Search results for "IONT"
showing 10 items of 382 documents
The Burrows-Wheeler Transform between Data Compression and Combinatorics on Words
2013
The Burrows-Wheeler Transform (BWT) is a tool of fundamental importance in Data Compression and, recently, has found many applications well beyond its original purpose. The main goal of this paper is to highlight the mathematical and combinatorial properties on which the outstanding versatility of the $BWT$ is based, i.e. its reversibility and the clustering effect on the output. Such properties have aroused curiosity and fervent interest in the scientific world both for theoretical aspects and for practical effects. In particular, in this paper we are interested both to survey the theoretical research issues which, by taking their cue from Data Compression, have been developed in the conte…
UAV-Aided Multi-Antenna Covert Communication Against Multiple Wardens
2021
In this paper, we propose a UAV-aided covert communication scheme assisted by a multi-antenna jammer to maximize the transmission rate between a ground transmitter and a UAV receiver against several randomly distributed wardens. The transmitter adopts the maximum ratio transmission, while the jammer zero-forces its transmitted signal at the UAV to disturb the monitoring at wardens without interfering the legitimate transmission. First, we analyze the detection performance and derive the optimal threshold for each warden to minimize its detection outage probability (DOP). Then, with the worst situation in which all wardens set their respective optimal thresholds to achieve the minimum global…
Performance evaluation of the MPE-iFEC Sliding RS Encoding for DVB-H streaming services
2008
This article studies the performance of the Sliding RS Encoding (SRSE) in the transmission of streaming services in DVB-H (Digital Video Broadcasting - Transmission System for Handheld Terminals) networks. The SRSE forms part of a set of specifications called MPE-iFEC which has been recently defined in the DVB-SH (Digital Video Broadcasting - Satellite Services to Handheld Devices) standard and is fully compatible with the link layer of DVB-H. MPE-iFEC is capable of encoding information related to different datagram bursts in a jointly manner in order to counteract the long signal blockages expected in satellite reception. This is what is usually referred to as Multi-Burst Encoding (MBE) an…
The Genome of Cardinium cBtQ1 Provides Insights into Genome Reduction, Symbiont Motility, and Its Settlement in Bemisia tabaci
2014
International audience; Many insects harbor inherited bacterial endosymbionts. Although some of them are not strictly essential and are considered facultative, they can be a key to host survival under specific environmental conditions, such as parasitoid attacks, climate changes, or insecticide pressures. The whitefly Bemisia tabaci is at the top of the list of organisms inflicting agricultural damage and outbreaks, and changes in its distribution may be associated to global warming. In this work, we have sequenced and analyzed the genome of Cardinium cBtQ1, a facultative bacterial endosymbiont of B. tabaci and propose that it belongs to a new taxonomic family, which also includes Candidatu…
The genetic structure of the cosmopolitan three-partner lichenRamalina farinaceaevidences the concerted diversification of symbionts
2012
The epiphytic lichen Ramalina farinacea is distributed throughout the northern hemisphere in which the same two algal Trebouxia species (provisionally named TR1 and TR9) coexist in every thallus. Ramalina farinacea symbionts were characterized based on the two fungal nuclear loci (nrITS and rpb2 ) along with the primary and secondary structures of nrITS from each Trebouxia species in the Iberian Peninsula and Canary Islands. The results indicated a noticeable genetic differentiation between mycobionts from these two geographic areas and also suggested concerted changes in the three partners of a lichen symbiosis toward two clearly distinguishable ‘holobiont’ lineages. Modeling of ITS2 RNA s…
Understanding the dialog between the gut microbiota and the endosymbiont in the model system Blattella germanica
2020
Aquesta tesi doctoral forma part de la investigació sobre l’evolució de la simbiosi en insectes realitzada durant molts anys pel grup de Genètica Evolutiva de la Universitat de València. L’organisme model utilitzat en aquest estudi és la panerola alemanya, Blattella germanica, un insecte omnívor i cosmopolita. La panerola alemanya posseeix dos simbionts: un endosimbiont, Blattabacterium, i una microbiota intestinal complexa. La funció de l’endosimbiont ha estat proposada prèviament com a la producció de metabòlits essencials mitjançant el reciclatge del nitrogen a través de la via ureolítica. Aquesta panerola comparteix la font d’aliment i l’ambient amb els humans, cosa que podria explicar …
A DGS gesture dictionary for modelling on mobile devices
2017
ABSTRACTInteractive or Dynamic Geometry System (DGS) is a tool that help to teach and learn geometry using a computer-based interactive environment. Traditionally, the interaction with DGS is based on keyboard and mouse events where the functionalities are accessed using a menu of icons. Nevertheless, recent findings suggest that such a traditional model of interaction has a steep learning curve and is inadequate to develop DGS for devices with multi-touch screens. Thus, we propose a new interaction model for DGS based on a gesture dictionary which enables the construction and manipulation of geometric objects without the need of accessing a menu of icons. The dictionary is divided into thr…
Non-periodic Discrete-Spline Wavelets
2015
This chapter describes wavelet analysis in the spaces of discrete splines whose spans are powers of 2. This wavelet analysis is similar to wavelet analysis in the polynomial-spline spaces. The transforms are based on relations between exponential discrete splines from different resolution scales. Generators of discrete-spline wavelet spaces are described. The discrete-spline wavelet transforms generate wavelet transforms in signal space. Practically, wavelet transforms of signals are implemented by multirate filtering of signals by two-channel filter banks with the downsampling factor 2 (critically sampled filter banks). The filtering implementation is accelerated by switching to the polyph…
Statistical Modeling and Analysis of Mobile-to-Mobile Fading Channels in Cooperative Networks Under Line-of-Sight Conditions
2009
Published version of an article from the journal: Wireless Personal Communications. The original publication is available at Springerlink. http://dx.doi.org/10.1007/s11277-009-9721-4 Recently, mobile-to-mobile (M2M) cooperative network technology has gained considerable attention for its promise of enhanced system performance with increased mobility support. As this is a new research field, little is known about the statistical properties of M2M fading channels in cooperative networks. So far, M2M fading channels have mainly been modeled under the assumption of non-line-of-sight (NLOS) conditions. In this paper, we propose a new model for M2M fading channels in amplify-and-forward relay lin…
Throughput and energy efficiency comparison of one-hop, two-hop, virtual relay and cooperative retransmission schemes
2010
Paper presented at the 2010 2010 European Wireless Conference. (c) 2010 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other users, including reprinting/ republishing this material for advertising or promotional purposes, creating new collective works for resale or redistribution to servers or lists, or reuse of any copyrighted components of this work in other works. Paper also available from the publisher: http://dx.doi.org/10.1109/EW.2010.5483469 Two main types of approaches exist for implementing cooperative communications at the MAC layer: virtual-hop relay and cooperative retransmission. While the virtual-hop relay schemes employ relay n…