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Cano-Crespo A.,Potsdam Institute for Climate Impact Research | Cano-Crespo A.,Humboldt University of Berlin | Oliveira P.J.C.,Potsdam Institute for Climate Impact Research | Boit A.,Potsdam Institute for Climate Impact Research | And 2 more authors.
Journal of Geophysical Research G: Biogeosciences | Year: 2015

Understanding to what extent different land uses influence fire occurrence in the Amazonian forest is particularly relevant for its conservation. We evaluate the relationship between forest fires and different anthropogenic activities linked to a variety of land uses in the Brazilian states of Mato Grosso, Pará, and Rondônia. We combine the new high-resolution (30 m) TerraClass land use database with Moderate Resolution Imaging Spectroradiometer burned area data for 2008 and the extreme dry year of 2010. Excluding the non-forest class, most of the burned area was found in pastures, primary and secondary forests, and agricultural lands across all three states, while only around 1% of the total was located in deforested areas. The trend in burned area did not follow the declining deforestation rates from 2001 to 2010, and the spatial overlap between deforested and burned areas was only 8% on average. This supports the claim of deforestation being disconnected from burning since 2005. Forest degradation showed an even lower correlation with burned area. We found that fires used in managing pastoral and agricultural lands that escape into the neighboring forests largely contribute to forest fires. Such escaping fires are responsible for up to 52% of the burned forest edges adjacent to burned pastures and up to 22% of the burned forest edges adjacent to burned agricultural fields, respectively. Our findings call for the development of control and monitoring plans to prevent fires from escaping from managed lands into forests to support effective land use and ecosystem management. ©2015. American Geophysical Union. All Rights Reserved. Source


Ricci M.C.,Brazilian Institute for Space Research
World Academy of Science, Engineering and Technology | Year: 2010

A known iterative computational procedure is used for internal normal ball loads calculation in statically loaded single-row, angular-contact ball bearings, subjected to a known thrust load, which is applied in the inner ring at the geometric bearing center line. Numerical aspects of the iterative procedure are discussed. Numerical examples results for a 218 angular-contact ball bearing have been compared with those from the literature. Twenty figures are presented showing the geometrical features, the behavior of the convergence variables and the following parameters as functions of the thrust load: normal ball loads, contact angle, distance between curvature centers, and normal ball and axial deflections between the raceways. Source


Schroeder W.,University of Maryland University College | Oliva P.,University of Maryland University College | Giglio L.,University of Maryland University College | Quayle B.,U.S. Department of Agriculture | And 2 more authors.
Remote Sensing of Environment | Year: 2015

The gradual increase in Landsat-class data availability creates new opportunities for fire science and management applications that require higher-fidelity information about biomass burning, improving upon existing coarser spatial resolution (≥. 1. km) satellite active fire data sets. Targeting those enhanced capabilities we describe an active fire detection algorithm for use with Landsat-8 Operational Land Imager (OLI) daytime and nighttime data. The approach builds on the fire-sensitive short-wave infrared channel 7 complemented by visible and near-infrared channel 1-6 data (daytime only), while also expanding on the use of multi-temporal analysis to improve pixel classification results. Despite frequent saturation of OLI's fire-affected pixels, which includes radiometric artifacts resulting from folding of digital numbers, our initial assessment based on visual image analysis indicated high algorithm fidelity across a wide range of biomass burning scenarios, gas flares and active volcanoes. Additional field data verification confirmed the sensor's and algorithm's ability to resolve fires of significantly small areas compared to current operational satellite fire products. Commission errors were greatly reduced with the addition of multi-temporal analysis tests applied to co-located pixels, averaging less than 0.2% globally. Because of its overall quality, Landsat-8/OLI active fire data could become part of a network of emerging earth observation systems providing enhanced spatial and temporal coverage of biomass burning at global scales. © 2015. Source


De Vasconcelos L.G.,Brazilian Institute for Space Research | Dos Santos R.D.C.,Brazilian Institute for Space Research | Baldochi L.A.,Federal University of Itajuba
Proceedings of the 13th International Conference WWW/Internet 2014, ICWI 2014 | Year: 2014

With the increasing use of the Internet, the Web has become the predominant means by which people obtain information. However, due to the fast growth of the amount and (sometimes competing) sources of resources available on the Web, users want to find information quickly and efficiently. Currently, web personalization has been explored in order to encourage user's feedback, improve usability and provide interesting content. In the literature, the most common approach is to analyze server logs, which contain information about what pages the user accesses during browsing. However, client logs contain more information about the user navigation. The amount of data of the client logs is significantly greater than the amount of server logs, and this is one factor that discourages analysis of client logs. In this paper, an approach is presented to classify the level of user's experience in real time, using indices of efficiency and effectiveness. The proposed approach, called RUX (Real-time User eXperience), contains an efficient algorithm for analyzing the user's behavior of web applications in real time using client logs. RUX focuses on the paths that a user goes through during the interaction, comparing them to previously defined tasks. RUX approach can be used by application developer to consume the classification of user's experience in real time, previously programming actions that can be taken. Experimental results show that the approach is efficient for aspects of data collection, latency and scalability. Source


Ricci M.C.,Brazilian Institute for Space Research
World Academy of Science, Engineering and Technology | Year: 2010

An alternative iterative computational procedure is proposed for internal normal ball loads calculation in statically loaded single-row, angular-contact ball bearings, subjected to a known thrust load, which is applied in the inner ring at the geometric bearing center line. An accurate method for curvature radii at contacts with inner and outer raceways in the direction of the motion is used. Numerical aspects of the iterative procedure are discussed. Numerical examples results for a 218 angular-contact ball bearing have been compared with those from the literature. Twenty figures are presented showing the geometrical features, the behavior of the convergence variables and the following parameters as functions of the thrust load: normal ball loads, contact angle, distance between curvature centers, and normal ball and axial deflections. Source

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