Narrow Results

Structural and parametric identification of nonlinear continuous dynamic systems with a closed cycle on a set of continuous block-oriented models with feedback is considered. The method of structural identification in the steady state based on the observation of the system's input and output variables at the input periodic influences is proposed. The solution of the parameter identification problems, which can be immediately connected with the structural identification problem, is carried out in the steady and transient states by the method of least squares. The structural and parametric identification algorithms are investigated by means of both theoretical analysis and computer modeling.

The paper analyzes some of Tesla's works and his most remarkable views concerning the problem of formulating theoretical bases of automatic control. As a tribute to Tesla's work on remote control of automated systems, as well to his (at the time) far-seeing visions, special attention is paid to solving the complex problem of control and feedback application. A more detailed discussion of the way and origin of formulating theoretical bases of automatic control is given. Besides, in more detail are presented the related pioneering works of Professor Nicholas Bernstein, great Russian physiologist who formulated the basic rules of the self-regulating movements of man. Bernstein has achievements of highest scientific significance that has been in a direct function of identifying and proving the priority of his pioneering contributions in the domain of feedback, i.e. control and principles of cybernetics.

The article presents the facts about the pioneering research results of Professor Nikolai Bernstein in the area of man's voluntary movements. Relevant data are given concerning the priority of introducing the notion of feedback in the process of active voluntary human movements, twelve years before the known Wiener's publication. Bernstein demonstrated how the problems of general physiology can be explored in terms of the structural analysis of movements. He dealt with the most important aspects of the vital activity of higher organisms, and how this has been accorded the place in physiology and, when it developed, promised to be of the greatest value in cybernetics and in the exact mathematical formulation of a physiological theory of motor behavior. In his research, Bernstein modeled the function of the central nervous system and offered the cyberneticists a system for the development of analogs for experimental model-making that was not only incomparably richer than examples of internal stabilizing processes (blood-pressure, temperature and sugar-level regulating systems, for example), and also more complex than the systems of dynamic regulation that have already been studied in some depth, such as the mechanisms of ocular accommodation, or of the pupillary reaction.

In this paper, a user-centered framework is proposed for video database modeling and retrieval to provide appealing multimedia experiences on the content-based video queries. By incorporating the Hierarchical Markov Model Mediator (HMMM) mechanism, the source videos, segmented video shots, visual/audio features, semantic events, and high-level user perceptions are seamlessly integrated in a video database. With the hierarchical and stochastic design for video databases and semantic concept modeling, the proposed framework supports the retrieval for not only single events but also temporal sequences with multiple events. Additionally, an innovative method is proposed to capture the individual user's preferences by considering both the low-level features and the semantic concepts. The retrieval and ranking of video events and the temporal patterns can be updated dynamically online to satisfy individual user's interest and information requirements. Moreover, the users' feedbacks are efficiently accumulated for the offline system training process such that the overall retrieval performance can be enhanced periodically and continuously. For the evaluation of the proposed approach, a soccer video retrieval system is developed, presented, and tested to demonstrate the overall retrieval performance improvement achieved by modeling and capturing the user preferences.

This chapter undertakes an in-depth analysis of the interaction between OCR and information retrieval. In particular, after providing an introduction to information retrieval, we report on retrieval effectiveness from OCR generated document collections. It will be shown that, in general, average precision and recall is not affected while document term assignment, weighting and document ranking may be affected. We also point out that even though OCR errors do not affect average retrieval effectiveness, there are other consequences that should be considered when OCR text is applied.