Multi-hop relaying is a fundamental technology that will enable connectivity in large-scale networks such as those encounted in IoT applications. However, the end-to-end transmission rate decreases dramatically as the number of hops increases when half-duplex (HD) relaying is employed. In this paper, we investigate the outage probability and symbol-error rate for both HD and full-duplex (FD) transmission schemes in multi-hop networks subject to interference from randomly distributed thirdparty devices. We model the locations of the interfering devices as a Poisson point process. We derive a closed-form expression for the outage probability and approximations for the symbol-error rate for HD and FD transmissions employing BPSK and QPSK. The symbol-error rate results are obtained by using a Markov chain model for the multi-hop decode-and-forward links. This model accurately accounts for the nonlinear dynamical nature of the network, whereby erroneous symbol decoding can be "corrected" by a second erroneous decoding operation later in the network. We verify the analytical results through simulations and show the HD and FD schemes can be utilized to reduce the error-rate and outage probability of the system according to different residual self-interference levels and interferer densities. The results provide clear guidelines for implementing HD and FD in multi-hop networks.

The exchange bias effect is observed in a diluted magnetic system synthesized with 5% volume fraction of Co3O4 anchored on reduced graphene oxide (rGO) sheet below the antiferromagnetic transition temperature of Co3O4. The glassy magnetic phase below 5 K has been established by relaxation memory studies performed in ZFC protocol.

γ-TiAl has been a hot topic of research for more than a few decades now, since it is a potential candidate for high temperature structural applications. In this paper, dispersion strengthening of γ based TiAl alloy, produced by means of centrifugal casting, has been performed to increase its mechanical properties beyond those of standard TiAl alloys. After a careful selection of the alloy composition based on the desired properties, several samples were produced by means of investment casting. This work focused on the effect of Al2O3 nano- and micro-dispersoids on the mechanical properties of the considered TiAl alloy. Microstructural investigations were carried out to study both the alloy microstructure and the Al2O3 dispersion homogeneity. Samples of the produced alloy were subjected to four-point bending tests at different temperatures for evaluating the effect of dispersed particles on mechanical properties. The results of this study were promising and showed that Al2O3 dispersion determined an increase of the mechanical properties at high temperatures. The Young’s modulus was 30% higher than that of the reference alloy in the lower temperature range. Over the temperature range 800–950 °C the dispersion strengthening affected the yield stress by increasing its value of about 20% even at 800 °C. A detailed evaluation of fracture surfaces was carried out to investigate fracture mechanisms.

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