Electrical and Electronics

A two stage novel speech enhancement algorithm is presented in this paper. First stage is designed such that it can substantially improve the signal to residual spectrum ratio by combining statistical estimators of the spectral magnitude of the speech and noise. By expressing the signal to residual spectrum ratio as a function of the estimators gain function. We derive a hybrid strategy that can improve the signal to residual spectrum ratio when the apriori and the posteriori SNR are detected to the lower than 0dB. The enhanced signals still suffer from undesirable speech distortion due to harmonic distortion. Some harmonics are considered as noise only components and are suppressed. To overcome harmonic distortion introduced in enhanced speech, in the proposed method the suppressed harmonics are regenerated. Objective and subjective tests were carried out to demonstrate improvement in the perceptual quality of speeches by the proposed technique.

Zinc Ferrite (ZF) is a material that is paramagnetic. Its presence in the universe has a magnetic force that is different depending on the structure and composition of materials. In some cases look almost the same, especially on substances ZF reacted at temperatures between 60 0C to 90 0C. ZF 70 have weaknesses at a temperature of 70, which is where most low coercivity alternating magnetism.

Interpolation is the process of enlargement of images which is used in modern era of communication system to get highly magnified best quality image. In this paper, different types of interpolation algorithms are presented, out of which Bicubic method exceeds all other methods as it eradicates the blurr and stair shaped edges, which were generated when all other interpolation algorithms were applied. Hence it is highly recommended in various Image processing based applications like Satellite Navigation, Television Broadcasting, Computer Graphics, Special Effects etc.

This paper deals with series connection of stator windings and with decoupled dynamic control, it has been introduced recently. The two-motor drive system is supplied from a single five-phase voltage source inverter (VSI) and the machines are controlled using vector control scheme. In literature this drive configuration utilizes current control in the stationary reference frame so current fed machine models are employed and the current regulated PWM multi-phase inverter replicates the current references. If current control is to be implemented in the rotating reference frame, a PWM method for the five-phase VSI is needed to generate required reference voltages. This paper proposes voltage modulation scheme to generate five-phase inverter output signals using a simple approach, in such a way that independent and decoupled control of two five-phase series-connected machines is achieved with minimum interaction between the two machines. The proposed method offers significant advantages over the existing space vector PWM. The suggested method generates output voltages that contain two fundamentals at operating frequencies required by the two machines with reduced computational burden on digital signal processor (DSP). The concept is verified by simulation and experimental approach.

IEEE 802.16 family of standards (also known as WiMAX) is a broadband wireless access technology that is designed to offer high-speed connectivity. Broadband access to Internet is currently dominated by wired technologies like DSL and cable. WiMAX technology provides wireless alternative to broadband access and need to support various Internet traffics and applications. In this paper focus is to simulate and transfer of different traffics with different error correction techniques implemented in MAC layer and provides the comparative analysis of the throughput and end-to-end delay characteristics. Channel error rate is varied to observe the performance differences. Simulation results show that the error control techniques at MAC layer provides substantial improvements in end-to-end throughput and delay characteristics at lower error rates. Hybrid ARQ mechanism outperformed all other error control schemes even at significantly high error rates.

The combo of coding with spatial assorted qualities opens up new measurements in wireless interchanges, and can offer successful answers for the difficulties confronted in acknowledging solid rapid connections. Use of Space-Time Block Coding (STBC) with Multiple-Input Multiple-Output (MIMO) set-up proves to be an efficient method for this task. In wireless environment there is no prior knowledge of the channel state information (CSI) and hence it is required to employ some estimation techniques to obtain an estimate of the channel. Channel estimation is thus an important step in receiver design. Multiple Input Multiple Output (MIMO) is a promising candidate for the upcoming generation communication networks. It has been proposed to develop wireless systems that offer both high capability and good performance. To accomplish high date rate and ful?ll the power, MIMO systems are equipped with High Power Ampli?er (HPA). Unfortunately, the nonlinearity of HPA has a crucial impact and affects the receiver’s performance. Due to the high bandwidth utilization efficiency, multiple-input multiple-output orthogonal frequency-division multiplexing (MIMO-OFDM) techniques have become a major trend for modern communications. However, MIMO-OFDM techniques need exact synchronization and channel estimation methods to compensate the frequency offset and utilize the multiple antenna diversity.

In this Paper the comparison between two traction motors i.e. Permanent magnet synchronous motor and three phase Induction motor has been done to find out the best traction motor suitable for electric vehicle application. First the sizing of vehicle parameters is done to find the rated torque, speed and power suitable to design a three phase induction motor. In Matlab simulation, the Simulink model of Fuel cell Electric vehicle using New York city drive cycle is run with two different motors .The simulation result is obtained with two types of controllers i.e. PID and Fuzzy controller and the simulation results show that Fuzzy controller gives better control characteristics.

Wiener systems identification is studied in the presence of possibly infinite-order linear dynamics and nonparametric nonlinear element. The latter can be noninvertible and of arbitrary-shape. Using simple constant and sine excitations, and getting benefit from model plurality, the problem identification problem is made. All estimators are shown to be consistent

There are lots of nonlinear formulas in mathematics and physics and there are, many types of solitons to talk over. This revision is dedicated to the straight technical particulars of how to produce soliton solution of Maxwell's equations and intensive confirmation is placed on mathematical report analysis. The quasi-stationary state waveguides has been founded and with a small deviation from equilibrium, we measured and advanced a solution for a formula. Classical parting of parameters is presented with a special B.C. is introduced on a slab waveguide to obtain a general form of solution of the coordinates x, y z.

Flexible AC Transmission Systems (FACTS) play a major role in controlling the load flow in the power system. In this paper, reactive power control is performed with STATCOM based on the fuzzy controller. The purpose of using the fuzzy controller is to improve the STATCOM performance for continuous and fast reactive power control. The performance of the STATCOM based fuzzy controller in a 14-bus test system with simulation is evaluated by MATLAB/SIMULINK software. Also, a control component to limit STATCOM's reactive power at level of nominal power is used to prevent damage. The simulation results will show the optimal performance of the fuzzy controller and the limiter.