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Routh Approximation Method (RAM) is a very useful technique for reducing the order of a linear systems and for evaluating the suboptimal control policies for the large scale systems. This method does not require a knowledge of system eigenvalues and eigenvectors and possesses many desirable features such as preservation of reduced order model stability and minimum computational requirements. A modified...
This paper describes work currently being undertaken on the problem of applying optimal control techniques to developing decentralized optimal routing algorithms for a saturated packet-switched computer communication network.
Although the root-loci of linear multivariable systems have many of the characteristics of there classical counterparts, there are a number of essentially multivariable possibilities that require careful identification. It is shown here that classical characteristics are generic in a carefully defined and very important sense and thatnon-generic behaviour only occurs in bad design conditions.
Considerable theoretical advances have been made in the application of Computational Complexity theory (CCT) to some very basic digital signal processing calculations such as the computation of multilinear forms, convolutions, and the Discrete Fourier Transform (DFT). These are particularly useful in digital signal processing where typically, the amount of data is large and, in some cases, must be...
The formulation of the decision making of a failure detection process as a Bayes sequential decision problem (BSDP) provides a simple conceptualization of the decision rule design problem. As the optimal Bayes rule is not computable, a methodology that is based on the Baysian approach and aimed at a reduced computational requirement is developed for designing suboptimal rules. A numerical algorithm...
Computer control and supervisory systems often monitor large numbers of signals. Conventionally a scanner is used to switch signals one by one to the computer, and the inefficiency of this procedure is a major operational and cost barrier. For example in scanning 1000 signals on a plant les than 1% on average show unexpected changes and 99% of the data is rejected. Signal conditioning times exceed...
The development of numerous methods for automatically diagnosing faults in complex systems leads naturally to the design problem of choosing the best method and the best design parameters for a particular system. This paper addresses the problem of efficiently evaluating the performance of systems which include automatic fault diagnostics. The analytical methods discussed rely on the construction...
Orbital forging is a unique metalforming process that requires forces much smaller than conventional forging. Because of this is has the potential of producing high precision parts. It is also amenable to the application of numerical (NC) and adaptive (AC) controls. In this paper a model of the orbital forging process that gives an estimate of the part accuracy as a function of material, part design,...
This paper deals with the block partial fraction expansion of a matrix transfer function F(s), where F(s) = Nr(s)Dr-1(s) = Dl-1(s) and Nr(s), Dr(s), Dl (s) and Nl (s) are ??-matrices with matrix coefficients. A new algorithm is derived to construct a transformation matrix that transforms a right (left) solvent to the corresponding left (right) solvent of a matrix polynomial. Also, the algorithm can...
A valve controlled ram type servosystem employing position feedback with an electrohydraulic servovalve is modelled to simulate with a digital computer all of the possibly significant physical characteristics of such a system, including turbulent flow in connecting passages, and Coulomb-type friction as well as supply line dynamics. The simulated responses are compared with corresponding measured...
Recent development of an interactive computer technique aids meteorologists in using geostationary satellite imagery to estimate precipitation. The interactive technique utilizes the interpretive abilities and experience of the meteorologist with the speed and accuracy of the computer to reduce the time and effort required by the previously developed manual method. An analysis of a precipitation event...
Gates Learjet Corporation has utilized parameter identification techniques on flight test data in various ways to substantiate the airloads analyses used in certifying its airplanes. These analyses have concentrated primarily on the empennage and include: horizontal stabilizer rolling moment; vertical tail side load; horizontal tail actuator load; elevator, rudder and aileron pilot forces; and elevator...
Remotely sensed digital data (Landsat CCT) has proven an efficient and cost effective means of defining land cover information required in hydrologic modeling. However, an organization such as a county government finds great difficulty in collecting and integrating regional ancillary data (aerial photos, soils) with digital remote sensed data. A computer-based information system allowing engineers...
Several maximum likelihood and multiple regression parameter estimation programs are currently being used at the Langley Research Center of the NASA to analyze aircraft flight test data. Based on this wealth of experience, the pertinent features of these programs are investigated and some of the difficulties involved in their use are discussed. By comparing computational time, data requirements and...