4.42 "DOCUS, developed by Informatics for the multicomputer complex at Rome Air Development Center, provides a display-oriented manmachine system with some built-in data management functions and a capability to assign functions to control keys at the display and define an execute compound functions based on earlier defined tasks." (Minker and Sable, 1967, p. 137). Other examples viewed generally with favor in the literature include the following:

(1) "Placing control functions on the scope face has two advantages. First, only those controls which should be present at a particular stage of a problem are displayed. If a light button labeled 'MOVE' is one of those present, a user knows that he can move picture parts around. Similarly, if only light buttons in the form of PNP and NPN transistor symbols are displayed, a user knows he must select a particular type of transistor at that time. Thus, in effect, a user is steered through a problem. Second, during most operations there is only one center of attention, the scope face, on which a user need concentrate. This allows faster and smoother work on a problem." (Ninke, 1965, p. 845).

(2) "STATPAC, a program for scientific data analysis, allows an experimenter to apply various statistical operations and mathematical transformations to data simply by light-penning a desired operation chosen from a list of operations displayed on the scope." (Baker, 1965, p. 431).

(3) "This [SDC Variable Display] program is intended to assist in the design of tabular displays. It permits a user to sort, delete, insert and exchange rows and columns of information presented in matrix form on a display console. Actions can be taken by both light-pen and teletype input." (Schwartz et al., 1965, p. 30).

.

(4) "These programs . . [may lead the operator] by providing information on the next step, by informing him which next console steps are permissible, or by signaling him when a console step has been initiated which is not permissible." (Bauer, 1965, p. 22).

4.43 "The major limiting factor in further improvement in light-pen speed is in the phosphor screen itself, which must be of a persistent type in order to reduce display flicker. . .

"We have developed a system to detect the electron beam causing the screen light rather than the light itself [as a new approach to in

creasing the speed of the CRT display system for man-machine communication..

"From experimental evidence we conclude that it is possible to make a system to detect when and where the electron beam of a CRT strikes the screen, thus essentially eliminating the bandwidthlimiting effects of the CRT phosphor and making a high-speed man-machine communications system possible." (Haring, 1965, pp. 848, 854).

"Current development work on CRT's is concentrated heavily in the search for new phosphors to provide increased brightness and longer life." (Mahan, 1968, p. 19).

"Both electroflors [liquid phase materials that fluoresce or change color when small electric currents are passed] and piezoelectric displays show promise, but are hardly beyond the feasibility state of development. Current research spending is not very heavy for these displays so few results are expected in the near future." (Mahan, 1968, p. 28).

4.44 "The use of analog predictive circuitry should be explored as a possible means of improving tracking performance. The simple noise filter in the present experimental circuit serves to provide velocity prediction in the sense that the voltage on the filter capacitor is the average of past error voltages. If an error signal should fail to be developed over several cycles, the voltage on this capacitor would provide tracking continuity." (Stratton, 1966, p. 61).

"The merit of the analog technique lies in the small processing time required to determine the position of the moving pen. Decreasing the tracking interval allows more time to be utilized for display - a particularly important consideration when many consoles share the same display channel." (Stratton, 1966, p. 58).

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4.45 . . . The computer may be operated in a multisequenced fashion... One sequence may be used to calculate a file of point coordinates for display and a higher priority sequence may be used to display these points. In this manner, the high priority display sequence insures that points are displayed as often as possible so that the picture does not flicker objectionably as a result of the computation of new points usurping display time." (Loomis, 1960, p. 2).

4.46 "Research and development work on several display technologies offer promise for improved real-time large screen displays by the early 1970's. These include.

Photochromic displays with cathode-ray-tube or laser image generation

Thermoplastic and photoplastic light valves with cathode-ray-tube or laser-image generation Crossed-grid electroluminescent displays with integrated storage

Laser inscribing systems
Solid-state light valves
Opto-magnetic displays

Electro-chemical displays

Injection electroluminescence matrix displays." (Hobbs, 1966, p. 42).

4.47 "Large-screen displays are used where it is necessary for a group of people to view the same information simultaneously. Because of the cost involved in implementing large-screen displays, their use has been confined largely to military systems. The high cost plus the lack of really adequate technologies for presenting dynamic information on a large screen have seriously restricted the use of group displays. Significant technological improvements are necessary to permit satisfactory group displays at a reasonable price before their utilization will become widespread in the commercial world. Most group displays that have been installed to date involved projection systems of one type or another with the display generated in one device and then projected onto a screen. However, work is underway on several technologies that will permit the generation of the visual image in the screen itself. Some of these are considered later in the discussion of display technologies. Most of the research and development on the visual transducer portion of display systems is devoted to techniques applicable to large-screen displays because of the lack of suitable means for implementing displays of this type at present. The CRT enjoys a dominant position in console displays, but there is no equivalent dominant technology for large-screen displays." (Hobbs, 1966, pp. 1871– 1872).

"While large scale display techniques have advanced considerably in the past few years, there is still much room for improvement. Their capability to handle dynamic data needs considerable expansion. Cost which is now high must be lowered and reliability needs improvements. . . .

"Toward this end, considerable research is now underway to improve existing techniques. New films which do not need wet chemicals are being explored along with novel methods of processing conventional films. Considerable effort is under way to improve the performance of the light valve technology. Also, new and better techniques are being developed to convert digital data to the analog form necessary for the exploitation of TV type devices." (Kesselman, 1967, p. 167).

4.48 "When data phones are used in the communication link, experience with existing display systems indicates that several data phones are required to handle many user consoles from a single buffer/controller. Data phones now available for switched telephone networks provide approximately 2000 bits per second of data, but within the near future this rate may be approximately doubled, according to information received from the telephone company. Since one CRT frame contains approximately 20,000 bits, at least ten seconds is required to transmit a complete single frame. Fortunately, the majority of the messages between

the user and the time-shared computer will be on the order of one line of text requiring only one-third of a second. However, since a single user might wish to request up to five frames at a time, a maximum of 50 seconds might be required to serve a single user. In order to avoid prolonged delays in service to other users who may be awaiting service at that instant, one 2000-bps data phone must be dedicated to a small number of consoles, or the servicing of the consoles must be interlaced, or combinations of these two must be employed. At the present time, our thinking runs toward use of one data phone for every three consoles, and interlacing the service to provide response time of less than 30 seconds under worst-case conditions. Since, in actual practice, users most frequently will be sending and receiving much less than a complete frame and furthermore, since the probability that several users will be communicating data simultaneously is very small, as regards the communications delays, the service would typically be less than a second." (Haring, 1968, pp. 38-39).

"The video buffer contains the necessary electronics for head selection, writing, and sync mixing. Each head is in a read (or display) mode except when writing, and a single write driver serves all the heads." (Terlet, 1967, p. 172).

Roberts suggests that "it is possible. . . to time-share one vector-curve generator for several display units if the generator is fast enough to eliminate excessive flicker. Each display then receives the common deflection signals, but is only intensified when the segments being drawn are intended for that unit. This technique allows the generator cost to be shared by up to four displays at present speeds." (1965, p. 217).

"In order to reduce the cost of individual consoles, it is advantageous to cluster consoles around a local station which includes data storage and processing that is common to all clustered consoles. Initial investigations indicate that it should be possible to design economical console systems which cluster about ten consoles at distances of a thousand feet from a local station. Thus, the consoles could be placed in several different rooms of a single building. Interconnections between the consoles and the station are made with coaxial cables, while the connection between the station and the time-shared computer utility are made by common carrier. In the future, a high-speed photographic printer will be located in the vicinity of the console to produce hard copy on command from any of the consoles." (Haring, 1968, p. 258).

4.49 "Human factors, habit patterns, etc., have to be considered with respect to both operation of the terminal and designing new procedures." (Duffy and Timberlake, 1966, p. 273).

"We have planned a survey of man-machine relationships, both at present and with contemplated systems, from two points of view: (1) man-machine relationships from the standpoint of human engineering principles, and (2) the relationships from

the standpoint of the attitudes of the people who will be operating the system." (Sharp and McNulty, 1964, p. 2).

"Heretofore not much has been said about the mechanical design features of the consoles. A great deal of design effort is being applied to the human engineering aspects of the consoles since it is imperative that the user's initial contact with the consoles, the only part of the Intrex experimental library which the average user sees, be a pleasant one. The objectives here are to retain sufficient flexibility in the initial consoles to permit effective user evaluation of various features and options while at the same time to maintain a finished look to the consoles.” (Haring, 1968, pp. 263–264).

"Human errors and the education of human beings are, therefore, two systems design factors which must receive significant attention. The systems designer must understand the chief motivations of the terminal operators. Wherever possible, he must design into the system factors which will lead to operator satisfaction as a result of successful operation of a terminal. Operator education, both at the start and on a continuing basis, must also be carefully planned. This is particularly true for systems which may expect a significant turn-over in terminal operators within a relatively short period (e.g., 6 months to a year) after the initial implementation of the system. Operator education must be recognized as a continuing system function. Wherever possible, means for providing education or guidance for operators should be designed into the terminal device or the system as a whole.

"The efficiency of the terminals and the system, and the degree of intrusion introduced by the system into the regular jobs or occupations of the terminal operators, also must be considered. Many people in the organization will assume a second role as a result of the information system. In addition to their regular job, they will now also be expected to act as a recorder of data. As a result, human factors will be extremely important in the design of terminal devices. This will insure that the data recording operation is as simple and straightforward as possible, and requires a minimum effort from the terminal operator." (Pedler, 1969, p. 30).

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4.50 Interface', with its connotation of a mere surface, a plane of separation between the man and the machine, focuses attention on the caps of the typewriter keys, the screen of the cathode-ray tube, and the console light that wink and flicker, but not on the human operator's repertory of skilled reactions and not on the input-output programs of the computer. The crucial regions for research and development seem to lie on both sides of the literal interface." (Licklider, 1965, p. 92).

4.51 "The 'process' keys would be used to institute queries to specific portions of the automated catalog and to respond to the next steps suggested by the automated system. At least a 120-character or symbol set would be desirable, in contrast with the 64 characters typically available

now. This means that effort will have to be placed on new or improved and certainly more economical means of character generation.” (King, 1963, p. 19).

"Several basic hypotheses resulted from the study program and have been used in the formulation of the initial design concepts. First, it is advantageous to handle many routine operations at the console in order to minimize communication between the console and the time-shared computer. This approach reduces the demands on the central computer and should result in more rapid access to the central machine when required. It further reduces the cost of transmitting information from the time-shared computer to the console, an important consideration in any large operational system. Second, careful attention should be given to the size and content of the console alphabet, the ability to produce superscripts and subscripts, and to the human engineering aspects of the console in order to ensure favorable user reaction to the console and to the overall system. Third, it must be possible for the uninitated user to become familiar with the operation of the console and the catalog system rapidly and easily. Finally, the design of the console should be such that it can be economically reproduced. This feature is a necessary prerequisite to the wide-scale user of computer-based library systems." (Haring, 1968, pp. 257-258).

4.52 "Careful planning of systems outputs may permit the complete specification of all files to be maintained and the input entering such files. Let us examine input first. The systems designer must be concerned with content. All needed data to be printed in reports must first be entered into the computer. In addition to this substantive data, the designer must also consider any necessary control data which must be part of the input to the computer. For example, if the system is to use sophisticated photocomposition equipment with an expanded character set, then typographic symbols must be included in the computer input. For example, upper and lower case indicators must be entered, variations in sizes of type to be used on the composer, indications of which characters are to be printed in bold face, which are to be printed in italics, etc. . .

"The character set to be employed in a system is an obvious important factor in systems design. The designer must consider how sophisticated a character set is required. He must decide whether on the basis of the user's requirements upper and lower case characters are needed, whether different sizes of type would be useful in preparing publications, whether the Latin alphabet is adequate or whether Cyrillic characters must be provided. He must also determine the requirements for special characters such as diacritical marks required for certain foreign languages or subscripts and superscripts needed for chemical notations." (Austin, 1966, pp. 243–244, 245).

4.53 "In a comprehensive chemical data. processing system there is a real need to input

and output conventional molecular or empirical formulae, various nomenclatures, structure formula diagrams, and considerable generic information and data. To accomplish the output function, the system analyst was, until recently, limited in his choice of output hardware. This restraint led to the use of numerous and often cumbersome coding techniques and printing conventions which must very often be learned by the chemists themselves." (Burger, 1964, p. 1).

"Examples of elaborate code conventions adopted for keypunching of text include reports by Nugent (1959) and by Ray (1962), both of which point out some of the requirements and some of the difficulties encountered with respect to providing a manual for the keypunching of natural language texts. An even more sophisticated encoding-transliteration scheme is detailed by Newman, Knowlton and Swanson (1960) as necessary for the keypuching of patent disclosures in which a very wide variety of boldface, normal, italic faces and of special symbol insertions must be provided for. . .

"Flexible selection from amongst a large variety of available characters and symbols may thus be provided for, but at the high expense of multiple initial keystroking, multiple code-sequence processing and redundant storage requirements for each 'actual' character eventually to be reproduced. For example, with respect to the early Barnett experiments using Photon, it is claimed that the proportion of control and precedence coding to actual character-selection identifications could run as high as 75 percent of the total input. While possibilities for re-design of keyboards and for multiple-output from a single key depression may alleviate this problem somewhat, the difficulties of precedence coding to achieve larger and more versatile character sets remain a major problem area." (Stevens and Little, 1967, p. 75).

"As an output device. . . the painfully slow printing rate [of the teletypewriter] impedes all but the dullest of men. Its limited symbol set, and its rigid format for placing characters on a page, makes its display of information very minimal. Graphs come out as x's on a page, giving only the coarsest possible feel for the information. Mathematical expressions must be coded in such a complicated shorthand that only the program's author can interpret it without a guidebook." (Stotz, 1968, p. 13).

see the use of parallel-key devices, based on the stenotype principle . . ." (Ohlman, 1963, p. 194).

"If a data file is extremely redundant (such as a natural-language text) then the stenotyping technique cuts the number of keystrokes required by as much as two-thirds." (Partick and Black, 1964,

p. 43).

"The automatic conversion of stenotyping is being actively pursued with the aim of reducing the cost of file conversion." (King, 1963, p. 9).

"... The central problem of keyboard design is to get a large selection of codes from a limited, properly spaced, simple-to-operate arrangement of keys.” (“The (R)evolution in Book Composition . . . IV," 1964, p. 68).

"It may be that we shall have to wait for more fundamental research to clear the way for a chord typewriter, played more like a piano." (Duncan, 1966, p. 264).

"If it turns out, as seems likely, that very large ensembles of characters are desirable in mancomputer interaction with the body of knowledge, then it will become much more important that it is now to be able to specify the desired character by pressing a pattern of keys on a small keyboard. That is a much better solution than pressing a single key on a keyboard with several thousand keys." (Licklider, 1965, p. 100).

4.56 The case of chemical information is even more demanding: "It is difficult to devise an algorithm that allows the sorting process to ignore characters that should be ignored in traditional alphabetization of chemicals. For instance, 1,3dimethyl is alphabetized under M, dimethylaminopropyl under D, and 1,3-bis(dimethylaminopropyl) under B. Using a flexible listing order that can be specified for the index solves the ordering problem in this system; editorial work is, of course, a consequence. The advantage of flexibility in the face of a difficult problem was considered sufficient justification for this effort." (Tinker, 1968, p. 324).

4.57 Problems of character-set repertoire are particularly acute in the areas of primary publication of scientific and technical texts, bibliographies (e.g., in the Besterman World Bibliography of Bibliographies, 1950 different pieces of Monotype characters were used) (Shaw, 1962, p. 268) and in library card catalogs.

Ohringer comments: "There will be many formulas and special mathematical symbols interspersed with the text. The type fonts used tend to vary greatly, including many Greek letters in addition to many styles and sizes of Roman alphabet. The page arrangement also contains too much variation for present-day optical character readers." (1964, p. 311).

4.58 "A character set for instruction must often include a far larger number of characters and symbols than is needed for other applications. For example, teaching a foreign language may require that two different alphabets be displayed at once. In mathematics, a display must often include ex

ponents, subscripts, and fraction lines, as well as alphanumeric characters and mathematical symbols." (Terlet, 1967, pp. 169–170).

"Primarily because of the complex chemical names, chemical information publishing demands the use of the Roman and Greek alphabets, upper and lower case letters, several type fonts (italics, boldface, small capital letters), and superior and inferior positions. In all, nearly 1500 symbols are used in CA issues." (Davenport, 1968, p. 37).

4.59 "The data contained in the augmented catalog are basically alphanumeric. Of particular consequence to both the display console design and the entire computer-based library is the large number of alphanumeric symbols that is required. The set of 128 USASCII standard symbols is insufficient, and thus must be augmented. Furthermore, provisions for superscripts, subscripts and underlines must be included to properly display to users in forms with which they are familiar such items as chemical formulas and mathematical equations." (Haring, 1968, p. 36).

4.60 "Filing rules pose a particularly complex problem to the designer of an information system. Unfortunately, the machine has not been built which will sort according to such filing rules as those laid down by the American Library Association. The system designer must choose between an attempt to program these rules into the computer or to employ special control codes on input to permit the citations to be sorted according to the filing rules rather than the normal collating sequence of the computer." (Austin, 1966, p. 244).

4.61 "The earlier work of Opler and Baird in drawing chemical structure diagrams on a computer controlled CRT gave much promise for the future applicability of such devices. . . .

"Use of 2-case print mechanisms on high-speed computer printers for the display of extended chemical character sets has been under joint development by IBM and Chemical Abstracts . . ." (Burger, 1964, p. 2).

"The use of photocomposition equipment to reproduce structural chemical formulas from coded tape is of special interest in the publication of the output of chemists and chemical engineers, but the proposed work would have application to almost all other branches of science where publication of material requiring spatial delineation is necessary." (Kuney, 1963, p. 249).

"Using as a starting point the characters devel

oped by workers at American Cyanamid for the typing of chemical structures, we proposed a font of 50 lines and angles with which we could construct the needed bonds and rings.

"Machine setting of chemical structures was suggested as one of the potentials of the photocomposition work we started in 1958. The development of the chemical typewriter by Jacobus and Feldman at Walter Reed and computerized typesetting techniques by Barnett and others stimulated the development of a test matrix disc for the Photon." (Kuney and Lazorchak, 1964, p. 303).

"With the cooperation of the workers at Walter Reed, we are planning to encode structures using the Army chemical typewriter and process this input via computer to get a tape which will operate the Photon for the setting of chemical structures." (Kuney and Lazorchak, 1964, p. 305).

4.62 "The ultimate challenge to calligraphy for computers is the imitation of brush strokes in Chinese and Japanese characters. An investigation has been made to determine the feasibility of digitalization of the Japanese characters. The results... have been used for the preparation of an abstract of a Naval Weapons Laboratory report in Japanese as well as in French and German." (Hershey, 1967, p. 15).

4.63 "An application of the GDP, dubbed 'Type-A-Circuit', has been developed by L. Mailloux and his colleagues. A contrived alphabet or character set may be assembled into a pattern to create a mask for printed circuit etching. Horizontal, vertical, and diagonal segments, bends, mounting pads, and sockets or transistors and several types of integrated circuits have been made a part of this character set...

"The processing program also contains plugboard prongs which are superimposed over the image generated by the Type-A-Circuit specifications. In use, the designer prepares the string of 'letters' which specify the elements of the Type-ACircuit character set in juxtaposition with one another, thus forming leads, bends, pads, and sockets. This specification is prepared with the aid of a rough sketch drawn on a specially prepared form. The graphical output consists of a finished negative which may be used directly for photoetching of a copper clad board. The time required to prepare artwork for etched circuit boards has been greatly reduced with the Type-A-Circuit system." (Potter and Axelrod, 1968, p. 4).

5.1 "The most important need is for a design philosophy that aims at the design of total information processing systems, and that will eliminate the mostly artificial distinction between hardware systems and software systems. We need a continuing development of the trend toward com

bined hardware-software programming." (Rosen, 1968, p. 1446).

"Since, ultimately, the only computer system of any significance to the outside world is the system composed of hardware plus software, one cannot claim to have truly designed a computer