12. A system comprising: a processor; and a memory storing instructions that, when executed by the processor, cause the processor to: perform semantic/syntactic analysis for sentences of a text document to construct semantic-syntactic structures for the sentences; apply production rules to the semantic-syntactic structures to generate a set of logical conclusions about information objects in the text document, wherein the production rules are based on linguistic characteristics of the semantic-syntactic structures, lexical-morphological properties of the semantic-syntactic structures, and ontologies of subject matters for the sentences, wherein the production rules comprise interpretation rules and identification rules, wherein the interpretation rules specify fragments to be found in the semantic-syntactic structures, wherein the interpretation rules specify corresponding logical statements that form the set of logical conclusions in response to finding the fragments in the semantic-syntactic structures, and wherein the identification rules are used to merge ones of the information objects; use the set of logical conclusions about the information objects in the text document to build a Resource Definition Framework (RDF) graph; and store the ontology-based RDF graph in a storage device and provide searching of the stored ontology-based RDF graph as a knowledge base reference.
14. The system of claim 12 , further comprising a database to store the semantic-syntactic structures.