SAP Analytics Cloud New Model Update Existing Dimensions with new Fields

Hello,

I have noticed that i am unable to add new Fields to existing dimensions neither their hierarchy or description, for example:

Account Dimension

ID -----------------------Description-------------Hierarchy

1. Asset 1 ------------Car---------------------Assets
2. Asset 2 ------------Plane------------------Assets
3. Asset 3 ------------ Building -------------Assets

and would like to add the following fields through datasource/excel

ID------------------------ Description------------Hierarchy

1. Asset 4-----------Land ---------------------Assets
2. Asset 5 -----------Factory -------------------Assets
3. Asset 6 ----------Machine------------------ Assets

is that possible with the new model and if so how?