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The two-dimensional hydrodynamic flood models are computationally expensive, especially in large-scale watersheds, which limits their application when several simulation runs are required or in large-scale catchments. More recently, the literature presented a significant increase in the use of Deep Learning as an alternative to hydrodynamic models because of their computational efficiency. However, studies show that Artificial Neural Networks (ANN) applications for flood prediction lack the ability to predict floods outside the training datasets satisfactorily. In this study, we used a conditional generative adversarial network (cGAN) aiming to generalize pluvial flood predictions (cGAN-Flood) in catchments not included in the training dataset. Our approach uses two generators to solve a rain-on-grid problem by first identifying wet cells and then calculating the water depths. cGAN-Flood distributes a target flood volume (vt) in a given catchment, which can be calculated via water balance from any hydrological simulations. Our approach was trained on ten and tested on five urban catchments. The testing areas have distinct characteristics and were compared to HEC-RAS outputs for different rainfall magnitudes and surface roughness. The averages of the root square mean error (RSME) and critical success index (CSI) were 0.12m and 70.1%, respectively. The successful water depths predictions in the testing areas show that cGAN-Flood can generalize. cGAN-Flood, combined with an SWMM model to compute vt, was 250 times faster than HEC-RAS. Due to its computational efficiency and accuracy, cGAN-Flood can be applied when fast simulations are necessary, and it can be a viable for flood forecasts in large-scale watersheds., The 28th IUGG General Assembly (IUGG2023) (Berlin 2023) more...

Renewable energy promotion based on bioenergy must avoid the competition for land between different uses or crops to be more sustainable and to meet the global demand. In this sense, making available for local bioenergy deployment marginal and abandoned lands could help to several key issues simultaneously, such as sustainable energy production and mitigation of rural abandonment. Cardoon (Cynara cardunculus L.) is a well-adapted crop to Mediterranean rainfed conditions, being able to be grown in marginal and abandoned lands. Cardoon cultivated in marginal lands is characterized by low inputs requirements and lesser yields. This study is focused on the environmental behavior of five cardoon scenarios and the external cost associated with three impact categories: climate change, acidification and terrestrial eutrophication. This study analyses the uses of agricultural bioenergy crops using two different conversion technologies: heat and power production and two processes to convert biomass on heat: domestic heat combustion and district heating. The results for the climate change category show that the agricultural phase generates the most of the impacts from 56-62% for heat scenarios and from 55 to 57% in electricity scenarios. Pelletizing stages present similar impacts with a contribution between 28 and 30% in the heat production and between 26 and 27% for electricity production. The transport stage and emissions associated with combustion for domestic heat and district heating are also quite similar, close to 6%, and considering the electricity power plant scenario, the contribution varies between 5 and 6%.. GHG emissions savings vary from 60-62 % in the case of heating generation, being lower (36-39%) for the electricity value chain. Aligned with the environmental analysis, from the external costs perspective, the cardoon for heating application has potential benefits. However, the impact due to PM2,5 emissions must be considered a relevant disadvantage and measures of control should be developed., Proceedings of the 29th European Biomass Conference and Exhibition, 26-29 April 2021, Online, pp. 1100-1106 more...

This investigation concerns the ways in which young children (ages 5 to 8) compare quantities and how they work out the difference between them. The experiments involved children's understanding of mathematical problems and their ability to make use of graphical information in such problems. Each child was shown a series of illustrations, each representing two sets of quantities where the numerical difference was represented either discontinuously or continuously. The children were asked Equalize and Compare questions about each illustration and had to choose the correct answer from the set which represented the choice stimuli. Children's use of strategies was observed. In Experiment 1 (5-to-8-year-olds), only the younger children (5-to-6-year-olds) were observed to perform much more accurately on the Equalize-type question than on the Compare in both discontinuous and continuous conditions. The 7-to-8-year-olds reached a ceiling effect in performance, suggesting that by this age they can already deal with different types of arithmetic problems and with different types of graphical information. Experiment 2 (5-to-6-year-olds) repeated the first experiment presenting the graphical information on a microcomputer, but the discontinuous and continuous conditions were subdivided on the basis of the use of the comparative term "more" or "less". Children are helped significantly by the use of discontinuous material and by the use of "more" in Equalize-type questions only. These results did not support those of Experiment 1 where the Equalize and Compare difference was significant with both discontinuous and continuous material. Experiment 3 introduced part-whole manipulations in order to find out why Compare questions are more difficult to solve than Equalize questions. Five-to-6-year-olds' performance on Compare word problems was not affected by this type of manipulation. Experiment 4 explored the Equalize and Compare difference by presenting the material in a story-telling context. Again, the 5-to-6-year-olds' performance on Compare word problems was not affected by this type of manipulation. However, Equalize questions were helped by the use of the comparative term "more", as in Experiments 2 and 3, and by the presentation of discontinuous material, as in Experiment 2. Experiments 5 and 6 explored children's (5-to-8-year-olds) performance on Equalize- and Compare-type questions using spatial imagery manipulations. Experiment 5 involved manipulations of display in order to examine children's relative ease with Equalize word problems. Again, children's performance was not affected by this type of manipulation. In addition to the display manipulations, Experiment 6 introduced different level manipulations. However, in this experiment, the comparative pair was not represented in the choice stimuli. Children's performance on Compare word problems improved. There was no sign of the Equalize and Compare distinction which may be due to the fact that there was no representation of the comparative pair. The results show that the Equalize and Compare difference is due to a combination of their inherent structural and linguistic factors. Furthermore, the difficulty children have with Compare word problems is non-number-specific, but their relative ease with Equalize word problems is number-specific. Such type results indicate that children represent these two problems very differently. more...

Water scarcity is a major problem in the Mediterranean basin. Spain is one of the most arid countries in the European Union; therefore growing energy crops as Sorghum bicolor will be only possible if enough water is available at reasonable economic and environmental cost. Water extraction from groundwater or surface water bodies, along with the application of pressure needed for irrigation, suppose great energy consumption and an increasing cost for crops. Irrigation agriculture is intensive in electricity consumption. Spain has undertaken a major modernization of irrigation in recent decades. Gravity irrigation, prevailing for years, has been replaced by sprinkler or drip irrigation. This transformation toward more modern and efficient irrigation however has been accompanied by a sharp increase in electricity consumption, thereby increasing the environmental impact associated to the agricultural sector. Irrigation increases greenhouse gases (GHG) footprint from energy crops, adding environmental burdens to common agriculture stages. Use of renewable energies to provide water, as solar photovoltaic (PV) energy, would contribute to reduce GHG emissions and fossil energy consumption, while improving environmental behavior of energy crops. This paper explores the GHG emission and energy savings when solar energy is introduced in agriculture to provide irrigation needs in energy crops., Proceedings of the 24th European Biomass Conference and Exhibition, 6-9 June 2016, Amsterdam, The Netherlands, pp. 1479-1484 more...

The Renewable Energy Directive (RED) [1] and Fuel Quality Directive (FQD) [2] set the sustainability criteria for biofuels to be consumed in Europe. Following these criteria, biofuels have to reduce their greenhouse gas (GHG) emissions by at least 35% (and 50% from 2017 and 60% from 2018) in comparison with the estimated fossil fuels reference emissions by the European Directive (83.8 gCO2equiv/MJ). LCA calculations on GHG emissions from energy crops have been usually carried out considering common agricultural practices. This paper explores the amount of GHG emissions which could be saved by introducing conservation agriculture. No till and reduced tillage emission savings have been calculated in comparison with full tillage crop management. These improvements in agricultural management, are still a minority in the country, but gradually increase year by year, by environmental awareness to prevent soil erosion, increase biodiversity, provide higher water storage capacity, rise organic matter on topsoil, etc., Proceedings of the 23rd European Biomass Conference and Exhibition, 1-4 June 2015, Vienna, Austria, pp. 1536-1542 more...