Informatics Publishing Limited

S. Lakshmi Narayana ¹, J. Suneetha Devi ¹, I. Bhargav Reddy ¹, P. Harish ¹

Affiliations
1 Department of ECE, KL University, Vijayawada, A.P, IN

Abstract

Voice recognition is a process of recognizing a person on the basis of their speech sample. This paper describes various techniques that are used for voice recognition in order to optimize the recognition rate. The different techniques that are described in this paper are Linear Predictive Coding (LPC), Neural Networks (NN), Mel Frequency Cepstrum Coefficients (MFCC), Vector quantization (VQ), Euclidean Distance. MFCC and LPC are used to extract speaker specific characteristics from voice signal. Neural Networks and Euclidean Distance are used for matching the characteristics extracted using MFCC and LPC. The recognition rates are calculated in each method and they are compared. Mel Frequency Cepstrum Coefficients gives better recognition rate when compared with the other two techniques. Various other approaches for implementing voice recognition are Hidden Markov Modeling (HMM), Gaussian Mixture Modeling (GMM), and Dynamic Time Warping etc. The Voice Recognition system has potential applications in various fields. Some of them are access control to computers, telephone banking, forensics, speech recognition etc.

Keywords

Linear Predictive Coding (LPC), Mel Frequency Cepstral Coefficients (MFCC), Neural Networks( NN), Vector Quantization (VQ).

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P. Harish ¹, M. Palanivelan ², Sheila Anand ³

Affiliations
1 Department of Communication Systems, Rajalakshmi Engineering College, Chennai, IN
2 Department of ECE, Rajalakshmi Engineering College, Chennai, IN
3 Rajalakshmi Engineering College, Chennai, IN

Abstract

Orthogonal Frequency Division Multiplexing (OFDM) is one of the attractive technology for wireless communications with Multi-Carrier Modulation (MCM) technique offers a considerable multipath delay spread tolerance, high spectral efficiency, immunity to the frequency selective fading channels and power efficiency. High Peak-to-Average Power Ratio (PAPR) of the transmit signal is a major drawback of multicarrier transmission such as OFDM. Partial Transmit Sequence (PTS) is one of the commonly used schemes to reduce the PAPR. Conventional Partial Transmit Sequence (C-PTS) requires an exhaustive searching over all combinations of the given phase factors, which results in exponential increase to the computational complexity with the number of sub blocks. In this paper, we aim to obtain the desirable PAPR reduction with the low computational and phase search complexity. PTS based phase weighting techniques with low computational complexity, named Segmented Phase Weighting (SPW) and Iterative Phase Weighting (IPW), are proposed. On applying one of the linear transformation techniques called circular time shift to the candidate sequences obtained by SPW and IPW method, high PAPR reduction can be obtained. This system will slightly increase the computational complexity but greater reduction in PAPR. At the receiver, by utilizing the natural diversity of phase constellation for different candidates, the detector can successfully recover the original signal without Side Information (SI). PAPR reduction performance of both proposed schemes are analyzed, the simulation results show that the proposed Circular Time Shifted- Segmented Phase Weighting (CTS-SPW) and Circular Time Shifted- Iterative Phase Weighting (CTS-IPW) schemes achieve better PAPR reduction compared to the C-PTS scheme.

Keywords

Iterative Phase Weighting (IPW), Orthogonal Frequency Division Multiplexing (OFDM), Peak-to-Average Power Ratio (PAPR), Segmented Phase Weighting (SPW).

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Damarla Paradhasaradhi ¹, K. Satya Priya ¹, K. Sabarish ¹, P. Harish ¹, G. V. Narasimharao ¹

Affiliations
1 Department of Electronics and Communications Engineering, K L University, Guntur – 522502, Andhra Pradesh, IN

Abstract

Background/Objectives: This paper represents the implementation of carry look ahead adder using different leakage power reduction techniques like sleepy approach, stack approach, sleepy stack approach and sleepy keeper approach. Effecting the static power dissipation high, the threshold voltage (Vth) is reduced that has granted tremendously towards the growth in the sub threshold leakage power. Here conventional 4-bit carry look ahead adder is designed by adopting 1-bit full adders and carry look ahead blocks. Methods/Statistical Analysis: In this paper, an extensive study and analysis of different leakage power minimization approaches have been implemented. In the comparative analysis carry look ahead adder is designed using different leakage power reduction approaches like sleepy, stack, sleepy stack and sleepy keeper. The circuits are implemented on Tanner EDA tool at 250 nm Technology and considered PMOS, NMOS as typical models. From this paper work that only an applicable selection of leakage power reduction approach for a particular function will be well borne by a Very Large Scale Integrated (VLSI) circuit design depend on progressive analytical method. Findings: The average power, delay and number of transistors are calculated in the tanner tool for carry look ahead adder using all the four approaches. Applications/Improvements: The analytical study is implemented in the real time applications while constructing adders.

Keywords

Conventional CMOS, Leakage Power, Power Dissipation, Reduction Technique, Sleepy Keeper.

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B. Babu Rao ¹, P. Harish ¹, Saikat Das ¹, T. Ashwin Kumar ¹, V. Raman Koundinya ¹

Affiliations
1 Pathfinder Institute of Pharmacy Education and Research, Beside Mamnoor Camp, Warangal-506166, IN

Abstract

The objective of the present work was to prepare and evaluate extended release matrix tablets of Losartan potassium. Losartan potassium, an Angiotensin receptor blocker used in the treatment of hypertension, has poor bioavailability (33%) and has elimination half-life of 2 hrs. So, it is best suited for extended release matrix formulation. The tablets were formulated to reduce the frequency of dose administration and to improve the patient compliance. Tablets were prepared by direct compression method, using hydrophilic polymers like natural (Xanthan gum, Guar gum) and synthetic (HPMC K100 M) as the release retarding polymers. The FTIR studies indicated the absence of drug polymer interaction. The formulated tablets were evaluated for weight variation, hardness, friability, drug content uniformity and swelling index. The In Vitro drug release of the tablets was carried out in pH 6.8 buffer for 24 hrs. The influence of different polymers like Xanthan gum, Guar gum and HPMC K100 M as well as their combinations on the drug release profile was studied. Based on the dissolution studies optimised formulae are F-12 and F-14. To analyze the mechanism of drug release from the tablets, the In-Vitro dissolution data of optimised formulations were fitted to zero order, first order, higuchi release model and korsmeyer-peppas model based on regression coefficient. The n values of the optimised formulations F-12 and F-14 were 0.585 and 0.599 respectively. This indicates the release of drug followed Non Fickian or anomalous transport.

Keywords

Extended Release, Losartan Potassium, Hydrophilic Polymer.

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