Population Mean Estimation with Sub Sampling the Non-Respondents Using Two Phase Sampling

The problem of non-response in double (or two phase) sampling is dealt with combined ratio, product and regression estimators. Expressions of bias and MSE for these estimators are obtained. Comparisons of a proposed strategy with a usual unbiased estimator and other estimators are carried out and results obtained are illustrated numerically using an empirical sample

An Efficient Computational Method for Solving a System of FDEs via Fractional Finite Difference Method

This paper aims to provide a numerical method for solving systems of fractional (Caputo sense) differential equations (FDEs). This method is based on the fractional finite difference method (FDM), where we implemented the Grünwald-Letnikov’s approach. This method is computationally very efficient and gives very accurate solutions. In this study, the stability of the obtained numerical scheme is given. The numerical results show that the proposed approach is easy to be implemented and are accurate when applied to system of FDEs. The method introduces promising tool for solving many systems of FDEs. Two examples are given to demonstrate the applicability and the effectiveness of our method

Effect of dates of sowing and varieties on yield and quality of cluster bean (Cyamopsistetra gonoloba L.)

A field experiment was conducted at Agricultural College Farm, Bapatla (Andhra Pradesh), study the effect of different sowing dates on the yield and quality of different varieties of clusterbean. The experiment was laid out in factorial randomized block design replicated thrice, six dates of sowing from 15th September to 1st December at fifteen days interval and two clusterbean varieties viz. RGC-936 and RGC-1003. Results revealed that growth parameters, yield attributes, yield (1568 kg ha-1) and quality parameters viz. gum content (31.6 %), protein content (30.1 %) and viscosity (3783 cP) were highest with RGC-1003 sown at 15thNovember, which was at par with 1st December sowing with same variety. The study results showed that the clusterbean crop can be grown successfully in non-traditional area as a rabi crop

Large-amplitude chirped coherent phonons in tellurium mediated by ultrafast photoexcited carrier diffusion

We report femtosecond time-resolved reflectivity measurements of coherent phonons in tellurium performed over a wide range of temperatures (3K to 296K) and pump laser intensities. A totally symmetric A$_{1}$ coherent phonon at 3.6 THz responsible for the oscillations in the reflectivity data is observed to be strongly positively chirped (i.e, phonon time period decreases at longer pump-probe delay times) with increasing photoexcited carrier density, more so at lower temperatures. We show for the first time that the temperature dependence of the coherent phonon frequency is anomalous (i.e, increasing with increasing temperature) at high photoexcited carrier density due to electron-phonon interaction. At the highest photoexcited carrier density of $\sim$ 1.4 $\times$ 10$^{21}$cm$^{-3}$ and the sample temperature of 3K, the lattice displacement of the coherent phonon mode is estimated to be as high as $\sim$ 0.24 \AA. Numerical simulations based on coupled effects of optical absorption and carrier diffusion reveal that the diffusion of carriers dominates the non-oscillatory electronic part of the time-resolved reflectivity. Finally, using the pump-probe experiments at low carrier density of 6 $\times$ 10$^{18}$ cm$^{-3}$, we separate the phonon anharmonicity to obtain the electron-phonon coupling contribution to the phonon frequency and linewidth.Comment: 22 pages, 6 figures, submitted to PR

Dynamics of Team Teaching and Research in a Management School: Learning and Imperatives

This paper discusses the experience of team teaching to address the issues of integration of academic inputs by bringing multi-disciplinary perspective together and thereby enhance learning experience of participants. The paper delves on the process, events and outcome of team teaching by four faculty members at IIM Ahmedabad who collaborated in teaching, writing cases, and doing research for a period of more than three years. The experience has been summarized using the following dimensions: need for team-teaching, existing mechanisms and barriers, opportunities and potential, imperatives, fall-outs and challenges experienced in the process. The cohesion, trust and mutual respect are key imperatives. The other factors contributing to the success of team-teaching are strong felt need by the members for integration in programmes, complementary skills and experiences of team members, frequent programmes with integrated components that provided continuous opportunities for learning, co-location of the instructors, and off-site programmes that provided opportunities for close get-togethers. The autonomy granted by the institution to instructors and co-coordinators to design and execute learning opportunities was also instrumental in the success. In an environment where the rule of the game is individualism, forming teams creates fears of loss of importance and recognition. The experience shows that the competency of the members and the overall effectiveness of the tasks are strengthened if the team believes in “reciprocating interdependence”. This can be possible only if members allow themselves opportunities to experiment, improvise and review