2,088 research outputs found
Wide Localized Solitons in Systems with Time and Space-Modulated Nonlinearities
In this work we apply point canonical transformations to solve some classes
of nonautonomous nonlinear Schr\"{o}dinger equation namely, those which possess
specific cubic and quintic - time and space dependent - nonlinearities. In this
way we generalize some procedures recently published which resort to an ansatz
to the wavefunction and recover a time and space independent nonlinear equation
which can be solved explicitly. The method applied here allow us to find wide
localized (in space) soliton solutions to the nonautonomous nonlinear
Schr\"{o}dinger equation, which were not presented before. We also generalize
the external potential which traps the system and the nonlinearities terms.Comment: 19 pages, 5 figure
Effect of heuristics on serendipity in path-based storytelling with linked data
Path-based storytelling with Linked Data on the Web provides users the ability to discover concepts in an entertaining and educational way. Given a query context, many state-of-the-art pathfinding approaches aim at telling a story that coincides with the user's expectations by investigating paths over Linked Data on the Web. By taking into account serendipity in storytelling, we aim at improving and tailoring existing approaches towards better fitting user expectations so that users are able to discover interesting knowledge without feeling unsure or even lost in the story facts. To this end, we propose to optimize the link estimation between - and the selection of facts in a story by increasing the consistency and relevancy of links between facts through additional domain delineation and refinement steps. In order to address multiple aspects of serendipity, we propose and investigate combinations of weights and heuristics in paths forming the essential building blocks for each story. Our experimental findings with stories based on DBpedia indicate the improvements when applying the optimized algorithm
Synthesis of a Ruthenium-tetra(tht)dichloride Compound and the Molecular Structure of the Partially Oxidized Compound RuCl\u3csub\u3e2\u3c/sub\u3e(tht)\u3csub\u3e2.2\u3c/sub\u3e(tht-O)\u3csub\u3e1.8\u3c/sub\u3e
Interaction-induced chaos in a two-electron quantum-dot system
A quasi-one-dimensional quantum dot containing two interacting electrons is
analyzed in search of signatures of chaos. The two-electron energy spectrum is
obtained by diagonalization of the Hamiltonian including the exact Coulomb
interaction. We find that the level-spacing fluctuations follow closely a
Wigner-Dyson distribution, which indicates the emergence of quantum signatures
of chaos due to the Coulomb interaction in an otherwise non-chaotic system. In
general, the Poincar\'e maps of a classical analog of this quantum mechanical
problem can exhibit a mixed classical dynamics. However, for the range of
energies involved in the present system, the dynamics is strongly chaotic,
aside from small regular regions. The system we study models a realistic
semiconductor nanostructure, with electronic parameters typical of gallium
arsenide.Comment: 4 pages, 3ps figure
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