Support Vector Regression Based S-transform for Prediction of Single and Multiple Power Quality Disturbances

This paper presents a novel approach using Support Vector Regression (SVR) based S-transform to predict the classes of single and multiple power quality disturbances in a three-phase industrial power system. Most of the power quality disturbances recorded in an industrial power system are non-stationary and comprise of multiple power quality disturbances that coexist together for only a short duration in time due to the contribution of the network impedances and types of customers’ connected loads. The ability to detect and predict all the types of power quality disturbances encrypted in a voltage signal is vital in the analyses on the causes of the power quality disturbances and in the identification of incipient fault in the networks. In this paper, the performances of two types of SVR based S-transform, the non-linear radial basis function (RBF) SVR based S-transform and the multilayer perceptron (MLP) SVR based S-transform, were compared for their abilities in making prediction for the classes of single and multiple power quality disturbances. The results for the analyses of 651 numbers of single and multiple voltage disturbances gave prediction accuracies of 86.1% (MLP SVR) and 93.9% (RBF SVR) respectively. Keywords: Power Quality, Power Quality Prediction, S-transform, SVM, SV

Existence results for impulsive fractional differential equations with pp-Laplacian via variational methods

summary:This paper presents several sufficient conditions for the existence of at least one classical solution to impulsive fractional differential equations with a $p$-Laplacian and Dirichlet boundary conditions. Our technical approach is based on variational methods. Some recent results are extended and improved. Moreover, a concrete example of an application is presented

Infinitely many solutions for impulsive nonlinear fractional boundary value problems

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Differential-Algebraic Equations and Beyond: From Smooth to Nonsmooth Constrained Dynamical Systems

The present article presents a summarizing view at differential-algebraic equations (DAEs) and analyzes how new application fields and corresponding mathematical models lead to innovations both in theory and in numerical analysis for this problem class. Recent numerical methods for nonsmooth dynamical systems subject to unilateral contact and friction illustrate the topicality of this development.Comment: Preprint of Book Chapte

Existence of three solutions for impulsive nonlinear fractional boundary value problems

In this work we present new criteria on the existence of three solutions for a class of impulsive nonlinear fractional boundary-value problems depending on two parameters. We use variational methods for smooth functionals defined on reflexive Banach spaces in order to achieve our results

Optimization techniques for satellites proximity maneuvers

The main topic of this dissertation is the control optimization problem for satellites Rendezvous and Docking. Saving resources is almost as important as the mission safeness and effectiveness. Three different numerical approaches are developed. The first two techniques deal with realtime and sub-optimal control, generating a reliable control sequence for a chaser spacecraft which eventually docks to a target. The first approach uses dynamic programming to quickly generate a sub-optimal control sequence on a predetermined path to be followed by one of the two vehicles involved into the docking operations. The second method presents a fast direct optimization technique, which was previously validated on real aircraft for trajectory optimization. The third approach aims to take into account the limitations of space qualified hardware, in particular thrusters. The new technique fuses the use of a set of low thrust on-off engines with impulsive-high-thrust engines. The hybrid method here developed combines and customizes different techniques. The relative motion in the above mentioned control strategies is represented by a linear dynamic model. As secondary topic of this dissertation, the use of a genetic algorithm optimizer to find possible conditions under which spacecraft relative motion can be periodic, or at least bounded, is presented. This analysis takes into account the J2 gravity perturbation and some drag effects. The importance of the obtained results directly apply to the problem of formation keeping, as natural dynamics can be exploited to reduce the amount of active control preventing the spacecrafts to drift apart along tim