Genetic algorithm implementation for effective document subject search

The quality of documentary subject search or search for documents containing specifically coordinated information on a target subject is not always satisfactory. Despite the availability of powerful search engines for information resources on the Internet or special databases, the process remains time-consuming and poorly supported by software and methodologically. This paper describes the software implementation of genetic algorithm for identifying and selecting most relevant results received during sequentially executed subject search operations. Simulated evolutionary process generates sustainable and effective population of search queries, forms search pattern of documents or semantic core, creates relevant sets of required documents, allows automatic classification of search results. The paper discusses the features of subject search, justifies the use of a genetic algorithm, describes arguments of the fitness function and describes basic steps and parameters of the algorithm. It is noted that the fitness function or quality criteria determined by the position of the document in search results built by the search engine for maximum number of different queries and semantic similarity of search pattern of documents on a given subject. Software implementation is described in detail: the general object model, user interface, the main library of the algorithm, morphological analysis module, texts similarity analysis module, search module, database management module, metadata management module. The information on module classes composition and components is provided. The paper describes genetic algorithm software implementation that is one of the elements of project Intelligent Distributed Information Management System for Innovations in Science and Education powered by the Russian Foundation of Basic Research. The algorithm plays an important role in functioning of the adaptive search engines. It is noted that developed algorithm software creates a sufficiently broad basis for further research and development.