“…NURBS functions have been widely used because of their flexibility and computational efficiency, in several areas, such as computer graphics, FEM for solid/fluid mechanics and high-order differential equations, shape optimization, and time integration schemes (for instance, [26][27][28][29][30]). In order to define the element concept in the context of IsoGeometric analysis, geometry, velocities, displacements, and displacement variations must be discretized with the following expressions:…”