1,543,021 research outputs found
Information/disturbance trade-off in single and sequential measurements on a qudit signal
No full textWe address the trade-off between information gain and state disturbance in measurement performed on qudit systems and devise a class of optimal measurement schemes that saturate the ultimate bound imposed by quantum mechanics to estimation and transmission fidelities. The schemes are minimal, i.e. they involve a single additional probe qudit, and optimal, i.e. they provide the maximum amount of information compatible with a given level of disturbance. The performances of optimal single-user schemes in extracting information by sequential measurements in a N-user transmission line are also investigated, and the optimality is analyzed by explicit evaluation of fidelities. We found that the estimation fidelity does not depend on the number of users, neither for single-measure inference nor for collective one, whereas the transmission fidelity decreases with N. The resulting trade-off is no longer optimal and degrades with increasing N. We found that optimality can be restored by an effective preparation of the probe states and present explicitly calculations for the 2-user case
Compte administratif de l'exercice ..., compte de la gestion ..., et budget de l'exercice ... / Ville de Paris
No full textVariante(s) de titre : Compte administratif de l'exercice ..., et budget de l'exercice ... (Ville de Paris)Variante(s) de titre : Compte des recettes et dépenses de ..., et budget de l'exercice ... (Ville de Paris)Variante(s) de titre : Compte général de l'administration des finances de la ville de Paris ... et budget de l'exercice ...Etat de collection : 1827-1830Contient une table des matièresAvec mode text
Development of a popular style in commercial places : the example of tati shops in Paris
No full textThe author examines the so-called "popular" shopping networks and facilities. Taking the example of
the Tati stores in Barbès, in the 18th district of Paris, she examines the social and historic conditions of the
development of this brand, and offers an analysis of the different types of social relations at work at Tati in
particular and Barbes in general. Lastly, she demonstrates how this particular social environment
contributed to the arrival of "popular-chic" in the nineties.Quelles formes prennent les dispositifs marchands dits «populaires»? À partir de l'exemple des magasins Tati de Barbès, dans le 18e arrondissement de Paris, l'article examine les conditions sociales et historiques du développement de cette enseigne et propose une analyse des modes de sociabilité à l'oeuvre chez Tati en particulier et à Barbès en général. Il montre enfin en quoi cet espace social particulier a contribué, dans les années 1990, à l'avènement du « chic-popu »
Nonlinearity as a resource for nonclassicality in anharmonic systems
Get PDFNonclassicality is a key ingredient for quantum enhanced technologies and experiments involving macro- scopic quantum coherence. Considering various exactly-solvable quantum-oscillator systems, we address the role played by the anharmonicity of their potential in the establishment of nonclassical features. Specifically, we show that a monotonic relation exists between the the entropic nonlinearity of the considered potentials and their ground state nonclassicality, as quantified by the negativity of the Wigner function. In addition, in order to clarify the role of squeezing--which is not captured by the negativity of the Wigner function--we focus on the Glauber-Sudarshan P-function and address the nonclassicality/nonlinearity relation using the entanglement potential. Finally, we consider the case of a generic sixth-order potential confirming the idea that nonlinearity is a resource for the generation of nonclassicality and may serve as a guideline for the engineering of quantum oscillators
M.G. Mara, Evangile de Pierre, introduction, texte critique, traduction, commentaire et index. « Sources chrétiennes », n° 201. Paris, Cerf, 1973
No full textTrocmé Étienne. M.G. Mara, Evangile de Pierre, introduction, texte critique, traduction, commentaire et index. « Sources chrétiennes », n° 201. Paris, Cerf, 1973. In: Revue d'histoire et de philosophie religieuses, 54e année n°3,1974. p. 428
M.G. Mara, Evangile de Pierre, introduction, texte critique, traduction, commentaire et index. « Sources chrétiennes », n° 201. Paris, Cerf, 1973
No full textTrocmé Étienne. M.G. Mara, Evangile de Pierre, introduction, texte critique, traduction, commentaire et index. « Sources chrétiennes », n° 201. Paris, Cerf, 1973. In: Revue d'histoire et de philosophie religieuses, 54e année n°3,1974. p. 428
Turner, M.G. (Editor). — Landscape Heterogeneity and Disturbance. Springer-Verlag, Berlin, Heidelberg, New York, London, Paris and Tokyo, 1987
No full textBourlière François. Turner, M.G. (Editor). — Landscape Heterogeneity and Disturbance. Springer-Verlag, Berlin, Heidelberg, New York, London, Paris and Tokyo, 1987. In: Revue d'Écologie (La Terre et La Vie), tome 43, n°4, 1988. p. 413
Deterioration of mental health and insufficient Covid-19 information among disadvantaged immigrants in the greater Paris area
No full textObjectives
The aim of this study is to provide information on changes in mental health among disadvantaged immigrants from Sub-Saharan Africa in the Greater Paris area and their level of information about Covid-19.
Methods
Prior to the Covid-19 epidemic, the Makasi community-based cohort followed 850 immigrants from sub-Saharan Africa in the Greater Paris area. Between the 1st of April and the 7th of June 2020, all participants scheduled for a follow-up survey were systematically included into an additional COVID-19-related wave of data collection (N = 100). We compared participants' type of housing, level of food insecurity, work and mental health (PHQ9) before and during the first COVID-19-related lockdown, using paired-Mc Nemar chi-2 tests. We next described their level of information on Covid-19 and policy measures, broken down by sex.
Results
Among the 100 participants, 68% had no legal residence permit. Food insecurity was more often reported during lockdown than before (62% vs 52%). 9% of participants had a score indicative of severe depression (PHQ9) before lockdown and 17% afterwards (p = 0.17). Only 51% knew about the possibility of asymptomatic transmission of the COVID-19 virus.
Conclusions
This study brings original information on a hard-to-reach population group. Our results suggest that the lockdown had a detrimental impact on various economic and mental health aspects among disadvantaged migrants residing in the Greater Paris area
Quantifying the non Gaussian character of a quantum state by quantum relative entropy
No full textWe introduce a measure to quantify the non-Gaussian character of a quantum state: the quantum relative entropy between the state under examination and a reference Gaussian state. We analyze in detail the properties of our measure and illustrate its relationships with relevant quantities in quantum information such as the
Holevo bound and the conditional entropy; in particular, a necessary condition for the Gaussian character of a quantum channel is also derived. The evolution of non-Gaussianity is analyzed for quantum states undergoing
conditional Gaussification toward twin beams and de-Gaussification driven by Kerr interaction. Our analysis allows us to assess non-Gaussianity as a resource for quantum information and, in turn, to evaluate the performance of Gaussification and de-Gaussification protocols
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