LMC-SMP83 is a planetary nebula in the Large Magellanic Cloud whose central star is recently reported by Pena et al. to show decreases in temperature and luminosity of at least 50% over a time span of seven years. Serendipitously, this object is observed with the Planetary and Faint Object Cameras onboard the Hubble Space Telescope between 1991

EL TRABAJO RECOGIDO EN LA PRESENTE MEMORIA SE BASA EN OBSERVACIONES REALIZADAS CON EL FOTOMETRO LOI-T INSTALADO EN EL OBSERVATORIO DEL TEIDE. SE ESTABLECE UN PROCEDIMIENTO PARA EL ANALISIS DE LOS DATOS, CALCULO DE LOS FILTROS OPTIMOS PARA LA IDENTIFICACION DE LOS MODOS, MEDIDA DE FRECUENCIAS, ANCHURAS, AMPLITUDES Y DESDOBLAMIENTO ROTACIONAL. EN SU

EL TRABAJO DESARROLLADO EN LA PRESENTE TESIS DOCTORAL CONSISTE EN EL DISEÑO Y FABRICACION DE UN ESTABILIZADOR DE IMAGENES BIDIMENSIONALES OPTIMIZADO PARA IMAGENES SOLARES DE VARIADA MORFOLOGIA, INCLUYENDO LAS DE BAJO CONTRASTE. EL SISTEMA PERMITE IGUALMENTE REALIZAR OTRO TIPO DE TAREAS TALES COMO EL SEGUIMIENTO DE ESTRUCTURAS DURANTE LARGOS

We present early-time infrared (IR) and optical spectroscopy, and optical photometry, of the Type Ia supernova 1994D. These observations provide the most complete optical-IR spectral coverage ever achieved for a Type Ia at this phase. Optical and IR spectra were obtained as early as 9d before maximum light. The combined optical and IR spectra of SN

In this paper we propose a new method to prevent the saturation of any set of hidden units of a multilayer neural network. This method is implemented by adding a regularization term to the standard quadratic error function, which is based on a repulsive action between pairs of patterns.

This is a study of the UV variability of the galaxy Fairall-9 between 1978 and 1991. Table 1 shows the UV continuum fluxes measured in three "line-free" windows centered at 1171, 1400 and 1910 A (observed wavelengths), and corrected for E(B-V)=0.035 extinction. The IUE Fine Error Sensor (FES) counts (optical photometry) are also given in this table