210,396 research outputs found
Link stability estimation based on link connectivity changes in mobile ad-hoc networks
No full textDear Wang,
Re: Link Stability Estimation Based on Link Connectivity Changes in Mobile Ad-hoc Networks
I have not been able to assess if this is an author version peer-reviewed or is it an author version non peer reviewed. Could you please clarify this so I can proceed to add your paper to Spiral. Spiral digital repository only accept peer-reviewed papers.
30/11/12 author has confirmed peer reviewe
Analyse de la tolérance des populations locales de fève (Vicia faba L.) à la sécheresse au stade juvénile
No full textDrought is the most important abiotic stress responsible of the production instability and lower levels of yields of faba bean (Vicia faba L.). The cropping of tolerant varieties can be an opportunity to stabilize production. The objective of the present study was to evaluate the genetic variability and to study the drought tolerance in the juvenile plant stage in a collection of local Moroccan faba bean populations from the province of Taounate. A number of 60 local populations were studied under controlled conditions in a greenhouse. Different morphological and physiological traits were studied before and under water stress and during the recovery phase. The difference between recovery and water stress phases estimates the capacity of local populations to recover from drought. The local populations contain a wide diversity for different studied traits. The gain in dry matter has a negative and highly significant correlation with dry matter yield under water stress (r = -0.64 **). The populations 16, 47, 1 and 9 have proven to be the most drought tolerant at juvenile stage
An assessment of measurements and modeling of turbulent fluxes over snow by eddy covariance at two complex mountain sites /by Michele L. Reba.
No full textSnow is a major component of the annual water balance in many locations across the globe, including the mountainous regions of the interior western U.S. and Canada. As water is scarce and over-allocated in many parts of this region, it is of the utmost importance to accurately model the amount and timing of spring runoff. Most components of snow cover energy and mass balance models are validated through direct measurements such as snow water equivalent, density, temperature, and net radiation. However, validation data for turbulent fluxes are generally limited. Eddy covariance (EC) is the most direct method to measure turbulent fluxes. Findings from this research are based on EC and meteorological measurements from two mountain sites, a wind-exposed and a sheltered sub-canopy, during the 2004, 2005, and 2006 snow seasons.;EC systems have been used successfully over snow in mountain regions but detailed analysis of post-processing and data quality is lacking. The first component of this research focuses on the viability of EC technology over snow in mountainous terrain and makes a detailed analysis of data quality and the influence post-processing has on turbulent fluxes. Post-processing and data quality analysis of these data indicate that application of EC-technology at these sites was viable and data quality parameters were comparable to other reported eddy flux research.;As detailed analysis of site characteristics on EC measurements over snow is limited, this research then generalizes findings at two contrasting sites and highlights the challenges of measuring EC over snow. The exposed site yielded measured sensible and latent heat fluxes that were respectively five and two times the magnitude of those at the sheltered site. There was less inter-annual variability in EC-measured turbulent fluxes at the sheltered compared to the exposed site. Differences between sites are explored at seasonal, monthly and event based temporal scales. These findings highlight the importance of careful review of over-snow EC-measured fluxes and the meteorological conditions during which those measurements were conducted.;Improved modeling of the snow cover that is based on physical processes instead of on empirical relationships between climate and snowcover dynamics should better predict responses to climatic variability and trends. Measured turbulent fluxes are used to determine key model parameters and update the stability functions of an existing snow cover and energy balance model to improve simulated latent heat flux while retaining accuracy in simulating snow water equivalent. The adjustable parameters of roughness length and active layer depth influenced the accuracy with which the model simulated mass and latent heat flux. At the exposed site shorter roughness lengths and a thicker active layer was optimal, while longer roughness lengths and a thinner active layer was optimal at the sheltered site. These outcomes are related to the site characteristics and can be readily incorporated into a distributed snowmelt model.Thesis (Ph. D., Civil Engineering)--University of Idaho, December 2008
An initial exploration of the link relationship between UK university Web sites.
No full textAggregates of links are of interest to information scientists in the same way as citation counts are: as potential sources of data from which new knowledge can be mined. Builds on the recent discovery of a correlation between a Web link count measure and the research quality of British universities by applying a range of multivariate statistical techniques to counts of links between pairs of universities. This represents an initial attempt at developing an understanding of this phenomenon. Extracts plausible results. Also identifies outliers in the data by the techniques, some of which were verified by being tracked down to identifiable Web phenomena. This is an important outcome because successful anomaly identification is a precondition to more effective analysis of this kind of data. The identification of groupings is encouraging evidence that Web links between universities can be mined for significant results, although it is clear that more methodological development is needed, if any but the simplest patterns are to be extracted. Finally, based upon the types of patterns extracted, argues that none of the methods used are capable of fully analysing link structures on their own
Link Services or Link Agents?
No full textA general link service for the WWW has been used within an Electronic Libraries' project. Experience using it shows that as the links become increasingly interesting to the user, processing them becomes increasingly expensive. Eventually textual analysis, ontological services and remote database lookups conflict with the goal of prompt delivery of documents. This paper summarizes the history of the Link Service software behind the Open Journal project together with the kind of links that it has been used to produce. Building on this work it then discusses how the paradigm, architecture and user interface of the DLS have been newly modified both in response to user feedback and also to allow more linking facilities to be added to the WWW environment. We then introduce AgentDLS, an agent-style system that offers suggestions to help the user's browsing and information discovery activities
Postcard from Carl W. Link to Ralph L. Cheney ( June 19,1917)
No full textA postcard from Carl W. Link to Ralph L. Cheney, dated June 19th, 1917. The front of the postcard has a picture of four men on a tennis court with tennis equipment behind them. On the back, Link tells Cheney the names of the men pictured and the team and members' happenings. He also writes that he is working at the Camp Photo with O.G. Wiseman.Ralph L. Cheney served as the head of Springfield College’s Secretarial Department from 1907 to 1924. Before taking this position, he worked as a YMCA secretary in Albany and Niagara Falls, New York
Region specific breeding for organic conditions in winter and spring faba bean (Vicia faba L.)
No full textGenetic diversity among North African faba bean landraces for competitive ability against weeds
No full textDie genetische Diversität marokkanischer Ackerbohnen (Vicia faba L.) sollte zur Verbesserung der Konkurrenzkraft von Ackerbohnen gegen Unkraut genutzt werden. Das Ziel dieser Arbeit war die detaillierte Evaluierung der Konkurrenzkraft und Produktivität einer Sammlung marokkanischer Ackerbohnen-Landrassen gegenüber dem Modellunkraut Sinapis alba. Sechzig marokkanische Ackerbohnen-Landrassen und zwei Standards wurden 2011 und 2013 auf Kornertrag und weitere agronomische Merkmale untersucht, mit und ohne Modellunkraut, in einer Spaltanlage unter Feldbedingungen an zwei Orten im Nordwesten Marokkos. Die Landrassen zeigten signifikante genetische Variation für Produktivität und Konkurrenzkraft. Mehrere Landrassen erreichten höhere Werte als die Standards. Der Ertragsverlust durch den Unkrautstress betrug im Mittel 69%, der Unkraut-Konkurrenz-Index betrug im Mittel rund 1,28. Die Landrassen × Unkraut-Interaktion für Ertrag war eine hoch signifikante und bedeutende Variationsursache. Einige Landrassen kombinierten eine hohe Konkurrenzkraft gegen das Modellunkraut mit überlegener Produktivität.The genetic diversity of Moroccan faba bean (Vicia faba L.) landraces should be exploited to improve the competitive ability of faba beans against weeds. The objective of this study was to in-detail evaluate competitive ability and productivity of a collection of Moroccan faba bean landraces relative to a model weed, Sinapis alba. Sixty Moroccan faba bean landraces and two checks were evaluated in 2011 and 2013 for grain yield and further agronomic traits, with and without model weed stress, under field conditions at two locations in the northwest of Morocco, using a split-plot design. The landraces showed significant genetic variation for productivity and competitive ability. Several landraces exhibited higher values compared to the two checks. Yield loss attributable to weed stress was, on average, about 69%; the weed competitive index was, on average, about 1.28. Landraces × weed treatment interaction for yield was a highly significant and marked source of variation. Several landraces were found to combine high levels of both, competitive ability against the model weed and productivity
Reverse-Link Performance of Synchronous DS-CDMA Systems in Dispersive Rician Multipath Fading Channels
No full textThe reverse-link performance of synchronous DS-CDMA is investigated in Rician multipath fading environments. The numerical results show that the performance benefits of synchronous transmission depend on the specular path’s power as well as on the multipath intensity decay factor of the channel. The achievable bit-error-rate reduction may become as high as an order of magnitude in comparison to the corresponding asynchronous system
Quantitative genetic analysis of embryo heterosis in faba bean (Vicia faba L.)
No full textSeeds, i.e. embryos, may be genetically different from either of their parents and moreover may express their own heterosis. The objective was to genetically analyse embryo heterosis for their own weight (i.e. seed weight) in comparison with their seedlings' heterosis, taking the large-seeded crop (Vicia faba L.) as model. A specific diallel mating scheme was used, based on four parental lines, creating 76 seed genotypes in generations P, F(1), F(2) and BC. Mature seed weight was assessed for these embryo genotypes in 3 years at one German location, and young plant biomass yield of seedlings emerging from these seeds in two greenhouse experiments. The quantitative genetic analysis showed an average of 10.6% mid-parent heterosis for mature seed weight and 14.5% mid-parent heterosis for juvenile biomass. In both traits, the embryos contributed markedly and significantly via their own genes to the genetic variation. For mature embryo weight heterosis, apparently the parental difference in seed weight was decisive, whereas for juvenile biomass heterosis, genetic unrelatedness of parents had priority.DFG [SPP1149
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