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Fukui, Japan

The Fukui University of Technology is a private university founded in 1950 and located in Fukui city, Fukui Prefecture, Japan. Wikipedia.

Hioki Z.,Tokushima University | Ohkuma K.,Fukui University of Technology
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics | Year: 2012

Possible non-standard top-quark interactions with the gluon and the W boson induced by SU(3) × SU(2) × U(1) gauge-invariant dimension-6 effective operators are studied for hadron-collider experiments. Current limits on top-gluon couplings are presented by using the latest experimental data of tt productions at the Tevatron and the Large Hadron Collider (LHC). The optimal-observable procedure is applied to the charged-lepton distributions in pp→ttX→ℓ+X' (ℓ = e or μ) at the LHC in order to estimate the expected statistical uncertainties in measurements of those non-standard top-gluon and top-. W couplings that contribute to this process in the leading order. © 2012 Elsevier B.V. Source

Yamanishi T.,Fukui University of Technology | Liu J.-Q.,Japan National Institute of Information and Communications Technology | Nishimura H.,University of Hyogo
International Journal of Neural Systems | Year: 2012

Recently, numerous attempts have been made to understand the dynamic behavior of complex brain systems using neural network models. The fluctuations in blood-oxygen-level-dependent (BOLD) brain signals at less than 0.1 Hz have been observed by functional magnetic resonance imaging (fMRI) for subjects in a resting state. This phenomenon is referred to as a "default-mode brain network." In this study, we model the default-mode brain network by functionally connecting neural communities composed of spiking neurons in a complex network. Through computational simulations of the model, including transmission delays and complex connectivity, the network dynamics of the neural system and its behavior are discussed. The results show that the power spectrum of the modeled fluctuations in the neuron firing patterns is consistent with the default-mode brain network's BOLD signals when transmission delays, a characteristic property of the brain, have finite values in a given range. © 2012 World Scientific Publishing Company. Source

Hioki Z.,Tokushima University | Ohkuma K.,Fukui University of Technology
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2013

Constraints on the nonstandard top-gluon couplings composed of the chromomagnetic- and chromoelectric-dipole moments of the top quark are updated by combining the latest data of top-pair productions from the Tevatron, 7-TeV LHC, and 8-TeV LHC. We find that adding the recent 8-TeV data to the analysis is effective to get a stronger constraint on the chromoelectric-dipole moment than the one from the Tevatron and 7-TeV LHC alone. We also discuss how those constraints on the nonstandard couplings could be further improved when the 14-TeV LHC results become available in the near future. © 2013 American Physical Society. Source

Takaki T.,Kyoto Institute of Technology | Tomita Y.,Fukui University of Technology
International Journal of Mechanical Sciences | Year: 2010

We have developed a numerical model of recrystallization taking the inhomogeneities of the plastic deformation of a polycrystalline metal into account. Here, the plastic deformation of the polycrystalline metal is simulated by the finite element method based on crystal plasticity theory and the microstructure evolution during recrystallization is simulated by the multi-phase-field method. In primary recrystallization simulations, nucleation is the most difficult problem. In the present model, the deformation microstructure is predicted from the results of a crystal plasticity finite element simulation, and spontaneous nucleation is achieved through abnormal grain growth that is enabled by introducing the misorientation dependences of grain boundary energy and mobility. As a result of simulations under three different compression strains, it is confirmed that primary recrystallization simulations depending on the amount of deformation and taking the inhomogeneities of the plastic deformation of a polycrystalline metal into consideration can be successfully performed by employing the proposed model. © 2009 Elsevier Ltd. All rights reserved. Source

Takaki T.,Kyoto Institute of Technology | Yoshimoto C.,Kyoto Institute of Technology | Yamanaka A.,Tokyo University of Agriculture and Technology | Tomita Y.,Fukui University of Technology
International Journal of Plasticity | Year: 2014

Dynamic recrystallization (DRX) occurs during the hot-working of a metallic material with low-to-medium stacking-fault energy. The macroscopic mechanical behavior during hot-working is largely affected by the microstructure evolution due to DRX. In this study, a novel multiscale hot-working model was developed by coupling the multi-phase-field dynamic recrystallization (MPF-DRX) model and large deformation elastic-plastic finite element (FE) method using J2 flow theory to evaluate the microstructure evolution and macroscopic mechanical behavior, respectively. We call this model the multi-phase-field and finite element dynamic recrystallization (MPFFE-DRX) model. Compression simulations with nonuniform deformation of a cylinder confirmed that the newly developed MPFFE-DRX model can be used to evaluate the macroscopic mechanical behavior during hot-working by considering the DRX microstructure evolution, which differs depending on the area. We also confirmed that the MPFFE-DRX model can be used to simulate macroscopic mechanical behavior depending on the initial microstructure by varying the initial grain size. © 2013 Elsevier Ltd. All rights reserved. Source

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