Cmpnr. E&c. Vol. 8. No. 4. pp. 323333, 1984 Printed in Great Britain

0360-1315/$4 93.00 + 0.00 Pergamon Press Ltd

CAL TECHNOLOGY: DECADE PAST, DECADE PRESENT

J. W. BRAHAN

National Research Council of Canada, Ottawa, Ontario, Canada KIA OR8

INTRODUCTION

At the beginning of the seventies, a significant interest had already been aroused in Computer- Assisted Learning (CAL). While there were many centres of activity, operating costs were high and most, if not all of the activity was experimental with little ongoing operational applications of the results. It was in this setting that the National Research Council (NRC) began a collaborative project in CAL that, over the next 12 years was to involve the active participation of many organizations throughout Canada. Towards the end of the decade, computer technology had advanced sufficiently that CAL was accepted as economically viable in many applications. Today, availability of low-cost mini and microcomputer systems has extended the range of economical CAL many-fold. This paper reviews the progress of CAL technology to date with a particular focus on the NRC-CAL project and projects some of the developments of CAL to be expected during the rest of the present decade.

CAL TECHNOLOGY IN t970

In 1970, following a preliminary feasibility study, the National Research Council (NRC) embarked on a cooperative program of research and development in Computer-Assisted Learning (CAL). At the time, CAL was still very much in the laboratory stage. While early experiments had clearly demonstrated the potential of the computer for achieving striking improvements in rate and/or quality of learning, few operational applications of these experimental results had been implemented, largely due to the high costs and the difficulty in justifying these costs relative to the benefits achieved.

The state-of-the-art of CAL technology at the beginning of the seventies was represented by a commercial offering by IBM, the IBM- 1500 system [I], the PLATO-III System at the University of Illinois [2] and a system based on a PDF-10 at Stanford University [3]. The IBM-1500 system provided for up to 32 multi-media terminals located local to the central processor. Each student station consisted of a video display unit incorporating character graphics and input by means of keyboard and light-pen. Also available as options for the terminal were an image projector based on a 16 mm film strip providing up to 1024 slide images and an audio tape unit with access to 1024 pre-recorded audio messages. Coursewriter- was the authoring language for courseware devel- opment. An IBM-1500 System was installed at the University of Alberta in 1967 and operated in the Division of Educational Research Services until 1980. A second system was installed in Canada for a shorter period in Quebec City at the Laboratoire de Pedagogic Informatique of the Quebec Ministry of Education, where it was operated as part of an experimental project from 1971 to 1973. A move by IBM away from the specialized system for CAL towards integration of their CAL product into the general-purpose computer facility was indicated by the availability of and increasing emphasis on the Coursewriter-III language and supporting software for the IBM System-360.

The PLATO-III system at the University of Illinois was a second example of a specialized system for CAL incorporating multi-media terminals, but differed from the IBM-1500 in that it placed more emphasis on computer-generated graphics, communications and remote location of termi- nals. The PLATO-III student terminal consisted of a special keyset and a television monitor that provided for the superposition of photographic images, electronically selected from a central storage bank, computer-generated graphics and text, with particular emphasis on the ability to

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selectively erase the computer-generated information on the student screen. The PLATO-III system required wide bandwidth video communication facilities, being dependent on centrally located storage for photographic and computer generated images but work was under way on the design of the PLATO-IV system which eliminated this requirement through provision of a microfiche projector in the student terminal. Development of the Plasma Display Panel that provided for display and storage of graphic information and was to be a fundamental component in the design of the PLATO-IV system was also well advanced. By mid-1970, there had been 720 hours of instructional material developed on the PLATO system and over 100,000 h of student use.

At Stanford University, the work on CAL was based primarily on the use of general-purpose computing equipment (with some special system software) and standard communication facilities to permit use of CAL for in-school experiments at various locations in the U.S. Student terminals were Model-33 Teletypewriters with slightly modified keyboards and were connected to a Digital Equipment Corporation computer at Stanford. The initial computer was a PDP-1 which was upgraded to a PDP-IO at the beginning of the seventies. Digitized audio provided an additional output facility that had been used in “dial-a-drill” experiments in which the user’s telephone served as a computer terminal. A second major program had been undertaken by the Stanford group with an IBM- 1500 System to investigate the feasibility of using the computer for teaching mathematics and reading in the elementary school program.

A fourth project representative of the state-of-the-art of CAL in 1970, though it was not as advanced operationally, is the Mitre Corporation’s TICCET project [4] {Time Shared Interactive computer-Controlled Educational Television). In 1970, the initial design had just been completed of a system using minicomputers, digital audio and video-disc storage techniques to deliver multi-media CAL to a cluster of up to 128 television-based student terminals. Course authoring was intended to be carried out on a facility separate from the delivery system. The pilot TICCET system was assembled using an IBM 360/50 computer and provided good resolution graphics and two-level grey scale television pictures. The design of the proposed operational system was based on the use of minicomputers for multiplexing and processing tasks with annual costs projected to be between $730 and $1200 per student terminal. By 1972, the design had been modified to incorporate colour TV display terminals and semi-conductor video refresh memory, and the name changed slightly to “TICCIT” (Time-share, Interactive, Computer-Controlled Information Tele- vision) [5].

At the beginning of the seventies, commercially available computer technology was based primarily on discrete components with some small scale integration. Effective time-sharing was available from a number of suppliers and there was a strong interest in computer networking. The ferrite core was the main building block of computer memories with a cycle time of the order of one microsecond. At the beginning of 1970, however, there were predictions that 1970 would be the year that plated wire and semiconductor memory would invade many of the memory system markets that were controlled by the ferrite core systems. While plated wire memories attracted some attention during the early part of the seventies, it was the semiconductor memory that, by the end of the decade, had replaced the ferrite core as the basic component of main computer memory. In 1970 large scale integration was only just coming out of the laboratory and the number of active elements per chip was of the order of 4000. Memory chips of lK-bit capacity were available and semiconductor memory systems using these chips had been constructed with packing densities of about two million bits per ft3. There was, however, the promise of much more to come. The ful~llment of this promise began in 1971, when Intel introduced an integrated CPU, the 4004, one of a family of four integrated circuits that made up the first microcomputer system.

THE NRC-CAL PROGRAM

At the time that NRC embarked on the collaborative program of research and development in CAL, there was a clear indication of the potential for CAL and while costs of the technology were still high, they could be seen to be decreasing such that CAL would soon be economically viable in a growing number of areas. Nevertheless, the cost of the facility required to carry out CAL research and development was still beyond the reach of many centres. Hence two areas of primary concern in planning the NRC-CAL program were the provision for participation without too great

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an initial capital expenditure by local research centres and achievement of a certain compatibility of software in various parts of the country in order to economize on the use of limited resources

available for courseware development. To make effective use of existing resources and avoid duplication, there was a general division

of responsibilities within the cooperative program. The research group at NRC was concerned primarily with the development of CAL technology. In the participating external organizations, the main concern was with the application of the technology to the development and delivery of the educational content and it was the end user requirements as defined by this activity that guided the development of the technology. In terms of resource sharing, NRC provided, at no cost to the participating organization, services in system programming, special equipment design and com- puter time.

The work at NRC fell into three distinct but related areas. The Network Project was the focus of interaction with the participating organizations and involved a variety of application areas. The Hardware-Software Project focused primarily on multi-media student stations and commu- nications. The National Author Language Project grew out of work initiated by the Associate Committee on Instructional Technology and has resulted in the development of the NATAL-CAL system.

NETWORK PROJECT

Late in 1969, NRC acquired a PDP-10 Computer System to serve as the basis of a central facility in support of the CAL research program that was to involve active participation by twenty organizations throughout Canada in a variety of projects over the next decade and beyond. The initial installation was very limited, consisting of 32K words of core memory, 500K of fixed-head disc memory and 8 communications ports, but provided adequately for the development of the software required during the initial stage of the project. As the project progressed, the computer facility was expanded in response to requirements for CAL system software, courseware and

gathering of data generated by field testing. By 1978, the system incorporated 224K words (1 megabyte) of core memory, 65M words of removeable disc memory and 24 communication ports.

The CAL research network offered a number of advantages. Through the network, users were provided access to a large system for their project without the corresponding capital investment. Users could actively participate in system development and evaluation. Content and techniques developed on the network provided a resource available to all participants. Finally, the use of the network promoted intercommunication between research groups with the common interest in CAL.

The first outside organization to be linked to the NRC-CAL computer was the Ontario Institute for Studies in Education (OISE). A single teletype terminal at OISE in Toronto connected to the NRC computer in early 1970 was soon replaced with a multi-terminal link used in a project undertaken by OISE in cooperation with the Ontario Colleges of Applied Arts and Technology [6]. The CAL technology developed in support of this project came from both OISE and NRC and the project provides a good example of the effectiveness of resource sharing made possible through the network. At NRC, a specialized operating system for CAL applications was under development. This system, called “OPSYS” [7], was adapted to provide multiple user access, data recording capabilities and general system support for the single-user version of the CAN course authoring language interpreter that had been developed by OISE. Compatible software was developed by OISE for their TSS-8 computer in Toronto to permit a multiplexed connection to the NRC computer by student terminals connected into the OISE computer. Through this jointly developed software, a CAL delivery system that made economical use of computer and commu- nications facilities was put into operation to support extensive field trials in the Community Colleges throughout Ontario.

A more general multiple user access program called “MLINSR”, was developed by NRC in collaboration with College Edouard Montpetit and Universite du Quebec a Montreal as part of a LOGO project undertaken by the College on the NRC-CAL network. The MLINSR program was later adapted for use with OPSYS-CAN in the OISE project and in a project with the

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Canadian Forces initially using the OPSYS-CAN system and subsequently the NATAL-CAL system.

During the early years of operation of the CAL network, digital communication lines were not available and all data communization with the CAL computer was through use of analog telephone lines. While the error rate on these lines was not excessive for single terminal text communication, it could play havoc with multi-media terminals and with text display terminals multiplexed on a single line if the error occurred in the address portion of a message. Thus it became necessary to develop a system of error detection and correction (through retransmission). This system was accessibte through MLINSR and could be used by experimental multi-media terminals as well as terminals sharing a common communization line through a line-concentrator computer. When digital communications facilities became available from the common carriers, the need for this facility was greatly reduced.

The LOGO system that had been brought to the Network by the College Edouard Montpetit project was subsequently used in the York Interactive Music Project undertaken by York University on the NRC system. The LOGO implementation was also supplied, with enhancements introduced as a result of requirements defined during the two projects, to several other PDP-10 installations for their own LOGO projects. One of the enhancements that was produced by the College Edouard Montpetit project was a French Language version of the LOGO system.

System software that was developed on the network for one project was usually applicable to others and added value to the facility as a whole. Projects on the NRC-CAL network were intended to cover a broad range of applications and attempts were made to avoid overlap and duplication. Thus while there was some sharing of user courseware, this was not as extensive as the sharing of system software. An example of effective courseware sharing is provided by an initial experiment of the Canadian Forces in which they made use of the mathematics materials developed during the OISE project, to introduce instructors and students to the concepts of CAL [8].

From its limited beginning in 1970, until its termination in 1982, the NRC-CAL network supported a variety of projects at locations throughout Canada as indicated in the Appendix and provided clear demonstration of the benefits to be achieved from such a cooperative research

facility.

HARDWARE-SOFTWARE PROJECT

Activities of the Hardware-Software Development Project were primarily associated with the development of terminal facilities and communication support software to meet the special requirements of CAL. Of particular importance was the multi-media student terminal. The IBM-1500 System and the PLATO System had demonstrated the requirement for such facilities in many CAL applications. However, both systems incorporated the special CAL terminal as an integral part of the system structure and provided little flexibility in terminal variations. There are many CAL applications in which nothing is required beyond the keyboard-driven alphanumeric display terminal and the expense of a more complex terminal cannot be justified. In other applications, a full multi-media terminal is a necessity and there may be a requirement for special devices to be attached to the terminal. With this range of requirements in mind, the terminal development work at NRC emphasized conformity to applicable technological standards so that the resulting terminal would not be constrained to use with one specialized CAL system and components developed for other applications of computer/communications technology could be readily incorporated in the CAL facility as required.

Within this laboratory project, a number of specialized terminal devices were developed, aimed at providing greater flexibility in the presentation of information to the student and the acceptance of responses. In 1970, work was well advanced on the development of a touch-sensitive overlay [9] that could be used as a computer input unit in conjunction with a variety of display devices. Ultrasonic surface waves on a glass plate, transmitted from two orthogonal edges were used to locate the position of a passive stylus such as the finger. Each time the surface of the glass was touched, coordinates of the location were transmitted to the computer. Since the tablet was transparent, it could be placed over a variety of display devices, such as a television or slide projector screen or even a printed card. Through the interpretation of the received coordinates by

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the computer, the touch input was directly and simply related to the information displayed on the

user’s screen. Computer-controlled audio was the subject of several experimental activities [lo]. A random

access audio tape unit was developed that made use of a conventional reel-to-reel tape recorder, providing a large capacity store at low cost. To provide for much faster access to prerecorded audio messages, a magnetic disc unit was developed that provided for storage of 30 min of audio information with a maximum access time for any given message of 1 s. In 1973, a Votrax VS5 voice synthesizer was acquired at a cost of approx. $4000. At the time, this unit was considered a major breakthrough, offering voice synthesis at about one-tenth the cost of previously available synthesizers. Today, voice synthesizer chips are available for $10 and complete units for less than $200. Software was developed for the voice synthesizer to assemble synthetic speech by specifying the phonemes with appropriate stress on each. Software was also produced that provided for automatic conversion from typed or previously stored text to the spoken word. The conversion was achieved by applying about 200 rules and a dictionary of exceptions to the stored text. While the resulting speech was lacking in quality, it did make stored text accessible in audible form.

The various display and input devices developed under the project were incorporated in an

experimental multi-media terminal that was tested with a number of demonstration programs and also used in support of experimental research on learning difficulties conducted by Carleton University and the Rideau Regional Hospital School [1 11. The experimental student terminal was also used as the basis for development of commercial terminals that were used in Air Canada’s flight-crew training program and by the Canadian Forces in electronics technician training. A portable multi-media terminal developed as a follow-on to the commercial terminals has received extensive use in a project to investigate computer-based learning-ability testing undertaken by the Childrens’ Hospital of Eastern Ontario [ 121.

The specialized equipment developed for CAL applications in the early part of the project, tended to reflect a “hardware-oriented” approach. Use was made of available digital integrated circuits but the approach was based essentially on an extension of design techniques using discrete components. This resulted in production of experimental models at low component cost, but it was expensive in terms of development time and difficult to accommodate changes and often, by the time the experimental model was constructed and tested, significant improvements could have been made through the use of newer component technology that had become available during the development period. The evolution of micro-electronics in the early seventies made it economically practical to shift the development of experimental models to a software oriented approach. Using an Alpha-16 minicomputer as the controller, an experimental terminal was developed to provide for a student workstation enriched with a variety of display-response facilities [13]. The initial display device was the Plasma Display Panel used in the University of Illinois PLATO Project. The panel provided 512 x 512 directly addressable points on a screen 8.5 in’. With reduction in the cost of semiconductor memory, it was later practical to substitute for the Plasma Display Panel, a television-compatible display with selectable resolution of 512 x 512 or 640 x 480 (corresponding to the aspect ratio of the standard television screen).

In 1975, the era of the low-cost microcomputer began with the announcement by Micro Instrumentation and Telemetry Systems Inc. (MITS) of the Altair 8800, which was based on the Intel 8080 microprocessor chip. It was offered in kit form and introduced in the January issue of

Popular Electronics, aimed at the hobbyist market [ 141. For approx. $1000, a hardware system kit with 4K bytes of memory and a communications interface for a teletype or similar text display terminal could be obtained. Software, however, was essentially non-existent. The Altair was soon joined by similar and more sophisticated machines from other sources. The Apple computer came on the scene in 1976, with the Apple-II introduced the following year. By 1979, Apple sales had grown to $75 million annually and by 1982, had reached $664 million.

The microprocessor had its impact on CAL in two ways. It became possible for the CAL user to acquire a microcomputer within his price range that could be used independently of a large mainframe computer. However, while such systems were capable of delivery of instructional materials, during the early years of the microcomputer, available system software was usually limited to a rudimentary editor, a restricted operating system and a subset of the BASIC language. Courseware and courseware development tools for the microcomputer system were essentially

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nonexistent. There was some improvement in the situation by the beginning of the eighties but the “micro-CAL” user still did not have access to equivalent courseware development facilities that had been provided by the IBM-1500 and the PLATO systems ten years previously. With the development facilities available, CAL materials produced on these micro-systems tended to be very limited in scope. In the minds of many CAL experimenters, the microcomputer had set back the development of CAL by 5 years or more.

As a system component, the impact of the micro was quite dilferent, in that it did not place the same added burden of content development on the user. Specialized systems could be developed that operated independently of external resources and satisfied the users need as a “turnkey system”. An example from the NRC-CAL project is provided by the development of commu- nication aids for the non-speaking handicapped using Bliss-Symbols and speech synthesis techniques to provide audio reinforcement. The development and initial assessment of the speech synthesizer system was carried out in collaboration with the NRC Medical Engineering Section at the Ottawa Crippled Children’s Treatment Centre, using a telephone link to the NRC-CAL computer. The preliminary study [ 151 demonstrated the effectiveness of the speech synthesis system at holding the children’s attention and giving them independence to work on their own and at their own rate. This subsequently led to the development of a self-contained microcomputer based system for use in the classroom.

The microprocessor has also had a significant impact as a component of the terminal equipment used in CAL and other applications. So-called “intelligent” terminals have become available at moderate cost, providing for display of text, graphics. colour, and user definition of special functions. The Telidon terminal, developed for the mass videotex market, provided good colour graphics at low cost with the promise of much lower cost as the videotex market developed. Within the NRC-CAL project, much use was made of the microprocessor as a programmable controller to permit the assembly of a variety of multi-media terminal configurations. In this way, touch panels and digitizer tablets were added to Telidon decoders to provide a low-cost interactive graphics terminal for CAL development and delivery. Provision was also made for use of slide projectors, video-disc players and audio units to be connected and operated through the programmable controller.

The use of specialized terminals uniquely for CAL applications had proven to be a costly approach during the seventies and the economies of scale that had been predicted were slow in coming. The original PLATO project prediction that the cost of the Plasma Display Terminal would fall to $1800 [16] with volume production had not as yet been achieved. However, the incorporation of programmable microprocessors in computer terminals and their application at terminal controllers opened the possibility of customizing terminals for the CAL application while at the same time retaining the cost advantage of terminals produced for mass markets, such as videotex. In keeping with this philosophy, the activity within the NRC-CAL Hardware-Software Project shifted from primarily hardware design and construction in the early seventies to software design and system integration by the beginning of the eighties.

NATIONAL AUTHOR LANGUAGE PROJECT

In 1971, the NRC Associate Committee on Instructional Technology convened a Working Panel with the objective of defining the characteristics of a course-authoring language to meet user requirements across the broad range of applications that were foreseen for CAL. The Panel drew its members from centres across Canada and represented experience with specialized systems such as the IBM-1500 and PLATO as well as general-purpose systems that had been used for CAL at that time. The report of the Panel was presented in 1972 and took the form of a functional specification [17]. This document subsequently formed the basis of a contract with IBM Canada for the development of a detailed design specification, delivered to NRC in 1974 [18]. Later that year, the National Author Language Project was initiated within the laboratory to implement and evaluate the language. which had been given the name “NATAL-74”. In early 1977, a somewhat shaky prototype was operating and preliminary user testing began. By 1979, a reasonably stable prototype had been achieved and tested in a variety of applications. The introduction of colour graphics to the system in 1979 through the Telidon terminal. identified some weaknesses in the

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NATAL graphics facilities. The specification was subsequently revised to correct this deficiency, taking the ACM Core Language recommendation as a guide to the definition of commonly accepted graphics practice [ 191.

In 1979, a technology transfer contract was initiated with Honeywell and by 1982, imple- mentations of NATAL-II [20] were completed on three computers, the DECsystem-10, the Honeywell Level-6 and the IBM MVS System. During this period, user testing continued on the NRC DEC-10 installation and also on a Honeywell Level-6 installed at Canadian Forces Base Trenton in 1981. Within the NRC laboratory, work was also underway on the study of a microcomputer implementation of NATAL [21].

In some aspects, the early work on NATAL was predicted on major advances in cost- performence of computer hardware. The initial implementation was very demanding of computer resources for both installation of the system and execution of user programs. However, no attempt was made to economize in this respect in the development of the prototype by reducing the facilities as defined in the NATAL specification. It was felt that functional changes should be introduced in response and in accord with application requirements. Costs of computer memory and

processing power were seen to be decreasing while the cost of human effort was increasing. Thus the potential productivity improvement offered through the facilities incorporated in the language was judged to offset the high cost of computer resources. With the advances in computer technology to date, that approach has been justified.

CAL TECHNOLOGY IN THE EIGHTIES

At the beginning of the eighties, commercially offered CAL technology can be categorized in two main classes--systems associated with large mainframe computers and those based on micro- computers. In the first category, there are systems such as Control Data’s PLATO that had evolved

from the work at the University of Illinois, IBM’s Interactive Instructional System, based on that company’s earlier Coursewriter systems, and Hazletine’s TICCIT system, which had its origins in the Mitre Corporation’s work and courseware development techniques from Brigham Young University. While installation of these systems require a substantial capital investment in computer facilities, examples of cost effective applications of all three can be found, particularly in areas related to industrial training [22]. Total market penetration to date has, however, been limited and in the primary and secondary school markets, has been essentially nil. Microcomputer systems have, on the other hand, attracted the attention of the schools as both a subject of instruction- “computer literacy” and as a vehicle for delivering instruction-CAL. Within industry, there is also a growing interest in the use of the microcomputer for training. Thus, while both the large computer system and the micro will have a significant role to play in CAL during the eighties, the development of CAL technology will for the most part be determined by the evolution of the microcomputer.

A substantial market had developed for the 8-bit microcomputer by the beginning of the eighties and the introduction of machines such as the Apple-II, Pet, TRS-80 and others into the schools was underway. The arrival of the sixteen-bit machine was marked by the entry of IBM into this market in 198 1 with its PC that achieved sales of $500 million in 1982. Today 16-bit processors are becoming commonplace in microcomputer systems and the 32-bit processor has made its appearance. The 32-bit microcomputer introduced by Hewlett-Packard in 1983 has a processor with 450,000 elements on a single chip and we can expect to see higher densities as the decade progresses. Memory chips containing 64K bits were available in quantity production and incorporated in large computer systems by late 1981. The 256K bit chip is now in production and we can expect extensive incorporation of these chips in end products during 1984. IBM has just recently announced the development of a 512K bit chip and by the end of the decade, we can conservatively expect to see the megabit memory chip in volume production. As the functionality of the processor and associated chips increases, the cost of incorporating them in the end system decreases. Thus it is reasonable to project that the more powerful hardware systems will cost no more and possibly less than the 8-bit systems of the beginning of the decade.

Peripheral storage is of particular importance in most CAL applications for instructional materials, student records, performance recording and other administrative needs. The intro-

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duction of the microcomputer in the mid-seventies was accompanied by the use of cassette tape recorders providing limited access to secondary storage of programs and data. More interactive use of secondary storage was permitted with the introduction of the floppy-disc and the mini-floppy that were soon incorporated as integral components of many microcomputer systems, providing as much as a megabyte of on-line storage. However, many of the CAL courses produced on the large systems during the seventies, required 2 megabytes and more of storage space. With the introduction of the Winchester disc, microcomputer systems are now available incorporating 10 megabytes and more of rapid access disc storage at moderate cost. Thus, the hardware facilities of the microcomputer are now adequate for its role as a delivery vehicle to satisfy the requirements of most CAL applications. Software is another matter, however.

SOFTWARE AND COURSEWARE

During the seventies, the variety of CAL materials extended from complete “courses”, providing 50 h or more of on-line instruction to short packages involving student contact time of a few hours or less. These packages were in general, intended as adjunct materials to be used in the “traditional” instructional environment. The majority of courseware developed during the seventies was in this latter category, reflecting perceived user needs, difficulties of integrating CAL into the existing structure as well as the facilities available for development and delivery. The development of long complete courses was, for the most part, limited to the large CAL systems that provided the necessary program development data gathering and analysis facilities. The introduction of the microcomputer tended to increase the emphasis on small package courseware.

However, system implementation languages (C, BCPL) and operating systems (UNIX) have now crossed the macro-microcomputer boundary and the microcomputer is being furnished with increased facilities to support courseware development as well as with greatly improved access to materials developed on the large systems. Thus as processing, storage, and system software facilities available to the microcomputer increase, the technology is ceasing to be a significant factor in determination of courseware complexity.

In common with other software, the development of courseware is labour intensive. Estimates of the effort required to produce 1 h of CAL instructional material range from 30 to 600 h. While a significant reduction in programming effort has been achieved through the development and use of high-level languages such as NATAL, programming skills are still required. The use of “templates” reduces the need for programming skills but greatly reduces the options available to the course developer. In recent years, attention has been drawn to the use of program generators as a tool to increase programmer productivity [23]. The program generator accepts user input in a format appropriate for the particular application and creates a source code program that can be combined with other source code modules, can be modified manually and can be compiled or interpreted in the same way as a hand-written program. Through the use of specialized “editor” programs that can utilize a variety of input devices, the courseware developer can implement a significant part of his design without programming in the conventional sense but at the same time maintain compatibility with materials produced through conventional programming. In this way, the user is provided with a software tool that offers the promise of productivity improvement that the integrated circuit brought to hardware design. Extensive development remains before program generators for CAL reach this level of sophistication, but by the end of the decade, the program generator can be expected to be a major factor in courseware development.

Most current CAL applications of microcomputers incorporate little in the way of a registration facility, performance monitoring, class reporting system and other aspects of the instructional management function. Little is provided to support the access to the wide range of external information and development facilities that is supported inherently as part of the time-shared computer system. While these facilities can be incorporated in some of the multi-user micro- computer systems that are now appearing on the market, this is simply a low-cost version of the time-shared minicomputer systems that were available and used for CAL in the early to mid-seventies. The real power of the microcomputer in the CAL system is the flexibility that it permits in the dedication of computing functions. Through the use of local networking techniques, the user can be provided with dedicated computer power that provides consistent performance in

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the CAL delivery mode, not a performance that varies according to the number of users on the network; that provides access to libraries of instructional materials accessible in a mode entirely transparent to the user; that provides for the instructional management function in a separate dedicated processor; and that provides access to larger computer systems for course creation, data analysis and special services. Such CAL systems can be implemented entirely local to an institution or they may be connected through public networks. The use of network techniques will be a major factor in the development of CAL systems and we can anticipate facilities to support this mode of operation being incorporated in Videotex and Cable TV systems by the end of the decade.

Many of the techniques of artificial intelligence that were developed on very large machines during the seventies can now be re-examined for their applicability to CAL. Expert systems have been applied effectively in areas such as medical diagnosis and uranium prospecting. These

applications in themselves offer interesting possibilities as instructional resources. In addition, the potential exists for using these same techniques to relate the student’s needs to the instructional resources available for specific skills development. Additional opportunities are offered in the area of natural language processing to improve the interface between the user (student, teacher, course author) and the machine. The reduced costs and increasing capacity of available computing systems brings many of these techniques within the range of economic practicality for CAL.

CONCLUSION

During the past decade, the effectiveness of CAL was clearly demonstrated in a variety of modes and applications but the high cost of systems and content has restricted the extent of these applications. The appearance of the microcomputer significantly reduced the cost of hardware required to support CAL and during the present decade, we can anticipate even lower hardware costs accompanied by higher performance along with the development of system software and courseware creation facilities that will make CAL affordable in the schools and mass market. CAL technology will continue to evolve during the present decade, but the experience of the seventies shows that cost-effective CAL technology will be built on the technology developed for other markets. Videotex offers the potential of an important instructional resource but Videotex technology was not developed in response to the instructional requirement. The microcomputer is fundamental to current CAL technology and its future evolution but the development of the low cost micro was not driven by the CAL requirement. Other technologies such as videodisc, voice synthesis, etc. developed for the business and consumer markets will have a major impact on CAL. Thus the development of CAL technology to be of maximum effect must be sufficiently flexible to incorporate these new technologies as they become available. Dependence of the CAL system on highly specialized equipment will greatly restrict the scope of its applicability. Even within the school the use of the microcomputer covers a wide range of requirements and the CAL system cannot add excessively to the requirement without becoming too costly.

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Conference, Vol. 35, pp. 18-20 (1969). 10. Kenney J. R. Rapid access magnetic audio recording systems. Can. Elec. Engng J. 6, 2429 (1981).

332 J. W. BRAHAN

11. Knights R. M., Richardson D. H. and McNarry L. R., Automated vs clinical administration of the peabody picture

vocabulary test and the coloured progressive matrices. Am. J. Mew. D#. 78, 223-225 (1973). 12. Pressman D. E., Cunningham S. J., Pressman I. S., Brahan J. W. and Henneker W. H., Computer evaluation of

language skills in children. Report ERB 945. National Research Council of Canada, Ottawa (1982). 13. Hlady A. M., Brahan J. W., Gratton G. and Humphries J., A terminal development facility for computer-aided

learning. Proceedings qf the Second Canadian Svmposium on Instructional Technology, pp. 586-598. Quebec (1976).

14. Roberts H. E. and Yates W., Altair 880Gthe most powerful minicomputer project ever presented-can be built for under $400. Popul. Electron. 7, 33-38 (1975).

15. Nelson P. J., Cossalter J. G., Charbonneau J. R., Orpana F. P., Cot6 C. and Warrick H. A., Speech synthesis for non-verbal children-a progress report. Proceedings of‘ the Cot@rence on Systems and Devices .for the Disabled, pp. 153-l 56. Seattle (1977).

16. Kearsley G. P., The costs of CAI: a matter of assumptions. AEDS JI 10, 105 (1977). 17. ACIT Working Panel. A functional specification for a programming language for computer-aided learning applications.

Report NRC-13659, Associate Committee on Instructional Technology, National Research Council (1972). 18. Westrom M. L., National author language NATAL-74 specification manual. Report NRC-14245, Associate Committee

on Instructional Technology, National Research Council (1974). 19. Orchard R. A., Implementing the GSPC core language recommendations in an existing CAL language, NATAL.

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NATAL. Compur. Educ. 8, 361-370 (1984). 22. Brahan J. W. L’Enseignement assiste par ordinateur et la formation professionnelle. Acles des journbes ANTEM pp.

36-45. Paris (1983). 23. Roth R. L. Program generators and their effect on programmer productivity. Proceedings of the National Computer

Conference, pp. 351-358. Houston, TX (1982).

CAL technology

APPENDIX

NRC-CAL Network Project Participants 1970-1982

Institution Project

333

The Ontario Institute for studies in Educastion (OISE) Toronto, Ontario University of Calgary Calgary, Alberta

University of New Brunswick Fredericton, N.B. McMaster University Hamilton, Ontario College Edouard Montpetit Longueuil, Quebec Universite de Montreal Montreal, Quebec Carleton University Ottawa, Ontario Algonquin College Ottawa, Ontario Canadian Forces School of Communications and Electronics Engineering Kingston, Ontario York University Toronto, Ontario Public Service Commission Ottawa, Ontario Crippled Children’s treatment Centre Ottawa, Ontario Children’s Hospital of Eastern Ontario Ottawa, Ontario University of British Columbia Vancouver, B.C. Canadian Forces

Training Systems Headquarters Trenton, Ontario 426 Transport Training Squadron Trenton, Ontario Fleet School Halifax, Nova Scotia

University of Victoria Victoria, B.C. University of Western Ontario London, Ontario University of Waterloo Waterloo, Ontario Department of Communications Hydro-Quebec Montreal, Quebec NRC Industrial Development Office Ottawa, Ontario

Community College Mathematics

CAL for the Developmentally Handicapped-Basic Reading and Arithmetic Skills CAL Review Lessons for High School Physics CAL in a First-Year Chemistry Learning Resource Centre Logo Applications

Modelling of the Learning Process Automated Testing of Learning Abilities English as a First Language

Basic Mathematics and Basic Electronics Trades Training

Interactive Music Project

French as a Second Language

Communication Aids For the Handicapped Computerized Auditory Skills Testing Arithmetic Skills Testing and Remedial Instruction Trades Training:

Aircraft Maintenance Computer Fundamentals

English Grammar, Logic

Audio Tactile Braille Learning System English Literature

NATAL-Telidon CAL in Management Information and Informatics Training Staff Training on NRC Programs and Services