11,124 research outputs found
Solvable Leibniz Algebras with Filiform Nilradical
In this paper we continue the description of solvable Leibniz algebras whose nilradical
is a filiform algebra. In fact, solvable Leibniz algebras whose nilradical is a naturally graded filiform
Leibniz algebra are described in [6] and [8]. Here we extend the description to solvable Leibniz algebras
whose nilradical is a filiform algebra. We establish that solvable Leibniz algebras with filiform Lie
nilradical are Lie algebras.Ministerio de Economía y Competitividad MTM2013-43687-
Influence of oxygen pressure on the fs laserinduced oxidation of molybdenum thin films
We present a study of femtosecond (1028 nm, 230 fs, 54.7 MHz) laser processing on molybdenum (Mo) thin films. Irradiations were done under ambient air as well as pure oxygen (O2) at various gauge pressures (4, 8, 12 and 16 psi). Our results indicate that the high heating rates associated with laser processing allow the production of different molybdenum oxides. Raman spectroscopy and scanning electron microscopy are used to characterize the molybdenum oxidation for the different irradiation and oxygen pressures parameters chosen showing a high correlation between well-defined oxidation zones and the oxygen pressure surrounding the samples during the irradiation of the Mo thin films
Rapidly reconfigurable slow-light system based on off-resonant Raman absorption
We present a slow-light system based on dual Raman absorption resonances in warm rubidium vapor. Each
Raman absorption resonance is produced by a control beam in an off-resonant Λ system. This system combines
all optical control of the Raman absorption and the low-dispersion broadening properties of the double Lorentzian absorption slow light. The bandwidth, group delay, and central frequency of the slow-light system can all be tuned dynamically by changing the properties of the control beam. We demonstrate multiple pulse delays with
low distortion and show that such a system has fast switching dynamics and thus fast reconfiguration rates
Solvable Leibniz algebras with NFn⊕ F1m nilradical
All finite-dimensional solvable Leibniz algebras L, having N = NFn⊕ F1m as the nilradical and the dimension of L equal to n+m+3 (the maximal dimension) are described. NFn and F1m are the null-filiform and naturally graded filiform Leibniz algebras of dimensions n and m, respectively. Moreover, we show that these algebras are rigid
Man's capability for self-locomotion on the moon. Phase 2 - Bungee simulator evaluation
Design and performance of suspension system for lunar gravity simulatio
From Collapse to Freezing in Random Heteropolymers
We consider a two-letter self-avoiding (square) lattice heteropolymer model
of N_H (out ofN) attracting sites. At zero temperature, permanent links are
formed leading to collapse structures for any fraction rho_H=N_H/N. The average
chain size scales as R = N^{1/d}F(rho_H) (d is space dimension). As rho_H -->
0, F(rho_H) ~ rho_H^z with z={1/d-nu}=-1/4 for d=2. Moreover, for 0 < rho_H <
1, entropy approaches zero as N --> infty (being finite for a homopolymer). An
abrupt decrease in entropy occurs at the phase boundary between the swollen (R
~ N^nu) and collapsed region. Scaling arguments predict different regimes
depending on the ensemble of crosslinks. Some implications to the protein
folding problem are discussed.Comment: 4 pages, Revtex, figs upon request. New interpretation and emphasis.
Submitted to Europhys.Let
About Designing an Observer Pattern-Based Architecture for a Multi-objective Metaheuristic Optimization Framework
Multi-objective optimization with metaheuristics is an active and popular research field which is supported by the availability of
software frameworks providing algorithms, benchmark problems, quality indicators and other related components. Most of these tools follow a monolithic architecture that frequently leads to a lack of flexibility when a user intends to add new features to the included algorithms. In this paper, we explore a different approach by designing a component-based architecture for a multi-objective optimization framework based on the observer pattern. In this architecture, most of the algorithmic components
are observable entities that naturally allows to register a number of observers. This way, a metaheuristic is composed of a set of observable and observer elements, which can be easily extended without requiring to modify the algorithm. We have developed a prototype of this architecture and implemented the NSGA-II evolutionary algorithm on top of it as a case study. Our analysis confirms the improvement of flexibility using this architecture, pointing out the requirements it imposes and how performance is affected when adopting it.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech
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