1. Definition of repeated publication: Journals may specify which behaviors are regarded as repeated publication, such as full-text repetition, partial repetition, multilingual publication, etc.

2. Limitation of repetition rate: Journals can stipulate the upper limit of repetition rate, that is, the proportion of papers or similar contents published in other journals or conferences. Periodicals usually require original research, and it is strictly forbidden to publish the full text repeatedly.

3. Citation and recognition: If the research contains previously published achievements or some contents, the journal may require the author to quote and recognize them appropriately to ensure academic integrity.

The Role of Core Journals in Peking University

1. Academic evaluation and recognition: The publication of core journals in Peking University is of great significance to the evaluation and recognition of academic scholars and researchers. These journals enjoy a high reputation and influence in academic circles, and their published research results are often considered to have high academic quality and importance.

2. Dissemination of research results: The core journals of Peking University provide a platform for scholars to widely disseminate research results. By publishing papers in these journals, researchers can promote their research results to researchers in academia and related fields, and promote the exchange and enjoyment of knowledge.

3. Academic exchange and cooperation: The core journals of Peking University also provide a platform for scholars to exchange and cooperate. Scholars can learn the latest academic trends and research directions by reading the research results in these journals, and conduct in-depth academic exchanges and cooperation with other scholars.

4. Influence policy and practice: The research results in the core journals of Peking University often have certain policy influence. Governments, enterprises and other decision-makers can learn from the research results in these journals to provide reference and guidance for policy formulation and practice.