In this paper, the delayed state fractional order derivative (DSFOD) is introduced into the existing traditional consensus protocol aiming to improve the robustness of fractional-order multi-agent systems against communication time delay. Both of communication channels with time-delay and without time-delay cases are considered. Based on the frequency-domain analysis and algebraic graph theory, it is shown that properly choosing the intensity of DSFOD can improve the robustness of fractional-order multi-agent systems against communication delay. Finally, a simulated example with simulations is presented to confirm the correctness and effectiveness of the theoretical results.

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Entropy‐forming ability (EFA) is used as a descriptor to identify possible single‐phase high‐entropy nitrides (HENs) from eight cation candidates Al, Si, Ti, V, Cr, Zr, Nb, and Mo. Around 56 five‐cation HEN compositions using density functional theory calculations of 2744 ten‐atom supercells are evaluated. Ten HEN compositions with high EFA values are identified, and among them AlCrNbTiVN5 has the highest EFA value. Cation‐nitrogen bond length statistics shows that HENs with small lattice distortion tend to have large EFA values. The elemental dependence analysis shows that silicon introduces largest lattice distortion and hence small EFA values, which provides useful guidance for element selection of single‐phase HENs.

A low VSWR and high efficiency antenna array operating in the Ku band for satellite communications is presented in this paper. To achieve high radiation efficiency and broad enough bandwidth, all-metal radiation elements and full-corporate waveguide feeding network are employed. As the general milling method is used in the multilayer antenna array fabrication, the E-plane waveguide feeding network is adopted here to suppress the wave leakage caused by the imperfect connectivity between adjacent layers. A 4 × 8 elements array prototype was fabricated and tested for verification. The measured results of proposed antenna array show bandwidth of 6.9% (13.9–14.8 GHz) for VSWR < 1.5. Furthermore, antenna gain and efficiency of higher than 22.2 dBi and 80% are also exhibited, respectively.

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