31 research outputs found
Random, deterministic, and hybrid algorithms for distributed beamforming
Distributed beamforming is a form of cooperation among nodes in a wireless network to efficiently deliver a common message to a distant receiver. The critical requirement to achieve electromagnetic coherence is to synchronize the initial phases of all local oscillators, introducing minimal overhead and complexity. In the paper we introduce random, deterministic and hybrid algorithms, all based on feedback from the common receiver as the driving force, but with different phase update strategies. Our numerical results show that these algorithms achieve faster convergence time than previously proposed approaches
Molecular markers and QTL analysis for grain quality improvement in wheat
Molecular marker technology is playing an increasingly important role in the selection of wheat lines with improved quality attributes. This is due to the identification of molecular markers tightly linked to chromosome regions involved in the control of important quality characteristics such as dough properties, grain hardness, semolina and flour colour, grain protein content and starch composition, which strongly influence wheat end use, and its nutritional and market value. Marker assisted selection (MAS) will increase the efficiency of the breeding process, particularly when phenotyping requires laborious and time-consuming analyses, performed in advanced generations because of the relatively large amount of grain required. Moreover, the implementation of MAS allows the selection of individuals carrying the favourable alleles at the target loci, and also the pyramiding of favourable QTL alleles from different sources and for different traits. This notwithstanding, the progress obtained until now in applying MAS to quality characteristics has been slow compared to other traits
Impact of High-End Receivers in a Peer-To-Peer Cooperative Localization System
This paper introduces the concept of peer-to-peer cooperation as an aiding technique in GNSS positioning and addresses the impact of the presence of professional receivers in the network. The impact of their higher accuracy is evaluated for the cases of both GNSS-data only and hybrid data exchange. Kalman Filters are considered as the data fusion engine
Cross-Band Aided Code Acquisition in Dual-Band GNSS Receivers
none6noThe problem of fast code acquisition in dual-band Galileo
receivers is tackled. The proposed techniques exploit the Galileo
E1 and E5 Open Service signals structure, implementing a
cross-band aiding approach that yields mutual assistance in
code synchronization adopting a master/slave configuration.
The schemes are analyzed in terms of mean acquisition time
(MAT) introducing the procedure flow-graph and overall mean
acquisition time (OMAT). Numerical evaluation shows enhanced
OMAT performance w.r.t. autonomous dual-band acquisition,
guaranteeing complexity reduction.mixedL. Deambrogio; F. Bastia; C. Palestini; R. Pedone; M. Villanti; G. E. CorazzaL. Deambrogio; F. Bastia; C. Palestini; R. Pedone; M. Villanti; G. E. Corazz
Sources of resistance to diseases of sugar beet in related Beta germplasm: I. Foliar diseases
Resistance to four foliar diseases of sugar beet (Beta vulgaris ssp. vulgaris), virus yellows caused by Beet mild yellowing virus (BMYV) and Beet yellows virus (BYV), powdery mildew (Erysiphe betae) and Cercospora leaf spot (Cercospora beticola), was assessed in up to 600 accessions of closely related wild and cultivated Beta species. Most accessions were from the Section Beta, a taxon containing types most closely related to, and sexually compatible with, sugar beet and therefore most valuable for use in crop improvement. Between 1\u201312% of accessions were highly resistant (resistance scores of 642 on an international standardised resistance scale of 1\u20139) to these diseases. These levels, however, underestimate the potential number of resistant sources available from this section as some accessions with intermediate mean resistance scores contained a significant proportion of highly resistant plants within segregating populations. Variation in resistance to all diseases except BYV was observed within the Section Beta. Much higher levels of resistance were observed, and more frequently, in more distantly related sections of the genus Beta. Accessions of the Section Corollinae were highly resistant to both viruses (>62% of accessions tested), but less so to Cercospora (15%) and they were very susceptible to powdery mildew. Section Procumbentes accessions were highly resistant to BMYV and Cercospora (100%) but less so to powdery mildew (50%) and BYV (20%). However, sexual incompatibility between these sections and sugar beet make utilisation of these sources impractical using conventional breeding methods