No matching global declaration available for the validation root

You need to change your XML instance. Your current one says that there is a type called description in the namespace http://www.namespace.org/recipe. However, in your XSD definition, the only types exposed in that namespace are called recipe and descriptionType.

So either define a type called description in the XSD schema, or change your instance so you are referencing the recipe type correctly:

File ns-changed.xml:

<?xml version="1.0"?>
<r:recipe xmlns:r="http://www.namespace.org/recipe">
  <description>
    <title>sugar cookies</title>
  </description>
</r:recipe>

UPDATE This is only half the solution – the other half is in @Aravind’s answer here: https://stackoverflow.com/a/8426185/569662