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Solid-state synthesis process with a higher thermal treatment of optimized sintering temperature of 1000 °C was utilized to develop the MgBiFeTiO6 (MBFTO) orthorhombic (A21am) single-phase polycrystalline ceramic oxide. The initial investigation by the XRD method suggests an Aurivillius-type compound like Am-1BmO3m, m = 5, while Rietveld analysis and tolerance factor (τ ~ 0.8) were also involved as an additional approximation tools to verify the structural formation. The SEM image confirmed a single-phase polycrystalline compound formation with av. grain size (~ 0.614 μm) is greater as compared to mean crystallites (~ 11 nm). The EDS spectra and elemental color mapping suggest the purity and uniform distribution of essential element over the surface of the sample. The ultraviolet–visible (UV–vis) absorbance spectra have a higher threshold wavelength (~ 630 nm) with a direct bandgap of ~ 2.36 eV suggesting better absorbance features in IR and visible radiation range, thus it can be utilized as a source material in photovoltaic and photocatalytic applications. The electrical and transport property was examined over 25–500 °C with a frequency sweeping 100–5 M Hz. The compound possesses an average ambient dielectric (~ 433) and low loss (~ 0.071) value at 1 kHz. The contribution of grains and grain barriers effect in semiconductance essence while an out of Debye-based relaxation mechanism that relies on the heat-dependent carrier mobility were verified as well. The material exhibited weak ferromagnetic behaviour and non-zero electric polarisation, with antiferromagnetic behaviour predominating. The outcomes of the examination suggest the present sample can be used in photocatalytic and dielectric material in suitable electronic equipments. [ABSTRACT FROM AUTHOR]

In this report, a solid-state approach was followed to synthesize a new double perovskite MgBi1.2Fe0.8TiO6. The initial inspection of the material was carried out through XRD analysis and found Arruvillias-type compounds Am−1BmO3m+1, m = 5. The tolerance factor (τ ~ 0.8) was calculated by approximation tools and reveals the presence of structural distortion. The SEM image suggests the development of polycrystalline behavior and shows av. grain size ~ 1.3 μm as compared to (~ 14 nm) av. crystallites. The UV–visible absorbance nature shows a higher threshold wavelength of about 657 nm and a direct bandgap of ~ 2.10 eV suggesting that the material has good absorbance features over IR and visible emission. The compound exhibits av. the dielectric constant, ~ 747, and low loss ~ 0.360 in ambient conditions, while the transition temperature appears above ~ 234 °C at 100 Hz applied field. Heat-dependent carrier mobility indicates bulk-grain and their boundary effect's contribution to semiconductor behavior and non-Debye relaxation mechanism. The non-zero electric polarization and ferromagnetism are also observed in the substance. The synthesized sample can be a promising material in energy and data-storing electronic equipment. [ABSTRACT FROM AUTHOR]

A polycrystalline ceramic oxide, BaFe2MnO6 was produced through a regular solid-state route. The phase creation in the synthesized substance was investigated through X-ray diffraction (XRD) technique. The present material has found with made up of a single phase orthorhombic structure. The electrical properties of the compound were recorded through an LCR meter for a broader range of frequencies and temperatures. This perovskite oxide material possesses a large relative permittivity (ɛr = 1139) and low dielectric loss (tanδ = 0.421) at the ambient atmospheric condition, while the curie temperature arise beyond 450 °C. The resultant dielectric properties of this material assure its promising candidature for feasible applications in smart electronic devices such as dielectric material in ceramic capacitors. [ABSTRACT FROM AUTHOR]

The present study aims to establish a Genetic Algorithm (GA) methodology to optimise the missile gliding trajectory. The trajectory optimisation was carried out by discretising the angle of attack (AOA), subsequent transformation of the optimal control problem to a nonlinear programming problem (NLP), and resolving the optimal control problem to attain a maximised gliding range. GA is employed for resolving optimal control problem. Taguchi design of experiments was proposed contrary to the full factorial method to ascertain the GA parameters. The experiments were designed as per Taguchi's L27 orthogonal array. The systematic reasoning ability of the Taguchi method is exploited to obtain better selection, crossover, and mutation operations, and consequently, enhance GA performance. An analysis of variance (ANOVA) is performed to evaluate the influencing factors in the results. Crossover function and population size are observed as impacting parameters in trajectory optimisation, accompanied by selection, crossover fraction, mutation rate, and number of generations. An Artificial Neural Network (ANN) approach was enforced to anticipate the significance of GA parameters. Based on Taguchi design of experiments, analysis of variance, and artificial neural network methods the optimal parameters of GA were selected. It is observed that the maximum gliding distance is achieved after GA parameter tuning. It is noticed from the simulation results that the missile gliding range is enhanced in comparison to earlier ones. The simulation results also show the efficiency of the proposed procedure through different test cases. [ABSTRACT FROM AUTHOR]

The proposed research deals with selection of particle swarm optimization (PSO) algorithm parameters for missile gliding trajectory optimization relying on Taguchi design of experiments, analysis of variance (ANOVA) and artificial neural networks (ANN). Population size, inertial weight and acceleration coefficients of PSO were chosen for the present study. The experiments have been designed as per Taguchi's design of experiments using L25 orthogonal array for selection of better PSO parameters. Missile gliding trajectory is optimized by discretizing angle of attack as control parameter, consequent conversion of optimal control problem to nonlinear programming problem (NLP) and finally solving the problem using PSO with optimized parameters to obtain optimum angle of attack and realization of maximum gliding range. Simulation results portrayed that the gliding range is maximized and missile glide distance is enhanced compared to earlier experiments. The efficiency of proposed approach was verified via different test scenarios. [ABSTRACT FROM AUTHOR]