Search results for "spheres"
showing 10 items of 329 documents
ConformalALU: A Conformal Geometric Algebra Coprocessor for Medical Image Processing
2015
Medical imaging involves important computational geometric problems, such as image segmentation and analysis, shape approximation, three-dimensional (3D) modeling, and registration of volumetric data. In the last few years, Conformal Geometric Algebra (CGA), based on five-dimensional (5D) Clifford Algebra, is emerging as a new paradigm that offers simple and universal operators for the representation and solution of complex geometric problems. However, the widespread use of CGA has been so far hindered by its high dimensionality and computational complexity. This paper proposes a simplified formulation of the conformal geometric operations (reflections, rotations, translations, and uniform …
Designing Atmospheres. The Role of Aesthetics in the Requalification of Space
2017
The ecological movements of the seventies gave environmental questions the role of key issues in the artistic, architectural and philosophical debate. However, these questions have been mainly dealt with an ecological and scientific approach. It was seldom noticed that both natural and built spaces can be above all conceived of as felt spaces and, furthermore, that their aesthetic qualities are as important as toxicological factors. Although it focussed on the environmental protection and on the harmonious integration of built-up and natural areas, the architectural reflection considers beauty a subordinate factor rather than a prime concern. Although during the recent years it has come bac…
The power of the gift: a perspective of political aesthetics
2019
According to Aristotle (Polit. 1253a) man is a “political animal” and his aim is to live in the community. Guided by this Aristotelian premise, I would like to dwell on the relevance of a relationship among individuals as the foundation of a civil society and the building of a political space. Following the Aristotelian perspective, the relationship among people acquires a political value in reference to the Greek word polis (city). Consequently, the adjective “political” indicates an idea wider than usually acknowledged and may refer to space, objects, and overall relationships among people. According to the natural model originally advocated by Aristotle, the urban space acquires a politi…
Aesthetic Perspectives on Culture, Politics, and Landscape. Appearances of the “Political”
2022
This book investigates how we are involved in politically informed structures and how they appear to us. Following different approaches in contemporary aesthetics and cultural philosophy, such as everyday aesthetics, atmosphere and aestheticization, the authors explore how embedded powers in politics, education, democracy, and landscape are analyzed through aesthetics.
Artificare lo spazio urbano. Lo sguardo “altro” di Danisinni
2019
Se nella città di Palermo, come in altre città italiane e del mondo, l’incompiuto è segno di un percorso trasformativo che ha subito un arresto, nel rione palermitano di Danisinni l’incompiuto è simbolo di una dimensione esistenziale. Infatti, non solo dal punto di vista topografico, ma anche da quello economico e sociale Danisinni costituisce un mondo chiuso in sé stesso: è un villaggio dentro la città, ma al contempo è un luogo periferico e marginale, tagliato anche dai collegamenti pubblici. Tuttavia negli ultimi anni in questo quartiere sono stati avviati dei processi di riqualificazione urbana che hanno fatto ricorso alle arti da strada (murales, spettacoli teatrali e circensi). Il sag…
Optical tweezing using tunable optical lattices along a few-mode silicon waveguide
2018
International audience; Fourteen years ago, optical lattices and holographic tweezers were considered as a revolution, allowing for trapping andmanipulating multiple particles at the same time using laser light. Since then, near-field optical forces have arousedtremendous interest as they enable efficient trapping of a wide range of objects, from living cells to atoms, in integrateddevices. Yet, handling at will multiple objects using a guided light beam remains a challenging task for current on-chipoptical trapping techniques. We demonstrate here on-chip optical trapping of dielectric microbeads and bacteria usingone-dimensional optical lattices created by near-field mode beating along a f…
Computing the Arrangement of Circles on a Sphere, with Applications in Structural Biology
2009
International audience; Balls and spheres are the simplest modeling primitives after affine ones, which accounts for their ubiquitousness in Computer Science and Applied Mathematics. Amongst the many applications, we may cite their prevalence when it comes to modeling our ambient 3D space, or to handle molecular shapes using Van der Waals models. If most of the applications developed so far are based upon simple geometric tests between balls, in particular the intersection test, a number of applications would obviously benefit from finer pieces of information. Consider a sphere $S_0$ and a list of circles on it, each such circle stemming from the intersection between $S_0$ and another spher…
Dosimetry comparison between TG-43 and Monte Carlo calculations using the Freiburg flap for skin high-dose-rate brachytherapy
2012
Abstract Purpose The purpose of this work was to evaluate whether the delivered dose to the skin surface and at the prescription depth when using a Freiburg flap applicator is in agreement with the one predicted by the treatment planning system (TPS) using the TG-43 dose-calculation formalism. Methods and Materials Monte Carlo (MC) simulations and radiochromic film measurements have been performed to obtain dose distributions with the source located at the center of one of the spheres and between two spheres. Primary and scatter dose contributions were evaluated to understand the role played by the scatter component. A standard treatment plan was generated using MC- and TG-43-based TPS appl…
Cuerpos moldeables y vidas modulables: La invención del estado holísticamente saludable como bienestar (integral)
2020
The article argues ?from the Deleuzian concepts of society of control, moulding and modulation and the Rosean theory on the economization and medicalization of life? that the expansion of the concept of health in terms of integral and subjective well-being is the effect of a socio-historical shift in the way we relate to this signifier, and therefore to our bodies and ourselves. We use this interpretative network to analyze the effects that the biopsychosocial health paradigm has had in the context of aesthetic surgery and fitness practice. As a result, we see that the expansion of the concept of health has extended the domain of medicine into the spheres of personal care and physical appea…
Design of the CGAL Spherical Kernel and application to arrangements of circles on a sphere
2009
International audience; This paper presents a CGAL kernel for algorithms manipulating 3D spheres, circles, and circular arcs. The paper makes three contributions. First, the mathematics underlying two non trivial predicates are presented. Second, the design of the kernel concept is developed, and the connexion between the mathematics and this design is established. In particular, we show how two different frameworks can be combined: one for the general setting, and one dedicated to the case where all the objects handled lie on a reference sphere. Finally, an assessment about the efficacy of the \sk\ is made through the calculation of the exact arrangement of circles on a sphere. On average …