Search results for "Characterization"
showing 10 items of 1054 documents
(p,q)-summing sequences
2002
Abstract A sequence (x j ) in a Banach space X is (p,q) -summing if for any weakly q -summable sequence (x j ∗ ) in the dual space we get a p -summable sequence of scalars (x j ∗ (x j )) . We consider the spaces formed by these sequences, relating them to the theory of (p,q) -summing operators. We give a characterization of the case p=1 in terms of integral operators, and show how these spaces are relevant for a general question on Banach spaces and their duals, in connection with Grothendieck theorem.
Superposition in Classes of Ultradifferentiable Functions
2006
We present a complete characterization of the classes of ultradifferentiable functions that are holomorphically closed. Moreover, we show that any class holomorphically closed is also closed under composition (now without restrictions on the number of variables). In this case, we also discuss continuity and differentiability properties of the non-linear superposition operator g → f ◦ g.
Graph languages defined by systems of forbidden structures: A survey
1988
This paper deals with different ways of defining graph languages. These are the so-called forbidden structures. Some results on decision problems, their complexity, and set theoretic closure properties are scetched. A normal form, the minimal systems, are given. Finally the influence of the different kinds of forbidden structures on the descriptive power of the systems is shown.
Completeness number of families of subsets of convergence spaces
2016
International audience; Compactoid and compact families generalize both convergent filters and compact sets. This concept turned out to be useful in various quests, like Scott topologies, triquotient maps and extensions of the Choquet active boundary theorem.The completeness number of a family in a convergence space is the least cardinality of collections of covers for which the family becomes complete. 0-completeness amounts to compactness, finite completeness to relative local compactness and countable completeness to Čech completeness. Countably conditional countable completeness amounts to pseudocompleteness of Oxtoby. Conversely, each completeness class of families can be represented a…
Liquid-Phase Chemistry of Superheavy Elements
2013
An overview over the chemical separation and characterization experiments of the four transactinide elements so far studied in liquid phases, rutherfordium (Rf), dubnium (Db), seaborgium (Sg), and hassium (Hs), is presented. Results are discussed in view of the position of these elements in the Periodic Table and of their relation to theoretical predictions. Short introductions on experimental techniques in liquid-phase chemistry, specifically automated rapid chemical separation systems, are also given. Studies of nuclear properties of transactinide nuclei by chemical isolation will be mentioned. Some perspectives for further liquid-phase chemistry on heavier elements are briefly discussed.
Electro-optical characterization of ruthenium-based dye sensitized solar cells: A study of light soaking, ageing and temperature effects
2017
Abstract In this work, we report on the electro-optical characterization of Dye Sensitized Solar Cells (DSSCs) which use ruthenium complexes as sensitizers. In particular, several kinds of measurements have been performed to study the electrical performances and the efficiency levels of the cells at different operating conditions. In detail, the measurements have been conducted at varying temperatures and hours of light soaking. Our results show that the short circuit current density J SC , the open circuit voltage V OC and the conversion efficiency η increase with the hours of light soaking, while they decrease with temperature. A thorough investigation on the light soaking process at the …
One diode circuital model of light soaking phenomena in Dye-Sensitized Solar Cells
2018
Abstract In this work, we report on the modelling of light soaking effect on Ruthenium-based Dye Sensitized Solar cells (DSSCs). Such a phenomenon can be detected when exposing the cells at increasing hours of illumination and produces a reversible performance increase. Starting from the results obtained through the electro-optical characterization of the cells, we applied a one-diode circuital-model. Our results show a good agreement between the experimental and the simulated data, with a mean square error in the order of 10−12 and a maximum error in current lower than 0.6%. Finally such results allowed us to infer some precise trends followed by the cells main electrical parameters and of…
Experimental Characterization of a Double Receiver Dynamic Wireless Charging System
2020
The aim of this work is the characterization of a dynamic wireless charging system low power prototype and the validation of a simplified mathematical model of the employed double D coils. The difference between a single receiver and a dual receiver system is also shown, highlighting how the last one can significantly reduce the costs of the charging infrastructure.
Editorial for the Proceedings of the 2016 E-MRS Spring Meeting Symposium T - Advanced Materials and Characterization Techniques for Solar Cells III
2016
Abstract This paper contains the editorial of the proceedings of the 2016 E-MRS spring meeting symposium T on “Advanced materials and characterization techniques for solar cells III”.
The measurement of rank mobility
2009
Abstract In this paper we investigate the problem of measuring social mobility when the social status of individuals is given by their rank. In order to sensibly represent the rank mobility of subgroups within a given society, we address the problem in terms of partial permutation matrices which include standard (“global”) matrices as a special case. We first provide a characterization of a partial ordering on partial matrices which, in the standard case of global matrices, coincides with the well-known “concordance” ordering. We then provide a characterization of an index of rank mobility based on partial matrices and show that, in the standard case of comparing global matrices, it is equi…