4,920 research outputs found
Echi della lezione di Francesco Gallo in alcuni edifici religiosi di Francesco Ottavio Magnocavalli
No full textPOST-TRAUMATIC INFECTED NECROSIS OF THE ASTRAGALUS TREATED BY TIBIOTALOCALCANEAL ARTHRODESIS: DESCRIPTION OF A CLINICAL CASE.
No full textPlanning mm-Wave Access Networks Under Obstacle Blockages: A Reliability-Aware Approach
No full textMillimeter-wave (mm-wave) technologies are the main driver to deliver the multiple-Gbps promise in next-generation wireless access networks. However, the GHz-bandwidth potential must coexist with a harsh propagation environment. While strong attenuations can be compensated by directional antenna arrays, the severe impact of obstacle blockages can only be mitigated by smart resource allocation techniques. Multi-connectivity, as multiple mm-wave links from a mobile device to different base stations, is one of them. However, the higher reliability provided by several access alternatives can be fully exploited only if uncorrelated link statuses are guaranteed. Therefore, spatial diversity must be enforced. Moreover, since interposing obstacles can block a link, short access links allow reducing the link unavailability probability. Smart base-station selections can be made once the network is deployed, however, our results show that much better results are achievable if spatial diversity and link-length aspects are directly included in the network planning phase. In this article, we propose an mm-wave access network planning framework that considers base-station spatial diversity, link lengths, and achievable user throughput, according to channel conditions and network congestion. The comparison against traditional k-coverage approaches shows that our approach can obtain much better access reliability, thus providing higher robustness to random obstacles and self-blockage phenomena
Fast Cell Discovery in mm-wave 5G Networks with Context Information
No full textThe exploitation of mm-wave bands is one of the key-enabler for 5G mobile radio networks. However, the introduction of mm-wave technologies in cellular networks is not straightforward due to harsh propagation conditions that limit the mm-wave access availability. Mm-wave technologies require high-gain antenna systems to compensate for high path loss and limited power. As a consequence, directional transmissions must be used for cell discovery and synchronization processes: this can lead to a non-negligible access delay caused by the exploration of the cell area with multiple transmissions along different directions.
The integration of mm-wave technologies and conventional wireless access networks with the objective of speeding up the cell search process requires new 5G network architectural solutions. Such architectures introduce a functional split between C-plane and U-plane, thereby guaranteeing the availability of a reliable signaling channel through conventional wireless technologies that provides the opportunity to collect useful context information from the network edge.
In this article, we leverage the context information related to user positions to improve the directional cell discovery process. We investigate fundamental trade-offs of this process and the effects of the context information accuracy on the overall system performance. We also cope with obstacle obstructions in the cell area and propose an approach based on a geo-located context database where information gathered over time is stored to guide future searches. Analytic models and numerical results are provided to validate proposed strategies
Facing the Millimeter-wave Cell Discovery Challenge in 5G Networks with Context-awareness
No full textThe introduction of mm-wave technologies in the future 5G networks poses a rich set of network access challenges. We need new ways of dealing with legacy network functionalities to fully unleash their great potential, among them the cell discovery procedure is one of the most critical. In this article, we propose novel cell discovery algorithms enhanced by the context information available through a C-/Uplane- split heterogeneous network architecture. They rely on a geo-located context database to overcome the severe effects of obstacle blockages. Moreover, we investigate the coordination problem of multiple mm-wave base stations that jointly process user access requests. We show that optimizing the resource allocated to the discovery has a great importance in defining perceived latency and supported user request rate. We have performed complete and accurate numerical simulations to provide a clear overview of the main challenging aspects. Results show that the proposed solutions have an outstanding performance with respect to basic discovery approaches and can fully enable mm-wave cell discovery in 5G networks
Francesco Ottavio Magnocavalli, un architetto dilettante tra tardobarocco e neoclassicismo. La fortuna critica e le incerte attribuzioni
No full textF.O. Magnocavalli, nobile casalese, colto letterato, tragediografo e architetto dilettante, è figura cosmopolita e multiforme dello Stato sabaudo, riscoperta in tempi relativamente recenti e con un'incerta attribuzione di molte opere, soprattutto di committenza religiosa. Il saggio, attraverso un'attenta rilettura critica delle fonti, cerca di mettere in relazione la formazione di Magnocavalli, la sua frequentazione alfieriana, i dati sugli edifici realizzati o progettat
Blockage-Robust 5G mm-Wave Access Network Planning
No full textMm-wave technologies are a promising solution to provide ultra-high capacity in 5G wireless access networks. However, the potential of several-GHz bandwidths must coexist with a harsh propagation environment. While high attenuations can be compensated by advanced antenna systems, the severe obstacle blockage effect can only be mitigated by more sophisticated network managements. One of the most widely adopted techniques to guarantee a reliable service in mm-wave access scenarios is to establish multiple connections from the mobile to the different base stations. However, the advantage of multiple mm-wave connections can be fully exploited only if uncorrelated channels are available, thus spatial diversity must be ensured. Although smart base station selections could be made once the network is deployed, much better results are achievable if high-diversity selection aspects are already included in the network planning phase. In this paper, we propose for the first time a mm-wave access network planning framework which considers both spatial diversity among potential base-station selection candidates and user achievable throughput, according to channel conditions and network congestion. The results show that our approach allows to obtain much better spatial diversity conditions than traditional k-coverage approaches, and this can indeed provide higher robustness in presence of sudden obstacles
Le lettere a Montesquieu: Govone nel contesto della cultura europea dell'Illuminismo
No full textUna profonda e sincera amicizia – attestata nella corrispondenza dall’uso di espressioni esplicitamente familiari e vezzeggiative
(«mon cher ami» e ancora «je vous embrasse avec la plus tendre et la plus vive amitié») – contrassegna i rapporti tra Charles-Louis de Secondat, barone di La Brède e di Montesquieu (noto in ambito internazionale semplicemente come «Mr. de Montesquieu») e i due figli del potente conte di Govone, Ottavio Francesco Solaro, primo scudiero della regina Anna Maria d’Orléans, diplomatico e poi ministro di Stato di Vittorio Amedeo II, ossia il marchese di Breglio Giuseppe Roberto Solaro
(1680-1764), cavaliere della Santissima Annunziata, ambasciatore a Vienna e poi ministro di Stato sotto Carlo Emanuele III, e il Gran Priore della Lingua di Lombardia dell’Ordine Gerosolimitano o di Malta Antonio Maurizio Solaro (1689-1762), detto da Montesquieu le Commendateur de Solar, ambasciatore del re di Sardegna a Vienna e a Parigi e poi ambasciatore di Malta a Roma. Ma la corrispondenza getta luce anche sui rispettivi cantieri di La Brède e di Govone, descrivendone le trasformazioni e i gusti dei committenti
Il territorio come un giardino: immagini di paesaggio da cabrei di estesi possedimenti terrieri piemontesi
No full textIl saggio esplora il concetto di "paesaggio del privilegio", inteso come spazio - in genere appartenente appunto a un Ordine cavalleresco e dinastico (in questo casa la Sacra Religione dei Santi Maurizio e Lazzaro) - che per la sua natura specifica (ancora in questo caso commendatizia) sfugge alle logiche "ordinarie" a cominciare dalla catastazione e di afferma come "terra altra". L'enorme estensione di questo genere di patrimonio nel contesto piemontese si affianca alla redazione di cabrei ossia libri figurati, spesso quasi miniature anche in considerazione del loro valore encomiastico, che regalo l'immagine, per ampie aree territoriali, di un vero e proprio giardino nel paesaggio. Il saggio è offerto nel volume che amici e allievi dedicano a Vincenzo Cazzato
Intorno a Leonardo: collezioni e divagazioni in mostra
No full textLa breve prefazione spiega le ragioni delle scelte operate nell'ambito della mostra, nel contesto più ampio delle attività torinesi per le celebrazioni del cinquecentenario della morte di Leonardo da Vinci, mettendo in luce l'apporto delle singole discipline e dei componenti del gruppo di ricerca nella selezione dei temi e degli oggetti da esporre
- …
