7 research outputs found
Nitrogen Use Efficiency in Durum Wheat (Triticum durum Desf.) Grown under Semiarid Conditions in Algeria
The proper and sustainable management of nitrogen fertilization is one of the most common problems of cereal cultivation in semiarid regions, which are characterized by a wide variability in climatic conditions. The current work was conducted to evaluate the effects of nitrogen fertilization on the agronomic and economic aspects of durum wheat cultivated under rainfed semiarid conditions in Algeria and to determine the most efficient nitrogen use efficiency (NUE) among four genotypes that are widespread in the country (tall and short, old and modern genotypes). The four genotypes, Bousselam, MBB, Megress, and GTAdur, were investigated under four nitrogen rates from 0 to 120 kg N ha−1 during three cropping seasons (2016 to 2018). The results indicate that the total nitrogen uptake at maturity (NM), nitrogen uptake by grain (NG), nitrogen harvest index (NHI), NUE and its components, such as nitrogen uptake efficiency (NUpE) and nitrogen utilization efficiency (NUtE), were significantly affected by year, genotype, and nitrogen level. From this study, it appears that higher nitrogen rates improved NM and NG. However, no effects on either grain yield or marginal net return (MNR) were observed; conversely, increased nitrogen levels produced a 13% reduction in the economic return. In other words, in the North African environment, the response to nitrogen is more evident in quality than in yield, which in turn is dependent on the yearly weather conditions and cultivated genotypes. Moreover, nitrogen negatively affected NUE and its components (NUpE, NUtE). On average, NUE displayed low values (14.77 kg kg−1), mostly irregular and highly dependent on weather conditions; in the best year, it did not exceed 60% (19.87 kg kg−1) of the global average value of 33 kg kg−1. Moreover, the modern genotypes Megress (tall) and GTAdur (short) showed the best capacity to tolerate different nitrogen conditions and water shortages, providing relatively superior yields, as well as more effective N use from fertilizers and the soil than the other two genotypes
Learning to Recognize 3D Human Action from A New Skeleton-based Representation Using Deep Convolutional Neural Networks
Recognizing human actions in untrimmed videos is an important challenging task. An effective 3D motion representation and a powerful learning model are two key factors influencing recognition performance. In this paper we introduce a new skeletonbased
representation for 3D action recognition in videos. The key idea of the proposed representation is to transform 3D joint coordinates of the human body carried in skeleton sequences into RGB images via a color encoding process. By normalizing the
3D joint coordinates and dividing each skeleton frame into five parts, where the joints are concatenated according to the order of their physical connections, the color-coded representation is able to represent spatio-temporal evolutions of complex 3D motions,
independently of the length of each sequence. We then design and train different Deep Convolutional Neural Networks (D-CNNs) based on the Residual Network architecture (ResNet) on the obtained image-based representations to learn 3D motion features
and classify them into classes. Our method is evaluated on two widely used action recognition benchmarks: MSR Action3D and NTU-RGB+D, a very large-scale dataset for 3D human action recognition. The experimental results demonstrate that the proposed
method outperforms previous state-of-the-art approaches whilst requiring less computation for training and prediction.This research was carried out at the Cerema Research Center
(CEREMA) and Toulouse Institute of Computer Science Research
(IRIT), Toulouse, France. Sergio A. Velastin is grateful for funding
received from the Universidad Carlos III de Madrid, the European
Union’s Seventh Framework Programme for Research, Technological
Development and demonstration under grant agreement
N. 600371, el Ministerio de Economia, Industria y Competitividad
(COFUND2013-51509) el Ministerio de Educación, cultura y
Deporte (CEI-15-17) and Banco Santander
THE ISSUE. Traffic, Health, Environment; Intelligent Solutions Sustaining Urban Economies.
THE ISSUE is a project within the Regions of Knowledge scheme funded through the European Commission’s Seventh Framework Programme. THE ISSUE focuses on Traffic, Health and Environment to achieve Intelligent Solutions for Sustaining Urban Economies by bringing together innovative research-driven clusters to coordinate European research and technology development in six areas. These areas are Intelligent Transportation Systems; transport impacts on urban mobility; transport greening; intermodal regional transport; safety and security of citizens; and associated economic, health and environmental impacts. THE ISSUE project particularly addresses the use of space technologies from satellite remote sensing and navigation, as well as GIS and computer intelligence technologies in transport-related sectors. This paper looks into the general presentation of the project and the first results.EU FP7 Regions Of Knowledge projec
Contrôle de la température durant le processus de dégradation d'un acier Z12CNS20 en frottement avec un acier Z200C13
La température de contact lors des essais
d'usure varie d'une manière spontanée et aléatoire. Cette
température de contact dépend essentiellement de la nature du couple
des matériaux en contact de la charge et de la vitesse. Cependant la
mesure de la température est très difficile à effectuer compte
tenu du choix de l'endroit de prise de la température et des
phénomènes d'évacuation de la chaleur et de la dissipation de
l'énergie. Dans ce travail nous exposons une méthode très simple
de mesure de la température et nous étudions par conséquent la
variation de la température du Z12CNS20 Z200C13.
Au cours des essais d'usure pour différentes vitesses de glissement,
nous montrons en effet que la température augmente d'une manière
progressive en fonction de la vitesse puis elle s'élève brutalement
au fur et à mesure qu'on se rapproche du point de contact, et enfin nous
prouvons par observation métallographique que l'échantillon subit un
écoulement plastique provoqué par l'élévation de la
température en fonction de la vitesse
An approach for protecting transport infrastructure
International audienceScientific and technological innovations are often sources of new vulnerabilities, hazards and risks impacting equipment, systems, processes, organization, and human behaviours. The issues of safety, security, performance, and their management in a holistic approach are quickly becoming essential for every industrial sector. This article discusses safety and security policy focused on the protection of critical railway infrastructure. The article suggests a global approach for risk appraisal and threat assessment in the railway sector, and highlights some of the technologies for the monitoring and surveillance of rail linear infrastructures