3D computer vision based on machine learning with deep neural networks: A review

Recent advances in the field of computer vision can be attributed to the emergence of deep learning techniques, in particular convolutional neural networks. Neural networks, partially inspired by the brain's visual cortex, enable a computer to “learn” the most important features of the images it is shown in relation to a specific, specified task. Given sufficient data and time, (deep) convolutional neural networks offer more easily designed, more generalizable, and significantly more accurate end‐to‐end systems than is possible with previously employed computer vision techniques. This review paper seeks to provide an overview of deep learning in the field of computer vision with an emphasis on recent progress in tasks involving 3D visual data. Through a backdrop of the mammalian visual processing system, we hope to also provide inspiration for future advances in automated visual processing.     

Text and non-text separation in offline document images: a survey

International Journal on Document Analysis and Recognition (IJDAR) - Separation of text and non-text is an essential processing step for any document analysis system. Therefore, it is important to...     

Effect of SiC Content on Mechanical and Tribological Properties of Al2024-SiC Composites

Silicon - Aluminium matrix composites are scientifically engineered materials possessing higher potential in automotive, aerospace and defence applications. Therefore this study focuses on the...     

Solar cells consisting of phenazine dyes in polymer matrix

We have constructed p−n heterojunction solar sandwich cells with phenazine dyes in a thin film of polyvinyl alcohol placed between a conducting glass coated with indium oxide and a platinum foil. The current-voltage relations of the cells have been measured in the dark and light under both forward and reverse biases.     

Highly dispersed platinum nanoparticles on graphitic carbon nitride: A highly active and durable electrocatalyst for oxidation of methanol,formic acid and formaldehyde

Finding efficient electrocatalyst for oxidation of small organic molecules such as methanol (CH₃OH), formic acid (HCOOH), formaldehyde (HCHO) etc. is essential for the development of their respective direct fuel cells. We report here highly dispersed platinum nanoparticles (PtNPs) on carbon nitride (CN_x) were successfully synthesized by the ultrasound mediated sodium borohydride reduction of H₂PtCl₆ in presence of CN_x nanosheets. This platinum–carbon nitride (Pt/CN_x) composite exhibited superior electrocatalytic activity towards oxidation of CH₃OH, HCOOH and HCHO in acid media. The mass activity, onset potential, tolerance to carbon monoxide (CO) poisoning and long term durability for the catalytic oxidation of CH₃OH, HCOOH, HCHO on Pt/CN_x catalyst in acid media is much higher than that of commercial Pt/C catalyst. The mass activity of Pt/CN_x catalyst at ～0.64 V (forward scan) is 310 mA/mg_Pt which is 2.7 time higher than that of commercial Pt/C for methanol oxidation. The electrooxidation of HCOOH on Pt/CN_x occurs via dual mechanism with greatly enhanced oxidation through dehydrogenation pathway in comparison with commercial Pt/C. The mass activity on Pt/CN_x at 0.3 V (vs. NHE) is 25 times higher than that of Pt/C for oxidation of HCOOH. The superior catalytic activity and durability of this Pt/CN_x catalyst can be attributed to high dispersion of PtNPs and strong catalyst support interaction.     

In vitro antioxidant activity of different cultivars of banana flower (Musa paradicicus L.) extracts available in India

Abstract: Six different cultivars of banana flowers (Musa paradicicus) (Kathali, Bichi, Shingapuri, Kacha, Champa, and Kalabou) were analyzed for the content of polyphenol expressed as gallic acid equivalent and flavonoid expressed as quercetein equivalent, and the in vitro total antioxidative activities of the flower extracts were compared with standard and expressed as trolox equivalent. The reducing power, 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) and 2,2‐azinobis(3‐ethylbenzothiazoline‐6‐sulfonic acid) radical cation (ABTS?⁺) scavenging activities, inhibition of lipid peroxidation in a linoleic acid emulsion system, and liposome peroxidation system were measured and compared with respective standard antioxidants. Iron‐mediated Fenton reaction was carried out to evaluate the protective effect of the extract of banana flower (Kacha cultivar) against H₂O₂‐induced DNA damage. The Kacha variety contains the maximum amount of polyphenol (11.94 ± 0.03 mg of gallic acid equivalent/g of dry weight) and flavonoid (0.174 ± 0.001 g of quercetin equivalent/g of polyphenol). It also has the highest total antioxidant capacity, DPPH radical scavenging activity, and ABTS?⁺ radical scavenging activity with a least EC₅₀ value of 0.051 mg/mL. Hepatic cell damage in iron‐mediated Fenton reaction caused by free radicals is reduced by the banana flower extract. On the basis of the results obtained, the banana flowers are found to be a potential source of natural antioxidants. This is the first report on the antioxidant properties of the extracts from banana flowers. The study suggests that the flowers of M. paradicicus that are found in India and consumed as vegetable can provide valuable functional ingredients that help in the prevention of oxidative stress.     

Kinetics of temperature-dependent photoinduced redox reactions in a photoelectrochemical cell

The effect of temperature on the electrode kinetics of photovoltage generation in photoelectrochemical (PEC) cells consisting of a phenazine dye-EDTA system, separated from an aqueous solution of an electron acceptor like iodine by a salt bridge has been studied. The phenazine dyes used are phenosafranin, safranin-O, and safranin-T. The maximum photovoltages (V_oc) generated and the sunlight engineering efficiency (SEE) have been found to increase with increasing temperature, but there is a fixed critical temperature for each dye above which the V_oc decreases: 29°C for phenosafranin, 35°C for safranin-T, and 40°C for safranin-O. The photovoltage growth and decay follow the functional forms related to the relaxation times. The rate constants for the forward and backward reactions have been calculated from these relaxation times at different temperatures. The rate of the photoinduced chemical reaction increases with an increase in temperature from 20°C–50°C for all the dyes, with concomitant decrease for the backward reaction. The free energies of electron transfer across the electrode/electrolyte interface have been calculated. The activation energies calculated from the rate constants at different temperatures for phenosafranin-EDTA, safranin-T-EDTA, and safranin-O-EDTA reactions are 5.14, 5.60, and 5.63 kJ mol⁻¹ respectively.