7 research outputs found
Intent-based management and orchestration of heterogeneous openflow/IoT SDN domains
One of the main challenges in delivering end-toend service chains across multiple Software Defined Networking (SDN) and Network Function Virtualization (NFV) domains is to achieve unified management and orchestration functions. A very critical aspect is the definition of an open, vendoragnostic, and interoperable northbound interface (NBI) that should be as abstracted as possible from domain-specific data and control plane technologies. In this paper we propose a reference architecture and an intent-based NBI for end-to-end service orchestration across multiple technological domains. In particular, we consider the use case of an Internet of Things (IoT) infrastructure deployment and the corresponding cloudbased data collection, processing, and publishing services with quality differentiation.We also report the experimental validation of the proposed architecture over a heterogeneous OpenFlow/IoT SDN test bed
Software Defined Networking for The Internet of Things
Quello delle reti di sensori radio Ăš ad oggi, nel mondo delle telecomunicazioni, uno dei campi che sta crescendo e si sta sviluppando piĂč velocemente, essendo uno dei punti cardine della visione dellâInternet of Things (IoT). La natura di questo tipo di reti, costituite il piĂč delle volte da dispositivi semplici e a basso costo, che devono essere in grado di svolgere diversi tipi di applicazioni nonostante la potenza di calcolo limitata, porta alla necessitĂ di un protocollo di rete che sia allo stesso tempo flessibile e di bassa complessitĂ . Inoltre, la futura quinta generazione di reti cellulari (5G) dovrĂ inglobare anche il traffico dovuto alla reti IoT, con il prerequisito di una latenza che sia bassa e deterministica, ed il tutto tramite un approccio centralizzato. Dato questo scenario, lâapplicazione del concetto di Software Defined Networking allâinterno delle reti di sensori radio potrebbe essere una possibile soluzione alle sfide del 5G, e questa dissertazione presenta unâimplementazione di tale principio.
In particolare, questa tesi descrive la struttura di una rete IoT basata su SDN, con alcuni dei servizi addizionali che questa puĂČ fornire rispetto ad altre soluzioni per reti di sensori, come Ăš stata implementata, ed i risultati ottenuti tramite i test effettuati
High Efficiency Hybrid Radiant and Heat Pump Heating Plants for Industrial Buildings: An Energy Analysis
Innovative Hybrid Condensing Radiant System for Industrial Heating: An Energy and Economic Analysis
In this paper, an innovative hybrid condensing radiant tubes heating system for an industrial building is modelled in three climatic zones of Italy using dynamic simulation software. Radiant tubes are coupled with an airâwater heat pump, the latter serving an air heating system with terminals located in the building. The energy performance of the hybrid heating system is optimized by evaluating the best nominal power of the heat pump, the cut-off temperature in a bivalent parallel operation, the bivalent temperature in a bivalent alternative operation, and the peak power of the photovoltaic system on the roof of the building. Energy savings between 40% and 80% are calculated with respect to traditional heating systems, considering the different configurations of the system and the climates. An economic analysis also allows the evaluation of the economic advantages of this hybrid heating system for industrial buildings
First low-frequency Einstein@Home all-sky search for continuous gravitational waves in Advanced LIGO data
International audienceWe report results of a deep all-sky search for periodic gravitational waves from isolated neutron stars in data from the first Advanced LIGO observing run. This search investigates the low frequency range of Advanced LIGO data, between 20 and 100Â Hz, much of which was not explored in initial LIGO. The search was made possible by the computing power provided by the volunteers of the Einstein@Home project. We find no significant signal candidate and set the most stringent upper limits to date on the amplitude of gravitational wave signals from the target population, corresponding to a sensitivity depth of 48.7ââ[1/Hz]. At the frequency of best strain sensitivity, near 100Â Hz, we set 90% confidence upper limits of 1.8Ă10-25. At the low end of our frequency range, 20Â Hz, we achieve upper limits of 3.9Ă10-24. At 55Â Hz we can exclude sources with ellipticities greater than 10-5 within 100Â pc of Earth with fiducial value of the principal moment of inertia of 1038ââkgâm2
Search for intermediate mass black hole binaries in the first observing run of Advanced LIGO
International audienceDuring their first observational run, the two Advanced LIGO detectors attained an unprecedented sensitivity, resulting in the first direct detections of gravitational-wave signals produced by stellar-mass binary black hole systems. This paper reports on an all-sky search for gravitational waves (GWs) from merging intermediate mass black hole binaries (IMBHBs). The combined results from two independent search techniques were used in this study: the first employs a matched-filter algorithm that uses a bank of filters covering the GW signal parameter space, while the second is a generic search for GW transients (bursts). No GWs from IMBHBs were detected; therefore, we constrain the rate of several classes of IMBHB mergers. The most stringent limit is obtained for black holes of individual mass 100ââMâ, with spins aligned with the binary orbital angular momentum. For such systems, the merger rate is constrained to be less than 0.93ââGpcâ3âyrâ1 in comoving units at the 90%Â confidence level, an improvement of nearly 2 orders of magnitude over previous upper limits