30,896 research outputs found
Exact Outage Performance Analysis of Multiuser Multi-relay Spectrum Sharing Cognitive Networks
In this paper, we investigate the outage performance of dual-hop multiuser multi-relay cognitive radio networks under spectrum sharing constraints. Using an efficient relay-destination selection scheme, the exact and asymptotic closed-form expressions for the outage probability are derived. From these expressions it is indicated that the achieved diversity order is only determined by the number of secondary user (SU) relays and destinations, and equals to M+N (where M and N are the number of destination nodes and relay nodes, respectively). Further, we find that the coding gain of the SU network will be affected by the interference threshold at the primary user (PU) receiver. Specifically, as the increases of the interference threshold, the coding gain of the considered network approaches to that of the multiuser multi-relay system in the non-cognitive network. Finally, our study is corroborated by representative numerical examples
Numerical simulation of solid tumor blood perfusion and drug delivery during the “vascular normalization window” with antiangiogenic therapy
This Article is provided by the Brunel Open Access Publishing Fund - Copyright @ 2011 Hindawi PublishingTo investigate the influence of vascular normalization on solid tumor blood perfusion and drug delivery, we used the generated blood vessel network for simulations. Considering the hemodynamic parameters changing after antiangiogenic therapies, the results show that the interstitial fluid pressure (IFP) in tumor tissue domain decreases while the pressure gradient increases during the normalization window. The decreased IFP results in more efficient delivery of conventional drugs to the targeted cancer cells. The outcome of therapies will improve if the antiangiogenic therapies and conventional therapies are carefully scheduled
International intermediaries: A systematic literature review and research agenda
Intermediaries such as trading companies, agents and merchants have played a key role in international business for centuries. Despite the growing importance of understanding the phenomenon of intermediaries, there are misperceptions and confusions regarding the concept and value of intermediaries, which result in disconnected and fragmented research findings. This study – based on an analysis of 101 articles published between 1985 and 2021 – aims to synthesise the conceptual developments and provide a more integrated understanding of both sourcing and trading intermediaries whose activities extend across national borders. The findings help to pave the way for further academic research by highlighting what we currently know and do not know about intermediaries, outlining the theoretically grounded research agenda for each of the three identified themes: (1) What are intermediaries? (2) When should intermediaries be used? and (3) How do intermediaries work and develop? The study shows that despite decades of research on this topic, the literature to date has been limited and scattered. Researchers are encouraged to consider the role of intermediaries in a bigger picture where intermediated exchanges exist not only in dyadic relationships, but also in triads or even in broader webs of networks
Adsorption/desorption and electrically controlled flipping of ammonia molecules on graphene
In this paper, we evaluate of the adsorption/ desorption of ammonia molecules
on a graphene surface by studying the Fermi level shift. Based on a physically
plausible model, the adsorption and desorption rates of ammonia molecules on
graphene have been extracted from the measured Fermi level shift as a function
of exposure time. An electric field-induced flipping behavior of ammonia
molecules on graphene is suggested, based on field effect transistor (FET)
measurements
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