A modified broadcast strategy for distributed signal estimation in a wireless sensor network with a tree topology

We envisage a wireless sensor network (WSN) where each node is tasked with estimating a set of node-specific desired signals that has been corrupted by additive noise. The nodes accomplish this estimation by means of the distributed adaptive node-specific estimation (DANSE) algorithm in a tree topology (T-DANSE). In this paper, we consider a network where there is at least one node with a large (virtually infinite) energy budget, which we select as the root node. We propose a modification to the signal flow of the T-DANSE algorithm where instead of each node having two-way signal communication, there is a single signal flow toward the root node of the tree topology which then broadcasts a single signal to all other nodes. We demonstrate that the modified algorithm is equivalent to the original T-DANSE algorithm in terms of the signal estimation performance, shifts a large part of the communication burden toward the high-power root node to reduce the energy consumption in the low-power nodes and reduces the input-output delay

La danse et ses représentations sociales: quels sont les écarts représentationnels entre les personnes pratiquant une activité de danse et celles ne la pratiquant pas ? Quels sont les écarts représentationnels entre les adolescents et jeunes adultes et les messages véhiculés par les films populaires sur la danse ?

Depuis plusieurs années déjà, les médiums artistiques commencent à se faire plus présents au sein des foyers, des homes, des hôpitaux et autres institutions dans le domaine du social ou de la santé. Cependant, la danse est encore aujourd’hui peu utilisée en tant que médium artistique dans nos pays européens (Diane Jean-Sloninski, 2013 : 11). Lorsqu’elle est utilisée en tant que pratique artistique auprès d’institutions, la danse suscite parfois de vives réactions (Guérandel, 2013 : 33). J’ai souvent entendu des constats de la part de mon entourage ou même d’inconnus. Certains ne comprennent pas pourquoi la danse plaît. Il est souvent difficile de percevoir les bénéfices qu’elle peut apporter à un individu ou à un groupe et certains ne pensent d’ailleurs même pas que la danse est une activité sportive. Il est aussi souvent pensé que cette activité est plutôt réservée à la gente féminine. A travers cette recherche je veux découvrir pourquoi les jeunes n’ayant jamais pratiqué la danse sont si peu ouverts à tenter l’expérience. Quels sont les écarts de représentation entre les personnes ayant déjà pratiqué la danse et les inexpérimentés ? Sur quelle base se construit leur discours ? Et quelle image se véhicule-t-il sur la danse aujourd’hui ? J’ai donc effectué une analyse au sujet des représentations sociales des jeunes âgés de 15 à 23 ans et découvert quels bénéfices l’activité « danse » peut apporter au champ du travail social. Pour récolter des données pertinentes, j’ai utilisé le récit auprès des jeunes afin d’influencer le moins possibles leurs propos. Je vais aussi analyser le film ayant fait le plus d’entrée en Suisse ces dix dernières années et qui a comme sujets principaux la danse et la jeunesse. De l’analyse des récits récoltés et du film visionné, j’ai pu faire émerger les noyaux centraux et les éléments périphériques ainsi que les fonctions de la représentation sociale au sujet de la danse de ces différentes catégories de recherche. Diverses thématiques sociales ont aussi été mises en lien avec l’activité « danse ». Toute cette analyse me servira de prémices théoriques au développement d’un agir et d’un discours personnalisés afin d’être efficace sur le terrain lors de la création d’ateliers de danse dans mon futur professionnel

Quantum Gibbs distribution from dynamical thermalization in classical nonlinear lattices

We study numerically time evolution in classical lattices with weak or moderate nonlinearity which leads to interactions between linear modes. Our results show that in a certain strength range a moderate nonlinearity generates a dynamical thermalization process which drives the system to the quantum Gibbs distribution of probabilities, or average oscillation amplitudes. The effective dynamical temperature of the lattice varies from large positive to large negative values depending on energy of initially excited modes. This quantum Gibbs distribution is drastically different from usually expected energy equipartition over linear modes corresponding to a regime of classical thermalization. Possible experimental observations of this dynamical thermalization are discussed for cold atoms in optical lattices, nonlinear photonic lattices and optical fiber arrays.Comment: 15 pages, 12 figures. Small modifs., video abstract 107MB at http://www.quantware.ups-tlse.fr/dima/video/gibbs2013.mp

Boston University Symphony Orchestra, September 25, 2008

This is the concert program of the Boston University Symphony Orchestra performance on Thursday, September 25, 2008 at 7:30 p.m., at the Tsai Performance Center, 685 Commonwealth Avenue, Boston, Massachusetts. Works performed were "Sarabande" from Pour le Piano and "Danse" from Tarantelle styrienne by Claude Debussy and Maurice Ravel, Concertino for Trumpet and Orchestra by Richard Cornell, and Symphony No. 2 in D major, Op. 73 by Johannes Brahms. Digitization for Boston University Concert Programs was supported by the Boston University Center for the Humanities Library Endowed Fund

Kolmogorov turbulence, Anderson localization and KAM integrability

The conditions for emergence of Kolmogorov turbulence, and related weak wave turbulence, in finite size systems are analyzed by analytical methods and numerical simulations of simple models. The analogy between Kolmogorov energy flow from large to small spacial scales and conductivity in disordered solid state systems is proposed. It is argued that the Anderson localization can stop such an energy flow. The effects of nonlinear wave interactions on such a localization are analyzed. The results obtained for finite size system models show the existence of an effective chaos border between the Kolmogorov-Arnold-Moser (KAM) integrability at weak nonlinearity, when energy does not flow to small scales, and developed chaos regime emerging above this border with the Kolmogorov turbulent energy flow from large to small scales.Comment: 8 pages, 6 figs, EPJB style

Riding the wave: high prices, big business? : the role of multinationals in the international grain markets

In 2007-2008, world market prices for grains and inputs such as fertiliser have risen sharply. At the same time, international trade is increasingly dominated by only a few large agribusiness firms. Civil society organisations are increasingly concerned about the potential impact of these two trends. This report provides an overview of the international trade of grains, the role of multinationals that trade in international grains, and the linkage of international and domestic grain markets in Africa. This research also provides an analysis of the role of multinationals and speculation on grain price

Technological learning for innovating towards sustainable cultivation practices: the Vietnamese smallholder rose sector

Deregulation and globalisation has altered the views of public involvement in development and led to strategies focusing on private sector participation. An implicit assumption seems to be that these linkages will enhance the technological capacity of smallholder producers by way of more cost-efficient technologies trickling down through the value chain or by quality requirements inducing best practices. The argument put forward in this paper is that sustainable non traditional agricultural chain development requires more purposeful actions and institutional transitions, both in the public and private spheres, targeting improved upstream innovative capacities. Empirical findings from a Dutch-Vietnamese partnership on sustainable floriculture development are used. Research revealed that the pest and disease control solutions applied by smallholder rose growers were incremental adaptations of experiences obtained in former food crop cultivation practices. Floriculture however may require more drastic changes in cultivation practices to make the sector more environmentally benign. In the case of smallholder Vietnamese flower producers, this implies adaptation of knowledge and skills currently not present. An important hindrance in promoting this knowledge and skills appears to be the weak vertical linkages between flower growers and public and private research and development organizations

The Dies Irae ( Day of Wrath ) and Totentanz ( Dance of Death ): Medieval Themes Revisited in 19th Century Music and Culture

During the pivotal November 2002 football game of Arkansas vs. Georgia in the SEC conference championship, the Georgia marching band struck up their defensive rallying song. Instead of a typical defense song, the band played an excerpt of the Gregorian Sequence Dies Irae ( Day of Wrath\u27\u27) from the Roman Catholic Requiem Mass. Drastically dissociated from its original medieval milieu, this musical Sequence still manages to elicit the same effect of fear and foreboding nearly a thousand years later. Precisely because of its deep musical and cultural roots, the Dies Irae occupies a significant place in history, closely intertwined from early on with the medieval folk motif Totentanz ( Dance of Death ), widely depicted in medieval art, and dramatically revived in 19th century music, art, and literature. This multi-disciplinary study focuses on the history of art and music of these two medieval themes during their development, and then moves on to study them in 19th century culture. Specifically, the manipulation of the original Gregorian chant and the incorporation of the idea of a medieval dance are analyzed in the music of Hector Berlioz, Franz Liszt, and Camille Saint-Saens. Numerous other contextual links are explored as well, such as Johann Wolfgang von Goethe, Victor Hugo, Henri Cazalis, William Blake, and Alfred Rethel, all of whom created 19th century artistic or literary masterpieces derived from the thematic seeds of the Dies Irae and the Totentanz. Although neither of these ideas endured in their original form during the Romantic era, the inherently compelling nature of these themes that center on the macabre but inevitable end of life captivated the Romantic geniuses and continue to intrigue us to this day