Applying flat systems technique in attitude fault tolerant control of an under-actuated satellite has been investigated in this article. The main purpose of this study is development and implementation of a new idea in order to recovery of satellite stability and its acceptable performance in actuator fault scenarios. Solving the attitude fault tolerant control problem is based on consideration...

In this paper, we define a new projective invariant and call it W̃ -curvature. We prove that a Finsler manifold with dimension n ≥ 3 is of constant flag curvature if and only if its W̃ -curvature vanishes. Various kinds of projectively flatness of Finsler metrics and their equivalency on Riemannian metrics are also studied. M.S.C. 2010: 53B40, 53C60.

We introduce the concept of flatness degree for matroids, as a generalization of submodularity. This represents weaker variations of the concept of flatness which characterize strict gammoids for finite matroids. We prove that having flatness degree 3, which is the smallest non-trivial flatness degree, implies pseudomodularity on the lattice of flats of the matroid. We show however an example o...

in this paper, a new control method based on fel electro hydraulic servo control withnonlinear flux and internal friction, has been presented. the new approach based oncontrollers combined by a classic pd controller and a fuzzy controller is smart. this newtechnique has a good ability to control the performance and stability. simulations have beencarried out in matlab environment and the result...

The purpose of this paper is to illustrate the potential interest of the control theory framework for cryptographic applications. It is shown that under the properties of left invertibility and flatness, dynamical systems are structurally equivalent to some specific cryptographic primitives called self-synchronizing stream ciphers. After having motivated the interest of considering hybrid syste...

In this paper, we use computer vision as a feedback sensor in a control loop for landing an unmanned air vehicle (UAV) on a landing pad. The vision problem we address here is then a special case of the classic ego-motion estimation problem since all feature points lie on a planar surface (the landing pad). We study together the discrete and differential versions of the ego-motion estimation, in...

Valdis Laan in [5] introduced an extension of strong flatness which is called weak pullback flatness. In this paper we introduce a new property of acts over monoids, called U-WPF which is an extension of weak pullback flatness and give a classification of monoids by this property of their acts and also a classification of monoids when this property of acts implies others. We also show that regu...

this paper presents a new optimization algorithm to design an optimal proportional, integral, derivative (pid) controller in hydro-turbine generator governor for damping output frequency oscillations. in this research, we utilize a stochastic and optimal based pid controller to control frequency-response of the hydro turbine. the proposed algorithm is employed to design an optimal pid controlle...

This paper is devoted to the study of products of classes of right $S$-posets possessing one of the flatness properties and preservation of such properties under products. Specifically, we characterize a pomonoid $S$ over which its nonempty products as right $S$-posets satisfy some known flatness properties. Generalizing this results, we investigate products of right $S$-posets satisfying Condi...