89 citations · 140 across the 9 of their papers we have counts for
9 papers
Well-posed continuum equations for granular flow with compressibility and -rheology
T. Barker, D. G. Schaeffer, M. Shearer +1
Continuum modelling of granular flow has been plagued with the issue of ill-posed equations for a long time. Equations for incompressible, two-dimensional flow based on the Coulomb…
The hanging thin rod: A singularly perturbed eigenvalue problem
Yossi Farjoun, David G. Schaeffer
We study the vibrations of a hanging thin flexible rod, in which the dominant restoring force in most of the domain is tension due to the weight of the rod, while bending elasticit…
Cardiac Alternans Arising from an Unfolded Border-Collision Bifurcation
Xiaopeng Zhao, David G. Schaeffer, Carolyn M. Berger +2
Following an electrical stimulus, the transmembrane voltage of cardiac tissue rises rapidly and remains at a constant value before returning to the resting value, a phenomenon know…
Alternate Pacing of Border-Collision Period-Doubling Bifurcations
Xiaopeng Zhao, David G. Schaeffer
Unlike classical bifurcations, border-collision bifurcations occur when, for example, a fixed point of a continuous, piecewise map crosses a boundary in state spa…
Small-Signal Amplification of Period-Doubling Bifurcations in Smooth Iterated Maps
Xiaopeng Zhao, David G. Schaeffer, Carolyn M. Berger +1
Various authors have shown that, near the onset of a period-doubling bifurcation, small perturbations in the control parameter may result in much larger disturbances in the respons…
Evidence for an unfolded border-collision bifurcation in paced cardiac tissue
Carolyn M. Berger, Xiaopeng Zhao, David G. Schaeffer +3
We investigate, both experimentally and theoretically, the bifurcation to alternans in heart tissue. Previously, this phenomenon has been modeled either as a smooth or as border-co…