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This paper presents a procedure which is used to identify the coefficients of a nonlinear polynomial model for an air-to-air missile. The structure of the polynomial model is determined using the Group Method of Data Handling (GMDH) algorithm with a data base consisting only of values for input-output variables. The GMDH algorithm generates a network of smaller nonlinear polynomial kernels as its...
This paper presents a procedure for improving the feedback properties of a linear multivariable state feedback system which was designed using linear quadratic optimization. The procedure adjusts the quadratic weights using information obtained from a singular value analysis of the closed loop system. Although attention is focused primarily on the linear quadratic design method, the basic approach...
Process control by distributed intelligence, commonly known as distributed and hierarchical control, has developed over the last few years as a natural outcome of the need to separate control functions by Process Area and Level of Control, while maintaining overall system security and simplicity of operation. This paper describes its evolution and illustrates its implementation in the cement industry...
A plant P(s) is represented by an N??N matrix of frequency responses. It is shown that if P-1(s) is analytic in Re(s) ?? 0, P(s) approaches diagonal dominance at high frequencies, and P(s) satisfies an attenuation condition at high frequencies, then it is possible to make sensitivity arbitrarily small without violating a global sensitivity bound by means of a diagonal feedback. The result is then...
The paper presents a design algorithm for the control system utilizing theory of heirarchical controls, but extending the decomposition and coordination method.
Stoker boilers are a class of boilers in which a solid fuel, such as coal or bark, is burned in suspension as well as on a grate. Air is admitted both under and over the fuel grate. In order to achieve an optimum combustion efficiency the presented control scheme uses steam flow, fuel flow, CO, CO2 and opacity measurements for distribution of the under-grate and overfire air-flows. The control scheme...
Two parametrical optimization problems are defined in order to try to improve the stability conditions given by the scalar approach and the vectorial approach of the Lyapunov method for interconnected systems. An approximate solution is provided in the vectorial case, and discussed with respect to previous works. The paper ends on a critical discussion of the Lyapunov approach in the decentralized...
A dynamic lime kiln simulation model has been developed and validated by extensive test data from pulp mill lime kilns. The simulation is used to evaluate control and equipment requirements during transient or upset conditions. Control strategies and equipment, or kiln subsystem modifications can be perfected and implemented with a high degree of confidence in rapid installation and startup. This...
This paper describes the results of a study of the application of a multivariable self-tuning controller to stabilize the temperature profile throughout a dolomite kiln. Simulations of the two input, two output, indirect self-tuning controller on a transient model of the kiln were performed. A first principle model was used in this study to simulate the behavior of the dolomite kiln. The method used...
This paper investigates the problem of synthesis of decentralized output/state regulators for large scale systems. The decentralized regulators are synthesized by salving-the extended algebraic Riccati equation (EARE). Three different methods are proposed for the solution of the EARE. One of the methods uses decomposition to solve the EARE. This results in a hierarchical scheme of the coordinator...
The failure analysis of the fluidized bed process. Its implementation into the control system. The system's internal safety checking system and protection. This is to include final devices, hard wired backup and interface systems, high speed multiplexer, dual CPUs, controlled and uncontrolled processs shutdowns, and intrasoftware monitoring systems.
A graph-theoretic characterization of structurally fixed modes of large-scale systems under feedback structure constraints is given. The characterization allows for a quick and reliable test for detecting the existence of those fixed modes that arise due to a special structure of the system. The test can be used at the first stage of the design problem before a quantitative analysis of the system...
The processing of iron-ore to form sinter is a complex metallurgical process carried out on a moving grate. The production rate of good quality sinter is affected by significant variations in the properties of the raw input materials and in operating conditions. In large production units the emphasis is on overall steadiness of the process and the sinter strand is driven at constant speed for long...
A new scheme for designing model reference adaptive control systems using only input and output measurements is presented. With the proposed scheme, the requirement on the commonly assumed a priori knowledge of (i) the relative degree n* of the plant and (ii) sign of the high frequency gain, can be eliminated. Besides the elimination of requirement of the two restrictive assumptions, the proposed...
This paper deals with a self-tuning control strategy for handling systems in which the output data may be lost temporary. The self-tuning algorithm is a modified version of the usual set up which consists of on-line identification and control. Output estimation will be needed when the output data is not available. The output estimates can be updated rapidly while no updating for the parameter estimates...
This paper presents a model reference adaptive system (MRAS) using Liapunov synthesis applied to a nonlinear oscillator to achieve adaptive control. By considering important properties of the reference model describing a nonlinear oscillator it is possible to manipulate the mathematical equation of the adapted oscillator to derive the error-equation in a form which is linear in the state variables...
A new technique for tracking a maneuvering target in a cluttered environment is developed. This approach does not rely on a statistical description of the maneuver as a random process. Instead, the state model for the target is changed when a maneuver is detected. Undesired measurements due to clutter or false alarms are assumed to occur uniformly and independently distributed. The Probabilistic Data...
This paper presents an output model reference tracking algorithm based on a simple augmentation of the tracking error. The controlled plant is able to track the output of a reference model for input commands, such as polynomials, which can be generated by a linear system, pending satisfaction of a stability condition.
The Office of Naval Research (ONR) program in decision and control systems has two major components. The first is in the area of centralized control and responds to Naval needs in vehicle and weapon control. The second is in large scale systems and is concerned with naval applications in surveillance, command and control, and communications. The research is strongly problem motivated but spans both...
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