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Search Results: 1 - 10 of 1632 matches for " Mostafa Baghouri "
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Ameliorate Threshold Distributed Energy Efficient Clustering Algorithm for Heterogeneous Wireless Sensor Networks
Mostafa Baghouri,Saad Chakkor,Abderrahmane Hajraoui
Computer Science , 2014, DOI: 10.14569/IJACSA.2014.050413
Abstract: Ameliorating the lifetime in heterogeneous wireless sensor network is an important task because the sensor nodes are limited in the resource energy. The best way to improve a WSN lifetime is the clustering based algorithms in which each cluster is managed by a leader called Cluster Head. Each other node must communicate with this CH to send the data sensing. The nearest base station nodes must also send their data to their leaders, this causes a loss of energy. In this paper, we propose a new approach to ameliorate a threshold distributed energy efficient clustering protocol for heterogeneous wireless sensor networks by excluding closest nodes to the base station in the clustering process. We show by simulation in MATLAB that the proposed approach increases obviously the number of the received packet messages and prolongs the lifetime of the network compared to TDEEC protocol.
Performance Analysis of Faults Detection in Wind Turbine Generator Based on High-Resolution Frequency Estimation Methods
Saad Chakkor,Mostafa Baghouri,Abderrahmane Hajraoui
Computer Science , 2014, DOI: 10.14569/IJACSA.2014.050420
Abstract: Electrical energy production based on wind power has become the most popular renewable resources in the recent years because it gets reliable clean energy with minimum cost. The major challenge for wind turbines is the electrical and the mechanical failures which can occur at any time causing prospective breakdowns and damages and therefore it leads to machine downtimes and to energy production loss. To circumvent this problem, several tools and techniques have been developed and used to enhance fault detection and diagnosis to be found in the stator current signature for wind turbines generators. Among these methods, parametric or super-resolution frequency estimation methods, which provides typical spectrum estimation, can be useful for this purpose. Facing on the plurality of these algorithms, a comparative performance analysis is made to evaluate robustness based on different metrics: accuracy, dispersion, computation cost, perturbations and faults severity. Finally, simulation results in MATLAB with most occurring faults indicate that ESPRIT and R-MUSIC algorithms have high capability of correctly identifying the frequencies of fault characteristic components, a performance ranking had been carried out to demonstrate the efficiency of the studied methods in faults detecting.
Efficiency Evaluation Metrics for Wireless Intelligent Sensors Applications
Saad Chakkor,El Ahmadi Cheikh,Mostafa Baghouri,Abderrahmane Hajraoui
Computer Science , 2014, DOI: 10.5815/ijisa.2014.10.01
Abstract: The metrology field has been progressed with the appearance of the wireless intelligent sensor systems providing more capabilities such as signal processing, remote multi-sensing fusion etc. This kind of devices is rapidly making their way into medical and industrial monitoring, collision avoidance, traffic control, automotive and others applications. However, numerous design challenges for wireless intelligent sensors systems are imposed to overcome the physical limitations in data traffic, such as system noise, real time communication, signal attenuation, response dynamics, power consumption, and effective conversion rates etc, especially for applications requiring specific performances. This paper analyzes the performance metrics of the mentioned sensing devices systems which stands for superior measurement, more accuracy and reliability. Study findings prescribe researchers, developers/ engineers and users to realizing an optimal sensing motes design strategy that offers operational advantages which can offer cost-effective solutions for an application.
Comparative Performance Analysis of Wireless Communication Protocols for Intelligent Sensors and Their Applications
Saad Chakkor,El Ahmadi Cheikh,Mostafa Baghouri,Abderrahmane Hajraoui
Computer Science , 2014, DOI: 10.14569/IJACSA.2014.050413
Abstract: The systems based on intelligent sensors are currently expanding, due to theirs functions and theirs performances of intelligence: transmitting and receiving data in real-time, computation and processing algorithms, metrology remote, diagnostics, automation and storage measurements...The radio frequency wireless communication with its multitude offers a better solution for data traffic in this kind of systems. The mains objectives of this paper is to present a solution of the problem related to the selection criteria of a better wireless communication technology face up to the constraints imposed by the intended application and the evaluation of its key features. The comparison between the different wireless technologies (Wi-Fi, Wi-Max, UWB, Bluetooth, ZigBee, ZigBeeIP, GSM/GPRS) focuses on their performance which depends on the areas of utilization. Furthermore, it shows the limits of their characteristics. Study findings can be used by the developers/ engineers to deduce the optimal mode to integrate and to operate a system that guarantees quality of communication, minimizing energy consumption, reducing the implementation cost and avoiding time constraints.
Use of an Energy-Like Integral to Study the Motion of an Axi-Symmetric Satellite under Drag and Radiation Pressure  [PDF]
Ahmed Mostafa
International Journal of Astronomy and Astrophysics (IJAA) , 2015, DOI: 10.4236/ijaa.2015.53019
Abstract: The axi-symmetric satellite problem including radiation pressure and drag is treated. The equations of motion of the satellite are derived. An energy-like is given for a general drag force function of the polar angle θ, and then it is used to find a relation for the orbit equation of the satellite with initial conditions satisfying the vanishing of arbitrarily choosing higher derivatives of the velocity.
The Predictive Value of Biopsy of the Pancreas and Its Therapeutic Impact in Autoimmune Diabetes  [PDF]
Wael Nassar, Mostafa A. Mostafa
Journal of Diabetes Mellitus (JDM) , 2014, DOI: 10.4236/jdm.2014.44041
Abstract: Diabetes Mellitus is by definition an end-stage organ failure. Type 1 diabetes mellitus (T1DM) is an autoimmune disease. Auto-inflammatory infiltrate appears to characterize the insulitis associated with T2DM. Recently, in 2013, Eva Corpos and colleagues described a comprehensive composition of peri-islet capsules and their basement membrane (BM). Virtanen I, Otonkoski T and Irving-Rodgers H.F. have reported similar descriptions few years earlier which have not been taken seriously as they deserve. Bluestone JA, Virtanen I and Irving-Rodgers H.F. and other colleagues reported that accumulation of the lymphocytes around the islets without invasion of the BM is the first step in disease induction (non-destructive insulitis phase). Invasion of the BM byleucocytic infiltration (destructive insulitis phase) occurs over a period of several years offering a good window for therapeutic intervention. Clinical symptoms appear only when 70% - 90% of β-cell mass are destroyed. This data emphasize the importance of identification and classification of such pathologic features by performing a biopsy of the pancreas with histoimmunochemistry analysis at the pre-hyperglycemic stage in a high risk genetically predisposed autoimmune suspected patient which may at least in part help to achieve new therapeutic approaches and help in halting the progression to end stage pancreatic disease (ESPD) known as diabetes mellitus. In this review we are going to emphasize the predictive role biopsy of the pancreas can build up a solid gold standard tool in diagnosis, stage and therapeutically follow up autoimmune diabetes mellitus.
Arterial Pulse Pressure Variation versus Central Venous Pressure as a Predictor for Fluid Responsiveness during Open Major Abdominal Operations  [PDF]
Mostafa M. Hussein, Raham H. Mostafa
Open Journal of Anesthesiology (OJAnes) , 2018, DOI: 10.4236/ojanes.2018.82005
Abstract: Introduction: Fluid resuscitation is the cornerstone in the management of hemodynamically unstable patients. Dynamic parameters of fluid responsiveness, like pulse pressure variation, have the advantage of being more reliable index for fluid management. Objective: The aim of our study was to compare between arterial pulse pressure variation (PPV) versus central venous pressure (CVP) as a predictor for fluid responsiveness during major open abdominal operations. Patients and Methods: 60 adult patients under general anesthesia with mechanical ventilation underwent open major abdominal surgical procedures were included in our prospective randomized controlled study. Intravenous fluid was infused and monitored by CVP in control group or by PPV in the other group. Hemodynamic variables (heart rate, invasive blood pressure, PPV and CVP) were measured at baseline after anesthesia induction and every 10 min, during first hour of operation, and then every 15 min, till end of surgery. Blood loss and total i.v. fluid & blood transfusion given to patients were recorded and compared between two groups intraoperatively. Results: Patients in the PPV group required more intraoperative fluid and blood transfusion than patients in CVP group to achieve more stable hemodynamic parameters. The fall in blood pressure (>20% of baseline) and increase in heart rate are more common in CVP group (p < 0.05). Conclusion: PPV is a better predictor and a good guide for fluid responsiveness. More stable hemodynamic variables are observed in PPV group.
Genetic Algorithm Based Performance Analysis of Self Excited Induction Generator  [PDF]
Hassan Ibrahim, Mostafa Metwaly
Engineering (ENG) , 2011, DOI: 10.4236/eng.2011.38105
Abstract: This paper investigates the effects of various parameters on the terminal voltage and frequency of self excited induction generator using genetic algorithm. The parameters considered are speed, capacitance, leakage reactance, stator and rotor resistances. Simulated results obtained using genetic algorithm facilitates in exploring the performance of self-excited induction generator. The paper henceforth establishes the application of user friendly genetic algorithm for studying the behaviour of self-excited induction.
Effect of Local and Global Scour on Lateral Response of Single Piles in Different Soil Conditions  [PDF]
Yasser E. Mostafa
Engineering (ENG) , 2012, DOI: 10.4236/eng.2012.46039
Abstract: Marine structures, offshore platforms and bridge piers are usually supported on foundation piles. These piles are subjected to lateral loading due to wind, waves and currents. Piles installed in marine or river environments are susceptible to scour depending on wave and current characteristics and soil types. In this paper, the effect of local and global scour on behavior of laterally loaded piles installed in different soil conditions has been investigated. Finite element model (FEM) using the software program PLAXIS and Winkler model using the software program LPILE were used in the analyses. Different parameters were investigated such as soil types, scour depth, scour hole dimension, pile material, submerged condition, magnitude of lateral load and load eccentricity. The results showed that scour has a significant impact on piles installed in sand and a less significant impact on piles installed in clay. Global scour has a significant impact on pile lateral displacement and bending stresses. The effect of scour is more significant if piles are subjected to large lateral loads due to the nonlinear response of pile-soil system. Effect of scour of stiff clayey soils on piles is more pronounced than that of soft clayey soils.
Design Considerations for Pile Groups Supporting Marine Structures with Respect to Scour  [PDF]
Yasser E. Mostafa
Engineering (ENG) , 2012, DOI: 10.4236/eng.2012.412106
Abstract: Piles supporting marine structures such as jetties, relieving platforms, quay walls and fixed offshore structures are subjected to lateral loads due to berthing and mooring forces, wind, waves, storm surges and current forces. This paper presents some factors that affect the design of pile groups supporting marine structures founded in cohesionless soils. Some main aspects that should be considered in the pile group design are addressed such as pile batter angle, pile group arrangement, pile spacing, pile slenderness ratio and magnitude of lateral static loading. Numerical analyses were conducted to investigate these design aspects with and without impact of scour. Different scour depths were considered to cover the possible root causes of scour around pile groups such as waves, current and ship propeller jets. The study revealed that scour has greater impact on lateral loading of pile groups compared to its impact on single piles. Pile groups with side-by-side arrangement exposed to scour are more critical than single piles and piles groups with tandem arrangement due to the combined effect of scour and pile-soil-pile interaction. It is also concluded that scour protection is not always required. More attention and considerations should be given to scour protection around piles especially if the piles are closely spaced, arranged side-by-side and if slenderness ratio is less than 12.5.
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