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In this paper, the main idea of the proposed method is to build a secure image transmission combining watermarking and encryption techniques. From one hand, it consists of an image embedded in another one using a Discrete Wavelet Transform (DWT) to guarantee the process of watermarking. Then, the resultant watermarked image is encrypted using the master 4D discrete-time hyperchaotic Henon maps. From...
This paper deals with a maintenance optimization problem for a second hand system. The system is purchased from a second hand market, upgraded and then moved to operate under a more severe operating environment than the initial one. The system degrades stochastically and its degradation process is impacted by the operating environment where it evolves. The present paper investigates the relationship...
The static response of microelectronic capacitive pressure sensors with a fine silicon rectangular membrane or square membrane is studied in the low distortion limit. The response represented by the variation of the capacity with the pressure, presents two parts: a nearly linear part corresponding to values of PN lower than 0,6 (unity) and second highly non linear part for PN higher than 0,6(unity)...
This paper deals with the problem of designing a new iterative learning control (ILC) for a class of strict-feedback nonlinear systems subject to both structured and unstructured uncertainties and dynamic disturbances. These systems are assumed to perform the same task repeatedly under alignment condition. Simple learning mechanisms are proposed to approximate the unknown nonlinear state-dependent...
This paper offers an improved Tip speed ratio (TSR) technique for variable speed operating mode of grid connected doubly-fed induction generator (DFIG) system. As we know from the literature, the TSR is the fastest MPPT (maximum power point tracking) technique because it uses directly the wind velocity signal to compute the optimal rotational speed of the wind turbine, However, the significant wind...
This paper presents an improvement algorithm of Model Predictive Control (MPC) for the quasi Z-Source Inverter (qZSI) with a standalone system. The improved algorithm decreases number of the desired sensors from five into three, where it just needs two current sensors for measuring the AC currents, and another voltage sensor for capacitor voltage detection. The inductor current will be estimated according...
This paper presents the optimization design and analysis of axial flux permanent-magnet (AFPM) machine (internal stator external rotor) used in flywheel energy storage system (FESS). The main idea of design is reduce the pressure and friction acting on the lower bearing system, thus reducing the bearing losses and, therefore, the self-discharge of the stored energy during the standby mode. Due to...
Different location determination methods using wireless signal strength have been proposed to improve the location accuracy and mitigate the multipath problem in indoor environment. In this paper, a fingerprinting-probabilistic approach for indoor localization using wireless technology is proposed. The method is based on the use of the Gaussian Mixture Model (GMM) to approximate the probability distribution...
A simple method based on that described in the international standard NE ISO 5167 is implemented to determine the mass flow rate and other parameters. The control procedures of calculation used for every measurement instrument will be developed according to the conditions of working and material available on site.
The students' portal represents a major part among university information systems. Lack of components distribution is a gap that leads to many problems in students' portals in most of universities worldwide, which is due to tightly-coupled components in the current portal framework. This paper reviews the common features of the general portal structure. A comparison between the traditional students'...
This paper presents a new Structured H∞ Design Method of proportional-integral (PI) controllers for Grid Feeding Connected Voltage Source Converters, based on MATLAB tools for tuning linear control systems in the frequency domain. The study consists in elaborating optimization of an H∞ robust control strategy for a Voltage Source Inverter (VSI) connected to the grid through a LCL filter. The PI controller...
In this paper, a novel transmission scheme based on the discrete-time fractional-order chaotic system for private digital communications is proposed. The fractional-order Modified-Henon map is used. By adjusting the fractional-orders appropriately, it has been shown that the fractional-order Modified-Henon system possesses a chaotic behaviour. The exact synchronization based on the delayed observer...
This paper presents a comprehensive modeling of a three-phase cage induction machine used as a self-excited squirrel-cage induction generator (SEIG), and discusses the regulation of the voltage and frequency of a self-excited SEIG based on the action of the static synchronous Compensator (STATCOM). The STATCOM with the proposed controller consists of a three-phase voltage-sourced inverter and a DC...
Parabolic trough solar thermal power plant is considered as one of the most mature, successful, proven and attractive technologies to produce electricity. The aim of this present study is to compare parabolic trough solar power plant with integrated thermal storage and fossil fuel backup system using two different heat transfer fluid (HTF); synthetic oil and molten salt. The comparison in their design,...
We present in this paper facial skin motion localization in a video sequence. When a face is under motion, a set of muscles, lip shape, eyebrows… are involved. The changes in successive images have direct effects on facial motion. Our work proposes an approach to detect points and areas that undergoes significant movement on a face under motion. Our method requires only simple devices: a webcam and...
In this paper, a complete characterization of the continuous state observability is derived for serial multicellular converter based on hybrid systems approach. More precisely, a necessary and sufficient condition for the continuous state observability for a given switching signal is elaborated for n-cell converter. Concrete examples are reported to highlight the derived results.
Facial demographic classification is an attractive topic in computer vision. Attributes such as age and gender can be used in many real life application such as face recognition and internet safety for minors. In this paper, we present a novel approach for age estimation and gender classification under uncontrolled conditions following the standard protocols for fair comparaison. Our proposed approach...
This paper discusses the concept of simple sliding mode to resolve the problem of control of a three-level boost converter for fuel cell applications. Simple sliding mode involves simple sliding surfaces; they are a class of surfaces that reveals the dispersion of nonlinear stabilizing surfaces for a given nonlinear MIMO system. In the case of the three-level boost converter, simple surfaces have...
In this paper, a heuristic optimization approach based on Artificial Bee Colony (ABC) algorithm is applied to the extraction of the five electrical parameters of a photovoltaic (PV) module. The proposed approach has several interesting features such as no prior knowledge of the physical system and its convergence is not dependent on the initial conditions. The extracted parameters have been tested...
This paper proposes a sliding mode controller for air supply subsystem on a PEM Fuel Cell system in order to regulate and replenish the oxygen depleted from the Fuel Cell cathode during stack current demands. According to the stack current, a reference value of air flow was obtained with the steady-state analysis of oxygen excess ratio (OER). To ensure the system working in the reference value of...
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