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H Kokame

Publications and source records attributed to H Kokame.

4 recordsLinked to original sources
PubMed2000

Delayed-feedback control of spatial bifurcations and chaos in open-flow models

A delayed-feedback control scheme is presented for suppressing spatial bifurcation and chaotic behavior in open-flow models. It is shown that spatial bifurcation and chaotic behavior never occur when the delayed-feedback controller is designed such that the following two conditions are satisfied: all the poles of the transfer function of each site are inside a unit circle and the H(infinity) norm of the transfer function is less than 1. We provide a simple systematic procedure for design of the delayed-feedback controller. It is confirmed that our theoretical results agree well with the numerical simulations.

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PubMed2000

Spatiotemporal stability of one-way open coupled nonlinear systems

The present paper investigates the spatiotemporal stability of homogeneous solutions in one-way open coupled nonlinear systems. We show that the H(infinity) norm concept, which has been used as an important index in the field of robust control theory, allows us to grasp the mechanism of spatial instability in coupled systems. Spatial instability occurs only when the H(infinity) norm of the transfer function of each site is greater than 1. It is shown that numerical simulations for one-way open coupled double scroll circuits are in good agreement with our theoretical results.

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PubMed1999

Coupled map car-following model and its delayed-feedback control.

This paper proposes a coupled map car-following traffic model, which describes a dynamical behavior of a group of road vehicles running in a single lane without overtaking. This model consists of a lead vehicle and following vehicles, which have a piecewise linear optimal velocity function. When the lead-vehicle speed is varied, we can observe a traffic jam in the group of the vehicles. We derive a condition under which the traffic jam never occurs in our model. Furthermore, in order to suppress the traffic jam, for each vehicle we use a dynamic version of decentralized delayed-feedback control proposed in [Konishi, Hirai, and Kokame, Phys. Rev. E 58, 3055 (1998)], and provide a systematic procedure for designing the controller.

Journal Article↗