1. A human-machine dialogue system having a plurality of computer-implemented dialogue components comprising: a user client for delivering output prompts to a human user and receiving dialogue inputs from the human user including speech inputs; an automatic speech recognition (ASR) engine in communication with the user client for processing the speech inputs to determine corresponding sequences of representative text words; a natural language understanding (NLU) engine in communication with the ASR engine for processing the text words to determine corresponding NLU-ranked semantic interpretations; a semantic re-ranking module in communication with the NLU engine for re-ranking the NLU-ranked semantic interpretations based on at least one of dialogue context information and world knowledge information; and a dialogue manager in communication with the user client and the semantic re-ranking module for responding to the re-ranked semantic interpretations and generating the output prompts so as to manage a dialogue process with the human user.