(No.3) Information Increase and Electronic Filing
In the former column, it is pointed out that information shifted its media from printed paper to electronic media as mentioned by some intellectuals. According to the estimation of Laurence & Giles (Nature, Vol.400), internet accessible pages played major role in 1990s. their estimation in 1999 of about 800 million pages may grows up to more than 10 billion pages in 2003., if the trend continues. The great volume of information alone does not help us. However combining with emerging technology of information retrieval, we can access freely to this great volume of information.
Why don't we use this benefit at home. I keep fairly large volume of paper like books, magazines, cards and letters. It erodes my housing cost of 1 million yes/ 3.3 square meters. This means I am paying 3000 yen per month without counting interest rate if the house be mortgaged in 25 years. The motivation for electronic filing of personal document is already low:
- ・Low cost hard disk drive,
- ・For easy retrieval, OCR(Optical Character Recognition) is the key
but its cost is going down dramatically as shown in Figure 1.

Figure 1: Price trend of Japanese printed font OCR
The data was drawn from Japanese Industrial Advancement Organizations "Research Report on Office Automation Equipment Standardization Horizontal row numbers indicate the year, and vertical numbers OCR price(10K yen). The arrows in the figure indicate the trend of price change. When software OCR was introduced in 1993, the price went down sharply.
Both OCR and Text Search Engine are available with low cost I started to scan my personal documents at home in August 2001. After 2 yeas the scanned documents summed up as shown in table 1.
| Document type | memory size(GB) | number of titles |
| Technical journals | 13 | 90 |
| Magazines | 13 | 50 |
| Technical papers | 1 | 800 |
| Card & letter | 1.2 | 580 |
| others | 2.1 | - |
| total | 30.3 | ~1600 |
The total number of scanned pages are about 300,000. The approximate thickness is 30 meters. This volume requires at least 3.3 square meters. The cost I paid was 250,000 yen for scanner, 40,000 yen for hard disk drive and 11,000 yen for the software except PC.
Now, I am enjoying frequent use of integrated electronic documents. Table 2 shows the usage statistics of my personal file. As seven years of my cards and letters were scanned, this portion of the database is most frequently used to check addresses, email addresses, and telephone numbers. Newspaper scraps are useful, too. At new year season, I check card file every day.
| Document type | Retrieval frequency |
| Technical journals | 0.2 |
| Magazines | 0.4 |
| Technical papers | 2 |
| Card & letter | 5(exclude card seasons) |
| others | 3 |
| total | 11 |
Here is the unexpected benefit; I do not hesitate to buy an interesting book as before when the book shelves were fully occupied. I am quite satisfied with my investment.
(Ej,2003.09)






