Detection of changes in the characteristics of a Gauss-Markov process.
Sequential probability ratio test for detecting changes in Gauss-Markov process characteristics, noting application to fault detection in gyro navigational system
Ho, Y.-C.↗
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Statistical equilibrium and ergodic Markov chains.
Time dependent statistical equilibrium equations solutions for describing time development of atomic populations by means of ergodic Markov chain
Dietz, R. D.↗
Probability learning - First-order Markov structures of quarternary events
First order Markov structures of quaternary events applied to probability learning
Huff, E. M.↗
Accelerated procedures for the solution of discrete Markov control problems Final report
Accelerated procedures for solution of discrete Markov control problems
Kleinman, A. J.↗
Mathematical programming and the control of Markov chains
Linear and dynamic programming and Markov chain optimal control
Kleinman, A. J.↗
Identification of a transition matrix of a Markov chain from noisy measurements of state
Transition matrix of Markov chain with finite states from noisy measurements of state, discussing algorithms convergence rates and computations
Kashyap, R. L.↗
Accelerated procedures for the solution of discret e Markov control problems
Accelerated procedures for Markov chain model optimal control problems solution with computation time advantage over usual dynamic programming
Kleinman, A. J.↗
A study of the Markov game approach to tactical maneuvering problems
Application of Markov game approach to planar air combat problems
Baron, S.↗
A Markov chain technique for determining the acquisition behavior of a digital tracking loop
An iterative procedure is presented for determining the acquisition behavior of discrete or digital implementations of a tracking loop. The technique is based on the theory of Markov chains and provides the cumulative probability of acquisition in the loop as a function of time in the presence of noise and a given set of initial condition probabilities. A digital second-order tracking loop to be used in the Viking command receiver for continuous tracking of the command subcarrier phase was analyzed using this technique, and the results agree closely with experimental data.
Chadwick, H. D.↗
Application of Markov chain theory to ASTP natural environment launch criteria at Kennedy Space Center
To aid the planning of the Apollo Soyuz Test Program (ASTP), certain natural environment statistical relationships are presented, based on Markov theory and empirical counts. The practical results are in terms of conditional probability of favorable and unfavorable launch conditions at Kennedy Space Center (KSC). They are based upon 15 years of recorded weather data which are analyzed under a set of natural environmental launch constraints. Three specific forecasting problems were treated: (1) the length of record of past weather which is useful to a prediction; (2) the effect of persistence in runs of favorable and unfavorable conditions; and (3) the forecasting of future weather in probabilistic terms.
Graves, M. E.↗
A Markov model for X-band atmospheric antenna-noise temperatures
A five-state Markov model is suggested for the X-band antenna-noise temperatures based on data collected at Goldstone. The states of the model are determined by changes in the cloud and rain condition of the atmosphere so as to take advantage of the correlation observed between the antenna temperatures and changes in rain rates. Then an indication is given of how to obtain the estimates of the parameters of the model from the data.
Adeyemi, O. H.↗
Determination of navigation FDI thresholds using a Markov model
A method for determining time-varying Failure Detection and Identification (FDI) thresholds for single sample decision functions is described in the context of a triplex system of inertial platforms. A cost function consisting of the probability of vehicle loss due to FDI decision errors is minimized. A discrete Markov model is constructed from which this cost can be determined as a function of the decision thresholds employed to detect and identify the first and second failures. Optimal thresholds are determined through the use of parameter optimization techniques. The application of this approach to threshold determination is illustrated for the Space Shuttle's inertial measurement instruments.
Walker, B. K.↗
Optimum equipment maintenance/replacement policy. Part 2: Markov decision approach
Dynamic programming was utilized as an alternative optimization technique to determine an optimal policy over a given time period. According to a joint effect of the probabilistic transition of states and the sequence of decision making, the optimal policy is sought such that a set of decisions optimizes the long-run expected average cost (or profit) per unit time. Provision of an alternative measure for the expected long-run total discounted costs is also considered. A computer program based on the concept of the Markov Decision Process was developed and tested. The program code listing, the statement of a sample problem, and the computed results are presented.
Charng, T.↗
Upper and lower bounds for semi-Markov reliability models of reconfigurable systems
This paper determines the information required about system recovery to compute the reliability of a class of reconfigurable systems. Upper and lower bounds are derived for these systems. The class consists of those systems that satisfy five assumptions: the components fail independently at a low constant rate, fault occurrence and system reconfiguration are independent processes, the reliability model is semi-Markov, the recovery functions which describe system configuration have small means and variances, and the system is well designed. The bounds are easy to compute, and examples are included.
White, A. L.↗
The semi-Markov unreliability range evaluator program
The SURE program is a design/validation tool for ultrareliable computer system architectures. The system uses simple algebraic formulas to compute accurate upper and lower bounds for the death state probabilities of a large class of semi-Markov models. The mathematical formulas used in the program were derived from a mathematical theorem proven by Allan White under contract to NASA Langley Research Center. This mathematical theorem is discussed along with the user interface to the SURE program.
Butler, R. W.↗
Power spectral ensity of markov texture fields
Texture is an important image characteristic. A variety of spatial domain techniques were proposed for extracting and utilizing textural features for segmenting and classifying images. for the most part, these spatial domain techniques are ad hos in nature. A markov random field model for image texture is discussed. A frequency domain description of image texture is derived in terms of the power spectral density. This model is used for designing optimum frequency domain filters for enhancing, restoring and segmenting images based on their textural properties.
Shanmugan, K. S.↗
An abstract specification language for Markov reliability models
Markov models can be used to compute the reliability of virtually any fault tolerant system. However, the process of delineating all of the states and transitions in a model of complex system can be devastatingly tedious and error-prone. An approach to this problem is presented utilizing an abstract model definition language. This high level language is described in a nonformal manner and illustrated by example.
Butler, R. W.↗
Performance evaluation of fault tolerant systems represented by Markov models
A method to evaluate the performance of fault tolerant systems whose configuration can be represented by time-invariant, discrete-time, discrete-state Markov models is introduced. Each state is assumed to be associated with a constant qualitative measure of the system's performance. The method first computes the moments of the performance probability mass function (PMF) and then finds an approximating function that has the same moments. The form of this function is a maximum entropy solution of the moment matching problem. A simple algorithm for calculating the necessary moments is derived and a method for finding the approximate performance PMF is suggested. After some modification, the method is applied to an example, the Inertial Upper Stage navigation system.
Missana, Jean-Olivier A. A.↗