Ocorrência de fungos em sementes de cevada produzidas em sistema irrigado por pivô central no cerrado brasileiro.

O objetivo desse trabalho foi determinar a ocorrência de fungos em sementes de cevada produzidas em sistema irrigado por pivô central na região do Distrito Federal e entorno.bitstream/item/38772/1/BP200418.pd

Improving Provenance Data Interaction for Visual Storytelling in Medical Imaging Data Exploration

Effective collaborative work in diagnostic medical imaging is not trivial due to the large amounts of complex data involved,a (non-linear) workflow involving experts in different domains, and a lack of versatility in the current tools employed inhealthcare. In this paper, we aim to introduce how the integration of visual storytelling techniques together with provenancedata in the analytic systems used in medicine can compensate for these issues, by enhancing communication of results andreproducibility of findings through diagnostic provenance data. To this end, we illustrate how we can improve the interactionwith provenance data displayed in a graph in order to facilitate authoring and the creation process of visual data storie

Damage detections in nonlinear vibrating thermally loaded plates

In this work, geometrically nonlinear vibrations of fully clamped rectangular plates subjected to thermal changesare used to study the sensitivity of some vibration response parameters to the presence of damage and elevated temperature. The geometrically nonlinear version of the Mindlin plate theory is used to model the plate behaviour.Damage is represented as a stiffness reduction in a small area of the plate. The plates are subjected to harmonicloading leading to large amplitude vibrations and temperature changes. The plate vibration response is obtained by a pseudo-load mode superposition method. The main results are focussed on establishing the influence of damage on the vibration response of the heated and the unheated plates and the change in the time-history diagrams and the Poincaré maps caused by damage and elevated temperature. The damage criterion formulated earlier for nonheated plates, based on analyzing the points in the Poincaré sections of the damaged and healthy plate, is modified and tested for the case of plates additionally subjected to elevated temperatures. The importance of taking into account the actual temperature in the process of damage detection is shown

N-1 modal interactions of a three-degree-of-freedom system with cubic elastic nonlinearities

In this paper the (Formula presented.) nonlinear modal interactions that occur in a nonlinear three-degree-of-freedom lumped mass system, where (Formula presented.), are considered. The nonlinearity comes from springs with weakly nonlinear cubic terms. Here, the case where all the natural frequencies of the underlying linear system are close (i.e. (Formula presented.)) is considered. However, due to the symmetries of the system under consideration, only (Formula presented.) modes interact. Depending on the sign and magnitude of the nonlinear stiffness parameters, the subsequent responses can be classified using backbone curves that represent the resonances of the underlying undamped, unforced system. These backbone curves, which we estimate analytically, are then related to the forced response of the system around resonance in the frequency domain. The forced responses are computed using the continuation software AUTO-07p. A comparison of the results gives insights into the multi-modal interactions and shows how the frequency response of the system is related to those branches of the backbone curves that represent such interactions

Identification by means of a genetic algorithm of nonlinear damping and stiffness of continuous structures subjected to large-amplitude vibrations. Part II: one-to-one internal resonances

A procedure is presented to identify the nonlinear damping and stiffness parameters of harmonically forced continuous systems showing nonlinear vibrations with a one-to-one internal resonance. The identification is obtained by using a two-degree-of-freedom (2DOF) model. Cubic nonlinear damping is introduced in the 2DOF model in addition to the classical viscous one. Different damping coefficients are considered within or outside the internal resonance frequency range. The parameter estimation relies on the harmonic balance method. It is shown that a three-harmonic expansion is needed to obtain a converged solution, although often only the first harmonic, without mean component, is experimentally measured with accuracy. The proposed novel cascade procedure consists in (i) a single-term harmonic balance parameter estimation used as initiation of (ii) a minimization of the distance between data and a three-term harmonic balance model by means of a genetic algorithm. These procedures are validated by parameter identification on synthetic (numerically generated) and experimentally measured frequency–responses. The nonlinear damping model is validated by comparison with level-adjusted linear damping model estimated at each level of harmonic force, demonstrating its ability to account for the evolution of damping with the vibration amplitude for different branches of solutions