690 research outputs found

    Rule Extraction by Genetic Programming with Clustered Terminal Symbols

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    When Genetic Programming (GP) is applied to rule extraction from databases, the attributes of the data are often used for the terminal symbols. However, in the case of the database with a large number of attributes, the search space becomes vast because the size of the terminal set increases. As a result, the search performance declines. For improving the search performance, we propose new methods for dealing with the large-scale terminal set. In the methods, the terminal symbols are clustered based on the similarities of the attributes. In the beginning of search, by reducing the number of terminal symbols, the rough and rapid search is performed. In the latter stage of search, by using the original attributes for terminal symbols, the local search is performed. By comparison with the conventional GP, the proposed methods showed the faster evolutional speed and extracted more accurate classification rules

    Tuning of the height of energy barrier between locally-excited and charge transfer states by altering the fusing position of <i>o</i>-carborane in phenylnaphthalene

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    We synthesized two types of the regioisomers fused by a phenylnaphthalene ring with variable connection points to the o-carborane scaffold. In this paper, we describe their photoluminescence (PL) properties and detailed photochemical mechanisms. According to the series of optical measurements, interestingly, they showed different PL characters in terms of wavelength and the dual-emission character despite that they have the common aromatic unit. Variable-temperature PL measurements and quantum chemical calculations suggested that the substitution position of aryl groups to o-carborane plays an important role in determining the energy barrier to the intramolecular charge-transfer (ICT) state at the S1 state. Finally, it is revealed that the relative position of the C–C bond of o-carborane and the aryl center should be responsible for the photophysical events of aryl-o-carboranes

    Effect of Soft Abdomen on Quadrupedal Gait Control

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    The 11th International Symposium on Adaptive Motion of Animals and Machines. Kobe University, Japan. 2023-06-06/09. Adaptive Motion of Animals and Machines Organizing Committee.Poster Session P5

    A unified origin for the 3D magnetism and superconductivity in Nax_xCoO2_2

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    We analyze the origin of the three dimensional (3D) magnetism observed in nonhydrated Na-rich Nax_xCoO2_2 within an itinerant spin picture using a 3D Hubbard model. The origin is identified as the 3D nesting between the inner and outer portions of the Fermi surface, which arise due to the local minimum structure of the a1ga_{1g} band at the Γ\Gamma-A line. The calculated spin wave dispersion strikingly resembles the neutron scattering result. We argue that this 3D magnetism and the spin fluctuations responsible for superconductivity in the hydrated systems share essentially the same origin.Comment: 5pages, 6figure
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