Many other researchers , , , , , ,  used ontologies, inverted list (different tech.
The system builds inverted list based on the biological terms only that exist in the corpus's documents.
The system uses the inverted list to get the list of the documents that satisfy the query Q.
By clustering d-gaps of an inverted list based on a threshold, and then encoding clustered and non-clustered d-gaps using different methods, we can tailor to the specific properties of different d-gaps and achieve better compression ratio.
Keywords: Inverted file, d-gap, Index compression, inverted list
Assuming a text collection composed of a large set of documents, an inverted list is basically composed of a table (the vocabulary) that maintains all the relevant words found in the text, and an associated list for every such word that registers all occurrences of the word in the text (document-id and another information used to rank out responses to users queries) .
In previous works, parallel algorithms for the local inverted list and global inverted list strategies have been developed, using an analysis and well structured design methodology, through the BSP computing model [7, 9].
For instance, one inverted list
index generated from a customer table might include all the states (AK, AL, AR, etc.
We assume that the index is implemented using an inverted list which, as described in the next section, is composed of a vocabulary (set of terms) and a set of identifiers representing all the documents that contain at least one of the words that are members of the vocabulary.
However, when the differences between inverted list sizes is small, the efficiencies of the global approach are competitive.
Some specific topics covered are disparity mapping for navigation of an autonomous guided vehicle, automatic refinement of platform independent models, character-based indexing using inverted lists
, and web service QoS prediction based on multi agents.
They show that an intelligent scheme for packing inverted lists
in the storage structures of the database can provide performance and storage efficiency comparable to tailored inverted file implementations.