36,095 research outputs found
Levantamento de reconhecimento de solos e avaliação do potencial de terras para irrigação do município de Simão Dias, Sergipe.
bitstream/CNPS-2010/14930/1/comtec39-2006-simao-dias.pd
Performance Analysis of Network-Assisted Two-Hop D2D Communications
Network-assisted single-hop device-to-device (D2D) communication can increase
the spectral and energy efficiency of cellular networks by taking advantage of
the proximity, reuse, and hop gains when radio resources are properly managed
between the cellular and D2D layers. In this paper we argue that D2D technology
can be used to further increase the spectral and energy efficiency if the key
D2D radio resource management algorithms are suitably extended to support
network assisted multi-hop D2D communications. Specifically, we propose a
novel, distributed utility maximizing D2D power control (PC) scheme that is
able to balance spectral and energy efficiency while taking into account mode
selection and resource allocation constraints that are important in the
integrated cellular-D2D environment. Our analysis and numerical results
indicate that multi-hop D2D communications combined with the proposed PC scheme
can be useful not only for harvesting the potential gains previously identified
in the literature, but also for extending the coverage of cellular networks.Comment: 6 pages and 7 figure
Solution for a local straight cosmic string in the braneworld gravity
In this work we deal with the spacetime shaped by a straight cosmic string,
emerging from local gauge theories, in the braneworld gravity context. We
search for physical consequences of string features due to the modified
gravitational scenario encoded in the projected gravitational equations. It is
shown that cosmic strings in braneworld gravity may present significant
differences when compared to the general relativity predictions since its
linear density is modified and the deficit angle produced by the cosmic string
is attenuated. Furthermore, the existence of cosmic strings in that scenario
requires a strong restriction to the braneworld tension: , in Planck units.Comment: 7 pages, 3 figure
Detecção das fontes de sedimentos no Rio São Francisco: uma abordagem utilizando técnicas de sensoriamento remoto - Instituto de Milênio Semi-Árido.
Até pouco tem po se acreditava que o problema dos sedimentos se reduzia ao simples fato do mau aspecto visual das águas de um determinado rio, lago ou represa. A medida que as investigações foram se aprofundando, se demonstrou que as águas carregadas de sedimentos transportavam fertilizantes e inseticidas (contaminação química), argilas e partículas de matéria orgânica, cuja elevada capacidade de absorção lhe permite reter bactérias de qualquer tipo, nocivas a saúde. Por outro lado, os sedimentos, fisicamente, produzem o assoreamento de obras de infra-estruturas, provocam inundações na parte alta e desestabilizam os curso d'águ
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