli-dae), a Vector of Rice Tungro Virus
Combined effects of levels of vector resistance and insecticide application in control of rice tungro virus (RTV) were determined in three field tests. Cultivar “IR28,” with high levels of resistance to the vector, Nephotettix virescens (Distant), had low RTV infection in all treatments including the untreated check. In moderately resistant “IR36,” RTV decreased with an increase in level of insecticide but did not decrease to a level equaling the untreated “IR28.” The N. virescens-susceptible cultivar “IR22” had extremely high levels of RTV infection at all insecticide levels. Economic analysis indicated that gross profit and net gain were highest in the N. virescens-resistant “IR28,” intermediate in moderately resistant “IR36,” and lowest in susceptible “IR22.
On the dynamics and control of continuous fluidized bed layering granulation with screen-mill-cycle
On the arithmetic sums of Cantor sets
Let C_\la and C_\ga be two affine Cantor sets in with
similarity dimensions d_\la and d_\ga, respectively. We define an analog of
the Bandt-Graf condition for self-similar systems and use it to give necessary
and sufficient conditions for having \Ha^{d_\la+d_\ga}(C_\la + C_\ga)>0 where
C_\la + C_\ga denotes the arithmetic sum of the sets. We use this result to
analyze the orthogonal projection properties of sets of the form C_\la \times
C_\ga. We prove that for Lebesgue almost all directions for which the
projection is not one-to-one, the projection has zero (d_\la +
d_\ga)-dimensional Hausdorff measure. We demonstrate the results on the case
when C_\la and C_\ga are the middle-(1-2\la) and middle-(1-2\ga) sets
A test for a conjecture on the nature of attractors for smooth dynamical systems
Dynamics arising persistently in smooth dynamical systems ranges from regular
dynamics (periodic, quasiperiodic) to strongly chaotic dynamics (Anosov,
uniformly hyperbolic, nonuniformly hyperbolic modelled by Young towers). The
latter include many classical examples such as Lorenz and H\'enon-like
attractors and enjoy strong statistical properties.
It is natural to conjecture (or at least hope) that most dynamical systems
fall into these two extreme situations. We describe a numerical test for such a
conjecture/hope and apply this to the logistic map where the conjecture holds
by a theorem of Lyubich, and to the Lorenz-96 system in 40 dimensions where
there is no rigorous theory. The numerical outcome is almost identical for both
(except for the amount of data required) and provides evidence for the validity
of the conjecture.Comment: Accepted version. Minor modifications from previous versio
Simultaneous Continuation of Infinitely Many Sinks Near a Quadratic Homoclinic Tangency
We prove that the diffeomorphisms on surfaces, exhibiting infinitely
many sinksnear the generic unfolding of a quadratic homoclinic tangency of a
dissipative saddle, can be perturbed along an infinite dimensional manifold of
diffeomorphisms such that infinitely many sinks persist simultaneously.
On the other hand, if they are perturbed along one-parameter families that
unfold generically the quadratic tangencies, then at most a finite number of
those sinks have continuation
Lyapunov-based online parameter estimation in continuous fluidized bed spray agglomeration processes
- …