20. The electronic device of claim 15 , wherein the keyword setting unit is further configured to combine the keyword model with at least one other keyword model associated with a second particular target keyword to form a combined keyword model, wherein the second particular target keyword is associated with at least one other function of the electronic device.
20. The electronic device of claim 15 , wherein the keyword setting unit is further configured to combine the keyword model with at least one other keyword model associated with a second particular target keyword to form a combined keyword model, wherein the second particular target keyword is associated with at least one other function of the electronic device. 21. The electronic device of claim 20 , further comprising: a sound sensor configured to receive the input sound; a keyword detection unit configured to detect whether keywords are included in the input sound based on the combined keyword model; and a function management unit configured to: activate the function in response to detection of the particular target keyword in the input sound based on the combined keyword model; and activate the at least one other function in response to detection of the second particular target keyword in the input sound based on the combined keyword model.