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Non-PR, IFPRI5, EPTD

"October, 1982.", Bibliography: p. 1022-1023., Contract F33615-77OC-3096 NASA/Ames Grant NGL-22-009-124, by Timothy L. Johnson, Charles A. Harvey, Gunter Stein.

"October, 1982.", Bibliography: p. 1022-1023., Contract F33615-77OC-3096 NASA/Ames Grant NGL-22-009-124, by Timothy L. Johnson, Charles A. Harvey, Gunter Stein.

Bibliography: p. 7., "April, 1981"--report documentation page. "20th CDC.", U.S. Air Force Office of Scientific Research contract F49620-80-C-0002, Timothy L. Johnson.

Bibliography: p. 7., "April, 1981"--report documentation page. "20th CDC.", U.S. Air Force Office of Scientific Research contract F49620-80-C-0002, Timothy L. Johnson.

Interim report., "June 8, 1981.", Bibliography: leaf 3., AFOSR Contract F49620-80-C-0002, Timothy Johnson, Martin E. Kaliski.

Final Technical Report., Bibliography: leaf 17a., Prepared for Air Force Office of Scientific Research Contract F49620-80-C-0002., Timothy L. Johnson, Martin E. Kaliski.

Bibliography: p. 7., "April, 1981"--report documentation page. "20th CDC.", U.S. Air Force Office of Scientific Research contract F49620-80-C-0002, Timothy L. Johnson.

Bibliography: p. 6., "April, 1981.", U.S. Air Force Office of Scientific Research contract F49620-80-C-0002, D.G. Wimpey, T.L. Johnson, M.E. Kaliski.

Bibliography: p. 7., "April, 1981"--report documentation page. "20th CDC.", U.S. Air Force Office of Scientific Research contract F49620-80-C-0002, Timothy L. Johnson.

Bibliography: leaf [5], "April, 1981", "U.S. Air Force Office of Scientific Research ... Contract No. F49620-80-C-0002", T.L. Johnson.

Interim report., "June 8, 1981.", Bibliography: leaf 3., AFOSR Contract F49620-80-C-0002, Timothy Johnson, Martin E. Kaliski.

Bibliography: p. 7., "April, 1981"--report documentation page. "20th CDC.", U.S. Air Force Office of Scientific Research contract F49620-80-C-0002, Timothy L. Johnson.

Bibliography: p. 6., "April, 1981.", U.S. Air Force Office of Scientific Research contract F49620-80-C-0002, D.G. Wimpey, T.L. Johnson, M.E. Kaliski.

Bibliography: p. 7., "April, 1981"--report documentation page. "20th CDC.", U.S. Air Force Office of Scientific Research contract F49620-80-C-0002, Timothy L. Johnson.

Bibliography: leaf [5], "April, 1981", "U.S. Air Force Office of Scientific Research ... Contract No. F49620-80-C-0002", T.L. Johnson.

Final Technical Report., Bibliography: leaf 17a., Prepared for Air Force Office of Scientific Research Contract F49620-80-C-0002., Timothy L. Johnson, Martin E. Kaliski.

Most explosives that occur as groundwater pollutants at DoD sites are nitro aromatic compounds (TNT, trinitrobenzene, and various di- and mono-nitrotoluenes) or nitramines (RDX, HMX, and Tetryl). Under favorable conditions, nitro aromatic compounds (NACs) react rapidly with zero-valent iron (Fe0), which suggests that permeable reactive barriers containing zerovalent iron (FePRBs) might be useful in the remediation of groundwater contaminated with explosives. Unfortunately, reduction of NACs by iron metal produces aromatic amines as the primary products, and these products are still substances of regulatory concern. As a result, fullscale implementation of FePRBs to treat explosives contaminated groundwater has been delayed until an effective treatment for the amines has been developed and tested. The goal of this project was to develop an oxidative treatment step to treat the products of nitro reduction, so that the combination would form a sequential reactive treatment zone (SRTZ) that could be used to reach treatment goals for TNT-contaminated groundwater under field conditions. To generate simulated effluent from an FePRB we prepared bench scale columns, packed initially with 100% construction-grade, granular iron metal. We found that 100% iron columns, even at flow rates as high as 125 ft/day, produced no TNT or degradation products. Some of the columns were operated for 1600 pore volumes with no TNT or any reaction products detected (by HPLC) in the effluent. The capacity of these columns to reduce TNT and sequester all of the reduction products suggested that simple FePRBs (with out the additional treatment zones associated with an SRTZ), might be sufficient for full-scale remediation of TNT-contaminated groundwater.

Asynchronous multitask processes occur in a wide variety of control applications ranging from industrial control to computer operating systems, yet no analytical methods are available for studying their detailed behavior. The preliminary results reported here illustrate that a very general class of such processes can be represented by discontinuous hybrid-state discrete-time systems. (Author), Presented at the IEEE Conference Decision and Control (20th), San Diego, CA, Dec 81.

The application of a functional expansion technique introduced by Bellman to the determination of nonlinear optimal control laws is described. For a certain class of 'smooth' control problems, it is demonstrated that convergence of the expansion technique may be improved by use of a nonlinear (rather than linear) auxiliary equation which is based on a known cost-to-go function for an associated 'linear-quadratic' optimal control problem. (Author)

This paper presented two results: a new structure for the solution of nonlinear analytic systems, and an application of Bellman's Fundamental Technique to obtain the sub-optimal-feedback control of a class of quasilinear systems with non-quadratic performance indices. The application of the Fundamental Technique with a nonlinear auxiliary equation is shown to result in higher order approximating equations which are linear. Using the method by separation of variables, two examples are solved. (Author)

Uncertain elements must be considered in the mathematical model of many dynamical systems. The theory associated with additive noise models is quite advanced, but many control problems are more realistically modeled as containing uncertain and time varying parameters or gains. For multiplicative gains of the white noise type, necessary and sufficient conditions for the stability of many of these systems have been derived previously. In this article, we develop conditions for the stability of some continuous-time systems containing multiplicative colored noise., Prepared in cooperation with Raytheon Co., Bedford, Mass.

Canonical realization and synthesis of synchronous coders (mappings of real-valued input sequences to discrete-valued output sequences) have been achieved. Equivalent characterization of such coders as mappings, hybrid automata and real language acceptors have been established. Practical device synthesis procedures have been given for a significant class of such mappings. Regularity results have been developed for more general classes of coders. Algorithms for control design of synchronous systems with piecewise-continuous transition mappings, which employ new aggregation results along with the foregoing synthesis results have been derived. Unlike previous methods, these algorithms encompass coder/decoder specification and produce designs which are directly implementable as automata. Preliminary results have been obtained for asynchronous coders and controllers. It has been shown that a certain class of asynchronous multitasking systems admit realization as hybrid synchronous systems and are hence amenable to the methods of analysis developed for synchronous control systems. The concepts employed for synchronous coders may be generalized to the asynchronous case, but the specific form of the results differs. Qualitative properties of a class of piecewise-constant systems have been established. (Author)

The study pertains to the development of automated techniques for classification of vectorcardiograms and electrocardiograms using signal analysis techniques. A data preprocessor is developed to produce an average heartbeat from a record containing multiple heartbeats corrupted by severe baseline shifts. Several techniques for generating an ECG/VCG transformation are studied. Individual transformations are found to be quite accurate, if phase shifts among the leads are taken into account. However, patient variability appears to preclude use of a standardized transformation. The structure of the data base required to accurately test the classification algorithms is discussed and specific recommendations are made. The effect of using both two- and three-dimensional coordinate systems and a normalizing transformation for feature generation was studied; classification accuracy remained essentially unchanged., Sponsored in part by School of Aerospace Medicine, Brooks AFB, Tex.

The paper considers the problem of designing compensators for linear systems whose dimensionality is fixed a priori. Two types of compensators are considered. First static (gain only) compensators that operate directly upon the output signals to generate the controls and, second, dynamic compensators of fixed dimension. The equations that define the parameters of such compensators are developed. (Author), Sponsored in part by Grant NSF-GK-25781, and NSF-GK-5315.

The paper deals with the design of linear time-invariant dynamic compensators of fixed dimensionality (s) which are to be used for the regulation of an n-th order linear time-invariant plant. A modified quadratic cost criterion is employed in which a quadratic penalty on the system state as well as all compensator gains is used; the effects of the initial state are averaged out. The optimal compensator gains are specified by a set of simultaneous non-linear matrix algebraic equations. The numberical solution of these equations would specify the gain-matrices of the dynamic compensator. The proposed method may prove useful in the design of low-order (s) compensators for high-order (n) plants that have few (r) outputs, so that the dimension of the compensator is less than that obtained through the use of the associated Kalman-Bucy filter (n) or Luenberger observer (n-r). (Author), Sponsored in part by National Aeronautics and Space Administration, Grant NGL-22-009(124).