US3964029A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Information retrieval systems
Assignee: Fujitsu Services Ltd
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Filing: 1975-04-14
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Granted: 1976-06-15
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Expires: 1995-04-14
Abstract
Abstract An information retrieval system in which each record in a file is scanned and a hit signal is produced if it matches a search criterion. The hits are stored in a plurality of bit maps. Each record has an identifying index, which is transformed in a number of different ways to produce addresses for the bit maps. The outputs of the bit maps are combined to produce a stored hit signal. The number of hits is compared with the number of stored hits to determine whether any spurious stored hits have been recorded and, if so, the transformations are modified.
Inventors
- 👤 Edward Babb
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 17:14
CPC Classifications
G; G06; G06F; G06F16/00; G06F16/90; G06F16/903; G06F16/90335; G06F16/90344; Y; Y10; Y10S; Y10S707/00; Y10S707/99931; Y10S707/99933; Y10S707/99936
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
158 words
An information retrieval system comprising: a file store holding a plurality of records each having an index which identifies that record, a plurality of storage areas each having a plurality of individually addressable bit locations, the total number of such locations being smaller than the number of records in the file; means for operating on an index in a plurality of different ways to produce a plurality of addresses, one for each storage area; means for searching the file to compare each record with a search criterion and to produce a hit indication whenever a record is found which satisfies the search criterion; means responsive to a hit indication to write a predetermined pattern of bits into the addressed locations of the storage areas; and means for reading out the contents of the addressed bit locations of the storage areas to produce a stored hit indication in the event that those locations contain the predetermined pattern of bits.
Claim 2
Dependent Claim
158 words
An information retrieval system comprising: a file store holding a plurality of records each having an index which identifies that record, a plurality of storage areas each having a plurality of individually addressable bit locations, the total number of such locations being smaller than the number of records in the file; means for operating on an index in a plurality of different ways to produce a plurality of addresses, one for each storage area; means for searching the file to compare each record with a search criterion and to produce a hit indication whenever a record is found which satisfies the search criterion; means responsive to a hit indication to write a predetermined pattern of bits into the addressed locations of the storage areas; and means for reading out the contents of the addressed bit locations of the storage areas to produce a stored hit indication in the event that those locations contain the predetermined pattern of bits.
Claim 3
Dependent Claim
79 words
A system according to claim 1, further including means for counting the number of hit indications produced during a scan through the file, means for counting the number of stored hit indications produced during a subsequent scan through the file, and means for comparing these two numbers and, if the latter number is larger than the former, modifying the operations performed on the index, the scanning and modifying being repeated until the two numbers are found to be equal.
Claim 4
Dependent Claim
21 words
A system according to claim 1, wherein the storage areas are provided by respective separate memory devices, and are addressed simultaneously.
Claim 5
Dependent Claim
29 words
A system according to claim 1, wherein the means for operating on the index comprises means for selecting a plurality of different combinations of the bits of the index.
Claim 6
Dependent Claim
28 words
A system according to claim 1, further including means responsive to stored hit indications for retrieving a specified item of data from those records which produce such indications.
Claim 7
Dependent Claim
32 words
A system according to claim 1, further including means responsive to stored hit indications and to hit indications, for retrieving a specified item of data from records which produce both such indications.
Claim 8
Dependent Claim
30 words
A system according to claim 1, wherein the number of storage areas is substantially equal to n.sub.opt = log.sub.e A where A = r ÷ H (R 1 - 1)
Claim 9
Dependent Claim
45 words
r = the number of records in the file H = the average number of hit indications produced during a scan through the file R 1 = r/h and R = the average number of stored hit indications produced during a scan through the file.
Claim 10
Dependent Claim
45 words
r = the number of records in the file H = the average number of hit indications produced during a scan through the file R 1 = r/h and R = the average number of stored hit indications produced during a scan through the file.
Claim 11
Dependent Claim
25 words
A system according to claim 7, wherein the total number of bit locations in the storage areas is substantially equal to b.sub.opt = H.e.log.sub.e A
References Cited (Backward Citations)
US3358270A
Cited
US3484751A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-06-15 | 1979-12-15 | 1980-06-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-06-15 | 1983-12-15 | 1984-06-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-06-15 | 1987-12-15 | 1988-06-15 | $7700.00 | Window Closed / Lapsed |