Unified radio and network control across heterogeneous hardware platforms

Experimentation is an important step in the investigation of techniques for handling spectrum scarcity or the development of new waveforms in future wireless networks. However, it is impractical and not cost effective to construct custom platforms for each future network scenario to be investigated. This problem is addressed by defining Unified Programming Interfaces that allow common access to several platforms for experimentation-based prototyping, research, and development purposes. The design of these interfaces is driven by a diverse set of scenarios that capture the functionality relevant to future network implementations while trying to keep them as generic as possible. Herein, the definition of this set of scenarios is presented as well as the architecture for supporting experimentation-based wireless research over multiple hardware platforms. The proposed architecture for experimentation incorporates both local and global unified interfaces to control any aspect of a wireless system while being completely agnostic to the actual technology incorporated. Control is feasible from the low-level features of individual radios to the entire network stack, including hierarchical control combinations. A testbed to enable the use of the above architecture is utilized that uses a backbone network in order to be able to extract measurements and observe the overall behaviour of the system under test without imposing further communication overhead to the actual experiment. Based on the aforementioned architecture, a system is proposed that is able to support the advancement of intelligent techniques for future networks through experimentation while decoupling promising algorithms and techniques from the capabilities of a specific hardware platform

Dirac-Surface-State-Dominated Spin to Charge Current Conversion in the Topological Insulator (Bi0.22Sb0.78)2Te3(Bi_{0.22}Sb_{0.78})_2Te_3 Films at Room Temperature

We report the spin to charge current conversation in an intrinsic topological insulator (TI) $(Bi_{0.22}Sb_{0.78})_2Te_3$ film at room temperature. The spin currents are generated in a thin layer of permalloy (Py) by two different processes, spin pumping (SPE) and spin Seebeck effects (SSE). In the first we use microwave-driven ferromagnetic resonance of the Py film to generate a SPE spin current that is injected into the TI $(Bi_{0.22}Sb_{0.78})_2Te_3$ layer in direct contact with Py. In the second we use the SSE in the longitudinal configuration in Py without contamination by the Nernst effect made possible with a thin NiO layer between the Py and $(Bi_{0.22}Sb_{0.78})_2Te_3$ layers. The spin-to-charge current conversion is attributed to the inverse Edelstein effect (IEE) made possible by the spin-momentum locking in the electron Fermi contours due to the Rashba field. The measurements by the two techniques yield very similar values for the IEE parameter, which are larger than the reported values in the previous studies on topological insulators.Comment: 18 pages and 7 figure

Main competencies to manage complex defence projects

This research adds a comprehensive way of assessing competencies, contrasting with the usual reductionist approach that uses off-the-shelf instruments. The study reveals 27 competencies to manage complex projects based upon a comprehensive analysis of 22 interviews with senior practitioners associated with the most strategic projects from the Brazilian Army. These competencies were divided into 10 groups, namely influencing, communication, team working, cognitive, management, contextual skills, professionalism, project management knowledge, and personal skills and attributes. Surprisingly, both emotional skills and social competencies were not prominent. The results contribute to advance our knowledge by revealing that practitioners involved in complex defence projects value more technical and individual competencies. This study analyses competencies across several complex projects in the defence sector, providing insights to practitioners and expanding the academic debate focused on other industries and single cases. Organisations might use the competencies to recruit, select, and develop human resources involved in complex defence initiatives

Impact of nitrite on the microbiological quality of a Portuguese Salpicão

info:eu-repo/semantics/publishedVersio

Ocorrência de Borrelia spp. em cultura de células embrionárias do carrapato Boophilus microplus (Acari: Ixodidae) no Estado do Mato Grosso do Sul, Brasil.

O presente trabalho teve como objetivo reportar a ocorrência de Borrelia spp. em culturas de células embrionárias de Boophilus microplus infectados naturalmente. Sete dias após o início de uma nova cultura primária de células embrionárias do carrapato B. microplus, incubadas a 31°C, notou-se que as células começaram a degenerar. Ao exame em microscópio de contraste de fase detectou-se a presença de microrganismos alongado e com grande mobilidade. Lâminas de microscópio confeccionadas com amostras do sobrenadante da cultura, hemolinfa e massa de ovos, coradas pelo May Grünwald- Giemsa, permitiram a visualização de espiroquetas. O exame morfológico do microrganismo e sua visualização em B. microplus sugere ser Borrelia spp