Search results for " space"
showing 10 items of 4562 documents
Computing variations of entropy and redundancy under nonlinear mappings not preserving the signal dimension: quantifying the efficiency of V1 cortex
2021
In computational neuroscience, the Efficient Coding Hypothesis argues that the neural organization comes from the optimization of information-theoretic goals [Barlow Proc.Nat.Phys.Lab.59]. A way to confirm this requires the analysis of the statistical performance of biological systems that have not been statistically optimized [Renart et al. Science10, Malo&Laparra Neur.Comp.10, Foster JOSA18, Gomez-Villa&Malo J.Neurophysiol.19]. However, when analyzing the information-theoretic performance, cortical magnification in the retina-cortex pathway poses a theoretical problem. Cortical magnification stands for the increase the signal dimensionality [Cowey&Rolls Exp. Brain Res.74]. Conventional mo…
General Theory: Topological Aspects
2009
In Chapter 1, we have analyzed the structure of pip-spaces from the algebraic point of view only, (i.e., the compatibility relation). Here we will discuss primarily the topological structure given by the partial inner product itself. The aim is to tighten the definitions so as to eliminate as many pathologies as possible. The picture that emerges is reassuringly simple: Only two types of pip-spaces seem sufficiently regular to have any practical use, namely lattices of Hilbert spaces (LHS) or Banach spaces (LBS), that we have introduced briefly in the Introduction. Our standard reference on locally convex topological vector spaces (LCS) will be the textbook of Kothe [Kot69]. In addition, fo…
Synchrotron x-ray transmission measurements and modeling of filters investigated for Athena
2020
International audience; Advanced Telescope for High-Energy Astrophysics is a large-class astrophysics space mission selected by the European Space Agency to study the theme "Hot and Energetic Universe." The mission essentially consists of a large effective area x-ray telescope and two detectors: the X-ray Integral Field Unit (X-IFU) and the Wide Field Imager (WFI). Both instruments require filters to shield from out-of-band radiation while providing high transparency to x-rays. The mission is presently in phase B; thus, to consolidate the preliminary design, investigated filter materials need to be properly characterized by experimental test campaigns. We report results from high-resolution…
Numerical Recovery of Source Singularities via the Radiative Transfer Equation with Partial Data
2013
The inverse source problem for the radiative transfer equation is considered, with partial data. Here we demonstrate numerical computation of the normal operator $X_{V}^{*}X_{V}$ where $X_{V}$ is the partial data solution operator to the radiative transfer equation. The numerical scheme is based in part on a forward solver designed by F. Monard and G. Bal. We will see that one can detect quite well the visible singularities of an internal optical source $f$ for generic anisotropic $k$ and $\sigma$, with or without noise added to the accessible data $X_{V}f$. In particular, we use a truncated Neumann series to estimate $X_{V}$ and $X_{V}^{*}$, which provides a good approximation of $X_{V}^{*…
LOCAL CONTROL OF SOUND IN STOCHASTIC DOMAINS BASED ON FINITE ELEMENT MODELS
2011
A numerical method for optimizing the local control of sound in a stochastic domain is developed. A three-dimensional enclosed acoustic space, for example, a cabin with acoustic actuators in given locations is modeled using the finite element method in the frequency domain. The optimal local noise control signals minimizing the least square of the pressure field in the silent region are given by the solution of a quadratic optimization problem. The developed method computes a robust local noise control in the presence of randomly varying parameters such as variations in the acoustic space. Numerical examples consider the noise experienced by a vehicle driver with a varying posture. In a mod…
Innovators and innovated: Newspapers and the postdigital future beyond the “death of print”
2017
Along with other cultural organizations, newspapers, through waves of digital disruption, have become subject to a dominant narrative of crisis. But newspapers have long participated in change. A constructivist approach, qualified by consideration of media materiality, draws attention to diverse but essential processes of innovation around them. We see a contraflow of migration from digital to print, opening up a shared media space; bonding strategies are bringing multimedia to ink on paper, while bridging via boundary objects such as QR (Quick Response) codes are connecting the two. Among other initiatives, development of automation of news production and experiments with transparency are …
Homing blogs as ambivalent spaces for feminine agency
2017
This article discusses a form of lifestyle blogging where women blog about their homes and everyday lives. In these homing blogs, selfrepresentations are characteristically spatially demarcated within the private sphere of the home. As these repeated representations of women in their homes take place in the public space of the internet, homing blogs work towards naturalizing the home as a women’s sphere. Written and commented on mostly by other women, homing blogs represent a feminine form of self-expression and communication that functions as a discursive expression of ongoing social, economic, and cultural changes in affluent Western societies. In this article, Finnish versions of these h…
L'espace de liberté comme mesure synthétique du développement territorial durable
2011
By discussing the concept of development itself, authors propose two synthetic indexes relying on estimation of potential: Development Space Value and Development Space Creation Under the weak hypothesis that any successful development improves future possibilities, changes in potential are a good development measure. In their path, authors show how development space is tied with freedom: a shrink in it results mechanically in indexes fall. So, "sustainable" and "economic" become two sides of same piece rather than enemies. Reliable in simulations, the approach is to be tested in real conditions, to verify full data availability and to secure calculating methods.
Il primo concorso per il Palazzo di Giustizia a Roma del 1884. Ricostruzione critica del progetto di Ernesto Basile
2019
1. Breve descrizione dell’oggetto di studio Il concorso del Palazzo di Giustizia di Roma si svolge in quattro fasi svolte tra il 1884 e il 1887. Il progetto per il primo concorso, del 1884, redatto dall’allora giovanissimo Ernesto Basile (Palermo 1857-1932), rivela una grande perizia progettuale che trasforma il complesso programma funzionale in un austero edificio in stile neofiorentino. I disegni originari dell’opera, non realizzata, conservati presso la Dotazione Basile del Dipartimento di Architettura dell’Università di Palermo, sono stati oggetto di studio propedeutico alle fasi di analisi, interpretazione e ricostruzione congetturale del modello digitale. 2. Stato dell’arte e riferime…
Violência, evasão e exclusão na educação superior
2019
The present text focuses on a relationship between higher education, institutional and symbolic violence and exclusion, practicing as a challenge based on reflections on the existence of evasion in Brazilian university. Ignoring the educational institution as a direct responsible for these things, this text considers that a logic in University organization and operation helps to enlarge inequalities that provide the mechanisms of evasion; at the same time, it presents itself as a space of reference and a struggle against social inequalities and violence. On a provisional basis, the text stands out that: depending on the execution of educational procedures and practices undertaken by the ins…