What type of database is pqdd?
PQDD (ProQuest Digital Dissertations) is a digital doctoral and master's thesis abstract database. It was developed by ProQuest Company of the United States. It has included more than 1.6 million records, covering all the world's papers approved in 1861. The first doctoral thesis (U.S.A.), information on doctoral and master's thesis that have been approved by this semester of this year.
In addition to the citations related to each paper, the database also includes a 350-word abstract written by the author himself in the doctoral theses published after 1980. Information on master's theses published after 1988 includes a 150-word abstract. More than 55,000 new paper entries are added every year.
For electronic copies of papers published after 1997, users can browse the first 24 pages of these papers for free. The database has a complete version and two volume versions, namely Series A and Series B. Series A is mainly the humanities and social sciences edition, and Series B is mainly the science and engineering edition.
PQDD provides a total of 14 fields for retrieval. Commonly used fields include: title, abstract, author, advisor, school, subject, and year. (year), language (language), etc.
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