This dissertation is explored the photonics inter sub band transitions (ISBT) phenomenon in an electronics Gallium Nitride (GaN) high electron mobility transistor (HEMT) device. Conventional photonic devices are operated at cryogenic temperatures to minimize the thermal effect. The reported maximum operating temperature of THz quantum cascade laser (QCL) is in the range of 150-200 K which is too low for general applications. The conduction band tuning through external gate bias makes advantage of HEMT device for room temperature (RT) terahertz applications.

This study is an earnest attempt to understand the role of mass media in the transition of Adivasis in the Wayanad District of Kerala. It was designed to address certain intriguing questions that emerged in the researcher’s mind, ranging from when the media technologies made inroads into the life of the Adivasi communities, what are the media artefacts that have got diffused, what are the different factors that have influenced the diffusion of mass media among Adivasis and how they have influenced the everyday life.

A systematic, extensive and in-depth study of channel characteristics for both static and dynamic human body model is reported in this thesis. The work involves design, fabrication and testing of various printed and dielectric antennas with very high gain for the proposed applications. A significant part of the thesis deals with human model which features the critical body segments such as head, shoulder, torso, upper arm, lower arm, thighs and calf for the study of double arm swing activity.

We begin our work by studying the most general class of oscillators, called ‘f-deformed oscillators’ or ‘f-oscillators’. We define the quadrature operator for the f-deformed algebra and hence obtain the deformed quadrature operator eigenstates. We derived a new set of polynomials and derived the deformed oscillator wavefunctions in terms of them. The position probability distribution for three different types of deformations are plotted, and each is compared with the corresponding non-deformed counterpart.

The eco-cultural space Kavu (sacred groves) has been subjected to academic introspe

Experiments probing correlations between spin-1/2 nuclei (I) and nuclear spins (S) with large anisotropic interactions (quadrupolar or chemical shift anisotropy ) often offer valuable access routes to molecular structures and dynamics. In such experiments, development of efficient correlation schemes is not trivial and constitutes an ever-evolving theme of research.

The work presented in this thesis is a theoretical and numerical investigation of the spin- dynamics in two recently demonstrated experiments involving long periods of RF irradiation on the quadrupolar nuclei channel, the 1 H - 14N double cross polarization (double CP) under fast MAS experiment by Carnevale et al. and the 1H - 35Cl TRAPDOR-HMQC experiment of Hung et al. Creation and evolution of various coherences generated in these proton-detected experiments are explored.

The work is on Dynamic Compressed Sensing (DCS) system for efficient acquisition and recovery of sparse and compressible time-varying signals. DCS has three key components to be addressed: Estimation of the Sparsity level, indices of those sparse basis functions and their amplitudes. Sparsity Order Estimation (SOE) algorithms based on both Bernoulli/Gaussian sensing matrices and optimal tracking algorithms such as the Kalman filter and Viterbi Algorithm were developed.

Processing of powders to ceramic components uses a large number of interim additives such as solvents, binders, plasticizers, dispersants, lubricants, and coagulating agents. The majority of these processing additives are synthetically prepared from petroleum-based chemicals. Sustainable development necessitates the replacement of these synthetically prepared additives with naturally renewable materials. The thesis explores the use of natural rubber latex as a binder, gelling agent, and pore stabilizer for the preparation of dense and porous alumina ceramics.

Perchlorate contamination in water due to industrial and space activities remains a serious problem as it seriously affects the function of thyroid glands. Various methods are being explored for the removal of perchlorate from the contaminated water. Among them, adsorption is a simple and cost-effective technique. The development of efficient adsorbent materials is the key to the success of the adsorption method of perchlorate removal. This thesis explores the synthesis of magnetically functionalized novel adsorbent materials from bio-waste such as eggshell and watermelon rind.