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This investigation presents an oval slot edge (OSE) antipodal Vivaldi antenna (AVA), hereinafter referred to as Fern AVA (FAVA), with an optimized radiation pattern. The use of OSE provided improvements in the antenna characteristics, especially regarding a lower-frequency limit reduction, an increase of the main lobe (ML) gain, and sidelobe level (SLL) reduction. Those contrasting characteristics are simultaneously obtained through the class of the Palm Tree antennas. The proposed FAVA at 1.5 GHz shows an improved gain of 6.66 dB, -12.9 dB of SLL, and 0 degrees of main lobe squint (MLS), in contrast with 4.41 dB of gain, -4.5 dB of SLL, and 4 degrees of MLS in the conventional AVA. For the FAVA, the notches in an elliptical shape, in addition to mitigating the SLL, direct the E-fields distributions towards the main lobe, which categorizes it into the same class as the Palm Tree Vivaldi Antenna. To study the performance of the proposed antenna for medical applications of near-field microwave imaging, a conceptual proof was performed, thus obtaining the microwave image of a Child Head Phantom, homogeneous and semi-realistic, being possible to detect a brain tumor.

The Paraconsistent Annotated Logic (PAL) is one type of non-classical logics that, differently than classical logic, allows the processing of contradictory signals in its theoretical structure. The Paraconsistent Artificial Neural Cell (PANcell) is the basic block of a set of algorithms that utilizes the interpretation of the lattice of the Paraconsistent Annotated Logic with annotation of two values (PAL2v). The Paraconsistent Artificial Neural Cell of Learning (LPANcell) is a type of PANcell that uses the output as a feedback to the input of the unfavorable degree of evidence in time. The resulting behavior is to learn any real value within a normalized closed range (interval values [0, 1]). This cell can be used in signal analysis, processing, average estimator and as a filter, called PAL2vFilter. The proposed article presents the results of the analysis of a PAL2vFilter, when using the simplified resulting degree of evidence - uE or the resulting degree of real evidence - uRE (when contradiction effects are extracted) as output.