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An airborne digital computer is used to estimate gun misalignment, ballistic wind and wind at altitude. The navigator interacts with the computer in making decisions as to whether observed data is reliable and whether certain parameters in the computer should be changed. The use of this system still retains human judgment while at the same time gives the navigator the power of digital computation.
The problem of optimal control of a nonlinear system with non quadratic final cost function admits a closed-loop suboptimal solution by approximation of the Lyapounov function by means of the control-equivalent Gaussian sum method. Using the duality between optimal control for deterministic systems and estimation for stochastic systems, the solution is presented as the superposition of solutions of...
A class of singular quadratic minimization problems is examined by reducing the performance index to a quadratic form in the control variable. A necessary and sufficient condition for minimality is that the kernel of this quadratic form be non-negative definite, or equivalently, be a covariance kernel (function). Various properties of such functions are then used to obtain different sets of necessary...
The well-known Routh and Jury tabular schemes for determination of linear system zero location relative to the left half plane and unit disc respectively are formulated as special cases of two algorithms for finding the greatest common divisor of two polynomials. Two recent extensions of the tabular methods are expressed similarly, and this enables a previously unknown 'duality' property of the two...
For a constant linear dynamic system with unmeasurable disturbances, geometric necessary and sufficient conditions are derived for the existence of a state-feedback controller that localizes the disturbances and simultaneously assigns the closed-loop poles or decouples the closed-loop system. These conditions are simple, intuitively appealing, and closely related to the known necessary and sufficient...
This paper introduces a measure of the ability for a pattern classifier to discriminate among different pattern classes. The use of this measure then defines a compromise between pattern discrimination and recognition error. The measure is particularly useful in sequential pattern classification in allowing control of discrimination level versus recognition error. The trade-off between discrimination...
Linear and nonlinear adaptive algorithms for coping with intersymbol interference and additive noise in high speed data transmission over time-dispersive channels are presented. The algorithms perform the signal detection function and simultaneously, either directly or indirectly, estimate the channel for the purpose of identifying the characteristics of the inter-symbol interference. The stability...
The convergence rates of descent methods with different stepsize rules are compared. Among the stepsize rules considered are: constant stepsize, minimization along a line, Goldstein-Armijo rules, and stepsize equal to minimum of certain interpolatory polynomials. One of the major results shown is that the rate of convergence of descent methods with the Goldstein-Armijo stepsize rule can be made as...
This paper attempts to survey our knowledge, and the practical scope of our use of, the method of conjugate gradients and its close relatives in the numerical solution of problems of quadratic and nonquadratic optimization.
The performance of hybrid navigation systems for commercial transoceanic flights is evaluated by means of a digital computer simulation. Error models are developed for aided-inertial navigation systems with external measurements from Doppler radar, Omega and satellite-ranging. Key features of the simulation program AIRNAV (Aided-Inertial Reference NAVigation) are described. Covariance matrix error...
Pattern recognition and its application to ocean surveillance and the near-real-time screening of tactical reconnaissance imagery presented to the pilot were chosen as a typical adaptive systems project in the Navy. The performance of a pattern-recognition device is compared with that of a human operator. It is concluded that the human operator will make the final decision, but he will be aided by...
Practical and theoretical aspects of the use of spline functions in approximately solving open-loop optimal control problems are surveyed. It is shown how B-splines can be used to yield highly structured and sparse discrete approximations to the continuous problem; some computational methods useful on the resulting discrete problems are mentioned. The question of the accuracy obtainable by such methods...
The linear stochastic realization problem for a time-varying process with a smooth separable covariance is briefly described. It is shown that finding all Markovian realizations of the process is equivalent with finding all solutions to a set of constraints on the state-variances. Introducing a partial ordering on this set of nonnegative definite solutions [viz., ?1 ? ?2 if ?1 - ?2 is nonnegative...
Described in this paper is an application of variable structure stochastic automata to the solution of the hypothesis testing problem. Given the upper bounds on the error probabilities of the two kinds a design procedure for devising an algorithm for the stochastic automaton which ensures a proper decision is developed. The method is illustrated by an application to a simple detection problem of a...
A very important class of problems deals with the control of systems whose structure can undergo changes. The simplest class of changes are the ones that affect only the system parameters and not the rest of the basic structure of the system like order. In this paper we examine the class of linear, discrete time, multiple-input multiple-output systems, with additive system disturbances and exact output...
A point set with a partial order (poset) P is a useful "generalized time" set for linear system theory, since the fundamental concept of causality can be defined for linear operators on a function space on P. The causal-operator algebra has a rich structure, known to combinatorists. Specializing to posets which admit shift operators, some novel generalizations of time-invariance are obtained;...
Sufficient conditions for the stability of self-organizing control algorithms based on a subgoal approach are given. A method is presented which aids in the a-priori choice of the structure of the feedback control law under the assumption that on-line or off-line identification of the structure of the plant has been accomplished. Subsequent to closing the loop, bounds, which depend on the control...
This paper starts with a brief review of the syntactic (linguistic) approach to pattern recognition. One-dimensional and high dimensional languages for pattern description and recognition are domenstated by application examples. Several problems motivated by practical applications of syntactic pattern recognition are discussed. In applying syntactic approach to pattern recognition problems, abstract...
The application of Kalman-Bucy filters entails precise knowledge on the a priori noise covariances as well as the system parameters. In many practical cases, however, such precise knowledge is not available, and approximate values are usually used or assumed. It has been pointed out that incorrect covariances often cause severe inconsistency between the calculated error covariance and the actual one...
A generalized Bush-Mosteller learning model is discussed simulating both finite memory range learning and infinite memory range imprinting processes, as well as an ideal learning scheme storing all experiences with equal weight. The learning and imprinting dynamics in stationary and non-stationary environments is studied using as a performance criterion the relative entropy of the true with respect...
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