15 research outputs found

    The value of satellite remote sensing soil moisture data and the DISPATCH algorithm in irrigation fields

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    Soil moisture measurements are needed in a large number of applications such as hydro-climate approaches, watershed water balance management and irrigation scheduling. Nowadays, different kinds of methodologies exist for measuring soil moisture. Direct methods based on gravimetric sampling or time domain reflectometry (TDR) techniques measure soil moisture in a small volume of soil at few particular locations. This typically gives a poor description of the spatial distribution of soil moisture in relatively large agriculture fields. Remote sensing of soil moisture provides widespread coverage and can overcome this problem but suffers from other problems stemming from its low spatial resolution. In this context, the DISaggregation based on Physical And Theoretical scale CHange (DISPATCH) algorithm has been proposed in the literature to downscale soil moisture satellite data from 40 to 1¿km resolution by combining the low-resolution Soil Moisture Ocean Salinity (SMOS) satellite soil moisture data with the high-resolution Normalized Difference Vegetation Index (NDVI) and land surface temperature (LST) datasets obtained from a Moderate Resolution Imaging Spectroradiometer (MODIS) sensor. In this work, DISPATCH estimations are compared with soil moisture sensors and gravimetric measurements to validate the DISPATCH algorithm in an agricultural field during two different hydrologic scenarios: wet conditions driven by rainfall events and wet conditions driven by local sprinkler irrigation. Results show that the DISPATCH algorithm provides appropriate soil moisture estimates during general rainfall events but not when sprinkler irrigation generates occasional heterogeneity. In order to explain these differences, we have examined the spatial variability scales of NDVI and LST data, which are the input variables involved in the downscaling process. Sample variograms show that the spatial scales associated with the NDVI and LST properties are too large to represent the variations of the average soil moisture at the site, and this could be a reason why the DISPATCH algorithm does not work properly in this field site.Peer ReviewedPostprint (published version

    Evaluación de las medidas de humedad de suelo generadas con datos disgregados de satélite a escala de parcela agrícola

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    El interés de medir la humedad de suelo a escala de parcela de cultivo mediante teledetección ha aumentado debido a la fácil disponibilidad de los datos y, que a diferencia de los sensores de humedad de suelo, no es necesario dedicar tiempo y dinero a la instalación y mantenimiento en campo. Estas medidas tienen una baja resolución espacial de 40 km. El algoritmo DisPATCh disgrega los valores de humedad de suelo de 40 km a 1 km de resolución. En este trabajo se han comparado medidas de humedad in situ de la parcela con los valores obtenidos con el algoritmo DisPATCh para evaluar en qué escenarios puede estimar correctamente la humedad de suelo a 1 km de resolución. También se ha realizado un estudio geoestadístico mediante variogramas para comprobar que DisPATCh estima la humedad de suelo a la resolución comentada. Los resultados muestran que DisPATCh no es capaz de estimar la humedad de suelo cuando las condiciones de humedad del área de estudio son distintas a las de la región donde se encuentra.Postprint (published version

    Combined simulation and optimization framework for irrigation scheduling in agriculture fields

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    In the context of growing evidence of climate change and the fact that agriculture uses about 70% of all the water available for irrigation in semi-arid areas, there is an increasing probability of water scarcity scenarios. Water irrigation optimization is, therefore, one of the main goals of researchers and stakeholders involved in irrigated agriculture. Irrigation scheduling is often conducted based on simple water requirement calculations without accounting for the strong link between water movement in the root zone, soil–water–crop productivity and irrigation expenses. In this work, we present a combined simulation and optimization framework aimed at estimating irrigation parameters that maximize the crop net margin. The simulation component couples the movement of water in a variably saturated porous media driven by irrigation with crop water uptake and crop yields. The optimization component assures maximum gain with minimum cost of crop production during a growing season. An application of the method demonstrates that an optimal solution exists and substantially differs from traditional methods. In contrast to traditional methods, results show that the optimal irrigation scheduling solution prevents water logging and provides a more constant value of water content during the entire growing season within the root zone. As a result, in this case, the crop net margin cost exhibits a substantial increase with respect to the traditional method. The optimal irrigation scheduling solution is also shown to strongly depend on the particular soil hydraulic properties of the given field site.We thank to our colleagues from Aigües Segarra Garrigues (ASG) company for sharing some of the data necessary to conduct this work and also to Doctorats Industrials to fund the project where this work is involved.Peer ReviewedPostprint (published version

    Dynamic management zones for irrigation scheduling

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    Irrigation scheduling decision-support tools can improve water use efficiency by matching irrigation recommendations to prevailing soil and crop conditions within a season. Yet, little research is available on how to support real-time precision irrigation that varies within-season in both time and space. We investigate the integration of remotely sensed NDVI time-series, soil moisture sensor measurements, and root zone simulation forecasts for in-season delineation of dynamic management zones (MZ) and for a variable rate irrigation scheduling in order to improve irrigation scheduling and crop performance. Delineation of MZ was conducted in a 5.8-ha maize field during 2018 using Sentinel-2 NDVI time-series and an unsupervised classification. The number and spatial extent of MZs changed through the growing season. A network of soil moisture sensors was used to interpret spatiotemporal changes of the NDVI. Soil water content was a significant contributor to changes in crop vigor across MZs through the growing season. Real-time cluster validity function analysis provided in-season evaluation of the MZ design. For example, the total within-MZ daily soil moisture relative variance decreased from 85% (early vegetative stages) to below 25% (late reproductive stages). Finally, using the Hydrus-1D model, a workflow for in-season optimization of irrigation scheduling and water delivery management was tested. Data simulations indicated that crop transpiration could be optimized while reducing water applications between 11 and 28.5% across the dynamic MZs. The proposed integration of spatiotemporal crop and soil moisture data can be used to support management decisions to effectively control outputs of crop × environment × management interactions.Mention of trade names or commercial products in this publication is solely for the purpose of providing specific information and does not imply recommendation or endorsement by the U.S. Department of Agriculture. This study was supported by the European Commission Horizon 2020 Programme for Research and Innovation (H2020) in the context of the Marie Sklodowska-Curie Research and Innovation Staff Exchange (RISE) action (ACCWA project, grant agreement no.: 823965). This study was also funded by the project ‘Low Input Sustainable Agriculture (LISA)’ under the Operational program FEDER for Catalonia 2014‐2020 RIS3CAT (http://www.lisaproject.cat/introduction/).Peer ReviewedPostprint (author's final draft

    Espai de millora contínua dels plans locals de prevenció de drogues 2018. Orientacions aplicades per a la millora dels plans municipals de drogues

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    El present document és el resultat final de 'l'espai de millora contínua dels plans locals de prevenció de drogues 1', un espai de formació gestionat per la Subsecció de Projectes i Programes del Servei de Suport de Programes Socials de l'Àrea d'Atenció a les Persones de la Diputació de Barcelona i executat per la Unitat de Polítiques de Drogues de la Facultat de Psicologia de la Universitat Autònoma de Barcelona. La finalitat d'aquest espai és proveir d'eines tant conceptuals com pràctiques a les i els professionals responsables d'un pla municipal o supramunicipal de drogues de la demarcació de Barcelona, per a millorar l'execució, l'aplicació, la qualitat, l'eficàcia i l'eficiència de tota activitat preventiva aplicada en l'àmbit municipa

    Cohort Study Methodology of the ITINERE Project on Heroin Users in Three Spanish Cities and Main Characteristics of the Participants

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    Fundamento: Los estudios de cohortes permiten monitorizar el impacto del uso de drogas sobre la salud, e identificar los factores condicionantes. El objetivo de este trabajo es describir la metodología y las características básicas de una cohorte de consumidores de heroína diseñada con este fin. Métodos: Participaron 991 jóvenes consumidores de heroína, seleccionados en la comunidad en Barcelona, Madrid y Sevilla, principalmente mediante nominación de otros participantes (39,7%) o de consumidores o exconsumidores no participantes (44,7%). Se administró un cuestionario con ordenador y se recogió una muestra de sangre en papel secante. También se registraron sus medidas antropométricas. Se remuneró a participantes y captadores. Se usaron métodos estadísticos uni y bivariados. Resultados: Un 42,4% había cambiado alguna vez de vía principal de administración de heroína, sobre todo hacia la inyección en Barcelona y hacia la vía pulmonar en Sevilla. Un 75,8% (Barcelona), 49,8% (Madrid), y 15,5% (Sevilla) se habían inyectado drogas en los últimos 12 meses. En Madrid y Sevilla un 96%-97% consumían la heroína sólo en forma de base, y en Barcelona predominaba la heroína-clorhidrato. Frecuentemente mezclaban heroína y cocaína en la misma dosis (generalmente cocaína-base en Madrid y Sevilla, y cocaína-clorhidrato en Barcelona). Conclusiones: Persisten importantes diferencias geográficas en la prevalencia de inyección de drogas y en los patrones de consumo de heroína y cocaína, lo que podría explicar la desigual distribución de algunos problemas de salud. Las dificultades para reunir la muestra prevista sugieren un descenso importante de la incidencia de consumo de heroína.La fuente principal de financiación del estudio fue la Fundación para Investigación y la Prevención del Sida en España, a través del proyecto FIPSE 3035/99. También se han recibido apoyos para investigaciones específicas de: Redes Temáticas de Investigación Cooperativa (C03-09 y G03-005), Fondo de Investigación Sanitaria (FIS 00/1017, FIS 01/0908), y Delegación del Gobierno para el Plan Nacional sobre Drogas.S

    Algorismes eficients de deep learning per a aplicacions de seguretat en micromobilitat

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    In this project, a front-facing camera or mobile device installed on the micromobility vehicle captures video and recognizes the type of road (cycling lane, sidewalk, crosswalk, car road, etc.). This is necessary to give information to the user if it?s possible or not to circulate and the maximum speed that is allowed. Furthermore, deep learning algorithms in mobile devices have to be able to run in real time. Therefore we need to design efficient algorithms in order to reduce computational time, while reducing the least as possible the performance. This project is part oThis project consists of the implementation of efficient Deep Learning algorithms in order to increase safety in urban micromobility. It analyses software that is capable of identifying the type of road on which a light vehicle circulates and that has to be able to be executed on mobile devices in real time. To do this, this work has been divided into two parts: first, a set of urban videos, recorded from light vehicles during 2021 and 2022 in the city of Barcelona, have been used to build structured databases containing metadata extracted from the videos and other additional fields such as geolocation, the part of the day in which they were recorded or meteorological information. A representation system (inter- active map) has been created to visualise the routes travelled. In the second part of this thesis, the validation and testing of three different 2D Deep Learning models has been carried out: ShuffleNet v2 with 2021 database, ShuffleNet v2 with 2022 database and MobileNet v3 with 2022 database. The different tests have been designed to determine ways to lighten the program execution (higher efficiency) without losing accuracy in road type detection, con- cluding that ShuffleNet v2 with the 2022 database is the best option in predicting road type and minimising false positives.Este proyecto consiste en la implementación de algoritmos eficientes de Deep Learning a fin de aumentar la seguridad en la micromovilidad urbana. Se analiza un software que es capaz de identificar el tipo de vía por la que circula un vehícu- lo ligero y que ha de poder ser ejecutado en dispositivos móviles en tiempo real. Para ello, este trabajo se ha dividido en dos partes: primero se ha trabajado con un conjunto de vídeos urbanos, grabados desde vehículos ligeros durante 2021 y 2022 en la ciudad de Barcelona y, a partir de ellos, se han construido bases de datos estructuradas que contienen metadatos extraídos de los vídeos y otros campos adicionales como la geolocalización, la parte del día en que fueron gra- bados o la información meteorológica. Se ha construido un sistema de represen- tación (mapa interactivo) que permite visualizar las rutas seguidas. En la segunda parte de este trabajo se ha realizado la validación y comprobación de tres modelos 2D de Deep Learning diferentes: ShuffleNet v2 con base de da- tos 2021, ShuffleNet v2 con base de datos 2022 y MobileNet v3 con base de da- tos 2022. Las diferentes pruebas han sido diseñadas para determinar formas de aligerar la ejecución del programa (mayor eficiencia) sin perder precisión en la detección del tipo de vía, concluyendo que ShuffleNet v2 con la base de datos de 2022 es la mejor opción prediciendo el tipo de vía y minimizando falsos positivos.Aquest projecte consisteix en la implementació d'algorismes eficients de Deep Learning a fi d?augmentar la seguretat en la micromobilitat urbana. S'a- nalitza un programari que és capaç d'identificar el tipus de via per la qual circula un vehicle lleuger i que ha de poder ser executat en dispositius mòbils en temps real. Per a això, aquest treball s'ha dividit en dues parts: primer s'ha treballat amb un conjunt de vídeos urbans, gravats des de vehicles lleugers durant 2021 i 2022 a la ciutat de Barcelona i, a partir d'ells, s'han construït bases de dades estructura- des que contenen metadades extretes dels vídeos i altres camps addicionals com la geolocalització, la part del dia en què van ser gravats o la informació meteoro- lògica. S'ha construït un sistema de representació (mapa interactiu) que permet visualitzar les rutes seguides. En la segona part d'aquest treball s'ha realitzat la validació i comprovació de tres models 2D de Deep Learning diferents: ShuffleNet v2 amb base de dades 2021, ShuffleNet v2 amb base de dades 2022 i MobileNet v3 amb base de dades 2022. Les diferents proves han estat dissenyades per a determinar maneres d'alleugerir l'execució del programa (major eficiència) sense perdre precisió en la detecció del tipus de via, concloent que ShuffleNet v2 amb la base de dades de 2022 és la mi- llor opció predient el tipus de via i minimitzant falsos positius

    Evaluación de las medidas de humedad de suelo generadas con datos disgregados de satélite a escala de parcela agrícola

    No full text
    El interés de medir la humedad de suelo a escala de parcela de cultivo mediante teledetección ha aumentado debido a la fácil disponibilidad de los datos y, que a diferencia de los sensores de humedad de suelo, no es necesario dedicar tiempo y dinero a la instalación y mantenimiento en campo. Estas medidas tienen una baja resolución espacial de 40 km. El algoritmo DisPATCh disgrega los valores de humedad de suelo de 40 km a 1 km de resolución. En este trabajo se han comparado medidas de humedad in situ de la parcela con los valores obtenidos con el algoritmo DisPATCh para evaluar en qué escenarios puede estimar correctamente la humedad de suelo a 1 km de resolución. También se ha realizado un estudio geoestadístico mediante variogramas para comprobar que DisPATCh estima la humedad de suelo a la resolución comentada. Los resultados muestran que DisPATCh no es capaz de estimar la humedad de suelo cuando las condiciones de humedad del área de estudio son distintas a las de la región donde se encuentra

    The value of satellite remote sensing soil moisture data and the DISPATCH algorithm in irrigation fields

    No full text
    Soil moisture measurements are needed in a large number of applications such as hydro-climate approaches, watershed water balance management and irrigation scheduling. Nowadays, different kinds of methodologies exist for measuring soil moisture. Direct methods based on gravimetric sampling or time domain reflectometry (TDR) techniques measure soil moisture in a small volume of soil at few particular locations. This typically gives a poor description of the spatial distribution of soil moisture in relatively large agriculture fields. Remote sensing of soil moisture provides widespread coverage and can overcome this problem but suffers from other problems stemming from its low spatial resolution. In this context, the DISaggregation based on Physical And Theoretical scale CHange (DISPATCH) algorithm has been proposed in the literature to downscale soil moisture satellite data from 40 to 1¿km resolution by combining the low-resolution Soil Moisture Ocean Salinity (SMOS) satellite soil moisture data with the high-resolution Normalized Difference Vegetation Index (NDVI) and land surface temperature (LST) datasets obtained from a Moderate Resolution Imaging Spectroradiometer (MODIS) sensor. In this work, DISPATCH estimations are compared with soil moisture sensors and gravimetric measurements to validate the DISPATCH algorithm in an agricultural field during two different hydrologic scenarios: wet conditions driven by rainfall events and wet conditions driven by local sprinkler irrigation. Results show that the DISPATCH algorithm provides appropriate soil moisture estimates during general rainfall events but not when sprinkler irrigation generates occasional heterogeneity. In order to explain these differences, we have examined the spatial variability scales of NDVI and LST data, which are the input variables involved in the downscaling process. Sample variograms show that the spatial scales associated with the NDVI and LST properties are too large to represent the variations of the average soil moisture at the site, and this could be a reason why the DISPATCH algorithm does not work properly in this field site.Peer Reviewe
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