Search results for "LESS"
showing 10 items of 2452 documents
User requirements and resource control for cooperative multimedia applications
1997
The spread of distributed multimedia applications is setting forth a new set of challenges in the management of host and network resources for guaranteeing Quality of Service (QoS). When the multimedia applications compete for resources as in the case of a cooperative multimedia environment, the management task becomes even more difficult. In this work, we first discuss QoS for multimedia applications. We then present the architectural and implementation details of a Cooperative Multimedia Environment (CME) made up of Cooperative Multimedia Applications (COMMA), one for each user. A COMMA presents a user with a single interface that allows him to invite other users to a cooperative session,…
A Virtual Shopper Customer Assistant in Pervasive Environments
2007
In this work we propose a smart, human-like PDA-based personal shopper assistant. The system is able to understand the user needs through a spoken natural language interaction and then stores the preferences of the potential customer. Subsequently the personal shopper suggests the most suitable items and shops that match the user profile. The interaction is given by automatic speech recognition and text-to-speech technologies; localization is allowed by the use of Wireless technologies, while the interaction is performed by an Alice-based chat-bot endowed with reasoning capabilities. Besides, being implemented on a PDA, the personal shopper satisfies the user needs of mobility and it is als…
Familien og felleskapets betydning i skoleelevenes selvpresentasjoner
2017
I denne artikkelen undersoker vi hvordan norske videregaende skoleelever presenterer seg selv. Elevene har tatt med et bilde de synes er viktig til intervjuet og dette dannet utgangspunktet for en refleksjon om hva de opplever er viktig i sitt liv og i samfunnet. Problemstillingen er todelt: Hva rapporterer skoleelever som viktig i sine liv og hvordan skal vi forsta det monsteret som trer fram? Dataene antyder et kulturelt monster hvor de unge soker etter kollektiv og grupper de kan knytte seg til heller enn a frigjore seg fra. Vi spor derfor hvorvidt vi bor utvikle en tenkning om tilknytning snarere enn individualisering. ABSTRACT English title: The Importance of Family and Community in St…
An Inter-Technology Communication Scheme for WiFi/ZigBee Coexisting Networks
2017
In this paper we show how inter-technology interference can be exploited to set-up a low-rate bi-directional communication channel between heterogeneous technologies, which coexist in ISM bands. In particular, we focus on WiFi and ZigBee networks, whose high density deployments make coexistence a critical issue. We monitor the transmission duration of the interference and, after recognizing ZigBee interference from WiFi off-the-shelf receivers, we precisely measure the channel busy intervals to map time duration to communication symbols. A similar approach is used on the ZigBee receivers for making the communication channel bidirectional. Extensive experimental results show the feasibility …
Fast Secure Routing for Highly Mobile Large-Scale Ad-Hoc Vehicular Networks
2009
In highly mobile large-scale vehicular ad-hoc networks, routing protocols must be fast and efficient in terms of low routing discovery delay and communication overhead to support the applications such as car talk. Such requirement becomes more difficult to achieve when inducing security enhancement to tackle the authentication of routing messages. In this paper, we propose a lightweight (fast) secure routing protocol, Secure Proactive Tree-based Routing (SPTR) to hit these two points. SPTR makes use of the characteristics of VANET networks, that is, the traffic originates from or terminates at the gateway or road side unit. SPRT also takes advantages of certificate-less ID-based cryptograph…
Multipath extensions to the DYMO routing protocol
2007
Multipath routing is a technique that can improve performance, specially in mobile ad hoc networks. Due to traffic dispersion it can perform load balancing; minimize the energy consumed by nodes or prevent traffic analysis. In this work we focus on enhancing the DYMO protocol to support multipath routing. We study the impact of traffic dispersion on both UDP and TCP traffic when varying a set of parameters.
Simulation-based Evaluation of DMAMAC - A Dual-Mode Adaptive MAC Protocol for Process Control
2015
Control systems automation is widely used in many industrial domains and have strong requirements on delay, throughput, robustness, and reliability. In the domain of networked control systems, the medium of communication is increasingly involving wireless communication along-side conventional wired communication. Issues ranging from energy efficiency and reliability to low-bandwidth have to be addressed to enable the transition to increased use of wireless communication. In earlier work, we have proposed the Dual-Mode Adaptive MAC (DMAMAC) protocol relying on a combination of Time Division Multiple Access (TDMA) and Carrier Sense Multiple Access (CSMA). The DMAMAC protocol is able to dynami…
A Hard Look at the Neutron Stars and Accretion Disks in 4U 1636-53, GX 17+2, and 4U 1705-44 with NuStar
2017
We present $\emph{NuSTAR}$ observations of neutron star (NS) low-mass X-ray binaries: 4U 1636-53, GX 17+2, and 4U 1705-44. We observed 4U 1636-53 in the hard state, with an Eddington fraction, $F_{\mathrm{Edd}}$, of 0.01; GX 17+2 and 4U 1705-44 were in the soft state with fractions of 0.57 and 0.10, respectively. Each spectrum shows evidence for a relativistically broadened Fe K$_{\alpha}$ line. Through accretion disk reflection modeling, we constrain the radius of the inner disk in 4U 1636-53 to be $R_{in}=1.03\pm0.03$ ISCO (innermost stable circular orbit) assuming a dimensionless spin parameter $a_{*}=cJ/GM^{2}=0.0$, and $R_{in}=1.08\pm0.06$ ISCO for $a_{*}=0.3$ (errors quoted at 1 $\sig…
Hybrid QoS Based Routing for IEEE 802.16j Mesh Infrastructure
2014
Acceptance rate: 29%; International audience; With the growth of wireless networks, Wireless Mesh Network (WMN) has appeared as an emerging key solution for broadband Internet access with a low-cost deployment. Moreover, providing QoS guarantees for real-time and streaming applications such as VoIP (Voice over IP) and VoD (Video on Demand) is a challenging issue in such environment. In this paper, we propose a hybrid wireless mesh architecture to provide mesh clients with Internet access while guaranteeing QoS. It is formed by an IEEE 802.16j based infrastructure and several IEEE 802.11s based client domains. A lustering algorithm is developed to enhance scalability issues within the mesh i…
Smart Network Selection and Packet Loss Improvement during Handover in Heterogeneous Environment
2013
BEST PAPER AWARD; International audience; Seamless Handover between networks in heterogeneous environment is essential to guarantee end-to-end QoS for mobile users. A key requirement is the ability to select the next best network. Currently, the implementation of the IEEE 802.21 standard by National Institute of Standards and Technology (NIST) considers only the signal strength as a parameter to determine the best network. In this paper, we propose including additional parameters such as available bandwidth, mobile node speed and type of network during selecting a new network to improve the QoS for mobile user's application. The results of the experiments that we performed using Network Sim…