This paper considers the pipeline network design problem (PND) in ethanol transportation, with a view to providing robust and efficient computational tools to assist decision makers in evaluating the technical and eco...This paper considers the pipeline network design problem (PND) in ethanol transportation, with a view to providing robust and efficient computational tools to assist decision makers in evaluating the technical and economic feasibility of ethanol pipeline network designs. Such tools must be able to address major design decisions and technical characteristics, and estimate network construction and operation costs to any time horizon. The specific context in which the study was conducted was the ethanol industry in Sao Paulo. Five instances were constructed using pseudo-real data to test the methodologies developed.展开更多
In the search for renewable energy sources, solar energy appears, among others, as a powerful alternative;mainly for those countries located at Earth’s equatorial region. This is the case of a Fresnel device that use...In the search for renewable energy sources, solar energy appears, among others, as a powerful alternative;mainly for those countries located at Earth’s equatorial region. This is the case of a Fresnel device that uses solar radiation to warm-up the air;for instance, within saunas. Authors coined the term sustainable technological innovation to refer to a technological innovation in accordance to the principles of sustainability. The object of this research was comparing the sustainability of a Fresnel Lens Solar Concentration (FLSC) against the sustainability of other twelve alternatives to generate heat. This article assesses the sustainability of fourteen technological options for heat generation and transfer to saunas in the northwest region of Mexico where temperatures often reach above 45 C and where there is a greater potential for exploiting solar energy. Emergy accounting, economic analysis, and global warming potential are the three indicators considered in quantifying sustainability. Results show that infrared ceramic photovoltaic, infrared carbon photovoltaic and infrared metal photovoltaic are the most sustainable systems. The Fresnel device reached the fourth and tenth position, using electricity from photovoltaic and from grid respectively, among all fourteen assessed devices, respectively. Although Fresnel equipment does not release any global warming gases into the atmosphere, or even it demands low amount of non-renewable resources, 1.40 and 4.47 E17 seJF/yr. it requires high economic investment, 20,800 and 79,600 USD/yr, for the implementation and operation phases, which decrease its sustainability performance compared to twelve other evaluated devices.展开更多
Hydraulic fracturing is widely used to increase oil well production and to reduce formation damage. Reservoir studies and engineering analyses are carried out to select the wells for this kind of operation. As the res...Hydraulic fracturing is widely used to increase oil well production and to reduce formation damage. Reservoir studies and engineering analyses are carried out to select the wells for this kind of operation. As the reservoir parameters have some diffuse characteristics, Fuzzy Inference Systems (FIS) have been tested for these selection processes in the last few years. This paper compares the performance of a neuro fuzzy system and a genetic fuzzy system used for selecting wells for hydraulic fracturing, with knowledge acquired from an operational data base to set the SIF membership functions. The training data and the validation data used were the same for both systems. We concluded that, despite the genetic fuzzy system being a newer process, it obtained better results than the neuro fuzzy system. Another conclusion was that, as the genetic fuzzy system can work with constraints, the membership functions setting kept the consistency of variable linguistic values.展开更多
文摘This paper considers the pipeline network design problem (PND) in ethanol transportation, with a view to providing robust and efficient computational tools to assist decision makers in evaluating the technical and economic feasibility of ethanol pipeline network designs. Such tools must be able to address major design decisions and technical characteristics, and estimate network construction and operation costs to any time horizon. The specific context in which the study was conducted was the ethanol industry in Sao Paulo. Five instances were constructed using pseudo-real data to test the methodologies developed.
文摘In the search for renewable energy sources, solar energy appears, among others, as a powerful alternative;mainly for those countries located at Earth’s equatorial region. This is the case of a Fresnel device that uses solar radiation to warm-up the air;for instance, within saunas. Authors coined the term sustainable technological innovation to refer to a technological innovation in accordance to the principles of sustainability. The object of this research was comparing the sustainability of a Fresnel Lens Solar Concentration (FLSC) against the sustainability of other twelve alternatives to generate heat. This article assesses the sustainability of fourteen technological options for heat generation and transfer to saunas in the northwest region of Mexico where temperatures often reach above 45 C and where there is a greater potential for exploiting solar energy. Emergy accounting, economic analysis, and global warming potential are the three indicators considered in quantifying sustainability. Results show that infrared ceramic photovoltaic, infrared carbon photovoltaic and infrared metal photovoltaic are the most sustainable systems. The Fresnel device reached the fourth and tenth position, using electricity from photovoltaic and from grid respectively, among all fourteen assessed devices, respectively. Although Fresnel equipment does not release any global warming gases into the atmosphere, or even it demands low amount of non-renewable resources, 1.40 and 4.47 E17 seJF/yr. it requires high economic investment, 20,800 and 79,600 USD/yr, for the implementation and operation phases, which decrease its sustainability performance compared to twelve other evaluated devices.
文摘Hydraulic fracturing is widely used to increase oil well production and to reduce formation damage. Reservoir studies and engineering analyses are carried out to select the wells for this kind of operation. As the reservoir parameters have some diffuse characteristics, Fuzzy Inference Systems (FIS) have been tested for these selection processes in the last few years. This paper compares the performance of a neuro fuzzy system and a genetic fuzzy system used for selecting wells for hydraulic fracturing, with knowledge acquired from an operational data base to set the SIF membership functions. The training data and the validation data used were the same for both systems. We concluded that, despite the genetic fuzzy system being a newer process, it obtained better results than the neuro fuzzy system. Another conclusion was that, as the genetic fuzzy system can work with constraints, the membership functions setting kept the consistency of variable linguistic values.
