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Two papers are included in this report. "Control and Feedback in the Environment of a Computer Tutor" investigates some control and feedback properties of a tutorial environment comprised of a student, his computer tutor, and the designer of the computer tutor. Three classes of computer tutor are described: rigid, generative, and knowledgeable. These classes are distinguished by an increase of the interactions among tutor and student and a decrease of the control of the tutor over the tutorial environment. Full partnership between tutor and student could be achieved with the help of programs that understand natural language. "Review in CAI: The Problem and an Implemented Solution" discusses review of material, which is made necessary by human memory loss. The computer tutor that incorporates review is built around performance programs that know what the student is to learn, generator programs that generate problems the student must learn to solve, and extensive diagnostic programs that guide the tutor in his interaction with the student. Borrowing compiler-writing techniques, a multi-level system for review has been implemented that avoids extra coding and repetition of material in identical form. (Author/JK)

The field of computer applications in education, characterized by continuous change in technology and nomenclature, is documented by diverse information sources. This paper names methods of organizing information on computer-based instructional systems and lists sources under literature surveys and reviews, conferences and symposia (1965-68, U.S.A.), publishers, and professional organizations. Interactive uses of computers for instruction include drill strategy, author-controlled tutorial, and "dialogue" tutorial; simulation and gaming; information handling, computation and display (scholarly aids); computer aids for instructional management; and computer-based tools for the author and researcher. The variety of lessons, systems, and languages for computer-based instruction depends on instructional objectives and on records of student performance. (TI)

In spite of the lack of specific and properly defined goals and plans about the use of computers for their development, some non-industrialized countries have made substantial advances in this computer usage. In these countries, the number of computers installed ranges from zero to roughly 1 per 200,000 inhabitants. The distribution of these systems among areas of application (business and commercial engineering and scientific, education and training, military and defense), is fairly similar to that observed in advanced countries. The majority of the developing countries have installed computers of varying capacities in some of their higher learning institutions, which is acting as a triggering factor for more and better computer installations. The upper bracket of the industrial, commercial and services enterprises of a substantial part of these countries have installed computer systems. The use of automatic data processing systems has initiated a revolution in management attitudes and techniques. There is, in almost all of the developing countries a strong tendency to increase the use of computers in government operations. (Author)

A simple linear model is constructed for production, use and recycling of various paper and related products. This model is used to estimate the maximum feasible recycling rate given the current state of pulp and paper technology. Parametric linear programming is used to investigate the effect of the efficiency of collecting, sorting and transporting waste paper on the fraction recycled.

Because of the complexity of operation of a paper machine, a simulation of operation would provide three avenues through which better startup and operation could be obtained: (1) engineering evaluation, (2) operator training, and (3) control-program evaluation. Prior to the startup of a new high-speed paper machine, a simulation of the stock system where the suspended fibers are formed into a sheet of paper was undertaken. Basic information on the steady-state and dynamic be havior of such a system was obtained on a highly instru mented paper machine having components similar to those of the new machine. The system was analyzed one component at a time to fit available theoretical equations with minor modifications. This allowed reasonable extrap olation and reassembly of the system to describe the new machine. An important factor in describing such a system was the transport lag in the pipelines. This facet of the simulation was accomplished with prewired Padé approximations of these lags. A second important characteristic in describing a paper machine in real time is the long time-constants involved in the rates of change. These may run as long as 10 minutes. A replica of the main control panels was constructed for use as a training aid for the operating crews of the new machine. The panels were programmed on the computer to respond to upsets and grade changes as part of an inten sive training program for the operators. Exploitation of the simulation system is still in progress. It is evident, however, that the smooth startup resulted from careful planning and effective operator training.

This paper presents a technique for simulation of the stock preparation and Fourdrinier dynamics which is flexible, convenient, and detailed enough to allow the user to study physical process modifications and transient response dur ing upsets and "furnish" (fibers with different character istics, fillers, dyes, etc.) changes and to evaluate simplified mathematical models and control schemes. The technique uses digital simulation in a block diagram form, each block of which corresponds to one type of physical unit in the process (e.g., cleaner or tanks). Simu lation of a particular process then involves specification of the particular parameters of each physical unit together with the way in which they are interconnected. Individual components of the furnish may be traced through the whole process. A complete wet-end configuration, including the white water recovery system, is simulated using the technique described in the paper, and typical results obtained during grade changes and disturbances are presented.

Detailed engineering studies on the energy balance profile, which resulted in the establishment of related per area energy costs in the drier section of a hypothetical 300-ton-per-day paper machine, have been converted into an economic model. Based upon these data, a conceptual design on of an equivalent paper machine in which microwave energy is substitued for more con ventional energy in selected areas has been made and an equivalent economic model developed. The comparison of these economic models is then used to demonstrate the relative merits of microwave energy as a useful source of power in paper manufacture. This comparison shows that while capital cost is somewhat increased, the overalI operating cost is decreased. Significant advantages include a more uniform moisture profile, and a substantially shortened paper machine length.

In considering the mathematics program for elementary children, it is important for teachers to examine not only mathematical ideas but also the contexts within which such ideas are used. This usually means an examination of visual aids or tools of learning, since instruction in elementary grades depends upon the concrete to explain the abstract. With this in mind, one such tool that deserves special attention is graph, or squared, paper. Until one looks at the many possible uses of this visual aid, it may be taken for granted, and its applications remain sporadic and disconnected. This article is presented for the purpose of showing that graph paper is an educational device having few peers, especially from the points of view of economy, availability, and ease of use. An ordinary compilation of graph paper uses would be helpful to some degree, but what follows is a sequential development from the primary level through the upper elementary grades.

During the last two decades both the speed and width of paper machines have increased considerably. This has resulted in the adoption of many devices which prior to that time were still looked on with doubt. The increase in width and weight of the rolls of modern newsprint machines has made the removable wet end practically standard. Similarly the increase in speed has only been made possible by the use of the projection slice, suction couch, and press rolls, which are being fitted with success to machines of all types. The shells of suction rolls must be free from blowholes and this has entailed the use of centrifugal castings, and has been the means of developing their technique. A further development is the vacuum-forming paper machine, probably the most revolutionary modification of the Fourdrinier machine yet proposed. The two-wire machine gives a paper free from any wire mark, and recently a wire has been produced which goes some way towards the elimination of the wire mark. Electric drives arc nearly standard on all new machines.

This subject-author index of over 500 papers is intended as a helpful reference tool for those who seek material on the writing, verbal presentation, and publication of technical information, and as a guide to people who have authored such material. Many of the papers listed - especially those given in local society meetings - have not been published. These were included bcause frustration is preferable to total ignorance. To track down an unpublished paper or an author when all else fails, contact the organization that sponsored the meeting at which the paper was given. This index is not necessarily 100% exhaustive; some titles may have been omitted, and some misclassified. Readers are invited to notify the Transactions on EWS of errors or omissions.

This paper describes an attempt to apply linear optimal control theory to computer control of an industrial process. The applicability of the theory is discussed. Particular attention is given to the problem of obtaining a mathematical model of process dynamics and disturbances. Results of actual measurements as well as results from on-line control experience are presented.

Using the principles of elementary dynamics limits are put on the speeds with which a paper transport mechanism which is required to stop at a given character can be expected to work. It is shown that these speeds are nearly four times those so far achieved.

A simple method for the paper tape recording of ESR spectra employing an integrating analog-to-digital converter is described. A method which combines the averaging of several spectra with the smoothing of the resulting mean spectrum is compared with the more conventional practice of using some type of multichannel analyzer or storage register for improving the signal-to-noise ratio in weak spectra.

Summary A multilevel approach to design of a paper machine control system has been presented. The system described includes not only regulating and coordinating control, but also on-line optimizing algorithms. In addition to being a convenient means for organizing the control activity, the multilevel approach provides a framework for organizing the computer software. In actual operating systems, the frequently executed first level programs are core memory resident, while the remaining levels of control reside in a rapid access drum mass storage. The core-drum memory combination is an economical way to implement multilevel control structures.

The device will produce a graph from data in the form of five-track paper tape. The rate of plotting is 20 points per minute at an accuracy of up to one part in 1000. Apart from a standard ten-millivolt potentiometric recorder and tape reader, the device requires 21 transistors, 2 valves and 22 relays.

Analytical difficulties in the analysis of D&C Red No. 21 by column chromatography are overcome by using an ascending paper chromatographic technique, based on that of Graichen, followed by elution of the zones and spectrophotometric determination. Results compare well with those by column chromatography.

A high speed paper tape reader with a maximum speed of 1000 characters per second is described. Relevant principles of construction as well as operating characteristics are given in some detail.

ロ紙を水平空間に保持するopen-strip typeと,著者が自製したガラス板で口紙をはさみ密閉,冷却できるようにしたsandwich typeの2種類のロ紙固定方式にて,ロ紙上物質の移動と泳動電流によるロ紙の発熱,それに伴って生じる電解液の蒸発,ロ紙の毛細管浸透現象による電解液のロ紙中央部に向う流れとの関連について調べた.open-strip typeはロ紙の発熱が著しく,このため泳動方向,泳動像,泳動速度などに安定した結果を得ることが困難であり,また泳動電圧を高くすることは不可能に近い.これに対してsandwich typeではこれらの影響を受けにくく,再現性もえやすいうえに高電圧を加えることが可能であった.それでこのsandwich typeを用いて100V/cm程度の電位こう配にて泳動を実施できるロ紙固定台を試作し,泳動結果の再現性を簡単なグラフにて表現することを試みた.

WITHIN the last twenty years, chromatography has become increasingly important as an analytical tool. The purpose of this article is to review the uses of partition chromatography on paper, which, since its inception four years ago1, has had a wide application and which promises to become as well established as the older forms of chromatography. It should be emphasized, however, that, as mixtures, especially from biological sources, may be very complex, preliminary separations2-5 may often be necessary before paper chromatography can be used to the best possible advantage. For recent developments in all types of chromatography, the reader is referred to a number of articles indicated in footnotes 6–9.

The mere fact that a thing or person has possibilities of good in large amount is no assurance that good will result from the use of that thing or from the individual possessed of that possibility. A superficial study of existing conditions is all that is necessary to ascertain the truth of this statement. The term paper is a valuable instrument in secondary and higher education but is abused and falls far short of its possibilities, because of the clumsy use of a good technique by both teachers and pupils alike. If one was to ask a number of teachers, using this device, what purpose the term paper best served they would probably most frequently receive some form of the following statements: (1) It may be used as a supplement to the regular class work to bring in material that ordinary members will be unable to obtain due to lack of time in class or ability in the pupils; (2) It serves the purpose of offering to better pupils a chance to enrich their school work and in some cases to secure a better grade; (Grades are not what we ought to be after, but it is one thing that many teachers emphasize to the point of causing many of our students to strive for them); (3) It gives a chance for valuable training in organizing valuable data and materials into more accessible and usable form; (4) and, it serves the purpose of giving an opportunity for doing rudimentary research and thus developing skill in solving problems along the line covered by the particular course. The term paper seems to aid in developing several worth-while abilities. Students are required to state a problem in workable form and collect bibliographies covering the topic. They must evaluate, eliminate, and organize the data after they have been found and collected. Many times this takes them into libraries but frequently an experiment must be devised or some accepted form of collecting data that is not available in libraries. Conclusions must be drawn and evaluated upon the basis of adequacy of sampling and reliability of sources. Many times the conclusion is unjustified by the data but the development of the technique is more valuable than the academic and etherial facts collected.

During the past decade, the scope of information science has been evolving into a broader but better defined area of specialization. In this paper several of the definitions of information science which have been suggested by various professional groups are discussed. The educational objectives of information science are identified, and the curricula necessary to achieve these objectives are outlined. The paper discusses the changing nature of the library's role in information science and the impact of computers on the field of information science in general. A list of references is appended. (JY)