We report the magnetic stability, antiferromagnetic ordering, electronic, magnetic, and thermoelectric properties of BaMn2As2 employing the full-potential augmented-plane wave method under the framework of density functional theory. The exchange-correlation energy was treated using the Perdew-Burke-Ernzerhof generalized gradient approximation (PBE-GGA) and GGA plus Hubbard U parameter method. From structural relaxation, we reveal that antiferromagnetic (A-AFM) state is more appropriate for BaMn2As2 than other known configurations. Under electronic properties, BaMn2As2 shows metallic nature in paramagnetic (PM) and antiferromagnetic phase (AFM). Further, the decrease in electrical conductivity over the entire temperature range characterize the metallic nature of BaMn2As2. The electronic band structure calculation demonstrates that Mn-3d and As-4p orbital hybridization are essential for the band gap formation, suggesting BaMn2As2, a hybridization-gap semiconductor. The total magnetic moment of BaMn2As2 in ferromagnetic phase is ~9.54 μB, with a major contribution from Mn atom. In thermoelectric, we obtain a negative Seebeck coefficient (S), n-type electrical conductivity, and a maximum ZT value of 0.40. Our study suggests BaMn2As2 as a novel candidate for spintronics and waste heat management.

In this era of communication, exponentially growing networks bring a lot of challenges to address for smoother network functionalities. Among them is efficiency in handling packet traffic to avoid and control congestion. A particular case is applicable to Vehicular Ad-hoc Networks, which are known with unbalanced resource utilisation, communication overheads, high transmission delay and least transmission capacity. This paper aims to minimise the delay and jitter for enhancing the Quality of Service (QoS) in Vehicular Adhoc Networks (VANET) using tabu search algorithm with multi-channel allocation capability. We proposed a scheme that prioritises each message considering the basis of message type or its substances, such as crisis, reference point, and administration oriented etc., and uses tabu search for scheduling the transmission of queued messages in order to enhance the efficiency, security, and durability of VANET. A comprehensive simulation is conducted to validate the proposed scheme and to evaluate the performances in comparison with other state-of-the-art approaches.

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Our study used the full-potential linearized augmented plane waves (FP-LAPW) method to conduct a first-principles evaluation of the structural, electronic, and magnetic properties of ThMn2X2 (X = Si and Ge) compounds. To establish theoretical dependability with the currently available experimental results, computations for the structural findings of ternary intermetallic thorium (Th)-based compounds were achieved using the generalized gradient approximation in the scheme of Perdew–Burke–Ernzerhof (PBE–GGA) potential, while the generalized gradient approximation plus the Hubbard U (GGA + U) approach was employed to improve the electrical and magnetic properties. In contrast with both the paramagnetic (PM) and antiferromagnetic (AFM) phases, the ThMn2X2 compounds were optimized in a stable ferromagnetic (FM) phase, which was more suited for studying and analyzing magnetic properties. The electronic band structures (BS) and the density of state (DOS) were computed using the two PBE–GGA and GGA + U approximations. The thorium (Th)-based ThMn2X2 compound has full metallic character, due to the crossing and overlapping of bands across the Fermi level of energy, as well as the absence of a gap through both spin (up and down) channels. There was a significant hybridization between (Mn-d and (X = Si and Ge)-p states of conduction band with Th-f states in the valence band. The total magnetic moment of ThMn2Si2 in the ferromagnetic phase was 7.94534 μB, while for ThMn2Ge2 it was 8.73824 μB with a major contribution from the Mn atom. In addition, the ThMn2Ge2 compound’s total magnetic moment confirmed that it exhibits higher ferromagnetism than does the ThMn2Si2 compound.

This chapter briefly introduces the data center network and reviews the challenges for future intra-data-center networks in terms of scalability, cost effectiveness, power efficiency, upgrade cost, and bandwidth utilization. Current data center network architecture is discussed in detail and the drawbacks are pointed out in terms of the above-mentioned parameters. A detailed background is provided that how the technology moved from opaque to transparent optical networks. Additionally, it includes different data center network architectures proposed so far by different researchers/team/companies in order to address the current problems and meet the demands of future intra-data-center networks.