In this paper, first we show that the analytical solutions obtained in  the literature for the new coupled Konno-Oono system can be immediately presented  via the Weierstrass elliptic function or Jacobi elliptic functions. Next, we present a  new general real dark-type of soliton and a complex bright-type of envelope soliton  to this system in terms of the solutions of the sine-Gordon and sinh-Gordon equations  involving an arbitrary function via two new different transformations.

The main idea of this study is to evaluate the estimation performance of extended and unscented Kalman filters (EKF and UKF). So, these latter are introduced to estimate the dynamic states of a similar model operating with identical covariance matrices in the same situation. The mean square error (MSE) criterion is used to quantify the estimation error between the actual and the estimated values. The simulation results obtained with Matlab/ Simulink software confirm the superiority and efficiency of UKF over EKF, especially when the system is highly non-linear under process and measurement noises, such is the case of the inverted double pendulum mounted on a cart (DIPC).

This paper proposes a new approach of multi-spectral image compression based on the combination of the particle swarm optimization (PSO) and the discrete wavelet transforms (DWT). In the first stage, the PSO is used to reduce the redundancies in the spectral domain. In fact, the PSO transforms a given multispectral image to optimize the energy in the first band. Despite to the complexity of this kind of approach, the transformed multispectral image is easily computed by multiplying a de-correlation matrix and the input multispectral image. The de-correlation matrix is estimated via a PSO evolution derived by a defined fitness function. In the second stage, the compressed data, related to the input multispectral image, is computed from the transformed multispectral image using an efficient 2D-DWT based algorithm. In addition to this compression approach, the original multispectral image can be recovered using a decompression algorithm. Experimental results show the validity of our proposed approach. These significant results are evaluated according to Peak signal-to-noise ratio (PSNR), compression ratio (CR) and bits per pixel (bpp) metrics.

The mast support for small vertical axis wind turbine is considered an important parameter during the design process of wind turbine structure. It has been receiving a great attention by researchers and academics. This study presents a numerical investigation on the static and buckling strength behaviors of whole wind turbine mast structure by means Finite Element Analysis (FEA) technique. The FEA simulations are performed in order to evaluate the reliability and the strength of the mast structure under the extreme wind conditions (IEC 61400-2 and Eurocode 1991-1-4 standards) and gravity loads. The simulation results show that the mast structure will not undergo structural failure because the maximum stress induced is less than the yield strength of the material and the maximum displacement is within material allowable deformation limit. In addition, the buckling strength of the structure meets requirement of design.

As a key wind turbine element, the blade is a determining factor for reliability and efficiency of the turbine system and a main source of complicated and critical loads. In this present investigation, the strength behavior of a small composite blade for H-type Darrieus wind turbine was studied. Firstly, three-dimensional (3D) modelling of the blade structure with NACA 0018 airfoil profile was established. Secondly, the Finite element analysis (FEA) technique was conducted to perform the strength analysis of the blade structure subjected to extreme climatic conditions by means SOLIDWORKS SIMULATION software. This analysis was performed to identify the resistance, stiffness and reliability of the composite blade structure. The results from FEA identify that the structure of the blade will not be subjected to structural failure during WT operation (0 ~ 19 m/s) according to maximum principal stress equivalent (von Mises) and maximum displacements.

L'article décrit la conception et la mise en œuvre en temps réel d'une commande non linéaire appliquée à un système de conversion de l'énergie éolienne (SCEE). La commande backstepping a été mise en œuvre pour améliorer les performances du système de conversion éolienne basé sur un générateur synchrone à aimants permanents (PMSG) connecté au réseau. Deux convertisseurs statiques assurent la connexion au réseau et sont contrôlés par la modulation de largeur d'impulsion (MLI). L'algorithme de contrôle proposé assure un contrôle de vitesse adéquat pour extraire la puissance maximale. Une description détaillée des lois de contrôle du backstepping basées sur la technique de stabilité de Lyapunov a été exposée. Les résultats obtenus par l'application de cette approche ont clairement répondu aux exigences de robustesse et de suivi des références même dans des conditions de vent fluctuants, et ont confirmé l'efficacité d'un tel contrôle dans les modes de fonctionnement statique et dynamique.

The turbine blades are subjected to high operating temperatures and high centrifugal tensile stress due to rotational speeds. The maximum temperature at the inlet of the turbine is currently limited by the resistance of the materials used for the blades. The present paper is focused on the thermo-mechanical behavior of the blade in composite materials with reinforced mast under two different types of loading. The material studied in this work is a composite material, the selected matrix is a technical ceramic which is alumina (aluminum oxide Al₂O₃) and the reinforcement is carried out by short fibers of high modulus carbon to optimize a percentage of 40% carbon and 60% of ceramics. The simulation was performed numerically by Ansys (Workbench 16.0) software. The comparative analysis was conducted to determine displacements, strains and Von Mises stress of composite material and then compared to other materials such as Titanium Alloy, Stainless Steel Alloy, and Aluminum 2024 Alloy. The results were compared in order to select the material with the best performance in terms of rigidity under thermo-mechanical stresses. While comparing these materials, it is found that composite material is better suited for high temperature applications. On evaluating the graphs drawn for, strains and displacements, the blade in composite materials reinforced with mast is considered as optimum.

Volunteer computing (VC) has become a relatively mature technique of distributed computing. It is based on exploiting the idle time of ordinary online machines with the consent of their owners. Target applications are generally scientific projects requiring a huge amount of computational resources. Existing VC platforms raise several challenges. This work attempts to bring solutions for two defeats. The first one is the involvement of volunteers; the decreasing of participants affects the global performances. To cope with this, a new social volunteer computing environment is proposed in order to involve more volunteers. The second addressed problem is the task scheduling, which aims to optimize the use of resources. The proposed algorithm generates for each resource's class, a number of tasks whose cost of execution reflects the momentary capacity of the resources. The new solutions are validated through a theory of number's project, called “Collatz Conjecture.”