997 resultados para Cultural efficiency


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The aim of this study was to analyze, under the energetic point of view, the cultivation of corn in three management systems (low, medium and high-tech), using two landrace varieties ('Argentino' and 'BR da Várzea'), a double hybrid cultivar (SHS 4080) and a simple hybrid (IAC 8333). Five performance indicators were used: energy efficiency, liquid cultural energy, cultural efficiency, energy balance and productive energy efficiency. From the perspective of family farming, it was verified the largest social importance of the systems under low and medium levels of technology, due to the increase employment capacity of rural labor. The liquid cultural energy and energy balance were more favorable for the system under high technological level, unlike cultural efficiency and productive energy efficiency, which were significantly higher for medium and low technological levels. The variety 'Argentino' showed lower productive energy efficiency. The variety 'BR da Várzea', on the other hand, presented the potential to generate energy as much as the hybrids. In general, the biggest sustainability in the corn crop was achieved when the management system under medium and lower levels of technology were used.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Pós-graduação em Agronomia (Energia na Agricultura) - FCA

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Pós-graduação em Agronomia (Energia na Agricultura) - FCA

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Pós-graduação em Agronomia (Energia na Agricultura) - FCA

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Pós-graduação em Agronomia (Energia na Agricultura) - FCA

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This paper, having as a hypothesis that greater energetic inputs don't keep ratio with economical outputs, has tried to study the economical and energetic flows in the maize cultivation to several production systems used in Ipanema Settling Area I, having as analysis instrument the indexes of Cultural, Energetic, Economical efficiency, which were added to the methodological proposal of Cultural Economical and Energetic Economical Efficiency indexes, built for probability settings. Four different systems have been identified: "A", "B", "C" and "D". The energetic expenditure were, respectively, 4,836.19 MJ x ha-1, 4,4647.17 MJ x ha-1, 4,639.49 MJ x ha-1 and 4,450.47 MJ x ha-1. In "A", where the use of machines is more intensive, the participation of biological source energy was 23.26%, whereas the ones of fossil origin are 76.74%. The "D" system has the greatest Cultural Efficiency, with average index of 16.26, whereas "A" showed the lowest Cultural Efficiency indexes, with average values of 14.83. For the analysis of the Energetic Efficiency, that indicates the dependence of energy from non renewable sources, the highest index was the "D" system with an average index of 53.84. The Economical Efficiency Indexes, which ranged from 1.84 to 1.96, show that all systems are efficient. The "D" system, with index equal to 8.84, showed the highest index of Economical Cultural efficiency. The Economical Energetic analysis for "A", "B", "C" and "D" systems, has resulted, respectively, in the following indexes: 21.14 ; 23.86 ; 22.87 and 29.26. Through the outcome analysis, it was concluded that the more intensive use of energy from nonrenewable sources ("A" system) didn't necessarily mean a higher efficiency when compared to "D" (labor intensive), what comes to prove the paper's initial hypothesis.

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The objective of this study is to determine the economical and energetic efficiency of the castor bean culture in "Zona da Mata" and South of Minas Gerais. Through the method of simulation "Monte Carlo", we verified the probabilities of occurrence of the economical, cultural and energetic efficiency indexes. In relation to the production systems of castor bean in Minas Gerais in the season 2005/2006, we established that the variables price and productivity were the most noticeable for the producers from "Zona da Mata", while in the South of Minas it was productivity. We verified that the probability of the economical efficiency index to be lower than one was 43,26% for the producers from "Zona da Mata" and 39,57% for the ones from the South of Minas. The medium price received covered the medium costs of production. However, we observed that the medium costs in these regions of Minas Gerais, were over the minimum price. Regarding the energetic analysis, the results showed that the systems in the regions studied in Minas Gerasi, presented average of cultural efficiency indexes of 8,26 and 18,89. We concluded that despite the result being favorable from the energetic point of view, from the economical sustainability point of view there is the need of a more effective support policy for the castor bean, taking into consideration that the expectations of the producers with PNPB were not confirmed.

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The objective of this work was to evaluate the energy and economic efficiency indexes per unit of cotton agro-ecosystem area in family production systems of Paraguay and Brazil; and, to establish a relationship between the energy and economic. Typologies presented by the Program to Support Small Cotton Holdings (Paraguay), and by the National Program for Strengthening Family Agriculture (Brazil). Family systems of the two countries were identified; these are located from Paraguay (San Juan–CA) and from Brazil (Leme–SP). To construct the energy expenditure structure of the cotton agro-ecosystem, as well as to assess the economic efficiency, the mean values obtained were considered, when they presented similarities in production systems and they were within the typology proposed in this study. From the technical itinerary observed the Paraguayan agro-ecosystem depended (fossil fuel 56.76%) and industrial source (35.99%). Thus, the energy balance of the agricultural stage was established, which attained a value of 17,740.69 MJ ha-1; an energy efficiency of 5.28, and a cultural efficiency of 3.04. The Brazilian agro-ecosystem depended on energy from industrial source (insecticides 39.82%) and from fossil fuel (33.59%); it reached an energy balance of 19,547.88 MJ ha-1; an energy efficiency of 2.12, and a cultural efficiency index of 0.71. In the economic and energy indicator ratio, with regard to the months referring to the harvest time, that is to say, March, April, and May, the maximum economic efficiency indicator of paraguay was attained in the month of May (1,00), and from Brazil in the month of May (1,71). Both production systems analyzed were presented efficient, however, dependent of external circumstances and non-renewable energy sources.

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The objective of this work was to evaluate the energy and economic efficiency indexes per unit of cotton agro-ecosystem area in family production systems of Paraguay and Brazil; and, to establish a relationship between the energy and economic. Typologies presented by the Program to Support Small Cotton Holdings (Paraguay), and by the National Program for Strengthening Family Agriculture (Brazil). Family systems of the two countries were identified; these are located from Paraguay (San Juan–CA) and from Brazil (Leme–SP). To construct the energy expenditure structure of the cotton agro-ecosystem, as well as to assess the economic efficiency, the mean values obtained were considered, when they presented similarities in production systems and they were within the typology proposed in this study. From the technical itinerary observed the Paraguayan agro-ecosystem depended (fossil fuel 56.76%) and industrial source (35.99%). Thus, the energy balance of the agricultural stage was established, which attained a value of 17,740.69 MJ ha-1; an energy efficiency of 5.28, and a cultural efficiency of 3.04. The Brazilian agro-ecosystem depended on energy from industrial source (insecticides 39.82%) and from fossil fuel (33.59%); it reached an energy balance of 19,547.88 MJ ha-1; an energy efficiency of 2.12, and a cultural efficiency index of 0.71. In the economic and energy indicator ratio, with regard to the months referring to the harvest time, that is to say, March, April, and May, the maximum economic efficiency indicator of paraguay was attained in the month of May (1,00), and from Brazil in the month of May (1,71). Both production systems analyzed were presented efficient, however, dependent of external circumstances and non-renewable energy sources.

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The aim of this work was to proceed, from the energetic point of view, an analysis of a corn agroecosystem, on the direct planting, located at Pirituba II rural workers placement project, Área III, city of Itaberá/SP. The energetic analysis mesured all operations, together with its fisical demands, the inputs and produced grains, classifying them within their respective flux, based on the definition of energy inputs and outputs, converting them into energetic equivalents and, so, determining the energetic matrix of de agroecosystem. The caloric index used were cultural efficiency and cultural liquid energy. The results showed the dependence of the studied systems on the chemical energy sources, from fertilizers (39,49%), agrotoxics (27,74%), and fossile energy of diesel (24,94%). The energetic values of the direct and indirect energy showed a very big difference between them, what means that the energy sources used in the system are not balanced. The cultural efficiency found was 12,86 and cultural liquid energy got to 115.025,92 MJ x ha-1. Later on, obtained data was compared to already existing data in Bueno (2002), who researched conventional planting system. The cultural inputs of both systems were energeticaly different: 9.696,97 MJ x ha-1 (direct planting), e 8.783,78 MJ x ha-1 (convencional planting). The outputs had very different results: 124.722,89 e 79.118,38 MJ x ha-1, respectively. So, we had much more cultural liquid energy on the studied system: 115.025,92 MJ x ha-1, compared to convencional system: 70.334,60 MJ x ha-1. The energectic loss of nitrogened fertilizers contributed for the high energetic loss of both energetic studied matrices. There are few contribution from biological energy source in both systems.

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We study market reaction to the announcements of the selected country hosting the Summer and Winter Olympic Games, the World Football Cup, the European Football Cup and World and Specialized Exhibitions. We generalize previous results analyzing a large number and different types of mega-events, evaluate the effects for winning and losing countries, investigate the determinants of the observed market reaction and control for the ex ante probability of a country being a successful bidder. Average abnormal returns measured at the announcement date and around the event are not significantly different from zero. Further, we find no evidence supporting that industries, that a priori were more likely to extract direct benefits from the event, observe positive significant effects. Yet, when we control for anticipation, the stock price reactions around the announcements are significant.

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Dissertação de Natureza Científica para obtenção do grau de Mestre em Engenharia Civil na Área de Especialização de Edificações

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The Azores archipelago is a zone with a vast cultural heritage, presenting a building stock mainly constructed in traditional stone masonry. It is known that this type of construction exhibits poor behaviour under seismic excitations; however it is extensively used in seismic prone areas, such as this case. The 9th of July of 1998 earthquake was the last seismic event in the islands, leaving many traditional stone constructions severely damaged or totally destroyed. This scenario led to an effort by the local government of improving the seismic resistance of these constructions, with the application of several reinforcement techniques. This work aims to study some of the most used reinforcement schemes after the 1998 earthquake, and to assess their effectiveness in the mitigation of the construction’s seismic vulnerability. A brief evaluation of the cost versus benefit of these retrofitting techniques is also made, seeking to identify those that are most suitable for each building typology. Thus, it was sought to analyze the case of real structures with different geometrical and physical characteristics, by establishing a comparison between the seismic performance of reinforced and non-reinforced structures. The first section contains the analysis of a total of six reinforcement scenarios for each building chosen. Using the recorded 1998 earthquake accelerograms, a linear time-history analysis was performed for each reinforcement scenario. A comparison was then established between the maximum displacements, inter-storey drift and maximum stress obtained, in order to evaluate the global seismic response of each reinforced structure. In the second part of the work, the examination of the performance obtained in the previous section, in relation to the cost of implementing each reinforcement technique, allowed to draw conclusions concerning the viability of implementing each reinforcement method, based on the book value of the buildings in study.

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Business organisations are excellent representations of what in physics and mathematics are designated "chaotic" systems. Because a culture of innovation will be vital for organisational survival in the 21st century, the present paper proposes that viewing organisations in terms of "complexity theory" may assist leaders in fine-tuning managerial philosophies that provide orderly management emphasizing stability within a culture of organised chaos, for it is on the "boundary of chaos" that the greatest creativity occurs. It is argued that 21st century companies, as chaotic social systems, will no longer be effectively managed by rigid objectives (MBO) nor by instructions (MBI). Their capacity for self-organisation will be derived essentially from how their members accept a shared set of values or principles for action (MBV). Complexity theory deals with systems that show complex structures in time or space, often hiding simple deterministic rules. This theory holds that once these rules are found, it is possible to make effective predictions and even to control the apparent complexity. The state of chaos that self-organises, thanks to the appearance of the "strange attractor", is the ideal basis for creativity and innovation in the company. In this self-organised state of chaos, members are not confined to narrow roles, and gradually develop their capacity for differentiation and relationships, growing continuously toward their maximum potential contribution to the efficiency of the organisation. In this way, values act as organisers or "attractors" of disorder, which in the theory of chaos are equations represented by unusually regular geometric configurations that predict the long-term behaviour of complex systems. In business organisations (as in all kinds of social systems) the starting principles end up as the final principles in the long term. An attractor is a model representation of the behavioral results of a system. The attractor is not a force of attraction or a goal-oriented presence in the system; it simply depicts where the system is headed based on its rules of motion. Thus, in a culture that cultivates or shares values of autonomy, responsibility, independence, innovation, creativity, and proaction, the risk of short-term chaos is mitigated by an overall long-term sense of direction. A more suitable approach to manage the internal and external complexities that organisations are currently confronting is to alter their dominant culture under the principles of MBV.