Alexandre Bevilacqua Leoneti

Saneamento básico no Brasil: considerações sobre investimentos e sustentabilidade para o século XXI

Since the late 1950th century until the end of the month, the investment in basic sanitation in Brazil occurred occasionally in some specific periods, with an emphasis on the 1970 and 1980. As a result, Brazil is still characterized by great inequality and low access, particularly regarding the collection and sewage treatment. Currently, the sector has received greater government attention and there is a significant amount of resources to be invested. However, it is necessary that these investments are sustainable. Thus, this research sought through a descriptive and exploratory, were performed to see how investment in basic sanitation in Brazil, with emphasis on sewage treatment, and discuss how resources are being made available to meet the legal aspects which are submitted to municipalities beginning of this century. For this purpose, were used as primary sources of unstructured interviews with technicians and sanitation sector as secondary sources, information was collected on the websites of major public and private agencies that have a bearing on the sanitation in Brazil. We identified potential flaws in the planning of the sector over recent years, and have been found evidence that points to possible flaws in the evaluations of the investments being made, not considered their sustainability. As a contribution, we tried to identify some new forms of management in sanitation, which could help municipal managers in achieving its goals.

CONSIDERATIONS REGARDING THE CHOICE OF RANKING MULTIPLE CRITERIA DECISION MAKING METHODS

Various methods, known as Multiple Criteria Decision Making Methods (MCDM), have been proposed to assist decision makers in the process of ranking alternatives. Given the variability of available methods, choosing an MCDM ranking method is a difficult task. There are key factors in the process of choosing an MCDM method such as: (i) available time; (ii) effort required by a given approach; (iii) importance of accuracy; (iv) transparency necessity; (v) conflict minimization necessity; and (vi) facilitators skill with the method. However, the problem is further increased by the knowledge that the solution of MCDM ranking methods may be sensitive to slight variations in entrance data and, in some cases, might replace the best alternative for the worst when the weightings for the criteria are changed. Some researchers have addressed this problem through different approaches, including the evaluation of MCDM ranking methods in the sense of predicting the initial rankings given by the decision maker. The objective of this study is to propose an empirical experiment to evaluate the propensity for initial ranking prediction of the principal MCDM ranking methods, namely: SAW, TOPSIS, ELECTRE III, PROMETHEE II and TODIM. The study also aimed to assess possible common ranking problems in MCDM methods, such as reversibility, found in the literature. It was found that just up to 20% of initial ranking order was predicted entirely correct by some of the methods. It was also found that just a few methods did not present internal ranking inconsistency. The results of this study and those found in the literature give a warning regarding the choice of MCDM ranking methods. It is suggested that special care must be taken in the choice of methods and, besides axiomatic comparisons, ranking comparisons could be a useful way to enhance the decision making process, since MCDM methods are tools for learning about the problem and do not prescribe solutions.

The methylic versus the ethylic route: considerations about the sustainability of Brazilian biodiesel production

AbstractBrazil is considered one of the world’s leading producers of biofuels given the predominance of ethanol fuel in its energy matrix. However, despite the prominence of Brazil in ethanol production, the vast majority of biodiesel production plants in Brazil use methanol instead of ethanol as the alcohol for transesterification reaction, as is generally the case in the rest of the world. The aim of this paper is therefore to examine the transesterification process in the Brazilian biodiesel production in terms of sustainability. In this regard, it was necessary to evaluate the way in which the industrial process is currently carried out, the role of government incentives or subsidies for the use of ethanol to produce biodiesel, and the investments of companies in technology development for the same purpose. This study presents indications that the development of the biodiesel market in Brazil is still oriented toward a production model which is inconsistent with the environmental and social aspects of sustainability.

O equilíbrio de Nash como uma solução para o conflito entre eficiência e custo na escolha de sistemas de tratamento de esgoto sanitário com o auxílio de um modelo de tomada de decisão

A escolha de estacoes de tratamento de esgoto pode, dentre outras coisas, envolver um conflito entre a eficiencia e o custo, pois para o menor custo possivel esta escolha tambem devera satisfazer varias exigencias ambientais. Para auxiliar na escolha de uma estacao de menor custo, um modelo baseado em tecnicas de tomada de decisao foi desenvolvido por Oliveira (2004). Todavia, se nao forem levados em consideracao os outros criterios envolvidos, a interacao entre os tomadores de decisao e suas respectivas estrategias podem fazer com que a escolha do sistema de tratamento nao seja a mais adequada. Para estes casos, o equilibrio de Nash pode oferece uma solucao, construida com base na interacao entre os jogadores, a qual poderia satisfazer razoavelmente os interesses conflitantes. Desta forma, o objetivo desta pesquisa foi, com base nos dados de saida do modelo de Oliveira (2004), encontrar o equilibrio de Nash para propor uma solucao para o conflito entre a eficiencia e o custo nas escolhas do sistema de tratamento de esgoto sanitario. A comparacao entre os diferentes resultados alcancados, quando apenas considerado o criterio de menor custo ou de maior eficiencia, demonstrou que a adocao do equilibrio de Nash pode ser uma alternativa viavel para solucionar o conflito entre a eficiencia e o custo nas escolhas das estacoes de tratamento de esgoto sanitario.

A Deviation Index Proposal to Evaluate Group Decision Making Based on Equilibrium Solutions

The equilibrium proposed by Nash provides a basis from which group decisions can be selected. This kind of choice establishes a situation in which none of the participants will have any incentive to change their strategy if they are acting rationally, which is the major assumption of game theory. Leoneti proposed a utility function that allows multi-criteria problems to be modeled as games in order to find alternatives that meet the Nash equilibrium conditions for solving conflicts in group decision-making process. The objective of this research was to propose a deviation index from the theoretical rational decision (the Nash equilibrium solution) and to discuss the use of this index as an indicator of the theoretical rationality deviation. In accordance with other results presented in the literature, it was found that the group might not always choose this alternative, deviating from the equilibrium solutions, measured here by a deviation index.

Um método e um programa para a formação e logística de equipes de trabalho

Este artigo apresenta um metodo para a formacao e logistica de equipes de trabalho. O metodo proposto resolve um modelo matematico em variaveis binarias 0/1, desenvolvido com base no modelo de designacao generalizada, de forma a minimizar o custo do vale-transporte e constituir equipes com um numero predefinido de agentes. O programa correspondente foi escrito em Excel-Solver e testado numa empresa prestadora de servicos terceirizados presente em mais de 200 cidades brasileiras.