Normally unmanned installation Normally unmanned installation A Normally Unmanned Installation (NUI) is a type of automated offshore Oil/Gas platform designed to be primarily operated remotely, without the constant presence of personnel. These generally were characterized by their small size, often consisting of just a well bay with a helipad on top. They are often a compromise of providing the convenience of surface wellheads, which are easier to build and maintain, while avoiding the high operating costs of a full production platform. They are generally only used in shallower water, where constructing many small NUIs is a relatively easy and cheap option as compared
Normally hyperbolic invariant manifold the unstable bundle and denoted "E" and "E", respectively. With respect to some Riemannian metric on "M", the restriction of "Df" to "E" must be a contraction and the restriction of "Df" to "E" must be an expansion, and must be relatively neutral on formula_4. Thus, there exist constants formula_5 and "c" > 0 such that and Normally hyperbolic invariant manifold A normally hyperbolic invariant manifold (NHIM) is a natural generalization of a hyperbolic fixed point and a hyperbolic set. The difference can be described heuristically as follows: For a manifold formula_1 to be normally hyperbolic we are allowed to