A Ph.D. dissertation at the College of Education for Girls at the University of Kufa discussed the use of integral transform for solving partial differential equations and its applications.

The dissertation presented by student Rehab Ali Khudair aims to find new double transforms named Double ZZ transforms and Complex ZZ transforms as useful tools distinguished by speed and accuracy to obtain solutions for hydrodynamic pressure, load-bearing, and heat equation describing particle movement in a viscoelastic fluid.

The dissertation concluded that using Double ZZ transform as a powerful tool for solving motion and continuity equations in hydrodynamic lubrication and compressive lubrication and for solving the heat equation describing particle movement in a viscoelastic fluid, and using Complex Double ZZ transform to estimate stress peaks in the knee joint for daily activities.

The dissertation recommended that the Double ZZ transform and Compound Double ZZ transform can be developed to solve a system of ordinary differential equations and solve partial differential equations with variable coefficients.