Dynamic video anomaly detection and localization using sparse denoising autoencoders

The emergence of novel techniques for automatic anomaly detection in surveillance videos has significantly reduced the burden of manual processing of large, continuous video streams. However, existing anomaly detection systems suffer from a high false-positive rate and also, are not real-time, which makes them practically redundant. Furthermore, their predefined feature selection techniques limit their application to specific cases. To overcome these shortcomings, a dynamic anomaly detection and localization system is proposed, which uses deep learning to automatically learn relevant features. In this technique, each video is represented as a group of cubic patches for identifying local and global anomalies. A unique sparse denoising autoencoder architecture is used, that significantly reduced the computation time and the number of false positives in frame-level anomaly detection by more than 2.5%. Experimental analysis on two benchmark data sets - UMN dataset and UCSD Pedestrian dataset, show that our algorithm outperforms the state-of-the-art models in terms of false positive rate, while also showing a significant reduction in computation time.     

Au/SnO2 an excellent material for room temperature carbon monoxide sensing

Tin dioxide synthesized by the hydrothermal method, impregnated with Au has been used for the room temperature carbon monoxide sensing in air. Incorporation of poly ethylene glycol (PEG-6000) as a modifier during the synthesis procedure results in well dispersed nanosized particles of SnO₂ which influence the sensing capability dramatically. This tailored morphology leads to development of a material with improved sensor response. Incorporation of gold resulted in a composition that was capable of selectively sensing low concentrations (upto 10 ppm CO in air) at temperatures below 50 °C. The mechanism of improved sensing has been explained based on the gas sensing characteristics with support from TEM, UV-DRS, XPS and FTIR.     

Carbon microtubes: tuning internal diameters and conical angles

In this paper, we report a synthesis strategy for a new class of hollow, curved carbon morphologies, 'carbon microtubes' (CMTs), with absolute control over their conical angles and internal diameters. Our synthesis methodology employs nitrogen or oxygen dosing to change the wetting behaviour of gallium metal with the growing carbon walls to tune the conical angles. Increasing N(2) concentrations in the gas phase during growth increases the conical angles of CMTs from +25° to about -20°. A methodology using the timing of oxygen or nitrogen dosing during CMT growth is shown to tune the internal diameters anywhere from a few nanometres to a few microns. The walls of the carbon microtubes are characterized using transmission electron microscopy (TEM) and Raman spectroscopy and are found to consist of aligned graphite nanocrystals (2-5?nm in size). Furthermore, dark field images of CMTs showed that the graphite nanocrystals are aligned with their c-axes perpendicular to the wall surface and that the crystals themselves are oriented with respect to the wall surface depending upon the conical angle of the CMT.     

Electrical and Electromagnetic Interference (EMI) shielding properties of hexagonal boron nitride nanoparticles reinforced polyvinylidene fluoride nanocomposite films

The hexagonal boron nitride nanoparticles (h-BNNPs) reinforced flexible polyvinylidene fluoride (PVDF) nanocomposite films were prepared via a simple and versatile solution casting method. The morphological, thermal and electrical properties of h-BNNPs/PVDF nanocomposite films were elucidated. The electromagnetic interference (EMI) shielding properties of prepared nanocomposite films were investigated in the X-band frequency regime (8–12 GHz). The EMI shielding effectiveness (SE) was increased from 1 dB for the PVDF film to 11.21 dB for the h-BNNPs/PVDF nanocomposite film containing 25 wt% h-BNNPs loading. The results suggest that h-BNNPs/PVDF nanocomposite films can be used as lightweight and low-cost EMI shielding materials.     

Investigation of Relationship Between Blend Ratio and Yarn Twist on Yarn Properties of Bamboo,Cotton, Polyester,and its Blends

In this study, a series of blended yarns consisting of 80:20 bamboo/cotton, 67:33 bamboo/cotton, 50:50 bamboo/cotton, 33:67 bamboo/cotton, 20:80 bamboo/cotton, 80:20 bamboo/polyester, 67:33 bamboo/polyester, 50:50 bamboo/polyester, 33:67 bamboo/polyester, and 20:80 bamboo/polyester were produced from blends consisting of bamboo/cotton and bamboo/polyester. Besides these, 100% bamboo, 100% cotton, and 100% polyester were also produced. All the yarns were produced with two levels of twist per meter (TPM) 76 and 90. It can be found that the yarn unevenness characteristic was affected by the blended ratio of cotton, polyester, and regenerated bamboo fiber. The drop in tenacity of blended yarns in comparison to the constituents is generally lower which is attributed to the elongation at break of the yarns. The variability in tenacity in respect of 100% polyester yarn is quite high in comparison with other yarns. The yarn elongation at break of bamboo/cotton-blended yarns is found to be lower than those of bamboo/polyester-blended yarns. The variability in the work of rupture is found to be lower for bamboo/cotton-blended yarns. Yarn friction values of the yarns noticed that polyester exhibits the highest value at the TPM of 76. The yarn torque values from which it is noticed that 100% polyester yarns spun with the TPM of 76 have a higher torque in both the wet and dry states. The quality characters of yarn depend upon the ratio of bamboo, cotton, and polyester in the blend ratio.     

Automated image processing for grain boundary analysis

The image processing used in the automated analysis of grain boundaries and triple junctions in scanning electron microscopy images is described. The required image processing includes the location of grain boundaries and triple junctions, calculation of the dihedral angles at triple junctions, and selection of electron backscatter probe points (to obtain grain orientation data).     

Refolding of β-galactosidase: microfluidic device for reagent metering and mixing and quantification of refolding yield

We have developed a device that uses microfluidic valves and pumps to meter reagents for subsequent mixing with application to refolding of the protein β-galactosidase. The microfluidic approach offers the potential advantages of automation, cost-effectiveness, compatibility with optical detection, and reduction in sample volumes as opposed to conventional techniques of hand-pipetting or using robotic systems. The device is a multi-layered poly(dimethylsiloxane) on glass device with automated controls for reagent aliquoting and mixing. Refolding experiments have been performed off-chip using existing protocols on the protein β-galactosidase and the refolding yield has been quantified on-chip using fluorescein di-β-d-galactopyranoside, a caged-fluorescent molecule. This work provides the potential to reduce the cost of drug discovery and realization of protein pharmaceuticals.