Ontology evolution is a research hotspot in ontology engineering.Nowadays

most of the researches are related with evolution strategies and the technology used in evolution

but there are no clear conclusions for the problem how to scale the ability of ontologies for evolution.This paper solves the problem from a new point of view

that it uses ontology cohesion to determine the degree of ontology evolution.We propose a new Change Transmissibility Model that contains the information of ontology evolution;we define an encoding method called ETMC

which is used to represent the model;we analyze the factors that affect the ontology cohesion and propose an approach to compute the ontology cohesion based Change Transmissibility Mode and ETMC encoding method;we carry out our experiments on two ontologies which describe the same domain knowledge

and the experimental results show that our approach is feasible on the problem of determining the ability of ontology evolution.