Search results for " switching"
showing 10 items of 176 documents
PCP-DV: An End-to end Admission Control Mechanism for IP Telephony
2001
In this paper we describe a novel endpoint admission control mechanism for IP telephony:the PCP-DV which is characterized by two fundamental features. First, it does not rely on any additional procedure in internal network routers other than the capability to apply different service priority to probing and data packets. Second, the triggering mechanism for the connection admission decision is based on the analysis of the delay variation statistics over the probing flow. Numerical results for an IP telephony traffic scenario prove that 99th delay percentiles not greater than few ms per router are guaranteed even in overload conditions.
Depletion of polyubiquitin encoded by the UBI4 gene confers pleiotropic phenotype to Candida albicans cells.
2003
We have studied the roles of polyubiquitin in Candida albicans physiology. Heterologous expression of the C. albicans polyubiquitin (UBI4) gene in a ubi4 Saccharomyces cerevisiae strain suppressed the mutant phenotype (hypersensitivity to heat shock). A heterozygous strain UBI4/Deltaubi4::hisG, obtained following the ura-blaster procedure, was used to construct a conditional mutant using a pCaDis derivative plasmid. By serendipity we isolated the UBI4 conditional mutant as well as a UBI4 mutant containing a non-functional MET3 promoter. Depletion of polyubiquitin conferred pleiotropic effects to mutant cells: (i) a limited increased sensitivity to mild heat shock; (ii) increased formation o…
An analytical model of a new packet marking algorithm for TCP flows: Preliminary insights
2004
In differentiated services networks, packet marking schemes can be devised to differentiate packets belonging to a same TCP flow, with the goal of improving the experienced performance. This paper presents an analytical model for an adaptive packet marking scheme proposed in our previous work. The model combines three specific sub-models aimed at describing i) the TCP sources aggregate ii) the marker, and iii) the network status. Some preliminary simulative results seem to validate the model.
An Integrated Multi-service Software Simulation Platform: SIMPSONS Architecture
2005
This paper describes SIMPSONS (SIp and MPls Simulations On NS-2), which is a software platform for simulating multiple network scenarios, such as Telephony Over IP (TOIP), and multi-services networks extending the functionalities of Network Simulator NS-2. The innovative aspects of SIMPSONS is the complete integration of control protocols and traffic engineering mechanisms inside the same simulation tool. In fact, next generation networks must meet basically two fundamental requirements: support of Quality of Service (QoS) and Traffic Engineering (TE) functionalities. SIMPSONS is able to simulate DiffServ, MPLS, OSPF and SIP and their interaction in everything TOIP scenario. So with this po…
Anodic TiO2 in ReRAM: Influence of Si-doping on the Resistive Switching Properties of Titanium Oxide
2016
TiO2 has attracted much attention due to its potential widespread applications, including capacitors, photocatalysis, solar energy conversion and, more recently, redox-based random access memories (ReRAM). For micro and nano-electronics applications, TiO2 is usually grown through Chemical and Physical Vapour Deposition techniques, such as Atomic Layer Deposition (ALD), Pulsed Laser Deposition (PLD), Sputtering and so on. In ReRAM field, the control of oxide structure (crystallinity, defects concentration etc.) and the choice of electrodes are crucial to have resistive switching phenomena inside the oxide. Thus, anodizing can be proposed as a simple and low cost way to grow TiO2 and to tune …
Apparato di commutazione
2012
La presente invenzione si riferisce ad un apparato di commutazione per il controllo e l'impostazione della configurazione circuitale dei pannelli di un modulo fotovoltaico.
Non linear digital control improving transient response:design and test on a multiphase VRM
2010
Robust and Model Predictive Control applied to DC/DC converters and Shunt Active Filters
Al giorno d'oggi, la domanda di energia elettrica incrementa giorno per giorno. La gente spesso la usa con superficialità sottovalutando quanto essa sia preziosa. Fino a qualche decennio fa, la generazione di energia elettrica era centralizzata e dipendeva dallo sfruttamento delle risorse fossili. La limitatezza delle fonti fossili, insieme agli effetti ambientali del loro sfruttamento, hanno portato la ricerca a trovare vettori energetici alternativi poco inquinanti e facilmente reperibili. Lo sviluppo e la diffusione delle fonti energetiche rinnovabili hanno sancito la fine di una rete elettrica centralizzata a favore di una nuova idea di rete elettrica di tipo distribuita che permette di…
CONTROLLO DELLA CONVERSIONE DELL'ENERGIA ELETTRICA IN MICRORETI INTELLIGENTI
La limitatezza delle fonti fossili, insieme agli effetti ambientali del loro sfruttamento, hanno portato la ricerca a trovare fonti energetiche alternative poco inquinanti e facilmente reperibili. Lo sviluppo delle fonti rinnovabili e la crescente attenzione verso l’efficienza hanno permesso l'integrazione di un nuovo sistema di distribuzione dell’energia non più centralizzato, ma basato sulla generazione distribuita, permettendo all'occorrenza anche il funzionamento in autonomia di sottosistemi della rete comprendenti generazione locale e carichi, detti microgrid (µG). Una µG (fig.1) è quindi un insieme di carichi e sorgenti di energia operanti come un unico sistema [1] e che presenta innu…
A new perspective of innovation toward a non-contact society - Amazon's initiative in pioneering growing seamless switching
2022
This paper elucidates the inside of the black box of Amazon's unique research and development (R&D) dynamism that made it the world's top R&D leader by transforming “routine or periodic alterations” into “significant improvement” during the R&D process. This dynamism also succeeded in transforming the COVID-19 pandemic period into a springboard for new innovation, leading to Amazon's notable growth notwithstanding the pandemic. An empirical analysis using a techno-economic approach focusing on Amazon's endeavor to develop a series of advanced digital fashions (ADFs) and online-based luxury brands (neo-luxury) before and during the COVID-19 pandemic was conducted. Amazon became a global appa…