Aplicación de un sistema de información geográfica para visualizar vías pecuarias y obtener información sobre las mismas a partir de imágenes de satélite SPOT

Sin resume

Application of a force sensor to improve the reliability of measurement with articulated arm coordinate measuring machines

A study of the operator contact force influence on the performance of Articulated Arm Coordinate Measuring Machines (AACMMs) is presented in this paper. After developing a sensor capable of measuring the contact force applied by an operator, a ring gauge has been used to analyse the relationship between the contact force and diameter and form errors measured with the AACMM. As a result, contact force has been proved as one of the main factors influencing the AACMM performance. A probe deflection model based on the Finite Element Method (FEM) has been also proposed in order to obtain the AACMM probe deflection caused by contact force. This allows measurement correction by comparing them with reference values, specifically, a ring gauge. Experimental test results show a significant measurement improvement that minimizes diameter error. Finally, an uncertainty evaluation for the contact force sensor and AACMM measurements with and without probe deflection model has been carried out in order to validate the ability of the sensor and the methodology followe

Evaluation of the influence of post-processing on the optical inspection accuracy of additively manufactured parts

[EN] Optical measurement systems are important techniques for rapid inspecting additively manufactured parts by techniques such as selective laser melting (SLM). Depending on their application, SLM parts require post-processes such as sandblasting or heat treatment, commonly applied in order to improve their surface finish or mechanical properties, respectively. These post-processes modify the parts surface characteristics, and therefore the suitability for optical inspection. This work evaluates the influence of these SLM post-processes on optical inspection. For this, a test part, manufactured in 17-4PH stainless steel using a 3DSystems ProX100 machine, was optically measured using a structured light scanner and compared to the values obtained from contact measurements (reference values). Both optical and contact measurements were performed under three conditions: as-built, post sandblasting, and post sandblasting and subsequent heat treatment. The analysis results show that applying the sandblasting postprocessing provides a surface finish to the SLM parts suitable for optical inspection. This postprocess allows precise inspection of this type of parts, reaching values close to those obtained by contact. Likewise, it is concluded that the used structured blue-light scanner is suitable for inspecting SLM parts.SIMinisterio de Ciencia, Innovación y UniversidadesInstituto Universitario de Tecnología Industrial (SV-18-1-GIJON-1-06 and SV-19-GIJON-1-14

New procedure for qualification of structured light 3D scanners using an optical feature-based gauge

[EN] This work evaluates the performance and operative limits to the dimensional accuracy of 3D optical scanning based on blue-light fringe projection technology. This technology, also known as structured light 3D scanning, is widely used in many reverse engineering applications. It allows the user to quickly capture and create point-clouds, by using images taken at different orientations of white-or blue-light fringe projected patterns on the part. For the survey, a large and feature-based gauge has been used with specific optical properties. The gauge is endowed with canonical geometrical features made of matt white ceramic material. The gauge was calibrated using a coordinate measuring machine (CMM) by contact. Therefore, it is possible to compare the measurements obtained by the structured blue-light sensor with those obtained by the CMM, which are used as reference. In the experimentation, the influence of the scanner software in the measurement results was also analysed. Besides, different tests were carried out for the different fields of view (FOV) of the sensor. The survey offers some practical values and limits to the accuracy obtained in each configuration.SIMinisterio de Economía y Competitividad de EspañaJunta de Castilla y Leó

Goodness-of-fit tests for the functional linear model based on randomly projected empirical processes

We consider marked empirical processes indexed by a randomly projected functional covariate to construct goodness-of-fit tests for the functional linear model with scalar response. The test statistics are built from continuous functionals over the projected process, resulting in computationally efficient tests that exhibit root-n convergence rates and circumvent the curse of dimensionality. The weak convergence of the empirical process is obtained conditionally on a random direction, whilst the almost surely equivalence between the testing for significance expressed on the original and on the projected functional covariate is proved. The computation of the test in practice involves calibration by wild bootstrap resampling and the combination of several p-values, arising from different projections, by means of the false discovery rate method. The finite sample properties of the tests are illustrated in a simulation study for a variety of linear models, underlying processes, and alternatives. The software provided implements the tests and allows the replication of simulations and data applications.Supported by projects MTM2014-56235-C2-2-P and MTM2017-86061-C2-2-P from the Spanish Ministry of Economy, Industry and Competitiveness. Supported by projects MTM2013-41383-P and MTM2016-76969-P from the Spanish Ministry of Economy, Industry and Competitiveness, and the European Regional Development Fund; project 10MDS207015PR from Dirección Xeral de I + D, Xunta de Galicia

Influencia del acabado superficial en el digitalizado con sensores de triangulación por láser

El presente trabajo trata sobre la medida de la influencia que los distintos acabados superficiales tienen sobre la precisión y calidad del digitalizado utilizando sensores láser de triangulación. Entre el gran número de parámetros que influyen en la calidad del digitalizado, se analiza la influencia de la rugosidad. Para ello se ha establecido un procedimiento que permite restringir la influencia de otras variables y que, al mismo tiempo, proporciona una excelente repetibilidad y reproducibilidad. Este procedimiento se ha aplicado a distintos procesos de fabricación que dan lugar a muy distintos acabados superficiales. De esta forma se han establecido ciertas correlaciones cuantificando, además de la influencia de la rugosidad en la nube de puntos, la forma espacial que adopta su dispersión y la intensidad optima para cada proces

Proposal of design rules for improving the accuracy of selective laser melting (SLM) manufacturing using benchmarks parts

[EN] Purpose: Among the different methodologies used for performance control in precision manufacturing, the measurement of metrological test artefacts becomes very important for the characterization, optimization and performance evaluation of additive manufacturing (AM) systems. The purpose of this study is to design and manufacture several benchmark artefacts to evaluate the accuracy of the selective laser melting (SLM) manufacturing process. Design/methodology/approach: Artefacts consist of different primitive features (planes, cylinders and hemispheres) on sloped planes (0°, 15°, 30°, 45°) and stair-shaped and sloped planes (from 0° to 90°, at 5° intervals), manufactured in 17-4PH stainless steel. The artefacts were measured optically by a structured light scanner to verify the geometric dimensioning and tolerancing of SLM manufacturing. Findings: The results provide design recommendations for precision SLM manufacturing of 17-4PH parts. Regarding geometrical accuracy, it is recommended to avoid surfaces with 45° negative slopes or higher. On the other hand, the material shrinkage effect can be compensated by resizing features according to X and Y direction. Originality/value: No previous work has been found that evaluates accuracy when printing inwards (pockets) and outwards (pads) geometries at different manufacturing angles using SLM. The proposed artefacts can be used to determine the manufacturing accuracy of different AM systems by resizing to fit the build envelope of the system to evaluate. Analysis of manufactured benchmark artefacts allows to determine rules for the most suitable design of the desired parts.SIThe authors gratefully acknowledge the financial support provided by the Junta de Castilla y León and FEDER (project ref. LE027P17)

Encuesta de percepción sobre riesgos del sistema Financiero - Enero de 2023

En este informe se presentan los resultados de la Encuesta de Percepción Sobre Riesgos del Sistema Financiero, la cual busca identificar la perspectiva de diferentes agentes de la economía frente a los riesgos y vulnerabilidades más importantes que enfrenta el sector financiero, y evaluar cuál es el nivel de confianza que tienen en su estabilidad

Identifying Optimal Zones for Avocado (Persea americana Mill) Cultivation in Iberian Peninsula: A Climate Suitability Analysis

In recent decades, the cultivation of avocados (Persea americana Mill) has expanded throughout the Iberian Peninsula, with most of the production occurring on the Southern Atlantic and Mediterranean Coast, as well as in the Canary Islands. This expansion is due to high demand and high prices, which have made the crop very attractive. However, climatic suitability criteria have not always been followed, putting sustainability at risk. Avocados originate from tropical and subtropical areas and have very specific climatic requirements that must be met to ensure good production. This study analyzed the key climatic variables, including winter cold damage, pollen viability and flowering and fruit set temperatures. Using daily climate data from 1975 to 2022, advanced spatial analysis techniques were applied to produce suitability maps. The results indicate that the expansion of the crop is possible in certain areas of Southern Andalusia but not in the rest of the peninsula. Variables associated with low temperatures, such as cold damage (temperatures below 0 ◦C in winter) and conditions unfavorable for fruit set (minimum daily temperatures below 10 ◦C in spring), have been identified as the most restrictive factors. Specifically, the number of days with minimum temperatures above 10 ◦C in March and April appears to be the most limiting climatic factor for avocado cultivation in the Iberian Peninsula and the Balearic Islands. Andalusia and the Valencian Community have been identified as the most climatically suitable regions for avocado cultivation, with approximately 1,500,000 hectares recognized as potentially suitable for avocado production. This work provides valuable insights into the potential for sustainable agricultural intensification, the sustainability of agricultural decision-making and resilience to climate change.This research was funded by the Junta de Extremadura and the European Regional Development Fund (ERDF) through the GR18088 (Research Group RNM028)

Encuesta de percepción sobre riesgos del sistema Financiero - Junio de 2023

En este informe se presentan los resultados de la Encuesta de Percepción Sobre Riesgos del Sistema Financiero, la cual busca identificar la perspectiva de diferentes agentes de la economía frente a los riesgos y vulnerabilidades más importantes que enfrenta el sector financiero, y evaluar cuál es el nivel de confianza que tienen en su estabilidad