34 research outputs found
Exploratory simulation of an Intelligent Iris Verifier Distributed System
This paper discusses some topics related to the latest trends in the field of
evolutionary approaches to iris recognition. It presents the results of an
exploratory experimental simulation whose goal was to analyze the possibility
of establishing an Interchange Protocol for Digital Identities evolved in
different geographic locations interconnected through and into an Intelligent
Iris Verifier Distributed System (IIVDS) based on multi-enrollment. Finding a
logically consistent model for the Interchange Protocol is the key factor in
designing the future large-scale iris biometric networks. Therefore, the
logical model of such a protocol is also investigated here. All tests are made
on Bath Iris Database and prove that outstanding power of discrimination
between the intra- and the inter-class comparisons can be achieved by an IIVDS,
even when practicing 52.759.182 inter-class and 10.991.943 intra-class
comparisons. Still, the test results confirm that inconsistent enrollment can
change the logic of recognition from a fuzzified 2-valent consistent logic of
biometric certitudes to a fuzzified 3-valent inconsistent possibilistic logic
of biometric beliefs justified through experimentally determined probabilities,
or to a fuzzified 8-valent logic which is almost consistent as a biometric
theory - this quality being counterbalanced by an absolutely reasonable loss in
the user comfort level.Comment: 4 pages, 2 figures, latest version: http://fmi.spiruharet.ro/bodorin
A New Approach to Nonlinear Tracking Control Based on Fuzzy Approximation
The problem of tracking control is addressed for a class of nonlinear systems with uncertainties. The original nonlinear systems are approximated by a fuzzy T-S model based on which a state-feedback controller is constructed by using the linear matrix inequalities. The approximating error is eliminated by an adaptive compensator based on fuzzy logic systems. The effectiveness of the proposed control scheme is demonstrated by a simulation example. The main advantage is that the designer makes milder constraint assumption for the approximation error and the uncertainties in nonlinear systems
Uncertain Fractional Order Chaotic Systems Tracking Design via Adaptive Hybrid Fuzzy Sliding Mode Control
In this paper, in order to achieve tracking performance of uncertain fractional order chaotic systems an adaptive hybrid fuzzy controller is proposed. During the design procedure, a hybrid learning algorithm combining sliding mode control and Lyapunov stability criterion is adopted to tune the free parameters on line by output feedback control law and adaptive law. A weighting factor, which can be adjusted by the trade-off between plant knowledge and control knowledge, is adopted to sum together the control efforts from indirect adaptive fuzzy controller and direct adaptive fuzzy controller. To confirm effectiveness of the proposed control scheme, the fractional order chaotic response system is fully illustrated to track the trajectory generated from the fractional order chaotic drive system. The numerical results show that tracking error and control effort can be made smaller and the proposed hybrid intelligent control structure is more flexible during the design process
Identification of the De-synchronization, Synchronization and Forced Oscillation Phenomenon of a Nonlinear System
Abstract-The phenomena of de-synchronization, synchronization, and forced oscillation has been investigation using describing function theory for a two input and two output nonlinear system containing saturation-type nonlinearities and subjected to high-frequency deterministic signal for the purpose of limit cycle quenching. The analytical results have been compared with the results of digital simulation Matlab-Simulink for a typical example varying the nonlinear element