Spectrum sensing is needed in frequency agile cognitive radio systems, cognitive radar systems as well as in (cognitive) electronic warfare systems. This paper studies window based detectors where window shapes can be matched for the expected spectrum. The provided analytical results for the probabilities of false alarm and detection are valid for arbitrary windows.
View Article and Find Full Text PDFReconfigurations of synchronized large-scale networks are thought to be central neural mechanisms that support cognition and behavior in the human brain. Magnetoencephalography (MEG) recordings together with recent advances in network analysis now allow for sub-second snapshots of such networks. In the present study, we compared frequency-resolved functional connectivity patterns underlying reading of single words and visual recognition of symbol strings.
View Article and Find Full Text PDFPhilos Trans A Math Phys Eng Sci
February 2018
In this paper, we have optimized a low-temperature atomic layer deposition (ALD) of SiO using AP-LTO® 330 and ozone (O) as precursors, and demonstrated its suitability to surface-modify temperature-sensitive bio-based films of cellulose nanofibrils (CNFs). The lowest temperature for the thermal ALD process was 80°C when the silicon precursor residence time was increased by the stop-flow mode. The SiO film deposition rate was dependent on the temperature varying within 1.
View Article and Find Full Text PDFA concept for direct surface modification on self-standing films of cellulose nanofibrils (CNF) is demonstrated using an aminosilane group in cellulose compatible solvent (dimethyl acetamide, DMA). The chemically modified structure efficiently prevents the oxygen molecules from interacting with the nanocellulose film in the presence of water molecules. Oxygen permeability values lower than 1mLmmmdayatm were achieved at extremely high levels of relative humidity (RH95%).
View Article and Find Full Text PDFHerein we present a simple method to render cellulosic materials highly hydrophobic while retaining their breathability and moisture buffering properties, thus allowing for their use as functional textiles. The surfaces are coated via layer-by-layer deposition of two natural components, cationic poly-l-lysine and anionic carnauba wax particles. The combination of multiscale roughness, open film structure, and low surface energy of wax colloids, resulted in long-lasting superhydrophobicity on cotton surface already after two bilayers.
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