222 research outputs found
Caracterização morfológica e agressividade de populações de Pratylenchus spp. do RS em cana-de-açúcar e manejo de fitonematoides na cultura pelo emprego de rizobactérias.
(Mestrado) - do Programa de Pós-Graduação em Agronomia - Agricultura e Ambiente, Universidade Federal de Santa Maria (UFSM - FW, RS), Orientadora: Stela Maris Kulczynski, Coorientador: Cesar Bauer Gomes, Juliane Ludwig
Conformal Antenna Array for Millimeter-Wave Communications: Performance Evaluation
In this paper, we study the influence of the radius of a cylindrical
supporting structure on radiation properties of a conformal millimeter-wave
antenna array. Bent antenna array structures on cylindrical surfaces may have
important applications in future mobile devices. Small radii may be needed if
the antenna is printed on the edges of mobile devices and in items which human
beings are wearing, such as wrist watches, bracelets and rings. The antenna
under study consists of four linear series-fed arrays of four patch elements
and is operating at 58.8 GHz with linear polarization. The antenna array is
fabricated on polytetrafluoroethylene substrate with thickness of 0.127 mm due
to its good plasticity properties and low losses. Results for both planar and
conformal antenna arrays show rather good agreement between simulation and
measurements. The results show that conformal antenna structures allow
achieving large angular coverage and may allow beam-steering implementations if
switches are used to select between different arrays around a cylindrical
supporting structure.Comment: Keywords: conformal antenna, millimeter-wave communications, patch
antenna array. 11 pages, 10 figures, 1 tabl
Analycity and smoothing effect for the coupled system of equations of Korteweg - de Vries type with a single point singularity
We study that a solution of the initial value problem associated for the
coupled system of equations of Korteweg - de Vries type which appears as a
model to describe the strong interaction of weakly nonlinear long waves, has
analyticity in time and smoothing effect up to real analyticity if the initial
data only has a single point singularity at $x=0.
In vitro screening of interspecific hybrids (Malus spp.) for resistance to apple proliferation
A breeding programme was set up six years ago in Trentino as part of the Project “Scopazzi del Melo - Apple Proliferation” (SMAP) in order to obtain AP resistant apple rootstocks.Twenty-six hybrids generated from the crossings (Malus sieboldii, second generation, x Malus domestica) were micropropagated and studied in standardised conditions. An in vitro screening system for AP resistance previously set for the parents of the crosses was adopted and modified. Specific symptoms of the disease, as well as height and basal proliferation of the shoot and size of the leaves, were recorded in vitro at 3 months post-inoculation. At the same time, phytoplasma concentration was determined in the whole shoot by quantitative RT-PCR. An in vitro disease index taking into account all the above-mentioned parameters was developed.Each healthy genotype was graft-inoculated in triplicate with two different phytoplasma strains after plant rooting and acclimatisation. Phenotype and phytoplasma titre were evaluated in the roots the year after infection.Preliminary results indicated that the resistance trait segregates in the progenies. The resistant genotypes had lower phytoplasma concentrations than the susceptible controls, did not show AP-specific symptoms and their growth was not affected by infection. By comparing the resistant behaviour of the same genotypes, the in vitro screening allows for a quick selection of genotypes that are worth evaluating in the field for agronomic traits.Keywords: Apple Proliferation, Malus sieboldii, resistance screening, quantitative real-time PCR, disease inde
Holographic quark matter with colour superconductivity and a stiff equation of state for compact stars
We present a holographic model of QCD with a first order chiral restoration
phase transition with chemical potential, mu. The first order behaviour follows
from allowing a discontinuity in the dual description as the quarks are
integrated out below their constituent mass. The model predicts a deconfined
yet massive quark phase at intermediate densities (350 MeV< mu <500 MeV), above
the nuclear density phase, which has a very stiff equation of state and a speed
of sound close to one. We also include a holographic description of a colour
superconducting condensate in the chirally restored vacuum and study the
resulting equation of state. They provides a well behaved first order
transition from the deconfined massive quark phase at very high density (mu>500
MeV). We solve the Tolman-Oppenheimer-Volkoff equations with the resulting
equations of state and find stable hybrid stars with quark cores. We compute
the tidal deformability for these hybrid stars and show they are consistent
with LIGO/Virgo data on a neutron star collision. Our holographic model shows
that quark matter could be present at the core of such compact stars.Comment: 17 pages, 14 figure
Three-dimensional printed ABS plastic peanut-lens with integrated ball grid array module for high-data-rate communications in F-band
A ball grid array (BGA) module integrated within a three-dimensional printed peanut-shaped lens is proposed for high-data-rate wireless communications in the F-band (116–140 GHz) between a video camera and a TV or a laptop. The module implements a 1?×?2 array antenna which radiates a wide beam in the horizontal plane (H-plane) and a narrower beam in the vertical plane (E-plane). The dielectric lens, fabricated in ABS-M30 plastic, is a shaped lens designed to achieve a fan-beam radiation pattern further narrowing the vertical plane and widening the horizontal plane of the BGA module. The realised gain of the full antenna system is required to exceed 5?dBi within a 120° angular interval in the horizontal plane and a 20° angular interval in the vertical plane. Measurements show a reflection coefficient below ?9?dB from 116 to 140?GHz and a maximum realised gain of 8.5?dBi at 130?GHz demonstrating feasibility of the cost-effective proposed design for a high-data-rate communications.info:eu-repo/semantics/acceptedVersio
- …