-In this work we utilize the model for calculation of the interference power by partially overlapping channels introduced in [1] and combine it with the Signal to Interference plus Noise (SINR) criterion for signal capture to quantify the effect of adjacent channel interference (ACI) in 802.11a. We validate the results from our theoretical model by applying it on an in-lab testbed, in which we use signal splitters/combiners and fixed attenuators to emulate the wireless channel. Our experiments show that the neighboring channel interference affects the 802.11a with two mechanisms: the packet capture at the receiver and the Clear Channel Assessment (CCA) mechanism. We quantify the effect of ACI in these mechanisms in terms of throughput. Our results indicate that equipping a single node with multiple interfaces requires careful channel allocation and physical antenna separation, since throughput can be severely degraded. Our future work focuses on field experimenting with 802.11a multi-radio mesh nodes in order to introduce the antenna characteristics in our model.

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We present an experimental apparatus that allows microsecond-resolved ellipsometric and absorption measurements. The apparatus is based on an optical cavity containing a Dove prism, in which light undergoes total internal reflection (TIR), while the data acquisition is based on software defined radio technology and custom-built drivers. We demonstrate the ability to sense rapid variations in the refractive index above the TIR interface for arbitrarily long times with a temporal resolution of at least 2 μs.

In this study, Cuprous Oxide (Cu2O), known for its mechanism against bacteria, was used as filler to induce biocidal properties on a common commercial resin stereolithography (SLA) 3D printing resin. The aim was to develop nanocomposites suitable for the SLA process with a low-cost process that mimic host defense peptides (HDPs). Such materials have a huge economic and societal influence on the global technological war on illness and exploiting 3D printing characteristics is an additional asset for these materials. Their mechanical performance was also investigated with tensile, flexural, Charpy’s impact, and Vickers microhardness tests. Morphological analysis was performed through scanning electron microscopy (SEM), atomic force microscopy (AFM), and energy-dispersive X-ray spectroscopy (EDS) analysis, while the thermal behavior was studied through Thermogravimetric Analysis (TGA). The antibacterial activity of the fabricated nanocomposites was investigated using a screening agar well diffusion method, for a gram-negative and a gram-positive bacterium. Three-dimensional printed nanocomposites exhibited antibacterial performance in all loadings studied, while their mechanical enhancement was approximately 20% even at low filler loadings, revealing a multi-functional performance and a potential of Cuprous Oxide implementation in SLA resin matrices for engineering and medical applications.

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