We have performed a first-principles study on structural, electronic, elastic, mechanical, thermodynamic, and thermoelectric (TE) properties of RbSnX 3 (X = F, Cl, and Br) perovskites. The study is performed using the full potential linearized augmented plane wave method via Wien2k code under different exchange-correlation potentials. The considered materials exhibit structural stability in the cubic phase (Pm-3m symmetry) with semiconducting nature in all exchange potentials. Further, analysis of elastic constants in this cubic phase reveals mechanical stability. RbSnF 3 is found to be stiffer than the other considered perovskites. In their thermodynamic picture, perovskites display sound thermodynamic nature for heat capacity, Debye temperature, Grüneisen constant, entropy, and thermal expansion coefficient under the temperature of 0 to 1200 K and pressure of 0 to 50 GPa. Furthermore, TE performance has been analyzed by estimating the thermopower and figure of merit (temperature range 50-1200 K). The predicted values of the figure of merit for RbSnCl 3 and RbSnBr 3 are 0.62 and 0.60 at 1200 K, respectively, suggesting materials' application in TE and mechanical devices.

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Summary In Fifth Generation (5G) Heterogeneous Mobile Networks (HetNets), deploying dense small cell networks makes user association more challenging. The process of collecting cell load information from the User Equipments (UEs) and broadcasting the feedback message involves significant overhead and time complexity. Moreover, the UEs may not know the optimum cell to reselect, satisfying its data rate requirements. In order to overcome these drawbacks, in this paper, we propose to design an Hierarchical and Hybrid Cell Load Balancing (HHCLB) technique using Selective Handoff. In this technique, the UEs of each cell are grouped into clusters depending on their proximity distance. Each cluster contains a cluster controller (CC) which is in charge of determining the intra‐cell load and redirecting the cell‐reselection request of a UE. If the data rate of any UE in a cluster becomes less than its required rate, then the cell reselection process is performed. By simulation results, it is shown that load balancing can be done proactively (implicitly) by the CCs when the load is unbalanced or can be done on demand (explicitly) when a UE send a request for cell reselection. In the case of Macro cells, HHCLB attains 71% higher throughput for low load scenario and 59% higher throughput for high load scenario. Similarly, in the case of Femto cells, HHCLB attains 19% higher throughput for low load scenario and 27% higher throughput for high load scenario.

An ever-increasing demand for energy due to increasing usage is driving the scientists to find out materials for their technological applications. In this regard, thermoelectric materials are considered to be excellent candidates as energy sources. Further, for the suitability of materials in device fabrication, the study of various thermophysical parameters is always required. We have therefore tried to explore various performances of SrCeO 3 perovskite, systematically using density functional theory with different potentials. The electronic band structure profile of SrCeO 3 shows semiconducting behaviour in the ground state. Thermoelectric performance indicators like Seebeck coefficient, thermal conductivity, electrical conductivity, and power factor have been estimated within temperature 0 to 700 K. Interestingly, SrCeO 3 displays a figure of merit value 0.27 at 700 K.

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