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In this paper a new approach to the robust asymptotic output tracking of an inverted pendulum is presented. The inverted pendulum is described by a third order nonlinear system. The proposed approach is as follows: First, we determine a static state feedback control law which solves the linear exact model matching (LEMM) problem resulting in an inputoutput (i/o) linearized closed -loop system. Second, in case where there exists a parameter uncertainty in the inverted pendulum model, we design a robust output tracking controller for the perturbed i/o linearized closed -loop system. The LEMM problem is solved using a new LEMM technique. This technique reduces the problem of finding the control law to that of solving a system of first order partial differential equations. Based on these equations, the general analytical solution for the feedback control law is derived. The robust design consists in determining the input signal of the perturbed i/o linearized closedloop system as a function of the state vector based on the construction of an appropriate Lyapunov function. LINTRODUCTIONThe contribution of this paper is two fold: A new technique to the linear exact model matching LEMM problem is presented, which subsequently is applied to an inverted pendulum controlled by a DC motor. Next, using this technique, a new approach to the robust controller design for the asymptotic output tracking of the inverted pendulum is established.The LEMM problem is part of a more general problem, known in the literature as the linearization problem. The problem of linearization has great theoretical and practical importance. The linearization problem may be distinguished into two major problems:. This problem consists of determining a state transformation and a control law (static or dynamic) which, when applied to a nonlinear system, modify a part of the input-state representation of the nonlinear system to the input-state representation of a linear system. I/O linearization problem [6] -[lo]. " 5 sproblem consists of determining a control law which, when applied to a nonlinear system, results in a dosed-loop system with linear i/o description. The closed-loop system may either allowed to be an arbitrary linear system [6] -[lo] or to have the Same i/o description with a prespecified linear model [6]. This last case constitutes the LEMM problem. ?he results reported on the LEMM problem are limited to the case of dynamic state feedback, yielding nonminimal controllers [6]. In this paper we present a new technique for the solution of the LEMM problem for a class of nonlinear systems via static state feedback. This technique reduces the problem of finding the desired control law to that of solving a system of first order partial differential equations, called LEMM design equations [ll] and [12]. Based on the LEMM design equations, the neceSSary and sufficient conditions for the problem to have a solution are derived. Furthermore, solving the LEMM design equations, the general form of the desired control law is characterized. The main a...

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In 2014, the graphic memoir Aivali created by the prolific comics artist with the pen name Soloùp was published in Greece with great success. His book constitutes a mosaic of personal experiences relating mainly to the cities of Aivali, Chania and the island of Lesbos. More precisely, Soloùp’s sequential art recounts his own personal experiences and reminiscences from a day trip in Aivali sometime in the 2000s, the autobiographical memories of three Greek authors that refer to their lives in the same city before and during the Greco-Turkish war in Asia Minor and the story of a Turkish young man, a family member of the Turkish writer Ahmet Yorulmaz, who resided in Chania until his settlement in Aivali in 1923. The purpose of this article is to examine the way in which the spirit of community is revived, how the city of Aivali is socially reconstructed and finally, the manner in which community and space are connected with each other and also with social memory. The notions of community, space and social memory will be approached through the lens of classical sociology theories formulated by Ferdinand Tönnies, Emile Durkheim and Maurice Halbwachs.