A multivariate polynomial P (x1, . . . , xn) with real coefficients is said to be absolutely positive from a real number B iff it and all of its non-zero partial derivatives of every order are positive for x1, . . . , xn ≥ B. We also call such B a bound for the absolute positiveness of P . The main goal of this paper is to devise a “nice” formula for computing a bound of a given polynomial. The...

A previous study showed that the initial ocular following responses elicited by sudden motion of a large random-dot pattern were only modestly attenuated when that whole pattern was shifted out of the plane of fixation by altering its horizontal binocular disparity, but the same disparity applied to a restricted region of the dots had a much more powerful effect [Vision Research 41 (2001) 3371]...

An absolute flux calibrated reference spectrum of Vega, the primary calibration standard in the optical, is presented. The spectrum covers the entire 0.12 to 2.6 microns wavelength. The ultraviolet spectrum is based on IUE measurements. The optical and near-infrared up to 1.05 microns consists of Hayes (1985) average spectrum. A model spectrum normalized to Hayes (1985) Johnson V flux covers th...

A continuous-wave cavity ring-down spectrometer has been built for precise determination of absolute frequencies of Doppler-broadened absorption lines. Using a thermo-stabilized Fabry-Pérot interferometer and Rb frequency references at the 780 nm and 795 nm, 0.1 - 0.6 MHz absolute frequency accuracy has been achieved in the 775-800 nm region. A water absorption line at 12579 cm(-1) is studied t...

The first order absolute moment provides a ridge map similar to the one provided by the GoG (gradient of Gaussian) filter. However, unlike the GoG filter, the first order absolute moment provides ridges at both edges and lines and gives rise to local extrema of the ridges at line endings, corners and junctions. Furthermore, a class of filters is obtained by introducing three low-pass filters at...

In this study, different derivative spectrophotometric methods are proposed for the simultaneous determination of chlorpheniramine maleate (CP), phenylephrine HCl (PE) and phenylpropanolamine HCl (PP) in their ternary mixtures and in pharmaceutical dosage forms. Spectra of single component and ternary mixtures of various concentrations and combinations from zero- to fourth-derivation were obtai...

In this study, different derivative spectrophotometric methods are proposed for the simultaneous determination of chlorpheniramine maleate (CP), phenylephrine HCl (PE) and phenylpropanolamine HCl (PP) in their ternary mixtures and in pharmaceutical dosage forms. Spectra of single component and ternary mixtures of various concentrations and combinations from zero- to fourth-derivation were obtai...

We consider a multicriteria lexicographic Boolean problem of minimizing absolute deviations of linear functions from zero. We investigate the stability radius which can be understood as a limit level of independent perturbations of the parameters, for which new lexicographic optima do not appear. Lower and upper accessible bounds of the stability radius are obtained.