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81.
82.
Federica Camin Ron Wehrens Daniela Bertoldi Luana Bontempo Luca Ziller Matteo Perini Giorgio Nicolini Marco Nocetti Roberto Larcher 《Analytica chimica acta》2012
In compliance with the European law (EC No. 510/2006), geographical indications and designations of origin for agricultural products and foodstuffs must be protected against mislabelling. This is particularly important for PDO hard cheeses, as Parmigiano Reggiano, that can cost up to the double of the no-PDO competitors. 相似文献
83.
Irwin M. Chaiken Yechiel Shai Giorgio Fassina Paolo Caliceti 《Macromolecular Symposia》1988,17(1):269-279
Analytical high performance liquid affinity chromatography (analytical HPLAC) has been investigated as an experimental guide to both synthetic design and affinity technological use of peptide and protein recognition surfaces. This work has progressed from the ongoing use of analytical affinity chromatography to study interaction mechanisms of naturally-occurring peptides and proteins, including enzyme fragment complexes and neuroendocrine biosynthetic precursors. We recently initiated a study to use analytical HPLAC for de novo design of recognition peptides called “anti-sense peptides”. Present data suggest the potential to use anti-sense peptides as “synthetic antibodies”, in immobilized forms, for biomolecular separation and analysis. Analogous studies have been started with immobilized natural antibodies in analytical immuno HPLAC. Our present data typify the growing usefulness of analytical HPLAC when designing recognition molecules, analyzing their interaction characteristics, and devising ways to use them in affinity technology. 相似文献
84.
In this paper, we perform an analytical and numerical study of the extreme values of specific observables of dynamical systems possessing an invariant singular measure. Such observables are expressed as functions of the distance of the orbit of initial conditions with respect to a given point of the attractor. Using the block maxima approach, we show that the extremes are distributed according to the generalised extreme value distribution, where the parameters can be written as functions of the information dimension of the attractor. The numerical analysis is performed on a few low dimensional maps. For the Cantor ternary set and the Sierpinskij triangle, which can be constructed as iterated function systems, the inferred parameters show a very good agreement with the theoretical values. For strange attractors like those corresponding to the Lozi and He?non maps, a slower convergence to the generalised extreme value distribution is observed. Nevertheless, the results are in good statistical agreement with the theoretical estimates. It is apparent that the analysis of extremes allows for capturing fundamental information of the geometrical structure of the attractor of the underlying dynamical system, the basic reason being that the chosen observables act as magnifying glass in the neighborhood of the point from which the distance is computed. 相似文献
85.
Daniela Meloni Alcide di Sarra Giorgio Fiocco 《Journal of Quantitative Spectroscopy & Radiative Transfer》2005,93(4):397-413
The vertical profile of Saharan dust in the atmosphere is generally characterized by a large aerosol concentration in the mid troposphere, differently from the climatological distribution of other types of particles, that show a peak at the surface and a rapid decrease with height. Saharan dust is also characterized by particles of relatively large size of irregular shape, and variable values of the single scattering albedo (the ratio between radiation scattering and extinction). The dust's peculiar vertical distribution is expected to produce an effect on the calculation of the direct aerosol radiative forcing at the surface and at the top of the atmosphere. This effect is investigated by comparing estimates of aerosol direct visible radiative forcing at the surface and at the top of the atmosphere for dust vertical profiles measured in the Mediterranean, and for the climatological profile. The radiative forcing is estimated by means of an accurate radiative transfer model, and for the ocean surface. The sensitivity of the results on the solar zenith angle, aerosol optical depth, and aerosol absorption is also investigated. The aerosol radiative forcing at the surface shows a very small dependency on the aerosol vertical profile. At the top of the atmosphere, the radiative forcing is weakly dependent on the vertical profile (up to 10% variation on the daily average forcing) for low absorbing particles; conversely, it shows a strong dependency (the daily radiative forcing may vary up to 100%) for absorbing particles. The top of the atmosphere visible radiative forcing efficiency produced by dust having single scattering albedo <0.7 is higher by 4 W m−2 when the observed vertical profile instead of the standard profile is used in the calculations (i.e. it produces a lower cooling). For values of the single scattering albedo around 0.67, the sign of the forcing depends on the vertical profile. The influence of the vertical distribution on the radiative forcing is largest at small values of the solar zenith angle, and at short wavelengths. 相似文献
86.
The Fourier transform of orthogonal polynomials with respect to their own orthogonality measure defines the family of Fourier–Bessel
functions. We study the asymptotic behaviour of these functions and of their products, for large real values of the argument.
By employing a Mellin analysis we construct a general framework to exhibit the relation of the asymptotic decay laws to certain
dimensions of the orthogonality measure, that are defined via the divergence abscissas of suitable integrals. The unifying
r?le of Mellin transform techniques in deriving classical and new results is underlined.
Submitted: November 5, 2004. Accepted: January 6, 2006. 相似文献
87.
We consider an extension of the set union problem, in which dynamic weighted backtracking over sequences of unions is permitted. We present a new data structure which can support each operation inO(logn) time in the worst case. We prove that this bound is tight for pointer based algorithms. Furthermore, we design a different data structure to achieve better amortized bounds. The space complexity of both our data structures isO(n). Motivations for studying this problem arise in logic programming memory management.Work partially supported by NSF Grant CCR-88-14977, by the ESPRIT II Basic Research Actions Program of the EC under contract No. 3075 (Project ALCOM), and by the Italian MURST Project Algoritmi e Strutture di Calcolo.Partially supported by an IBM Graduate Fellowship. 相似文献
88.
This paper considers packing problems with balancing conditions and items consisting of clusters of parallelepipeds (mutually orthogonal, i.e. tetris-like items). This issue is quite frequent in space engineering and a real-world application deals with the Automated Transfer Vehicle project (funded by the European Space Agency), at present under development. A Mixed Integer Programming (MIP) approach is proposed. The three-dimensional single bin packing problem is considered. It consists of orthogonally placing, with possibility of rotation, the maximum number of parallelepipeds into a given parallelepiped. A MIP formulation of the problem is reported together with a MIP-based heuristic approach. Balancing conditions are furthermore examined, as well as the orthogonal placement (with rotation) of tetris-like items into a rectangular domain.Received: September 2003, Revised: February 2004, AMS classification:
90B99, 05B40, 90C90, 90C59Thanks are due to T. A. Ciriani for the important suggestions given for the whole paper and to S. Gliozzi (IBM, Business Consulting Services) for the significant support offered, in particular in discussing the topics presented in Sect. 2.1. 相似文献
89.
Giorgio Donati Nicola Durante Alessandro Siciliano 《Designs, Codes and Cryptography》2014,72(1):135-139
The linear collineation group of a classical unital of $\mathrm{PG}(2,q^2)$ contains a group of homologies of order $q+1$ . In this paper we prove that if $\mathcal{U }$ is a unital of PG $(2,q^2)$ stabilized by a homology group of order $q+1$ and $q$ is a prime number, then $\mathcal{U }$ is classical. 相似文献
90.