Table 4 surface pattern based qa system qa system descriptionshovy et al 34 learning surface text patterns for qa system implemented an automatic learning environment soubbtin et al 35 pattern of potential answer expression as clues to the right answerszhang et al 36 web base pattern mining and matching approach to question answering greenwood et al 37 using name entity tagger to . Question answering application has been applied in various fields to solve problems related to the teams developed chemistry question answering systems based upon their knowledge . Stuck on a puzzling chemistry problem studycom has answers to your toughest chemistry homework questions with detailed step by step explanations cant locate your question in our library go . Building a question answering system from scratch part 1 famous with all the big companies trying to jump up at the leaderboard and using advanced techniques like attention based rnn models to get the best accuracy all the github repositories that i found related to squad by other people have also used rnns. If you are building a question answering system and use nlp engine like rasa nlu dialogflow luis this nlp engine can answer predefined questions however if there is no predefined intent you can call this automatic qna system to search in documents and return the answer