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Use of explicit integration methods for power electronic circuits with ideal switch models significantly improves simulation speed. The PLECS package [1] has effectively used this idea; however, the implementation details involved in PLECS are not available in the public domain. Recently, a basic framework, called the ``ELEX" scheme, for implementing explicit methods has been described [2]. A few modifications of the ELEX scheme for efficient handling of inductors and switches have been presented in [3]. In this paper, the approach presented in [3] is further augmented with robust schemes that enable systematic equation formulation for circuits involving switches, inductors, and transformers. Several examples are presented to illustrate the proposed schemes., Comment: 16 pages, 35 figures

Some aspects of the ELectrical EXplicit (ELEX) scheme for using explicit integration schemes in circuit simulation are discussed. It is pointed out that the parallel resistor approach, presented earlier to address singular matrix issues arising in the ELEX scheme, is not adequately robust for incorporation in a general-purpose simulator for power electronic circuits. New topology-aware approaches, which are more robust and efficient compared to the parallel resistor approach, are presented. Several circuit examples are considered to illustrate the new approaches., Comment: 8 pages, 9 figures

Use of explicit methods for simulating electrical circuits, especially for power electronics applications, is described. Application of the forward Euler method to a half-wave rectifier is discussed, and the limitations of a fixed-step method are pointed out. Implementation of the Runge-Kutta-Fehlberg (RKF) method, which allows variable time steps, for the half-wave rectifier circuit is discussed, and its advantages pointed out. Formulation of circuit equations for the purpose of simulation using the RKF method is described for some more examples. Stability and accuracy issues related to power electronic circuits are brought out, and mechanisms to address them are presented. Future plans related to this work are described., Comment: 13 pages, 22 figures

Extension of the open-source simulation package GSEIM for power electronics applications is presented. Recent developments in GSEIM, including those oriented specifically towards power electronic circuits, are described. Some examples of electrical element templates, which form a part of the GSEIM library, are discussed. Representative simulation examples in power electronics are presented to bring out important features of the simulator. Advantages of GSEIM for educational purposes are discussed. Finally, plans regarding future developments in GSEIM are presented., Comment: 8 pages, 11 figures

A new simulation package, GSEIM, for solving a set of ordinary differential equations is presented. The organisation of the program is illustrated with the help of a block diagram. Various features of GSEIM are discussed. Two ways of incorporating new elements in GSEIM, viz., as a template and as a subcircuit, are explained by taking a specific example. Simulation examples are described to bring out the capabilities of GSEIM., Comment: 14 pages, 25 figures

Syllable detection is an important speech analysis task with applications in speech rate estimation, word segmentation, and automatic prosody detection. Based on the well understood acoustic correlates of speech articulation, it has been realized by local peak picking on a frequency-weighted energy contour that represents vowel sonority. While several of the analysis parameters are set based on known speech signal properties, the selection of the frequency-weighting coefficients and peak-picking threshold typically involves heuristics, raising the possibility of data-based optimisation. In this work, we consider the optimization of the parameters based on the direct minimization of naturally arising task-specific objective functions. The resulting non-convex cost function is minimized using a population-based search algorithm to achieve a performance that exceeds previously published performance results on the same corpus using a relatively low amount of labeled data. Further, the optimisation of system parameters on a different corpus is shown to result in an explainable change in the optimal values., Comment: 6 pages, 3 figures, accepted in National Conference on Communications (NCC) 2020

Multi-objective optimisation of damper placement in dynamically symmetric adjacent buildings is considered with identical viscoelastic dampers used for vibration control. First, exhaustive search is used to describe the solution space in terms of various quantities of interest such as maximum top floor displacement, maximum floor acceleration, base shear, and interstorey drift. With the help of examples, it is pointed out that the Pareto fronts in these problems contain a very small number of solutions. The effectiveness of two commonly used multi-objective evolutionary algorithms, viz., NSGA-II and MOPSO, is evaluated for a specific example., Comment: 11 pages, 8 figures, 4 tables

Hybridisation of the multi-objective optimisation algorithm NSGA-II and local search is proposed for water distribution system design. Results obtained with the proposed algorithm are presented for four medium-size water networks taken from the literature. Local search is found to be beneficial for one of the networks in terms of finding new solutions not reported earlier. It is also shown that simply using an external archive to save all non-dominated solutions visited by the population, even without local search, leads to substantial improvement in the non-dominated set produced by the algorithm., Comment: 5 pages, 1 figure

This article is withdrawn because the co-authors are not in favor of publication., Comment: This article was uploaded by mistake without taking consent of co-authors including my Ph.D. guide. The co-authors are not in favor of publication of this article in arXiv. Hence I am withdrawing it. This is my mistake and I apologize for this

Application of the multi-objective particle swarm optimisation (MOPSO) algorithm to design of water distribution systems is described. An earlier MOPSO algorithm is augmented with (a) local search, (b) a modified strategy for assigning the leader, and (c) a modified mutation scheme. For one of the benchmark problems described in the literature, the effect of each of the above features on the algorithm performance is demonstrated. The augmented MOPSO algorithm (called MOPSO+) is applied to five benchmark problems, and in each case, it finds non-dominated solutions not reported earlier. In addition, for the purpose of comparing Pareto fronts (sets of non-dominated solutions) obtained by different algorithms, a new criterion is suggested, and its usefulness is pointed out with an example. Finally, some suggestions regarding future research directions are made., Comment: 16 pages, 12 figures

It is shown that the use of an external archive, purely for storage purposes, can bring substantial benefits in multi-objective optimization. A new scheme for archive management for the above purpose is described. The new scheme is combined with the NSGA-II algorithm for solving two multi-objective optimization problems, and it is demonstrated that this combination gives significantly improved sets of Pareto-optimal solutions. The additional computational effort because of the external archive is found to be insignificant when the objective functions are expensive to evaluate., Comment: 9 pages, 8 figures, submitted to IEEE Transactions on Evolutionary Computation