3,499 research outputs found

    Automatic best wireless network selection based on key performance indicators

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    Introducing cognitive mechanisms at the application layer may lead to the possibility of an automatic selection of the wireless network that can guarantee best perceived experience by the final user. This chapter investigates this approach based on the concept of Quality of Experience (QoE), by introducing the use of application layer parameters, namely Key Performance Indicators (KPIs). KPIs are defined for different traffic types based on experimental data. A model for an ap- plication layer cognitive engine is presented, whose goal is to identify and select, based on KPIs, the best wireless network among available ones. An experimenta- tion for the VoIP case, that foresees the use of the One-way end-to-end delay (OED) and the Mean Opinion Score (MOS) as KPIs is presented. This first implementation of the cognitive engine selects the network that, in that specific instant, offers the best QoE based on real captured data. To our knowledge, this is the first example of a cognitive engine that achieves best QoE in a context of heterogeneous wireless networks

    Impact of COVID-19 outbreak on rehabilitation services and Physical and Rehabilitation Medicine physicians' activities in Italy An official document of the Italian PRM Society (SIMFER)

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    Since the onset of the COVID-19 outbreak in Europe, Italy has been among the first affected countries, and the number of reported cases is still the highest in the continent. Since the beginning, the epidemic has had a huge impact in the acute sector of the healthcare system (especially the emergency departments, Intensive Care Units (ICUs), laboratory and imaging services), and these services have been experiencing increasing pressur

    Solitary fibrous tumor of the pleura in a 6-year-old boy

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    Evaluation of SCION for User-driven Path Control:a Usability Study

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    The UPIN (User-driven Path verification and control in Inter-domain Networks) project aims to implement a way for users of a network to control how their data is traversing it. In this paper we investigate the possibilities and limitations of SCION for user-driven path control. Exploring several aspects of the performance of a SCION network allows us to define the most efficient path to assign to a user, following specific requests. We extensively analyze multiple paths, specifically focusing on latency, bandwidth and data loss, in SCIONLab, an experimental testbed and implementation of a SCION network. We gather data on these paths and store it in a database, that we then query to select the best path to give to a user to reach a destination, following their request on performance or devices to exclude for geographical or sovereignty reasons. Results indicate our software is a viable option to offer users many paths to choose from, following a series of requests, and therefore perform user-driven path control in a SCION network.</p

    Compensatory Feto-Placental Upregulation of the Nitric Oxide System during Fetal Growth Restriction

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    Background: Fetal Growth Restriction is often associated with a feto-placental vascular dysfunction conceivably involving endothelial cells. Our study aimed to verify this pathogenic role for feto-placental endothelial cells and, coincidentally, demonstrate any abnormality in the nitric oxide system. Methods: Prenatal assessment of feto-placental vascular function was combined with measurement of nitric oxide (in the form of S-nitrosohemoglobin) and its nitrite byproduct, and of the endogenous nitric oxide synthase inhibitor asymmetric dimethylarginine. Umbilical vein endothelial cells were also harvested to determine their gene profile. The study comprised term pregnancies with normal (n = 40) or small-for-gestational-age (n = 20) newborns, small-for-gestational-age preterm pregnancies (n = 15), and bi-chorial, bi-amniotic twin pregnancies with discordant fetal growth (n = 12). Results: Umbilical blood nitrite (p<0.001) and S-nitrosohemoglobin (p = 0.02) rose with fetal growth restriction while asymmetric dimethylarginine decreased (p = 0.003). Nitrite rise coincided with an abnormal Doppler profile from umbilical arteries. Fetal growth restriction umbilical vein endothelial cells produced more nitrite and also exhibited reciprocal changes in vasodilator (upwards) and vasoconstrictor (downwards) transcripts. Elevation in blood nitrite and S-nitrosohemoglobin persisted postnatally in the fetal growth restriction offspring. Conclusion: Fetal growth restriction is typified by increased nitric oxide production during pregnancy and after birth. This response is viewed as an adaptative event to sustain placental blood flow. However, its occurrence may modify the endothelial phenotype and may ultimately represent an element of risk for cardiovascular disease in adult life.Fil: Pisaneschi, Silvia. UniversitĂ  degli Studi di Pisa; Italia. Scuola Superiore Sant’Anna; ItaliaFil: Strigini, Francesca A. L.. UniversitĂ  degli Studi di Pisa; ItaliaFil: Sanchez, Angel Matias. UniversitĂ  degli Studi di Pisa; Italia. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - Mendoza. Instituto de Medicina y BiologĂ­a Experimental de Cuyo; ArgentinaFil: Begliuomini, Silvia. UniversitĂ  degli Studi di Pisa; ItaliaFil: Casarosa, Elena. UniversitĂ  degli Studi di Pisa; ItaliaFil: Ripoli, Andrea. National Research Council. Institute of Clinical Physiology, ; ItaliaFil: Ghirri, Paolo. UniversitĂ  degli Studi di Pisa; ItaliaFil: Boldrini, Antonio. UniversitĂ  degli Studi di Pisa; ItaliaFil: Fink, Bruno. Noxygen Science Transfer and Diagnostics; AlemaniaFil: Genazzani, Andrea R.. UniversitĂ  degli Studi di Pisa; ItaliaFil: Coceani, Flavio. Scuola Superiore Sant’Anna; ItaliaFil: Simoncini, Tommaso. UniversitĂ  degli Studi di Pisa; Itali

    Comparison of semi and fully-implicit time integration schemes applied to a damage and fatigue phase field model

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    In this work, we apply semi and fully-implicit time integration schemes to the damage and fatigue phase field presented in Boldrini et al. (2016). The damage phase field is considered a continuous dynamic variable whose evolution equation is obtained by the principle of virtual power. The fatigue phase field is a continuous internal variable whose evolution equation is considered as a constitutive relation to be determined in a thermodynamically consistent way. In the semi-implicit scheme, each equation is solved separately by suited implicit method. The Newton’s method is used to linearize the equations in the fully-implicit scheme. The time integration methods are compared and the results of damage and fracture evolution under the influence of fatigue effects are presented. The computational cost associated to the semi-implicit scheme showed be lower than the fully counterpart155116CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP306182/2014-9330030172013/50238-3; 2015/10310-2; 2015/20188-
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