6,558 research outputs found
The Twilight of “Chimerica”? China and the collapse of the American model
“Chimerica” illustrates the interactions between a Chinese model of high savings, overinvestment and export-led growth and the American model of leverage investment, credit consumption and finance-led growth. The collapse of the U.S model, linked with the unregulated derivatives market, drives China to redirect its growth toward domestic consumption, despite the strengthening of regionalisation in East Asia. The new stimulus plan, based on investment, is limited by both income disparities and the under-development of social protection. Land reform, or the collective redistribution of the remaining state assets, could stimulate domestic consumption. But the first solution deprives the local state of financial resources, and the second solution collides with the interests of the state-party system. However, stronger social movements could lead to a better income distribution. Like two faces of the same coin, credit consumption or high savings rate reflect the crisis of a global accumulation regime, tailored for a financial oligarchy in the U.S, or for a party-state oligarchy in China.World Financial crisis, World Economic crisis, China, Usa
Gain scheduled flight control law for a flexible aircraft : A practical approach
Abstract: This paper presents a gain-scheduling method applied to flight control law design. The method is a stabilitypreservinginterpolation technique ofexisting
controllers under observer-state feedback form. Application is made on a flexible civil aircraft example considering multiple scheduling parameters. Although the interpolation technique gives powerful a priori stability guarantees, the sufficient condition to satisfy leads to conservative results in practice. We thus use a fixed observer model and check stability andperformance thanks to μ-analysis. Provided results are really satisfactory for a final controller of little complexity
Bayesian power-spectrum inference with foreground and target contamination treatment
This work presents a joint and self-consistent Bayesian treatment of various
foreground and target contaminations when inferring cosmological power-spectra
and three dimensional density fields from galaxy redshift surveys. This is
achieved by introducing additional block sampling procedures for unknown
coefficients of foreground and target contamination templates to the previously
presented ARES framework for Bayesian large scale structure analyses. As a
result the method infers jointly and fully self-consistently three dimensional
density fields, cosmological power-spectra, luminosity dependent galaxy biases,
noise levels of respective galaxy distributions and coefficients for a set of a
priori specified foreground templates. In addition this fully Bayesian approach
permits detailed quantification of correlated uncertainties amongst all
inferred quantities and correctly marginalizes over observational systematic
effects. We demonstrate the validity and efficiency of our approach in
obtaining unbiased estimates of power-spectra via applications to realistic
mock galaxy observations subject to stellar contamination and dust extinction.
While simultaneously accounting for galaxy biases and unknown noise levels our
method reliably and robustly infers three dimensional density fields and
corresponding cosmological power-spectra from deep galaxy surveys. Further our
approach correctly accounts for joint and correlated uncertainties between
unknown coefficients of foreground templates and the amplitudes of the
power-spectrum. An effect amounting up to percent correlations and
anti-correlations across large ranges in Fourier space.Comment: 15 pages, 11 figure
Experimental evidence of percolation phase transition in surface plasmons generation
Carrying digital information in traditional copper wires is becoming a major
issue in electronic circuits. Optical connections such as fiber optics offers
unprecedented transfer capacity, but the mismatch between the optical
wavelength and the transistors size drastically reduces the coupling
efficiency. By merging the abilities of photonics and electronics, surface
plasmon photonics, or 'plasmonics' exhibits strong potential. Here, we propose
an original approach to fully understand the nature of surface electrons in
plasmonic systems, by experimentally demonstrating that surface plasmons can be
modeled as a phase of surface waves. First and second order phase transitions,
associated with percolation transitions, have been experimentally observed in
the building process of surface plasmons in lattice of subwavelength apertures.
Percolation theory provides a unified framework for surface plasmons
description
Extra energy coupling through subwavelength hole arrays via stochastic resonance
Interaction between metal surface waves and periodic geometry of
subwavelength structures is at the core of the recent but crucial renewal of
interest in plasmonics. One of the most intriguing points is the observation of
abnormal strong transmission through these periodic structures, which can
exceed by orders of magnitude the classical transmission given by the filling
factor of the plate. The actual paradigm is that this abnormal transmission
arises from the periodicity, and then that such high transmission should
disappear in random geometries. Here, we show that extra energy can be coupled
through the subwavelength structure by adding a controlled quantity of noise to
the position of the apertures. This result can be modelled in the statistical
framework of stochastic resonance. The evolution of the coupled energy with
respect to noise gives access to the extra energy coupled at the surface of the
subwavelength array.Comment: 12 page
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