Which tools can be used to search patent?
A: Espacenet patent search
B: WIPO Patentscope
C: CNIPA patent search and analysis
D: USPTO patent search
A: Espacenet patent search
B: WIPO Patentscope
C: CNIPA patent search and analysis
D: USPTO patent search
举一反三
- There three types of patent in China, Patent for Invention, Patent for Utility Models and Patent for .
- OVID-medline数据库有哪些检索方式( )。 A: Basic Search B: Search Tools C: Advanced Search D: Search Fields
- Once a patent expires， an invention becomes common property and can then be freely used by anyone。（ ）
- Which research method can be used to collect primary data? A: Statistical analysis B: Observations C: Online search D: All of the three.
- Which type of search engine presents a list of topics or categories from which you select subtopics until your search is narrowed to a list of Web sites? A: Directory search B: Keyword search C: Metasearch D: Reference search