annual review
THEODORE J. WILLIAMS
Process Control Industrial impact of maturing computer and automation technology on process control and other aspects o f chemical technology are reviewed and evaluated from a practical standpoint rends in the development of cornmiter systems, their
Tcontrol and non-control applications, and directions in instrumentation development have been the subject of continuing review (26N). The volume of papers published in this broad field defy exhaustive survey in any single review article. Therefore, this review points out the major trends in the field highlighting equipment and application advances, and pointing out progress in areas such as process dynamics and optimization. The bibliography organized according to areas of progress supplements the review text and gives impressions of rates and directions of progress. Developments in Computer Systems
This past year has been one of major announcements for the computer industry. It has seen development of whole families of computers of a wide range of sizes and possible applications and with program compatibility within the family; that is a program written for any computer of the group will work on any larger member of the group and often on any other member of the group. Such groups of machines have included IBM System 360, the RCA Spectra 70, the GE compatible 400’s and
600’s7 and the CDC 3000 and 6000 series machines. Some of the other manufacturers are expected to announce similar systems of machines in the near future. Second of the major groups of announcements has been the decision of most of the manufacturers to utilize microcircuit techniques, in some cases, an intermediate or modular circuit level, in other cases as far as the state of the art in microcircuit techniques will permit. In any case, the rate of development of microcircuit technology has been so rapid and cost reductions of these components so drastic that it must be the computer circuit technology of the future ( 7 6 4 3 5 4 364). Third of the major announcement areas has been that of the development of a series of small, highly reliable, very fast, and inexpensive computers. Nearly every one of the major computer manufacturers has announced his entry into this field or will do so soon. In addition, many small manufacturers not previously known as computer system suppliers have entered the field. The extremely fast development of these machines was undoubtedly influenced greatly by the very high interest in the area of direct digital control. However, their low price has sparked their application to a vast number of areas, many of them almost undreamed of before the computers themselves became available and showed their extreme utility. The reader will note that we have consistently used the word “announcement” in this discussion. I t is a feature of the computer industry that new developments are announced and sold long before they have been completely built and checked out. Thus some of the VOL. 5 7
NO. 1 2 D E C E M B E R 1 9 6 5
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computers and devices announced over a year ago have still not been built at the time of the publication of this review. This type of procedure, in decided contrast to the automotive industry, for instance, is necessitated by the extremely fast rate of development and obsolescence of this industry’s products. Two other areas of computer technology have also received a major share of the attention over the past year : those of multiple-access computer systems or “computer utilities” ( 7 7A) and of hybrid computers (24.4, 49A, 50.4). The multiple-access computer concept pioneered at M I T ( 7 7A) and by Scientific Development Corporation (SDC) and the RAND Corporation allows a group of up to several hundred users (depending on the computer and the remote terminal equipment) to utilize effectively equipment at the same time and without any apparent loss of capability or interference in the eyes of any particular user. This is done by programming the computer to work on each user’s problem for a small fraction of a second, then to switch to each of the others in turn working on their problems and finally coming back to the first before the user has sensed that he does not have a complete computer for his own use full time. Such a system is, of course, quite inefficient for very large problems. It does, however, work excellently for the usual range of small problems normally encountered in most computer application areas and for program generation, compiling, and debugging. Since so many users are sharing the cost of the computer through relatively inexpensive typewriter-like consoles, the overall cost to each is small particularly in view of the computing power available to him. Thus, these systems promise to be a major factor in the computer applications field in the immediate future. Already each of the major manufacturers is offering such capabilities to its customers, not only on a rental basis for single or multiple terminals, but also for complete systems to be installed throughout a customer’s plants or offices. During the past year hybrid computers, which are combinations of digital and analog computers so designed as to reap the advantages of the best features of each when applied to the same problem, reached a sufficient maturity so that such systems are now procurable from several different manufacturers. Most important, adequate programming packages are now apparently available to make the use of these systems by the average industrial customer practical and worthwhile. These computer systems are especially suited for application to multiloop optimization problems; families of partial differential equations; nonlinear differential equation systems; and for nonlinear function generation and control response studies. Other items worthy of note are the continued development of optical readers for entry of various types of printed or written material directly into computers without intermediate key punching, and the appearance of truly mass memories with fast access times, such as the one million character core memories developed by IBM, the “fire hose” drum memory system of GE, and the 34
I N D U S T R I A L A N D E N G I N E E R I N G CHEMISTRY
development of large, very fast, disk systems by each of the several manufacturers. The reader will be interested in comparing today’s high level of progress in computer systems and their application with the original proposal for a large scale computing mdchine. The IEEE Spectrum has republished (7A), Professor Howard Aiken’s pioneering proposal to IBM which led eventually to the Harvard Mark I, the first practical digital computer. A major area of concern throughout the digital computer field is the supply of personnel to develop and write programs for the ever increasing numbers of machines being built and installed. Our only hope is that the development of automatic programming systems and of standard programs will come along fast enough to relieve this ever-increasing burden. This concern applies to process control application areas as well as those of engineering design, management aids, and scientific problem solving. Noncontrol Applications of Computers
For the process engineer reading ISDUSTRIAL AND ENGINEERING CHEMISTRY, the possibilities of computer application to the engineering design of chemical and petroleum plants are of primary importance. While much has been accomplished in this area in terms of the computer mechanized solution of the design equations for distillation columns, cracking furnaces (27B), heat exchangers (78B), reactors (6B),and other pieces of unit operations apparatus as individual items, very little has yet been accomplished to integrate these into an overall automatic plant design system. In the area of overall heat and material balancing (25B,27B), with economic factors, especially where linear programming techniques can be applied, much has been done, particularly by industry. However, the true man-machine interchange system via cathode ray tube readout which has shown its importance to the areas of electronic circuit design, highway and bridge design, and mechanical design (23B, 28B) has as yet been little exploited by our industry or our universities for chemical plant or refinery applications. Analog computers as well as digital computers are showing their worth for design. This has been mainly through the medium of simulation. Such applications have been published for heat exchangers (4B, 30B), distillation (7B), absorption (8B), and reaction systems (24B, 29B), as well as for control system design and evaluation (72B, 73B). In addition to the design area, computers are continuing to prove their worth for process development applications ( I B , 73B), and for project AUTHOR Theodore J . Wzlliams is Professor of Engineering and Director of the Automatic Control Laboratory, Purdue Lhiversity. H e has authored IBEC’s annual reviews on process control and automation since 7958. H e ackowledges the assistance of ATancy L. Cromer, who was instrumental in the collection and preparation of the exhaustive bibliography which served as the basis fw this article.
evaluation through PERT and similar techniques ( 7 7B, 76B). A new and potentially very important area of application for the small computers mentioned earlier is in the operation of “automatic laboratories” and data collection systems. By using data techniques developed in the process computer control field, computers can now monitor the operation of laboratory instruments and reduce their resulting data to typewritten or otherwise transmitted analyses with more speed and efficiency than any human operator. This also promises to be a very important application area in the immediate future. Computer Applications in Control
Direct digital computer control has continued to be the area of major interest in the computer control field and indeed in all process control. As mentioned above, many manufacturers have announced computers especially designed and built for this application (ZC, 3C, IOC, ZZC, 31C, 39C, 40C, 43C). In fact, a review of the field shows that 25 different models of computers can now be obtained from 21 different vendors. Users have responded with an equal interest and application of these systems. A recent survey was able to pinpoint 20 known applications in industry and admitted that this number was undoubtedly much lower than the actual figure since many new applications have not yet been announced by either manufacturer or user. An amazing aspect of the field has been the proliferation of new concepts and new developments even before the older ones have been adequately proven or disproven by the user’s experiences. For example, one of the early concerns of both user and manufacturer has been that of computer reliability and hence the need for the development of inexpensive but nevertheless very capable manual backup systems. Recently, however, vendor’s proposals have in many cases featured multiple computers and little or no manual backup capability. This has been done long before any field applications have had a chance adequately to determine the expected life of the small computers which are the heart of these systems. While it is still early in the history of direct digital control and, as mentioned above, user experience is still scarce, some reports are beginning to appear (9C, 72C, 57C). This availability promises to increase rapidly in the near future. The field of digital control in general has received major benefit from the Symposium on Application of Digital Computers to Process Control held under the joint auspices of the International Federation of Automatic Control and of the International Federation for Information Processing at Stockholm, Sweden, in September 1964. Papers were presented there on all aspects of computer control. Especially to be noted were those in steelmaking (IC, 42C), direct digital control (57C), power generation ( 7 4 2 , 32C, 45C), chemical and petroleum processing (79C, 24C, 36C), papermaking (30C), and cement making (482). The complete pro-
ceedings will be published jointly in the near future by the Instrument Society of America and Plenum Press, Inc. I t is always interesting to review the latest list of applications of process control computers. One is impressed with the rate of growth and wide base of the field as well as by the variety of areas to which they have been applied. Control Engineering magazine (78C) and T h e Oil and Gas Journal (27C) feature such reports a t annual or even shorter intervals. Analog computers continue to show their great potential for application to process control problems (6C, 13C, 50C, 56C). They are, however, faced with a growing competition from the direct digital control computer because of the specific nature of most of these installations and the resulting high engineering charges involved for their design, construction, and application. Presumably application of digital control to these areas will be much easier since they would in general involve only programming changes to the computer itself rather than a complete engineering and construction task as would the corresponding analog application method. Major future areas of computer control development will be in the manufacturing areas (5C), and of especial importance that of testing and checkout systems (7C). These latter are of major interest for the process industry user to follow since they promise to be important aids in the development of automatic start-up and shut-down systems for chemical plants and petroleum refineries. This should be the next major area of development in the process control field once the direct digital control concept has been proved and is generally accepted. Instrumentation
The major developments in instrumentation during the past year have been the continued demonstration by computer data systems of the inherently low accuracies of conventional plant sensors and their related control systems and the growing interest in the concept of intrinsic safety and its possible standardization for process control systems in this country. Rather than the 0.5-1 .O% accuracy usually attributed to them by the manufacturers, most plant instruments, even under good calibration and maintenance practices, appear to give results whose overall accuracy is in the 1-2% or even higher range. As mentioned above, this has been brought forcefully to our plant personnel’s attention because of the lack of closure in material and energy balances generated by digital data systems. This has resulted in a growing expression of desire for a set of plant instruments which can consistently give results in the 0.1% range. These now appear to be forthcoming. Intrinsic safety, or the use of electronic instrumentation systems whose power outputs can never reach the levels necessary to cause an explosion in a flammable mixture (35E), has been actively promoted by the Instrument Society of America in several recent training sessions, It will be a very important development if its use can be standardized and accepted by the fire inV O L . 57
NO. 1 2
DECEMBER 1 9 6 5
35
ANALOG AND DIGITAL COMPUTERS Subject
INSTRUMENTATION TECHNIQUE (GENERAL) Subject
References
Analog Computers-General Character Recognition Communications via Computers Digiral Computer Design Digital Computers-General Historical Aspects of Computers Hybrid Computers Multiple-Access Computer Systems Optics for Computer Use Peripheral Equipment for Memory Use Pneumatic Computer Elements Programming Languages-General Programming Languages-Specific Simulation Small Size Computers Solid State and Integrated Circuits
(6A, Y A , 22A) (704 ( 7 Y A , 20.4, 378) (411, 158, 77A, 57A, 53A) ( 78A, 28A, 4 5 A , 4711) ( 7 4 ( 2 4 4 , 4 9 8 , 508)
(77.4)
(8.4,3 8 A ) ( 4 7 A , 43.4, 46A) (7’4)
( 3 8 , 72A, 21A, 25$, 37.4, 3YA, 52A) (211, 5A, 748, 23.4, 32A, 40A, 4 2 A , 54A) ( 7 3 A , 2 Q A , 308, 34A,48A) (27A) (76A, 268, 33A, 3 5 A , 3 6 A , 4 4 A )
COMPUTER USES OTHER THAN CONTROL Subject
References
Analog Computers for Design Design Applications Evaluation of Laboratory Data Heat and Material Balances Hybrid Computer Applications Language and Character Recognition Mathematical Methods Process Development Project Evaluation Techniques Simulation Applications Simulation of Control System Responses Simulation Techniques-General
(58,208, 268) ( 6 8 , 188, 278, 238, 288) (38) (258, 278) ( 2 8 , 708, 778) (7S8,228) (748, 758, 328) (7B, 338) ( 1 7 8 , 168) ( 4 8 , 7 8 , 88,2 4 8 , 298, 3 0 B ) ( 7 2 8 , 738) ( Y B , 318)
References
Accuracy and Error Analysis Analysis Instrumentation Flow Measurement
1
Freq.uency-Modulation . Gas Chromatography Graphical Displays Intrinsic Safety Laboratory Instrumentation Laser Techniques Level Measurement Measurement Techniques, General Moisture Measurement Nuclear Techniques Position Measurement Pressure hleasurement Sampling Rates Temperature Measurement Transducers TVeighing
~
(79.5, 28E, 4 3 E ) (7E, 29E, 3 Y E , 53E) (5E,13.5, 74E, 77E, 21.5, 22E, 34E) (20E) (4iE, .50E) (25E)
(35E) (24~) (37E, 38E) (3E, 23E, 26E, 27E, 40E) (le,2.5, 4E, 72E, 42E, &E, 52E) (30E, 3322, 47E, 49E, 57E) (16E, 36E, 3 7 E , 47E, 4 8 E ) (78E) (43E) (75E)
(9E) (GE, 8E) (70.5, 77Ej
PROCESS LOOP COMPONENTS AND INSTRUMENTATION HARDWARE Subject
Referencci
Actuators Chromatographs and Programmers Controllers, Analog and Digital Density Gages Flow Meters Fluid Amplifiers p H Meters and Electrodes Recorders Sampling System!; Bet Point Station!. Strain Gages Thermocouples Valve Sizing and Selection
COMPUTER CONTROL AND RELATED TOPICS Subject
PROCESS DYNAMICS
References
Subject Analog Computers for Conrrol Cement Plants Computer Control-General
(6C, 73C, 50C, 56C) (ZSC, 4SC) ( I l C , 7YC, ZYC, 4 4 c , 4 7 c , 4QC) (ZC, 3C, 4C, 70C: 22C, 37C, 39C, 40C, 4 3 C ) (75C, 23C, 26C, 5 8 C ) (78C, 21C)
I ~
’
Computers for Direct Digital Control
I
Direct Digital Control-General Lists of Computer Installations Manufacturing Applications Nuclear Power Plants Paper hfills Petroleum and Chemical Plants Pipelines Power Plants and Distribution Systems Railroads and Transportation Systems Reports of Applications of Direct Digital Control Simulation of a Direct Digital Control System Steel Mills and Furnaces Testing Systems
(52~) (VC, 3x7, 38C) (25C, 30C, 57C, 55C) (24C, 33C, 36C, 37C) (53C, 54C) (14C, ZOC, 32C,47C, 45C, 46C) (.5C) (YC, 72C, 5 7 C )
(27C) ( 7 C , SC, 76C, 34C, 42C)
1
Subject
References -
Analog-Digital Converters Automatic Testing and Analysis Systems Data Handling-General Data Transmission Digital Differential .4nalyzers Digital Magnetic Recording Electronic Switching Devices 1/0 Systems for Direct Digital Control Specification Telemetry
36
~~
~
Experimental Dynamics of Distillation Columns Experimental Process Dynamics-Genera Fluid Amplifier Dynamics Frequency Response Heat Transfer Dynamics Kinetics and Reactor Analysis Kinetics of Some Specific Systemr Process Dynamics-General Pulse Testing Reactor Dynamics Reactor Stability Theoretical Analysis of Distillation Column Dynamics Theoretical Development of Process D p a m i c s Models
I
‘ j
I
~~
~
~
INDUSTRIAL A N D E N G I N E E R I N G CHEMISTRY
(78G, 27C, 28G) (24G, 27G)
(7G. 22G, 26G) (3G, 73G, 74G, 16G. 23G) (5G, 20G) (IZG, 75G) (IOG, 77G) (ZG, 6G, 7G, 77G)
1
(7YG)
I
(YG, 2YG)
I
(SG)
PROCESS CONTROL T H EO RY-BAS 1C Subject
ANALOG-DIGITAL CONVERSION, PLANT DATA HANDLING, TELEMETRY, AND RELATED TOPICS
~~
References
Compensation for Process Dynamics Controller Mode Settings Frequency Response Lahorarory Experiments h’on-Interacting Control Systems Orthogonal Functions Phase Plane Use Polynomial Factoring Process Control and Process Design Sampled Data Systems Signal Flow Graphs Stability Criteria Texts and Basic Theory Time Response Computation Tzends in Control Z Transform Use
Refwencar
1 1 ’
I’ i
~
1’
(29H) (6H, Y H , 15H, 20H, ,?5H) ( 7 0 H , 7YH, 3 7 H ) (32H) ( 2 4 ~ )
(30H) ( 7 6 H , 27H, 27H, 3 3 N ) (7H) (5H) (2H) ( 3 H , 72H. 7413, 2 3 H ) (SH, 13€I, 77H, 78H, 25H, Z S H , Z S H ) (22H, 34”)
(4fG (7H)
surance companies because of the savings in installation costs which will result since conduits and explosion-proof housings are no longer required for fire safety. An intriguing development has been the application of the laser as an anemometer ( 3 I E ) . Its application as a flowmeter appears possible. I n such use it will be subject to the same sources of error as would sonic flowmeters. The small digital computers, however, promise to be able to compensate for temperature, pressure, and composition effects and thus take advantage of the inherent advantages of these types of measuring systems. Process Dynamics and Process Control
In the field of process dynamics the major interest has continued to be in distillation columns, heat transfer systems, and chemical reactors. Gerster and coworkers have continued their excellent work in overall column dynamics (78G); while Mohr (2IG) studied the effects of various equilibrium relationships, and Welch, Durbin, and Holland (28G) that of valve trays and downcomers on column tray dynamics. Horn and Miller showed how predictive mathematical models could be developed (9G) while Zykov et.al., showed the use of plant data for determining column models (29G). In the area of plant testing, Hougen (IOG) published a monograph through the AIChE on the pulse testing method he and his associates ( 7 IG) have publicized over the past several years. Schiesser (24G) and van der Grinten (27G) present other methods for procuring the same type of information from different types of plant tests and plant records. Concerning heat exchanger behavior, it is worth noting that Profos who published the first authoritative paper on process dynamics has just published another of his continued important papers in this area (22G). Other important papers in this area are those of Adiuteri ( I G ) on boiling stability and Stermole and Larson (26G) on flow forcing in distributed parameter systems. The University of Minnesota group has continued to publish extensively from their very productive, and important project in reactor analysis, dynamics and optimization (ZG, 6G, 7G, 71, 41, 381, 391, 2L). Other papers on these subjects worth noting have been published by Leung and Quon (77G) and McGuire and Lapidus ( I9G). Reaction kinetics, their determination and their effect upon reactor performance, has received some of the attention it deserves with papers by Hunter and Mezaki (I3G), by Kaperman and Kaplan (74G), by Letts and Mickley (76G), and by Reed and Gottfried (23G). Kinetics of some specific systems were presented by Davidson and Thodos (5G), and Miller, Nayce, and Vermuelen (ZOG), among others. The process control field benefited during the year through the appearance of three excellent new textbooks. These were “Process Control” by Peter Harriott (74H), “Process Systems Analysis and Control” by Donald Coughanowr and Lowell Koppel ( I I H ) , and “Techniques for Process Control” by Page S. Buckley ( 8 H ) . These books fill a very definite need which our
universities have had for adequate texts in this field for some time and which could be only partially filled by the available electrical and mechanical oriented texts mainly because of a lack of suitable problems. Another very valuable aid to the university instructor will be the series on the process control laboratory experiments published in the ISA Journal by Stice and Swanson (33H). Advanced control systems for distillation columns are discussed by Carter (34 in his series on process plant controls, by Lupfer and Johnson ( 9 J ) in a continuation of the series from the Phillips Petroleum Company, and by Luyben and Gerster (7OJ) reporting on the developments in feed forward control from the University of Delaware laboratory. Some very interesting discussions of overall control system applications in industries are presented by Frank (6K) for the pharmaceutical industry ; by Finkelstein (47C) for the coal mining industry; by Curtis ( 3 K ) for the papermaking industry; and by Gartner ( 7 K ) for the electrical power industry. Stormont ( I I K ) has given a preview of the petroleum refinery of the future and the expected developments in control systems and computer control. The reader who is not completely familiar with and who desires an excellent review of the meaning, application, and expected development of the advanced areas of adaptive control and optmization will benefit greatly from reading the articles by Pun (321). He does an excellent job of explaining each of the available techniques and putting it in its probable best relationship to the others. The article by Shenners (371) is also recommended for this purpose. The tutorial article by Rikoff (331) gives a good explanation of the recently popular state variable technique for expressing mathematical models of control systems and process dynamics. The adjustment of mode gains or “tuning” of process plant controllers has been a continued problem for the process instrument engineer. I t is appropriate then that the ISA Journal has seen fit to reprint the famous articles by Ziegler and Nichols on this subject (36H). That this is a continuing problem is shown by the new articles which continue to appear on this subject such as those of Buckley ( 7 H ) , Coon (7OH), Jacques (76H), and Liptak (27H). For some excellent discussion of control problems and their solutions in other fields, the reader is invited to study the articles on the Telstar antenna system by Lozier and associates (701, 791) and on aircraft flight simulation by Marienfeld (231). Optimization
The various optimization techniques continue to be studied extensively by many university and industry groups because of their obvious long-range importance to industry. Many of the advances spurred by this industrial trend are covered in the Mathematics review in this issue of I&EC. As a result, a large number of methods applied to a wide variety of examples have been presented. Most of these examples are still quite VOL. 5 7
NO. 1 2
DECEMBER 1 9 6 5
37
CONTROL SYSTEM THEORY-ADVANCED
CONCEPTS APPLICABLE T O PROCESS CONTROL Subject
~
~~
References
~
Adaptive Control of Batch Reactors Adaptive Conrrol System Theory Advanced Texts Aircraft and Space Vehicle Control Chebychev Approximation Methods Distributed Parameter Systems Mathematical Theory of Automata Minimum-Variance Estimation Multivariable Control Systcms h-ear-Optimal Control Nonlinear Systems Optimal Control System Theory Overdetermined Systems Control Parameter Variation Pulse Time Delay Reactor Control by Pontrl-agin's Methods Sampled-Data Systems State Variable Techniques Telstar Antenna Control Variational Calculus Applications
~
~
~
~
(JI) (21, 111, 291, 321, 341, 371. 441) (181, 211, 221, 251, 411) ( S I , 121, 201, 231) (31) (1 0 (311) (401)
(4'W (16.M)
(2l'M)
(301) ( 151)
(381,391) (51, 141, 271, 421) (331) (101, 791) (351)
References
INSTRUMENTATION AND CONTROL APPLICATIONS (SYSTEMS) Subjeci
References
Pharmaceutical Plant Control Pilot Plant Automation Pipeline Control Ultrasonics for Industrial Control
(6K) (2K,
8x1
(70x1 (7K)
OPTIMIZATION THEORY AND TECHNIQUES (NONCONTROL)
38
(20;M)
(241, 361) (61, 71, SI, 131, 171, 281) (431)
Automatic Analysis Batch Distillation Programming Distillation Column Control Heat Transfer Measurements Process Instrumentation and Conrrol-General Reactor Control Sampling Systems Strain Gage Applications Temperature Control Water Treatment Control
Computing Methods Dynamic Programming Gradient Techniques Linear Programming h-onlinear Programming
( 5 M , 8.M)
(261) (161)
INSTRUMENTATION AND CONTROL APPL I CAT10 NS (INDIVIDUAL) Subject
Calibration Techniques Contract Maintenance Economics of Automarion Instrument Air Supplies Instrument Mainrenance Outlines
(3L) (7L) (SL) (4L, 15L) (6L)
INDUSTRIAL A N D E N G I N E E R I N G CHEMISTRY
limited because of the computational problems in solving the equations of the optimized system but some dramatic results are still shown by these examples. Merriam (251)and Tou (471, 421) have published texts in the area of control system optimization and Balakrishnan and Neustadt (3L) in the area of computing methods for solving optimization equation systems. The use of the variational calculus is treated in examples by Ruiz (351). Dynamic programming is used in a paper by Ahn, Chen, Fan, and Wan (7L). Pontryagin's maximum principle is used by Siebenthal and Aris (381,391), Fan and Wang (7L), and by Lee (9L). Other techniques used are linear programming by Beightler and Wilde (4L) and Van Cauwenberghe (75L); nonlinear programming by DiBella and Stevens (6L) and gradient techniques by Lee (8L). The very large computing loads required for solving real optimization problems to the exactness theoretically possible makes the possibility of near-optimum methods very intriguing. One form these could take is given by the paper on small perturbations by Kushner (761). Personnel, Education, and General Impact
As we remarked earlier, the process control application area, particularly computer control is beginning to face a serious problem of a shortage of people qualified to carry out the specification, installation, programming, and operation of these systems. Thus both our universities and industry will be pressed to develop new- and highly concentrated yet effective training programs in the very near future to satisfy this need. We will have to do for the computer application engineer and the computer maintenance man what has recently been done for the analog instrument maintenance man and engineer in the chemical and petroleum industry. The articles by Hultgren ( I O M ) , Warren and Hultgren ( Z I M ) , and Schiff ( 7 9 M ) describe some of these latter methods and the results obtained. Another very important training innovation is the use of analog simulators to give operators training on a new plant before start-up. It allows simulation of various faults without endangering the plant or the personnel and thus assures a smoother and more rapid start-up and better operation afterward. Lieber ( 7 2 M ) , Lieber and Herndon (13M), Weltge and Clement ( Z Z M ) , and
_ .
Automatic Cvntrol Education Bibliographies Computers-General Computer Learning Systems Critical Path Methods Developments Overseas Engineering Mechanics Information Retrieval Mathematical Modeling of Marketing Monte Carlo Techniques Programmed Learning and Teaching Machines Programming of Computers Progress and Future Developments Reliability Systems Engineering Theory and Practice
_-
(24N) (26N) (7IN) (72N) (77N) (3N, 5 N , 2 3 N ) (8N, 9N) (76N) (7 3 N ) (2ZW ( I N , 7 N , 25N) (18N) ( Z N , 4 N , 6 N , 14N, 1 5 N ) ( I Q N ,2 0 N ) W N ) (ION)
Whitesell and Bowels (23M) have all written articles on this subject. The January 1965 issue of Control Engineering, the March 1965 issue of Control, and the June 3,1965, issue of Chemical Engineering all contain excellent reviews of the state of the art in instrumentation and control and predictions of the future progress of this field. They are recommended to the reader. Control developments in other countries are covered by several of the articles in the Control Engineering issue just mentioned (3N, 5N, 23A7). In discussing the future of the field, the relation of present-day developments in control theory versus the present status of control applications particularly in the context of a gap between theory and practice is worth of discussion. The round table discussion chaired by Hessenberg (70N) has much interesting comment on this point. BIBLIOGRAPHY Analog a n d Digital Computers (1A) Aiken H “Proposed Automatic Calculating Machine,” I E E E Spectrum 1, No. 8 , 62-69’iAugust 1964). (2A) Backus, J. W., Heising, W. P., “Fortran,” I E E E Trans. Electron. Computers EC-13, NO.4, 382-385 (August 1964). (3A) Braffort P. Hirschberg, D., “Computer Programming and Formal Systems,” 161 pp., Ndrtd-Holland Pub. Co., Amsterdam, Holland, 1963. (4A) Braun, E. L “Di ital Computer Design-Logic, Circuitry and Synthesis,” Academic Press,”New f‘ork, 1964. (5A) Caxleton, J. T . , Lego, P: E;,, Suarez R M. “A FORTRAN Extension to Facilitate Proposal Preparatlon, M E E k r a i s . Electron. Computers EC-13, No. 4, 456-462 (August 1964). (6A) Celinski 0 Rimawi, I. H., “Classification of Analog Multipliers,” Znstr. Control Systek 3?, No. 6, 149-156 (June 1964). (7A) Chapin, D. W., “How t o ComputePneunratically,” Chem. Ens., 72, No. 5, 93-97 (March 1, 1965). (8A) Cutrona L. J. “Optical Computing Techniques,” I E E E Spectrum 1, No. 10, 101-108 (Ottober’1964). (9A) Fairchild, B. T., Krovetz, L. J., “10 Circuits for Differentiation on Analog Computers,” Control Eng. 12, No. 2, 65-68 (February 1965). (10A) Falk, H. “Optical Character-Recognition Systems,” Electro- Technol. 74, No, 1, 42-52 ;July 1964). (11A) Fano, R . M., “The MAC System: T h e Computer Utility Approach,” I E E E Spectrum 2, No. 1, 56-64 (January 1965). (12A) Floyd, R. W “The Syntax of Programming Languages-A Survey,” I E E E Trans. Electron. Co’hputers EC-13, No, 4, 346-353 (August 1964). (1 3A) Freeman D. E “Programming Languages Ease Digital Simulation,” Control Eng. 11, No. li’, 103-108 (November 1964). (14A) Gaskill, R. A “A Versatile Problem-Oriented Language for Engineers,” I E E E Tinns. Electroa. Computers EC-13, No. 4, 415-421 (August 1964). (15A) Gutenmakher, L. I , , “Electronic Information-Logic Machines,” 170 pp., Interscience, New York, 1963. (16A) Haggerty, ; : E. Hogan C L No ce R . N Maier L C. Brown J. E Knowles, C. H., Intkgrated ~ir,,i;~,.’I~EESpectr;m i,No.)2, k2-89 (June)1964$: (17A) Hoernes G. E. Heilweil M . F. “Introduction toBoolean Algebra and Logic Design,” 306‘pp., McGraw-Hill, N;w York, 1964. (1 EA) Hoffmann, Walter (Ed.), “Digital Information Processors,” Interscience, 740 pp., New York, 1962. (19A) Holloway, C., Jr., Balint, F. J., “Computer-To-Computer Communications,” Oil Gas J . 62, No. 48, 70-72 (November 30, 1964).
(20A) Holmes, J. F., “Specifying a Message Switching Computer,” Control Eng. 12, No. 2, 89-92 (February 1965). (2iA) International Computation Centre, “Symbolic Languages in D a t a Processing,” 849 pp., Gordon and Breach, New York, 1963. (22A) Johnson C. L. “Analog Computer Techni ues ” 298 pp. f 7 index pp., xii pp. 10’appenhix pp., McGraw-Hill, New%ork, 1963. (23A) Knuth D E McNeley J. L “SOL-A Symbolic Lan uage for GeneralPurpose Syitems &nulation,:’ Z E E h Trans. Electron. Computers %C-13, No. 4, 401414 (August 1964). (24A) Korn G A Korn T. M “Electronic Analog and Hybrid Computers,” McGraw-Hili, 5& pp., k e w Yo‘ik, 1964. (25A) Landweber P. S. “Decision Problems on Phrase-Structure Grammars,” I E E E Trans. E l & m domputers EC-13, No. 4, 354-362 (August 1964). (26A) Lessor, A. E., Maissel, L. I., Thun, R . E., “Thin-film Circuit TechnologyPart I,” I E E E Spectrum 1, No, 4, 72-80 (April 1964). (27A) Linebarger, Paul, “The Desk Computer,” Instr. Control Systems 37, No. 10, 145-155 (October 1964). (28A) Maley, G. A,, Skiko, E. J., “Modern Digital Computers,” 216 pp., PrenticeHall, Englewood Cliffs, N. J., 1964. (29A) Matthews, T., “Analog Simulators,” Chem. Eng. 72, No, 1, 79-84 (January 4, 1965). (30A) Matthews, T “ f i o w t o Analyze the Circuits and Mathematics of Analog SimulatotB,” Ibid.:’No. 3, 79-84 (February 1, 1965). (31A) McKenzie, A. A,, Catz, P., Mikton, R., Erikson, A,, Landon, N., Skole, R., “New Era in Telephony: Electronic Switching,” Electronics 37, No. 27, 71-86 (October 19, 1964). (32A) Mullery, A. P. “A Procedure-Oriented Machine Language,” I E E E Trans. Electron. Cdhpulers EC-13, No, 4, 449-455 (August 1964). (33A) Narud, J. A., “Integrated Circuits,” Znd. Res., 1964,No. 12, pp. 30-38. (34A) Page, C., “Scaling for Analog Simulation,” Instr. Control Systems 37, No. 9, 168-1 72 (September 1964). (35A) Phillips, A. B., “Monolithic Integrated Circuits,” I E E E Spectrum 1, No. 6, 83-101 (June 1964). (36A) Philips, M. H., Jr., et al., “Microelectronics-Present and Future,” ElectroTecknol. 74, No. 2, 107-116 (August 1964). (37A) Proctor, R. M. “A Lo ic Design Translator Experiment Demonstkating Relationships of Laniuage to &stems and Logic Design,” I E E E Trans. Electron. Computers EC-13, No. 4, 422-430 (August 1964). (38A) Rqjmann, 0. A,, Kosonocky, W. F., “Progress in Optical Computer Research, I E E E Spectrum 2, No. 3, 181-195 (March 1965). (39A) Rome, B., Rome, S., “Programming the Bureaucratic Computer,” I E E E Spectrum 1, No. 12, 72-92 (December 1964). (40A) Sammet, J. E., Bond, E. R “Introduction t o FORMAC,” Z E E E Trans. Electron. Computers EC-13, No. 4, 3b6-394 (August 1964). (41A) Schaar, M. G., Biodo, I. D., “Disc File Memories,” Instr. Control Systems 37, No. 7, 85-88 (July 1964). (42A) Schlaeppi, H. P., “A Formal Language for Describing Machine Logic, Timing, and Sequencing (LOTIS),” I E E E Trans, Electron. Computers EC-13, No. 4, 439-448 (August 1964). (43A) Schmidt, E., “Magnetic T a p e s t a t e of the Art,” Instr. Control Systems 37, No. 6, 121-122 (June 1964). (44A) Seidman, A. H., ‘‘Solid-state Principles,” Electro-Tecknol. 74, No. 6, 57-58 (December 1964). (45A) Solodovnikov, V. V. (Ed.), “Automatic Control and Computer Engineering,” Vol. 2, Macmillan, New York, 1964. (46A) Staff of Cresop, McCormick and Paget, “Computer Equipment Com arison Series No. 17-Magnetic Tape and Random Access Devices for 16 More hfedium and Large Computers,’’ Control Eng. 11, No. 5, 115-120 (May 1964). (47A) Staff of Cresop McCormick and Pa et “Computer Equipment Comparison Series, No. 18, Pfogessors and Combine3 F k t i o n Times for 16 More Medium t o Large Computers,” Ibid., No. 7, 77-83 (July 1964). (48A) Tocher, K. D., “The Art of Stimulation,” 184 pp,, Van Nostrand, Princeton, N. J., 1964. (50A) Truitt, T. D., “Hybrid Computation-What Is It?-Who Needs It?,” I E E E Spectrum 1, No. 6, 132-146 (June 1964). (49A) Truitt, T. D., “Hybrid Computers,” Ind. Res., 1964, No. 12, pp. 40-48. (51A) Weber, S . , “Modern Digital Circuits,” McGraw-Hill, New York, 1964. (52A) Wells, M. B., “Aspects of Language Design for Combinatorial Computing,” I E E E Trans. Electron. Computers EC-13, No. 4, 431-438 (August 1964). (53A) Will, P. M., “Design of Digital Computers for Real-time Working,” Control 8, No. 77, 557-560 (November 1964); No. 78, 619-622 (December 1964). (54A) Woodger, M., “Algol,” I E E E Trans. Electron. Computers EC-13, No. 4, 377-381 (August 1964).
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Computer Uses Other Than Control (1B) Anderson C. R. Lamb D. E. “Naphthalene via Hydrodealkylation-Cornarison of Piiot and’cqmmkrcial h a n t Data with an Analog Computer Model,” ENG.CHEM.PROCESS DESIGNDEVELOP. 3, No. 2, 177-182 (April 1964). (2B) Andrews, J. M., “Hybrid Computer Gives Advantages,” Hydrocarbon Process. Petrol. Rejfiner 43, No. 12, 87-90 (December 1964). (3B) ,Aslund, N. R. D., Cronhjort, B. T., “Evaluation of Spectrochemical Data Using Digital Techniques,” I B M J . Res. Deuelop. 8, No. 2, 160-169 (April 1964). (4B) Barabaschi, ,S., Conti, M., Gentilini, L., Mathis, A,, “Heat Exchange Simulator,” Automalzca 2, No. 1, 1-13 (June 1964). (5B) Coughanowr, D. R., Stensholt, E. O., “Analog Computer Method for DesignIng a Cooler-Condenser with Fog Formation,” IND.ENO.CHEM.PROCESS DESIGN DEVELOP. 3, No. 4, 369-373 (October 1964). (6B) Dassau, W. J., Wolfang, G. H., “Reactor Design Considers Stability and Control,” Hydrocorhon Process. Petrol. Refiner 43, No. 12, 76-82 (December 1964). (7B) Deland, E. C. Wolf M. B. “New Method for Simulation of Multicom onent Distillation,” IN;. EN;. CHE$. PROCESS DESIGNDEVELOP.3, No. 2, 1gO-106 (April 1964). (8B) Egger, C. T., Osburn, J. O., “Simulating an Adsorption System,” Instr. Control Systems 38, No. 2, 156-158 (February 1965). (9B) Forrest, J., “Simulating High-Order Algebraic Equations with Linear Analog Computer Elements,” Ibid., No. 3, 162-164 (March 1965). (10B) Frank, A La idus L. “Hybrid Computations Applied to Countercurrent Processes,” Cikm. l%g. Prog;. 60, No. 4, 61-66 (April 1964). (11B) Frantz R A. Jr. Nothern L B. “Project Control Using PERT,” Electrc2,’87-)91 (Auguit 1’964). Techhnol. 74,”;. (12B) Gaines, W. M., Goshorn, L. A,, Livingston, R. G., “Analog Computers for the Dynamic Evaluation of On-Line Di ital Control Computer Programs,” Automatica 2, No. 3, 179-193 (January 19657.
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DECEMBER 1 9 6 5
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(13B) Gregorv S. 0. “Using Analog Computers in Automatic Controller Testing,” Insti. Controi k’stemj 38, No. 2, 151-154 (February 1965). (14B) Hausner A. “The Solution of Lagrange’s Equations bv Analog Computation,” IEEE’7ra;s. Electron. Computers EC-14, No. 1 , 53-61 (gebruary 1965). (15B) Ingels, R. M., “How t o Solve Non-Compatible Simultaneous Equations,” Chem. Eng. 71, No. 22, 133-136 (October 26, 1964). (16B) Kadet, J., Frank, B. H., “PERT for :he Engineer,” IEEESpeciram 1, No. 11, 131-137 (November 1964). (17B) Karplus, W. J., “A Hybrid Computer Technique for Treating Xonlinear Partial Differential Equarions,” I E E E Trans. E!ectron. Computers EC-13, No. 5, 597-605 (October 1964). (18B) Katz D. L. Briggs D. E., “A Bright Future for Computers in Heat Transfer,’’ Che;. Eng. )Progr. $1, No. 1, 91-96 (January 1965). (19B) Kjrsch R . A. “Computer Interpretation of English Text and Picture ParEC-13, No, 4, 363-376 (,4ugust 1964). terns, I E E E Trar15. Eleciron. CGIII~II~~~J (20B) Levine L. “Methods for Solbing Engineering Problems Using Analog Computcre,” M’cG:aw-Hill, New York, 1964. (21B) Lichtenstein, I., “Designing Cracking Furnaces by Computer,” Chern. Eng. Progr. 60, h-0. 12, 64-68 (December 1964). (22B) Lindgren, N. “Machine Recognition of Human Language-Part I , ” I E E E Spectrum 2, No. 3,’114-136 (March 1965). (23B) Mann, R . W’., “The CAD Project.” “dech. Eng. 87, No. 5, 41-43 (May 1965). (24B) Matthews, T., “Simulating Continuous Reaction Processes,” Chzm. Eng. 71, No, 16, 93-96 (August 3, 1964). (25B) Naphthali L. M. “Process Heat and Material Balances,” Ciiern. Eng. Progr. 60, KO.9, 70-+4 (Sep;ember 1964). (26B) Parker, W. A,, Prados, J. W , “.4nalog Computer Design of an Ethylene Glycol System,” Ibzd., KO. 6,74-78 (June 1964). (27B) Ravicz, A. E., Norman, R. L., “Heat and Mass Balancing on a Digital Computer,” Chem. Eng. Progr. 6 0 , No. 5, 71-76 (May 1964). (28B) Smith C. F. “The Computer in Design Engineering-Today and the Future,” M e c h . Eni. 8 6 , No. 4, 29-35 (April 1964). (29B) Staff of Electronic Associates, Inc., “Simulation of a Stirred-Tank Reactor,” Insir. Control Sjsiems 37, No. 6, 146-147 (June 1964). (30B) Staff of Electronic Associates Inc., “Simulation of Unsteady Stare Heat Conduction,” Ibid., No. 8, 124-12; (August 1964). (31B) Staff of GPS Instrument Co., Inc., “Simulation of Transport Delay,” I h d . , No. 4, 145 (April 1964). (32B) Toor, H. L., “Solution of the Linearized Equations of hlulticomponent Mass Tranrfer,” B.I.Ch.E. J. 10, KO,4. 448-455, 460--465 (Jul)? 1964). (33B) \Volfe, R . K., “Role of Com uters in Process Development,” Chem. En
