Santos C.,UFMT |
Riyuiti A.,University of Sao Paulo
IEEE Latin America Transactions | Year: 2012
Metadata is data that fully describes the data and the areas they represent, allowing the user to decide on their use as best as possible. Allow reporting on the existence of a set of data linked to specific needs. The use of metadata has the purpose of documenting and organizing a structured organizational data in order to minimize duplication of efforts to locate them and to facilitate maintenance. It also provides the administration of large amounts of data, discovery, retrieval and editing features. The global use of metadata is regulated by a technical group or task force composed of several segments such as industries, universities and research firms. Agriculture in particular is a good example for the development of typical applications using metadata is the integration of systems and equipment, allowing the implementation of techniques used in precision agriculture, the integration of different computer systems via webservices or other type of solution requires the integration of structured data. The purpose of this paper is to present an overview of the standards of metadata areas consolidated as agricultural. © 2005 IEEE.
Borges Jr. J.C.F.,CSL UFSJ |
Anjos R.J.,INMET |
Silva T.J.A.,UFMT |
Lima J.R.S.,Federal Rural University of Pernambuco |
Andrade C.L.T.,Embrapa Milho e Sorgo
Revista Brasileira de Engenharia Agricola e Ambiental | Year: 2012
For high frequency irrigation management, based on climate data, it is desirable to estimate reference evapotranspiration at small time steps. This work aimed at to evaluate the performance of daily reference evapotranspiration estimated by the following methods: FAO-24 Radiation, Priestley-Taylor, Hargreaves-Samani, Camargo-71 and Blaney-Criddle, for Garanhuns-PE micro-region, having FAO Penman-Monteith method as standard. Considering the mean absolute error (MAE), among other statistics, it was verified that the best performance was obtained by the Priestley-Taylor method. Regarding the methods applicable when only temperature data are available, the Hargreaves-Samani showed the best performance, having been calibrated based on the minimization of the MAE.
Correa P.C.,Federal University of Vicosa |
Botelho F.M.,UFMT |
Botelho S.C.C.,Embrapa Agrossilvipastoril |
Revista Brasileira de Engenharia Agricola e Ambiental | Year: 2014
The objectives of this study were to evaluate and to model the isotherms curves obtained by adsorption and desorption processes for the fruits of ripe (cherries) coffee (Coffea canephora), for different psychrometric conditions of the air. For all sorption processes, different conditions of temperature (between 10 and 50 °C) and relative humidity (between 10 and 95%) were used, until the product reached its equilibrium moisture content with the air condition specified. For experimental data of sorption, different mathematical models often use to represent hygroscopicity of agricultural products were adjusted. It was verified that the equilibrium moisture content of the fruits of coffee increased with relative humidity for a given temperature and decreased with increasing temperature for a given relative humidity. The hysteresis, regardless of temperature, was more pronounced for relative humidity of the air between 65 and 75%. The Sigma-Copace model was the best in describing hygroscopicity of the fruits of coffee both in desorption and adsorption. © 2014, Departamento de Engenharia Agricola - UFCG/Cnpq. All rights reserved.
Pereira E.G.,Federal University of Vicosa |
Da Silva J.N.,Federal University of Vicosa |
De Oliveira J.L.,UFMT |
MacHado C.S.,Federal University of Vicosa
Renewable and Sustainable Energy Reviews | Year: 2012
Biomass has been widely recognized as a clean and renewable energy source, with increasing potential to replace conventional fossil fuels in the energy market. The abundance of biomass ranks it as the third energy resource after oil and coal. The reduction of imported forms of energy, and the conservation of the limited supply of fossil fuels, depends upon the utilization of all other available fuel energy sources. Energy conversion systems based on the use of biomass are of particular interest to scientists because of their potential to reduce global CO 2 emissions. With these considerations, gasification methods come to the forefront of biomass-to-energy conversions for a number of reasons. Primarily, gasification is more advantageous because of the conversion of biomass into a combustible gas, making it a more efficient process than other thermochemical processes. Biomass gasification has been studied widely as an efficient and sustainable technology for the generation of heat, production of hydrogen and ethanol, and power generation. Renewable energy can have a significant positive impact for developing countries. In rural areas, particularly in remote locations, transmission and distribution of energy generated from fossil fuels can be difficult and expensive, a challenge that renewable energy can attempt to correct by facilitating economic and social development in communities. This paper aims to take stock of the latest technologies for gasification. © 2012 Elsevier Ltd. All rights reserved.
Roboredo D.,Mato Grosso State University |
Maia J.C.S.,UFMT |
de Oliveira O.J.,Federal University of Minas Gerais |
Engenharia Agricola | Year: 2010
Soil compaction is a problem that interferes in root growth and crop production. This study was conducted in the experimental station of Centro Federal de Educação Tecnológica of Cuiabá (CEFET), in Santo Antonio do Leverger - MT, Brazil. The aim was to evaluate the cone index of the Distrophic Red Latosol in function of different water levels in two depths, by using a constant speed penetrometer and an impact one, correlating them with the soil density. The design was made of randomized blocks with eight treatments and five replications, arranged by split plots, with four bands of soil water content in the plots: range 1 (0.1883 to 0.2354 m3 m-3); range 2 (0.2355 to 0.2544 m3 m-3); range 3 (0.2545 to 0.2702 m3 m-3) and range 4 (0.2703 to 0.3177 m3 m-3), and two depths of sampling like subplots (0.05 to 0.10 m and 0.15 to 0.20 m). From the results it was found that: i) the penetrometers showed significant positive correlation with the soil density; ii) the impact penetrometer presented the highest soil strength.