Now showing items 21-40 of 100

    • Characterisation of the LMS200 laser beam under the influence of blockage surfaces. Influence on 3D scanning of tree orchards 

      Sanz Cortiella, Ricardo; Llorens Calveras, Jordi; Rosell Polo, Joan Ramon; Gregorio López, Eduard; Palacín Roca, Jordi (Molecular Diversity Preservation International (MDPI), 2011)
      The geometric characterisation of tree orchards is a high-precision activity comprising the accurate measurement and knowledge of the geometry and structure of the trees. Different types of sensors can be used to perform ...
    • Ultrasonic and LIDAR sensors for electronic canopy characterization in vineyards: advances to improve pesticide application methods 

      Llorens Calveras, Jordi; Gil Moya, Emilio; Llop, Jordi; Escolà i Agustí, Alexandre (Molecular Diversity Preservation International (MDPI), 2011)
      Canopy characterization is a key factor to improve pesticide application methods in tree crops and vineyards. Development of quick, easy and efficient methods to determine the fundamental parameters used to characterize ...
    • Performance of an ultrasonic ranging sensor in apple tree canopies 

      Escolà i Agustí, Alexandre; Planas de Martí, Santiago; Rosell Polo, Joan Ramon; Pomar Gomà, Jesús; Camp, Ferran; Solanelles Batlle, Francesc; Gràcia, Felip; Llorens Calveras, Jordi; Gil Moya, Emilio (Molecular Diversity Preservation International (MDPI), 2011)
      Electronic canopy characterization is an important issue in tree crop management. Ultrasonic and optical sensors are the most used for this purpose. The objective of this work was to assess the performance of an ultrasonic ...
    • Analysis of vineyard differential management zones and relation to vine development, grape maturity and quality 

      Martínez Casasnovas, José Antonio; Agelet Fernández, J.; Arnó Satorra, Jaume; Ramos Martín, Ma. C. (Ma. Concepción) (Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (Espanya), 2012)
      The objective of research was to analyse the potential of Normalized Difference Vegetation Index (NDVI) maps from satellite images, yield maps and grapevine fertility and load variables to delineate zones with different ...
    • Spatial variability in grape yield and quality influenced by soil and crop nutrition characteristics 

      Arnó Satorra, Jaume; Rosell Polo, Joan Ramon; Blanco Ortiz, Ricardo; Ramos Martín, Ma. C. (Ma. Concepción); Martínez Casasnovas, José Antonio (Springer, 2012)
      Knowledge of spatial variability of soil fertility and plant nutrition is critical for planning and implementing site-specific vineyard management. To better understand the key drivers behind vineyard variability, yield ...
    • SIMLIDAR – Simulation of LIDAR performance in artificially simulated orchards 

      Méndez, Valeriano; Catalán, Heliodoro; Rosell Polo, Joan Ramon; Arnó Satorra, Jaume; Sanz Cortiella, Ricardo; Tarquis, Ana (Elsevier, 2012)
      SIMLIDAR is an application developed in C++ that generates an artificial orchard using a Lindenmayer system. The application simulates the lateral interaction between the artificial orchard and a laser scanner or LIDAR ...
    • Backscatter Error Bounds for the Elastic Lidar Two-Component Inversion Algorithm 

      Rocadenbosch Burillo, Francesc; Frasier, Stephen; Kumar, Dhiraj; Lange, Diego; Gregorio López, Eduard; Sicard, Michaël (Institute of Electrical and Electronics Engineers (IEEE), 2012)
      Total backscatter-coefficient inversion error bounds for the two-component lidar inversion algorithm (so-called Fernald's or Klett-Fernald-Sasano's method) are derived in analytical form in response to the following three ...
    • Parameter design of a biaxial lidar ceilometer 

      Gregorio López, Eduard; Rocadenbosch Burillo, Francesc; Tiana Alsina, Jordi; Comerón Tejero, Adolfo; Sanz Cortiella, Ricardo; Rosell Polo, Joan Ramon (Society of Photo-Optical Instrumentation Engineers, 2012)
      This paper presents parameter design methodology and related optomechanical engineering of a 905-nm diode-laser biaxial, eye-safe lidar ceilometer prototype for cloud-height monitoring. Starting with a brief review of the ...
    • A review of methods and applications of the geometric characterization of tree crops in agricultural activities 

      Rosell Polo, Joan Ramon; Sanz Cortiella, Ricardo (Elsevier, 2012)
      This paper presents the foundations and applications in agriculture of the main systems used for the geometrical characterization of tree plantations, including systems based on ultrasound, digital photographic techniques, ...
    • Variable rate sprayer. Part 1 – Orchard prototype: design, implementation and validation 

      Escolà i Agustí, Alexandre; Rosell Polo, Joan Ramon; Planas de Martí, Santiago; Gil Moya, Emilio; Pomar Gomà, Jesús; Camp, Ferran; Llorens Calveras, Jordi; Solanelles Batlle, Francesc (Elsevier, 2013)
      Discussions in recent decades about dosage models for applying plant protection products in orchards have failed to reach a compromise solution. Furthermore, canopies are spatially variable, and a uniform dose may not be ...
    • Variable rate sprayer. Part 2 – Vineyard prototype: design, implementation, and validation 

      Gil Moya, Emilio; Llorens Calveras, Jordi; Llop, Jordi; Fàbregas, X.; Escolà i Agustí, Alexandre; Rosell Polo, Joan Ramon (Elsevier, 2013)
      The structural characteristics of the canopy are a key consideration for improving the efficiency of the spray application process for tree crops. However, obtaining accurate data in an easy, practical, and efficient way ...
    • Relationship between tree row LIDAR-volume and leaf area density for fruit orchards and vineyards obtained with a LIDAR 3D Dynamic Measurement System 

      Sanz Cortiella, Ricardo; Rosell Polo, Joan Ramon; Llorens Calveras, Jordi; Gil Moya, Emilio; Planas de Martí, Santiago (Elsevier, 2013)
      In this work, a LIDAR 3D Dynamic Measurement System, based on a Two-Dimensional Terrestrial Laser-LIDAR Scanner (2D TLS), was used for the geometric characterisation of tree-row crops (apple trees, pear trees and vineyards). ...
    • LiDAR simulation in modelled orchards to optimise the use of terrestrial laser scanners and derived vegetative measures 

      Méndez, Valeriano; Catalán, Heliodoro; Rosell Polo, Joan Ramon; Arnó Satorra, Jaume; Sanz Cortiella, Ricardo (Elsevier, 2013)
      Light detection and ranging (LiDAR) technology is beginning to have an impact on agriculture. Canopy volume and/or fruit tree leaf area can be estimated using terrestrial laser sensors based on this technology. However, ...
    • Leaf area index estimation in vineyards using a ground-based LiDAR scanner 

      Arnó Satorra, Jaume; Escolà i Agustí, Alexandre; Vallès Petit, Josep Maria; Llorens Calveras, Jordi; Sanz Cortiella, Ricardo; Masip Vilalta, Joan; Palacín Roca, Jordi; Rosell Polo, Joan Ramon (Springer, 2013)
      Estimation of grapevine vigour using mobile proximal sensors can provide an indirect method for determining grape yield and quality. Of the various indexes related to the characteristics of grapevine foliage, the leaf area ...
    • Discriminating crop, weeds and soil surface with a terrestrial LIDAR sensor 

      Andújar, Dionisio; Rueda-Ayala, Victor; Moreno, Hugo; Rosell Polo, Joan Ramon; Escolà i Agustí, Alexandre; Valero, Constantino; Gerhards, Roland; Fernández-Quintanilla, César; Dorado, José; Griepentrog, Hans-Werner (Molecular Diversity Preservation International (MDPI), 2013)
      In this study, the evaluation of the accuracy and performance of a light detection and ranging (LIDAR) sensor for vegetation using distance and reflection measurements aiming to detect and discriminate maize plants and ...
    • Potential of a terrestrial LiDAR-based system to characterise weed vegetation in maize crops 

      Andújar, Dionisio; Escolà i Agustí, Alexandre; Rosell Polo, Joan Ramon; Fernández-Quintanilla, César; Dorado, José (Elsevier, 2013)
      LiDAR (Light Detection And Ranging) is a remote-sensing technique for the measurement of the distance between the sensor and a target. A LiDAR-based detection procedure was tested for characterisation of the weed vegetation ...
    • Deciduous tree reconstruction algorithm based on cylinder fitting from mobile terrestrial laser scanned point clouds 

      Méndez, Valeriano; Rosell Polo, Joan Ramon; Sanz Cortiella, Ricardo; Escolà i Agustí, Alexandre; Catalán, Heliodoro (Elsevier, 2014)
      Vector reconstruction of objects from an unstructured point cloud obtained with a LiDAR-based system (light detection and ranging) is one of the most promising methods to build three dimensional models of orchards. The ...
    • LIDAR as an alternative to passive collectors to measure pesticide spray drift 

      Gregorio López, Eduard; Rosell Polo, Joan Ramon; Sanz Cortiella, Ricardo; Rocadenbosch Burillo, Francesc; Solanelles Batlle, Francesc; Garcerá, Cruz; Chueca, Patricia; Arnó Satorra, Jaume; Moral Martínez, Ignacio del; Masip Vilalta, Joan; Camp, Ferran; Viana, R.G.; Escolà i Agustí, Alexandre; Gràcia, Felip; Planas de Martí, Santiago; Moltó, Enrique (Elsevier, 2014)
      Pesticide spray drift entails a series of risks and costs in terms of human, animal and environmental well-being. A proper understanding of this phenomenon is essential to minimise these risks. However, most conventional ...
    • Advanced Technologies for the Improvement of Spray Application Techniques in Spanish Viticulture: An Overview 

      Rosell Polo, Joan Ramon; Arnó Satorra, Jaume; Escolà i Agustí, Alexandre; Gil Moya, Emilio; Llorens Calveras, Jordi; Llop, Jordi; Gallart, Montserrat (MDPI, 2014)
      Spraying techniques have been undergoing continuous evolution in recent decades. This paper presents part of the research work carried out in Spain in the field of sensors for characterizing vineyard canopies and monitoring ...
    • Soil water content, runoff and soil loss prediction in a small ungauged agricultural basin in the Mediterranean region using the Soil and Water Assessment Tool 

      Ramos Martín, Ma. C. (Ma. Concepción); Martínez Casasnovas, José Antonio (Cambridge University Press, 2015)
      The aim of the present work was to evaluate the possibilities of using sub-basin data for calibration of the Soil and Water Assessment Tool (SWAT) model in a small (46 ha) ungauged basin (i.e. where the water flow is not ...