Abstract: In the collaboration practice among industry, universities and research institutes, universities and enterprises can influence the amount of knowledge of both sides by changing the knowledge transfer input to resolve the problem of income among industry, universities and research institutes. Universities' knowledge output and enterprises' absorptive amount can be affected at time, natural growth rate, restriction level of resource, symbiotic relationship, partner's behaviour and self behavior. In this paper, adjustments of knowledge transfer input for universities and enterprises to pursue their own maximum interest are analyzed through building dynamic control model. the objective function is calcucated, the equilibrium of cooperative game in knowledge transfer is solved and a simulation analysis in made. In this model, universities and enterprises are the control subjects. They pursue their own maximum interest by adjusting the investment of knowledge transfer. Based on the method of calculating the dynamic control model, the initial value of model parameter is gotten through the empirical research and makes a simulation. Simulation results show that universities and enterprises can adjust the investment according to the knowledge output and knowledge absorption in the system, and then affect the optimal profit ability of industry, universities and research institutes.The increase of the symbiotic effect coefficient and decrease of resource constraints levels is helpful to minimize the Nash equilibrium input and maximize the optimal profit ability. in view of this, In the process of "industry-university-institute" cooperation, universities and enterprises should adjust the investment at any time according to the knowledge output and knowledge absorption in the system to maintain production profitability at a higher level. In addition, in the process of "industry-university-institute" cooperation, universities and enterprises shall establish extensive connection, strengthen mutual exchanges between the two sides, improve the tacit understanding degree and make full use of the symbiotic effect between the two sides.

Key words: knowledge transfer, university-industry cooperation, dynamic control model, cooperative game