Estimativa de custos de produção de arroz na região do cone Sul de Rondônia - safra 2000/01.

Este trabalho foi efetuado com o objetivo de apresentar uma estimativa dos custos: fixo e variável, e total da cultura em plantio convencional.bitstream/item/42625/1/cot185-arroz.pd

Estimativa de custos de produção de soja, em plantio direto e convencional, para a região do cerrado de Rondônia - safra 2000 / 01.

Tem-se como objetivo apresentar estimativa dos custos: fixo, variável e total da cultura da soja em plantio convencional no município de Vilhena, RO.bitstream/item/42615/1/cot184-soja.pd

Universal quantum signature of mixed dynamics in antidot lattices

We investigate phase coherent ballistic transport through antidot lattices in the generic case where the classical phase space has both regular and chaotic components. It is shown that the conductivity fluctuations have a non-Gaussian distribution, and that their moments have a power-law dependence on a semiclassical parameter, with fractional exponents. These exponents are obtained from bifurcating periodic orbits in the semiclassical approximation. They are universal in situations where sufficiently long orbits contribute.Comment: 7 page

Estimativa de custos de produção de milho safrinha, em plantio direto na palha, para a região do cerrado de Rondônia, safra 1998.

A expectativa de bons preços para o milho devido o baixo estoque internacional, associados à criação do corredor de exportação BR 364 - hidrovia Madeira-Amazonas tem gerado novas perspectivas para cultura no estado de Rondônia. Além disso, a cultura se ajusta perfeitamente a um programa de sucessão à cultura da soja, uma necessidade agronômica. Este trabalho foi efetuado com o objetivo de apresentar uma primeira estimativa dos custos: fixo, variável e total da cultura em plantio direto

Numerical and experimental development of cupronickel filler brazed joints for divertor and first wall components in DEMO fusion reactor

The brazeability of a cupronickel commercial alloy (Cu10Ni) was evaluated for its use as a filler alloy for high- temperature joining of tungsten to the reduced activation ferritic/martensitic steel EUROFER 97 (W-E) and between tungsten base materials (W-W) for its application at the first wall and divertor of future fusion reactors. In addition, given the importance of the residual stresses in these heterogenous joints, a study of the brazing conditions and the impact of the selected filler has been conducted using numerical software to understand its impact on the quality of the joint. Two thermal cycles were evaluated (1165 $^◦$C and 1190$^◦$C) and selected based on the thermal characterization of the filler alloy. The microstructural examination revealed that, in W-E joints, nickel acts as an activator element, reacting and forming interfacial layers at the EUROFER 97 - Cu10Ni interface. In the case of the W-W joints, a lower level of diffusion phenomenon and metallurgical interaction between Cu10Ni and base materials were observed. The hardness profile indicated that the hardening process of EUROFER 97 was associated with the formation of untempered martensite. On the other hand, tungsten kept the received hardness. The me- chanical characterization by shear test reported similar values between both types of joints carried out at 1190$^◦$C but different when the temperature was increased (1165 $^°$C), associated with the brittle character of tungsten and its lower metallurgical interaction. The numerical analysis of the brazing process carried out with ANSYS software shows that residual stresses are accumulated mainly at the interfaces. The information provided by the simulation shows, for a 50 μm filler thickness, the importance of mitigating the residual stress by selecting a filler with an intermediate Coefficient of Thermal Expansion (CTE) that alleviates mechanical stresses relative to the base materials

Market outlook of mineral-organic fertilizers in Brazil.

The aim of this work is to identify producers of organic-mineral fertilizers in Brazil and analyze the characteristics of the manufactured products

Ortorretificação e classificação de imagens dos satélites de alta resolução World View2 e GeoEye.

In the processing of high-resolution images there are still difficulties. And, due to the fact of specific software for treating high resolution images presents high cost, it is necessary to test different types of classifiers and parameters available in softwares low cost or free market to classify high-resolution images. Based on these considerations, the present study was developed to orthorectify and to test different algorithms to classify high resolution images, in this case images of satellite Word View2 and GeoEye. There were tested the following supervised classifiers available in ENVI 4.8 software: Spectral Angle Mapper, Maximum Likelihood, Mahalanobis Distance, Minimum Distance and Parallelepiped, applying them to sampled areas of two watersheds included in the Atlantic Forest in the state of Rio de Janeiro. The results showed that the best classifier for most classes was the Maximum Likelihood (MAXVER) to both images and watersheds. In general, the greatest possibility of confusion was found between the classes: Initial Vegetation and Advanced to Medium Vegetation (0.20), Advanced to Medium Vegetation and Banana (0.28), Initial Vegetation and Agriculture (0.29), Initial Vegetation and Banana (0.38), Banana and Agriculture (0.50), Pasture and Agriculture (0.80). The MAXVER was the classifier that presented best Overall Accuracy (65,38% and 63,165 to each sampled area) and Kappa Coefficient (0,60 and 0,57). But, these values were considered unsatisfactory.Pages: 1379-138

Orbital Magnetism in Ensembles of Parabolic Potentials

We study the magnetic susceptibility of an ensemble of non-interacting electrons confined by parabolic potentials and subjected to a perpendicular magnetic field at finite temperatures. We show that the behavior of the average susceptibility is qualitatively different from that of billiards. When averaged over the Fermi energy the susceptibility exhibits a large paramagnetic response only at certain special field values, corresponding to comensurate classical frequencies, being negligible elsewhere. We derive approximate analytical formulae for the susceptibility and compare the results with numerical calculations.Comment: 4 pages, 4 figures, REVTE