Which string method can I use to make sure that the phrase ‘invalid response’ only displays if the user has typed something other than ‘yes’ or ‘no’, without paying attention to their capitalization?

Abstract: The large-scale integration of renewable energy introduces significant uncertainty challenges to the optimal dispatch of power systems. To fully account for the impact of the randomness in ...

Abstract: The growing demand for electric power and the need for an energy transition that contributes to the reduction of global greenhouse gas emissions have driven the development of various energy ...