Chimera states in coupled sine-circle map lattices

Systems of coupled oscillators have been seen to exhibit chimera states, i.e. states where the system splits into two groups where one group is phase locked and the other is phase randomized. In this work, we report the existence of chimera states in a system of two interacting populations of sine circle maps. This system also exhibits the clustered chimera behavior seen earlier in delay coupled systems. Rich spatio-temporal behavior is seen in different regimes of the phase diagram.We carry out a detailed analysis of the stability regimes and map out the phase diagram using numerical and analytic techniques.Comment: 10 pages, 5 picture

Dynamics of coupled Josephson junctions under the influence of applied fields

We investigate the effect of the phase difference of applied fields on the dynamics of mutually coupled Josephson junction. The system desynchronizes for any value of applied phase difference and the dynamics even changes from chaotic to periodic motion for some values of applied phase difference. We report that by keeping the value of phase difference as $\pi$, the system continues to be in periodic motion for a wide range of system parameter values which might be of great practical applications.Comment: 13 pages 13 figure

Phase effects on synchronization by dynamical relaying in delay-coupled systems

Synchronization in an array of mutually coupled systems with a finite time-delay in coupling is studied using Josephson junction as a model system. The sum of the transverse Lyapunov exponents is evaluated as a function of the parameters by linearizing the equation about the synchronization manifold. The dependence of synchronization on damping parameter, coupling constant and time-delay is studied numerically. The change in the dynamics of the system due to time-delay and phase difference between the applied fields is studied. The case where a small frequency detuning between the applied fields is also discussed.Comment: 14 pages, 8 figures, Accepted for publication in "CHAOS

Efficacy of Topical Eberconazole in the Treatment of Tinea Cruris and Tinea Corporis

Expert opinio

A comparison study of the clinical efficacy and safety of topical adapalene gel (0.1%) and tretinoin cream (0.025%) in the treatment of acne vulgaris

Background: Adapalene a synthetic retinoid analogue, is an addition to the arsenal of topical retinoids developed for the topical treatment of acne vulgaris. The study was designed to compare the clinical efficacy and safety of topical adapalene gel 0.1% and tretinoin cream 0.025% in the treatment of acne vulgaris.Methods: A total of 80 patients with grade I-III acne vulgaris seen in the out-patient department of a tertiary care center were randomized to 8 weeks of daily treatment with either adapalene gel 0.1% or tretinoin gel 0.025%. Counts of total lesions, inflammatory lesions and non-inflammatory lesions were made at baseline and again at treatment weeks 2, 4, 6 and 8. Global assessment ratings, based on percent lesion reduction from baseline were also made. Side-effects like erythema, burning, pruritus, scaling and dryness were rated on a 0-3 severity scale.Results: Out of 80 patients there were 8 dropouts in the study; the 72 patients who completed the study were evaluated for efficacy and safety. Both adapalene and tretinoin produce dramatic reductions in total, inflammatory and non-inflammatory lesion counts, on an average. Cutaneous side-effects were limited to a mild retinoid dermatitis occurring in both treatment groups however patients treated with adapalene gel tolerated this therapy significantly better than those treated with tretinoin cream.Conclusions: Adapalene gel 0.1% offers comparable efficacy to tretinoin cream 0.025 % cream, but is less irritating. Adapalene gel 0.1% is a safe and effective topical agent in the treatment of mild to moderate acne vulgaris in Indian patients

Evaluation of a puzzle-based virtual platform for improving spatial visualization skills in engineering freshmen

Being able to spatially visualize and mentally rotate is a key skill necessary to succeed in graphics and subsequent engineering courses. Recent research has focused on methods to develop Spatial Visualization (SV) skills in engineering students, as it is a key skill to succeed in most of the STEM fields. However, in most of the engineering schools, the instructors find it very difficult to develop keen SV skills in students. The major factors contributing to this challenge include, but not limited to the huge class sizes, limited time to teach the material, lack of effective demonstrations and the unavailability of feasible hands-on activities. With the funding from the National Science Foundation, the authors are developing a puzzle-based active learning platform called Student Assistant for Visualization in Engineering (SAVE) for developing SV skills in engineering freshman. In the preliminary version of this learning platform, the students are asked to complete a quiz with tasks requiring SV skills. For any incorrect answer, they are provided with automated hints about their mistakes. These hints are expected to help them in solving the following tasks. If they commit three mistakes, the quiz locks itself and creates a report on their performance thus far. The students are able to go back and restart the quiz. The student\u27s target is to complete the quiz with a minimum number of attempts. In the study reported here, the effectiveness of this game platform in conveying essential concepts of engineering graphics is investigated. Firstly, SAVE is implemented in a smaller classroom and the student feedback is collected. Then, it is implemented in a freshmen graphics class in a large public university in the west coast. The performance of the participating students in a follow-up exam is compared against that of a control group. The results show that the use of SAVE improves students\u27 conceptual understanding compared to a control group, as measured by the scores in the follow-up exam

Large-scale unit commitment under uncertainty: an updated literature survey

The Unit Commitment problem in energy management aims at finding the optimal production schedule of a set of generation units, while meeting various system-wide constraints. It has always been a large-scale, non-convex, difficult problem, especially in view of the fact that, due to operational requirements, it has to be solved in an unreasonably small time for its size. Recently, growing renewable energy shares have strongly increased the level of uncertainty in the system, making the (ideal) Unit Commitment model a large-scale, non-convex and uncertain (stochastic, robust, chance-constrained) program. We provide a survey of the literature on methods for the Uncertain Unit Commitment problem, in all its variants. We start with a review of the main contributions on solution methods for the deterministic versions of the problem, focussing on those based on mathematical programming techniques that are more relevant for the uncertain versions of the problem. We then present and categorize the approaches to the latter, while providing entry points to the relevant literature on optimization under uncertainty. This is an updated version of the paper "Large-scale Unit Commitment under uncertainty: a literature survey" that appeared in 4OR 13(2), 115--171 (2015); this version has over 170 more citations, most of which appeared in the last three years, proving how fast the literature on uncertain Unit Commitment evolves, and therefore the interest in this subject