Stubborn Learning

The paper studies a specific reinforcement learning rule in two-player games when each player faces a unidimensional strategy set. The essential feature of the rule is that a player keeps on incrementing her strategy in the same direction if and only if her utility increases. The paper concentrates on games on the square [0; 1] x [0; 1] with bilinear payoff functions such as the mixed extensions of 2 x 2 games. It studies the behavior of the system in the interior as well as on the borders of the strategy space. It precisely exhibits the trajectories of the system and the asymptotic states for symmetric, zero-sum, and twin games.

The partition bundle of type A_{N-1} (2, 0) theory

Six-dimensional (2, 0) theory can be defined on a large class of six-manifolds endowed with some additional topological and geometric data (i.e. an orientation, a spin structure, a conformal structure, and an R-symmetry bundle with connection). We discuss the nature of the object that generalizes the partition function of a more conventional quantum theory. This object takes its values in a certain complex vector space, which fits together into the total space of a complex vector bundle (the `partition bundle') as the data on the six-manifold is varied in its infinite-dimensional parameter space. In this context, an important role is played by the middle-dimensional intermediate Jacobian of the six-manifold endowed with some additional data (i.e. a symplectic structure, a quadratic form, and a complex structure). We define a certain hermitian vector bundle over this finite-dimensional parameter space. The partition bundle is then given by the pullback of the latter bundle by the map from the parameter space related to the six-manifold to the parameter space related to the intermediate Jacobian.Comment: 15 pages. Minor changes, added reference

Une ville qui bouge, une ville qui change. Métropolisation et redistribution de la population dans l’agglomération de Mexico

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L’offre de travail dans le modèle CANDIDE : un commentaire

The paper is a brief critical evaluation of the treatment of the "supply of labour" in the CANDIDE model. The authors note that the "supply of labour block" does not occur to have retained much of the effort of the CANDIDE developing team. With regards to the specification of the equation of supply of labour, no attempts have been made to integrate new developments in labour economics (a better treatment of the secondary workers supply of labour, a Fisherian utility maximising approach). We note certain econometric difficulties which have not been overcome: The limited dependant variable problem, the lag structure problem…Finally, though it is encouraging to see attempts in macro-economic models to integrate explicitly a labour demand and supply block with a certain disagregation, important economic problems in the labour market can be dealt only with much more flexible and disagregated models than CANDIDE

NEW APPROACHES OF THE FORECAST OF THE AGEING OF PLASMA JET NOZZLE IN INDUSTRIAL SETTINGS OF THERMAL SPRAYING

p.19The optimization of the extension of the lifetime of the torches without hazard of drop of the product is an unceasing industrial difficulty. It needs a reliable criterion to characterize the wear, and thus indicate when the nozzle used should be switched by a new nozzle. These criteria are still quite subjective and hold the operator's experience. In 2003, David RIGOT, in collaboration with the Volvo Aero Corporation, has defined a number of criteria in his thesis dissertation [ ]. This study led to the realization of an electronic module alert detecting the hazardous time of process. The focus method was based on research and tracking characteristic frequencies in arc voltage fluctuations and in acoustic noise that is the image. It seems that a rough statistical study of signals is able to help define and visualize simple criteria ruthless variation is usable in objective phenomena wear alert. This is ad hoc measures for smooth power spectrum [ ] [ ] and its variability. Filtered signal is used to distinguish typically one or two epochs of slow wear followed by an epoch of fast wear. This difference is clear after a suitable choice of used frequency bands. Graphical representations are very expressive; they are supplemented by statistical tests. Signals & method: results, by David RIGOT on campaign made shots in September 2003 at the aircraft manufacturer Volvo Aero. Files led to collect a series of measures standardized on the time life of the nozzles. For one, whose use was particularly long, a few shots "vacuum" were prosecuted beyond of the usual threshold used in order to study the ageing. Sound torch and tension thus collected at various times of operation nozzles, with several frequencies of sampling, feed and no feed of powder. They allow first approach directly extract global statistical parameters which it represents dissimilarity based on time: moments, skewness, kurtosis, entropy [ ]. To each power spectra measurement, time is calculated from each signal multiple sampling. Each of the frequencies spectra is smooth inside of a convolution window by a kernel assessor [ ]. A simultaneous representation of the power of signals and their erraticism are used to visually choose the most discriminating frequency bands. Two sets of settings are then assessed: mean and variance of spectrum in the band selected; global parameters newly evaluated from filtered in the chosen band signals. Results: most selective statistics evolve in a similar manner and allows periods wear, while the overall results are most often efficient. For example templates to slope failure (piecewise linear models) are used. The spectra of tension frequencies and the spectra of sound frequencies give similar results. The sound is usable with the feed or without feed of powder. Sequential simple tests may be expected to assess the time of rapid wear

Stubborn Learning

The paper studies a specific reinforcement learning rule in two-player games when each player faces a unidimensional strategy set. The essential feature of the rule is that a player keeps on incrementing her strategy in the same direction if and only if her utility increases. The paper concentrates on games on the square [0; 1] x [0; 1] with bilinear payoff functions such as the mixed extensions of 2 x 2 games. It studies the behavior of the system in the interior as well as on the borders of the strategy space. It precisely exhibits the trajectories of the system and the asymptotic states for symmetric, zero-sum, and twin games

The genus Alucita in North America, with description of two new species (Lepidoptera: Alucitidae)

The North American fauna of Alucitidae is shown to include three widespread species: Alucita montana Barnes et Lindsey, 1921 (nec Cockerell), Alucita adriendenisi sp. nov. (type locality: Manitoulin Island, Ontario, Canada), and Alucita lalannei sp. nov. (type locality: Maynooth, Ontario, Canada). Alucita hexadactyla (L., 1758) and A. huebneri Wallengren, 1862 do not occur in North America. The three North American species are described and illustrated. Alucita montana is found from southwestern Quebec and Vermont, west to British Columbia, and south to Arizona, California, and Texas; its caterpillar is associated with Symphoricarpos spp. (Caprifoliaceae). Alucita adriendenisi is known from northwestern Quebec and New York, west to Alberta and the Northwest Territories, with more southern populations (isolated?) in West Virginia, Arizona, and Texas; its caterpillar feeds on flowers of Lonicera dioica L. (Caprifoliaceae) in Michigan. Alucita lalannei has been found in Ontario, Manitoba, and Alberta, Canada; its host plant is unknow