Search results for "fraktaalit"
showing 10 items of 14 documents
Isometric embeddings of snowflakes into finite-dimensional Banach spaces
2016
We consider a general notion of snowflake of a metric space by composing the distance by a nontrivial concave function. We prove that a snowflake of a metric space $X$ isometrically embeds into some finite-dimensional normed space if and only if $X$ is finite. In the case of power functions we give a uniform bound on the cardinality of $X$ depending only on the power exponent and the dimension of the vector space.
Combinatorial proofs of two theorems of Lutz and Stull
2021
Recently, Lutz and Stull used methods from algorithmic information theory to prove two new Marstrand-type projection theorems, concerning subsets of Euclidean space which are not assumed to be Borel, or even analytic. One of the theorems states that if $K \subset \mathbb{R}^{n}$ is any set with equal Hausdorff and packing dimensions, then $$ \dim_{\mathrm{H}} π_{e}(K) = \min\{\dim_{\mathrm{H}} K,1\} $$ for almost every $e \in S^{n - 1}$. Here $π_{e}$ stands for orthogonal projection to $\mathrm{span}(e)$. The primary purpose of this paper is to present proofs for Lutz and Stull's projection theorems which do not refer to information theoretic concepts. Instead, they will rely on combinatori…
Fraktaalien luominen tietokoneella
2016
Tässä tutkielmassa esitellään muutamia tunnettuja menetelmiä Mandelbrotin ja Julian joukkojen ja iteroitujen funktiojärjestelmien luontiin. This paper presents some known methods for generating Mandelbrot and Julia sets and iterated function systems.
On the Dimension of Kakeya Sets in the First Heisenberg Group
2021
We define Kakeya sets in the Heisenberg group and show that the Heisenberg Hausdorff dimension of Kakeya sets in the first Heisenberg group is at least 3. This lower bound is sharp since, under our definition, the $\{xoy\}$-plane is a Kakeya set with Heisenberg Hausdorff dimension 3.
Hidden Strange Nonchaotic Attractors
2021
In this paper, it is found numerically that the previously found hidden chaotic attractors of the Rabinovich–Fabrikant system actually present the characteristics of strange nonchaotic attractors. For a range of the bifurcation parameter, the hidden attractor is manifestly fractal with aperiodic dynamics, and even the finite-time largest Lyapunov exponent, a measure of trajectory separation with nearby initial conditions, is negative. To verify these characteristics numerically, the finite-time Lyapunov exponents, ‘0-1’ test, power spectra density, and recurrence plot are used. Beside the considered hidden strange nonchaotic attractor, a self-excited chaotic attractor and a quasiperiodic at…
Self-affine sets in analytic curves and algebraic surfaces
2018
We characterize analytic curves that contain non-trivial self-affine sets. We also prove that compact algebraic surfaces do not contain non-trivial self-affine sets. peerReviewed
On a Continuous Sárközy-Type Problem
2022
Abstract We prove that there exists a constant $\epsilon> 0$ with the following property: if $K \subset {\mathbb {R}}^2$ is a compact set that contains no pair of the form $\{x, x + (z, z^{2})\}$ for $z \neq 0$, then $\dim _{\textrm {H}} K \leq 2 - \epsilon $.
Johdatus fraktaaliderivaattoihin ja niiden sovelluksiin
2014
Fraktaaliderivaatta on derivaatta, jonka kertaluku on reaali- tai kompleksiluku. Fraktaaliderivaatta voidaan määritellä usealla eri tavalla, mutta mikään määritelmä ei ole selkeästi muita parempi. Koska fraktaaliderivaatan ominaisuudet riippuvat valitusta määritelmästä, ominaisuuksia ei voida suoraan yleistää kaikille fraktaaliderivaatoille. Tämän tutkielman tarkoitus on antaa lukijalle perustiedot reaalilukukertaisista fraktaaliderivaatoista ja niiden määritelmäsidonnaisista ominaisuuksista. Tutkielmassa esitellään kolme yleisimmin viitattua määritelmää: Grünwald-Letnikov, Riemann-Liouville ja Caputo. Grünwald-Letnikovin määritelmä yleistää klassisen derivaatan määritelmän suoraan reaali- …