4,175 research outputs found
Evaluating the most promising sites for wind energy development in Arizona USA: Working paper series--05-09
During the summer of 2003, the state of Arizona took delivery of a set of high-resolution wind energy maps. After applying various exclusions, the developable wind energy potential is 23,290 MW of class 3 or higher, 2,630 MW of class 4 or higher, and 775 MW of class 5 or higher winds. Having determined the potential wind resource, the geographical information system data supplied with the wind maps was used to create a wind resource inventory and to systematically identify the most promising sites for wind energy development. In addition to wind energy potential, proximity to transmission lines and roads, and land ownership were considered in this analysis. Following that, the cost of energy was estimated at a few geographically diverse sites, including class 3, 4, and 5 wind resource areas, at a hub height of 70 m. These estimates revealed that the real levelized cost of energy in 2005 dollars ranged from 4.21 to 5.04 cents per kWh, as the wind class varies from 5 to 3. This paper documents the findings of the wind mapping process, describes the method and results of evaluating the most promising sites for wind development, and presents the cost of energy results
Resultados preliminares sobre o comportamento de cultivares e hídridos de milho normal em solos de cerrado na região de Brasília.
Resultados obtidos em condições de campo durante o ano agrícola de 1975/76, sobre o comportamento de 30 cultivares e híbrido de milho
Automated image analysis of lung branching morphogenesis from microscopic images of fetal rat explants
Article ID 820214Background. Regulating mechanisms of branching morphogenesis of fetal lung rat explants have been an essential tool for molecular research. This work presents a new methodology to accurately quantify the epithelial, outer contour, and peripheral airway buds of lung explants during cellular development from microscopic images. Methods. The outer contour was defined using an adaptive and multiscale threshold algorithm whose level was automatically calculated based on an entropy maximization criterion. The inner lung epithelium was defined by a clustering procedure that groups small image regions according to the minimum description length principle and local statistical properties. Finally, the number of peripheral buds was counted as the skeleton branched ends from a skeletonized image of the lung inner epithelia. Results. The time for lung branching morphometric analysis was reduced in 98% in contrast to the manual method. Best results were obtained in the first two days of cellular development, with lesser standard deviations. Nonsignificant differences were found between the automatic and manual results in all culture days. Conclusions. The proposed method introduces a series of advantages related to its intuitive use and accuracy, making the technique suitable to images with different lighting characteristics and allowing a reliable comparison between different researchers.The authors acknowledge Foundation for Science and Technology (FCT), Portugal, for the fellowship with the references: SFRH/BD/74276/2010 and SFRH/BPD/46851/2008
Investigating the causes of variability in the intensity of hydrothermal alteration of ocean crust formed at intermediate to fast spreading rates
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