Simulations numériques de l'évolution des fonds et effet du mélange turbulent sur le transport sédimentaire:Application au remplissage d'une fosse d'extraction

International audienceLe profil linéaire de longueur de mlange $l_{m}=\kappa z$ classiquement utilisé, ne permet pas d'obtenir le profil de vitesse logarithmique observ\é expérimentalement, et sa validité est limitée aux domaines de faible rugosité (conditions aux limites du type 'fond lisse'). Dans ce travail, nous proposons trois types de profils de longueur de mélange $l_{m}(z)$ ainsi que les profiles de vitesses de mélange associés. Les résultats obtenus, sont testés sur des cas académiques et comparés aux résultats expérimentaux de remplissage d'une fosse d'extraction issus des essais présentés dans le projet Européen Sandpit

Modélisation numérique des processus de transport des sédiments et de l'évolution des fonds

International audienceWe propose a new mixing length profile, based on an extension of von Kármán similarity hypothesis, as well as the associated mixing velocity profile. This profile was compared with other profiles and was tested on three academic and experimental cases. The validation of the model was made from a set of reference examples and concerns the erosion of a bottom of sand in a uniform flow, and the filling of an extraction pit resulting from the tests presented in the European project SANDPIT.On propose un nouveau profil de longueur de mélange lm (z) , basé sur une extension de l'hypothèse de similitude de von Kármán, ainsi que le profil de vitesse de mélange associé. Ce profil a été comparé à d'autres profils et testé sur trois cas test académiques et expérimentaux. La validation du modèle a été effectuée à partir d'un ensemble d'exemples de références et concernent l'érosion d'un fond de sable érodable dans un écoulement uniforme en canal, et le remplissage d'une fosse d'extraction issus des essais présentés dans le projet Européen SANDPIT

Effects of hospital facilities on patient outcomes after cancer surgery: an international, prospective, observational study

Background Early death after cancer surgery is higher in low-income and middle-income countries (LMICs) compared with in high-income countries, yet the impact of facility characteristics on early postoperative outcomes is unknown. The aim of this study was to examine the association between hospital infrastructure, resource availability, and processes on early outcomes after cancer surgery worldwide.Methods A multimethods analysis was performed as part of the GlobalSurg 3 study-a multicentre, international, prospective cohort study of patients who had surgery for breast, colorectal, or gastric cancer. The primary outcomes were 30-day mortality and 30-day major complication rates. Potentially beneficial hospital facilities were identified by variable selection to select those associated with 30-day mortality. Adjusted outcomes were determined using generalised estimating equations to account for patient characteristics and country-income group, with population stratification by hospital.Findings Between April 1, 2018, and April 23, 2019, facility-level data were collected for 9685 patients across 238 hospitals in 66 countries (91 hospitals in 20 high-income countries; 57 hospitals in 19 upper-middle-income countries; and 90 hospitals in 27 low-income to lower-middle-income countries). The availability of five hospital facilities was inversely associated with mortality: ultrasound, CT scanner, critical care unit, opioid analgesia, and oncologist. After adjustment for case-mix and country income group, hospitals with three or fewer of these facilities (62 hospitals, 1294 patients) had higher mortality compared with those with four or five (adjusted odds ratio [OR] 3.85 [95% CI 2.58-5.75]; p<0.0001), with excess mortality predominantly explained by a limited capacity to rescue following the development of major complications (63.0% vs 82.7%; OR 0.35 [0.23-0.53]; p<0.0001). Across LMICs, improvements in hospital facilities would prevent one to three deaths for every 100 patients undergoing surgery for cancer.Interpretation Hospitals with higher levels of infrastructure and resources have better outcomes after cancer surgery, independent of country income. Without urgent strengthening of hospital infrastructure and resources, the reductions in cancer-associated mortality associated with improved access will not be realised

Smart environmental data management system into a cattle building

The climatic atmosphere in which cattle live is an essential parameter of their environment because of its critical role in their productivity. An adapted cattle building must help to mitigate the effects of climatic stress and allow the farmer to properly control the climatic atmosphere during the production cycle. The most important factors influencing the climatic atmosphere inside a cattle building are temperature, humidity, and greenhouse gas emissions. We propose a case study for a wireless sensor network model placed on a cattle farm, in which each measurement node “mote” collects environmental data (temperature, humidity, and emission gas), in order to control the building's climate, this data is stored and managed in a remote database. We will present HBase, a NoSQL database management system, based on the concept of distributed storage, a column-oriented database that provides the read/write access to data on the HADOOP HDFS file system in real-time. The storage results presented in this paper are obtained via a java code that can connect with the HBase database, in order to store the received data at every second from each node constituting the measurement system via HTTP requests

Remote Sensing for Spatio-temporal Mapping of Land surface temperature and Surface Energy Fluxes in the Bouregreg-Chaouia Region of Morocco

In recent decades, the Bouregreg Chaouia region has been subject to urban growth and a reduction in agricultural land in this region, which has changed its environmental variables and made it vulnerable to climate change. This work raises the spatiotemporal monitoring of land use and certain environmental parameters (vegetation cover, albedo, surface temperature from 1987 to 2015 by exploring intelligent spatial data in the region. The remote sensing products were computed from Landsat 5 TM, Landsat 7 ETM+ and Landsat 8 Oli/TIRS images obtained during the dry seasons 1987, 2000 and 2015. The results showed a reduction in NDVI vegetation index (∼0.86 in 1987 to ∼0. 56 in 2000 to ∼ 0.54 in 2015) and with an increase in surface albedo (0.51 in 1987 to 0.52 in 2000 to 0. 69 in 2015), temperature (∼67°C in 1987 to 54°C in 2000 to 40°C in 2015) and to understand the impact of urbanization on the variation of environmental parameters, the evolution of the built-up area has been followed as a determining factor. However, it recorded 3.27% surface area in 1987 to 7.45% in 2000 to 28.18% in 2015. Indeed, the contribution of new technologies (GIS and remote sensing) is essential for better management and monitoring of the impact of urban expansion on the state of the environment. The results obtained remain so promising and highlight the contribution and feasibility of intelligent spatial data to assess the evolution of the urban environment on a large scale

Study of natural degradation effect on lignocellulose fibers of archaeological cedar wood: monitoring by Fourier Transform Infrared (FTIR) spectroscopy

The present work aims at elucidating the changes in the chemical composition of Moroccan cedar wood during exposure time to the natural degradation process. Correlation of these changes with certain physical properties and performance of this polymeric material were proposed. Four archaeological Cedrus atlantica wood samples dating from the 16th, 17th, 19th and 21st centuries were analyzed using Fourier Transform Infrared spectroscopy. The infrared spectroscopic analyses demonstrated in detail the significant changes that occurred in different molecular groups of lignocelluloses fibers, as evidenced by the decrease of band intensities related to the carbohydrates and lignin. The influence of the natural degradation process on these fibers was enhanced by the gradual decline in fingerprint (1800-800cm-1) related to the cellulose amount accompanied by the detection of new carbonyl band at 1650cm-1 attributed to the C=O quinone suggesting the lignin’s oxidation

Design of a Particle Swarm Optimized Photovoltaic system during various partial shading conditions

This work discusses an enhanced photovoltaic system using the Particle Swarm Optimization algorithm. The proposed method has been evaluated under several scenarios of partial shading, and the results obtained are contrasted with the Perturb and Observe technique. Hence, it has shown its effectiveness in locating the global maximum power point whatever the meteorological conditions, especially in inhomogeneous conditions. This technique makes it possible to enhance the effectiveness of the photovoltaic system studied because it makes it possible to minimize the loss of power in the case of non-homogeneous irradiation conditions

Scanning Electron Microscopy examination of the surface of softwood attacked by fungus

The morphological structure of the surface of four Cedrus atlantica softwood samples was monitored by scanning electron microscope. The obtained results have shown formation of cracks on the surface of samples with deterioration of the majority of cellulosic fibers. The alteration of wood structure and decomposition of carbohydrates exploited by scanning electron microscopy images could act as a confidential sign of an advanced stage of wood decay by biological attacks, leading upon time to the extinction of this natural wealth. It appeared that the studied samples were attacked by brown-rot fungus selectively decaying the cell wall of softwood materials. The scanning electron microscope morphological observation revealed that microfibril distribution was heterogeneous and dynamic contact angles increase significantly during exposure to the non-controlled environmental conditions