Assessment of the Accuracy of a Multi-Beam LED Scanner Sensor for Measuring Olive Canopies

MDPI. CC BYCanopy characterization has become important when trying to optimize any kind of agricultural operation in high-growing crops, such as olive. Many sensors and techniques have reported satisfactory results in these approaches and in this work a 2D laser scanner was explored for measuring canopy trees in real-time conditions. The sensor was tested in both laboratory and field conditions to check its accuracy, its cone width, and its ability to characterize olive canopies in situ. The sensor was mounted on a mast and tested in laboratory conditions to check: (i) its accuracy at different measurement distances; (ii) its measurement cone width with different reflectivity targets; and (iii) the influence of the target’s density on its accuracy. The field tests involved both isolated and hedgerow orchards, in which the measurements were taken manually and with the sensor. The canopy volume was estimated with a methodology consisting of revolving or extruding the canopy contour. The sensor showed high accuracy in the laboratory test, except for the measurements performed at 1.0 m distance, with 60 mm error (6%). Otherwise, error remained below 20 mm (1% relative error). The cone width depended on the target reflectivity. The accuracy decreased with the target density

Relaciones históricas entre olmos y vides

In Spanish, the expression «You cannot ask an elm for pears» denotes something that is impossible. Although its origin is unknown, it can be dated back to the 1st century BC, when appeared the Latin maxim Pirum, non ulmum accedas, si cupias pira (You should go to a pear-tree for pears, not to an elm), a sentence from which we believe the Spanish saying comes. The objective of this paper is to show how the historical relationship of elms and vines can be related to these expressions, because elms did not give pears but, figuratively, did give grapes. The cultivation of vines was soon included among the domestic plants at the beginning of the Neolithic Age. During the Assyrian Empire (7th century BC), vines are represented growing up around pine-like trees. The first documentary evidence of the marriage between elms and vines is found in the Ancient Greece: a wine called Pteleaikós oinos is mentioned, which refers to the region where it was produced, Ptelea (Elm). During the Roman Ages, the cultivation of vines married to elms became more important as it is reflected in the treatises in agriculture. This technique was so common that it appears recurrently as a topic in Poetry and Drama. The classical books were copied during the Middle Ages, and only the Arabian agronomists in the Iberian Peninsula gave new evidence of the relationship between vines and elms in the 12th century. Some four hundred years later the use of elms as props for vines was rare in Spain and, although not to elms, the marriage of vines to trees lasted in the South of Spain until the 19th century. In Italy, elms and vines were even planted together in the 20th century, before the Dutch Elm Disease began to kill the plantations of trees and farmers were forced to replace them with poles.En castellano, la expresión «No se le puede pedir peras al olmo» indica algo imposible. A pesar de que su origen es desconocido, puede situarse en el siglo I A.C., cuando aparece la máxima latina Pirum, non ulmum accedas, si cupias pira (Al peral acude, no al olmo, si quieres peras), de la cual creemos que procede la expresión española. En este trabajo se pretende mostrar que la relación histórica de los olmos y las vides puede estar relacionada con estas expresiones en la medida en que los olmos no daban peras mas, en sentido figurado, daban uvas. La vid fue una de las primeras plantas cultivadas ya desde el comienzo del Neolítico. En el Imperio Asirio (s. VII A.C.), las vides aparecen representadas creciendo alrededor de árboles que se asemejan a pinos. La primera evidencia documental del maridaje de olmos y vides la encontramos en la Grecia Clásica, donde se menciona un vino llamado Pteleaikós oinos que hace referencia a la región dónde se producía, Ptelea (Olmo). Durante la época Romana el cultivo de las vides maridadas a los olmos adquiere mayor importancia, como se refleja en los tratados de agricultura. La práctica fue tan común que aparece de modo recurrente como tópico en la literatura. Los textos clásicos son copiados durante la Edad Media, y sólo los agrónomos árabes de la península Ibérica proporcionan nuevas evidencias de la relación entre vides y olmos ya en el siglo XII. Cuatro siglos después la utilización de olmos como tutores de las vides era rara en España, pero el maridaje de las vides con árboles, aunque no olmos, duró en el Sur de España hasta el siglo XIX. Sin embargo en Italia olmos y vides se plantaban juntos incluso en el siglo XX, antes de que la grafiosis comenzara a matar las plantaciones de árboles y los agricultores se vieran obligados a sustituirlos por postes

Are Notifications a Challenge for Older People?: A Study Comparing Two Types of Notifications

Elderly users are usually not the target of design of mobile applications, and they may have cognitive and physical difficulties. Mobile notifications may help them remember to use an application, promoting adoption and allowing them to become content providers. We developed a mobile application, QuestionReport, that asks users one question per day, and implemented two types of notifications: one that is activated at the same time each day, and one that is activated while using the smartphone. We tested both notification types with 18 users over a period of 8 days, measuring the time it took to answer the question after receiving the notification and their perceptions about each notification style. We found that the ideal time for users to receive a notification depends on their employment status and that users with low digital skills have less confidence in their abilities to use a mobile application such as QuestionReport.

Validation of an interview for study the process of formation of elite judokas

Con el objetivo de analizar el proceso de formación deportiva de los judokas españoles de élite, se diseñó una entrevista semiestructurada de 52 preguntas agrupadas en 6 dimensiones (entorno social, entorno deportivo, psicológica, técnico-táctica, condición física y otros aspectos). Se llevó a cabo un análisis cualitativo y cuantitativo mediante la valoración de 10 expertos. Se analizó la validez de contenido a través del coeficiente V de Aiken, estableciendo un intervalo de confianza del 99 %, y el coeficiente de variación. Para conocer la fiabilidad se pasó la entrevista a judokas de alto nivel en dos momentos distintos y se analizó la consistencia interna por el método del Alfa de Cronbach (0,915) y la fiabilidad test-retest utilizando el coeficiente de correlación intraclase resultando 0,843 (p<0,01). La entrevista reúne suficientes propiedades como para ser considerada una herramienta válida y fiable para estudiar y analizar el proceso de formación de los judokas de éliteIn order to analyze the process of sports training of the Spanish elite judokas , a semistructured interview of 52 questions grouped into 6 domains ( social, sporting environment , psychological , technical and tactical, physical condition and other aspects ) was designed. It was conducted a qualitative and quantitative analysis with 10 experts´ valuation. The validity of content was analysed through the coefficient V Aiken , establishing a 99 % confidence interval, and so the coefficient of variation was analyzed. To know reliability the interview was given to senior judokas in two different moments , and internal consistency was analysed by the Cronbach's alpha method ( 0.915 ) and so test-retest reliability by using the intraclass correlation coefficient resulting 0.843 (p < 0.01 ) . The interview brings enough properties to be considered a valid and reliable tool to study and analyze the formation of elite judoka

Factors that influence the process of formation of the olympic judokas

Con el objetivo de analizar los factores que influyen en el proceso de formación deportiva de los judokas españoles olímpicos, se aplicó una entrevista semiestructurada de 52 preguntas agrupadas en 6 dimensiones (Contexto Deportivo, Contexto Social, Proceso de Formación, Psicológica, Técnico-táctica, Condición Física). Los resultados muestran que los judokas olímpicos se iniciaron en la práctica del Judo a los 6,90 ± 3,02 años, concretamente las mujeres a los 6,80 ± 2,88 años y los hombres algo más tarde, a los 7 ± 3,42 años, el 95% (n=19) influenciados, fundamentalmente, por un familiar. Además, destaca que ninguno de los entrevistados consiguió medalla en categorías inferiores. Para el 75% (n=15) de los judokas olímpicos es muy importante llevar una sincronización del entrenamiento técnico-táctico, de la condición física y de los aspectos psicológicos de forma integradaWith the aim of analizing the factors that have an influence on the sports training process of the olympic Spanish judokas, a semistructured interview of 52 questions grouped in 6 aspects was carried out: Sports Context, Social Context, Training Process, Psychological Condition, Technical-Tactical Condition and Physical Conditon). The results show that olympic judokas began practising judo at the age of 6.90 ± 3.02 years. Specifically, women started at the age of 6.80 ± 2.88, and men slightly later, at the age of 7 ± 3.42 years. 95% (n=19) of them were mainly influenced by a relative. Moreover, it is to be highlighted that none of the interviewees won a medal in low categories. For 75% (n=15) of the olympic judokas, it is very important that technical-tactical training, physical condition training and psychological aspects be synchronised in an integrated wa

Shear band formation in porous thin-walled tubes subjected to dynamic torsion

In this paper, we have performed 3D finite element calculations of thin-walled tubes subjected to dynamic twisting to investigate the effect of porous microstructure on the formation of shear localization bands under simple shear conditions. For that purpose, we have incorporated into the finite element model the porous microstructures of four different additive manufactured metals – aluminium alloy AlSi10Mg, stainless steel 316L, titanium alloy Ti6Al4V and Inconel 718 – for which the void volume fraction varies from ≈ 0.001% to ≈ 2 %, and the voids size between ≈ 6 μm and ≈ 110 μm (Marvi-Mashhadi et al., 2021). For each microstructure, we have created up to 10 realizations varying the spatial location of the voids and the distribution of voids size. The matrix material is elastic/plastic, with yielding defined by the von Mises yield criterion and associated flow rule. The yield stress evolution is considered to be dependent on strain, strain rate and temperature, with parameters corresponding to Titanium and HY-100 Steel, taken from Molinari (1997) and Batra and Kim (1990), respectively. Moreover, we have assumed the deformation process to be adiabatic. The calculations have been performed for shear strain rates ranging from 100 s−1 to 10000 s−1. To the authors’ knowledge, this is the first study ever that simulates dynamic torsion testing of porous materials with actual representation of voids, providing new results which bring to light the influence of porosity on dynamic shear banding under simple shearing. Namely, the numerical calculations have shown that both the location of the shear band and the critical strain leading to the shear band formation depend on the spatial and size distribution of the voids in the specimen, evidencing the influence of material defects on the localization pattern. Notably, the shear band nucleation strain decreases with both the void volume fraction in the specimen and the size of the voids, the size of the largest pore being the main microstructural feature controlling the loss of load carrying capacity of the specimen. In addition, we have carried out a parametric analysis varying the temperature and strain rate sensitivities of the material, and the loading rate. For the strain rates investigated, increasing the loading speed leads to a mild decrease of the shear strain leading to shear band formation, while the strain rate sensitivity is shown to stabilize material behavior and delay localization. Moreover, the numerical results have made apparent that for the hardening materials considered, thermal softening is essential to trigger the shear band formation, so that the porous microstructure alone does not lead to shear localization.The research leading to these results has received funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme. Project PURPOSE, grant agreement 758056. J. C. Nieto-Fuentes acknowledges support from the CONEX-Plus programme funded by Universidad Carlos III de Madrid, Spain and the European Union's Horizon 2020 research and innovation programme, under the Marie Sklodowska-Curie grant agreement 801538

Effect of small-sided games on football players

El objetivo ha sido analizar cómo influyen los juegos reducidos o SSGs sobre la condición física, técnica y los cambios de dirección (CODA) en jugadoras alevines de fútbol femenino. Participan 12 jugadoras de fútbol femenino. Realizaron 14 sesiones de entrenamiento basado en juegos reducidos de fútbol. La muestra presenta valores normales en la prueba de Saphiro-Wilk, además, en la prueba de t de Student muestra que existen diferencias estadísticamente muy significativas (p ≤0,00) en todas las variables físicas analizadas, menos en el caso de la fuerza explosiva. En las variables de técnica nos muestra que existen diferencias significativas en todas las variables analizadas (p ≤0,00). Por último existen correlaciones positivas y estadísticamente significativas entre las distintas variables analizadas. De esta forma podemos considerar los juegos reducidos son un método adecuado y muy ventajoso para el entrenamiento en las etapas iniciales o de formación en jugadoras de fútbolThe objective has been to analyze how small-sided games or SSGs affect physical, technical and changes of direction (CODA) in U12 female soccer players. 12 female soccer players participate. They conducted 14 training sessions based on reduced soccer games. The sample has normal values in the Saphiro-Wilk test, and in the Student's t test it shows that there are statistically very significant differences (p ≤0,00) in all the analyzed physical variables, less in the case of the explosive force. In the technique variables we show that there are significant differences in all variables analyzed (p ≤0,00). Finally, there are positive and statistically significant correlations between the different variables analyzed. In this way we can consider reduced games are a suitable and very advantageous method for training in the initial stages or training in soccer player

Oscillatory patterns in redox gradient materials through wireless bipolar electrochemistry. The dynamic wave-like case of copper bipolar oxidation

Altres ajuts: ICN2 is funded by the CERCA program/Generalitat de Catalunya.Bipolar electrochemistry allows the development of processes in a wireless manner, with reactions occurring at the induced anodes and cathodes of an immersed conducting material in the electrolyte. As a result, a gradient oxidation state may appear along the main axis field on the surface or bulk of the material depending on the type of reaction available at each induced potential. Redox intercalation gradients have been observed, metal anodization, or deposition, and also reactions at the electrolyte in the nearby environment of the poles induced. The complex oxidation of copper and interconversion between phases formed yields in this work an oscillating redox gradient, thanks to the great resistance change when the oxidized phases are formed. Parallel stripes containing mainly CuO, CuO, and Cu(OH) with large resistance are formed perpendicular to the electric field, forming a sequence of secondary dipoles in intermediate Cu stripes, that depends on the external voltage applied, and that oscillates in time at the same spatial coordinates. With longer times, copper solubilizes at the larger induced potential zones, probably as Cu(OH) . A simple finite element electrostatic model defines the complex potential waves induced in the piece. The resulting dynamics offer an example of the complexity of order in unwired conducting materials in wet media, either in catalysis, bioelectrodes, electronics, photovoltaics, or energy storage