Diagnóstico socioecológico y tipificación de agricultura familiar periurbana, con énfasis en producción de durazno (Prunus persica), en El Jarillo, Venezuela

The objective of this work was to typify and describe, from a socioecological perspective, the agricultural activity of the family farming systems in El Jarillo, Venezuela. A transversal descriptive research was carried out from 2009 to 2016 and mixed methods and tools were used, including ethnographic ones. Twenty-seven family farming systems and 44 indicators were measured and analyzed to describe the main characteristics of the systems. Emphasis was placed on peach production. The indicators were grouped in four categories of analysis: Quality of Life (QL), Social Reproduction of the Family (SRF), Energy Efficiency and Conservation of Natural Resources (EECNR) and Autonomy vis-à-vis the Markets (AM). All indicator were weighted on a scale of 0 to 4. Despite being all systems focused on peach production, the differences were sufficient to identify the four types of production systems (A-D). Most of the farms grouped in type A (68%), and only one farm in type D (4%). Types A and D produce only peach, types B produce peach combined with other crops for sale and types C produce items for self-consumption. The average yield of peach was higher than 140 kg plant-1 crop-1 in the period analyzed for all types, except for type D. All types of farms are using agrochemicals to fertilize, fight pests and diseases, and induce flowering, based on techniques of the green revolution. The categories of QL, SRF and AM turned out to be favorable to sustainability, however, the difficulties encountered in the EECNR limit sustainability. The quality of life standards of the farming families are the product of the high rentability and the moderate economic risk, at the expense of the natural resourcesPostprint (published version

Socioecological diagnosis and peri-urban family agriculture typification, with emphasis in the production of peach (Prunus persica), in El Jarillo, Venezuela

The objective of this work was to typify and describe, from a socioecological perspective, the agricultural activity of the family farming systems in El Jarillo, Venezuela. A transversal descriptive research was carried out from 2009 to 2016 and mixed methods and tools were used, including ethnographic ones. Twenty-seven family farming systems and 44 indicators were measured and analyzed to describe the main characteristics of the systems. Emphasis was placed on peach production. The indicators were grouped in four categories of analysis: Quality of Life (QL), Social Reproduction of the Family (SRF), Energy Efficiency and Conservation of Natural Resources (EECNR) and Autonomy vis-à-vis the Markets (AM). All indicator were weighted on a scale of 0 to 4. Despite being all systems focused on peach production, the differences were sufficient to identify the four types of production systems (A-D). Most of the farms grouped in type A (68%), and only one farm in type D (4%). Types A and D produce only peach, types B produce peach combined with other crops for sale and types C produce items for self-consumption. The average yield of peach was higher than 140 kg plant-1 crop-1 in the period analyzed for all types, except for type D. All types of farms are using agrochemicals to fertilize, fight pests and diseases, and induce flowering, based on techniques of the green revolution. The categories of QL, SRF and AM turned out to be favorable to sustainability, however, the difficulties encountered in the EECNR limit sustainability. The quality of life standards of the farming families are the product of the high rentability and the moderate economic risk, at the expense of the natural resources.The objective of this work was to typify and describe, from a socioecological perspective, the agricultural activity of the family farming systems in El Jarillo, Venezuela. A transversal descriptive research was carried out from 2009 to 2016 and mixed methods and tools were used, including ethnographic ones. Twenty-seven family farming systems and 44 indicators were measured and analyzed to describe the main characteristics of the systems. Emphasis was placed on peach production. The indicators were grouped in four categories of analysis: Quality of Life (QL), Social Reproduction of the Family (SRF), Energy Efficiency and Conservation of Natural Resources (EECNR) and Autonomy vis-à-vis the Markets (AM). All indicator were weighted on a scale of 0 to 4. Despite being all systems focused on peach production, the differences were sufficient to identify the four types of production systems (A-D). Most of the farms grouped in type A (68%), and only one farm in type D (4%). Types A and D produce only peach, types B produce peach combined with other crops for sale and types C produce items for self-consumption. The average yield of peach was higher than 140 kg plant-1 crop-1 in the period analyzed for all types, except for type D. All types of farms are using agrochemicals to fertilize, fight pests and diseases, and induce flowering, based on techniques of the green revolution. The categories of QL, SRF and AM turned out to be favorable to sustainability, however, the difficulties encountered in the EECNR limit sustainability. The quality of life standards of the farming families are the product of the high rentability and the moderate economic risk, at the expense of the natural resources

PV Energy Performance in a Sustainable Campus

Producción CientíficaThe challenge of photovoltaic integration as the basis of an energy generation system has been achieved and carried out by the University Autónoma de Cali, Colombia, using an avant-garde energy technology model. This innovative sustainable campus not only fulfills its purpose as an advanced model of a renewable energy integration system, it also aims at environmental research, e-mobility, and energy efficiency. This paper describes how the university implements the technological innovation of integrating the photovoltaic system installation in a university campus, showing its relevant contribution to the electricity generation in the campus buildings by analyzing the different electrical parameters together with the system performance indicators. The implementation of technological solutions has allowed the generation of a quantity of renewable energy within the campus, supplying a sustainable energy response based on energy efficiency and carbon emissions savings. This innovation has been applied following the international standards for the evaluation of the energy performance of photovoltaic systems (IEC 61724), reaching very optimal values for this type of renewable solution. In this paper, the dynamic monitoring of several parameters has been carried out in order to analyze the energy performance, and an energy simulation has been used to achieve optimal solutions and to obtain the perfect modeling of the system. This study shows how to evaluate the performance of an integration of a photovoltaic system in a smart university campus, according to international standards. It achieves complete viability due to its economic savings, energy efficiency and reduction of carbon emission

PV energy performance in a sustainable campus

The challenge of photovoltaic integration as the basis of an energy generation system has been achieved and carried out by the University Autónoma de Cali, Colombia, using an avant-garde energy technology model. This innovative sustainable campus not only fulfills its purpose as an advanced model of a renewable energy integration system, it also aims at environmental research, e-mobility, and energy efficiency. This paper describes how the university implements the technological innovation of integrating the photovoltaic system installation in a university campus, showing its relevant contribution to the electricity generation in the campus buildings by analyzing the different electrical parameters together with the system performance indicators. The implementation of technological solutions has allowed the generation of a quantity of renewable energy within the campus, supplying a sustainable energy response based on energy efficiency and carbon emissions savings. This innovation has been applied following the international standards for the evaluation of the energy performance of photovoltaic systems (IEC 61724), reaching very optimal values for this type of renewable solution. In this paper, the dynamic monitoring of several parameters has been carried out in order to analyze the energy performance, and an energy simulation has been used to achieve optimal solutions and to obtain the perfect modeling of the system. This study shows how to evaluate the performance of an integration of a photovoltaic system in a smart university campus, according to international standards. It achieves complete viability due to its economic savings, energy efficiency and reduction of carbon emissio

Return period curves for extreme 5-min rainfall amounts at the Barcelona urban network

Heavy rainfall episodes are relatively common in the conurbation of Barcelona and neighbouring cities (NE Spain), usually due to storms generated by convective phenomena in summer and eastern and south-eastern advections in autumn. Prevention of local flood episodes and right design of urban drainage have to take into account the rainfall intensity spread instead of a simple evaluation of daily rainfall amounts. The database comes from 5-min rain amounts recorded by tipping buckets in the Barcelona urban network along the years 1994–2009. From these data, extreme 5-min rain amounts are selected applying the peaks-over-threshold method for thresholds derived from both 95% percentile and the mean excess plot. The return period curves are derived from their statistical distribution for every gauge, describing with detail expected extreme 5-min rain amounts across the urban network. These curves are compared with those derived from annual extreme time series. In this way, areas in Barcelona submitted to different levels of flood risk from the point of view of rainfall intensity are detected. Additionally, global time trends on extreme 5-min rain amounts are quantified for the whole network and found as not statistically significant.Peer ReviewedPostprint (author's final draft

Towards concepts for climate and energy-oriented digital twins for buildings

Este artículo presenta conceptos y enfoques para crear un gemelo digital orientado al clima y la energía para edificios públicos. El funcionamiento sostenible y eficiente de los recursos de estos edificios, como escuelas y centros educativos, y la monitorización, control y optimización de su clima, aire y rendimiento energético plantean múltiples retos, en particular para hacer frente a las consecuencias del cambio climático y a los cambios en la economía energética. En nuestro planteamiento, consideramos edificios en los que una red de sensores heterogéneos en cada unidad espacial registra propiedades clave como la temperatura, la humedad y la concentración de CO2, así como el consumo de energía y la producción de energía solar. Los datos recogidos continuamente por los sensores forman un espacio de datos espaciotemporal, que el gemelo digital utiliza como base para análisis y simulaciones basados en IA. La transferencia de datos de series temporales en tiempo casi real puede realizarse mediante diferentes bases de datos. Las técnicas de análisis centradas en los datos de series temporales permiten un acceso selectivo a la información y ayudan a identificar acontecimientos excepcionales, patrones recurrentes y la comparación de resultados relacionados con la energía y el clima. Actualmente se está implantando un prototipo de gemelo digital orientado a la energía y el clima en un proyecto gubernamental en Andalucía, España, que abarca unos 430 edificios públicos

A Conscious, Smart Site Model for a Solar-Water Energy System

Este trabajo propone un modelo global de desalinización sostenible en el contexto hidrológico de cualquier río con embalse cercano al mar. Para ello, se instala una planta desaladora, situada en la costa, que transporta el agua bombeada utilizando el propio curso del río y la vierte directamente al embalse. El concepto de sostenibilidad radica en que la energía necesaria para abastecer todo el proceso se obtiene mediante un parque fotovoltaico flotante ubicado en el embalse. La energía eléctrica generada por este parque proporciona una solución de autoconsumo tanto para la planta desaladora como para las estaciones de bombeo, ya sea inyectando y equilibrando su energía a la red eléctrica o directamente a la planta desaladora. Además, como producto destacable en el proceso de desalinización, se obtienen diversos derivados y el proyecto se convierte en una fuente de hidrógeno verd

Rainfall disparity at monthly scale on Catalonia (NE Spain): dependence on geographic coordinates, altitude and distance to the Mediterranean coast

The rainfall regime in Catalonia, NE Spain, has a typical Mediterranean behaviour with irregular monthly amounts, sometimes the result of copious and intense torrential episodes for a few months, while for others precipitation is scarce. In addition, the varied topography of this region is related to significant rainfall differences between its different areas. The monthly precipitation from 97 stations spread throughout the territory, from 1950 to 2016, has allowed a detailed study of the spatial distribution of rainfall irregularity, based on the concept of disparity, D. The disparities have been calculated for every calendar month, to characterise the rainfall amount inter-annual oscillations, and also for all the consecutive months, to evaluate the rainfall disparity along the year. The spatial distribution of D has been obtained for all cases, showing a main general increase from North to South, and a secondary increase from West to East, in some months such as July. The winter months, especially January, have the highest values of D, which can reach the value of 2.0. The dependence of D on altitude and distance from the coast has also been analysed. The correlation is predominantly negative in both cases, although in some months, such as January, this correlation is not so clear. Additionally, the histograms of D show statistical characteristics, such as signs of a Gaussian distribution for some calendar months, as well as clear asymmetry in others. The obtained results could be interesting to detect the calendar months with the highest uncertainty on their expected rain amounts, contributing to a better knowledge of the complex structure of the rainfall Mediterranean regime.Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature. This research was supported by the Spanish Ministry of Science, Innovation and Universities (grant PID2019-105976RB-I00 and grant AGL2017-87658-R).Postprint (published version

Multifractal structure of the monthly rainfall regime in Catalonia (NE Spain): Evaluation of the non-linear structural complexity

The complex non-linear regime of the monthly rainfall in Catalonia (NE Spain) is analyzed by means of the reconstruction fractal theorem and the multifractal detrended fluctuation analysis algorithm. Areas with a notable degree of complex physical mechanisms are detected by using the concepts of persistence (Hurst exponent), complexity (embedding dimension), predictive uncertainty (Lyapunov exponents), loss of memory of the mechanism (Kolmogorov exponent), and the set of multifractal parameters (Hölder exponents, spectral asymmetry, spectral width, and complexity index). Besides these analyses permitting a detailed description of monthly rainfall pattern characteristics, the obtained results should also be relevant for new research studies concerning monthly amounts forecasting at a monthly scale. On one hand, the number of necessary monthly data for autoregressive processes could change with the complexity of the multifractal structure of the monthly rainfall regime. On the other hand, the discrepancies between real monthly amounts and those generated by some autoregressive algorithms could be related to some parameters of the reconstruction fractal theorem, such as the Lyapunov and Kolmogorov exponents. The monthly rainfall regime in Catalonia, NE Spain, is analyzed by means of the fractal theory with the aim of improving the knowledge about its complex physical mechanism.Peer ReviewedPostprint (author's final draft

Ultrasound-guided umbilical venous catheterisation: A cost-effectiveness analysis

Introduction: Although the use of ultrasound for the insertion of central catheters has proven to be cost-effective in adults, it is not known if this is the case in the neonatal population. This study compared the cost-effectiveness of ultrasound-guided umbilical venous catheterisation with conventional catheterisation in a neonatal intensive care unit of a Public University Hospital. Patients and methods: A retrospective observational study was conducted on newborns that required an umbilical venous catheter before completing their first 24 h of extra-uterine life. Two retrospective cohorts were formed, including one with ultrasound-guided catheterisation and the other with conventional catheterisation. The effectiveness was measured using 2 variables: placement of ideal position and insertion without complications. The cost of human and material resources (consumable and non-consumable), the cost-effectiveness ratio, and the incremental cost-effectiveness ratio were estimated, as well as carrying out a sensitivity analysis. Results: Catheter obstruction was more frequent in guided catheterisation than in conventional catheterisation (7.7% vs. 0%, P = .04) and catheter dysfunction was higher in the latter (79% vs. 3.8%, P < .0001). The cost-effectiveness ratio of the guided catheterisation wa