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This paper is intended to give some background survey of the “industrial management systems” research in the recent years, and also to give some comments on the six papers in Session 26. Since the industrial management systems is one of the typical large-scale systems with hierarchical structure, the three basic types of hierarchies in industrial management systems, which is systematically proposed by Mesarovic, et al., are presented. Each paper is looked at again from the basic types of hierarchies point of view. Finally, the promising area of future research in industrial management systems is anticipated.

Digital simulation and plant tests have demonstrated the feasibility and the economic advantages of coordinated control of paper machines. The design of coordinated control is discussed, with examples and plant test results of paper machine coordination. On-line simulation models are proposed as an aid to coordination during certain state change, and for use in on-line estimation. The digital computer implementation of the new control schemes is described.

Optimum operative planning task of paper and board production ensuring the most rational loading of paper and board machines and minimum losses at cutting product into reels is formulated as mathematical programming task.

As converting operations increase in speed, the need for greater uniformity in reel performance increases, leading to stricter and more objective specifications of reel properties. This paper reviews efforts to define and control them. Reel properties depend on paper properties, winding tension, reel size, and core properties. The cross directional variations of paper properties and tension cause the main problems in producing satisfactory reels. It has been shown by experiment and by theory that the sheet tension within a reel is lower than its wound-on value; it is usually necessary to increase the wound-on tension steadily to maintain a tight reel. Complications to the calculation of the stress distribution arise from several features: the non-Hookean compressive characteristics of paper, its viscoelastic nature, the spiral form of a reel, friction between layers, and the increase in wound-on tension caused by a drum winder. Assessment of reel quality is based on various tests: visible defects, moisture content, average density, hardness (level and variability), diameter variability, and roundness. The uniformity within one reel is particularly troublesome and many studies have been made attempting to relate reel hardness and diameter variations with, on the one hand variations in web characteristics and, on the other, reel performance.

This paper tells about a computer application in the control and supervision of paper manufacture. The operating system and the control program modules as well as the opportunities of the process operator to interact with the execution of the programs are described in addition to the computer equipment. Control objects are the basis weight, humidity, machine speed and headbox level and pressure. Their essential features are described together with a description of the supervision, which consists of quality and production reports.

This paper describes the computer control system used in the paper mill of Oy Nokia Ab in Nokia, Finland. The computer controlled Yankee Paper Machine produces paper with basis weight from 17 to 72 grams/m2.

This paper constitutes a review of the research work completed at the Computing Center of the USSR Academy of Sciences dealing with the theory of optimal orbit transfers for space vehicles powered by lowthrust rocket engines.

A mathematical model of the drying part, as a controlled member for paper sheet moisture control is being constructed. In constructing it the distribution of temperature along the thickness of the cylinder as well as the distribution of the moisture along the length of the drying part is taken into account.

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.

A brief study has been carried out into the possible applications of real-time infra-red thermal imaging devices in the paper and board industry. Because of lack of experience the interpretation of the displays produced by the devices can be difficult. It appears that under some circumstances the instruments can be used to study non-uniformity problems and though the presence of these can be demonstrated, the data available as yet does not allow detailed diagnosis by employing IR thermal images.

Paper stock flowing at constant velocity through a pipe has a consistency which is proportional to the mass of solids flowing through the system. If the flow is turbulent the local concentration of suspended solids varies in a random manner; these concentration variations are proportional to the mass of suspended solids which can be measured by an electrical transducer. Only the dynamic a.c. component of conductivity is measured and the d.c. component is ignored; in th is way the variation of concentration due to the solids can be accurately measured and any drift in conductivity, due for example to polarisation or to changes in the mean conductivity of the liquid phase, is of no consequence.

1Aim function formulation is given and criterion of optimum stock inlet process control is chosen.2Mathematical stock inlet process model is represented with nonlinear differential equation system with variable coefficients. It concerns the whole stock inlet system and also the stock feeding system, pipelines, stock flowmeter, inlet chamber and so on.3After model linearization and grounding connected with it idealization computerized calculation methods of stock inlet system design are worked out. It allows to increase dynamical stock flow stability during inlet without control systems.4The further increase of dynamical stock flow stability is ensured with feedback control. During computerized investigation transition processes in control system variants the peculiarities of different control systems are found.

The paper describes a control system particularly suitable for processes with long transit time lags, but which is equally suitable for other applications.

The paper describes the physical nature of the origin and maintenance of vibrations resulting from the parametric resonance phenomenon in the “rectifier frequency converter asynchronous motor” system. The paper describes the influence of individual parameters and operational regimes of the system on the origin of these vibrations. It substantiates the application of the method of harmonic linearization for the analysis of parameters of set vibrations. The paper also examines ways and means of controlling the above-wentioned vibrations.

For the choppers with indirect switching is characteristic that after the saturation of the main (operating) thyristor the load current flows for a certain period through the switching (blocking) circuit and only then is switched to the free-wheeiing diode. Hence the load current curve is composed out of three sections. The paper deals with an analytical method for the construction of the current curve for the case when it is possible to neglect the variation of the load current during its flow through the switching circuit. In case this variation cannot be neglected, the solving of the problem can be performed using a computer. The paper offers for that case a universal programme for determining the necessary values for the construction of the curve.

The paper is concerned with the calculation of ac impedance of dc side commutated three-phase bridge inverters. It is shown in the paper that the ac impedance of a PWM three-phase inverter is a complex function of the inverter parameters, the load current, the power factor, the relative pulsewidth and the number of pulses per sixty degrees. A method of calculation based on the ac equivalent circuits of the inverter and computed diagrams are presented to determine the resulting output voltage of dc side commutated three-phase inverters. Finally a control method is outlined for unsymmetrically loaded three-phase inverters.

In this paper, it is shown that the design of a linear control system with following properties: (1) having no steady state error can be guaranteed for all inputs (applied to the control system) and disturbances (applied to the controlled object) described by p-th order polynomials, (2) any set of arbitrarily designated eigenvalues can be always realized, (3) the property (1) of the steady state error can be held unchanged in spite of the change or the ambiguity of system parameters in controlled objects, can be established by the use in combination of state and output (controlled variable) feed-back. Throughout this paper, it is assumed that controlled objects are all controllable observable time-invariant linear systems with m inputs, m outputs and n state variables, and always satisfy a certain condition concerning a steady state solution of the systems. The structure and design formula of the control system for each of the following four cases are given: (1) continuous type of controlled objects (a) with directly measurable states only or (b) with directly unmeasurable states and (2) discrete type of controlled objects (c) with directly measurable states only or (d) with directly unmeasurable states. The practical design procedure and some discussion are also given.

The purpose of this paper is to unify recent advances /1-8/ in the area of computer generation of sensitivity and pseudosensitivity functions and to point out new results which may be obtained from these known achievements. Particular attention is paid to an extention of the existing results to the generation of pseudosensitivity functions for linear multivariable systems whose mathematical models are given in the state space. The methods of generating pseudo sensitivity functions discussed in the paper, facilitate an easy extention of the methods for identification, parameter optimization and synthesis of adaptive systems, so far extensively used in the cases of single-input, single-output systems /8-15/, to linear multivariable systems.

Model Reference Adaptive Systems have been used more and more widely in the last few years to solve various control, parameter identification and state estimation problems. This survey paper tries to present in a systematic way the “state of the art” based on the literature published since 1964 (221 references). Attention is paid to the basic properties and the classification of various types of model reference adaptive systems. The most prominent design methods are reviewed ; unresolved questions and future areas of investigation are also discussed. A survey of the applications already accomplished and those that appear feasible in the near future conclude the paper.

This paper is concerned with a digital computer simulation of the effects of series ventricular assist pumping (intra-aortic balloon pumping) on left ventricular mechanics and arterial hemodynamics. The human ventricle is, in general, characterized by a ventricular elastance function (E) that is a function of end-diastolic volume (V) and time, and the arterial load presented the ventricle is represented by a modified Windkessel model. A model for the intra-aortic balloon pump is also incorporated in arterial load model. The paper demonstrates (1) the characterization of the ventricular mechanics of the normal and failing (coronary artery disease, hypertrophied) heart in terms of elastance functions and (2) the utility of such an overall model in assessing the effects of ventricular assist device pumping on ventricular mechanics and arterial hemodynamics

This paper presents a critical summary of present knowledge of human thermoregulation and indicates areas where definitive information is lacking. There are recent comprehensive review articles (1, 2, 3), so we have chosen to cite only representative papers which illustrate the various approaches which have been used in an attempt to elucidate the human thermoregulatory system.

An earlier paper (1) described the use of high power thyristors in Booster Power Supplies for Glass Melting. Since that time, the availability of even larger thyristors has allowed the economical design of larger Power Supply Systems. This paper describes the design features of a 4.3 Megawatt, Thyristor Controlled, Power Regulated, Glass Melting Power System. The System is installed on a 115 ton mixed melter furnace with bottom electrodes used in the production of Opal Borosilicate Glass. It includes High Voltage Switchgear, Dual Secondary Power Transformers, and Water Cooled Power Cables along with the Thyristor (SCR) equipment. Some information is also presented on electrode peripheral equipment; startup procedures and a method of computing approximate circuit resistance for use in determining controller and transformer voltage and current ratings.

This paper deals with the latest developments and technology of pneumatically handling materials. It deals with the conveying from railroad unloading site to bulk storage, blending the proportioned ingredients, and conveying mixed batch to furnace storage. The paper highlights the latest developments in pneumatic batch blending and portable vacuum conveying units.

This paper deals with the theory of asynchronous motors running at variable frequency. Motor characteristics are found by the help of a computer programme where higher harmonics are neglected, but the influence of saturation is considered. It is shown that it is impossible to get optimum performance if the voltage is a function of the frequency only. A regulator which controls the voltage as a function of both frequency and load to keep constant flux gives torque and current characteristics equal to those of a dc-machine. This paper presents two alternatives for such a regulator. Braking methods are discussed and a regulator principle for a four-quadrant drive without current sensing is shown.

The development of rectifier frequency converters for controlling the velocity of synchronous motors which serve as drives for water pumps is becoming a pressing problem. This task depends to a considerable extent on the correct solution of the problems of starting and damping such systems. On the basis of analysis of starttoperational and damping regimes of the pumping units the paper substantiates the asynchronous start of the motor under low frequencies of the feed voltagetoutlines the zone of starting feed voltage, illustrates the influence of inverter types on the starting characteristic and steady operation of the motor under quasi-stationary start conditions. The paper also examines the influence of the design and parameters of the rotor on the range and rate of capacitor damping.

The main aim of this paper is to show that well known definition of integral square error /ISE/ may be a criterion of comparative analysis of modulation procesees. The effect of analysis of ISE property is that the comparison of pulse signal with model signal by their integrals gives an estimation of shape of the signal which is aiequate to current on the output of inverters. Simultaneously, this ISE is the measure which is corresponding to additional losses in an inverter load caused by deformation of current. As an example of the application of this criterion the results of numerical calculations of ISE versus amplitude of the first harmonic for choosed forms of modulation are given in the paper. The possibility of making synthesis of pulse modulation by minimizing the ISE is also pointed.

The paper presents the results of the investigations of systems approach to air pollution control and urban planning. The problem of environmental pollution and the associated ecological effects are briefly described. The concepts of systems approach and their applications to the current study are explained. The problems of rural and urban planning resulting from rapid industrialisation are discussed. The necessity for considering the environmental impact on the selection of industrial sites, design of processes and the manufacturing methods in the planning stages of industrialisation is explained. Environmental pollution problems from some of the basic industries, viz. Paper and Pulp, Foundries, Iron and Steel, Cement, are discussed. Some of the problems which a developing country should consider, while planning to import technology from industrially advanced countries, are explained.

The paper discusses an on-line computing scheme designed to assist in the predictive control of a large interconnected electrical power system (C.E.G.B., U.K.). The paper claims that man will not merely be a monitor in such a control scheme but will occupy a key rôle in the control loop. It is suggested that this rôle can only be fulfilled if the computer can answer questions about the actual and predicted system state accurately, quickly and clearly.

This paper points to the relative lack of involvement of plant management in the decisions and activities associated with computer process control installations. Evidence is presented which suggests that plant management consistently rate the results achieved by computer control as less than those claimed by systems personnel. The paper concludes by suggesting that there is a need for line management to develop a positive policy for the guidance of computer control within an organisation.

The paper illustrates how a high level process language could enable a project engineer of the future to program the control system of a chemical plant. The process chosen is the manufacture of styrene from ethylene and benzene via the intermediate ethyl benzene. The language employed is Protran, the Fortran based language developed at Nottingham. Programs considered include those for steady control, alarm scanning, automatic start up and shut down, logging, chart and console display, optimisation, provision of management information and linking to other computers. The relation between the computer on the one hand and the process operator, the plant manager and the works management on the other is discussed. The paper shows how the overall program may be split up into sections some dealing with short term tasks such as three term control and alarm scanning others with longer term aspects such as optimisation and scheduling. This splitting also aids the organising of programming manpower. It is concluded that the task of providing a comprehensive control program will be of the same order of magnitude as the chemical or mechanical engineering design tasks.

This paper describes the re-entry control algorithm which provides the prescribed landing point of tae space vehicle entering the Earth's atmosphere at parabolic velocity. The two-dip re-entry scheme is considered and the three dimensional vehicle motion over the both dip portions is investigated. The digital computer algorithm simulation shows that rather high accuracy of the landing coordinates may be obtained even in case of a long distance between the first dip and landing points and in spite of the large-scale uncertaintes in the atmospheric density distribution. The paper develops further the results of /I-6/.

This paper states the basic relations for the active magnetic orientation of the spin axis of spinning satellites. A magnetic coil around the spin axis is used for the generation of the control torques. The coil current is controlled by a simple logic control circuit, the input of which are the measuring signals of a magnetometer and a sun sensor. The spin axis direction can be controlled only at certain switching points. The present paper shows the example of a special satellite mission providing the use of air coils as the most unfavorable case. In this case the electrical energy consumption is less than 0.08 Wh per orbit.

The paper deals with the question of the use of self-learning processes in adaptive systems with least initial information. The mathematical expression, based on the phenomenon of entropy by which the dynamics of the learning and self-learning processes are experimentally determined, is given in the paper. Also introduced is the phenomenon of rate of learning which can give the value of the processes. Some concrete examples of the learning of automata and some living beings are discussed. In the paper are given some experimental data of the results of the self-learning system making the automatic synthesis of the corrective device. According to the experimental data the processes of searching can be significantly lessened by using the methods of learning of the adaptive system. The proposed mathematical expression can be used for the description of different learning processes and makes it possible to achieve some analogies between them. Experiments connected with the self-learning of the adaptive system were carried out on the special electronic machine of the Institute of Electronics, Automatics and Telemechanics of the Academy of Sciences of Georgia.

The paper is devoted to the problem of teaching automatic systems pattern recognition. At the basis of the experiments that were conducted with regard to teaching, lies a profound and original hypothesis relating to the teaching process—a so-called ‘compactness hypothesis’. This hypothesis is interesting in that it opens a path to the mathematical description of the essence involved in the teaching process, which description is not attached to any concrete technical realization of the learning system nor to any concrete pattern type. At the same time, it prompted the experiments described in the present paper, and also made it possible to comprehend already-known studies on teaching.

In Pontryagin's maximum principle and in ‘bang-bang’ control, the manipulated variable is assumed to have no inertia, so that its position changes instantaneously from one value to another. In practice this never happens, for instance in aircraft controls the elevators and ailerons are limited in speed and displacement. The problem is a special case of the more general problem of optimal control in bounded phase space. In this paper a method is given whereby the problem is treated by a limiting process. In place of the rigid bound, a cost function with a multiplied K is introduced for regions beyond the boundaries in phase space. It is shown that in the limit of K approaching infinity, both the added cost and the maximum excursion of the optimal path beyond the boundaries approach zero, thus deriving the optimal control condition. The main results of the paper are stated in the form of two theorems. Also considered is the practical significance of the results for systems with multiple saturation.

This paper deals with the solution of optimum control problems, using Pontryagin's maximum principle. Since an optimum control system which completes the transient response in minimum time behaves like a relay servo, the important task of the controller is to reverse the sign of the manipulated variable at the proper instants according to the operating condition of the system. A set of points at which the sign of the manipulated variable is to be reversed forms a switching surface in the phase space. In this paper the optimum switching surface of a linear third-order system is investigated. Also dealt with is the optimum switching curve of a non-linear control system governed by van der Pol's equation with an additional forcing term.

In this paper some new results concerning analysis and synthesis of time-optimal control systems are given. We assume that the motion of the controlled plant is described by linear ordinary differential equations with variable or constant coefficients, and the final states of the system form a convex region of phase space. Geometric properties of the isochronous region of these systems in phase space and the facts connected with these which have fundamental meaning for the solution of the synthesis problem are discussed. Moreover the facts demonstrated which are formulated in theorems have also their independent interests. At the end of this paper is given the method of synthesis of the optimal control function for constant as well as with variable coefficients, and illustrative examples.

This paper unifies and extends the ideas and techniques used by the authors in relation with the minimal time regulator problem. The system considered is a multiple input system described by a differential equation of the form $ = F(x) + Bu(t) where u is either a PAM or PWM bounded control vector. This paper consists of five sections. In the first, the problem is carefully stated in a suitable general setting, and the concept of optimal strategy is defined; in the second, an optimal strategy for a multiple input PAM system with a completely controllable linear plant is described fully, and a special case is discussed; in the third, the concept of equivalent optimal strategies is defined, and sufficient conditions for equivalence are indicated. In the fourth section equivalence is used to derive the optimal strategy of a PWM system whose linear plant has real and distinct eigenvalues, and finally in the last section, some extensions are mentioned.

The purpose of this paper is to investigate the optimum design of predictor control systems subject to statistical or deterministic inputs, under appropriate constraints on the control signal. The control signal constraints treated in this paper are: (a) the magnitude of the control signal equal to a constant (this is the bang-bang control problem), and (b) the magnitude of the control signal less than or equal to some constant.

The paper is dealing with sampled-data control system with variable structure. These structural changes are carried out by switching of the width of the pulses given by the holder. The present paper, unlike former works, is investigating the influence of the input signal on the dynamics of the control system. The conditions for the switching instant under chosen criterion are derived by using of appropriate approximation of the input signal. The simple decision link carrying out this activity is designed. This decision link is also duly operating with the sample of the input signal so that the adaptivity to this signal is ensured. The practical examples are demonstrating the behavior of the control systems with various plants exposed to various input signals.

This paper describes the adaptive methods to construct the optimal switching curves used for time optimal control of second order processes. Three types of adaptive pattern classifiers can be used, i.e.(1) gradient-variable piecewise linear, (2) zone-variable piecewise linear and (3) non-linear pattern classifiers. The adaptation logic introduced in this paper is based on the time course of geometrical relation between the state point and the switching curve in the state plane of the process and can be applied to the processes at work. The methods need neither a priori information of the process nor identifying it. Besides they are likewise applicable to both linear and nonlinear processes. It is shown that are arbitrary switching curve is adaptively optimalized, and that by the iterative application of this on-line adaptation, approximated optimal control can be realized.

The paper describes the principles suggested for a system for control of the movement of a school of fish in the ocean. A mathematical model using state space notation is developed, describing how the movement of a school is related to natural and artificial stimuli. Different kinds of natural and artificial stimuli are discussed and different ways of determination of direction in scalar and vector fields of stimuli are described. A mathematical expression is derived showing that the sensitivity of directional navigation of a large school is nearly proportional to the number of individuals in the school. A control structure is suggested using feed-back control stimuli from measured and estimated states of the school movement. The paper concludes with a survey of some practical applications of the techniques suggested in nerding of pelagic fish.

This work deals with a special case of a more general problem the treatment of which has been begun with a paper presented at the IVth IFAC-Congress at Warsaw and has been continued with an additional paper; in these papers physical conditions in a channel which gas is flowing through and heated by a heat flux varying along the flow direction were described by the onedimensional conservation equations of mass, momentum and energy; further the equation of state of ideal gases was used. Stationary equations could be solved easily; linearization of the nonlinear time-dependent equations resulted in the dynamics of small perturbations of stationary states. On this occasion it was found that also an analytical treatment of this problem even for the case where the heat flux does not vary along the channel is rather extensive and difficult; on the example of perturbations of a trans-sonic stationary state it was demonstrated how simplifications of calculations can be achieved. This paper applies the same method on the perturbations of a stationary state with entrance Mach number Me< 10-1. From the point of view of control theory it is an identification problem of a system with one dimensionally distributed parameters, i.e. one dimension of the physical structure exceeds in its extension by orders of magnitude the other two dimensions so that in these two dimensions variation of parameters can be neglected what in addition has the mathematical advantage that the boundary value problem associated with the boundary control problem can be solved without difficulties.