Indian Institute of Technology Bhubaneswar

About: Indian Institute of Technology Bhubaneswar is a education organization based out in Bhubaneswar, India. It is known for research contribution in the topics: Large Hadron Collider & Computer science. The organization has 1185 authors who have published 3132 publications receiving 48832 citations.

High aspect ZnO nanorod growth over electrodeposited tubes for photocatalytic degradation of EtBr dye

Abstract: In this work, vertically grown rod type ZnO nanostructures have been synthesized on metallic nickel tube films fabricated through the cost-effective process of electroforming. The use of tubular metal substrates for the growth of ZnO nanorods has been found to be advantageous for the photocatalytic degradation of EtBr dye because of their high surface area-to-volume ratio. The nickel tubes with ZnO nanorods were characterized using X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM). The developed system was utilized for the photocatalytic degradation of EtBr dye and its efficacy was revealed through the comprehensive mineralization of the dye within 150 min. The mechanism of the degradation process has been revealed through total organic carbon (TOC), chemical oxygen demand (COD) and high-performance liquid chromatography (HPLC) studies. A substantially lower amount of the photocatalyst has been used because of the homogeneously distributed growth of nanorods on the substrate. Density functional theory-based analysis has also been performed to study the photocatalytic degradation and adsorption properties of EtBr on ZnO nanorods. Using first principles DFT theory, geometry optimizations and vibrational analysis are performed which show a negative charge transfer from the substrate to the photocatalyst. For the first time this article reports the use of DFT analysis for investigating the adsorption of EtBr on ZnO nanorods, and the experimental growth of nanorods over electroformed Ni tubes.

A unified sparse signal decomposition and reconstruction framework for elimination of muscle artifacts from ECG signal

Abstract: Removal of muscle artifacts from the ECG signals is crucial for a reliable and accurate measurement of local features of ECG signals. In this paper, we present an automatic method for removal of muscle artifacts from ECG signals, based on four steps: decomposing ECG signal using sparse signal decomposition on mixed dictionaries; obtaining QRS complex signal; determining time-instants of R-peak; and removal of muscle artifacts from ECG signal. The noise reduction performance of the proposed method is tested and validated using ECG signals taken from a standard MIT-BIH Arrhythmia database. The reconstructed signals are assessed using both subjective quality assessment test and objective quality assessment metrics. Performance evaluation results show that the proposed method outperforms other existing ECG denoising methods inadequately removing the muscle artifacts without significantly distorting the morphologies of P-wave, QRS-complex and T-wave of the ECG signals.

On-Device Integrated PPG Quality Assessment and Sensor Disconnection/Saturation Detection System for IoT Health Monitoring

Abstract: In this article, we propose a new on-device photoplethysmography (PPG) signal quality assessment (SQA) system based on the first-order (FO) predictor coefficient (PC) of differenced sensor (DS) signal that is capable of significantly reducing false alarms and timely notifying sensor disconnection and saturation in unsupervised health monitoring. The proposed system consists of the DS signal computation, random noise addition, PC estimation, and hierarchical decision rules. The proposed system is evaluated by using varieties of sensor signals taken from standard databases and the PPG signals recorded using three PPG sensing modules available at our Biomedical System Laboratory. Results show that the proposed method achieves correct detection rates of 98.22%, 80.09%, and 99.79% for noise-free PPG segments, motion artifacts corrupted segments, and pulse-free segments, respectively, and also outperforms other SQA methods. The proposed method had a false alarm reduction rate of 90.71% and a missed acceptable quality rate of 1.78%. Real-time implementation on the Arduino Due computing platform with a 32-bit Cortex-M3 processor, 512-kB flash memory, and 96-kB data memory demonstrates that the proposed on-device SQA system consumes 0.141 mJ with an overall accuracy of 93.21%, whereas the kurtosis and Shannon entropy (KSE) and the fiducial and template (FT)-based methods consume 109.08 and 6.71 mJ with overall accuracies of 39.24% and 74.13%, respectively. The proposed system has great potential for developing energy-efficient accurate and reliable Internet of Things (IoT) and smartphone-based health monitoring systems.

Synthesis of reduced graphene oxide nanosheet-supported agglomerated cobalt oxide nanoparticles and their enhanced electron field emission properties

Abstract: In this work, the field emission properties were demonstrated of reduced graphene oxide nanosheets (rGO-NSs) containing agglomerated Co3O4 nanoparticles (rGO–Co3O4) synthesized by a one-step microwave approach. Structural investigation indicates that the as-synthesized rGO–Co3O4 composite contains agglomerated Co3O4 nanoparticles on the surface of rGO-NSs. The field emission properties of the rGO–Co3O4 composite were investigated. The results indicate that the rGO–Co3O4 composite has excellent field emission performance, with turn-on field of 2.6 V μm−1, threshold field of 3.1 V μm−1, and a field enhancement factor of 3161.8. Furthermore, the emission current shows stability over 400 min of continuous operation. The synthesized rGO–Co3O4 composite has potential for application in field emission devices. This enhancement of field emission properties was investigated based on the surface morphology of the self-assembled nanostructures.

Studies on water absorption behaviour of bamboo–epoxy composite filled with cenosphere

Abstract: This paper deals with the evaluation of water absorption properties of natural fibre composites consisting of bamboo fibre as reinforcement, epoxy as matrix and cenosphere as particulate filler at different environmental conditions. Hand lay-up technique is used to fabricate the composites with varying number of layers of bamboo fibre and cenosphere filler content. Water absorption kinetics of the composites is presented in this paper. It is observed that the rate of water absorption depends on the fibre content as well as filler content. Addition of filler in the layered bamboo–epoxy composite decreases the moisture absorption capacity and maximum reduction is observed to be 21% and 32% for distilled and sea water conditions, respectively, in seven-layered composite with 3.0 wt% filler.