127 research outputs found

    Real-time energy optimization of irrigation scheduling by parallel multi-objective genetic algorithms

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    [EN] The present work is motivated by the need to reduce the energy costs arising from the pressure demands of drip and sprinkling irrigation, compounded by the increase in the energy price in recent years. Researchers have demonstrated that proper operation of the irrigation network reduces associated pumping costs. The main challenge was to obtain the optimal operation parameters on near real-time due to the fact that the high complexity of the optimization problem requires a great computational effort. The classic approach to the problem imposes a strict fulfilment of minimum pressures as a restriction. This study, however, presents a new methodology for the reordering of irrigation scheduling, incorporating the constraint of daily volume requests for each hydrant. The methodology is capable of minimizing the cost of energy while maximizing pressures at the critical hydrants. Cost reductions of about 6¿7% were reached for scenarios without pressure deficit for the case study. Greater computational efficiency was achieved by posing the problem from a multi-objective approach, on the one hand, and by establishing the parallel evaluation of the objective function, on the other. The speed-up obtained by combining a reduction in the number of function evaluations thanks to the faster convergence of the multi-objective approach and the reduction of the computational time due to the parallelization of the algorithm achieved results about 10 times faster. This improvement allowed the tool to be implemented for the daily optimization of irrigation requests.This work has been supported by the VALi+D R&D Program of the Generalitat Valenciana (Spain).Alonso-Campos, J.; Jiménez Bello, MA.; Martínez Alzamora, F. (2020). Real-time energy optimization of irrigation scheduling by parallel multi-objective genetic algorithms. Agricultural Water Management. 227:1-8. https://doi.org/10.1016/j.agwat.2019.105857S1822

    Assessment of a Remote Sensing Energy Balance Methodology (SEBAL) Using Different Interpolation Methods to Determine Evapotranspiration in a Citrus Orchard

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    "(c) 2015 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other users, including reprinting/ republishing this material for advertising or promotional purposes, creating new collective works for resale or redistribution to servers or lists, or reuse of any copyrighted components of this work in other works."A surface energy balance algorithm for land (SEBAL) for estimating evapotranspiration (ET) has been parameterized and tested in a 400-ha drip irrigated citrus orchard. Simultaneously, during three growing seasons, energy fluxes were measured using Eddy Covariance. Instantaneous fluxes obtained with SEBAL using 10 images from Landsat-5 were compared with the measured fluxes. The Perrier function was the best method for properly estimating the roughness momentum length for discontinuous canopies, as in citrus orchards. Crop height was estimated using LIDAR data. In general, SEBAL performed well for net radiation estimation but failed in soil heat flux estimation. Latent heat estimations from the SEBAL model had a relative root mean square error (rRMSE) of 0.06 when compared with measurements obtained by Eddy Covariance. Three procedures were tested for up-scaling the instantaneous ET estimates from SEBAL to daily ET values: 1) assuming the fraction between the actual ET and the reference ET is constant throughout the day; 2) using actual local crop coefficient curves; and 3) using an up-scaling factor where the fraction of hourly ET to daily ET equals the ratio of hourly to daily global solar radiation. This last method gave acceptable results for daily ET estimations (rRMSE = 0.09) and for 15day ET (rRMSE = 0.19), and its main advantage is that no local data are required. It is concluded that the SEBAL methodology can be successfully applied for determining actual ET, even in discontinuous citrus canopies. However, additional parameterizations of momentum roughness length were needed in order to obtain reliable ET determinations.This work was supported in part by MINECO project Rideco-Consolider CSD2006-0067 and in part by Interreg IV Sudoe project "Telerieg."Jiménez Bello, MÁ.; Castel, JR.; Testi, L.; Intrigliolo Molina, DS. (2015). Assessment of a Remote Sensing Energy Balance Methodology (SEBAL) Using Different Interpolation Methods to Determine Evapotranspiration in a Citrus Orchard. IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing. 8(4):1465-1477. https://doi.org/10.1109/JSTARS.2015.2418817S146514778

    Methodology for flushing pressurised irrigation networks for fertigation and operation maintenance purposes

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    [EN] Pressurised irrigation networks with a certain degree of automation allow centralized fertigation and maintenance operations such as cleaning subunits and preventing the proliferation of invasive species such as zebra mussels. Until now, there is no methodology that guarantees the total cleaning of the network of a substance in the shortest possible time. In the same way, it does not exist to guarantee reaching all consumption points with a certain concentration of a substance, injecting the minimum possible amount. For that purpose, a general novel methodology has been developed that makes use of the network¿s hydraulic model and parallel multi-objective genetic algorithms to flush the network of a certain substance or to get it to all consumption points in the shortest possible time and supplying a minimum volume. This method assumes that the available pressure at the source is always over a minimum value. The arrival times to the consumption points are minimized and the injected volume is reduced to the minimum of replacement, that is, the volume of the network pipes. The methodology applied to the study case allowed the entire network to be flushed in a minimum time of 2.46 h. On a normal irrigation day, without making any changes to the irrigation schedule the time to completely flush the network is 11.76 h. Furthermore, the injected volume differs greatly from the total volume of the pipes.This study has been partially supported by the ADAPTAMED project (RTI2018-101483-B-I00), funded by the Ministerio de Economia y Competitividad (MINECO) of Spain and with EU FEDER funds.Jiménez Bello, MA.; Alonso Campos, JC.; Manzano Juarez, J.; Martínez Alzamora, F. (2021). Methodology for flushing pressurised irrigation networks for fertigation and operation maintenance purposes. Irrigation Science. 39(3):375-384. https://doi.org/10.1007/s00271-021-00724-437538439

    Methodology for grouping intakes of pressurised irrigation networks into sectors to minimise energy consumption

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    [EN] Grouping intakes into sectors so they operate in scheduled periods allows irrigation networks to be operated more efficiently from an energy point of view. In the case of systems where water is supplied by pumps, the criteria used to date to create irrigation sectors does not guarantee that pumping sets work in the most efficient manner, despite the use of variable frequency drives. A new methodology, using a genetic algorithm and a hydraulic network model, has been developed to group intakes into sectors to minimise energy consumption. The methodology was applied to a case study and several scenarios compared using energy performance indicators. Predictions on a case study in Spain showed that energy savings of 36.4% could be possible and operational network conditions can be improved by ensuring minimum pressures are guaranteed.This work has been funded by IMPIVA of Comunidad Valenciana and the Spanish Ministry of Education and Science by means of the project CICYT BIA 2004-06444. The authors wish to thank the company TECVASA (Tecnicas Valencianas del Agua S.A.) for their collaboration in this study.Jiménez Bello, MÁ.; Martínez Alzamora, F.; Bou Soler, V.; Bartolín Ayala, HJ. (2010). Methodology for grouping intakes of pressurised irrigation networks into sectors to minimise energy consumption. Biosystems Engineering. 105(4):429-438. https://doi.org/10.1016/j.biosystemseng.2009.12.014S429438105

    A combined photophysical and computational study on the binding of mycophenolate mofetil and its major metabolite to transport proteins

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    [EN] Binding of the inmunodrepresive agent mycophenolate mofetil (MMP) and its pharmacologically active metabolite mycophenolic acid (MPA) to human serum albumin (HSA) and ¿1-acid glycoprotein (HAAG) has been investigated by an integrated approach involving selective excitation of the drug fluorophore, following their UV-A triggered fluorescence and docking studies. The formation of the protein/ligand complexes was evidenced by a dramatic enhancement of the fluorescence intensity and a hypsochromic shift of the emission band. In HSA, competitive studies using oleic acid as site I probe revealed site I as the main binding site of the ligands. Binding constants revealed that the affinity of the active metabolite by HSA is four-fold higher than its proactive form. Moreover, the affinity of MMP by HSA is three-fold higher than by HAAG. Docking studies revealed significant molecular binding differences in the binding of MMP and MPA to sub-domain IIA of HSA (site 1). For MPA, the aromatic moiety would be in close contact to Trp214 with the flexible chain pointing to the other end of the sub-domain; on the contrary, for MMP, the carboxylate group of the chain would be fixed nearby Trp214 through electrostatic interactions with residues Arg218 and Arg222.Financial support from the Spanish Ministry of Economy and Competiveness (CTQ2013-47872-C2-1-P, CTQ2016-78875-P, SAF2016-75638-R), the Xunta de Galicia (Centro singular de investigacion de Galicia accreditation 2016-2019, ED431G/09), the European Union (European Regional Development Fund-ERDF) and the Generalitat Valenciana (PROMETEO/2017/075) is gratefully acknowledgedVendrell-Criado, V.; González-Bello, C.; Miranda Alonso, MÁ.; Jiménez Molero, MC. (2018). A combined photophysical and computational study on the binding of mycophenolate mofetil and its major metabolite to transport proteins. Spectrochimica Acta Part A Molecular and Biomolecular Spectroscopy. 199:308-314. https://doi.org/10.1016/j.saa.2018.03.064S30831419

    Modulador acusto-óptico en amplitud de fibra óptica basado en ondas acústicas de flexión

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    Se reporta un estudio experimental de la operación de un modulador acusto-óptico (MAO) de fibra óptica basado en la interacción acusto-óptica producida por ondas acústicas de flexión estacionarias. Concentramos nuestra atención en los efectos de reducir el diámetro en la fibra óptica como mecanismo para optimizar la respuesta espectral del MAO. Como caso particular reportamos un modulador de 70 ¹m de diametro con una alta profundidad de modulación (60 %), bajas perdidas por inserción (1.3 dB) y un ancho ancho de banda a 3 dB de 40 nm que opera en el rango de los megahertz. Los resultados obtenidos demuestran que el incluir fibras estrechadas se puede considerar como un grado extra de libertad en el diseño del modulador para controlar el ancho de banda.An experimental study of an in-fiber acousto-optic modulator (AOM) based on the acousto-optic interaction produced by standing flexural acoustic waves is reported. We focus our attention in the effects of a gradual reduction in the optical fiber as the mechanisms to improve the spectral response of the AOM. As a particular case we report a 70-μm fiber AOM. Our approach permits the implementation of high modulation depth (60 %), low optical loss (1.3 dB) and a 3 dB broad modulation bandwidth of 40 nm, operating in the MHz frequency range. The experimental results demonstrate that including tapered optical fibers can be regarded as an extra degree of freedom to control the optical bandwidth of the modulator.Fil: Bello Jiménez, M. A.. Instituto de Investigacion en Comunicación Optica, Universidad Autónoma de San Luis Potosí; MéxicoFil: Cuadrado Laborde, Christian Ariel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Rosario. Instituto de Física de Rosario (i); ArgentinaFil: Diez, Antonio. Universidad de Valencia; EspañaFil: Cruz, Jose Luis. Universidad de Valencia; EspañaFil: Andres Bou, Miguel. Universidad de Valencia; Españ

    Evaluation of an operational real-time irrigation scheduling scheme for drip irrigated citrus fields in Picassent, Spain

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    [EN] Irrigated agriculture is very important for securing food production for an increasing population over the next decades. Given scarcity of water resources, optimal irrigation management is needed to reduce water while realizing maximal crop productivity. The new method of integrating soil water content measurements and the Community Land Model (CLM) using sequential data assimilation (DA) is promising to improve the prediction of soil water status and efficiently design irrigation strategies. Soil water content measured by FDR (Frequency Domain Reflectometry) was assimilated into CLM by LETKF (Local Ensemble Transform Kalman Filter) to improve model predictions. Atmospheric input data from GFS (Global Forecast System) were used to force CLM in order to predict short-term soil water contents. The irrigation amount was then calculated on the basis of the difference between predicted and targeted soil water content over the root zone. During the real-time irrigation campaigns in Picassent (Spain) in 2015 and 2016, there were 6 fields irrigated according the data assimilation-optimization approach (CLM-DA), 2 further fields according the FAO (Food and Agriculture Organization) water balance method and also 2 fields traditionally according the farmers preference. The required amount of irrigation water for each citrus field was applied by SCADA (supervisory control and data acquisition system). Compared with the traditionally irrigated fields by farmers, 24% less irrigation water was needed for the CLM-DA scheduled fields averaged over both years from July to September, while the FAO fields were irrigated with 22% less water. Stem water potential data and soil moisture recordings of the CLM-DA scheduled fields did not indicate significant water stress during the irrigation period. The CLM-DA scheduled fields received less irrigation water than traditionally irrigated fields, but the orange production was not significantly suppressed. Overall, our results show that the CLM-DA method is attractive given its water saving potential and automated approach, ease of incorporation of on-line measurements and ensemble based predictions of soil moisture evolution.The first author of this paper was funded by a stipend from the Government of China (CSC scholarship). The support of the super computing facilities of Forschungszentrum Juelich (JURECA) is gratefully acknowledged. We are also thankful to our colleagues in IVIA and Universitat Politecnica de Valencia for the installation of soil moisture sensors and conducting stem water potential measurements.Li, D.; Hendricks, H.; Han, X.; Jiménez Bello, MA.; Martínez Alzamora, F.; Vereeken, H. (2018). Evaluation of an operational real-time irrigation scheduling scheme for drip irrigated citrus fields in Picassent, Spain. Agricultural Water Management. 208:465-477. https://doi.org/10.1016/j.agwat.2018.06.022S46547720

    Unmixing-Based Fusion of Hyperspatial and Hyperspectral Airborne Imagery for Early Detection of Vegetation Stress

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    "© 2014 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.” Upon publication, authors are asked to include either a link to the abstract of the published article in IEEE Xplore®, or the article’s Digital Object Identifier (DOI).Many applications require a timely acquisition of high spatial and spectral resolution remote sensing data. This is often not achievable since spaceborne remote sensing instruments face a tradeoff between spatial and spectral resolution, while airborne sensors mounted on a manned aircraft are too expensive to acquire a high temporal resolution. This gap between information needs and data availability inspires research on using Remotely Piloted Aircraft Systems (RPAS) to capture the desired high spectral and spatial information, furthermore providing temporal flexibility. Present hyperspectral imagers on board lightweight RPAS are still rare, due to the operational complexity, sensor weight, and instability. This paper looks into the use of a hyperspectral-hyperspatial fusion technique for an improved biophysical parameter retrieval and physiological assessment in agricultural crops. First, a biophysical parameter extraction study is performed on a simulated citrus orchard. Subsequently, the unmixing-based fusion is applied on a real test case in commercial citrus orchards with discontinuous canopies, in which a more efficient and accurate estimation of water stress is achieved by fusing thermal hyperspatial and hyperspectral (APEX) imagery. Narrowband reflectance indices that have proven their effectiveness as previsual indicators of water stress, such as the Photochemical Reflectance Index (PRI), show a significant increase in tree water-stress detection when applied on the fused dataset compared to the original hyperspectral APEX dataset (R-2 = 0.62, p 0.1). Maximal R-2 values of 0.93 and 0.86 are obtained by a linear relationship between the vegetation index and the resp., water and chlorophyll, parameter content maps.This work was supported in part by the Belgian Science Policy Office in the frame of the Stereo II program (Hypermix project-SR/00/141), in part by the project Chameleon of the Flemish Agency for Innovation by Science and Technology (IWT), and in part by the Spanish Ministry of Science and Education (MEC) for the projects AGL2012-40053-C03-01 and CONSOLIDER RIDECO (CSD2006-67). The European Facility for Airborne Research EUFAR (www.eufar.net) funded the flight campaign (Transnational Access Project 'Hyper-Stress'). The work of D. S. Intrigliolo was supported by the Spanish Ministry of Economy and Competitiveness program "Ramon y Cajal."Delalieux, S.; Zarco-Tejada, PJ.; Tits, L.; Jiménez Bello, MÁ.; Intrigliolo Molina, DS.; Somers, B. (2014). Unmixing-Based Fusion of Hyperspatial and Hyperspectral Airborne Imagery for Early Detection of Vegetation Stress. IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing. 7(6):2571-2582. https://doi.org/10.1109/JSTARS.2014.2330352S257125827

    EVALUACIÓN Y PROPUESTAS DE MEJORA DEL USO DE LA ENERGÍA EN REDES DE RIEGO. APLICACIÓN A LA COMUNIDAD DE REGANTES MURADA NORTE (ORIHUELA, ALICANTE)

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    [ES] La modernización de las infraestructuras agrícolas de regadío ha supuesto generalmente un incremento en el consumo energético de estas instalaciones. Tomando como referencia el Protocolo de Auditoría Energética en Comunidad de Regantes (CCRR) del Instituto para la Diversificación y Ahorro de Energía (IDAE), se evalúan e identifican actuaciones de mejora del uso de la energía en la red de riego de la CCRR Murada Norte (Orihuela, Alicante). En primer lugar se caracteriza la red de riego, su gestión y su consumo, elaborando un modelo matemático de la red con herramientas SIG y EPANET. Posteriormente se realiza una evaluación del uso de la energía con los indicadores de gestión energética del protocolo del IDAE, a través del cual se consigue calificar energéticamente la CCRR. Finalmente como actuaciones de mejora se propone la construcción de una nueva balsa de regulación que permite reducir la altura media de impulsión, la sustitución del equipo de bombeo actual para mejorar la eficiencia del bombeo y reducir la potencia contratada en horas punta, y la renegociación de la tarifa eléctrica.Los autores de este trabajo muestran su agradecimiento a la CCRR Murada Norte por su participación en este estudio y al proyecto IMPADAPT (CGL2013-48424-C2-1-R) del Plan Estatal de I+D+i (Ministerio de Economía y Competitividad) por su financiación.Ruiz-Rodríguez, M.; Jiménez Bello, MÁ.; Pulido Velázquez, MA. (2015). EVALUACIÓN Y PROPUESTAS DE MEJORA DEL USO DE LA ENERGÍA EN REDES DE RIEGO. APLICACIÓN A LA COMUNIDAD DE REGANTES MURADA NORTE (ORIHUELA, ALICANTE). En XXXIII CONGRESO NACIONAL DE RIEGOS. Valencia 16-18 junio de 2015. Editorial Universitat Politècnica de València. https://doi.org/10.4995/CNRiegos.2015.1454OC

    Spatial-Temporal variability analysis of temperature in two viticulture sites in Spain and Slovenia

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    Objective of this research is to describe and compare the results of climate variables analyzed in two different viticulture sites; indeed, one study site is located in the Valencia wine region in Spain and the other is in the Goriška Brda region in Slovenia. The research includes the climate analysis for a period of five decades in both study sites, from 1965 to 2013, to follow temperature measured daily. In addition, the Huglin and Winkler indexes were calculated in the same research sites for the same time period. The analysis was conducted in four weather stations (two in Spanish site and two in Slovene site). The climate data analysis showed a considerable temporal variability with notable increase of temperatures; indeed, it showed also the significant spatial variability of climatic variables. The continent and sea influence created climate and spatial differences on the both study sites, which are comparable with the climate evolution in the study period. This preliminary work is encouraging and will be further developed. Moreover, the results of this paper will be used to elaborate a climate model for the 2015-2065 period in each site separately. The results of the climate comparison, will give us two different climate models, one for each study site, which will contribute to improve viticulture adaptation in the future.Sirnik, I.; Quenol, H.; Jiménez Bello, MA.; Manzano Juarez, J. (2015). Spatial-Temporal variability analysis of temperature in two viticulture sites in Spain and Slovenia. Agriculture and Forestry / Poljoprivreda i Sumarstvo. 66(4):221-230. doi:10.17707/AgricultForest.61.4.25S22123066
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