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FPGA Based Selective Harmonic Elimination Technique for Multilevel Inverter
No full textHarmonic elimination at the fundamental frequency is very much appropriate for high and medium range of power generation and applications. This paper considers a new technique for selective harmonic elimination (SHE), in which the total harmonic distortion (THD) is minimized when compared with that of the conventional one. With this technique, the harmonics at lower order are eliminated, which are more predominant than the higher ones.Cascaded H-Bridge inverter fed by a single DC is considered which is simulated with the switching angles generated by both the conventional method of SHE and the new method of SHE. The simulated results of the load voltage and the waveforms of the harmonic analysis are shown. The THD values are compared for the two techniques. The experimental results are also shown for the new technique. The switching angles are generated with the help of field programmable gated array (FPGA) in the hardware. The value of experimental THD of voltage is compared with that of simulated THD and the comparison prove that the results are satisfactory
Classification of Atrial Arrhythmias using Neural Networks
No full textElectrocardiogram (ECG) is an important tool used by clinicians for successful diagnosis and detection of Arrhythmias, like Atrial Fibrillation (AF) and Atrial Flutter (AFL). In this manuscript, an efficient technique of classifying atrial arrhythmias from Normal Sinus Rhythm (NSR) has been presented. Autoregressive Modelling has been used to capture the features of the ECG signal, which are then fed as inputs to the neural network for classification. The standard database available at Physionet Bank repository has been used for training, validation and testing of the model. Exhaustive experimental study has been carried out by extracting ECG samples of duration of 5 seconds, 10 seconds and 20 seconds. It provides an accuracy of 99% and 94.3% on training and test set respectively for 5 sec recordings. In 10 sec and 20 sec samples it shows 100% accuracy. Thus, the proposed method can be used to detect the arrhythmias in a small duration recordings with a fairly high accuracy
Simulation and Real Time Implementation of Various PWM Strategies for 3 Φ Multilevel Inverter Using FPGA
No full textFor high power applications Multilevel Inverter (MLI) is extensively used. The major advantages of MLI are good power quality, low switching losses and maintenance of the desired voltage. In this work, the three phase cascaded multi level inverter is analyzed under various modulation techniques that include Sub-Harmonic Pulse Width Modulation (SHPWM) i.e. Phase Disposition (PD) strategy, Phase Opposition Disposition (POD) strategy, Alternate Phase Opposition Disposition (APOD) strategy, hybrid strategy (PD and PS) and Phase Shift (PS) strategy. The study will help to choose those techniques with reduced harmonics for the chosen three phase cascaded MLI with R-L load. The Total Harmonic Distortion (THD), VRMS (fundamental), crest factor and form factor are evaluated for various modulation indices at two different switching frequencies (3.15KHz and 6 KHz). Simulation is performed using MATLAB-SIMULINK. It is observed that HYBRID PWM and PSPWM methods provide output with relatively low distortion for low and high switching frequencies. PODPWM and PSPWM are found to perform better since they provide relatively higher fundamental RMS output voltage for 6 KHz and 3.15 KHz switching frequencies. The experimental result shows PSPWM provide output with low distortion and HYBRID PWM provide output with higher fundamental RMS voltage for fc=3.15KHz. The experimental results were obtained only for fc=3.15KHz
FPGA implementation of DS-CDMA Transmitter and Receiver
No full textDirect sequence spread Spectrum (DSSS) is also known as direct sequence code division multiplexing. In direct sequence spread spectrum the stream of information to be transmitted is divided into small pieces each of which is allocated across to a frequency channel across the spectrum. Data signal at the point of transmission is collaborated with a higher data-rate bit sequence (also called chipping code) that divides the data according to a spreading ratio. A redundant chipping code helps the signal resist interference and also enables the original data to be recovered if data bits are damaged during the transmitting. In this project direct sequence spread spectrum principle based code division multiple access (CDMA) transmitter and receiver is implemented on SPARTAN 3E FPGA. The Xilinx synthesis technology (XST) of Xilinx ISE tool used for synthesis of transmitter and receiver on FPGA Spartan 3E
Application of Inverse Perspective Mapping for Advanced Driver Assistance Systems in Automotive Embedded Systems
No full textIn the recent times vehicle manufactures and automotive suppliers are progressing towards building vision based subsystems for provisioning driver assistance while targeting the automotive safety critical needs. While the acquired images constitute the fundamental input for any vision based system, transforms on images become essential to derive and gain insight into certain specific features. These derived features are used and reused at multiple places for varied automotive applications. This situation warrants a scalable and flexible image processing platform for a class of automotive applications. An attempt is made in this Research work to propose architecture that, specially, includes a layer of image transformations and to implement a prototype image processing platform. Inverse Perspective Mapping (IPM), a widely used class of transforms is emphasized in the present architecture alongside other nominal transforms. Lane departure warning system is implemented on this platform for the purpose of illustration and to analyze the effectiveness of the proposed architectur
Hybrid System Power Generation'wind-photovoltaic' connected to the Electrical Network 220 kV
No full textRenewable energy have the potential to generate electricity cleanly without pollution and a lesser dependence of resources for this production of electric power by these systems sources such as solar, wind, hydro, geothermal and biomass instead anti-environmental conventional systems such as gas, coal and oil is a remarkable idea but not frequent in Algeria. Our research focuses on the study of a hybrid energy system (Photovoltaic-Wind), connected to the Electrical Network 220 kV and this by tracking the maximum power point (MPPT) for two energy sources. For this, methods based on optimization algorithms were used side PV array and Wind turbine. With regard to the wind turbine, optimization was based on an analytical approach method. The Matlab/Simulink is used for simulated power output from Hybrid System, power delivered to or from grid and phase voltage of the inverter le
A Self-Tuned Simulated Annealing Algorithm Using Hidden Markov Model
No full textSimulated Annealing algorithm (SA) is a well-known probabilistic heuristic. It mimics the annealing process in metallurgy to approximate the global minimum of an optimization problem. The SA has many parameters which need to be tuned manually when applied to a specific problem. The tuning may be difficult and time-consuming. This paper aims to overcome this difficulty by using a self-tuning approach based on a machine learning algorithm called Hidden Markov Model (HMM). The main idea is allowing the SA to adapt his own cooling law at each iteration, according to the search history. An experiment was performed on many benchmark functions to show the efficiency of this approach compared to the classical one
Application of the ELECTRE III Method at the Moroccan Rural Electrification Program
No full textAs part of the integrated strategy of the Moroccan state aimed at the social and economic development of the Moroccan rural community, an electrification program has been in place since the 90s. This program, called PEGR, has for main objective the improvement of the electrification rate for the national rural world. Given the large number of villages to be electrified and the colossal budget that will induce, several criteria have been retained to objectively distinguish the villages with the highest priority for electrification. Given the nature of this problem to be solved, which is a multicriteria decision aid problem, we propose in this article to use the multicriteria aggregation method ELECTRE III to rank the villages from the highest priority to the lowest priority for the electrification
A Comparative Analysis on the Evaluation of Classification Algorithms in the Prediction of Diabetes
No full textData mining techniques are applied in many applications as a standard procedure for analyzing the large volume of available data, extracting useful information and knowledge to support the major decision-making processes. Diabetes mellitus is a continuing, general, deadly syndrome occurring all around the world. It is characterized by hyperglycemia occurring due to abnormalities in insulin secretion which would in turn result in irregular rise of glucose level. In recent years, the impact of Diabetes mellitus has increased to a great extent especially in developing countries like India. This is mainly due to the irregularities in the food habits and life style. Thus, early diagnosis and classification of this deadly disease has become an active area of research in the last decade. Numerous clustering and classifications techniques are available in the literature to visualize temporal data to identify trends for controlling diabetes mellitus. This work presents an experimental study of several algorithms which classifies Diabetes Mellitus data effectively. The existing algorithms are analyzed thoroughly to identify their advantages and limitations. The performance assessment of the existing algorithms is carried out to determine the best approach
Dietary Nutrient Intake and Obesity Prevalence among Native American Adolescents
No full textThe prevalence of obesity among adolescent minority populations has been long recognized, but little research has been done on Native Americans adolescents. Using anthropometric measurements and dietary assessments, the findings within each study have shown to obtain baseline measures to determine the prevalence of obesity within the Sherman Indian High School’s Native American adolescent population. Data of each assessment appear to be of use for predicting obesity and creating effective future interventions. Compiling data using the Harvard School of Public Health Youth/Adolescent Questionnaire (HSPH YAQ), a semi-quantitative food frequency questionnaire allowed significant data to be found between normal and obese weight students. Utilizing each finding allows more effective ways of targeting and reversing the inclining rate of obesity among Native American adolescents. Results show that antioxidants being examined on such as vitamin E and lycopene are beneficial in lowering the obesity rate among Native American adolescents. Levels of fiber, thiamin and folate consumption was significantly lower among the obese population in Sherman Indian High School’s Native American adolescents. Moreover, dietary mineral intake was shown to be lower among obese Native American adolescents comparing with the normal weight group. The results suggested that dietary consumption of these nutrients might correlate and predict obesity and lead to the development of effective interventions for Native Americans. This study also found the effects of total fiber and vitamin B in diets with lifestyle intervention in prediabetic adults, showing that total fiber intake among the normal weight students is significantly higher than obese students, indicating that fiber and vitamin profile could be important determinants of the effect of dietary intervention