I start to working on solutions to the conflicts when merging different ontology files. Before he left, my advisor suggested me reading some materials of Null Value processing in the database. I read the first sections of the paper wrote by him some years ago. I have to stop and make a though that what the point of this paper is. Is it useful when is applied to the resolution of conflicts? I am doubting. 

In his paper, the method presented deals with the null values of different semantic meanings in the relational database in A general way. At this time, I suddenly found that I didn't understand the very method completely, so that I'd better read the whole paper first. 

The first step is to get some basic background knowledge of this topic. In the afternoon, I found some papers, which are mainly related to XML. I believe that our work will lie on the process of XML document. The subject is focused on the formalized representation, logical structure, and inconsistency process etc. Until now, I can not make sure anything I do is useful, but it's necessary. 

On the other hand, I have some other tasks. What I can figure out just now are as the following: 

1. Kadis: ontology document and database for two dataset;
2. Join component: going over the old work and adding new functions.