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Automated building extraction is imperative for several geospatial applications such as monitoring disaster-affected buildings and urban planning. Existing deep learning (DL)-based building extraction methods fail to capture high-level semantic features due to the complex nature and diverse appearance of visually similar structures. To address this issue, in this letter, we propose an enhanced multi-scale attentive feature fusion network (EMAFF-Net) for building extraction from remote sensing (RS) images. EMAFF-Net is an end-to-end DL architecture based on U-Net that includes: i) an encoder; ii) an enhanced multi-scale feature fusion (EMFF) module; iii) a refined multi-scale convolutional block attention (RM-CBAM) module and iv) a decoder with refinement layers. To extract multi-scale contextual information, we incorporate an RM-CBAM module into the lateral connections of encoder-decoder layers of EMAFF-Net. Further, a novel EMFF module is integrated to obtain fine-grained features from the lowest encoder layer with minimal trainable parameters required. We evaluate the performance of the proposed network on two benchmark datasets: Massachusetts (MAS) and WHU building datasets. The experimental results show that the proposed approach outperforms the existing reference methods showcasing its potential in practical applications. [ABSTRACT FROM AUTHOR]

Li3Fe2(PO4)3 is interesting because of its technological application and environmentally benign nature. Nanocrystalline Li3Fe2(PO4)3 is synthesized by a solution combustion technique. The role of fuels/complexing agents in deciding the structural parameters and ac electrical behavior is investigated in this study. Antiferromagnetic nature and direct bandgap energy of 3.09 eV are recognized in the material. Enhanced conduction is established through mobility of Li+ ion in four co-ordination in the modified monoclinic symmetry and high temperature stability through orthorhombic symmetry. Quality of electrical data is confirmed through a Kramers-Kronig test and electrical relaxation parameters are obtained from modulus analysis. Scaling analysis of modulus data confirmed the time-temperature superposition principle. [ABSTRACT FROM AUTHOR]

Highlights: [•] Solution combustion technique and preparation of nanocrystalline olivine materials. [•] Olivine type LiNiPO4 based nanocrystalline materials and characterization. [•] AC electrical studies on olivine type LiNi1−x M x PO4(M=Cu2+/Mg2+)based materials. [•] Enhancement of ionic conductivity in the nanocrystalline phase of LiNiPO4 material. [Copyright &y& Elsevier]

Abstract: Thermally stable Na3Cr2(PO4)3 nano-crystallites are synthesized through novel solution combustion technique using glycine fuel in three molar ratios. Effects of fuel molar ratio on structural and electrical properties are investigated. Reaction parameters like fuel molar ratio, flame temperature and number of moles of gases evolved, play a major role in deciding physical and electrical properties. Out of the synthesized samples, one which contains fuel in 1:1 molar ratio shows highest grain conductivity of 2.35×10−6 Scm−1. Improved conductivity is elucidated by least size and highest density of the crystallites, which in turn is decided by the flame temperature. Ac electrical properties are investigated using complex impedance spectroscopy. Activation energies for dc conduction and relaxation are determined and the results are reported. [Copyright &y& Elsevier]

Abstract: Nano-crystallites of Li1.3Ti1.7Al0.3(PO4)2.9(VO4)0.1 NASICON type material are prepared by means of solid-state reaction of a stoichiometric mixture after milling it for 22 and 55h. The milling reduces the average crystallite size of the ceramic to 80 and 60nm, respectively. Mechanical milling changes structural parameters and the strain induced at the grain-boundaries plays a major role in improving electrical conductivity. An order of magnitude increase in electrical conductivity is observed in the material milled for 55h compared to the unmilled material, which is also reflected in permittivity loss. Modulus and permittivity representations substantiate the constriction effect of grain-boundaries observed in the complex impedance representation. [Copyright &y& Elsevier]

Abstract: Nanocrystalline Li2Ni1−x Mg x TiO4 powders were synthesized using a sol–gel technique. They were crystallized in cubic rock salt phase with space group Fm-3m. The synthesis was carried out in nitrogen atmosphere using citric acid as fuel. AC electrical properties of the nanocrystalline Li2Ni1−x Mg x TiO4 were investigated by complex conductivity and impedance. The scaling behavior in the electrical conductivity and impedance confirmed the time temperature superposition principle of relaxation mechanism. [Copyright &y& Elsevier]