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[Studies in Computational Intelligence 481] Artur Babiarz, Robert Bieda, Karol Jędrasiak, Aleksander Nawrat (auth.), Aleksander Nawrat, Zygmunt Kuś (eds.) - Vision Based Systemsfor UAV Applications (2013, Sprin

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312 A. Czornik, A. <strong>Nawrat</strong>, and M. Niezabitowski<br />

x(n,x 0 )=A (n,0)x 0 .<br />

The ma<strong>in</strong> result of this paper is to present an upper, and <strong>in</strong> some cases, a lower<br />

bound for norm of solution of system (1) by elements of matrices A(n). Estimation<br />

problem of the solutions of cont<strong>in</strong>uous l<strong>in</strong>ear systems <strong>in</strong> terms of the coefficients<br />

is discussed <strong>in</strong> literature (for example see [1], Chapter IV, §6). The <strong>auth</strong>or shows<br />

on examples that is impossible to judge objectively, which of the presented there<br />

estimates is <strong>in</strong> general better. This problem is also discussed <strong>in</strong> [3], [15] and [16].<br />

Estimation problem for the solution of dynamical systems is closely related to<br />

the concept of Lyapunov exponents. Now we present the def<strong>in</strong>itions.<br />

Let a =(a(n)) n∈N be a sequence of real numbers. The numbers (or the symbol<br />

±∞)def<strong>in</strong>edas<br />

1<br />

λ (a)=limsup<br />

n→∞ n ln|a(n)|<br />

is called the characteristic exponent of sequence (a(n)) n∈N .<br />

For x 0 ∈ R s ,x 0 ≠ 0 the Lyapunov exponent λ A (x 0 ) of (1) is def<strong>in</strong>ed as characteristic<br />

exponent of (‖x(n,x 0 )‖) n∈N , therefore<br />

1<br />

λ A (x 0 )=limsup<br />

n→∞ n ln‖x(n,x 0)‖.<br />

It is well known [4] that the set of all Lyapunov exponents of system (1) conta<strong>in</strong>s<br />

at most s elements, say −∞ < λ 1 (A) < λ 2 (A) < ... < λ r (A) < ∞, r ≤ s and the set<br />

{λ 1 (A),λ 2 (A),...,λ r (A)} is called the spectrum of (1).<br />

For exhaustive presentation of theory of Lyapunov exponents we recommend the<br />

follow<strong>in</strong>g literature positions: [2], [4]. Problem of estimation of Lyapunov exponents<br />

is discussed <strong>in</strong> [5]-[9], [12]-[14] and [18].<br />

In the paper we will also use the follow<strong>in</strong>g conclusion from publication [10] and<br />

[11].<br />

Theorem 1. Suppose, that for system (1) we have<br />

lim A(n)=A. (2)<br />

n→∞<br />

Then, Lyapunov exponents of system (1) co<strong>in</strong>cides with logarithms of moduli’s<br />

eigenvalues of matrix A.<br />

2 Ma<strong>in</strong>Results<br />

Let <strong>in</strong>troduce the follow<strong>in</strong>g notations:<br />

{<br />

aij (p) for i ≠ j<br />

a ij (p)=<br />

a ii (p) − 1fori = j , (3)

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