DOI stands for Digital Object Identifier （ D igital O bject I dentifier ） ,
and is the unique identifier for objects on the internet. It can be used to create persistent link and to cite articles.

Using DOI as a persistent link

To create a persistent link 「 https://doi.org/ 」 before a DOI.
For instance, if the DOI of an article is 10.5297/ser.1201.002 , you can link persistently to the article by entering the following link in your browser: https://doi.org/ 10.5297/ser.1201.002 。
The DOI link will always direct you to the most updated article page no matter how the publisher changes the document's position, avoiding errors when engaging in important research.

Cite a document with DOI

When citing a document with a DOI, the DOI permanent URL should always be presented (if using APA or Chicago format, present https://doi.org/DOI number). If using a citation format that does not specify DOI, the DOI permanent URL should still be presented as a priority.

DOIs allow accurate citations, improve academic contents connections, and allow users to gain better experience across different platforms. Currently, there are more than 70 million DOIs registered for academic contents. If you want to understand more about DOI, please visit airiti DOI Registration （ doi.airiti.com ） 。

ACI:

Data Source: Academic Citation Index (ACI)
As Taiwan's largest Citation Index, we currently have on record all Humanities, and Sociology journals that were published in Taiwan. The number of periodicals that are published on a regular basis total around 400 different types. If periodicals that were added to the collection but then halted are counted as well, the number of periodicals total over 500 types. Every year we announce the recorded periodicals' impact factor, etc. to the public, and allow scholars utilize our materials to carry out academic research for free.

Impact Factor: The statistic indicating the average number of times a journal's articles published in the past two years have been cited in the counting year.
Formula: (Number of cites in counting year to articles published in the span of two years ) ÷ (Number of articles published in the span of two years)
Example: The impact factor in 2010 (determined in 2011)
In 2009, Journal A published 15 articles, and these 15 articles were cited 20 times in 2010.
In 2008, Journal A published 16 articles, and these 16 articles were cited 30 times in 2010.
→ →2010's Impact Factor = (20+30) ÷ (15+16) = 1.61 =（20+30）÷（15+16）≒1.61

What is "Preprint"?

To provide readers with the forefront academic information, articles that have been accepted for publication in journals and published online before the printed version are known as "preprint articles", which increase the article's exposure. Preprint articles do not have volume, page numbers, or publication dates yet, but can be identified by their DOI number. The DOI number is a digital identification number for literature. Both preprint and officially published articles will be assigned a DOI number. Through database integration, readers can easily follow the complete publication process of the article by clicking on the DOI link 「 https://doi.org/DOI Number 」

How to cite Preprint Articles?

You can use the year it was published onlineand DOI link of the preprint article to cite the literature.

Here is an example of a citation (based on APA 7th edition, which may vary depending on different citation format standards):

Author name (year of online preprint article). Article title. Journal name. https://doi.org/DOI Number