Search results for "Telecommunication"
showing 10 items of 1769 documents
BEGIN: Big Data Enabled Energy-Efficient Vehicular Edge Computing
2018
Vehicular edge computing is essential to support future emerging multimedia-rich and delay-sensitive applications in vehicular networks. However, the massive deployment of edge computing infrastructures induces new problems including energy consumption and carbon pollution. This motivates us to develop BEGIN (Big data enabled EnerGy-efficient vehIcular edge computiNg), a programmable, scalable, and flexible framework for integrating big data analytics with vehicular edge computing. In this article, we first present a comprehensive literature review. Then the overall design principle of BEGIN is described with an emphasis on computing domain and data domain convergence. In the next section, …
How to prevent cyber-attacks in inter-vehicle communication network?
2015
In this work, we aim to secure communication in a vehicular network by providing a proactive mechanism that can detect and predict with a high accuracy the future behavior of malicious attacker. In fact, the mechanisms proposed in the literature consider only detection mechanisms and do not prevent attacks that may arise in the network. Simulation results show that our mechanism has a high detection rate, low false positive rate while generating a low communication overhead.
Toward a lightweight and efficient UAV‐aided VANET
2019
International audience; Connectivity in a smart vehicular network is quite sensitive and highly affected by its dynamic network topology. Issues related to the intermittent nature of connectivity may arise due to the high mobility of nodes and network heterogeneity. In sparse areas, a vehicular network is basically a disruption‐tolerant network suffering from frequent disconnections, long delays, and messages loss. Facing these issues, and specifically for time‐sensitive applications, Unmanned Aerial Vehicle (UAV) can provide valuable assistance to Vehicular Ad Hoc Network (VANET) by assuming a relay node role between disconnected segments in the road. In such scenarios, effective communica…
A Non-WSSUS Mobile-to-Mobile Channel Model Assuming Velocity Variations of the Mobile Stations
2017
This paper aims to characterize the effects that the velocity variations of the mobile stations (MSs) produce on the correlation properties of non-stationary time-frequency (TF) dispersive mobile- to-mobile (M2M) fading channels. Toward that end, we propose a novel geometrical model for non-wide-sense stationary uncorrelated scattering (non-WSSUS) M2M channels that incorporates such variations following a plane wave propagation approach. Capitalizing on the mathematical simplicity of this approach, we derive a general expression for the four-dimensional (4D) TF correlation function (TFCF) of the proposed channel model. From this expression, we analyze the influence of the MSs' acceleration#…
Velocity estimation in wideband mobile stations equipped with multiple antennas
2009
©2009 IEEE. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEE. Article also available from publisher: http://dx.doi.org/10.1109/VETECS.2009.5073907 A new method is proposed for estimating the velocity of wideband mobile stations (MSs) equipped with multiple antennas. The MS speed is determined using the well-known relationship between the direction-of-arrivals (DOAs) and the Doppler frequency shifts experienced by the mult…
Autonomic Nerve Blocks
1988
Selective block of the sympathetic trunk was first reported by Sellheim and, shortly thereafter, by Lawen, Kappis, and Finsterer (1905–1910). In 1924, reports were published by Brumm and Mandl and by Swertlow. After 1930, the technique and the indications were established by White in the United States and Leriche and Fontaine in Europe.
The effect of 26 versus 29-inch wheel diameter in the transmission of vibrations in cross-country mountain biking.
2021
Vibrations experienced by cyclists can affect their performance and health. We analysed the vibrations transmitted by mountain bike (26 or 29-inch wheels), in a 2,110 m circuit with a sample of 55 cyclists. The results indicate that the 29"-wheel increases speed (
Imagen técnica multi-banda en la investigación del proceso de ejecución de las pinturas. El caso del retrato de Carlos IV, de Francisco de Goya
2018
La imagen técnica multi-banda (MBTI) es ampliamente utilizada como un método eficaz para el examen de obras de arte. Aunque las diversas técnicas que lo conforman tienen una entidad propia, cuando se usan juntas proporcionan mucha más información al confrontar los diversos resultados. El objetivo principal de este trabajo es mostrar su uso en comprensión material, procedimental y creativa de un retrato del Rey Carlos IV. Más específicamente, la imagen técnica multi-banda se ha utilizado aquí para ayudar en la reconstrucción del proceso pictórico, al revelar datos relacionados con la creación y ejecución del cuadro (ductus y pinceladas, alteraciones, dibujo subyacente y primer manchado, comp…
Dynamic Packet Bundling for VoIP Transmission Over Rel'7 HSUPA with 10ms TTI Length
2007
In this paper, the system level optimization of the voice over IP transmission in the HSUPA system, configured with a 10 ms TTI length, is analyzed. The study considers the release 7 improvements to HSUPA, in terms of the DPCCH gating concept. A dynamic activated MAC layer bundling of two VoIP packets in a single frame is proposed and compared against the single packet per frame transmission by means of quasi-static system level simulations.
VoIP end-to-end performance in HSPA with packet age aided HSDPA scheduling
2008
In this paper, we present an enhanced VoIP scheduling for the high speed downlink packet access (HSDPA) in UMTS, which takes the age of the VoIP packet into account. The downlink capacity can be significantly improved by this way, especially for shorter uplink transmission delay. In order to quantify the achievable performance improvement, we present results obtained from extensive system-level uplink and downlink simulations. Inter alia, it is shown that using the proposed scheme can lead to an increase in the downlink cell capacity of up to 16%. By applying the proposed method, the downlink performance can be improved considerably while the uplink performance remains the same, which ensur…