SCI is an international retrieval publication, including natural science, biology, medicine, agriculture, technology and behavioral science. , mainly based on basic science. The selected publications come from 94 categories, more than 40 countries and more than 50 languages. These countries mainly include the United States, Britain, the Netherlands, Germany, Russia, France, Japan, Canada and so on. , including a certain number of China publications.
EI: Engineering Index (EI for short) was founded in 1884, which is a well-known comprehensive retrieval tool for engineering technology published by engineering information companies. EI is published every month in 1 issue, with an abstract of 1.3 million to 1.4 million; Each issue is accompanied by a subject index and an author index; There is also an annual volume and an annual index every year, and the annual index also increases the author unit index. The collected literature covers almost all fields of engineering technology. For example: electric power, electrician, electronics, automatic control, mining and metallurgy, metal technology, machinery manufacturing, civil engineering, water conservancy and so on. It has the characteristics of strong comprehensiveness, wide data sources, wide geographical coverage, large amount of reports, high quality of reports and strong authority.