Publication

Underwater acoustic (UWA) channel is characterized as a severe multipath propagation channel due to signal reflections from the surface and bottom of the sea, that is affected by a variety of ambient noise profiles unique to underwater environment. Further the motion of water introduces a Doppler. Multicarrier modulation schemes can be adapted to meet a given Quality of service (QOS) in such environments. In this paper the underwater acoustic channel is studied using the Thorp and Ainslie-McColm models for absorption and their limitations are analyzed. Signal to noise ratio (SNR) profiles at various distances employing Discrete Multitone Modulation are obtained considering different types of ambient noise sources such as shipping, wind, thermal, bubble and turbulence. To meet the QOS different Rate Adaptive and Margin Adaptive Tone loading algorithms are simulated and compared based on system margin, utilizing these SNR profiles. � 2014 IEEE.

Nanoparticles of magnesium oxide (MgO) have been prepared by low temperature solution combustion and hydrothermal method respectively. Powder X-ray diffraction (PXRD) patterns of MgO samples prepared by both the methods show cubic phase. The Scanning Electron Microscopy (SEM) studies reveal, the combustion derived product show highly porous, foamy and fluffy in nature than hydrothermally derived sample. The optical absorption studies of MgO show surface defects in the range 250-300 nm. The absorption peak at ?290 nm might be due to F-centre. Photoluminescence (PL) studies were carried upon exciting at 290 nm. The sample prepared via combustion method show broad emission peak centred at ?395 nm in the bluish-violet (3.14 eV) region. However, in hydrothermal prepared sample show the emission peaks at 395 and 475 nm. These emission peaks were due to surface defects present in the sample since nanoparticles exhibits large surface to volume ratio and quantum confinement effect. � 2013 Elsevier B.V. All rights reserved.

This paper mainly deals with the target detection using orthogonal Polyphase Multiple Input Multiple Output (MIMO) radar waveforms against compound-Gaussian clutter with an unknown covariance matrix. The design of orthogonal code sets with correlation properties can effectively improve the radar performance by transmitting orthogonal waveforms optimized by Particle Swarm Optimization Algorithm (PSO). The space-time coding MIMO radar model has adopted, and developed to compound-Gaussian case. The GLRT is developed by assuming known covariance matrix, and then, a suitable estimate based on secondary data is inserted into the detector to make fully adaptive. The simulation results show that the orthogonal waveform and the GLRT used in MIMO radar Model can provide a good performance in spikier clutter. � 2013 The Authors. Published by Elsevier Ltd.

Till date, Tuberculosis is a major health problem especially in India. Though, Mycobacterium tuberculosis is the causative agent of tuberculosis (TB) and it kills approximately about 1.3 million people every year according to WHO, yet the role of complex microbial community favoring the growth of Mycobacterium complex is immense. There are several studies that have already been reported that there exists a strong association between the complex microbial interactions in the community and the disease condition for majority of the diseases that are caused by different microorganisms.Our present analysis aims to characterize up-till species level abundance in Mycobacterial tuberculosis metagenome. In our study we have taken a total of 100 whole genome sequenced Indian Tuberculosis patient samples. These 100 samples were analyzed to obtain taxonomical abundance. It was seen that South Indian samples had 54 unique species whereas North Indian samples had only 13 unique species. Our study revealed that Achromobacter, Nocardia, Chromobacterium, Staphylococcus, Xanthomonas, Bacillus, Sanguibacter and Bordetella are mostly abundant in Indian tuberculosis patients and we are able to classify all these till species level, which other 16s rRNA studies have failed to do. Knowing the species present during the tuberculosis infection it will be of great importance to treat the patients with right antibiotics for the microbiome present. � BEIESP.

In this paper, we provide the mixed generalized iterative method for scalar first order non-linear initial value problem, where the forcing function is the sum of increasing, decreasing, convex and concave functions. We develop the generalized iterative coupled lower and upper solutions of mixed type. Our method will yield generalized monotone method and generalized quasilinearization method as special cases. In these situations, we obtain linear and quadratic convergence respectively. In all other situations, we obtain super linear convergence. As an application, we provide some numerical results. � 2018 Author(s).