Which approach to speech recognition avoids the problem caused by the variation in speech patterns among different speakers?

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A.M. turing developed a technique for determining whether a computer could or could not demonstrate the artificial Intelligence,, Presently, this technique is called

A series of AI systems developed by Pat Langley to explore the role of heuristics in scientific discovery.

A network with named nodes and labeled arcs that can be used to represent certain natural language grammars to facilitate parsing.