Journal: Microsystems & Nanoengineering

Article Title: Coulomb-actuated microbeams revisited: experimental and numerical modal decomposition of the saddle-node bifurcation

doi: 10.1038/s41378-021-00265-y

Figure Lengend Snippet: a Solution without stress stiffening, calculated using two different methods, 2D FEM and the collocation method. Neglecting stress stiffening results in strong disagreement with the results presented by Gilbert et al. b Static deflection curves with stress stiffening. The inclusion of stress stiffening leads to good agreement with Gilbert et al. c Static deflection curves calculated using 3D FEM including stress stiffening and nonlinear contact. Pull-in and pull-out voltages match the Gilbert et al. results .

Article Snippet: For the 2D FEM model, the nonlinear geometric effects are activated in ANSYS accordingly.

Techniques:

Journal: Microsystems & Nanoengineering

Article Title: Coulomb-actuated microbeams revisited: experimental and numerical modal decomposition of the saddle-node bifurcation

doi: 10.1038/s41378-021-00265-y

Figure Lengend Snippet: a Static voltage–deflection curves of a Coulomb-actuated microbeam for a range of beam thicknesses t calculated with 2D FEM. The drive voltage is normalized by the pull-in voltage v PI , and deflection is normalized by the electrostatic gap g . Solid lines indicate the stable branches, and dashed lines indicate the unstable branches. b–e Modal contribution extracted from 2D FEM results according to Eq. for the zeroth, second, fourth, and sixth modes, respectively. f–i Modal contributions b 0 , b 2 , b 4 , and b 6 for the two limiting cases calculated with the FEM (blue and red markers). The v → 0 and w (0) → 1 limits (contact singularity) are analytically modeled with Euler-Bernoulli beam theory (red solid line). This limit is the concentrated load case. It is strongly affected by stress stiffening. The limits v → 0 and w (0) → 0 are analytically modeled with Timoshenko beam theory (blue solid line). This limit is the constant (distributed) load case. In this limit, stress stiffening does not contribute at all. The dotted lines, shown for reference, are the predictions of Euler-Bernoulli beam theory when stress-stiffening and Timoshenko effects are omitted.

Article Snippet: For the 2D FEM model, the nonlinear geometric effects are activated in ANSYS accordingly.

Techniques:

Journal: The Scientific World Journal

Article Title: Exploratory Study on the Methodology of Fast Imaging of Unilateral Stroke Lesions by Electrical Impedance Asymmetry in Human Heads

doi: 10.1155/2014/534012

Figure Lengend Snippet: CT image and 2D finite element model of human head used for simulation experiments. (a) A head CT image of a healthy volunteer was used to construct a finite element model. (b) A finite element model (FEM) with an ideally symmetrical structure was constructed according to the right boundary of each layer of head tissues in the head CT image. The 2D head model consisted of 17659 triangular elements, 9200 nodes, and 16 electrodes (A: anterior; P: posterior; L: left; and R: right).

Article Snippet: According to finite element modeling [ ], a 2D human head finite element model (FEM) with ideally bilateral symmetry was established with COMSOL Multiphysics 3.5a (COMSOL, Inc., Stockholm, Sweden) ( ).

Techniques: Construct

Journal: The Scientific World Journal

Article Title: Exploratory Study on the Methodology of Fast Imaging of Unilateral Stroke Lesions by Electrical Impedance Asymmetry in Human Heads

doi: 10.1155/2014/534012

Figure Lengend Snippet: Index of asymmetry (IA) of the 2D FEM of human head.

Article Snippet: According to finite element modeling [ ], a 2D human head finite element model (FEM) with ideally bilateral symmetry was established with COMSOL Multiphysics 3.5a (COMSOL, Inc., Stockholm, Sweden) ( ).

Techniques: