There are two important goals to do research on language-extinction problem with computer simulation. One is to describe the process of language getting extinct from the earth in auxiliary; the other is to in auxiliary describe the endangered state before language extinction and make early-warning. At present, there are many researchers focusing on the research on language-extinction problem with computer simulation with different purposes. But what researchers want to achieve tends not to be the same. The research work about the second purpose is less than others. When we take the second purpose in our consideration, it's natural to combine the linguists' definition of language endangered state with computer simulation. It's difficult for us to determine the language's endangered state relying only on a static standard. That is also the main reason why the existing language extinction simulation model can't be compatible with the simulation of the early-warning of endangered state before language extinction. Based on the views of academics in the field of linguistics, this paper gave dynamic assumptions of language endangered state in three different aspects--the proportion of losing mother-tongue population, the proportion of mother-tongue speakers' age range and the ability to use language. Then, we designed the dynamic characteristics of the early-warning simulation model of endangered state before the language-extinction with multi-agent. And we dispatched the mentioned computer simulation model in a discrete event simulation manner. The work on computer simulation did in this paper confirms the subjective viewpoint of endangered language definition in the field of linguistics and reveals the significance of language evolution simulation modeling in the efforts made in rescuing the endangered language

How to protect the endangered languages is a typical and important social problem around the world. Now, the existing social computational models of language evolution are generally short of language endangerment warning and language recovery. These two parts are very important for language evolution. In this paper, an artificial society is cultivated based on multi-agents with purpose of observing language endangerment and its recovery phenomenon. In view of endangerment factor of population language, resilience inner protective factor and resilience composite protective factor, corresponding social computational model is given. From experimental results we can see that the computational model draws the endangerment trend of the weaker one in the language competition and the recovery process of weaker endangered language under the effect of resilience composite protective factor. To break through research bottleneck for high cost of language endangerment experiment in real society, the proposed computational model is working in an artificial society. The introduction of artificial society plays an important and practical role in the design and evaluation of endangered language protection scheme.Keywords: Language competition, endangered language protection, agents, social computing, artificial society.According to data provided by Ethnologue, authoritative publication journal gathering language information all over the world, there are 7202 known languages in the world [1]. Based on the prediction admitted by most scholars, more than half of these languages will disappear after a century. Language is very important for the heritage and spread of human culture. Each language contains the quintessence of one country or one nation, so language extinction means culture extinction. Known this, it's not surprising that language endangerment and extinction has become a worldwide social problem.Based on MAT (Multi-Agents Technology), a social computational model for language endangerment and recovery is proposed in this paper. The computational model draws the endangerment trend and the recovery process under the effect of "resilience protection factor" of the weaker one in language competition in the artificial society. This paper is structured as follows. Related research work is introduced in Section 1 and boundary of language endangerment status is presented. Social computational model on language endangerment and recovery and related computational experiments to prove the validity of the model are given in Section 2. The paper is concluded in Section 3. ANALYSIS OF RELATED WORK AND DEFINI-TION OF LANGUAGE ENDANGERMENT STATUSLanguage endangerment is a typical social problem. Now, it has attracted much attention from many linguists in many countries. But there is a difficulty we can't solve in traditional social science research. Language endangerment is the fact we can't avoid in history and culture. Like other traditional social science problem, it's impossible to conduct computational experiments that c...