Como estabelecer com sucesso uma Unidade de Referência Tecnológica em sistema silvipastoril.

Este documento constitui-se em importante contribuição para a instalação de projetos de demonstração relacionados a sistemas silvipastoris, apresentando idéias e sugestões para o sucesso dessas iniciativas. Na perspectiva do desenvolvimento rural sustentável, a integração e a interação dos componentes pecuário, agrícola e florestal são de vital importância, de maneira a contemplar as questões pertinentes à mitigação de seus impactos no meio ambiente e ensejar a máxima biodiversidade possível, o uso conservacionista do solo, a produção e a conservação da água. Assim, a introdução do componente florestal nos sistemas de produção deve se dar num enfoque que não admita mais a separação entre agricultura, pecuária e floresta, mas sim, que promova a integração desses componentes no meio rural, em prol da qualidade de vida, da sustentabilidade e da estabilidade da produção. A compreensão da forma como o componente florestal contribui ou poderia contribuir, nos sistemas de produção existentes, permite o desenvolvimento de trabalhos técnicos para a introdução e/ou melhoramento de práticas florestais e/ou agroflorestais nas propriedades rurais; constituindo-se fundamento para a gestão de boas práticas ambientais. Este documento colabora também para o fortalecimento da competência técnica de profissionais e pessoas vinculados ao desenvolvimento rural, ao apontar estratégias para ações de difusão de tecnologia capaz de mitigar impactos da produção animal de grande porte em condições de pastagem.bitstream/item/190288/1/doc83F.pd

Correlation between Gamma-Ray bursts and Gravitational Waves

The cosmological origin of $\gamma$-ray bursts (GRBs) is now commonly accepted and, according to several models for the central engine, GRB sources should also emit at the same time gravitational waves bursts (GWBs). We have performed two correlation searches between the data of the resonant gravitational wave detector AURIGA and GRB arrival times collected in the BATSE 4B catalog. No correlation was found and an upper limit \bbox{$h_{\text{RMS}} \leq 1.5 \times 10^{-18}$} on the averaged amplitude of gravitational waves associated with $\gamma$-ray bursts has been set for the first time.Comment: 7 pages, 3 figures, submitted to Phys. Rev.

Testing the spectrum hypothesis of problematic online behaviors: A network analysis approach.

The validity of the constructs of problematic Internet or smartphone use and Internet or smartphone addiction has been extensively debated. The spectrum hypothesis posits that problematic online behaviors (POBs) may be conceptualized within a spectrum of related yet distinct entities. To date, the hypothesis has received preliminary support, and further robust empirical studies are still needed. The present study tested the spectrum hypothesis of POBs in an Australian community sample (n = 1,617) using a network analysis approach. Psychometrically validated self-report instruments were used to assess six types of POBs: problematic online gaming, cyberchondria, problematic cybersex, problematic online shopping, problematic use of social networking sites, and problematic online gambling. A tetrachoric correlation matrix was computed to explore relationships between online activities and a network analysis was used to analyze relationships between POBs. Correlations between online activities were positive and significant, but of small magnitude (0.051 ≤ r ≤ 0.236). The community detection analysis identified six distinct communities, corresponding to each POB, with strong relationships between items within each POB and weaker relationships between POBs. These findings provide further empirical support for the spectrum hypothesis, suggesting that POBs occur as distinct entities and with little overlap

Measurements and analysis of the upper critical field Hc2H_{c2} on an underdoped and overdoped La2−xSrxCuO4La_{2-x}Sr_xCuO_4 compounds

The upper critical field $H_{c2}$ is one of the many non conventional properties of high-$T_c$ cuprates. It is possible that the $H_{c2}(T)$ anomalies are due to the presence of inhomogeneities in the local charge carrier density $\rho$ of the $CuO_2$ planes. In order to study this point, we have prepared good quality samples of polycrystalline $La_{2-x}Sr_xCuO_{4}$ using the wet-chemical method, which has demonstrated to produce samples with a better cation distribution. In particular, we have studied the temperature dependence of the second critical field, $H_{c2}(T)$, through the magnetization measurements on two samples with opposite average carrier concentration ($\rho_m=x$) and nearly the same critical temperature, namely $\rho_m = 0.08$ (underdoped) and $\rho_m = 0.25$ (overdoped). The results close to $T_c$ do not follow the usual Ginzburg-Landau theory and are interpreted by a theory which takes into account the influence of the inhomogeneities.Comment: Published versio

Los sistemas silvopastoriles en las regiones subtropicales del Brasil: las actividades de la EMBRAPA.

En Ias regiones subtropicales dei Brasil hay una gran oportunidad para el establecimiento de sistemas silvopastoriles. En esta región, Ias sistemas dominantes de uso de Ia tierra son Ias actividades agrícolas (maíz, soja, trigo, frijol, arroz, etc.) y ganaderas (producción de carne y leche bovina y ovina). Hay presiones económicas y ambientales que actúan en el media rural sobre Ias productores tendientes a adaptar sistemas de uso de Ia tierra más sostenibles. Si bien existen pruebas científicas y ejemplos de aplicación, Ia diversidad de condiciones regionales aconsejan desarrollar más estudios y mecanismos de política pública para promover Ia conversión de Ias pastizales sin árboles aios sistemas silvopastoriles

Calibrating the Dynamic Energy Simulation Model for an Existing Building: Lessons Learned from a Collective Exercise †

Calibration of the existing building simulation model is key to correctly evaluating the energy savings that are achievable through retrofit. However, calibration is a non-standard phase where different approaches can possibly lead to different models. In this study, an existing residential building is simulated in parallel by four research groups with different dynamic simulation tools. Manual/automatic methodologies and basic/detailed measurement data sets are used. The calibration is followed by a validation on two evaluation periods. Monitoring data concerning the windows opening by the occupants are used to analyze the calibration outcomes. It is found that for a good calibration of a model of a well-insulated building, the absence of data regarding the users' behavior is more critical than uncertainty on the envelope properties. The automatic approach is more effective in managing the model complexity and reaching a better performing calibration, as the RMSE relative to indoor temperature reaches 0.3 degrees C compared to 0.4-0.5 degrees C. Yet, a calibrated model's performance is often poor outside the calibration period (RMSE increases up to 10.8 times), and thus, the validation is crucial to discriminate among multiple solutions and to refine them, by improving the users' behavior modeling

ON-LINE CONSISTENCY TESTS FOR BAR DETECTORS

In order to detect gravitational wave signals with resonant bar detectors using Wiener–Kolmogorov (WK) filters, both a model for the power spectrum density (PSD) of the noise and a signal template should be provided. As the analysis is not meant to handle non-gaussian data, we have to discriminate (and constrain to) time periods where the noise follows a quasi-stationary gaussian model. Within these periods, candidate events are selected in the WK filter output, and their fundamental parameters (time of arrival and amplitude) are computed. A necessary and sufficient condition for the reliability of such estimates is the consistency of the signal shape with the template. This is done performing a goodness-of-the-fit test

FeSiB Amorphous Alloy Prepared by Mechano-Synthesis

Abstract. In this work we show that mechano-synthesis is a good method to prepare the FeSiB amorphous alloy starting from Fe, Si, B pure elements with relative atomic composition of 75, 15 and 10%, respectively. We have used a high-energy ball-milling system keeping the material under an Ar atmosphere. The evolution of the microstructure inside the grains is followed by X-ray diffraction and Mössbauer spectroscopy at room temperature. The dependence of crystalline size, lattice parameter and hyperfine parameters on milling time is discussed. Our results show that the milled samples obtained after 10 h of milling contained a bcc structure in the amorphous matrix. After 19 h of milling the sample became fully amorphous