1,225 research outputs found

    Context-Aware Handover Policies in HetNets

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    Next generation cellular systems are expected to entail a wide variety of wireless coverage zones, with cells of different sizes and capacities that can overlap in space and share the transmission resources. In this scenario, which is referred to as Heterogeneous Networks (HetNets), a fundamental challenge is the management of the handover process between macro, femto and pico cells. To limit the number of handovers and the signaling between the cells, it will hence be crucial to manage the user's mobility considering the context parameters, such as cells size, traffic loads, and user velocity. In this paper, we propose a theoretical model to characterize the performance of a mobile user in a HetNet scenario as a function of the user's mobility, the power profile of the neighboring cells, the handover parameters, and the traffic load of the different cells. We propose a Markov-based framework to model the handover process for the mobile user, and derive an optimal context-dependent handover criterion. The mathematical model is validated by means of simulations, comparing the performance of our strategy with conventional handover optimization techniques in different scenarios. Finally, we show the impact of the handover regulation on the users performance and how it is possible to improve the users capacity exploiting context information

    Weak nodes detection in urban transport systems: Planning for resilience in Singapore

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    The availability of massive data-sets describing human mobility offers the possibility to design simulation tools to monitor and improve the resilience of transport systems in response to traumatic events such as natural and man-made disasters (e.g. floods terroristic attacks, etc...). In this perspective, we propose ACHILLES, an application to model people's movements in a given transport system mode through a multiplex network representation based on mobility data. ACHILLES is a web-based application which provides an easy-to-use interface to explore the mobility fluxes and the connectivity of every urban zone in a city, as well as to visualize changes in the transport system resulting from the addition or removal of transport modes, urban zones, and single stops. Notably, our application allows the user to assess the overall resilience of the transport network by identifying its weakest node, i.e. Urban Achilles Heel, with reference to the ancient Greek mythology. To demonstrate the impact of ACHILLES for humanitarian aid we consider its application to a real-world scenario by exploring human mobility in Singapore in response to flood prevention.Comment: 9 pages, 6 figures, IEEE Data Science and Advanced Analytic

    Comparison of Centella with flavonoids for treatment of symptoms in hemorrhoidal disease and after surgical intervention: A randomized clinical trial

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    Gli effetti dei flebotonici sono stati valutati per il tempo di arresto del sanguinamento e il tempo di scomparsa dell'irritazione anale in 130 pazienti affetti da malattia emorroidaria, tempo di arresto del sanguinamento e tempo di scomparsa del dolore dopo intervento [emorroidectomia (in 31 pazienti) oppure incisione e drenaggio di trombosi emorroidaria (in 34 pazienti)]. Queste valutazioni sono state fatte nel breve periodo di tempo 0-42 gg. Sessanta pazienti randomizzati hanno ricevuto la procedura di routine (sia conservativa che chirurgica) (gruppo di controllo C). Il gruppo dei pazienti che hanno ricevuto il trattamento con flebotonici (sia conservativo che chirurgico) è stato suddiviso in due sottogruppi: quello trattato con flavonoidi (Gruppo A, n = 73) e quello trattato con Centella (Gruppo B, n = 66). Il tempo di scomparsa del sanguinamento è stato verificato dal Giorno 0 fino al Giorno 42. La guarigione è stata stimata con il metodo Kaplan-Meier, il test Kruskal-Wallis è stato utilizzato per valutare le variazioni del punteggio VAS per studiare il dolore (dopo intervento per emorroidectomia oppure incisione e drenaggio di trombosi emorroidaria), oppure irritazione anale nei pazienti trattati conservativamente. Il tempo medio di emorragia è stato di 2 settimane per i gruppi A e B; 3 settimane per il gruppo C. Il confronto dei punteggi VAS tra i gruppi (irritazione): A vs C, p = 0,007; B vs C, p = 0,041; e A vs B, rispettivamente p = 0,782. Per quanto riguarda gli operati con emorroidectomia, il tempo di arresto del sanguinamento è stato rispettivamente di 3 e 4 settimane nei gruppi A e B, 5 settimane nel gruppo C. L'istopatologia ha mostrato un'associazione tra flavonoidi e fibrosi emorroidaria (p = 0,008). I flebotonici hanno mostrato significativi effetti benefici sia negli operati che nei pazienti trattati conservativamente. Tra i flebotonici, i flavonoidi sono stati più efficaci contro il sanguinamento e l'irritazione anale.Phlebotonics' effects were evaluated to reduce time-to-stop bleeding and anal irritation in 130 patients who complained of hemorrhoidal disease (HD); bleeding and pain after hemorrhoidectomy (31 patients) and hemorrhoidal thrombosis (34 patients) in the short time. Sixty patients were randomized to receive the routine treatment (both conservative and surgical) (control Group C). The treated group (both conservative and surgical) was divided into two subgroups: one treated with flavonoids (Group A, n = 73), the other with Centella (Group B, n = 66). Time-to-stop bleeding was checked at baseline and checkups (0 up to day 42). Healing was estimated with Kaplan-Meier method, the Kruskal-Wallis test estimated changes in the VAS scores. The HD median time-to-stop bleeding was 2 weeks for Groups A and B; 3 weeks for Group C. VAS scores comparison among Groups (irritation): A vs C, p = 0.007; B vs C, p = 0.041; and A vs B, p = 0.782 resulted respectively. As for operated hemorrhoids, the time-to-stop bleeding was 3 and 4 weeks in Groups A and B and 5 in Group C. Histopathology showed an association between flavonoids and piles' fibrosis (p = 0.008). Phlebotonics in HD, as well as after surgery, showed significant beneficial effects. Flavonoids are the most effective phlebotonics against bleeding and anal irritation

    Hyperspectral and LiDAR data for the prediction via machine learning of tree species, volume and biomass: a possible contribution for updating forest management plans

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    This work intends to lay the foundations for identifying the prevailing forest types and the delineation of forest units within private forest inventories in the Autonomous Province of Trento (PAT), using currently available remote sensing solutions. In particular, data from LiDAR and hyperspectral surveys of 2014 made available by PAT were acquired and processed. Such studies are very important in the context of forest management scenarios. The method includes defining tree species ground-truth by outlining single tree crowns with polygons and labeling them. Successively two supervised machine learning classifiers, K-Nearest Neighborhood and Support Vector Machine (SVM) were used. The results show that, by setting specific hyperparameters, the SVM methodology gave the best results in classification of tree species. Biomass was estimated using canopy parameters and the Jucker equation for the above ground biomass (AGB) and that of Scrinzi for the tariff volume. Predicted values were compared with 11 field plots of fixed radius where volume and biomass were field-estimated in 2017. Results show significant coefficients of correlation: 0.94 for stem volume and 0.90 for total aboveground tree biomass

    Pulse shape discrimination of charged particles with a silicon strip detector

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    Abstract A simple and effective pulse shape discrimination technique is applied to a silicon strip detector array. Excellent charge identification from H up to the Ni projectile has been obtained and isotope separation up to N has also been observed. The method we systematically studied is essentially based on a suitable setting of the constant fraction discriminators, and its main advantage is that no additional electronic modules are needed compared to the ones used in the standard TOF technique

    Ureteroscopy in pregnant women with complicated colic pain: Is there any risk of premature labor?

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    Objective: Clinical presentation of ureteral stones during pregnancy is generally with renal colic pain. The aim of this study is to present our experience in the management of renal colic during pregnancy in emergency settings. Materials and methods: 208 pregnant patients who presented to emergency department with renal colic pain and underwent ureteroscopy (URS) due to failed conservative therapy were enrolled in the study. Urinary tract stones were diagnosed either with ultrasound (US) examination or during URS. Laser lithotripsy and double J (DJ) stent placement were routinely done in all patients with ureteral stones. The incidence of infective complications and premature uterine contractions (PUC) due to URS were compared. Results: No stone was identified in 36.1% (n = 75) of patients with using US and diagnostic URS. Of the remaining 133 patients, 30 (22.6%) had no stone at US but stones were diagnosed during diagnostic URS. The type of anesthesia had no significant effect on PUC. An increased risk of sepsis and PUC was found in patients with fever at the initial presentation. Interestingly, PUC was more frequent in patients with lower serum magnesium levels. There was a significant correlation with time delay until the intervention and the risk of urosepsis and PUC, individually. Conclusions: Ureteroscopy is a safe option for evaluation of pregnant patients with unresolved renal colic. According to the current findings, timing of the operation is the most important factor affecting the septic risks and abortion threat. Surgical intervention with URS must be planned as soon as possible

    D3.1 - Architettura dell'infrastruttura 3DLab-Sicilia e del "liquid lab"

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    Questo documento definisce due elementi fondamentali per il Progetto 3DLab-Sicilia sui quali si costruiscono le numerose applicazioni e i casi d’uso applicativi che sono stati discussi con ampio dettaglio nel deliverable “D4.1 – Analisi dettagliata dei requisiti dei casi d’uso“. Tali elementi sono rappresentati da: l’infrastruttura del progetto, comprensiva dei relativi elementi hardware e software; il “liquid lab”. Un ulteriore punto di contatto tra il presente rapporto e il deliverable D4.1 è rappresentato dall’adozione condivisa trasversalmente della tassonomia dell’hardware e del software relativi al progetto 3DLab-Sicilia. Per la descrizione dettagliata della tassonomia in oggetto si rimanda alla Sezione 2.1 e all’Appendice 1 del deliverable D4.1. Il presente documento è organizzato come segue. La Sezione 2 tratta, insieme ad una introduzione ai contenuti e alle finalità del presente deliverable, la descrizione dello stato dell’arte delle soluzioni oggetto di analisi in queste pagine. La Sezione 3 dettaglia ad alto livello l’architettura dell’infrastruttura del progetto per la Realtà Virtuale nelle 3 sedi selezionate in 3DLab-Sicilia: Catania, presso SWING:IT; Palermo, presso lo IEMEST; e Troina (EN), presso l’IRCCS-OASI. Nella Sezione 4 la descrizione e l’analisi tecnica dell’infrastruttura sono illustrate approfonditamente, ponendo il fuoco sui diversi elementi compresi al suo interno. Sono state analizzate le caratteristiche tecniche delle VR CAVE e dei Visori per Realtà Virtuale (VR) nonché dei dispositivi per la Realtà Aumentata (AR), i laser scanner 3D per i rilievi, i droni, il videocapillaroscopio e l’archivio digitale. La Sezione 5 dettaglia, infine, gli obiettivi, l’architettura e le caratteristiche del “liquid lab” che sarà realizzato nell’ambito del progetto

    Physics case for an LHCb Upgrade II - Opportunities in flavour physics, and beyond, in the HL-LHC era

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    The LHCb Upgrade II will fully exploit the flavour-physics opportunities of the HL-LHC, and study additional physics topics that take advantage of the forward acceptance of the LHCb spectrometer. The LHCb Upgrade I will begin operation in 2020. Consolidation will occur, and modest enhancements of the Upgrade I detector will be installed, in Long Shutdown 3 of the LHC (2025) and these are discussed here. The main Upgrade II detector will be installed in long shutdown 4 of the LHC (2030) and will build on the strengths of the current LHCb experiment and the Upgrade I. It will operate at a luminosity up to 2×1034 cm−2s−1, ten times that of the Upgrade I detector. New detector components will improve the intrinsic performance of the experiment in certain key areas. An Expression Of Interest proposing Upgrade II was submitted in February 2017. The physics case for the Upgrade II is presented here in more depth. CP-violating phases will be measured with precisions unattainable at any other envisaged facility. The experiment will probe b → sl+l−and b → dl+l− transitions in both muon and electron decays in modes not accessible at Upgrade I. Minimal flavour violation will be tested with a precision measurement of the ratio of B(B0 → μ+μ−)/B(Bs → μ+μ−). Probing charm CP violation at the 10−5 level may result in its long sought discovery. Major advances in hadron spectroscopy will be possible, which will be powerful probes of low energy QCD. Upgrade II potentially will have the highest sensitivity of all the LHC experiments on the Higgs to charm-quark couplings. Generically, the new physics mass scale probed, for fixed couplings, will almost double compared with the pre-HL-LHC era; this extended reach for flavour physics is similar to that which would be achieved by the HE-LHC proposal for the energy frontier

    LHCb upgrade software and computing : technical design report

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    This document reports the Research and Development activities that are carried out in the software and computing domains in view of the upgrade of the LHCb experiment. The implementation of a full software trigger implies major changes in the core software framework, in the event data model, and in the reconstruction algorithms. The increase of the data volumes for both real and simulated datasets requires a corresponding scaling of the distributed computing infrastructure. An implementation plan in both domains is presented, together with a risk assessment analysis
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