Average Co-Inventor Count = 4.84
ph-index = 23
The patent ph-index is calculated by counting the number of publications for which an author has been cited by other authors at least that same number of times.
Company Filing History:
1. Hitachi, Ltd. (31 from 42,535 patents)
2. Hitachi Maxell, Limited (4 from 1,112 patents)
3. Hitachi Computer Engineering Co., Ltd. (2 from 61 patents)
31 patents:
1. 6094647 - Presearch type document search method and apparatus
2. 5832476 - Document searching method using forward and backward citation tables
3. 5757983 - Document retrieval method and system
4. 5748953 - Document search method wherein stored documents and search queries
5. 5745745 - Text search method and apparatus for structured documents
6. 5603003 - High speed file access control method and computer system including a
7. 5548724 - File server system and file access control method of the same
8. 5519857 - Hierarchical presearch type text search method and apparatus and
9. 5497488 - System for parallel string search with a function-directed parallel
10. 5471610 - Method for character string collation with filtering function and
11. 5469354 - Document data processing method and apparatus for document retrieval
12. 5454105 - Document information search method and system
13. 5452451 - System for plural-string search with a parallel collation of a first
14. 5321423 - Document information system and document data transfer and display method
15. 5317606 - Automation system for nuclear power plants