Abstract: A heating system includes first and second heating devices, a temperature sensor, a first controller and a second controller. The first and second heating devices are respectively arranged above a crucible and around the crucible for heating semiconductor material in the crucible. The temperature sensor is configured to detect the temperature of the first heating device and to generate a temperature signal. The first controller is configured to control operation of the first heating device so as to adjust the temperature thereof based on the temperature signal. The second controller is coupled to the second heating device and is configured to control operation of the second heating device so as to adjust the temperature thereof, based on an external control signal.

Abstract: A digital language teaching system is disclosed, in which through an audio control manner, the learner, by utilizing a learning sub-machine, can focus on listening and speaking practice under a simple hardware control and operation, so that the teaching staff and the learner can have a more direct and faster interaction for improving learning efficiency. Moreover, through the output devices of the video device and teaching providing the learner the teaching image and the interactive teaching pictures, the video learning manner can be provided to the learner through the supplemental multimedia teaching materials, so that the teaching staff can teach the learners in accordance with their aptitudes, and the learner can find the most suitable learning method.