CoNAN: Conditional Neural Aggregation Network For Unconstrained Face Feature Fusion

Face recognition from image sets acquired under unregulated and uncontrolled settings, such as at large distances, low resolutions, varying viewpoints, illumination, pose, and atmospheric conditions, is challenging. Face feature aggregation, which involves aggregating a set of N feature representations present in a template into a single global representation, plays a pivotal role in such recognition systems. Existing works in traditional face feature aggregation either utilize metadata or high-dimensional intermediate feature representations to estimate feature quality for aggregation. However, generating high-quality metadata or style information is not feasible for extremely low-resolution faces captured in long-range and high altitude settings. To overcome these limitations, we propose a feature distribution conditioning approach called CoNAN for template aggregation. Specifically, our method aims to learn a context vector conditioned over the distribution information of the incoming feature set, which is utilized to weigh the features based on their estimated informativeness. The proposed method produces state-of-the-art results on long-range unconstrained face recognition datasets such as BTS, and DroneSURF, validating the advantages of such an aggregation strategy.Comment: Paper accepted at IJCB 202

Synthesis and Antimicrobial Activity of Novel 3-[1-(3-nitrophenyl)-ethyl]-1-(indole-1-yl) Substituted Aryl/alkyl-phosphinoyl/thiophosphinoyl/ selenophosphinoyl-1H-indole Derivatives

Syntheses of novel 3-[1-(3-nitrophenyl)-ethyl]-1-(indole-1-yl) substituted aryl/alkyl phosphinoyl/thiophosphinoyl/selenophosphinoyl-1H-indole derivatives were accomplished in two steps. The synthetic route involves the cyclisation of equimolar quantities of 3-[1H-3-indolyl(3-nitrophenyl)methyl]-1H-indole with dichlorophenyl phosphine/ethyldichlorophosphite in the presence of triethylamine in dry acetonitrile at room temperature. These compounds were further converted to the corresponding oxides, sulphides and selenides by reacting them with hydrogen peroxide, sulphur and selenium, respectively. The structures of the novel products were established by elemental analyses, IR, 1H, 13C and 31P NMR and mass spectroscopy. They were screened for antibacterial and antifungal activity against Staphylococcus aureus/Klebsiella pneumoniae and Pellicularia solmanicolor/Macrophomina phaseolina, respectively.Keywords: Bisindolylalkanes, alkyl/aryl phosphorodichloridates, antimicrobial activit

Facile and scalable preparation of bovine serum albumin stabilized cobalt sulfide nanostructures with various morphologies

We present a protein-assisted method for the facile and scalable synthesis of Cobalt sulfide (CoS) nanostructures with various morphologies using bovine serum albumin (BSA) as a stabilizing agent. The CoS samples prepared from 10:1 volume ratio of Cobalt (Co):Sulfur (S) and 1:10 volume ratio of Co:S at 0.01% w/v amount of BSA shows 3D flowers with an average diameter of 510 nm and hollow spheres about 900 nm in average diameter, respectively. The CoS samples prepared from 0.01, 0.1 and 0.5% w/v amounts of BSA at 1:1 volume ratio of Co:S shows nanosheet based porous clusters, nanosheet based partially porous clusters and aggregated spheres, respectively. Fourier transform infrared spectroscopy study confirms that the obtained BSA stabilized CoS nanostructures are stabilized by hydroxyl and amine groups present in the BSA molecules. © 2021 Elsevier B.V.1

On the Purity of Atmospheric Glow-Discharge Plasma

Purity of the glow-discharge plasma at atmospheric pressure for surface modification applications is always debatable, since it works at ambient atmosphere. We have demonstrated on the use of optical emission spectroscopy to test the purity of this kind of plasma. The effect of gas flow pattern, nature of gas, and its flow rate on the plasma chemistry was studied. The importance of proper system design in maintaining a uniform flow of heavy and inert gases as carrier gas in atmospheric glow-discharge plasma was confirmed. The surface of a plasma-treated PET sample was analyzed using X-ray photoelectron spectroscopy to verify the studies on plasma purity done using emission spectrum

On the quality of hydrogenated amorphous silicon deposited by sputtering

Amorphous hydrogenated silicon (a-Si:H) is well-known material in the global semiconductor industry. The quality of the a-Si:H films is generally decided by silicon and hydrogen bonding configuration (Si-H-x, x=1,2) and hydrogen concentration (C-H). These quality aspects are correlated with the plasma parameters like ion density (N-i) and electron temperature (T-e) of DC, Pulsed DC (PDC) and RF plasmas during the sputter-deposition of a-Si:H thin films. It was found that the N-i and T-e play a major role in deciding Si-H-x bonding configuration and the C-H value in a-Si:H films. We observed a trend in the variation of Si-H and Si-H-2 bonding configurations, and C-H in the films deposited by DC, Pulsed DC and RF reactive sputtering techniques. Ion density and electron energy are higher in RF plasma followed by PDC and DC plasma. Electrons with two different energies were observed in all the plasmas. At a particular hydrogen partial pressure, RF deposited films have higher C-H followed by PDC and then DC deposited films. The maximum energy that can be acquired by the ions was found to be higher in RF plasma. Floating potential (V-f) is more negative in DC plasma, whereas, plasma potential (V-p) is found to be more positive in RF plasma. (C) 2014 Elsevier Ltd. All rights reserved

Effect of iodine concentration on the photovoltaic properties of dye sensitized solar cells for various I-2/LiI ratios

In the present study, the effect of iodine concentration on the photovoltaic properties of dye sensitized solar cells (DSSC) based on TiO2 nanoparticles for three different ratios of lithium iodide (LiI) and iodine (I-2) has been investigated. The electron transport properties and interfacial recombination kinetics have been evaluated by electrochemical impedance spectroscopy (EIS). It is found that increasing the concentration of lithium iodide for all ratios of iodine and lithium iodide decreases the open-circuit voltage (V-oc) whereas short circuit current density (J(sc)) and fill factor (FF) shows improvement. The reduction in V-oc and increment in J(sc) is ascribed to the higher concentration of absorptive Li+ cations which shifts the conduction band edge of TiO2 positively. The increase in FF is due to the reduction in electron transport resistance (R-omega) of the cell. In addition for all the ratios of LiI/I-2 increasing the concentration of I-2 decreases the V-oc which is attributed to the increased recombination with tri-iodide ions (I-3(-)) as verified from the low recombination resistance (R-k) and electron lifetime (tau) values obtained by EIS analysis. (C) 2012 Elsevier Ltd. All rights reserved

Estimating the number density and energy distribution of electrons in a cold atmospheric plasma using optical emission spectroscopy

Cold atmospheric plasmas are generous sources of chemically active species, the reaction rates which can be predicted only if the electron number density and the electron energy distribution function are known. Here, the authors present a procedure for estimating both these parameters from the optical emission spectrum of an argon plasma. The peaks in the spectrum were curve fitted with Voigt profiles, and their widths and areas were mapped to the number density and energy distribution of electrons in the plasma, using the mathematical models for Stark broadening and Corona population, respectively. These plasma parameters were optimized to establish a good match between the simulated and the experimental peak attributes. This analysis estimated the value of the electron number density to be approximately 1.5 x 10(15) cm(-3) and the mean electron temperature to be approximately 0.37 eV in their plasma. It also predicted that the energy distribution of electrons can be closely approximated using a Maxwellian distribution. Published by the AVS

Size-Dependent Tuning of Mn2+ d Emission in Mn2+-Doped CdS Nanocrystals: Bulk vs Surface

We show that the characteristic Mn2+ d emission color from Mn2+-doped CdS nanocrystals can be tuned over as much as 40 nm, in contrast to what should be expected from such a nearly localized d-d transition. This is achieved surprisingly by a fine-tuning of the host particle diameter from 1.9 to 2.6 nm, thereby changing the overall emission color from red to yellow. Systematic experiments in conjunction with state-of-the-art ab initio calculations with full geometry optimization establish that Mn2+ ions residing at surface/subsurface regions have a distorted tetrahedral coordination resulting in a larger ligand field splitting. Consequently, these near-surface Mn2+ species exhibit a lower Mn2+ d emission energy, compared to those residing at the core of the nanocrystal with an undisturbed tetrahedral coordination. The origin of the tunability of the observed Mn2+ emission is the variation of emission contributions arising from Mn2+ doped at the core, subsurface, and surface of the host. Our findings provide a unique and easy method to identify the location of an emitting Mn2+ ion in the nanocrystal, which would be otherwise very difficult to decipher