An Integration nonlocal coupling () integrates an expression over the source (some selected geometric entities like domains, boundaries, or edges). You can also use it with a point as the source to make the value of an expression at that point available globally. The integral is evaluated by integrating the expression (integrand) in the argument over the source (or, in some cases, by summing the expression over the node points in the source). Integration coupling operators have global destination, so they can be evaluated anywhere in the model. Because it is an operator, you can define one integration operator (intop1, for example) for a part of the geometry (a boundary, for example) and then use that several times in the model to compute integrals over that boundary for different integrands. For example, intop1(T) is the integral of the temperature T over the boundary, and intop1(1) is simply the length (2D) or area (3D) of the boundary. Also, using the dest operator it is possible to create convolution integrals. The default Operator name is intop1.