LVMM: The Localized Vehicular Multicast Middleware - a Framework for Ad Hoc Inter-Vehicles Multicast Communications

This thesis defines a novel semantic for multicast in vehicular ad hoc networks (VANETs) and it defines a middleware, the Localized Vehicular Multicast Middleware (LVMM) that enables minimum cost, source-based multicast communications in VANETs. The middleware provides support to find vehicles suitable to sustain multicast communications, to maintain multicast groups, and to execute a multicast routing protocol, the Vehicular Multicast Routing Protocol (VMRP), that delivers messages of multicast applications to all the recipients utilizing a loop-free, minimum cost path from each source to all the recipients. LVMM does not require a vehicle to know all other members: only knowledge of directly reachable nodes is required to perform the source-based routing

Supplement: "Localization and broadband follow-up of the gravitational-wave transient GW150914" (2016, ApJL, 826, L13)

This Supplement provides supporting material for Abbott et al. (2016a). We briefly summarize past electromagnetic (EM) follow-up efforts as well as the organization and policy of the current EM follow-up program. We compare the four probability sky maps produced for the gravitational-wave transient GW150914, and provide additional details of the EM follow-up observations that were performed in the different bands

The population of merging compact binaries inferred using gravitational waves through GWTC-3

We report on the population properties of 76 compact binary mergers detected with gravitational waves below a false alarm rate of 1 per year through GWTC-3. The catalog contains three classes of binary mergers: BBH, BNS, and NSBH mergers. We infer the BNS merger rate to be between 10 $\rm{Gpc^{-3} yr^{-1}}$ and 1700 $\rm{Gpc^{-3} yr^{-1}}$ and the NSBH merger rate to be between 7.8 $\rm{Gpc^{-3}\, yr^{-1}}$ and 140 $\rm{Gpc^{-3} yr^{-1}}$ , assuming a constant rate density versus comoving volume and taking the union of 90% credible intervals for methods used in this work. Accounting for the BBH merger rate to evolve with redshift, we find the BBH merger rate to be between 17.9 $\rm{Gpc^{-3}\, yr^{-1}}$ and 44 $\rm{Gpc^{-3}\, yr^{-1}}$ at a fiducial redshift (z=0.2). We obtain a broad neutron star mass distribution extending from $1.2^{+0.1}_{-0.2} M_\odot$ to $2.0^{+0.3}_{-0.3} M_\odot$. We can confidently identify a rapid decrease in merger rate versus component mass between neutron star-like masses and black-hole-like masses, but there is no evidence that the merger rate increases again before 10 $M_\odot$. We also find the BBH mass distribution has localized over- and under-densities relative to a power law distribution. While we continue to find the mass distribution of a binary's more massive component strongly decreases as a function of primary mass, we observe no evidence of a strongly suppressed merger rate above $\sim 60 M_\odot$. The rate of BBH mergers is observed to increase with redshift at a rate proportional to $(1+z)^{\kappa}$ with $\kappa = 2.9^{+1.7}_{-1.8}$ for $z\lesssim 1$. Observed black hole spins are small, with half of spin magnitudes below $\chi_i \simeq 0.25$. We observe evidence of negative aligned spins in the population, and an increase in spin magnitude for systems with more unequal mass ratio

Analisi CFD di un elicottero radiocomandato

La presente tesi di Laurea è volta all’analisi CFD (Computational Fluid Dynamics) di un elicottero radiocomandato, prestando particolare attenzione allo studio delle forze che si creano sul corpo e l’interferenza generata dal rotore dell’elicottero. Si eseguono alcune simulazioni ipotizzando sempre una condizione di hovering. Il software utilizzato è STAR-CMM+ 5.02. con cui si studiano varie condizioni del flusso e varie geometrie . Si parte da una geometria semplificata (senza il rotore) sulla quale è effettuata un’ analisi di sensibilità alla griglia di calcolo delle forze, successivamente si sceglie un modello fisico stazionario, in cui la geometria del rotore risulta semplificata ed è comparabile a una superfice. Per le successive simulazioni è considerata la geometria dell’elicottero nel suo insieme eseguendo delle prove con un modello fisico stazionario e uno non stazionario. Dalle simulazioni effettuate si ottiene una stima dell’interferenza generata dal corpo dell’elicottero al flusso del rotore sia in caso idealizzato che reale

The Localized Vehicular Multicast Middleware: a Framework for Ad Hoc Inter-Vehicles Multicast Communications

This paper defines a novel semantic for multicast in vehicular ad hoc networks (VANETs) and it defines a middleware, the Localized Vehicular Multicast Middleware (LVMM) that enables minimum cost, source-based multicast communications in VANETs. The middleware provides support to find vehicles suitable to sustain multicast communications, to maintain multicast groups, and to execute a multicast routing protocol, the Vehicular Multicast Routing Protocol (VMRP), that delivers messages of multicast applications to all the recipients utilizing a loop-free, minimum cost path from each source to all the recipients. LVMM does not require a vehicle to know all other members: only knowledge of directly reachable nodes is required to perform the source-based routing

A New Gaze-BCI-Driven Control of an Upper Limb Exoskeleton for Rehabilitation in Real-World Tasks

This paper proposes a new multimodal architecture for gaze-independent brain-computer interface (BCI)-driven control of a robotic upper limb exoskeleton for stroke rehabilitation to provide active assistance in the execution of reaching tasks in a real setting scenario. At the level of action plan, the patient's intention is decoded by means of an active vision system, through the combination of a Kinect-based vision system, which can online robustly identify and track 3-D objects, and an eye-tracking system for objects selection. At the level of action generation, a BCI is used to control the patient's intention to move his/her own arm, on the basis of brain activity analyzed during motor imagery. The main kinematic parameters of the reaching movement (i.e., speed, acceleration, and jerk) assisted by the robot are modulated by the output of the BCI classifier so that the robot-assisted movement is performed under a continuous control of patient's brain activity. The system was experimentally evaluated in a group of three healthy volunteers and four chronic stroke patients. Experimental results show that all subjects were able to operate the exoskeleton movement by BCI with a classification error rate of 89.4±5.0% in the robot-assisted condition, with no difference of the performance observed in stroke patients compared with healthy subjects. This indicates the high potential of the proposed gaze-BCI-driven robotic assistance for neurorehabilitation of patients with motor impairments after stroke since the earliest phase of recover

A sub-150-nanometre-thick and ultraconformable solution-processed all-organic transistor

: Recent advancements in the field of electronics have paved the way to the development of new applications, such as tattoo electronics, where the employment of ultraconformable devices is required, typically achievable with a significant reduction in their total thickness. Organic materials can be considered enablers, owing to the possibility of depositing films with thicknesses at the nanometric scale, even from solution. However, available processes do not allow obtaining devices with thicknesses below hundreds of nanometres, thus setting a limit. Here, we show an all-organic field effect transistor that is less than 150 nm thick and that is fabricated through a fully solution-based approach. Such unprecedented thickness permits the device to conformally adhere onto nonplanar surfaces, such as human skin, and to be bent to a radius lower than 1 μm, thereby overcoming another limitation for field-effect transistors and representing a fundamental advancement in the field of ultrathin and tattoo electronics

Lower limb deep vein thrombosis in COVID-19 patients admitted to intermediate care respiratory units

COVID-19 has been associated with an increased risk of thrombotic events; however, the reported incidence of deep vein thrombosis varies depending, at least in part, on the severity of the disease. Aim of this prospective, multicenter, observational study was to investigate the incidence of lower limb deep vein thrombosis as assessed by compression ultrasound in consecutive patients admitted to three pulmonary medicine wards designated to care for patients with COVID-19 related pneumonia, with or without respiratory failure but not requiring admission to an intensive care unit. Consecutive patients admitted between March 27 and May 6, 2020 were enrolled. Patients were excluded if they were less than 18-year-old or if compression ultrasound could not be performed for any reason. Patients were assessed at admission (t0) and after 7 days (t1). Major and non-major clinically relevant bleedings were recorded. Sixty-eight patients were enrolled. Two were excluded due to anatomical abnormalities that prevented compression ultrasound; sixty patients were retested at (t1). All patients were started on antithrombotic prophylaxis, unless therapeutic anticoagulation was required. Deep vein thrombosis as assessed by compression ultrasound was observed in 2 patients (3%); one of them was later deemed to represent a previous episode. No new episodes were detected at t1. One major and 2 non-major clinically relevant bleedings were observed. In the setting of patients with COVID-related pneumonia not requiring admission to an intensive care unit, the incidence of deep vein thrombosis is low and our data support not screening asymptomatic patients

Top-down and bottom-up nanofabrication for multipurpose applications

In this article we will show three recent examples of combined strategies aiming at merging top-down and bottom-up approach for nanofabrication at nanoscale level. The first example shows the fabrication of nanogaps performed by Focus Ion Beam technique that have been used to measure the conducivity of few gold nanoparticles aggregates deposited by Dip Pen lithography. The second example deals with the parallel replica of high resolution master generated by Electron Beam Lithography by means of an innovative lithographic process based on DNA supramolecular nano-stamping. The latter example proposes the possibility to generate, through radiation exposure, direct patterning of hybrid sol-gel material doped with fluorescent molecules. The outline of the fabrication approaches and their scientifical and technical perspective are discussed