Fpga Based Improved Stator Flux and Torque Estimators For Direct Torque Control Of Induction Motor Drive System

Year: 2011

Issue: September-November        

Title: Fpga Based Improved Stator Flux and Torque Estimators For Direct Torque Control Of Induction Motor Drive System 

Author Name: R. Rajendran, N. Devarajan 

Synopsis: 

This paper presents an improved FPGA based stator flux and torque estimators for direct torque control of induction motor drive. In voltage model -based of stator flux estimation, a low pass (LP) filter is normally used instead of a pure integrator to avoid integration drift problem due to DC off-set, noise and measurement error present in the back electromotive force (emf).In steady state condition, the LP filter estimator will degrade the performance and efficiency of the induction motor drive system since it introduced magnitude and phase errors. A simple method is proposed to improve the steady state performances of the drive system. MATLAB/SIMULINK and Xilinx System Generator tools are used to model and view the functionality of the proposed system.

Semiconducting - Carbon Nanotube Field Effect Transistor Based Logic Gates

Vol.1 No. 4
Year: 2011

Issue: June-August

Title: Semiconducting - Carbon Nanotube Field Effect Transistor Based Logic Gates 

Author Name: V. Saravanan, V. Kannan 

Synopsis: 

Carbon Nanotube Field Effect Transistors (CNTFET) are new  nano-scaled devices for the digital circuits. In MOSFET based digital circuits when the channel length is much smaller than a micrometre is a challenge, and creates the problems in device fabrication, which limits advancing the integrated circuit. Small size of the MOSFET, below a few tens of nanometres creates the low Trans-conductance, gate oxide leakage, low ON-current, Mobility degradation and increased delay. Problems observed in the MOSFET, when size is reduced are avoided in CNTFET, since in case of CNTFET, carbon nanotube is used as channel and high-k material is used as gate dielectric. In this paper, we present the simulation results of semi-conducting Carbon Nanotube Field Effect Transistors based logic gates using HSPICE.

  

An Approach for Real Time Audio Watermarking Using Wavetable Alternation in Digital Instruments

Vol.1 No. 4
Year: 2011

Issue: June-August

Title: An Approach for Real Time Audio Watermarking Using Wavetable Alternation in Digital Instruments 

Author Name: M. Vadivel, V. Saravanan 

Synopsis: 

Musical performance with digital instruments has become a common practice today and many digital instruments came to be used in Desk Top Music, live performance, etc. However, the spread of digital contents causes the problem of illegal duplication and distribution, so that digital watermark has recently attracted much attention as a technology to solve this problem. In this project we focus on a sound synthesized process in digital instruments and propose a real-time watermark method. Certain watermarks are embedded in wavetables that include in our digital instruments and the insertion of secret messages is actualized with wave table switching additionally embedded watermarks can be extracted from the acoustic signal. The proposed method is able to achieve a real-time watermark.

In-Vehicle Real-Time Human Emotion Recognition through Visual, Thermal and Heart Rate Monitoring Using Parallel CPU and GPU Techniques for Driver Safety

Vol.1 No. 4
Year: 2011

Issue: June-August

Title: In-Vehicle Real-Time Human Emotion Recognition through Visual, Thermal and Heart Rate Monitoring Using Parallel CPU and GPU Techniques for Driver Safety 

Author Name: Goh Chia Chieh, Dino Isa 

Synopsis: 

Real-Time Human Emotion Recognition Is A Challenging Task. Speed And Accuracy Has Always Been The Main Concern For Human Emotion Analysis. Such System Poses An Even Greater Challenge For Implementation In A Limited Space Of A Constantly Mobile Environment, For Example, In A Moving Vehicle. On Top Of That, Power Consumption Is Another Major Issue To Be Considered. This Paper Proposes An Efficient Method On How Such System Can Be Implemented In The Mobile Environment By Utilizing Parallel Cpu And Gpu To Achieve Real-Time Emotion Analysis And Judgment. Using Low Power Consumption Single Board Computer (Sbc) With A Dual Graphic Card Installed, The Task Will Be Split Into Multiple Threads Which Process Visual, Thermal And Heart Rate Emotion Monitoring System Simultaneously. Thus, Better Accuracy And Optimal Performance Is Attained Through Parallel Gpu And Cpu Processing. Handling Enormous Of Data Through Parallel Processing Requires Expertise In Combining The Cpu And Gpu Tasks Together By Merging Different Kinds Of Data Competently.

    

 

   

 

     

Study of the Voltage Stability in a Multibus Power Network Using Ai Technique

Vol.1 No. 4

Year: 2011

Issue: June-August

Title: Study of the Voltage Stability in a Multibus Power Network Using Ai Technique 

Author Name: G Prasad, D. Vijay Kumar, M. Ebraheem, A. Muneiah 

Synopsis: 

Voltage instability is a state of power system encountering an unacceptable voltage level. This paper describes the expressions of Fast Voltage Stability Index (FVSI) and Line Quality Factor (LQF), which may be considered as indication of voltage collapse under constrained condition of an interconnected power system. Artificial Neural Network Technique has been applied to identify the voltage collapse condition. The novelty of this method is that, once the ANN model of the system is developed, through on line checking of the load of the weak bus, the present method can immediately calculate the FVSI and LQF without going through the complex classical calculations. The developed ANN technique has been tested in IEEE 30 bus test system and is found to be in excellent agreement with the result obtained by classical method.

   

 

   

 

     

Empirical mode decomposition of Atmospheric radar signals

Vol.1 No. 4

Year: 2011

Issue: June-August

Title: Empirical mode decomposition of Atmospheric radar signals 

Author Name: Padmaja Nimmagadda, S. Varadarajan, G. Madhavi Latha 

Synopsis: 

In this paper, comparison study of wavelet transforms and Empirical mode decomposition (EMD) was performed for two sets of atmospheric radar data. Wavelets and EMD has been applied to the time series data obtained from the mesosphere-stratosphere-troposphere (MST) region near Gadanki, Tirupati.  Wavelet analysis is one of the most important methods for removing noise and extracting signal from any data. The de-noising application of the wavelets has been used in spectrum cleaning of the atmospheric signals. EMD is a numerical sifting process to decompose a signal into its fundamental intrinsic oscillatory modes, namely intrinsic mode functions (IMFs).  A series of IMFs can be obtained after the application of EMD. The Algorithm is developed and tested using Matlab. Analysis has brought out some of the characteristic features such as Doppler width, SNR of the atmospheric signals. The results showed that the proposed algorithm is efficient for dealing non-linear and non- stationary signals contaminated with noise.  SNR using wavelets and EMD has been compared and plotted for validation of the proposed algorithm. EMD is found to be effective in removing the noise embedded in radar echoes.

  

 

   

 

     

Non-linear Analysis of the Cardiovascular System (Vanderpol oscillator) using Simulink

Vol.1 No. 4
Year: 2011

Issue: June-August

Title: Non-linear Analysis of the Cardiovascular System (Vanderpol oscillator) using Simulink 

Author Name: C. Muni Saraswathi, Anu Radha B, K. Babulu 

Synopsis: 

The Heart Is The Center Of The Cardiovascular System. Whereas, The Term Cardio Refers To The Heart, The Term Vascular Refers To Blood Vessels. The Heart Acts As A Pump, And Maintains A Constant Circulation Of Blood Throughout The Body. As Blood Flows Through Body Tissues, Nutrients And Oxygen Move From The Blood In To Interstitial Fluid And Then Into Cells. At The Same Time The Blood Picks Up Wastes, Carbondioxide, And Heat. Even At Rest, Our Heart Pumps 30 Times Its Own Weight Each Minute, About 5 Liters To The Lungs And The Same Volume To The Rest Of The Body. The Physiological Oscillators Produce Oscillations, In The Form Of Stable, Closed Trajectory Called A Limit Cycle. These Oscillations Exhibit The Phenomenon Of Frequency Entrainment Or Phase Locking. These Are Analyzed By Presenting Vanderpol Oscillator. Vanderpol Oscillator Is A Non-Linear Oscillator. In The Non-Limit Cycle Oscillator, External Disturbance Move The Phase Trajectory To Different Orbit Around The Centre And Will Not Come To Original  Point, Where As In Limit Cycle Oscillator, The Phase Trajectory Returns To Its Original Location. When Vander Pol Oscillator Is Driven By The External Frequency, Which Is Different With Natural Frequency Of The Oscillator, Then The Resultant Output Is Mixture Of Components That Result From The Interaction Of The Driving Periodicity On Natural Oscillations. If The External Frequency Is Equal To Natural Frequency Of Vendor Pol Oscillator, Then Nonlinear System Will Adopt The External Frequency. The Time Courses Of Oscillatory Activity Of Heart And Phase Trajectories Are Generated By Vanderpol Model By Using The Simulink. The Response Of Vander Pol Oscillator For Various External Frequencies Is Also Obtained.