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The present paper discusses an important issue of identification and control of a nonlinear dynamical system using neural network. A novel method based on neural network model has been developed here which makes the task of calculating the system parameters simple in comparison to the methods reported so far for the extraction of system dynamics of a nonlinear system. The updated parameters of the system are obtained using a learning algorithm and the controller is tuned accordingly. Further the system stability is compared with that obtained by existing networks and the simulated results show that our method is superior.

In this paper a study on the references is performed. An algorithm has been developed to find the referent of implicit anaphora. A representation of noun storage in knowledgebase is devised. The algorithm is designed to identify the presence of implicit anaphora, and is implemented in C++. A prototype lexicon has been designed. The algorithm worked well for test inputs. The results are presented.

This paper carries forward Sherman and Ostrach's (J. Fluid Mech. 24 (1966) 661–671) analysis for the magnetohydrodynamic thermal stability problem in completely confined fluids and derives a bound for the linear complex growth rate of an arbitrary oscillatory perturbation which may be neutral or unstable through the use of some nontrivial integral estimates obtained from the coupled system of perturbation equations governing the problem.

This paper presents the assessment and comparison of power quality problems created by common electronic loads. T1he key issues covered are reactive kVA drawn, harmonic spectrum, total harmonic distortion, power factor and displacement factor. The different loads considered in this study are commonly used electronic gadgets as personal computer, printer and fluorescent tube. The results highlight the extent of damage being caused by these loads in polluting the utility grid. Improvement in quality of power attained by the use of constant voltage transformer is also presented. Use of active filters for Improvement of power factor of such electronic loads is suggested.

The transient behaviour of a three phase induction motor in the braking mode is investigated when the motor is fed from a variable frequency source. Appropriate voltage and frequency conditions to ensure minimum stopping time for plugging as well as for the case when plugging is used in conjunction with regenerative braking are identified. A dynamic model has been developed using the theory of instantaneous symmetrical component and associated operational equivalent circut and therefrom the transient performance of the motor in both the cases are compared with that of the normal plugging.

The transient behaviour of a three phase induction motor in the braking mode is investigated when the motor is fed from a variable frequency source. Appropriate voltage and frequency conditions to ensure minimum stopping time for plugging as well as for the case when plugging is used in conjunction with regenerative braking are identified. A dynamic model has been developed using the theory of instantaneous symmetrical component and associated operational equivalent circut and therefrom the transient performance of the motor in both the cases are compared with that of the normal plugging.

The transient behaviour of a three-phase induction motor is studied when two diodes are inserted in two of the stator phases of the motor during plugging. The dynamic models are developed using the theory of Instantaneous symmetrical components and its associated operational equivalent circuit. The inline switching constraints are incorporated in the digital simulation of different operating nodes as enforced by diodes. Typical simulated transient patterns are presented for a given system and are compared with corresponding experimental ones.

The phylogenetic relationship between two Drosophila species of the takahashii subgroup, D. takahashii and D. pseudotakahashii, was determined through the study of male genitalia, metaphase and salivary chromosomes, mating behaviour and interspecific hybridization. From all lines of evidence it is concluded that the species are very closely related, and now constitute a pair of allopatric sibling species.

A sufficient condition for the validity of the principle of exchange of stabilities in the Rayleigh-Bénard convection problem under the simultaneous action of a uniform vertical rotation and magnetic field is derived. Furthermore the complex growth rate of an arbitrary oscillatory perturbation, neutral or unstable, is shown to lie inside a semicircle in the right half of the complexp-plane. These results are uniformly valid for all combinations of free insulating, rigid perfectly conducting and rigid insulating boundaries.