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Design study of a miniaturized multi-layered antenna-inpackage for 2.4 GHZ wireless communication
No full textThis paper proposes a novel miniaturization technique to enhance the radiation properties of small multi-layer patch antenna used in packaged circuits. The multilayered antenna design is composed of three layers with different shapes. An enhancement on the radiation properties has been obtained by optimizing the geometry of the radiated element and the parasitic conductor of the middle layer. The whole design has been implemented on the FR4 substrate with dielectric constant of 4.4, thickness of 1.6 mm and Copper thickness of 5 m. The first layer is a driven element while second and the third layer are parasitic patch elements. The optimized multilayer antenna has a very small size of . Considering the small size of the antenna, a detailed study of the parameter affecting the radiation has been considered to force the antenna to operate at 2.4 GHz band. Miniaturization Techniques based on the current distribution have been also taken into account to shift down the resonant frequency and reduces more and more the antenna size at the designed operating frequency. The miniaturized antenna maintains performant radiation characteristics in terms of reflexion coefficient, bandwidth and directivity. All developed antennas are simulated using the commercial Electromagnetic CST Microwave Studio software. Achieved results demonstrate a good performance with low cost and compact size
Emotion Recognition from Facial Expression Based on Fiducial Points Detection and using Neural Network
No full textThe importance of emotion recognition lies in the role that emotions play in our everyday lives. Emotions have a strong relationship with our behavior. Thence, automatic emotion recognition, is to equip the machine of this human ability to analyze, and to understand the human emotional state, in order to anticipate his intentions from facial expression. In this paper, a new approach is proposed to enhance accuracy of emotion recognition from facial expression, which is based on input features deducted only from fiducial points. The proposed approach consists firstly on extracting 1176 dynamic features from image sequences that represent the proportions of euclidean distances between facial fiducial points in the first frame, and faicial fiducial points in the last frame. Secondly, a feature selection method is used to select only the most relevant features from them. Finally, the selected features are presented to a Neural Network (NN) classifier to classify facial expression input into emotion. The proposed approach has achieved an emotion recognition accuracy of 99% on the CK+ database, 84.7% on the Oulu-CASIA VIS database, and 93.8% on the JAFFE database
Design of 10 to 12 GHz Low Noise Amplifier for Ultra-wideband (UWB) System
No full textBalanced amplifier is the structure proposed in this article, it provides better performance. In fact, the single amplifier meets the specification for noise figure and gain but fails to meet the return loss specification due to the large mis-matches on the input & outputs. To overcome this problem one solution is to use balanced amplifier topography. In this paper, a wide-band and high-gain microwave balanced amplifier constituted with branch line coupler circuit is proposed. The amplifier is unconditionally stable in the band [9-13] GHz where the gain is about 20dB. The input reflection (S11) and output return loss (S22) at 11 GHz are -33.4dB and -33.5dB respectively.
Pulse Density Modulation Based Series Resonant Inverter Fed Induction Heater System
No full textThis paper deals with implementation of a multi-output Series Resonant Inverter(SRI) for induction heating applications, which uses pulse density modulation(PDM) control for full bridge Series resonant inverters for output voltage and power control. It ensures better efficiency performances than conventional control strategies. The proposed converter can be considered as a two output extension of a full bridge inverter. This full bridge inverter can control the two outputs, simultaneously and independently, up to their rated powers, which reduces the usage of number of components as compared with conventional method. It also ensures higher utilization of switches used for its operation. A two output full bridge series resonant inverter is simulated and implemented. The Experimental results are compared with the simulation results
Experimental study and modeling of three grid-connected photovoltaic technologies of Meknes City
No full textPhotovoltaic (PV) systems are the most promising renewable energy source in Morocco due to its abundant solar irradiation. The Moroccan government has launched various renewable energy programs to encourage the use of PV systems. In this work we present a comparative study in terms of energy produced and the efficiency of a grid connected photovoltaic (PV) system installed on the roof of the building occupied by the “Ecole Supérieure de Technologie de Meknes” (ESTM). The on-grid connected photovoltaic system has a total power of 5860 Watts (Wp). This system provides an average daily reduction of 30 kWh in the consumption of electrical energy at ESTM facilities; this will allow us to save fossil fuels and reduce emissions of greenhouse gas. The average annual production of electric power is estimated at 10.5 MWh, equivalent to burning 0.9 tons of oil, which will prevent the emission of about 2 tons / year of CO2 in the atmosphere. Three different commercial solar modules, manufactured with different materials and technologies in monocrystalline silicon, polycrystalline silicon and amorphous silicon were tested
A Commercial Low Cost, Highly Efficient UC3842 based High Brightness LED (HBLED) Lamp
No full textThe conventional lighting sources like incandescent and fluorescent lamps are replaced by High Brightness Light Emitting Diodes (HB-LEDs). In this paper, a HBLED driver using a Single Ended Primary Inductor Converter (SEPIC) with input Power Factor Correction (PFC) is presented. PFC is accomplished using a commercial inexpensive Peak Current Mode Controller (PCMC) IC UC3842 is newly combined with SEPIC converter. Extensive simulation results are carried out and a laboratory prototype to power 18W LED array from AC mains is implemented and the results are presented in detail.
Finite-Control-Set Predictive Current Control Based Real and Reactive Power Control of Grid-Connected Hybrid Modular Multilevel Converter
No full textThis paper proposes the grid application of modified three-phase topology of Modular Multilevel Converter (MMC) using finite-control-set predictive control. This topology has reduced number of switch counts compared to the conventional MMC, eliminates the problem of circulating current and having higher efficiency. A single dc source is required to produce sinusoidal outputs. The number of sub-modules (SMs) in this topology is half of the SMs required in case of MMC, in addition to a single H-bride circuit per phase. The finite-control-set predictive current control scheme for the grid connected dc source through the Hybrid Modular Multilevel Converter (HMMC). This controller controls the desired real and reactive power demand of the grid instantaneously. The simulation study of a three phase grid connected system has been done in Matlab/Simulink and the results are provided for the different real and reactive power demands, to validate the concepts
Enhanced Three-Phase Inverter Faults Detection And Diagnosis Approach - Design And Experimental Evaluation
No full textEfficiency, reliability, high power quality and continuous operation are important aspects in electric vehicle attraction system. Therefore, quick fault detection, isolation and enhanced fault-tolerant control for open-switches faults in inverter driving systems become more and more required in this filed. However, fault detection and localization algorithms have been known to have many performance limitations due to speed variations such as wrong decision making of fault occurrence. Those weaknesses are investigated and solved in this paper using currents magnitudes fault indices, current direct component fault indices and a decision system. A simulation model and experimental setup are utilized to validate the proposed concept. Many simulation and experimental results are carried out to show the effectiveness of the proposed fault detection approach
Simulation of AC-DC Converter for High Power Application
No full textThis manuscript deals with the simulation of AC - DC Zeta converter for high power drive application with greater efficiency, lesser losses and power factor correction. It involves simpler control circuitry with less external components. The explanation of Fundamental function of Zeta converter is given in this paper. To condense the harmonic content the PI, PID and Fuzzy Logic controller are used. The operation of Zeta converter in open loop, closed loop is obtained. Closed loop system of zeta converter proves better performance over open loop system. Open and closed loop circuits are simulated by using MATLAB simulink. By giving disturbance in closed loop and open loop systems, feat of Zeta converter is compared.
A New Photovoltaic Blocks Mutualization System For Micro-Grids Using An Arduino Board And Labview
No full textThe photovoltaic systems are often employed into micro-grids; Micro-grids are small power grids designed to provide a reliable and better power supply to a small number of consumers using renewable energy sources.This paper deals with DC micro-grids and present a new system of monitoring and sharing electricity between homes equipped with photovoltaic panels (PV) in the goal to reduce the electrical energy waste. The system is based on dynamic sharing of photovoltaic blocks through homes in stand-alone areas, using an arduino board for controlling the switching matrix. The LABVIEW program is used to further process and display collected data from the system in the PC screen. A small-scale prototype has been developed in a laboratory to proof the concept. This prototype demonstrates the feasibility and functionality of the system