Mode (habillement) | EPFL Graph Search

thumb|Gisele Bündchen défilant en 2006. La mode (ou les modes), et plus précisément la mode vestimentaire, désigne la manière de se vêtir, conformément au goût d'une époque dans une région donnée. C'est un phénomène impliquant le collectif via la société, le regard qu'elle renvoie, les codes qu'elle impose et le goût individuel. La mode est l'une des plus puissantes industries du monde : elle représente 6% de la consommation mondiale et elle est en croissance constante. La mode concerne non seulement le vêtement mais aussi les accessoires, le maquillage, le parfum et même les modifications corporelles. Les facteurs déterminant la mode sont parfois une recherche esthétique (notamment pour les grands créateurs). Néanmoins, la mode est aussi déterminée par d'autres facteurs, pour ceux qui la suivent : un moyen d'affirmer son rang social, son groupe social, son pouvoir d'achat et sa personnalité ; ou bien pour les créateurs qui imitent, un moyen commode de gagner de l'argent et du su

Images des microcosmes flottants

Olivier Nicolas Meystre

This research focuses on the premise that depiction is quintessential to the conception of an architectural project. The representation also provides insights regarding how the architects design the architecture. This thesis is intended towards understanding new forms and paradigms of design mediation that have emerged over the last two decades in Japan. It unravels and highlights the historical, theoretical aspects and analyses the evolution, convergence and major trends in the field of architectural representation. Based on bibliographical sources and exclusive, unpublished interviews with the prominent Japanese architects of the period under consideration, this work presents six cross-functional themes with the objective to identify and examine the critical tools that could be used in the conception and representation of the contemporary Japanese architecture. The understanding of the underlying techniques reveal a very hybridised landscape of digital and analog tools with a paradoxical objective of imparting a manual effect to the entire expression. The treatment of light in the images of the project is characterised by overexposure and dispersion that adds an elusory, unseizable dimension to the objects and spatial limits. In a similar fashion, the graphical limits, are either diminished or diluted giving an impression of a space with evolving outlines. The pseudo-naive expression of multiple images, achieved by the profusion of familiar objects, obliterates the orthodox hierarchy among the architectural elements and opens up the possibility of evoking and imagining tiny, soothing universes in an architecture which is otherwise radical to the beholder. The point of view used in images transcend the Euclidean realism, producing an imagery that seems to float in free space. Finally, the genealogy of relationship between masters and students permits the tracing of the lines of influence, how the craftsmanship changed hands and percolated down the professional world. The specificities in the Japanese representation are a testimony to the complex approach of the architects towards an architectural project, where all the attributes of space are questioned and redefined but still the undercurrent of tradition continues to have a pivotal influence.

EPFL2015

Time-Varying Components for Enhancing Wireless Transfer of Power and Information

Romain Christophe Rémy Fleury, Mohammad Sajjad Mirmoosa, Xuchen Wang

Temporal modulation of components of electromagnetic systems provides an exceptional opportunity to engineer the response of those systems in a desired fashion, both in the time and frequency domains. For engineering time-modulated systems, one needs to thoroughly study the basic concepts and understand the salient characteristics of temporal modulation. In this paper, we carefully study physical models of basic bulk circuit elements—capacitors, inductors, and resistors—as frequency dispersive and time-varying components and study their effects in the case of periodical time modulations. We develop a solid theory for understanding these elements, and apply it to two important applications: wireless power transfer and antennas. For the first application, we show that, by periodically modulating the mutual inductance between the transmitter and receiver, the fundamental limits of classical wireless power transfer systems can be overcome. Regarding the second application, we consider a time-varying source for electrically small dipole antennas and show how time modulation can enhance the antenna performance. The developed theory of electromagnetic systems engineered by temporal modulation is applicable from radio frequencies to optical wavelengths.

2021

IMPROVED VARIANTS OF THE HUTCH plus plus ALGORITHM FOR TRACE ESTIMATION

Alice Cortinovis, Daniel Kressner, Ulf David Persson

This paper is concerned with two improved variants of the Hutch++ algorithm for estimating the trace of a square matrix, implicitly given through matrix-vector products. Hutch++ combines randomized low-rank approximation in a first phase with stochastic trace estimation in a second phase. In turn, Hutch++ only requires O (epsilon(-1)) matrix-vector products to approximate the trace within a relative error\varepsilon with high probability, provided that the matrix is symmetric positive semidefinite. This compares favorably with the O (epsilon(-2)) matrix-vector products needed when using stochastic trace estimation alone. In Hutch++, the number of matrix-vector products is fixed a priori and distributed in a prescribed fashion among the two phases. In this work, we derive an adaptive variant of Hutch++, which outputs an estimate of the trace that is within some prescribed error tolerance with a controllable failure probability, while splitting the matrix-vector products in a near-optimal way among the two phases. For the special case of a symmetric positive semidefinite matrix, we present another variant of Hutch++, called Nystrom++, which utilizes the so-called Nystrom approximation and requires only one pass over the matrix, as compared to two passes with Hutch++. We extend the analysis of Hutch++ to Nystrom++. Numerical experiments demonstrate the effectiveness of our two new algorithms.

SIAM PUBLICATIONS2022

Images des microcosmes flottants

Olivier Nicolas Meystre

EPFL2015