In common teaching environment, a lot of teaching information is transmitted by the means of speech. Because of the deaf students'difficulties in accepting aural information, how to make aural information transform to visual information that can be accepted by deaf students becomes an important issue. Traditional methods include sign language, lip reading, notes taking and so on. Speech recognition technology is a technique that can changes speech into text with the development of computer. Because this technique, which changes aural information into visual information, meets the needs of the teaching for deaf students, it has been used in classroom teaching for deaf students for over 30 years abroad and in China it has been started to be used.In order to know the effect of this technique in the teaching for deaf students, researchers in foreign countries have studied on it for more than twenty years. They interviewed with teachers and students and knew their attitudes and opinions on this technique and its effect. Beside that, they experimented on this subject and got how this technique affected students'study. In China, this research has not started. The author thinks that the essence of instruction aims at promoting the skills and qualities of the students through information transmission. The application of speech recognition technology basically solves the problem of information transmission in teaching for deaf students. So the author's discussion on the effect of this technique will focus on information transmission.The author measures the information transmission in class according to the following aspects: Shannon's information transmission model and the definition of information quantity, features of information transmission in classroom teaching, information entropy, information quality, the quantity of character, students'memory, information understanding, etc. Information entropy is an objective measurement for information transmission in class and can be calculated by Shannon's formula. Information quality is a subjective measurement for information transmission in class. And the related materials can be obtained by inquiry with teachers and students. The quantity of character objectively describes the total quantity of information transmission according to the features of this research and can be calculated directly. The students'memory and information understanding are used to measure the information students get and the related materials can be obtained by students'doing exercise. In the process of research, the author experimented upon 28 deaf students and interviewed two teachers who used speech recognition technique and analyzed field research notes on the application of speech recognition technology.All obtained data, facts and related comprehensive analysis show that the application of speech recognition technology can increase the quantity of information transmitted by teachers in class, improve the students'understanding of the information get in class, make the information more understandable, integrated, and sequential, and transmit more abstract information. However, this research also shows that there are many factors which influence the effect of speech recognition. The factors include teaching contents, teachers'familiarity of teaching contents, teaching methods besides speech recognition technique, the quality of teacher's voice, text format, accuracy of text information, environmental noise, students'language understanding ability, attitude towards learning and so on.Because of the limitation in sample, time and teaching experience, further research is needed to explore the effect of speech recognition technology in information transmission in class. |