1. A method of optimizing the performance of speech recognition and language understanding in a natural language processing system, comprising: compiling a first set of full names based on usage of the names during the course of a current spoken dialog session, wherein the first set of full names is stored in a dynamic database, wherein the dynamic database is sourced from data generated by a dialog manager unit in the natural language processing system and that receives input from a natural language understanding unit to interpret input representations in context; compiling a second set of full names based on presence in a pre-defined knowledge base that is built up from dialog sessions other than the current dialog session, wherein the second set of full names is stored in a static database, wherein the static database is sourced from data generated by a knowledge manager unit in the natural language processing system and that interfaces to one or more knowledge sources; deriving partial names for one or more of the names of the first set of full names and the second set of full names; combining the partial names and the first and second set of full names to generate a name model; assigning weight values to each of the names of the name model, wherein the relative weights depend on the usage of the names in the current dialog session and the presence in the pre-defined knowledge base, and wherein name entries in the dynamic database are weighted higher than name entries in the static database; and removing from an active vocabulary list those name entries with weight values below a defined minimum value to constrain name candidates processed by the natural language processing system.
7. The method of claim 1 wherein the partial names are derived by a process comprising at least one of pre-defining partial names based on the full names, learning the partial names through a knowledge-based system, applying a set of pre-defined rules to the full names to derive the partial names, and applying an n-gram model produced through statistical means.