In the afternoon, I planned to make some improvement for my work on the Kadis. More datasets should be added into the current framework. The problem in the first place is that the data in the existing database (in fact, excel files) are composed of codes, not corresponding values. That means, some conversion work must be required. When I started to program to do the conversion, I had more questions. 

1. Is the code system in the different dataset the same?

2. Is any rule used to decide these codes?

3. In the integrated dataset, some values in the SITE column don't exist in the code system. Where are they from?

4. In the other dataset, there is no FUI values at all. What to do with such a situation?

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.