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                                                 Resonant Micromechanical Systems

                                                             Resonant Micromechanical Systems  231









                                   1.04                                      0.1
                              rω I- II
                                b
                                       1
                                       1 1
                                                                           c w


                                                  c l              0.01
                                                                5 5
                              Figure 5.3 Bending resonant frequency ratio:  model  I  predictions against model II
                              predictions (paddle microcantilever of constant thickness).








                                     10
                                                                              0.1
                                I- III
                              rω b

                                      0.
                                       1
                                      0.1
                                                                            c w
                                                  c l              0.01
                                                                 1 1
                              Figure 5.4 Bending resonant frequency ratio: model I predictions against model III
                              predictions (paddle microcantilever of constant thickness).

                                where the superscripts I, II, and III indicate models I, II, and III, respectively.
                                The bending resonant frequencies corresponding to models I and II are given
                                in Eqs. (5.3) and (5.8), whereas the bending resonant frequency according to
                                model III is formulated in Eq. (3.33). Figures 5.3 and 5.4 are three-dimen-
                                sional plots of the ratios defined in Eqs. (5.11).
                                  The following nondimensional parameters were used to draw Figs. 5.3 and
                                5.4:







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