Their problem was that both the membrane current l M and the membrane potential V M are also changing constantly during the action potential. Now if one of these variables could be held constant during the action potential (i.e., V M), measurement of l M would enable them to calculate g M at any instant.
The CMMi Easy button notes on Product Integration (PI) Process Area Product Integration (PI) is one of the core Engineering Process Areas within CMMi, this process is concerned with assembly of product components to build the finished software product.
In calculus, the process of calculating an integral. Integration is the inverse of differentiation, since integrating a given function results in a function whose derivative is the given function. Integration is used in the calculation of such things as the areas and volumes of irregular shapes and solids.