The classes are not defined as visible. Read carefully the Extending the KIM ontology and knowledge base section in the Developer's guide.
You should also re-deploy the KIM web application container. For example, if you are using Tomcat, you do it by removing the unpacked files from tomcat-home/webapps and clearing the tomcat cache in tomcat-home/work.
If you are using the KIM-integrated Jetty web server, you don't need to do anything, just restart the KIM application.