centralization vs concatenation

centralization

noun
  • The act or process of centralizing, or the state of being centralized; the act or process of combining or reducing several parts into a whole 

concatenation

noun
  • A series of links united; a series or order of things depending on each other, as if linked together; a chain, a succession. 

  • The application of these series of links. 

  • The operation of joining multiple character strings. 

  • A character string formed by joining multiple character strings. 

How often have the words centralization and concatenation occurred in a corpus of books? (source: Google Ngram Viewer )