Performance Analysis of MSFRLS-VFF Based Real-Time Adaptive Noise Canceller with RLS and APA Algorithms Using TMS320C6713 Processor

Wireless Personal Communications - In this paper, the real-time adaptive noise canceller (ANC) system is implemented using modified sigmoid function variation based recursive least square with...     

A new feature extraction and classification mechanisms For EEG signal processing

Multidimensional Systems and Signal Processing - The Electroencephalogram (EEG) signal processing is one of the extensively used research field in recent days, in which the epileptic seizure...     

Ultra high gain CMOS Op-Amp design using self-cascoding and positive feedback

This paper presents an ultra high gain two stage CMOS Operational Amplifier which is designed using self-cascoding and positive feedback technique in order to provide gain enhancement. By comparing the circuit with other designed circuits it has been shown that applying positive feedback increases the gain of the Op-Amp without affecting other properties of the amplifier. The proposed circuit is designed in 45 nm technology using Cadence Virtuoso Analog Design Environment tool at ±1 V supply. The Op-Amp is designed to achieve a high gain of 141 dB while maintaining a UGB of 101 MHz and phase margin of 60°. The simulation results conforms the estimated theoretical improvements. The dependence of various properties such as slew rate, UGB, settling time and phase margin of the designed Op-Amp on compensating capacitor C_C has also been analyzed in this paper. Finally, the simulation results have been compared with a previously reported Op-Amp utilizing positive feedback technique.

     

Guest–host interaction in ferroelectric liquid crystal–nanoparticle composite system

The present paper deals with the characterization of a ferroelectric liquid crystal–nanoparticle (FLC–NP) composite system. The dielectric, electrical and polarization property of the FLC–NP composite system have been studied as a function of temperature and frequency. Ferroelectric Cu-doped ZnO (Cu–ZnO) nanoparticles have been added to the pure ferroelectric liquid crystal (FLC) Felix 17/100. The nanoparticles are bigger in size as compared to FLC molecules; therefore, they distort the existing geometry of FLC matrix and set up an antiparallel correlation with the dipole moments of the host FLC molecules. This antiparallel correlation of guest–host geometry reduces the net ferroelectricity of the composite system and modifies all the physical properties of the pure FLC. The change in properties has been analysed and explained in the light of guest–host interaction.     

On an f(R) theory of gravity based on non-conformal invariance of gravitational waves

Gravitational waves are an inevitable consequence of Einstein’s theory of gravitation, which are meaningfully comparable with electromagnetic waves except for their non-conformal invariance. So, Einstein’s field equations aremodified by a straightforward generalization of the Lagrangian in the Einstein-Hilbert action by choosing a polynomial in the scalar R of a finite number of terms. In this modified theory of gravity, conformally invariant gravitational waves are obtained. Besides this, cosmological aspects and the gravitational field surrounding a spherically symmetric mass distribution are studied to understand the features of this theory. It reveals that the deviations are not so significant at the observational level, and the features are more or less similar to those of Einstein’s theory.     

Design and synthesis of perfluorinated amphiphilic copolymers: Smart nanomicelles for theranostic applications

Since decades, varieties of amphiphilic polymers have been widely investigated for improving aqueous solubility and bioavailability of the hydrophobic drugs. The upcoming approach is to develop more efficient advanced nano-carrier molecules capable of more than drug delivery. Herein, we report the design and synthesis of some novel carrier molecules with multiple applications including drug encapsulation, drug delivery and diagnosis (imaging). Copolymers were synthesized using dimethyl 5-hydroxy/aminoisophthalate, poly(ethylene glycols) and Candida antarctica lipase (CAL-B, Novozym 435). CAL-B selectively catalyses the trans esterification reaction under solvent less condition using primary hydroxyls of poly(ethylene glycols) and leaving behind phenolic hydroxyl for post polymerization modifications. The obtained copolymers were further tethered with perfluorinated aliphatic chains to make them amphiphilic. The synthesized materials were investigated for their micellar behavior, temperature dependent stability (in aqueous solution), encapsulation capacity, and imaging potential by measuring the sensitivity of these perfluorinated materials towards ¹⁹F NMR in NMR tube. It was observed that perfluorinated amphiphilic copolymers could encapsulate up to 14% (by wt) of hydrophobic drug and showed decent ¹⁹F NMR signals even at a very low concentration. Therefore, these perfluorinated copolymers hold considerable potential for further investigation as advanced nano-carrier molecules for biomedical applications.     

A study on electromagnetic property during friction stir weld failure

Electromagnetic radiation is emitted during the transient stage of elastic to plastic deformation of metals and alloys. In the present work, aluminium plates were welded by friction stir welding (FSW) at different process parameters, such as tool rotational speed, traverse speed and rake angle. The EMR fundamental frequencies emitted during the tensile failure of the welds were measured and recorded. The variation in the fundamental frequency was analysed by fuzzy modelling using MATLAB and it was observed that an increase in the first mode of metal transfer decreases the fundamental frequency. Further, the fundamental frequency of a weld was estimated from the obtained model and found to be closer to the experimental results. This work will be more useful for metal flow analysis as well as online condition monitoring of the welds which are used in critical applications.     

Thermohydrodynamic analysis of infinitely wide cycloidal profiled pad thrust bearing with rough surface and a comparison to plane profiled pad

This work reports the thermal analysis of hydrodynamically lubricated cycloidal profiled pad thrust bearing (CPPTB) using an efficient numerical method based on Lobatto quadrature technique. The performance parameters with smooth and rough surfaces of cycloidal and plane profiled pads are presented for various operating inputs. Significant increase in magnitude of pressure and substantial reduction in coefficient of friction are observed in the presence of relatively large amplitude of roughness over the surface of stationary pads. Comparisons are made for performance parameters achieved with plane profiled pad thrust bearing (PPPTB) and CPPTB. The load carrying capacity of CPPTB is found significantly high than the PPPTB for the provided set of operating parameters. Copyright © 2008 John Wiley & Sons, Ltd.     

Isolation and Characterization of Phenanthrene-Degrading Bacteria from PAHs Contaminated Mangrove Sediment of Thane Creek in Mumbai,India

Polycyclic aromatic hydrocarbons (PAHs), including phenanthrene, are commonly found as pollutants in soils, estuarine, and sediments, as well as in terrestrial and other aquatic ecosystems. In this context, the phenanthrene-degrading bacteria were isolated and characterized in contaminated mangrove surface sediment, on the coast of Thane Creek, Mumbai, India by enrichment method, using phenanthrene as the sole source of carbon and energy. The phylogenetic diversity of the isolates were evaluated by 16S rRNA gene analysis and characterized as Bacillus mojavensis strain KSS001, Bacillus firmus strain KSS002, Bacillus flexus strain KSS003, Bacillus vietnamensis strain KSS004, and Bacillus amyloliquefaciens strain KSS005. Each isolate was grown on the phenanthrene up to 100 mg/L and the biodegradation ability was evidenced using a gas chromatography–flame ionization detector. Further, the mean value of phenanthrene degradation by 5 bacterial isolates after incubation in mineral salt medium for 7 days was 63% at 100 mg/L. The study reports that mangrove sediments of Thane Creek, Mumbai, contain a diverse population of phenanthrene-degrading bacteria that have the potential and capability to degrade PAHs contaminated sites, and are consequently recommended for bioremediation.