State-of-the-Art Multihoming Protocols and Support for Android

Il traguardo più importante per la connettività wireless del futuro sarà sfruttare appieno le potenzialità offerte da tutte le interfacce di rete dei dispositivi mobili. Per questo motivo con ogni probabilità il multihoming sarà un requisito obbligatorio per quelle applicazioni che puntano a fornire la migliore esperienza utente nel loro utilizzo. Sinteticamente è possibile definire il multihoming come quel processo complesso per cui un end-host o un end-site ha molteplici punti di aggancio alla rete. Nella pratica, tuttavia, il multihoming si è rivelato difficile da implementare e ancor di più da ottimizzare. Ad oggi infatti, il multihoming è lontano dall’essere considerato una feature standard nel network deployment nonostante anni di ricerche e di sviluppo nel settore, poiché il relativo supporto da parte dei protocolli è quasi sempre del tutto inadeguato. Naturalmente anche per Android in quanto piattaforma mobile più usata al mondo, è di fondamentale importanza supportare il multihoming per ampliare lo spettro delle funzionalità offerte ai propri utenti. Dunque alla luce di ciò, in questa tesi espongo lo stato dell’arte del supporto al multihoming in Android mettendo a confronto diversi protocolli di rete e testando la soluzione che sembra essere in assoluto la più promettente: LISP. Esaminato lo stato dell’arte dei protocolli con supporto al multihoming e l’architettura software di LISPmob per Android, l’obiettivo operativo principale di questa ricerca è duplice: a) testare il roaming seamless tra le varie interfacce di rete di un dispositivo Android, il che è appunto uno degli obiettivi del multihoming, attraverso LISPmob; e b) effettuare un ampio numero di test al fine di ottenere attraverso dati sperimentali alcuni importanti parametri relativi alle performance di LISP per capire quanto è realistica la possibilità da parte dell’utente finale di usarlo come efficace soluzione multihoming

Analisi e modifiche della booster pump 600DD56 Termomeccanica dell'impianto di Shoaiba Mina

Il presente lavoro di tesi è stato svolto durante un’attività di stage semestrale presso l’azienda TM.P Termomeccanica Pompe S.p.A. di La Spezia, e ha avuto come oggetto l’ottimizzazione di una pompa centrifuga e dell’impianto a essa collegato. L’attività è stata articolata in tre fasi principali, non necessariamente cronologicamente sequenziali: una fase di studio, per comprendere l’influenza delle principali grandezze sul funzionamento di una pompa e per ricercare e sviluppare nuove soluzioni; una fase di modellazione al computer, con software CAD, FEM e CFD, per sviluppare le soluzioni studiate e verificarne la funzionalità; una fase di prove pratiche, sostenute presso il centro prove aziendale, per rilevare le curve caratteristiche della macchina e misurarne tutte le prestazioni. Il progetto ha previsto innanzi tutto lo studio delle condizioni attuali della macchina, della girante, della borsa di aspirazione e delle tubazioni di ingresso alla pompa. Dopo aver rilevato le principali problematiche tramite modellazione CAD e analisi CFD, sono state studiate e verificate alcune modifiche da apportare alle principali componenti della macchina, nel rispetto delle specifiche richieste dal cliente

Chapter Introduction

At the forefront of current digital literacy studies in education, this Handbook uniquely systematizes emerging interdisciplinary themes, new knowledge, and insightful theoretical contributions to the field. The chapter topics identified through academic conference networks, rigorous analysis, and database searches of trending themes are organized in five thematic sections: Digital Futures; Digital Diversity; Digital Lives; Digital Spaces; Digital Ethics. This essential guide to digital writing and literacies research, with transformational ideas for educational and professional practice, will enable researchers to position their studies in the field and to generate new themes of inquiry

Assembling “Digital Literacies”: Contingent Pasts, Possible Futures

In this article, we examine the historical emergence of the concept of “digital literacy” in education to consider how key insights from its past might be of use in addressing the ethical and political challenges now being raised by connective media and mobile technologies. While contemporary uses of digital literacy are broadly associated with access, evaluation, curation, and production of information in digital environments, we trace the concept’s genealogy to a time before this tentative agreement was reached—when diverse scholarly lineages (e.g., computer literacy, information literacy, media literacy) were competing to shape the educational agenda for emerging communication technologies. Using assemblage theory, we map those meanings that have persisted in our present articulations of digital literacy, as well as those that were abandoned along the way. We demonstrate that our inherited conceptions of digital literacy have prioritized the interplay of users, devices, and content over earlier concerns about technical infrastructures and socio-economic relations. This legacy, we argue, contributes to digital literacy’s inadequacies in addressing contemporary dilemmas related to surveillance, control, and profit motives in connective environments. We propose a multidimensional framework for understanding digital literacies that works to reintegrate some of these earlier concerns and conclude by considering how such an orientation might open pathways for education research and practice

Large modulation of the Shubnikov-de Haas oscillations by the Rashba interaction at the LaAlO3_{3}/SrTiO3_{3} interface

We investigate the 2-dimensional Fermi surface of high-mobility LaAlO$_3$/SrTiO$_3$ interfaces using Shubnikov-de Haas oscillations. Our analysis of the oscillation pattern underscores the key role played by the Rashba spin-orbit interaction brought about by the breaking of inversion symmetry, as well as the dominant contribution of the heavy $d_{xz}$/$d_{yz}$ orbitals on electrical transport. We furthermore bring into light the complex evolution of the oscillations with the carrier density, which is tuned by the field effect

Introduction : Digital diversity, ideology, and the politics of a writing revolution

This chapter outlines some key theoretical directions important for studying writing and literacies in digital cultures. Digital Futures articulates new perspectives concerning the ethical, sensorial, and critical elements of writing and literacies, and contemporary debates at the nexus of literacies and digital rhetoric that have direct relevance to the social construction of authorial identities for youth and other writers in education contexts. Digital Diversity brings together the work of scholars from around the world to address issues of inclusion in contemporary writing and literacies research, from race to gender, and to the geographical displacement of refugees. Digital Spaces shifts the focus to social spaces that discursively shape, and which are shaped by, writing and literacies practices. Digital Ethics debates current ethical concerns associated with the social and ethical risks of children and young people's access to information on the Internet

Direct transition from quantum escape to phase diffusion regime in YBaCuO biepitaxial Josephson Junctions

Dissipation encodes interaction of a quantum system with the environment and regulates the activation regimes of a Brownian particle. We have engineered grain boundary biepitaxial YBaCuO junctions to drive a direct transition from quantum activated running state to phase diffusion regime. The cross-over to the quantum regime is tuned by the magnetic field and dissipation is encoded in a fully consistent set of junction parameters. To unravel phase dynamics in moderately damped systems is of general interest for advances in the comprehension of retrapping phenomena and in view of quantum hybrid technology

Expanding community : youth, social networking and schools

Inspiradas por las nociones de comunidad del filósofo Jean-Luc Nancy, nuestro estudio examina el concepto de comunidad y su desarrollo en entornos virtuales a través de un análisis cualitativo de la participación de alumnos de educación secundaria obligatoria (de 11 a 14 años de edad) en una red social privada. Nuestros datos indican que los alumnos, a pesar de no conocerse previamente, estaban dispuestos a conocerse y relacionarse, y a utilizar recursos de una red social privada para desarrollar la confianza necesaria para mantener sus amistades virtuales. Para lograrlo, los estudiantes usaron dos métodos de interrelación que llamamos «trabajo público» y «trabajo de proximidad». Al negociar sus posiciones relativas a los otros estudiantes (trabajo de proximidad) y a través de espacios públicos y privados (trabajo público), los jóvenes utilizaron diversos instrumentos semióticos para entablar amistad y para enfrentarse a los numerosos retos de la comunicación con desconocidos a través de medios digitales. Este estudio indica que las redes sociales educativas pueden ser diseñadas con fines comunicativos y para actividades que ponen de relieve los intercambios recíprocos que son éticamente y socialmente conscientes. Por último, los resultados sugieren que, aunque históricamente han demostrado una resistencia a la innovación tecnológica, las escuelas y otras instituciones educativas tienen un papel importante que desempeñar en este procesoThis study examined the construct of community and its development in online spaces through a qualitative analysis of middle school students’ participation in a private social network. Drawing on notions of community inspired by philosopher Jean-Luc Nancy, we found that students, despite not knowing one another previously, were willing both to encounter and come to know each other, using the resources of the network to build the trust that became foundational to their online social relationships. They did so primarily through two kinds of interactional effort that we call «public work» and «proximity work». Negotiating their positions relative to one another (proximity work) and across public/private spaces (public work), youth used a variety of semiotic tools to establish relationships and address the considerable challenges of digitally mediated communication with unknown others. This study suggests that educationally focused social networks can be designed for, or their uses primed toward, communicative purposes and activities foregrounding reciprocal exchange that is ethically alert and socially aware, and that schools and other educational institutions, though historically resistant to technological innovation, have an important role to play in this process