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Electromechanical Catastrophe

A transducer is a system that couples two loads. For example, an electromechanical transducer couples a mechanical force and an electrical voltage. A two-load, nonlinear system can exhibit rich behavior of bifurcation, which can be displayed in a three-dimensional space, with the horizontal plane representing the two loads, and the vertical axis representing the state of the system. In this three-dimensional space, a state of equilibrium at fixed loads corresponds to a point on a surface.

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Electro-mechanical coupling bifurcation and bulging propagation in a cylindrical dielectric elastomer tube

This paper explores the critical and post-bulging bifurcation of a cylindrical dielectric elastomer (DE) tube undergoing finite deformation under electro-mechanical coupling loading. Explicit expressions for the critical conditions of electro-mechanical bifurcation are derived by using a simplified mathematical method. The post-bifurcation path is comprehensively investigated by specifying the material model as ideal dielectric elastomer.

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Charge localization instability in a highly deformable dielectric elastomer

A highly deformable capacitor made of a soft dielectric and two conformal

electrodes can switch between two states discontinuously, by a first-order transition, as the total

charge varies gradually. When the total charge is small, it spreads evenly over the area of the

capacitor, and the capacitor deforms homogeneously. When the total charge is large, it localizes in

a small region of the capacitor, and this region thins down preferentially. The capacitor will

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Bulge test at nano-scale: The surface effects

Bulge test is an effective technique to measure the mechanical properties of thin films. As the membrane size decreases to nano-scale, the surface effect plays a significant role in determining the mechanical behavior of the membrane, and the techniques commonly used to measure the bulk materials properties are not applicable. We explore the surface effect on the nano-scale bulge test using combined continuum theories and atomistic simulations. We formulate the load-deflection relation by incorporating the surface effect and analyze its size-dependent behavior. The present theoretical model is in quantitative agreement with the molecular dynamics simulations.

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Postdoctoral position in the theory of materials

Postdoctoral position in the theory of materials

Materials Department
University of California, Santa Barbara

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The surface effect on the strain energy release rate of buckling delamination in thin film–substrate systems

Gurtin–Murdoch continuum surface elasticity model is employed to study the buckling
delamination of ultra thin film–substrate system. The effects of surface deformation and
residual stress on the large deflection of ultra thin film are considered in analysis. A
concept of effective bending rigidity (EBR) for ultra thin plate is proposed on the basis of
Gurtin–Murdoch continuum theory and the principle of minimum potential energy. The
governing equations with EBR are formally consistent with the classical plate theory,

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