Profits, Confidence and public deficits: modeling Minsky's institutional dynamics

The aim of this paper is to present a “Minskian” model which explicitly deals with the influence of the institutional dynamics on the relation between finance, investment and economic fluctuations. First, the Minskian foundations of the proposed analytical framework are highlighted. Second the dynamical properties of the model are studied, drawing the inferences of a stabilization policy. It is shown that the economy is unstable when the budget policy is not very sensitive to variations in private investment. On the contrary, when, the counter cyclical deficit constraint is flexible enough, the economy is stabilized. These results, that echo recent debates and proposals on budget deficits rules in the EMU, are fully consistent with the way Minsky considers that public authorities may “stabilize an unstable economy”.Minsky, financial instability, confidence, public deficits

Banque coloniales, crédit et circulation: l'exemple de la Martinique 1848-1871

Cette contribution s'intéresse au fonctionnement de la banque de la Martinique dans la période de transition qui a suivi l'abolition de l'esclavage. L'article souligne le succès mitigé de cette institution en matière d'intermédiation financière. Si la banque a pu rationaliser la distribution de crédit et répondre aux contraintes de financement posées par la transition, elle a progressivement négligé sa vocation agricole initiale au profit d'une activité essentiellement commerciale. L'article met ainsi en évidence les conflits d'intérêts entre le monde agricole et celui du commerce. Il montre que cette situation conflictuelle a rendu d'autant plus délicate la gestion des problèmes monétaires rencontrés dans la période par cette économie mono-productrice.Banque coloniale; Transition post-esclavagiste; Crises de circulation; Banque de la Martinique

Knowledge, Hierarchy and incentives: Why human resource policy and trust matter

International audienceThis paper analyses the motivational dimension in the firm within different organizational set-up characterized by their levels of hierarchical pressures and two types of bonus rules Gausian and non Gaussian distribution perceived a more risky by the employees

Emission of photon echoes in a strongly scattering medium

We observe the two- and three-pulse photon echo emission from a scattering powder, obtained by grinding a Pr$^{3+}$:Y$_2$SiO$_5$ rare earth doped single crystal. We show that the collective emission is coherently constructed over several grains. A well defined atomic coherence can therefore be created between randomly placed particles. Observation of photon echo on powders as opposed to bulk materials opens the way to faster material development. More generally, time-domain resonant four-wave mixing offers an attractive approach to investigate coherent propagation in scattering media

Quadratic phase matching in slot waveguides

We analyze phase matching with reference to frequency doubling in nanosized quadratic waveguides encompassing form birefringence and supporting cross-polarized fundamental and second-harmonic modes. In an AlGaAs rod with an air void, we show that phase-matched second-harmonic generation could be achieved in a wide spectral range employing state-of-the-art nanotechnology.Comment: 3 pages, 4 figure

Experimental observation of second-harmonic generation and diffusion inside random media

We have experimentally measured the distribution of the second-harmonic intensity that is generated inside a highly-scattering slab of porous gallium phosphide. Two complementary techniques for determining the distribution are used. First, the spatial distribution of second-harmonic light intensity at the side of a cleaved slab has been recorded. Second, the total second-harmonic radiation at each side of the slab has been measured for several samples at various wavelengths. By combining these measurements with a diffusion model for second-harmonic generation that incorporates extrapolated boundary conditions, we present a consistent picture of the distribution of the second-harmonic intensity inside the slab. We find that the ratio $\ell_{2\omega}/L_c$ of the mean free path at the second-harmonic frequency to the coherence length, which was suggested by some earlier calculations, cannot describe the second-harmonic yield in our samples. For describing the total second-harmonic yield, our experiments show that the scattering parameter at the fundamental frequency \k_{1\omega}\ell_{1\omega} is the most relevant parameter in our type of samples.Comment: 10 pages, 7 figure

Mapping of periodically poled crystals via spontaneous parametric down-conversion

A new method for characterization of periodically poled crystals is developed based on spontaneous parametric down-conversion. The method is demonstrated on crystals of Y:LiNbO3, Mg:Y:LiNbO3 with non-uniform periodically poled structures, obtained directly under Czochralski growth procedure and designed for application of OPO in the mid infrared range. Infrared dispersion of refractive index, effective working periods and wavelengths of OPO were determined by special treatment of frequency-angular spectra of spontaneous parametric down-conversion in the visible range. Two-dimensional mapping via spontaneous parametric down-conversion is proposed for characterizing spatial distribution of bulk quasi-phase matching efficiency across the input window of a periodically poled sample.Comment: 19 pages, 6 figure

Analog Computing Simulations and the Production of Theoretical Evidence in Economic Dynamics

This article intends to bring wider attention to the implementation of the electro-analog simulation technique in economic dynamics during the 1950s and the early 1960s. The paper first discusses the main characteristics of the approach. Then, it focusses on some economic applications in the theory of spatially separated markets, inventory dynamics and Goodwin’s nonlinear accelerator business cycles model. Despite several consubstantial shortcomings, we argue that this approach contributed to the production of original theoretical evidence in economic dynamics before the generalization of the use of digital computers.Cet article s’intéresse à la mise en oeuvre de la technique de simulation électro-analogique pour modéliser la dynamique économique dans les années 50 et le début des années 60. Le texte examine d’abord les principales caractéristiques de l’approche. Il se concentre ensuite sur ses applications économiques relevant de la modélisation des marchés spatialement séparés, de la dynamique des stocks et des cycles d’affaire autour du modèle d’accélérateur non linéaire de Goodwin. Malgré plusieurs difficultés consubstantielles, l’article montre que cette approche a contribué à la production d’avancées théoriques originales avant la généralisation de l’utilisation des ordinateurs numériques

Clément Juglar et la théorie des cycles en France au premier XXe siècle : quelques éléments d’analyse

I. Introduction Avec la publication en 1862 de l’ouvrage de Clément Juglar, Des crises commerciales et de leur retour périodique, la France devint l’un des lieux de naissance du concept de cycle d’affaires. L’Académie des sciences morales et politiques avait en effet organisé l’année précédente un concours destiné à « rechercher les causes et signaler les effets des crises commerciales survenues en Europe et dans l’Amérique du Nord durant le cours du XIXe siècle ». Rapporté par Louis Wolowski..

Thermal effects in a single-frequency, fiber laser pumped, nested cavity optical parametric oscillator

International audienceWe investigate thermal effects in a nested-cavity doubly resonant optical parametric oscillator (NesCOPO), pumped by a high repetition rate laser, and the consequences on its spectral characteristics