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981.
The aim of this paper is to evaluate the soybean production and industrial processing stages in Brazil using the emergy accounting methodology and economic cost and revenue estimation in order to assess the environmental and economic inputs to the soybean chain and to evaluate the amount of emergy and nutrients exported to European countries. The main findings of this work were that the agricultural stage uses the highest amount of resources. The emergy exchange ratio shows that farmers are delivering around six times more emergy in the soybean that is being sold than the emergy they are receiving with the money paid for it. Results demonstrate that producing raw soybean and soy meal for international markets makes Brazil lose a great amount of emergy and nutrients. Besides that, soybean production is nowadays providing low profitability to farmers because of low prices for soybean products and high prices for the chemicals used in soybean farming. Therefore, at present conditions, exporting soybean as a commodity results in low profit per unit of area. 相似文献
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Rogério Cerávolo Calia Fábio Müller Guerrini Mário de Castro 《Journal of Cleaner Production》2009,17(15):1303-1310
The diffusion of Pollution Prevention faces organizational barriers as for instance resistance to change, insufficient support from decision-makers, unclear project leadership, insufficient employee accountability and inflexible organizational structures. To understand how to overcome such barriers, the performance of a Pollution Prevention program of a multinational corporation is analyzed. The quantitative analyses of 2096 Pollution Prevention projects conducted between 1995 and 2007 support the conclusion that the performance of the Pollution Prevention program increased after the implementation of the Six Sigma program. Moreover, the analyses of 1906 Pollution Prevention projects and 31,133 Six Sigma projects for cost reduction in 27 countries indicate that in countries where the implementation of Six Sigma is more expressive, pollution is prevented more than in countries with less expressive Six Sigma implementation. In fact, the Six Sigma implementation improved the organizational capability for data based project management. Therefore, comparing six years before and six years after the Six Sigma implementation, the total number of Pollution Prevention projects recognized increased 6.9 times and the total amount of pollution prevented increased by 62%. The qualitative analysis describes how the Six Sigma program interacts with the Pollution Prevention program in the studied company. 相似文献
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The significance of waste management systems in recent years increased due to the growing problems of waste management chains affecting the daily lives of millions of people and the impact on the environment. Several promising approaches have been developed in the past few years. One of them is the waste management system modelling using reliability, availability, maintainability and safety software. This paper analyses and evaluates this approach. The main goal is to provide quantitative forecasts for various performance measures of waste management systems. They include availability, downtimes, number of failures, and cost. Evaluation of these measures is important for optimal decision making. The system design should both maximise the system performance leading to cleaner processing and minimise the overall cost within the allowable constraints. The effectiveness of this methodology is demonstrated through a case study. 相似文献
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