Search results for "FRACTALS"
showing 10 items of 40 documents
Fractal dimension versus density of built-up surfaces in the periphery of Brussels
2007
International audience; This paper aims at showing the usefulness of the fractal dimension for characterizing the spatial structure of the built-up surfaces within the periurban fringe. We first discuss our methodology and expectations in terms of operationality of the fractal dimension theoretically and geometrically. An empirical analysis is then performed on the southern periphery of Brussels (Brabant Wallon). The empirical analysis is divided into two parts: first, the effect of the size and shape of the windows on the fractal measures is empirically evaluated; this leads to a methodological discussion about the importance of the scale of analysis as well as the real sense of fractality…
Aspects fractals de la morphologie urbaine
1994
National audience
Fingerprinting white marbles of archaeometric interest by means of combined SANS and USANS
2007
We have performed a series of USANS and SANS measurements on a selected group of marble samples characterized by similar chemical composition but wide range of known metamorphic conditions. With these samples we start the building up of a data base in an attempt to correlate metamorphism and mesoscopic structure of white marbles. Experimental data have been analysed in terms of a hierarchical model. The present data highlight the importance of the structure at meso scale in identifying the provenance of the marble samples. A remarkable simple relation between the model parameters and the metamorphic degree has been found. This curve might represent a master curve to allow fingerprinting of …
Long-term memories of developed and emerging markets: Using the scaling analysis to characterize their stage of development
2005
The scaling properties encompass in a simple analysis many of the volatility characteristics of financial markets. That is why we use them to probe the different degree of markets development. We empirically study the scaling properties of daily Foreign Exchange rates, Stock Market indices and fixed income instruments by using the generalized Hurst approach. We show that the scaling exponents are associated with characteristics of the specific markets and can be used to differentiate markets in their stage of development. The robustness of the results is tested by both Monte-Carlo studies and a computation of the scaling in the frequency-domain.
Alterations of panoramic radiomorphometric indices in children and adolescents with beta-thalassemia major: A fractal analysis study
2021
Background Beta-thalassemia major is an inherited disorder that can cause bone deformity and loss of bone mineral density. The objective of this study is to evaluate the cortical and trabecular mandibular bone morphology of children and adolescents who have beta-thalassemia major (ß-TM) using a fractal dimension (FD) analysis and different panoramic radiomorphometric indices with digital panoramic radiographic images (DPRIs). Material and Methods The study included 80 patients (with 40 patients each of ß-TM and control). The mandibular cortical width (MCW), panoramic mandibular index (PMI), mandibular cortical index (MCI), and simple visual estimation (SVE) were evaluated, and an FD analysi…
Dimension of projection : Marstrand's theorem
2022
Tässä tutkielmassa todistetaan Marstrandin projektiolause käyttäen apuna potentiaaliteoriaa. Projektiolauseen mukaan 2-ulotteisen Borel joukon ortogonaaliprojektion Hausdorffin dimensio on luvun 1 ja kyseisen Borel joukon dimension minimi melkein kaikkiin eri suuntiin. Intuitiivisesti lause kertoo, että joukon varjon dimensio on suurin mahdollinen. Marstrandin projektiolauseen todistamiseksi tutkielmassa rakennetaan teoria alkaen yleisen mittateorian perustuloksista. Mittateorian pohjalta määritellään Hausdorffin mitta, jonka avulla määritellään joukon Hausdorffin dimensio. Intuitiivisesti Hausdorffin dimensio kuvaa joukon geometrista kokoa ja se on yksikäsitteinen jokaiselle joukolle. Haus…
Simulation de scénarios fractals d’urbanisation et des mobilités quotidiennes résultantes
2017
International audience
Mathematical and Coding Lessons Based on Creative Origami Activities
2019
AbstractThis paper considers how creativity and creative activities can be encouraged in regular mathematical classes by combining different teaching approaches and academic disciplines. We combined origami and paper folding with fractals and their mathematical properties as well as with coding in Scratch in order to facilitate learning mathematics and computer science. We conducted a case study experiment in a Serbian school with 15 high school students and applied different strategies for learning profound mathematical and coding concepts such as fractals dimension and recursion. The goal of the study was to employ creative activities and examine students’ activities during this process i…
DEVELOPMENT OF SUSTAINABLE METROPOLITAN AREAS USING A MULTI-SCALE DECISION SUPPORT SYSTEM
2012
A sustainable and sustaining planning strategy is globally important for metropolitan areas. Sustainable planning addresses the development of strategies to reduce the use of resources, increase economic efficiency and improve integration of social aspects. In contrast, splinter development (e.g. urban sprawl) involves damage to nature and generation of an increasing volume of traffic (these are the main criticisms following a study by Newman and Kenworthy (1989) on the relationship between settlement density and energy consumption). Interestingly, the overly compact city also has this effect as it may generate traffic flows for accessing green and leisure areas, or changes of residence due…
Simulating and assessing prospective scenarios
2008
The first part of the paper is centered on the phenomena of urban growth, in order to set the rules for a sustainable scenario of urban development. Then we enter the core of the paper that is the comparison of models. For each of the three compared models, we describe its main theoretical characteristics, the chosen parameters, and the obtained results. In section 6, heterogeneity of the produced results is discussed, and we highlight the points of interest and the lacks of the three models. Here we show that results we obtained feed debates about urban growth management. Finally, concluding remarks at the end of the paper address the general topic of the evaluation of the quality of simul…