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The Thesis contains a multicasting synopsis in wireless multicasting system through Rayleigh fading channel, where a source transmitter interfaces with multiple users where multiple eavesdroppers are present, multiple antennas are attached on both the receivers of users and eavesdroppers. All the eavesdroppers are independent mutually. When no eavesdropper eavesdropped, then information is secured. Here a consideration is made that source and clients receivers communicate through multiple relays. Considering zero-forcing (ZF) filtering in the system of multiplexing, the expressions related to closed-form for the ergodic secrecy multicast capacity, eavesdropper capacity and ergodic secrecy multicast capacity is derived to scrutinize the accomplishment of propound model. Paper contains multicasting and security at the same time.

‘III-nitride’ semiconductor based light emitting diodes (LEDs) have completely transformed the lighting industry due to its unique optical and electrical properties, which leads to higher efficiency and brightness. However, electron leakages, poor hole injection, and efficiency droop significantly affect the electrical and optical properties of InGaN/GaN LEDs that leads to the poor power conversion efficiency. These problems can be effectively minimized by introducing an Electron Blocking Layer (EBL) in conventional LEDs. The objective of this work is to investigate the effect of EBL layer (i.e., Al x Ga l-x N) on dual wavelength InGaN/GaN LEDs with different Al compositions (x). Different compositions of AlxGal-xN have been used to study the electrical and optical properties of LEDs and find out their optimal design parameters by using APSYS simulation program. The simulation results suggested that the composition of Al of the EBL and properties of quantum well has significant effects on the optical and electrical properties of InGaN/GaN LEDs. The gradually increasing composition (from $x$ = 0 to 0.13) of the EBL shows large output power from the LED as it significantly reduces the electrons leakages of the device.

Fibromyalgia syndrome which is appeared in the form of common pain in women is a musculoskeletal disorder. Heart rate variability (HRV) is a signal as measured time between each successive QRS time obtained from ECG signal. HRV parameters are associated with autonomic nervous system in literature. FMS affects patient's psychology. Consequently some psychological tests are applied to patients for evaluation of psychological effects. Beck Anxiety Inventory (BAI) Test being applied as writing and speaking is a test consisting of 21 questions. In the study, HRV signals obtained from FMS patients and control group are decomposed into wavelet packets using Wavelet Packet Transform (WPT) and frequency bands which related to autonomic nervous system are included to study. Wavelet Packets within these frequency bands are applied to inputs of multilayer perceptron artificial neural networks (MLPNN). BAI psychological test scores are included as target values for MLPNN and each input is trained and tested as relating to target values. According to obtained accuracy values, the packets within Very Low Frequency (VLF) band has minimum accuracy values, however the packets within Low Frequency + High Frequency (LF+HF) has the best accuracy values. This study is targeted on presenting a solution for clinical studies which are evaluated using psychological test scores by physiological support.