558 research outputs found
Analysis, Design and Implementation of Biodiesel Projects in Brazil
During the oil crisis of the seventies, Brazil has developed a successful program for gasoline substitution by ethanol (Proálcool). Nowadays the biomass accounts for 27% of total national energy consumed in Brazil and the ethanol participates with 40% of the total national fuel consumption of Otto cycle vehicles. In 2004, the National Program for the Production and Use of Biodiesel (Biodiesel Program) was launched. One priority of the Biodiesel Program is the inclusion of family agriculture and smallholders into the production chain. The Federal University of Viçosa (UFV) has developed a software for the analysis of biodiesel projects with the participation of family agriculture. Results of production chain analysis and economic indicators calculated by the Biosoft system have allowed identifying the regular supply of oil at competitive prices as the key point to the efficiency of biodiesel production chains. The use of oil cake as feedstock is the leverage point of chain performance. The meal sale can lead to a vegetal oil price reduction, without compromising farmers´ income, since they can be able to set up their own oil extraction plants. Coordination is then the critical element and has the potential to improve the performance of both the biodiesel industry and the animal production chain.Agribusiness, Agricultural and Food Policy, Farm Management, Food Consumption/Nutrition/Food Safety, Industrial Organization,
Investment Decision in Vegetable Oil Extraction Plants in North of Minas Gerais – Brazil: An Application of the Analytic Hierarchy Process in a Biodiesel Production Chain
In line with the social objectives of the PNPB (Brazilian Program of Production and Use of Biodiesel) and its “Social Seal” Framework, PETROBRAS has set up a 57 million liter/year biodiesel plant in the semi arid region of North of Minas Gerais State, where the socioeconomics indicators are very unfavorable. Despite the potential to boost the agricultural and agroindustrial sector, the biodiesel plant is using mainly soybean oil from other regions. Funded by the Minas Gerais Government, the ongoing project aims to contribute to the development of oilseed supply chain in the North of Minas Gerais. To deal with these socioeconomic complex decisions, the Analytic Hierarchy Process (AHP) was used. Organization models were proposed for the following production chain: i) castor seed, ii) jatropha, iii) sunflower seed, iv) cotton seed, v) macaw palm and vi) soybean. For each chain, investment alternatives were analysed using the software BiodieselFAO. The organizational models and economic results will be discussed with the stakeholder in a workshop, when the alternatives will be selected. Partial results of the project demonstrate that the lack of trust between the stakeholders is the main challenge to the organization of the production chains. The AHP methodology has been proved to be adequate to accomplish the project objectives. Further researches on production chain modeling and building are, especially for the bioenergy sector, highly opportune
Species fractionation in atomic chains from mechanically stretched alloys.
Bettini et al (2006 Nat. Nanotechnol. 1 182-5) reported the first experimental realization of linear atomic chains (LACs) composed of different atoms (Au and Ag). The different contents of Au and Ag were observed in the chains from what was found in the bulk alloys, which raises the question of what the wire composition is, if it is in equilibrium with a bulk alloy. In this work we address the thermodynamic driving force for species fractionation in LACs under tension, and we present the density-functional theory results for Ag-Au chain alloys. A pronounced stabilization of the wires with an alternating Ag-Au sequence is observed, which could be behind the experimentally observed Au enrichment in LACs from alloys with high Ag content
Traceability for Model Driven, Software Product Line Engineering
Traceability is an important challenge for software organizations. This is true for traditional software development and even more so in new approaches that introduce more variety of artefacts such as Model Driven development or Software Product Lines. In this paper we look at some aspect of the interaction of Traceability, Model Driven development and Software Product Line
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