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Control and Power Management of a 24-Hour DC Microgrid Improved Model
No full textInternational audienceIn recent decades, the microgrid concept emerged as a solution to electrify remote areas and integrate renewable energy sources to mitigate environmental pollution. Owing to the evolution of power electronic devices, the ease of control, and the improved efficiency and reliability, DC microgrids are gaining increased interest. Many kinds of research address the hierarchical control in DC microgrids to accomplish multiobjectives. On the first and second levels, the control targets fast dynamic variables to achieve its objectives. Yet, on a third control level, general management functionalities are executed. Many of these management functionalities target the system variables with a slower dynamic and so, to prove the effectiveness of the proposed hierarchical control, a 24-hour model simulation is required. The wide time-range dynamics of the existing system variables make the 24-hour modeling subject a complicated matter especially, on standard computers with conventional performances. To overcome this problem, this paper proposes a 24-hour DC microgrid model which offers the best tradeoff between model precision, complexity, and simulation speed. The multi-objectives hierarchical control is adopted: on a first and second control level, several averaging techniques are introduced and compared to a detailed reference model in terms of accuracy and calculation step size. DC microgrid's general management strategy is adopted on the third control level. Simulation tests are performed on MATLAB/Simulink software to prove the viability of the proposed 24-hour model
Le traitement de la diversité religieuse dans les établissements secondaires catholiques sous contrat à La Réunion : un effet territoire et du « vivre ensemble » ?
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Labilité ou créolisation de la laïcité scolaire ? Le cas des espaces « écotonaux » des villes de la Réunion
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Multi-armed bandit algorithms over DASH for multihomed client
No full textInternational audienceThere is an expanding request from the mobile clients of video traffic which has come to over the most recent two years the greater part of all the mobile data traffic. The challenge of providing the clients excellent video streaming is expected principally to the constrained transfer speed which makes it important to misuse the rising decent variety of mobile video spilling and get to systems. For enhancing the video quality received by "multi-homed client" (i.e., clients with multiple network interfaces), a network selection algorithm based on the Multi-Armed Bandit heuristic is proposed on top of the most broadly utilized standard for video streaming Dynamic Adaptive Streaming over HTTP (DASH). For choosing the best network at each progression powerfully, DASH gives mobile video quality dependent on the apparent exhibition from the pre-owned system association through the Adaptive Bitrate Rules (ABR) without investigating the system conditions through the other network(s) which could give better quality. Subsequently, a few alterations for DASH ABR is required to enhance the video quality. Two of the MAB algorithms (UCB and Epsilon Greedy) were embraced for improving MPEG-Dash. The investigations are performed through a proving ground execution to show that UCB surpasses Epsilon Greedy, in stable system conditions, regarding goodput received by the Dash customer. Additionally, UCB can discover the harmony between investigating new choices, and abusing the triumphant variation. Index Terms-DASH, Multi-homed, video streaming
Joint Modeling of TDD and Decoupled Uplink/Downlink Access in 5G HetNets with Multiple Small Cells Deployment
No full textInternational audienceDue to highly variant traffic in downlink (DL) and uplink (UL) in heterogeneous networks (HetNets), dynamic time-division duplexing (TDD) is proposed to dynamically allocate UL and DL resources. Under the same circumstances, downlink and uplink decoupled access (DUDA) is introduced to balance between UL and DL transmissions and to further improve the system performance. Rather than belonging to a specific cell, a mobile user can receive the downlink traffic from one base station (BS) and send uplink traffic through another BS. In this article, we analytically investigate a joint TDD and DUDA statistical model with multiple small cells deployment. This model is based on a geometric probability approach. Taking all possible TDD subframes combinations between the macro and small cells, coupled and decoupled cell associations strategies are investigated in details. We derive analytical expressions for the capacity and the interference, considering a network of one macro cell and multiple small cells. We build on the derived capacity expressions to measure the decoupling gain and thus, identify the location of the interferer small cell where the decoupled mode maintains a higher gain in both DL and UL. Monte-Carlo simulations results are presented to validate the accuracy of the statistical model
Safety and efficacy of pazopanib as a second-line treatment and beyond for soft tissue sarcomas: A real-life tertiary-center experience in the MENA region
No full textInternational audienceINTRODUCTION: Sarcomas are uncommon malignancies. No advances have been recently achieved despite multiple efforts. Pazopanib is a safe and effective tyrosine kinase inhibitor used in managing soft tissue sarcomas (STS) after chemotherapy failure. However, its use is limited in developing countries and no efficacy data exist from our region. We aimed to study the efficacy of pazopanib in our population, characterized by response rates of patients with chemotherapy-refractory advanced STS receiving pazopanib. Secondary endpoints included progression-free survival (PFS), overall survival (OS) and toxicity profile. MATERIALS AND METHODS: 15 patients (age≥18 year) diagnosed with advanced STS, refractory to first-line chemotherapy, receiving pazopanib as ≥second-line therapy in one tertiary center in Lebanon were included between January 1st, 2014 and October 31st, 2018. Patient and disease characteristics, disease evaluation, as well as tolerance to treatment, were extracted from charts retrospectively. Statistical analysis was done using SPSS version 24. RESULTS: The mean age was 48.6 [19-66] years. Eleven patients (73.3%) received pazopanib in second-line, whereas four patients (26.7%) received it in third-line. Thirteen patients (86.7%) progressed, and two patients (13.3%) had stable disease. The median PFS was three months [1-19] and the mean OS was 25.4 months [17.2-33.6]. Five patients required dose-reductions due to poor tolerance. CONCLUSION: Conclusions cannot be drawn due to small patient numbers. However, given the 3-month PFS, 13% of patients maintaining stable disease, and tolerable safety profile, it is reasonable to incorporate pazopanib in STS treatment. More focused studies with larger patient populations need to be done in Lebanon
Effect of curve location on the severity index for adolescent idiopathic scoliosis: a longitudinal cohort study
No full textInternational audienceObjectivesAdolescent idiopathic scoliosis (AIS) is the most common spinal disorder in children. A severity index was recently proposed to identify the stable from the progressive scoliosis at the first standardized biplanar radiographic exam. The aim of this work was to extend the validation of the severity index and to determine if curve location influences its predictive capabilities.MethodsAIS patients with Cobb angle between 10° and 25°, Risser 0–2, and no previous treatment were included. They underwent standing biplanar radiography and 3D reconstruction of the spine and pelvis, which allowed to calculate their severity index. Patients were grouped by curve location (thoracic, thoracolumbar, lumbar). Patients were followed up until skeletal maturity (Risser ≥ 3) or brace prescription. Their outcome was compared to the prediction made by the severity index.ResultsIn total, 205 AIS patients were included; 82% of them (155/189, 95% confidence interval [74–90%]) were correctly classified by the index, while 16 patients were unclassified. Positive predictive ratio was 78% and negative predictive ratio was 86%. Specificity (78%) was not significantly affected by curve location, while patients with thoracic and lumbar curves showed higher sensitivity (≥ 89%) than those with thoracolumbar curves (74%).ConclusionsIn this multicentric cohort of 205 patients, the severity index was used to predict the risk of progression from mild to moderate scoliosis, with similar results of typical major curve types. This index represents a novel tool to aid the clinician and the patient in the modulation of the follow-up and, for progressive patients, their decision for brace treatment
Enquêtes géographiques a Ras Shamra - Ougarit : les acquis
No full textInternational audienceThe geographical surveys undertaken at Ras Shamra and its wider region, i.e. the borders of the ancient kingdom of Ugarit, aim to better understand its past and present landscapes in order to identify the constraints and opportunities provided by the environment, which hindered or, by contrast, facilitated the development of human settlement. The surveys also seek to elucidate the composite environmental strands that make up the particularity of a region. To better understand the changes in land-use conditions, and to differentiate the plausible from the possible, we analysed different components of the environment, including static (situation, relief, lithology, climate, hydrography) and dynamic (thermo-pluviometric regimes, water resources, edaphic support, plant cover, coastline, human impacts) factors. The ancient kingdom of Ugarit was particularly favorable to human settlement, both because of its location, its available resources and its agricultural potential. Although, the environment cannot solely explain the extraordinary development and influence of the city of Ugarit during the Bronze Age, it is clear that the environment has shaped the “geographical personality” of the region, and that it has favored the emergence of a prosperous capital and its kingdom.Les enquêtes géographiques réalisées à Ras Shamra et dans sa région, soit dans le périmètre de l’antique royaume d’Ougarit, visent à mieux comprendre la réalité des paysages, tant actuels que passés, afin de cerner les contraintes et les opportunités liées à l’environnement, qui entravaient ou au contraire aidaient au développement du peuplement et de la mise en valeur. Elles cherchent aussi à préciser les réalités composites qui font la particularité d’une région. Pour cela elles se fondent sur l’analyse des différentes composantes du milieu, statiques (situation, relief, lithologie, zone climatique, hydrographie...) et dynamiques (régime thermo-pluviométrique, ressources hydriques, support édaphique, couvert végétal, trait de côte, anthropisme...), pour mieux cerner les évolutions des conditions d’occupation du sol et discerner le plausible du possible. La région se révèle être particulièrement favorable à l’implantation humaine, tant du fait de sa localisation que des ressources disponibles et du potentiel agricole. Si, évidemment, ce constat ne peut pas à lui seul expliquer l’extraordinaire développement et le rayonnement de la cité d’Ougarit à l’âge du Bronze, il apparaît clairement que les composantes du milieu fondent, du fait de leur combinaison originale, la « personnalité géographique » de ce territoire et qu’elles n’ont pu que favoriser l’émergence, en ce lieu particulier, d’une capitale et d’un royaume prospères
Energy-efficient field-oriented control for induction motors taking core losses into account
No full textInternational audienceThe control strategy is an essential element in the improvement of electric motor energy efficiency through flux adaptation, according to the operating conditions. Therefore, the goal of this paper is to present an energy-efficient field-oriented control structure for squirrel-cage induction motors (IM), improving their energy efficiency and taking into consideration the core loss effect. For this purpose, optimal flux is computed in off-line calculations based on an improved IM dynamic model including core losses. These optimal values are stored in a torque-speed look-up table used to provide the flux reference of the control structure. Simulation and experimental results validate the proposed optimized field-oriented control showing the improvement in energy efficiency and the reduction in power losses. Experimental tests also confirm the improvement of the proposed method, compared to an industrial optimization technique and a state-of-art approach
WAO-ARIA consensus on chronic cough – Part 1: Role of TRP channels in neurogenic inflammation of cough neuronal pathways
No full textInternational audienceBackground: Cough features a complex peripheral and central neuronal network. The function of the chemosensitive and stretch (afferent) cough receptors is well described but partly understood. It is speculated that chronic cough reflects a neurogenic inflammation of the cough reflex, which becomes hypersensitive. This is mediated by neuromediators, cytokines, inflammatory cells, and a differential expression of neuronal (chemo/stretch) receptors, such as transient receptor potential (TRP) and purinergic P2X ion channels; yet the overall interaction of these mediators in neurogenic inflammation of cough pathways remains unclear. Objectives: The World Allergy Organization/Allergic Rhinitis and its Impact on Asthma (WAO/ ARIA) Joint Committee on Chronic Cough reviewed the current literature on neuroanatomy and pathophysiology of chronic cough. The role of TRP ion channels in pathogenic mechanisms of the hypersensitive cough reflex was also examined. Outcomes: Chemoreceptors are better studied in cough neuronal pathways compared to stretch receptors, likely due to their anatomical overabundance in the respiratory tract, but also their distinctive functional properties. Central pathways are important in suppressive mechanisms and behavioral/affective aspects of chronic cough. Current evidence strongly suggests neurogeni