Vibration Analysis of Piezoelectric Composite Plate Resting on Nonlinear Elastic Foundations Using Sinc and Discrete Singular Convolution Differential Quadrature Techniques

Table 2

Comparison between the normalized fundamental frequencies using the sinc DQM, grid size N, and the previous exact and numerical frequencies for the simply supported square isotropic plate (a/h = 5, , , , and ).

Results	Normalized frequencies
	N
Sinc DQM	3	55.9218		103.4553	124.1464	161.3903	177.5293	186.4058
	5	55.9721		103.5484	124.2581	161.5355	177.6891	186.5736
	7	56.0369		103.6682	124.2982	161.5391	177.6930	186.5777
	9	56.0369		103.6683	124.2982	161.5391	177.6930	186.5777
	11	56.0369		103.6683	124.2982	161.5391	177.6930	186.5777
Analytical [68]		56.0359		—	—	—	—	—
RHSDT [69]		56.0310		—	—	—	—	—
NSDT [60]		56.0311		—	—	—	—	—
Execution time (sec)		5.615225 over N = 7 × 5 × 5

RHSDT: refined hyperbolic shear deformation theory; NSDT: new shear deformation theory; DQM: differential quadrature method.