If heave motion in the platform causes horizontal parametric vibration of a Compliant Vertical Access Riser (CVAR). the riser may become unstable. A combination of riser parameters lies in the unstable region aggravates vibrational damage to the riser. Change of axial tensile stress in the riser combined with its natural frequency and mode shape change results in mode coupling. https://herbsdailyes.shop/product-category/eye-health/