Solitary waves in the Nonlinear Dirac Equation

In the present work, we consider the existence, stability, and dynamics of solitary waves in the nonlinear Dirac equation. We start by introducing the Soler model of self-interacting spinors, and discuss its localized waveforms in one, two, and three spatial dimensions and the equations they satisfy. We present the associated explicit solutions in one dimension and numerically obtain their analogues in higher dimensions. The stability is subsequently discussed from a theoretical perspective and then complemented with numerical computations. Finally, the dynamics of the solutions is explored and compared to its non-relativistic analogue, which is the nonlinear Schr{\"o}dinger equation. A few special topics are also explored, including the discrete variant of the nonlinear Dirac equation and its solitary wave properties, as well as the PT-symmetric variant of the model

Warehousing complex data from the Web

∗ Corresponding authors Abstract: The data warehousing and OLAP technologies are now moving onto handling complex data that mostly originate from the Web. However, intagrating such data into a decision-support process requires their representation under a form processable by OLAP and/or data mining techniques. We present in this paper a complex data warehousing methodology that exploits XML as a pivot language. Our approach includes the integration of complex data in an ODS, under the form of XML documents; their dimensional modeling and storage in an XML data warehouse; and their analysis with combined OLAP and data mining techniques. We also address the crucial issue of performance in XML warehouses

Precise measurement of the angular correlation parameter aβν in the β decay of 35^{35}Ar with LPCTrap

Expérience GANIL/SPIRALInternational audienc

A hybrid cuckoo search algorithm for cost optimization of mechanically stabilized earth walls

Having a wide range of applications in civil engineering practice, Mechanically Stabilized Earth Walls (MSEWs) are regarded as efficient and reliable alternatives to the conventional retaining structure types. As is often the case in engineering, the performance and cost-effectiveness of these structures rely on robust design strategies, which must be proficient to yield optimal solutions in multimodal spaces. While the inherent characteristics of engineering problems often render the design a challenging task, metaheuristic algorithms are suitable options provided that problem-specific considerations and modifications are implemented. In this regard, Cuckoo Search (CS) and its variants are successful in many engineering applications. In the present study, CS is adopted to optimize the reinforcement type, length, and layout of MSEWs and a hybrid CS (HCSDE) variant based on Differential Evolution formulation is developed to further enhance the search capability of the algorithm. The proposed algorithm is applied to various MSEW design benchmarks and comparatively evaluated with respect to well-established methods such as Genetic Algorithm and Particle Swarm Optimization. The results of the study indicate that CS is competent for the problem and the capability of the algorithm can be further enhanced through the proposed adaptations in HCSDE. The improved solutions of HCSDE compared to the other optimization methods highlight the proposed formulation as a promising algorithm for practical implementations