Systematizing the array of dissertations in individual discipline based on chronologizing of Ph.D. defenses and title content-analysis. (Part 1)

The author explores the array of doctoral dissertations in the area of forest engineering, forestry technologies and machines, submitted in the period of 1955–2022 (190 dissertations). The bibliometrical analysis enabled to specify 5 time periods differing in their dynamics (1955–1962; 1963–1970; 1971–1989; 1990–1999; 2000–2022). Before 1993, there were two defense hubs, namely Moscow and Leningrad (now St. Petersburg); after 1993, regional hubs emerged. In 1993–2022, 68% dissertations were defended in the regions outside Moscow and St. Petersburg; 14% dissertations were defended in two disciplines. On average, 16 years were passing between scientist’s candidate and doctoral dissertations, however, since 1994, this difference may make less than 10 years – 24% papers in 2009–2022. In 1955–1982, the keywords “study”, “problems”, “basics” dominated in the titles, and since 1986 – “feasibility”, “increase”, and “improvement”. After 2006–2008, the number of titles including “feasibility” decreased, and the word combination “refining the theory (method)” became popular. Since 1986, the vector of studies changed from process and system studies toward their modernization and enhancement. Through classification by the research subject, 42 topical areas were specified, and then divided into two groups. Within the group one, the papers can be bundled (over 3 dissertations) and make subject fields where their own systematization is possible. In the group two, the dissertations make the individual studies (103 papers) that can hardly be consolidated into the array. Within several topical field, the cyclicism is observed – the dissertations are defended regularly. The content analysis of dissertation titles coupled with bibliometrical methods, reveals the more regular pattern within the individual specialty. The obtained findings will be demanded by researchers and professionals engaged in scientometrical and bibliometrical research.