or of other data. These abstracts or data are stored as microimages on a film matrix. The location of each indicated hit is used as the reference point From which to position and project the image of each abstract for visual inspection by the searcher.4.12a One major advantage of microform facsimile torage is the relative ease with which copies of nformation items of interest can be made available o the individual at his desk.4.13 Another advantage beginning to be claimed for certain of the microform nedia is that of erasability and therefore of at least imited potentials for updating, correction, or e-use.4.14 Among the media with this potential capability are some of the photosensitive dyes and hermoplastics.4.15 An important feature of photochromic techniques is the capability provided for on-line inspection and opportunity for limited correction of errors. 4.16 (These and other advanced echniques for high density storage will be discussed n more detail in the third report in this series). Questions of standardization and avoidance of duplication of effort are of concern to designers and users of new or improved microform storage sysems. A significant advance toward systematic efforts in greater cooperation and compatibility was noted in the adoption, first by the U.S. Government,4.17 and second by the United States American Standards Institute, of microfiche standards.4.18

It is to be noted that technological quality control standards are also of importance (e.g., the NBS Microcopy Resolution Test Chart, or line density standards),4.19 that the National Microfilm Associaion continues to be interested in a variety of tandards and standard specifications,4.20 and that two of the three most important objectives of tandardization are already being realized, i.e., 1) recipients of microfiche from the four principal eport-producing agencies are able to interfile nicrofiche, and (2) users are able to use the same quipment for viewing or otherwise processing such nicrofiche." (Schwelling, 1966, p. 36.4.21).

Avoidance of duplication of effort in the preparaion and use of items stored in microform media nvolves current awareness of both existing standrds and of availability of microcopies of various tems in various forms.4.21a The National Register f Microform Masters, issued by the Library of Congress beginning in September 1965, provides a ibliographic record listing titles for which master nicrocopies exist, thus serving to minimize duplicaions of microcopying operations.4.22 National and nternational guides to the availability of microform quipment provide additional sources of informaion.4.23

In terms of the conversion of hard copy to facimile storage media, one particular problem area s that of the range of quality of source items for nput to the microform store.4.24 Another is the question of satisfactory reproduction of multilevel ray scale and of color.4.24a Handling problems are articularly severe in the case of microcopying from ound books.4.25 However, as examples of recent

developments, two models of portable cameras introduced by Data Reproduction Systems in 1965 allow for placement directly over the pages of an opened bound volume,4.26 and competitive capabilities are claimed for a Houston Fearless microfiche camera-processor.4 4.27 Page turners remain a problem. Questions remain as to the relative merits of positive vs. negative images from the point of view of the user.4.28 For archival storage, however, studies at NBS have led to recommendations for storing positive copies together with careful periodic inspections of the filmed records (NBS Tech. Note 261).

4.1.2. Document Store Compacting by Digital Storage Techniques

As opposed to facsimile storage of documentary items and other extensive record collections, document compacting may also be achieved by digitalization of the information contained in the original item or record. The advantages of digital data storage are several fold. First is the advantage of direct accessibility. Accessibility to digitally stored data by an on-line combination of search, retrieval, and display techniques is an important new area of man-machine interaction, as noted in Section 2.2.1 of this report.

Significantly, direct accessibility to digitally stored data can be provided both for machines and for communication links without the need for manual or manual-mechanical handling. This capability leads to a second major advantage: that of manipulatability. Direct machine manipulation of digitally stored data can provide for reformatting of the information stored, for re-orderings of the store itself, for automatic transliterations, and for interconvertibility with respect to multiple modes of input-output and data transmission. Machine analyses of a wide variety of types and automatic report generation techniques are directly available.4.29

A third advantage might be termed "re-computability", which could provide for encoding and decoding of records and messages received (Schatz, 1967, p. 3), stored, retrieved, and re-transmitted. This capability is also available for direct application of error detection and error correction techniques, for machine reconstruction and display of digitized graphic images, and for image enhancement and information enhancement operations such as the cleaning-up of noise in a pattern recognition system. the automatic correlation of synonyms occurring in text, or the resolution of homographic ambiguity by machine examination of contextual clues. (These topics are discussed in other reports in this series).

Automatic machine control of the redundancy of digitally stored information is also in prospect, especially with respect to duplicate checking, validation, and data correlation and consolidation. Such operations may be directed first toward the reduction of duplication as between items stored and with respect to the information contents of various

items. Secondly, such consolidation or correlation may be designed to provide for the validation and verification of information contained in several messages or items. A third purpose of data consolidation is to provide, through aggregation or partial aggregation, protection of the identity of individual reporting units from from unauthorized disclosure. 4.29a

4.1.3. Combined Facsimile-Digital Storage

Since there are both advantages and disadvantages to either facsimile or digital storage, some information processing system design considerations involve various possible combinations of storage media and retrieval techniques. The classic precedent is the Bush Rapid Selector, where the facsimile image on microfilm is directly associated with a digitally recorded selection-criteria encoding and where machine matches of selection-criteria codes in a query with those recorded for stored items automatically trigger the reproduction of the facsimile images of the selected items.4.30

In relatively small-scale and inexpensive systems, a wide variety of digital codes (in edge-notching,4.31 color coding, 4.31a and so forth) are used for "homing" on subsets of items recorded for storage and retrieval in facsimile form or for direct selection of the individual item itself. Similar techniques are employed in some of the more recent large-scale microform retrieval systems, such as Magnavue (to be discussed below).

Then it is to be noted that ". . . the photographic emulsion can also be used to store digital information. If this is done, a reel of film acquires all of the functional virtues of digital tape while avoid ing its information storage limitations. Optical means, such as flying spot scanner techniques, can be used to read the digital information at rates which compare favorably with the electronic reading of digital tape." (Condon, 1963, p. 137). An advanced technique involves laser recording of digitally encoded identification, content-indication, and other selection information on high resolution microforms.4.31b

Another approach to multi-bit storage is that of Lamberts and Higgins of Eastman Kodak who use the recording of diffraction grating patterns on highresolution film involving composites of the grating patterns of seven spatial-frequency components of a character. These investigators point out that this approach is closely similar to that of holography: "In fact, it turns out that a composite grating is essentially a Fraunhofer-type hologram of a series of bright points." (Lamberts and Higgins, 1966, p. 730).4.31c

In general, however, advanced techniques for truly high density storage, promising such possibilities as 13 million bits in a photochromic film memory plane two inches square (Reich and Dorion, 1965), or Honeywell developments indicating potential storage of "two million bits. . . on a surface the size of a dime" (Commun. ACM 11, 66,

Jan. 1968) will be discussed in the next report in this series, concerned with overall information; processing system design requirements.

4.2. Examples of Relatively Direct Access File Storage and Retrieval Systems

The terminology "random access" as applied to mass data and file storage and retrieval techniques is generally misleading. What is usually meant is that the access time to items or records wherever located in the storage medium or device is approxi mately the same for all items and "very much shorter than the initial access time of serial memories". (Licklider, 1965, p. 16). Further, as Poland emphasizes, "only with direct-access, massstorage equipment can randomly related references to data files be made in an economical and expedi tious manner." (Poland, 1965, p. 249).

4.2.1. Retrieval and Reproduction of Microforms

A wide range of equipment is available for the manual, semiautomatic, or automatic (e.g., computer-manipulated 4.32) retrieval, re-enlargement. display, and copy reproduction of conventional microforms such as roll microfilm, microfilm strips and microfilm aperture cards. In addition, systems such as LODESTAR 4.33 and other current developments involve the use of cartridges, cassettes, and magazines to improve access. Relatively recent examples include the VSMF (Visual Search Microfilm Files) System of Information Handling Services. Inc.,4.34 3M's Filmac 400,4.35 and Recordak's Miracode Microstrip Systems.4.36 Other relatively small-scale systems include Remstar 4.37 Randomatic Data System's equipment for keyboarded indexing and retrieval of edge-notched paper, plastic or film cards, the Randtriever System, 4.38 and Mosler Safe Company's

Selectriever. 4.39

the

Examples of commercially available retrieval devices for microfiche in particular include the Houston Fearless Film CARD (Compact Automatic: Retrieval-Display) desktop reader, which provides 4-second (or less) random access to approximately 70,000 pages in any one of a number of interchangeable magazines; 4.40 the Itek 18.24 ReaderPrinter which handles aperture cards, roll film. microfilm jackets, and microfiches up to 5' x 8" with selective masking, variable size print and highcontrast opaque or translucent copies (Systems 6, No. 6,39 (1965).), DuKane's desktop viewer for microfiche in various sizes also up to 5" x 8" at 15 × magnification; Recordak FILMCARD readers; a desktop reader from Data Reproduction Systems; ' the Microcard EL-4 Automatic Enlarger-Printer, and others.

Advanced or large-scale systems are also beginning to come into operation, at least on an experimental basis. Among these are the DARE (Documentation Automated Retrieval Equipment), the Ampex Videofile system, the high-resolution Micro

ue, and SDC's Satire system. Thus, at the U.S. rmy Missile Command, the DARE system utilizes Magnavox Magnavue equipment, under computer ontrol, for a large file of engineering drawings ecorded on film chips.4.41 Also under U.S. Army ponsorship, at Huntsville, developments include ombined usage of Alden/Miracode techniques 4.42 ith the semi-automatic generation of Miracode lm.

The Videofilm techniques involve the storage, etrieval, and reproduction of microforms in the pecial sense of recordings on video tape. The initial ideofile approaches to these techniques at Radio Corporation of America have apparently been at east temporarily abandoned, because of probable igh costs, in favor of RACE, techniques involving he use of relatively large-sized magnetic cards with pertures for optical images.4.43 However, Ampex as embarked on a program of development and marketing of a somewhat more modest Videofile ystem, including remote query capabilities.4.44

The Micro-Vue system developed by the Republic Aviation Division of Fairchild Hiller Corp., involves eduction ratios up to 260:1, so that as many as 0,000 page images can be recorded on a single

x 5′′ microfiche. These "ultrafiches" can be baded into 20-chip holders with random access to ny one of the 200,000 stored images in, at most, O seconds. (Systems 8, No. 1, 6 (Jan. 1967).)1.45 Photochromic materials (as discussed elsewhere n this series of reports) also promise high reducion ratios. For example, developments at NCR nclude the recording of up to 3,000 microimages n a single microform convenient for multiple distriution, i.e., as a microform publication medium.4.45a Other experimental developments in microform torage include work at Aeroflex Laboratories,4.46 and further improvements in both photoplastic ecording and the Photocharge recording process t G.E.4.47 Then there are the successive Walnut, Cypress, and 1350 systems developed by IBM, lthough there is some doubt that any of these will ontinue to be available for graphic storage.4.48 The IBM 1360, a film chip system discontinued after he delivery of two models to the Atomic Energy Commission, was described by Kuehler and Kerby, 966.4.48 However, the high density photographic torage technique has considerable promise for ery large capacity digital data storage, to be considered next.

4.2.2. Digital Data Storage Techniques The media and methods available for digital data torage include high-resolution photographic naterials, magnetic media, advanced developments sing laser recording techniques, and other special

materials and techniques. For high density digital data storage, magnetic technique developments include larger and higher-speed bulk core storage, especially with new types of tiny cores;4.49 discs and disc pack units with capacities ranging to billions of bits of data and access times of 100 or less milliseconds;4.50 drums,4.51 and magnetic cards and data cells.4.52

Pyke summarizes the current situation with respect to magnetic media as follows: "A large effort is now being expended on the development of mass storage devices. Larger and faster bulk cores are being designed. Drums operating with parallel transfer and with logic for queuing access requests, thus optimizing drum operation, are forthcoming. Disk units with an individual head per track are becoming available and devices such as data cells. promise many billions of bits of storage at a reasonable cost." (Pyke, 1967, p. 162).

From an applications standpoint, Bonn emphasizes that "the currently used devices are drums, disk files, magnetic card devices, and tape loop units. These machines all store large amounts of data, from 6.5 million to 4.8 billion bits, on-line in one device at any one time. Any of the stored information can be retrieved without reading the intervening data between two desired records. Any record can be written or modified without operation on any other record. Records in mass storage devices can be updated in place." (Bonn, 1966, p. 1861).

In the area of advanced developments for digital data storage involving electron or laser beam recording onto photographic media, semiconductor films, or thin metallic foils, examples include the Dove Data Storage and Retrieval System,4.53 IBM's "trillion-bit" memory recently delivered to the Atomic Energy Commission,4.54 and the UNICON technique developed by the Precision Instrument Company.4.55 In addition, Kump and Chang (1966) provide a discussion of a thermostrictive recording technique for Permalloy films, achieved by the application of local stresses induced by laser or electron beam, which is claimed to promise future mass memories with storage efficiencies of a million bits per square inch.

Then we note, on the one hand, that portable digital data storage modules are under development that will enable interchangability on standard input/ output equipment, much as magnetic tapes reels are now handled,4.56 and that, on the other hand, "breakthroughs we seek in mass memory may come from the molecular engineers, who can develop improved materials with which we can fully exploit the inertialess properties of light and electron beams to write and read data bits closely approaching molecular size." (Hoagland, 1965, p. 57).

In Figure 5, we show some of the areas of continuing R & D concern with respect to the output and postprocessing functions. It has been claimed that, in general, too little attention has been given to

output requirements in information processing system design.5.1a Further, it is noted that "the completeness, accuracy, and accessibility of system outputs are each individually dependent upon system design and can be improved through improvement in system design." (Davis, 1967, p. 8). First, advanced developments of direct output modes with interactive man-machine response may be considered, especially with respect to graphic displays, to applications such as computer-assisted instruction and machine-aided design, and to prospects of color, three-dimensional and motion. picture outputs.

5.1. Direct Output and Display Applications

Direct output and display requirements for the foreseeable future encompass a wide variety of user-oriented capabilities, some of which are commercially available on at least a limited basis today and some of which will require further research, development, and production engineering. Application areas of current R & D concern include those of computer-aided instruction, machine-aided design, and machine-aided problem-solving systems.