*This section will contain thematic groupings of selected papers and pdfs for download for prompt dissemination. Copyrights are held by publishers and/or the authors.*

Interactions amongst agents leading to collective behavior is a theme of these papers. Applications suggest models of particles subject to interactions based on gyroscopic forces. Moving frames and geometric methods are useful in the analysis of such models. A special class of interactions of interest is pursuit (and avoidance). Pursuit is a familiar mechanical activity that humans and animals engage in (e.g. athletes chasing balls, predators seeking prey, insects maneuvering in aerial territorial battles). We examine different pursuit strategies, and a possible role for such strategies as building blocks for coherent structures (flocks, swarms, schools, etc).

E. W. Justh and P. S. Krishnaprasad (2002). A simple control law for UAV formation flying, Institute for Systems Research Technical Report, TR 2002-38, 35 pages.

E. W. Justh and P. S. Krishnaprasad (2003). Steering Laws and Continuum Models for Planar Formations, Proc. 42nd IEEE Conference on Decision and Control, pp 3609-3614, IEEE, New York.

E. W. Justh and P. S. Krishnaprasad (2004). Equilibria and Steering Laws for Planar Formations Systems and Control Letters, vol. 52, no. 1, pp. 25-38.

E. W. Justh and P. S. Krishnaprasad (2005). Natural Frames and Interacting Particles in Three Dimensions Proc. 44th IEEE Conference on Decision and Control, pp. 2842-2846, IEEE, New York.

K. Ghose, T. K. Horiuchi, P. S. Krishnaprasad and C. F. Moss (2006). Echolocating Bats use a Nearly Time-optimal Strategy to Intercept Prey PLoS Biology, 4, 865-873, e. 108.

E. W. Justh and P. S. Krishnaprasad (2006). Steering Laws for Motion Camouflage Proceedings of the Royal Society of London A, 462, 3629-3643.

P. V. Reddy, E. W. Justh and P. S. Krishnaprasad (2006). Motion Camouflage in Three Dimensions Proc. 45th IEEE Conference on Decision and Control, pp. 3327-3332, IEEE, New York.

P. V. Reddy, E. W. Justh and P. S. Krishnaprasad (2007). Motion Camouflage with Sensorimotor Delay Proc. 46th IEEE Conference on Decision and Control, 1660-1665, IEEE, New York.

K. S. Galloway, E. W. Justh and P. S. Krishnaprasad (2007). Motion Camouflage in a Stochastic Setting Proc. 46th IEEE Conference on Decision and Control, 1652-1659, IEEE, New York.

E. Wei, E. W. Justh and P. S. Krishnaprasad (2009). Pursuit and an Evolutionary Game Proceedings of the Royal Society of London A, 465, 1539-1559.

K. Galloway, E. W. Justh and P. S. Krishnaprasad (2009). Geometry of Cyclic Pursuit Proc. 48th IEEE Conference on Decision and Control, 7485-7490, IEEE, New York.

M. Mischiati and P. S. Krishnaprasad (2010). Motion Camouflage for Coverage, Proc. American Control Conference, pp. 6429-6435, American Automatic Control Council, Philadelphia.

C. Chiu, P. V. Reddy, W. Xian, P. S. Krishnaprasad, and Cynthia F. Moss (2010). Effects of competitive prey capture on flight behavior and sonar beam pattern in paired big brown bats, Eptesicus fuscus, The Journal of Experimental Biology, Vol. 213, Issue 19, 3348-3356.

K. S. Galloway, E. W. Justh and P. S. Krishnaprasad (2010). Cyclic Pursuit in Three Dimensions, 7141-7146, IEEE, New York.

E. W. Justh and P. S. Krishnaprasad (2010). Extremal Collective Behavior, 5432-5437, IEEE, New York.

E. W. Justh and P. S. Krishnaprasad (2011). Optimal Natural Frames, Communications in Information and Systems, Vol. 11, No. 1, pp. 17-34 (published online (october 2010)

The structures of geometric mechanics, including symplectic and poisson structures, symmetry and reduction, momentum maps and connections, and lagrangian systems with nonholonomic constraints, form the basis of these papers. Special solutions such as relative equilibria, periodic orbits, their stability and bifurcations are investigated. Role of feedback in stabilization and preservation of structures is examined in a variety of settings, including gyroscopic Lagrangians, inspired by applications in aerospace systems. The models analyzed range from examples in finite dimensional solid mechanics such as gyrostats, to elastodynamics, rigid bodies interacting with fluids, and wheeled vehicles in robotics. The notion of geometric phase and associated optimal control problems are investigated. Dissipation mechanisms and instabilitiess are studied from a geometric viewpoint.

P. S. Krishnaprasad (1979). Symplectic Mechanics and Rational Functions, Richerche di Automatica, vol. 10, no. 2, pp. 107-135.

M. El-Baraka and P. S. Krishnaprasad (1984).Geometric Methods for Multibody Dynamics, AIAA Dynamics Specialists Conference, pp. 607-615, AIAA, New York.

P. S. Krishnaprasad (1985). Lie-Poisson Structures, Dual-Spin Spacecraft and Asymptotic Stability, Nonlinear Analysis: Theory, Methods and Applications, vol. 9, no. 10, pp. 1011-1035.

P. S. Krishnaprasad and J. E. Marsden (1987). Hamiltonian Structures and Stability for Rigid Bodies with Flexible Attachments, Archive for Rational Mechanics and Analysis, vol. 98, no. 1, pp. 71-93.

N. Sreenath, Y. G. Oh, P. S. Krishnaprasad and J. E. Marsden (1988). The Dynamics of Coupled Planar Rigid Bodies Part I: Reduction, Equilibria and Stability, Dynamics and Stability of Systems, vol. 3, no. 1 & 2, pp. 25-49.

J. C. Simo, J. E. Marsden and P. S. Krishnaprasad (1988). The Hamiltonian Structure of Nonlinear Elasticity: The Convective Representation of Solids, Rods, and Plates, Archive for Rational Mechanics and Analysis, vol. 104, no. 2, pp. 125-183.

R. Grossman, P. S. Krishnaprasad and J. E. Marsden (1988). The Dynamics of Two Coupled Rigid Bodies, in M. Levi and F. M. A. Salam (Eds.) Dynamical Systems Approaches to Nonlinear Problems in Systems and Circuits, pp. 373-378, SIAM Publications, Philadelphia, 1988.

Y. G. Oh, N. Sreenath, P. S. Krishnaprasad and J. E. Marsden (1989). The Dynamics of Coupled Planar Rigid Bodies Part II: Bifurcations, Periodic Solutions, and Chaos, Journal of Dynamics and Differential Equations, vol. 1, no. 3, pp. 269-298.

P. S. Krishnaprasad (1989). Eulerian Many-Body Problems, in J. E. Marsden, P.S. Krishnaprasad and J.C. Simo (Eds.), Dynamics and Control of Multibody Systems, in series, Contemporary Mathematics, vol. 97, pp. 187-208, American Mathematical Society, Providence, 1989.

L.-S. Wang, P. S. Krishnaprasad, and J. H. Maddocks (1991). Hamiltonian Dynamics of a Rigid Body in a Central Gravitational Field, Celestial Mechanics and Dynamical Astronomy, vol. 50, pp. 349-386.

A. M. Bloch, P. S. Krishnaprasad, J. E. Marsden and G. S. Alvarez (1992). Stabilization of Rigid Body Dynamics by Internal and External Torques, Automatica, vol. 28, no. 4, pp. 745-756.

L.-S. Wang and P. S. Krishnaprasad (1992). Gyroscopic Control and Stabilization, Journal of Nonlinear Science, vol. 2, pp. 367-415.

L.-S. Wang, J. H. Maddocks and P. S. Krishnaprasad (1992). Steady Rigid-Body Motions in a Central Gravitational Field, Journal of Astronautical Sciences, vol. 40, no. 4, October-December, pp. 449-478.

M. Austin, P. S. Krishnaprasad and L.-S. Wang (1993). Almost Poisson Integration of Rigid Body Systems, Journal of Computational Physics, vol. 107, no. 1, pp. 105-117.

R. Yang and P. S. Krishnaprasad (1994). On the Geometry and Dynamics of Floating Four Bar Linkages, Dynamics and Stability of Systems, vol. 9, no. 1, pp. 19-45.

A. M. Bloch, P. S. Krishnaprasad, J. E. Marsden and T. S. Ratiu (1994). Dissipation Induced Instabilities, Annales de L'Institut Henri Poincaré: Analyse Non Lineare, vol. 11, no. 1, pp. 37-90.

R. Yang, P. S. Krishnaprasad and W. P. Dayawansa (1996) Optimal Control of a Rigid Body with Two Oscillators, Fields Institute Communications, vol. 7, pp. 233-260. (also Institute for Systems Research Technical Report TR 93-63)

A. M. Bloch, P. S. Krishnaprasad, J. E. Marsden and T. S. Ratiu (1996). The Euler-Poincaré Equations and Double Bracket Dissipation, Communications in Mathematical Physics, vol. 175, pp. 1-42, also Fields Institute Technical Report, FI94-CT01, and The Erwin Schroedinger International Institute for Mathematical Physics, Vienna, Preprint ESI 73 (1994).

P. S. Krishnaprasad (1994). Optimal Control and Poisson Reduction, published only as Institute for Systems Research Technical Report TR-93-87, 16 pages.

R. Yang, P. S. Krishnaprasad, and W. P. Dayawansa (1993). Chaplygin Dynamics and Lagrangian Reduction, in Chien W-Z., Guo Z-H., Guo Y-Z., (Eds.), Proc. 2nd International Conference on Nonlinear Mechanics-(ICNM II), pp. 745-749, Peking University Press, China.

P. S. Krishnaprasad and C. A. Berenstein (1984). On the Equilibria of Rigid Spacecraft with Rotors, Systems and Control Letters, vol. 4, pp. 157-163.

T. Posbergh, P. S. Krishnaprasad and J. E. Marsden (1987). Stability Analysis of a Rigid Body with a Flexible Attachment using the Energy-Casimir Method, in M. Luksic, C. F. Martin and W. Shadwick (Eds.), Differential Geometry: The Interface between Pure and Applied Mathematics, in series, Contemporary Mathematics Vol. 68, pp. 253-273, American Mathematical Society, Providence.

P. S. Krishnaprasad (1990). Geometric Phases and Optimal Reconfiguration for Multi-body System, Proc. 1990 American Control Conference, pp. 2240-2244, American Automatic Control Council, Philadelphia.

P. S. Krishnaprasad and R. Yang (1991). Geometric Phases, Anholonomy and Optimal Movement, Proc. IEEE International Conference on Robotics and Automation, pp. 2185-2189, IEEE, New York.

P. S. Krishnaprasad, R. Yang and W. P. Dayawansa (1991). Control Problems on Principal Bundles and Nonholonomic Mechanics, Proc. 30th IEEE Conference on Decision and Control, pp. 1133-1138, IEEE, New York.

F. Zhang and P. S. Krishnaprasad (2004). Coordinated Orbit Transfer for Satellite Cluster, in E. Belbruno and P. Gurfil (Eds.) Astrodynamics, Space Missions, and Chaos, in the series, Annals of the New York Academy of Sciences, vol. 1017, pp. 112-137.

[see also Geometric Mechanics subsection above for related material]

The role of temporal and spatial patterns in the synthesis of control signals is the subject of these papers. The methods range from averaging on Lie groups, to stability and bifurcation of solutions of PDE’s of activator-inhibitor type for control of distributed actuator arrays, and spatial wavelet decompositions on sensor arrays. The work on temporal averaging on Lie groups, when specialized to the setting of the Euclidean group in dimensions 2 and 3 yields scripts for motion control of ground robots and underwater robots. The notion of a variable geometry truss underlies a theory for control of snake-like robots. The roller racer is a prime example where kinematic constraints are well-augmented by conservation laws, resulting in dynamically-based motion scripts. Addressing large arrays of actuators (such as in spatial light modulators) poses communicaton problems. Activator-inhibitor equations and associated nonlinear dynamics suggest ways to cope with this by exploiting spatial patterns and their controllability.

N. E. Leonard and P. S. Krishnaprasad (1995). Motion Control of Drift-Free, Left-Invariant Systems on Lie Groups, IEEE Transactions on Automatic Control, vol. 40, no.9, pp. 1539-1554.

N. E. Leonard and P. S. Krishnaprasad (1994). High-Order Averaging on Lie Groups and Control of an Autonomous Underwater Vehicle, Proc. 1994 American Control Conference, pp. 157-162, American Automatic Controls Council, Philadelphia.

D. Tsakiris and P. S. Krishnaprasad (1994). 2-Module Nonholonomic Variable Geometry Truss Assembly: Motion Control, in L. Sciavicco, C. Bonivento, F. Nicolo, (Eds.), Proc. Fourth IFAC Symposium on Robot Control '94, Capri, Italy, September 19-21, pp. 263-268, Pergamon Press, (also Institute for Systems Research Technical Report TR 93-90).

N. E. Leonard and P. S. Krishnaprasad (1994). Control of Switched Electrical Networks Using Averaging on Lie Groups, Proc. 33rd IEEE Conference on Decision and Control, pp. 1919-1924, IEEE, New York.

P. S. Krishnaprasad and D. Tsakiris (1994). G-Snakes: Nonholonomic Kinematic Chains on Lie Groups, Proc. 33rd IEEE Conference on Decision and Control, pp. 2955-2960, IEEE, New York.

N. E. Leonard and P. S. Krishnaprasad (1994). Motion Control of an Autonomous Underwater Vehicle with an Adaptive Feature, Proc. Symposium on Autonomous Underwater Vehicle Technology, pp. 283-288, IEEE Oceanic Engineering Society, Cambridge.

P. S. Krishnaprasad and D. Tsakiris (1995). Oscillations, SE(2)-Snakes and Motion Control, Proc. 34th IEEE Conference on Decision and Control, pp. 2806-2811, IEEE, New York.

E. W. Justh, P. S. Krishnaprasad and F. Kub (1997). Convergence Analysis and Analog Circuit Applications for a Class of Networks of Nonlinear Coupled Oscillators, recommended for publication pending final revision, in IEEE Transactions on Neural Networks, Final version was not submitted.

G. A. Kantor and P. S. Krishnaprasad (2001). An Application of Lie Groups in Distributed Control Networks, Systems and Control Letters, vol. 43, no.1, pp. 43-52.

E. W. Justh and P. S. Krishnaprasad (2001). Pattern-forming Systems for Control of Large Arrays of Actuators, Journal of Nonlinear Science, vol. 11, pp. 239-277.

P. S. Krishnaprasad and D. P. Tsakiris (2001). Oscillations, SE(2)-Snakes and Motion Control: A Study of the Roller Racer, Dynamical Systems, Vol. 16, No. 4, pp. 347-397.

V. Manikonda and P. S. Krishnaprasad (2002). Controllability of a Class of Underactuated Mechanical Systems with Symmetry, Automatica, Vol. 39, pp. 1837-1850.

The global structure of spaces of finite dimensional linear input-output systems is the subject of these papers. Aspects of topology, bundle structure, orbits of group actions, and stratification into lower dimensional cells in these spaces are explored. Specialization to the physically important setting of passive systems is achieved using results from electrical network theory. For the purposes of the identification problem, it is necessary to suggest natural probability densities on spaces of systems that are candidate prior densities for Bayesian methods. To this end riemannian metrics and associated heat equations on spaces of rational functions are examined. The Fisher-Rao metric and metrics induced by quotienting of group actions are examples.

P. S. Krishnaprasad (1977). Geometry of Parametric Models: Some Probabilistic Questions, Proc. 15th Allerton Conference Control, Communication and Computing, Allerton, Illinois, pp. 661-670, (Invited Paper).

P. S. Krishnaprasad (1980). On the Geometry of Linear Passive Systems, in C.I. Byrnes and C.F. Martin (Eds.) Linear Systems Theory, in series Lectures in Applied Mathematics vol. 18, pp. 253-275, American Mathematical Society, Providence, R.I. (Also Notices of the AMS, Nov. 1978, abstracts).

R. W. Brockett and P. S. Krishnaprasad (1980). A Scaling Theory for Linear Systems, IEEE Transactions on Automatic Control, vol. AC-25, no. 2, pp. 197-207.

P. S. Krishnaprasad and C. F. Martin (1983). On Families of Systems and Deformations, International Journal of Control, vol. 38, no. 5, pp. 1055-1079.

P. A. Fuhrmann and P. S. Krishnaprasad (1986). Towards a Cell Decomposition for Rational Functions, IMA Journal of Mathematical Control and Information, (special issue on Parametrization Problems), vol.3, no. 2 & 3, pp. 137-150.

The interaction between structural-symbolic descriptions and design and control of robots is a theme of these papers. Multibody dynamics models generated (by DYNAMAN) from systematic applications of mechanical balance laws are organized symbolically into manageable collections of equations for simulation and design exercises. Differential equation descriptions of mobile robots are integrated with motion scripts in the form of expressions in a context free language (MDLe) constructed from stringing together atomic motions. A departure from earlier work is represented by the introduction of interrupt primitives linked to sensor data. A planner for nonholonomic mobile robots and an implementation of the language MDLe are discussed here. A broad outline of a hierarchical architecture for motion control emerges in these papers. In particular this architecture is compatible with the type of embodiments for mobile robots as discussed in some of the work in the subsection on Oscillations, Patterns and Motion Control.

N. Sreenath and P. S. Krishnaprasad (1989). Multibody Simulation in an Object Oriented Programming Environment, in R. Grossman (Ed.), Symbolic Computation: Applications to Scientific Computing, pp. 153-180, SIAM Publications, Philadelphia.

P. S. Krishnaprasad (1997). Motion Control and Coupled Oscillators, Board of Mathematical Sciences, National Research Council, Motion, Control and Geometry: Proceedings of a Symposium, pp. 52-65, National Academy Press, Washington D.C.

V. Manikonda, P. S. Krishnaprasad and J. Hendler (1995). A Motion Description Language and a Hybrid Architecture for Motion Planning with Nonholonomic Robots, Proc. IEEE International Conference on Robotics and Automation, (Nagoya, Japan), pp. 2021-2028, IEEE, New York.

V. Manikonda, J. Hendler and P. S. Krishnaprasad (1995). Formalizing Behavior-based Planning for Nonholonomic Robots, Proc. 14th International Joint Conference on Artificial Intelligence, pp. 142-149, Morgan Kaufmann, San Mateo.

V. Manikonda, P. S. Krishnaprasad and J. Hendler (1998). Languages, Behaviors, Hybrid Architectures and Motion Control, in J. Baillieul and J. C. Willems (Eds.), Mathematical Control Theory (volume in honor of the 60th birthday of Roger Brockett), pp. 199-226, Springer-Verlag, New York.

D. Hristu-Varsakelis, P.S. Krishnaprasad, S. Andersson, F. Zhang, P. Sodre, L. D'Anna (2000). The MDLe Engine: a Software Tool for Hybrid Motion Control, Institute for Systems Research Technical Report, ISR TR 2000-54, 11 pages, University of Maryland.

D. Hristu-Varsakelis, M. Egerstedt, and P. S. Krishnaprasad (2003). On the Structural Complexity of the Motion Description Language MDLe, Proc. 42nd IEEE Conference on Decision and Control, pp 3360-3365, IEEE, New York.

D. Hristu-Varsakelis, S. Andersson, F. Zhang, P. Sodre, and P. S. Krishnaprasad (2003). A motion description language for hybrid system programming, preprint.

Actuators and mechanisms display non-ideal nonlinear behavior due to backlash in gear trains, friction in bearings, impact during contact, and hysteresis in constitutive relations. Mitigating the influence of such uncertain behavior on the performance of robotic devices and systems through modeling, inversion, and control is the theme of these papers. The exploitation of coupled fields (piezo-electric effect, magnetostriction) in precise "smart" micro-positioning devices also demands similar approaches. The problem of hysteresis is investigated by resorting to microscopic modeling via the Landau-Lifshitz equations, and phenomenological input-output descriptions such as the one associated with Preisach and others in magnetism. Alternative low-dimensional models for ease of use in real-time control applications also are investigated.

N. E. Leonard and P. S. Krishnaprasad (1992). Adaptive Friction Compensation for Bi-Directional Low-Velocity Position Tracking, Proc. 31st IEEE Conference on Decision and Control, pp. 267-273, IEEE, New York.

Q. F. Wei, W. P. Dayawansa and P. S. Krishnaprasad (1993). Modeling of Impact on a Flexible Beam, Proc. 32nd IEEE Conference on Decisioin and Control, pp. 1377-1382, IEEE, New York.

Q. F. Wei, W. P. Dayawansa and P. S. Krishnaprasad (1994). Approximation of Dynamical Effects due to Impact on Flexible Bodies, Proc. 1994 American Control Conference, pp. 1841-1845, American Automatic Controls Council, Philadelphia.

T. K. Shing, L. W. Tsai and P. S. Krishaprasad (1993).An Improved Model for the Dyanmics of Spur Gear Systems with Backlash Consideration, Advances in Design Automation-vol. 1, DE-vol. 65-1, pp. 235-243, ASME, New York.

T. K. Shing, L. W. Tsai and P. S Krishnaprasad (1994). Dyanmic Model of a Spur Gear System with Backlash and Friction Consideration, Proc. 1994 ASME Design Technical Conference, DE-vol. 71, Machine Elements and Machine Dynamics, pp. 155-163, ASME, New York.

R. Venkataraman, W. P. Dayawansa, J. Loncaric and P. S. Krishnaprasad (1995). Smart Motor Concept Based on Piezoelectric-Magnetostrictive Resonance, In I. Chopra (ed.) Proc. SPIE Conference on Smart Structures and Materials 1995: Special Conference on Smart Structures and Integrated Systems, SPIE vol. 2443, pp. 763-770, SPIE Bellingham.

R. Ventakaraman and P. S. Krishnaprasad (2000). A Novel Algorithm for the Inversion of the Preisach operator, in V. V. Varadan (Ed. ) Smart Structures and Materials 2000; Mathematics and Control in Smart Structures, Proc. SPIE, vol. 3984, pp. 404-414.

X. Tan, J. S. Baras and P. S. Krishnaprasad (2000). Fast Evaluation of Demagnetizing Field in Three Dimensional Micromagnetics Using Multipole Approximation, In V. V. Varadan (Ed.) Smart Structures and Materials 2000; Mathematics and Control in Smart Structures, Proc. SPIE, vol. 3984, pp. 195-201.

X. Tan, J. S. Baras and P. S. Krishaprasad (2000). Computational Micromagnetics for Magnetostrictive Actuators, in V. V. Varadan (Ed.) Smart Structures and Materials 2000; Mathematics and Control in Smart Structures, Proc. SPIE, vol. 3984, pp. 162-173.

R. Venkataraman aand P. S. Krishnaprasad (2000). Approximate Inversion of Hysteresis: Theory and Numberical Results, Proc. 39th IEEE Conference on Decision and Control, pp. 4448-4454, IEEE, New York.

X. Tan, R. Venkataramn and P. S. Krishnaprasad (2001). Control of Hysteresis: Theory and Experimental results, Smart Structures and Materials 2001, Modeling, Signal Processing, and Control in Smart Structures, Proceedings of SPIE 2001, vol. 4326, pp. 101-112.

P. S. Krishnaprasad and X. Tan (2001). Cayley Transforms in Micromagnetics, Physica B, vol. 306, pp. 195-199.

X. Tan, J. S. Baras and P. S. Krishaprasad (2003). A Dynamic Model of Magnetostrictive Hysteresis, Proc. American Control Conference, pp. 1074-1079, American Automatic Control Council, Philadelphia.

R. V. Iyer, X. Tan and P. S. Krishnaprasad (2005). Aproximate Inversion of Hysteresis with Application to Control of Smart Actuators, IEEE Transactions on Automatic Control, vol. 50, no. 6, pp. 798-810.

X. Tan, J. S. Baras and P. S. Krishnaprasad (2005). Control of Hysteresis in Smart Actuators with Applications to Micro-positioning, Systems and Control Letters, vol. 54, ho. 5, pp. 483-492.

R. V. Iyer and P. S> Krishnaprasad (2005). On a Low-Dimensional Model for Ferromagnetism, Nonlinear Analysis: Theory, Methods and Applications, vol. 61, no. 8, pp. 1447-1482.

The subject of nonlinear filtering is a basis for a variety of estimation problems including system identification, as discussed in some of these papers. The associated estimation algebra is a subalgebra of a current algebra. Modern approaches to the nonlinear filtering problem exploit computational advances by stochastic simulation leading to a family of particle filters. In contrast to model-based methods for filtering, signal processing applications such as blind separation of mixtures of signals demand methods such as ICA derived from a statistical-geometric framework. Advances in wavelet theory and frames stimulated our contributions to approximation of static maps and transfer functions. The orthogonal matching pursuit (OMP) algorithm is an efficient tool for constructing approximations. A variety of technologies, including tactile sensing and acoustic guidance in robotics, and adaptive optics for correcting wavefronts distorted by propagation media, influenced novel solutions to inverse problems presented in some of these papers.

D. Rohler and P. S. Krishnaprasad (1981). Radon Inversion and Kalman Reconstructions: A Comparison, IEEE Transactions on Automatic Control, vol. AC-26, no. 2, pp. 483-487.

P. S. Krishnaprasad and S. I. Marcus (1981). Some Nonlinear Filtering Problems Arising in Recursive Identification , in M. Hazewinkel and J.C. Willems (Eds.), Stochastic Systems: The Mathematics of Filtering, Identification and Applications, pp. 299-304, Reidel, Dordrecht.

P. S. Krishnaprasad and S. I, Marcus (1982). On the Lie Algebra of the Identification Problem, Proc. IFAC Symposium on. Digital Control, New Delhi, India.

P. S. Krishnaprasad, S. I. Marcus and M. Hazewinkel (1981). System Identification and Nonlinear Filtering: Lie Algebras, Proc. 20th IEEE Conference on Decision and Control, pp. 330-334, IEEE, New York.

J. S. Baras and P. S. Krishnaprasad (1982). Asymptotic Observers as Limits of Nonlinear Filters, Proc. 21st IEEE Conference on Decision and Control, pp. 1126-1127, IEEE, New York.

P. S. Krishnaprasad, S. I. Marcus and M. Hazewinkel (1983). Current Algebras and the Identification Problem, Stochastics, vol. 11, pp. 65-101.

C. A. Berenstein, P. S. Krishnaprasad and B. A. Taylor (1985). Deconvolution Methods for Multisensors, Technical Report, Department of Mathematics, University of Maryland, MD85-23-CB, TR85-19, June 1985, 63 pages (Also available from Defense Technical Information Center, Washington D.C.)

Y. C. Pati and P. S. Krishnaprasad (1991). Discrete Affine Wavelet Transforms for Analysis and Synthesis of Feed-forward Neural Networks, in R.P. Lippmann, J.E. Moody, D.S. Touretzky (Eds.), Advances in Neural Information Processing Systems III, pp. 743-749, Morgan Kaufmann Publishers, San Mateo, 1991.

Y. C. Pati and P. S. Krishnaprasad (1992). Decomposition of H2(pi+) via Rational Wavelets, Proc. Conference on Information Sciences and Systems, pp. 15-20, Princeton University.

Y. C. Pati and P. S. Krishnaprasad (1992). Approximations of Stable Linear Systems via Rational Wavelets, Proc. 31st IEEE Conference on Decision and Control, pp. 1502-1507, IEEE, New York.

Y. C. Pati, P. S. Krishnaprasad and M. C. Peckerar (1992). An Analog Neural Network Solution to the Inverse Problems of ‘Early Taction’, IEEE Transactions on Robotics and Automation, vol. 8, no. 2, pp. 196-212.

Y. C. Pati and P. S. Krishnaprasad (1993). Analysis and Synthesis of Feed-forward Neural Networks Using Discrete Affine Wavelet Transformations, IEEE Transactions on Neural Networks, vol. 4, no. 1, pp. 73-85

R. Rezaiifar, Y. C. Pati, P. S. Krishnaprasad and W. P. Dayawansa (1993). Wavelet Based Identification of Smart Structures with Surface Mounted Actuators and Sensors, Proc. 32nd IEEE Conference on Decision and Control, pp. 486-491, IEEE, New York.

Y. C. Pati, R. Rezaiifar and P. S. Krishnaprasad (1993). Orthogonal Matching Pursuit: Recursive Function Approximation with Applications to Wavelet Decomposition, Proc. 27th Asilomar Conference on Signals, Systems and Computers, pp 40-44.

Y. C. Pati, R. Rezaiifar, P. S. Krishnaprasad and W. P. Dayawansa (1993). A Fast Recursive Algorithm for System Identification and Model Reduction using Rational Wavelets, Proc. 27th Asilomar Conference on Signals, Systems and Computers, pp 35-39.

Y. C. Pati and P. S. Krishnaprasad (1994). Rational Wavelets in Model Reduction and System Identification, Proc. 33rd IEEE Conference on Decision and Control, pp. 3394-3399, IEEE, New York.

A. J. Newman and P. S. Krishnaprasad (2000). Computing Balanced Realizations for Nonlinear Systems, in M. Fliess and A. Eljai (Eds.) Proc. 14th International Symposium on Mathematical Theory of Networks and Systems (CDROM), 10 pages.

E. W. Justh, M. A. Vorontsov, G. W. Carhart and L. A. Beresnev and P. S. Krishnaprasad (2000). Adaptive Wavefront Control Using a Nonlinear Zernike Filter, in High-resolution Wavefront Control: Methods, Devices and Applications II, Proc. 45th Annual Meeting of SPIE, pp. 189-200.

Y. Qi, P. S. Krishnaprasad and S. Shamma (2000). Sub-band Based Independent Component Analysis, Proc. ICA2000, pp. 199-204.

E. W. Justh, P. S. Krishnaprasad and M. A. Vorontsov (2000). Nonlinear Analysis of a High-resolution Optical Wave-front Control System, Proc. 39th IEEE Conference on Decision and Control, pp. 3301-3306, IEEE, New York.

E. W. Justh, M. A. Vorontsov, G. W. Carhart, L. A. Beresnev and P. S. Krishnaprasad (2001). Adaptive Optics with Advanced Phase-Contrast Techniques: Part II High Resolution Wave-Front Control, Journal of the Optical Society of America A, vol. 18, no. 6, pp. 1300-1311.

A. A. Handzel and P. S. Krishnaprasad (2002). Bio-mimetic Sound Source Localization, IEEE Sensors Journal, vol. 2, no. 6, pp. 607-616.

S. Andersson and P. S. Krishnaprasad (2002). Degenerate Gradient Flows: A Comparison Study of Convergence Rate Estimates, Proc. 41st IEEE Conference on Decision and Control, pp. 4712-4717, IEEE, New York.

E. W. Justh, P. S. Krishnaprasad and M. A. Vorontsov (2004). Analysis of a High-Resolution Optical Wave-Front Control System, Automatica, vol. 40, no. 7, pp. 1129-1141.

B. Azimi-Sadjadi and P. S. Krishnaprasad (2004). A Particle Filtering Approach to Change Detection for Nonlinear Systems , EURASIP Journal on Applied Signal Processing, vol. 15, pp. 2295-2305.

B. Azimi-Sadjadi and P. S. Krishnaprasad (2005). Approximate Nonlinear Filtering and its Applications in Navigation Automatica, vol. 41, no. 6, pp. 945-956

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