Report (M.S.)--Virginia Polytechnic Institute and State University. M.S. 1992. / Abstract. Includes bibliographical references (leaves 94-97). Also available via the Internet.

In this thesis, three model-based methods are presented for finding the location of a point source with possibly time-varying strength for a class of distributed parameter systems. The first method involves off-line numerical computation of the time-response data at the sensor(s) from all possible source locations and functions of source strength, and comparison of these data with actual measurements. The second method involves approximation of the infinite-dimensional distributed parameter system by a finite-dimensional lumped parameter system: the partial differential and/or integral equations describing the distributed parameter system are replaced by a set of ordinary differential equations, which are obtained through finite difference or finite element methods. The resulting model is used to construct an auto-regressive (AR) filter that takes the sensor data as inputs and produces a scalar output whose value determines the source location. The third method involves off -line steady-state solution of an adjoint problem based on the dual system model. The solutions are used to construct localization functions whose contours, corresponding to a set of sensor data, provide an estimate of the source location. For each method, the sensor data evaluation algorithm is presented, and analysis is given of appropriate sensor placement and the minimal required number of sensors. The robustness of each method to sensor noise and modeling inaccuracies is studied, and techniques to improve robustness are discussed. These techniques include strategic sensor placement to reduce sensitivity to noise and modeling inaccuracies, and prioritization of sensor data in the data evaluation algorithms. In all three methods, a minimal amount of on-line computation is required. The methods are applied to the two-dimensional heat conduction problem with Robin's boundary conditions, and their performances are tested via computer simulations. The thesis concludes with a discussion of the relative strengths and shortcomings of each method and suggestions for future research. / Graduation date: 1999

Not available / text

Not available / text

Thesis (Ph. D.)--University of Texas at Austin, 2002. / Vita. Includes bibliographical references. Available also from UMI Company.

Thesis (Ph. D.)--University of Texas at Austin, 2001. / Vita. Includes bibliographical references. Available also in a digital version from UMI/Dissertation Abstracts International.

Thesis (Ph.D.)--City University of Hong Kong, 2009. / "Submitted to Department of Manufacturing Engineering and Engineering Management in partial fulfillment of the requirements for the degree of Doctor of Philosophy." Includes bibliographical references (leaves 167-187)

Thesis (Ph.D.) - University of Glasgow, 2008. / Ph.D. thesis submitted to the Faculty of Information and Mathematical Sciences, University of Glasgow, 2008. Includes bibliographical references. Print version also available.

Two methods, one for the identification and one for the control implementation of distributed-parameter systems are presented. The methods are designed to identify and control the actual distributed system, without resorting to discretization. They are implemented using discrete sensors and actuators. The identification process is carried out in two steps. First, the eigensolution of the distributed system is identified. The lowest frequencies and associated eigenfunctions are identified using an extension of a time-domain approach developed for discrete systems. The extension to distributed systems is carried out in this dissertation. To this end, the sensors output is interpolated to identify the eigenfunctions. Next, the parameters contained in the equations of motion are identified. The motion of distributed-parameter systems is described in terms of partial differential equations, so that these parameters are in general continuous functions of the spatial variables. For vibrating systems, these parameters ordinarily represent the mass, stiffness and damping distributions. These distributions are expanded in terms of finite series of known functions of the spatial variables multiplied by undetermined coefficients. Then, using the identified eigensolution and assuming that the general nature of the equation of motion is known, use is made of the least squares method, in conjunction with the eigenfunctions orthogonality to compute the undetermined coefficients, thus identifying the actual distributed system. The control system design is based on the concept of independent modal-space control. Implementation of the independent modal-space control method requires that the number of actuators be equal to the number of controlled modes. Because the actuators are discrete elements, control spillover into the uncontrolled modes is experienced. The effect of control spillover is to pump part of the energy imparted to the distributed system into the uncontrolled modes. It is shown that when the independent modal-space control method is used, the energy required to control the controlled modes does not depend on the actuators locations, so that the placement of the actuators does not represent a serious problem, as it can for coupled controls. A new concept in extracting modal coordinates from the system output, namely modal filters, is introduced. Modal filters extract the modal quantities from the sensors data by interpolating the output of the sensors to obtain continuous displacement patterns and by performing certain weighted integrations over the distributed domain. If the interpolation functions are chosen following the same guidelines as in the finite element method, the integrations can be carried out as offline computations, which facilitates the control implementation. It is shown that when modal filters are used, control of the actual distributed system is possible and no spatial discretization is necessary. In addition, observation spillover, a possible significant problem when observers are used, is eliminated. Two numerical examples are presented to illustrate the identification and control methods. The methods described in this dissertation are in terms of vibrating systems, with special emphasis on large flexible structures. However, these methods are applicable to any distributed-parameter system. / Ph. D.

Advances in technology have led to fully integrated operator consoles which offer a broad range of solutions. Industry's move towards networking has resulted in the operator consoles being located at critical sites throughout the plant-floor. However, a lot of programming effort is required in order to use these consoles effectively. <p>The project addressed the problem by developing a software interface for the future user in a distributed automation environment. The system developed is capable of operating on IBM industrial computers, connected through a communications network on a DAE environment. By using the functions provided, the future user is insulated from the lower level control sequences of the operator interface and need only be concerned about the operation of these functions. <p>A description of the development of each phase project is given, and the purpose and operation subroutines are also presented in this report. / Master of Science