Existence of anticipatory, complete and lag synchronizations in time-delay systems

Existence of different kinds of synchronizations, namely anticipatory, complete and lag type synchronizations (both exact and approximate), are shown to be possible in time-delay coupled piecewise linear systems. We deduce stability condition for synchronization of such unidirectionally coupled systems following Krasovskii-Lyapunov theory. Transition from anticipatory to lag synchronization via complete synchronization as a function of coupling delay is discussed. The existence of exact synchronization is preceded by a region of approximate synchronization from desynchronized state as a function of a system parameter, whose value determines the stability condition for synchronization. The results are corroborated by the nature of similarity functions. A new type of oscillating synchronization that oscillates between anticipatory, complete and lag synchronization, is identified as a consequence of delay time modulation with suitable stability condition.Comment: 5 Figures 9 page

Delay time modulation induced oscillating synchronization and intermittent anticipatory/lag and complete synchronizations in time-delay nonlinear dynamical systems

Existence of a new type of oscillating synchronization that oscillates between three different types of synchronizations (anticipatory, complete and lag synchronizations) is identified in unidirectionally coupled nonlinear time-delay systems having two different time-delays, that is feedback delay with a periodic delay time modulation and a constant coupling delay. Intermittent anticipatory, intermittent lag and complete synchronizations are shown to exist in the same system with identical delay time modulations in both the delays. The transition from anticipatory to complete synchronization and from complete to lag synchronization as a function of coupling delay with suitable stability condition is discussed. The intermittent anticipatory and lag synchronizations are characterized by the minimum of similarity functions and the intermittent behavior is characterized by a universal asymptotic $-{3/2}$ power law distribution. It is also shown that the delay time carved out of the trajectories of the time-delay system with periodic delay time modulation cannot be estimated using conventional methods, thereby reducing the possibility of decoding the message by phase space reconstruction.Comment: accepted for publication in CHAOS, revised in response to referees comment

Simulation And Analysis Of Indian Air Traffic

Air Traffic Density In India And The World At Large Is Growing Fast . The Airspace And Air Traffic Management Therefore Need Augmentation Of System Capability Without Compromising Safety . This Report Addresses The Judicious Use Of Simulation Facilities To Predict Present And Futuristic Problems. It Is Intended To Help Service Providers Plan And Come Out With Strategies For Air Traffic Management. "State Of The Art Simulation Facilities Are Also Useful In Training A Team Of Reliable, Safe And Efficient Air Traffic Controllers . The Report Presents Results Of Simulation Of Three International Airports : One Existing In Bangalore, The One Planned At Devanahalli And The One In Cochin . The Problems Addressed Are Those Of Delay Encountered At The Three Airports, Controller Workload And Noise Contours Around The Bangalore Aerodrome

Modelling,simulation, and analysis of HAL Bangalore13; international airport

Air traffic density in India and the world at large is growing fast and posing challenging13; problems. The problems encountered can be parameterized as flight delay, workload of air traffic13; controllers and noise levels in and around aerodromes. Prediction and quantification of these13; parameters aid in developing strategies for efficient air traffic management. In this study, the13; method used for quantifying is by simulation and analysis of the selected aerodrome and air13; space. This paper presents the results of simulation of HAL Bangalore International Airport,13; which is used by civil as well as military aircraft. With the test flying of unscheduled military13; aircraft and the increase in the civil air traffic, this airport is hitting the limit of acceptable delay.13; The workload on air traffic controllers is pushed to high during peak times. The noise contour13; prediction, especially for the test flying military aircraft is sounding a wake up call to the13; communities living in the vicinity of the Airport.13

Phase Synchronization in Unidirectionally Coupled Ikeda Time-delay Systems

Phase synchronization in unidirectionally coupled Ikeda time-delay systems exhibiting non-phase-coherent hyperchaotic attractors of complex topology with highly interwoven trajectories is studied. It is shown that in this set of coupled systems phase synchronization (PS) does exist in a range of the coupling strength which is preceded by a transition regime (approximate PS) and a nonsynchronous regime. However, exact generalized synchronization does not seem to occur in the coupled Ikeda systems (for the range of parameters we have studied) even for large coupling strength, in contrast to our earlier studies in coupled piecewise-linear and Mackey-Glass systems \cite{dvskml2006,dvskml2008}. The above transitions are characterized in terms of recurrence based indices, namely generalized autocorrelation function $P(t)$, correlation of probability of recurrence (CPR), joint probability of recurrence (JPR) and similarity of probability of recurrence (SPR). The existence of phase synchronization is also further confirmed by typical transitions in the Lyapunov exponents of the coupled Ikeda time-delay systems and also using the concept of localized sets.Comment: 10 pages, 7 figure

Mediating effects of broadband consumers’ behavior in India

Internet usage is rapidly growing in areas like cosmopolitan cities, semi-urban cities in India. I-enabled services offered by various government agencies, educational institutions and commercial activities force users of these services to seek superior internet access like broadband, WiMax is likely to replace traditional broadband and dial-up access soon. Interestingly, reforms in telecom sector are taking place at a rapid pace in India. Many private players started internet services affecting monopolistic public sector telecoms. The advent of private ISPs, the consumer behavior and brand choice of broadband consumers are witnessing dynamic shift in favor of private players. Cost competitiveness, transparency, paradigm shift in consumer responsiveness etc weigh in favor of Public Sector telecoms. This paper attempts to identify the factors affecting broadband consumer behavior. Further, paper studies the causes and effects, mediating effects of consumer behavior and conceptualizes a model to capture these effects. The results suggest that adoption of broadband service is playing a mediatory role in consumer satisfaction.Broadband, Adoption, Normative constructs, mediating

Increasing paddy yields and improving farm management: results from participatory experiments with good agricultural practices (GAP) in Tanzania

Rice is an increasingly important commodity in sub-Saharan Africa. In Tanzania, the rice yield gap is as high as 87%, due to a combination of production constraints and sub-optimal crop management. Reducing this yield gap may be partly achieved through the introduction and dissemination of good agricultural practices (GAP). We conducted 18 farmer-managed on-farm trials in Tanzania, to test a set of GAP components against conventional farmers' practices (FP) for two consecutive growing seasons in 2013 and 2014. The objectives were: (1) to understand farmers' capabilities in implementing GAP; (2) to acquire better insights into the merits, relevance and suitability of individual GAP components; and (3) to provide a case study showing that exposure to good practices combined with the farmers' own experimentations can serve to improve and, trigger a positive change in the participating farmers' crop management. Compared to the farmers' own practices, average yield increases of 1 t paddy ha−1 in 2013 and 2.7 t ha−1 in 2014 were achieved when following GAP. These yield advantages were mainly obtained by a higher panicle number, improved harvest index and improved weed control. Farmers experienced difficulties with land levelling, planting or sowing in lines and using rotary weeders, but they were convinced that these technologies are important to boost their rice yields. The case of Tanzania shows that paddy yields can be substantially improved by GAP and that adoption of GAP by smallholder rice farmers can be triggered by stimulating experimentations with such practices on their own farms

Generalizing the transition from amplitude to oscillation death in coupled oscillators

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