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We analyze the underlying dynamics at three different latitudes of ionosphere through total electron content‐series for 4 months. The global dynamics reconstructed from the data is shown to be deterministic with low dimensional chaotic attractors at all the locations, and the dynamics is seen to be less complex at the midlatitude station with smaller dimension of correlation (CD) and maximum Lyapunov exponent (MLE). The influence of geomagnetic storms on the ionospheric dynamics is studied, by analyzing the local dynamics during disturbed and quiet periods, reconstructed from segments of total electron content‐series of shorter duration. With positive MLEs and smaller CDs, the local dynamics is seen to be deterministic and chaotic at the low latitude, midlatitude, and high latitude during both the disturbed and quiet days. However, it is interesting to observe that the dynamics is less chaotic and complex during the disturbed days of the entire period of observation compared to the adjacent quiet days at the three locations. This is further evidenced by sample predictions made using nonlinear tools, yielding better predictions during storms. The smaller CD value during disturbed periods indicates that the geomagnetic activities tend to make a few of the variables dominant enough to control the essential dynamics of the system. Further, the MLEs of the disturbed days are found to increase nearly in a linear fashion from beginning to end of the observation period at all the locations considered. This is an indication of the strong influence of geomagnetic activities on the ionosphere and might have caused the restructuring of the ionospheric dynamics. The TEC dynamics is seen to be less complex at the midlatitudes with smaller correlation dimension (CD) and maximum Lyapunov exponent (MLE)The local dynamics is deterministic and chaotic at all latitudes during storm and quiet days. It is less chaotic and complex at storm daysA few variables are dominant to control the dynamics during geomagnetic activities. The MLEs of disturbed days increase in a linear fashion

Knowledge of wind speed and its characteristics is important for the optimising the production and transmission of wind power generated by wind mills. In this paper, we analyse the frequency component level distribution characteristics of wind speed variations at the locations across Indian sub-continent. The results show significant variation of the distribution behaviour among frequency components. We also analyse effect of location, seasonal variation and temporal position in the solar cycle. The skewness and kurtosis show clear scaling behaviour against latitude showing a decrease as location approaches equator. The impact of solar cycle is more predominant at the locations closer to the equator. The seasonal impact on distribution characteristics is also the evident and more prominent at the locations closer to the equator in solar maximum year.

In this study, aluminium AA6063 6mm thickness plate were welded by friction stir butt joint, the friction stir welding process is an emerging solid state joining processes in which the material that is being welded does not melt. This process uses a non consumable tool to generate a welding. The welding parameter such as tool rotational speed, welding speed, axial force and tool pin profile play a major role in deciding the joint properties. Two different tool pin profiles (Square and pentagon) have been used to fabricate the joints at constant rotational speed 1500rpm. The effect of welding parameter was evaluated in different mechanical properties of hardness distribution and tensile properties for axial weld zone.

This paper presents the results of measurements of the surface ozone (O3), oxides of nitrogen (NOx), methane (CH4) and total non-methane hydrocarbons (TNMHCs) in a rural coastal location at Kannur (11.9°N, 75.4°E, 5 m asl), India from November 2009 to December 2011. The diurnal cycle for surface O3had a peak in the afternoon and declined during nighttime. The maximum and minimum mixing ratio of surface O3was observed in winter and monsoon seasons respectively. NOxconcentration was high during mid-night to early morning and low during noontime. The diurnal variations of mixing ratios for NOxand O3were anti-correlated. Monthly average maximum (2.26 ± 0.44 ppmv) and minimum (0.43 ± 0.19 ppmv) CH4concentrations were observed in December and August respectively. The diurnal variations of CH4were similar to that of NOx. A CH4buildup was observed during early morning hours throughout the observational period. On an annual basis, the maximum, minimum and average total NMHCs were (25.45 ± 6.58 ppbv), (13.84 ± 4.31 ppbv), and (19.23 ± 5.56 ppbv) respectively at the observational site. Analysis of O3, NO, NO2, CH4and NMHC have been carried out and the correlation between O3and its precursors is discussed detailed. Further, the diurnal variation of O3over a free tropospheric region at Ooty, a hill station lying in the Western Ghats region of south India on clear sky days in February 2011 is also reported for a comparison.

Multiple shoot formation from the medicinal plant Plumbago rosea Linn. was induced on callus from stem segments on Murashige & Skoog media containing auxin and cytokinin. 2,4-D (2.5 mg l-1) and kinetin (1.5 mg l-1) added to the media gave best callus production, while BAP (2 mg l-1) plus NAA (1.0 mg l-1) induced shoot formation from that callus. Numerous shoots with roots could be produced by transferring shoots to media containing IBA (1.5 mg l-1). Regenerated plantlets were transferred to pots and 60% survived.

In this paper, we consider the technologically important problem of periodically forced spheroids in simple shear flow and demonstrate the existence of chaotic parametric regimes. The approach used by Strand (1989) (for the Strong Brownian limit) is inappropriate in the chaotic regimes corresponding to the weak Brownian limit. Our results also indicate a strong dependence of the solutions obtained on the aspect ratio of the spheroids. This strong dependence on the aspect ratio may be utilized to separate particles from a suspension of particles having different shapes but similar sizes.

In an earlier paper, we had outlined a procedure for calculating the rheological parameters for periodically forced suspensions of slender rods in simple shear flow in the chaotic regime. In this work, we examine the consequences of the above procedure on the dynamics and rheology of similar suspensions starting off with uniform initial orientation distributions as well as aligned initial distributions. We provide numerical evidence for existence of riddled and intermingled basins of attractions in the system. We discuss the limitations of the diffusion equation approach in the chaotic regime. We also demonstrate that small changes in the preparation of aligned suspensions can lead to dramatically different rheological behaviour in some parametric regimes. In other parametric regimes differences in the dynamical behaviour do not translate into differences in the rheological behaviour of aligned suspensions.