2,279 research outputs found
Dressed Quark Propagator at Finite Temperature in the Schwinger-Dyson approach with the Rainbow Approximation - exact numerical solutions and their physical implication
The Schwinger-Dyson equation for the quark in the rainbow approximation at
finite temperature (T) is solved numerically without introducing any ansatz for
the dressed quark propagator. The dymanical quark mass-function and the
wave-function renormalization are found to have non-trivial dependence on
three-momentum, Matsubara-frequency and temperature. The critical temperature
of the chiral phase transition (T_c) and the T-dependence of the quark
condensate are highly affected by the wave-function renormalization. We found
that T_c \simeq 155 MeV which is consistent with the result of the finite
temperature lattice QCD simulation. It is also found that the system is not a
gas of free quarks but a highly interacting system of quarks and gluons even in
the chirally symmetric phase.Comment: 13 pages, 8 figures, LaTe
Spatial Period-Doubling Agglomeration of a Core-Periphery Model with a System of Cities
The orientation and progress of spatial agglomeration for Krugman's core--periphery model are investigated in this paper. Possible agglomeration patterns for a system of cities spread uniformly on a circle are set forth theoretically. For example, a possible and most likely course predicted for eight cities is a gradual and successive one---concentration into four cities and then into two cities en route to a single city. The existence of this course is ensured by numerical simulation for the model. Such gradual and successive agglomeration, which is called spatial-period doubling, presents a sharp contrast with the agglomeration of two cities, for which spontaneous concentration to a single city is observed in models of various kinds. It exercises caution about the adequacy of the two cities as a platform of the spatial agglomerations and demonstrates the need of the study on a system of cities
Spatial Period-Doubling Agglomeration of a Core-Periphery Model with a System of Cities
The orientation and progress of spatial agglomeration for Krugman's core--periphery model are investigated in this paper. Possible agglomeration patterns for a system of cities spread uniformly on a circle are set forth theoretically. For example, a possible and most likely course predicted for eight cities is a gradual and successive one---concentration into four cities and then into two cities en route to a single city. The existence of this course is ensured by numerical simulation for the model. Such gradual and successive agglomeration, which is called spatial-period doubling, presents a sharp contrast with the agglomeration of two cities, for which spontaneous concentration to a single city is observed in models of various kinds. It exercises caution about the adequacy of the two cities as a platform of the spatial agglomerations and demonstrates the need of the study on a system of cities.Agglomeration of population; Bifurcation; Core-periphery model; Group theory; Spatial period doubling
Modular DFR: Digital Delayed Feedback Reservoir Model for Enhancing Design Flexibility
A delayed feedback reservoir (DFR) is a type of reservoir computing system
well-suited for hardware implementations owing to its simple structure. Most
existing DFR implementations use analog circuits that require both
digital-to-analog and analog-to-digital converters for interfacing. However,
digital DFRs emulate analog nonlinear components in the digital domain,
resulting in a lack of design flexibility and higher power consumption. In this
paper, we propose a novel modular DFR model that is suitable for fully digital
implementations. The proposed model reduces the number of hyperparameters and
allows flexibility in the selection of the nonlinear function, which improves
the accuracy while reducing the power consumption. We further present two DFR
realizations with different nonlinear functions, achieving 10x power reduction
and 5.3x throughput improvement while maintaining equal or better accuracy.Comment: 20 pages, 11 figures. Accepted for publication in the International
Conference on Compilers, Architectures, and Synthesis for Embedded Systems
(CASES) 2023. Will appear in ACM Transactions on Embedded Computing Systems
(TECS
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