We obtain inequalities for the weighted approximation error of Baskakov type operators and their derivatives. Such inequalities
are valid for functions of polynomial growth and are expressed in terms of weighted moduli of continuity.
IfA is a σ-algebra on setX, thenl0∞(X,A) is a barrelled space of class χ0. IfA is an algebra, there are conditions which imply thatl0∞(X,A) is suprabarelled. Here, wheneverA is an algebra, we give conditions forl0∞(X,A) to be not barrelled which are related with the existence of non-trivial convergent sequences.
A conjecture by Agronsky and Ceder , stating that a continuum is an orbit enclosing ω-limit set of a continuous map from
the k-dimensional cube Ik into itself if and only if it is arcwise connected, is disproved in both directions. Our main result is a general theorem
allowing a construction of orbit enclosing ω-limit sets for triangular maps.
We study classes of relative injective and projective comodules and extend well-known results about projective comodules given
in . The existence of covers and envelopes by these classes of comodules is also studied and used to characterize the projective
dimension of a coalgebra. We also compare this homological coalgebra with the very intensively studied homological algebra
of the dual algebra (see ).
Authors:P. López-de-Alba, L. López-Martínez, and J. Amador-Hernández
Two multivariate calibration methods, partial least squares types 1 and 2 (PLS-1 and PLS-2) have been applied to the simultaneous determination of U(VI) and Th(IV) ions as complexes with carminic acid by visible absorption spectrophotometry. The results obtained by application of different chemometric approaches are discussed. No significant advantages were found between the methods. The proposed methods were applied satisfactorily to the determination of these ions in synthetic solutions simulating sulfuric acid leach solutions obtained from uranium-thorium ores.
Authors:L. López-Martínez, J. Guzmán-Mar, and P. López-de-Alba
A bivariate calibration method, has been applied to the simultaneous determination of U(VI) and Th(IV) ions as complexes with carminic acid by visible absorption spectrophotometry. The bivariate calibration method was applied satisfactorily to the determination of these ions in synthetic solutions simulating sulfuric acid leach solution obtained from uranium-thorium ores and the results were compared with those given by first derivative spectrophotometry. No significant advantages of any method were found.
We are immersed in a knowledge society that calls for indicators to go beyond economic factors to measure the development of a country. In this paper we use an adapted microeconomic model that determines the value of a country’s intellectual capital. For this, we consider intangibles such as human development, economic structure, international trade, foreign image and innovation. This measurement of intellectual capital is divided into human and structural capital and is used to analyse the relationship between these capitals and the economic development of the 27 countries in the European Union (EU27). The results show that when we consider aspects other than economic variables, the differences between countries are larger. Moreover, there is an inverse relationship between the management of intangibles and economic growth, which is why the former progresses after the latter have occurred.