A Non-parametric reassessment of target zone nonlinearities: The Spanish Peseta/Deutsche Mark exchange rate

In this paper we present evidence concerning the existence of target zone nonlinearities in the Spanish Peseta/Deutsche Mark exchange rate using data with daily frequency for the period 1989-1996. Using a non-parametric technique, the Alternation Conditional Expectations (ACE) algorithm, we obtain evidence of the existence of non-linearities in both exchange rate and interest rate differential, with a functional form close to the non-linear effects given by the target zone model with realignment risk.Target zones, exchange rate, realignment risk, ACE algorithm

Lineability, spaceability, and additivity cardinals for Darboux-like functions

We introduce the concept of maximal lineability cardinal number, mL(M), of a subset M of a topological vector space and study its relation to the cardinal numbers known as: additivity A(M), homogeneous lineability HL(M), and lineability L(M) of M. In particular, we will describe, in terms of L, the lineability and spaceability of the families of the following Darboux-like functions on R-n, n >= 1: extendable, Jones, and almost continuous function

Ab initio spectroscopic characterization of the radical CH3_3OCH2_2 at low temperatures

Spectroscopic and structural properties of methoxymethyl radical (CH$_3$OCH$_2$, RDME) are determined using explicitly correlated ab initio methods. This radical of astrophysical and atmospheric relevance has not been fully characterized at low temperatures, which has delayed the astrophysical searches. We provide rovibrational parameters, excitations to the low energy electronic states, torsional and inversion barriers and low vibrational energy levels. In the electronic ground state (X$^2$A), which appears "clean" from non-adiabatic effects, the minimum energy structure is an asymmetric geometry which rotational constants and dipole moment have been determined to be A$_0$=46718.6745 MHz, B$_0$=10748.4182 MHz, and C$_0$=9272.5105 MHz, and 1.432 D ($\mu_A$=0.6952 D, $\mu_B$=1.215 D, $\mu_C$=0.3016 D), respectively. A variational procedure has been applied to determine torsion-inversion energy levels. Each level splits into 3 subcomponents (A$_1$/A$_2$ and E) corresponding to the three methyl torsion minima. Although the potential energy surface presents 12 minima, at low temperatures, the infrared band shapes correspond to a surface with only three minima because the top of the inversion V$^{\alpha}$ barrier at ${\alpha}=0^{\circ}$ (109 cm$^{-1}$) stands below the zero point vibrational energy and the CH$_2$ torsional barrier is relatively high ($\sim$2000 cm$^{-1}$). The methyl torsion barrier was computed to be $\sim$500 cm$^{-1}$ and produces a splitting of 0.01 cm$^{-1}$ of the ground vibrational state

Funciones de densidad de los fundamentos y del tipo de cambio en una zona objetivo: evidencia empírica para el SME

En este artículo se analizan las funciones de densidad de los fundamentos y de las desviaciones del tipo de cambio bajo diferentes supuestos acerca del rumbo del proceso de los fundamentos y de las intervenciones monetarias que se efectúen. Una vez que se obtienen las funciones teóricas para los fundamentos, mediante un cambio de variable, podemos simular numéricamente las funciones de densidad para las desviaciones del tipo de cambio con objeto de comparadas con las empíricas. Los anteriores análisis de las distribuciones del tipo de cambio en el SME se han realizado usando el marco alemán como la moneda de referencia, asumiendo implícitamente la existencia de un sistema bilateral, cuando en realidad se trata de un sistema multilateral. Con objeto de solucionar este problema presentamos un método para calcular las distribuciones multilaterales de las desviaciones del tipo de cambio. La mayoría de las distribuciones que se obtienen presentan una baja frecuencia en el centro de la banda de fluctuación, algo que no es recogido en trabajos empíricos anteriores que rechazaban el modelo básico de zonas objetivo

Bounded and unbounded polynomials and multilinear forms: Characterizing continuity

In this paper we prove a characterization of continuity for polynomials on a normed space. Namely, we prove that a polynomial is continuous if and only if it maps compact sets into compact sets. We also provide a partial answer to the question as to whether a polynomial is continuous if and only if it transforms connected sets into connected sets. These results motivate the natural question as to how many non-continuous polynomials there are on an infinite dimensional normed space. A problem on the \emph{lineability} of the sets of non-continuous polynomials and multilinear mappings on infinite dimensional normed spaces is answered.Comment: 8 page

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Plain cigarette packs do not exert Pavlovian to instrumental transfer of control over tobacco-seeking

Journal ArticleResearch Support, Non-U.S. Gov'tCopyright © 2014 The Authors. Addiction published by John Wiley & Sons Ltd on behalf of Society for the Study of AddictionAIMS: To gain insight into the potential impact of plain tobacco packaging policy, two experiments were undertaken to test whether 'prototype' plain compared with branded UK cigarette pack stimuli would differentially elicit instrumental tobacco-seeking in a nominal Pavlovian to instrumental transfer (PIT) procedure. DESIGN, SETTING AND PARTICIPANTS: Two experiments were undertaken at the University of Bristol UK, with a convenience sample of adult smokers (experiment 1, n = 23, experiment 2, n = 121). MEASUREMENT: In both experiments, smokers were trained on a concurrent choice procedure in which two responses earned points for cigarettes and chocolate, respectively, before images of branded and plain packs were tested for capacity to elicit the tobacco-seeking response in extinction. The primary outcome was percentage choice of the tobacco- over the chocolate-seeking response in plain pack, branded pack and no-stimulus conditions. FINDINGS: Both experiments found that branded packs primed a greater percentage of tobacco-seeking (overall mean = 62%) than plain packs (overall mean = 53%) and the no-stimulus condition (overall mean = 52%; Ps ≤ 0.01, ŋp (2) s ≥ 0.16), and that there was no difference in percentage tobacco-seeking between plain packs and the no-stimulus condition (Ps ≥ 0.17, ŋp (2) s ≤ 0.04). Plain tobacco packs showed an overall 9% reduction in the priming of a tobacco choice response compared to branded tobacco packs. CONCLUSIONS: Plain packaging may reduce smoking in current smokers by degrading cue-elicited tobacco-seeking.British Heart FoundationCancer Research UKNIHRMRCESR

Caracterización de grietas de delaminación en laminados 0/90 simétricos

IV CONGRESO NACIONAL DE MATERIALES COMPUESTOS. Celebrado en Gijón, los días 21,22 y 23 de Noviembre de 2001La presencia en un laminado de láminas a 90° con respecto a la dirección preferente de la carga origina la aparición casi inmediata de grietas transversales (paralelas a las fibras) en la lámina a 90º,que alcanzan la interfase con la lámina vecina, presumiblemente a 0º. Esto puede originar la bifurcación de la grieta, que se propaga ahora en forma de delaminación entre las dos láminas. El objetivo de este estudio es el caracterizar el estado tensional en el fondo de la grieta de delaminación para diferentes longitudes de la misma. Ello es el primer paso para establecer los criterios de Mecánica de la Fractura que deben ser aplicados en la predicción de la aparición y propagación de este tipo de daño.The presence in a laminate of laminas oriented 90 degrees with respect to the preferent direction of load generates almost immediately the appearance in these laminas of cracks transversal to the load (parallel to the fibres in the lamina). These cracks reach the interface with the neighbour lamina, which is usually oriented 0 degrees. This can originate the bifurcation of the crack, which appears now propagating as a delamination crack between the two laminas. The objective of this study is to characterize the stress state at the tip crack of the delamination crack for different lengths of the crack. This is the first step to establish appropriate criteria based on Fracture Mechanics to predict the appearance and growth of this type of damage

Revisión de algoritmos para modelización de equilibrios de distribución de metales en procesos de extracción líquido-líquido

10 pages, 5 figures, 2 tables, 1 appendix.[EN] This work focuses on general guidelines to be considered for application of least-squares routines and artificial neural networks (ANN) in the estimation of metal distribution equilibria in liquid-liquid extraction process. The goal of the procedure in the statistical method is to find the values of the equilibrium constants (K¡) for the reactions involved in the metal extraction which minimizes the differences between experimental distribution coefficient (Dgxp) and theoretical distribution coefficients according to the mechanism proposed (Dt^^gor)- Iri the first part of the article, results obtained with the most frequently routine reported in the bibliography are compared with those obtained using the algorithms previously discussed. In the second part, the main features of a single back-propagation neural network for the same purpose are discussed, and the results obtained are compared with those obtained with the classical methods.[ES] El trabajo presenta las líneas generales a considerar para la estimación del equilibrio de distribución de metales en procesos de extracción líquido-líquido, según dos métodos: algoritmo clásico de mínimos cuadrados y redes neuronales artificiales. El objetivo del procedimiento, en el caso del método estadístico, es encontrar los valores de las constantes de equilibrio (KJ para las reacciones involucradas en la extracción del metal, que minimizan las diferencias entre el coeficiente de distribución experimental y el coeficiente de distribución teórico, de acuerdo al mecanismo propuesto. En la primera parte del artículo se comparan los resultados obtenidos a partir de los algoritmos usados más habitualmente en la bibliografía, con los datos obtenidos mediante el algoritmo previamente descrito. En la segunda parte, se presentan las características fundamentales para aplicar una red neuronal sencilla con algoritmo hack-propagatioriy y los resultados obtenidos se comparan con los de los métodos clásicos.Peer reviewe