688 research outputs found

    Rural Employment Diversification in India: Trends, Determinants and Implications on Poverty

    Get PDF
    This paper has studied rural employment diversification in India and across major states using NSSO data at household level for the period 1983 and 2009-10. Factors affecting rural employment diversification towards non-farm sector have also been studied. Analysis has shown that the non-farm sector has consistently grown over time and employed nearly one-third of the rural workforce in 2009-10, as compared to merely one-fifth in 1983 at all-India level. The similar trend is seen across major states as well, though the pace and pattern varied widely. In providing employment to rural workforce, increasing dominance of crop production, followed by animal husbandry was observed across major states during 2009-10. The share of fishery and forestry was negligible in providing employment to the rural workforce. The study has revealed that the increasing rural non-farm employment has positive and significant effect on reducing rural poverty at all-India level. A positive link between income and employment has also been observed in diversifying towards horticultural activities. A well designed area-specific programme should be evolved to help improve skill of rural workforce, which in turn would benefit in getting employment in the non-farm sector.Rural employment, Employment diversification, Crop sector, Agricultural and Food Policy, J21, J23, O15, O18,

    Concept design, analysis, and Integration of the new U.P.C. multispectral lidar system

    Get PDF
    The increasing need for range-resolved aerosol and water-vapour atmospheric observation networks worldwide has given rise to multi-spectral LIDARs (Light Detection and Ranging, a synonym of laser radar) as advanced remote sensing sensors. This Ph.D. presents the design, integration and analysis of the new 6-channel multispectral elastic/Raman LIDAR for aerosol and water-vapour content monitoring developed at the Remote Sensing Lab. (RSLAB) of the Universitat Polit ecnica de Catalunya (UPC). It is well known that the combination of at least three elastic and two Raman nitrogen channels are su cient to enable retrieval of the optical and microphysical properties of aerosols with a key impact on climate change variables. The UPC lidar is part of the EARLINET (European Aerosol Research Lidar Network) -GALION (Global Atmospheric Watch Atmospheric Lidar Observation Network), a ground-based continental network including more than 28 stations. Currently, only 8 of the 28 EARLINET stations are of such advanced type. This Ph.D. speci cally focuses on: (1) Concept link-budget instrument design and overlap factor assessment. The former includes opto-atmospheric parameter modelling and assessment of backscattered power and SNR levels, and maximum system range for the di erent reception channels (3 elastic, and 2 aerosol and 1 water-vapour Raman channels, ultraviolet to near-infrared bands). The latter studies the laser-telescope crossover function (or overlap function) by means of a novel raytracing Gaussian model. The problem of overlap function computation and its near-range sensitivity for medium size aperture (f=10, f=11) bi-axial tropospheric lidar systems using both detector and ber-optics coupling alternatives at the telescope focal-plane is analysed using this new ray-tracing approach, which provides a much simpler solution than analyticalbased methods. Sensitivity to laser divergence, eld-lens and detector/ ber positions, and ber's numerical aperture is considered. (2) Design and opto-mechanical implementation of the 6-channel polychromator (i.e., the spectrally selective unit in reception). Design trade-o s concerning light collimation, end-to-end transmissivity, net channel responsivity, and homogeneous spatial light distribution onto the detectors' active area discussed. (3) System integration and validation. This third part is two fold: On one hand, fi rst-order backscatter-coe cient error bounds (a level-1 data product) for the two-component elastic lidar inversion algorithm are estimated for both random (observation noise) and systematic error sources (user's uncertainty in the backscatter-coe cient calibration, and user's uncertainty in the aerosol extinction-to-backscatter lidar ratio). On the other hand, the multispectral lidar so far integrated is described at both hardware and control software level. Statistical validation results for the new UPC lidar (today in routine operation) in the framework of SPALI-2010 intercomparison campaign are presented as part of EARLINET quality assurance / optimisation of instruments' program. The methodology developed in the rst part of this Ph.D. has successfully been applied to the speci cation case study of the IFAE/UAB lidar system, which will be installed and operated at the Cherenkov Telescope Array (CTA) observatory. Finally, specs for automated unmanned unattended lidar operation with service times close to 365/24 are presented at the end of this Ph.D. in response to the increasing demand for larger observation times and availability periods of lidar stations

    Primordial power spectrum: a complete analysis with the WMAP nine-year data

    Full text link
    We have improved further the error sensitive Richardson-Lucy deconvolution algorithm making it applicable directly on the un-binned measured angular power spectrum of Cosmic Microwave Background observations to reconstruct the form of the primordial power spectrum. This improvement makes the application of the method significantly more straight forward by removing some intermediate stages of analysis allowing a reconstruction of the primordial spectrum with higher efficiency and precision and with lower computational expenses. Applying the modified algorithm we fit the WMAP 9 year data using the optimized reconstructed form of the primordial spectrum with more than 300 improvement in \chi^2 with respect to the best fit power-law. This is clearly beyond the reach of other alternative approaches and reflects the efficiency of the proposed method in the reconstruction process and allow us to look for any possible feature in the primordial spectrum projected in the CMB data. Though the proposed method allow us to look at various possibilities for the form of the primordial spectrum, all having good fit to the data, proper error-analysis is needed to test for consistency of theoretical models since, along with possible physical artefacts, most of the features in the reconstructed spectrum might be arising from fitting noises in the CMB data. Reconstructed error-band for the form of the primordial spectrum using many realizations of the data, all bootstrapped and based on WMAP 9 year data, shows proper consistency of power-law form of the primordial spectrum with the WMAP 9 data at all wave numbers. Including WMAP polarization data in to the analysis have not improved much our results due to its low quality but we expect Planck data will allow us to make a full analysis on CMB observations on both temperature and polarization separately and in combination.Comment: 19 pages, 5 figures, discussions extended, results unchanged, matches the final version published in JCAP. Note: JCAP published version contains minor typesetting errors (introduced by JCAP at the proof stage) in the plot label

    Sharp inflaton potentials and bi-spectra: Effects of smoothening the discontinuity

    Full text link
    Sharp shapes in the inflaton potentials often lead to short departures from slow roll which, in turn, result in deviations from scale invariance in the scalar power spectrum. Typically, in such situations, the scalar power spectrum exhibits a burst of features associated with modes that leave the Hubble radius either immediately before or during the epoch of fast roll. Moreover, one also finds that the power spectrum turns scale invariant at smaller scales corresponding to modes that leave the Hubble radius at later stages, when slow roll has been restored. In other words, the imprints of brief departures from slow roll, arising out of sharp shapes in the inflaton potential, are usually of a finite width in the scalar power spectrum. Intuitively, one may imagine that the scalar bi-spectrum too may exhibit a similar behavior, i.e. a restoration of scale invariance at small scales, when slow roll has been reestablished. However, in the case of the Starobinsky model (viz. the model described by a linear inflaton potential with a sudden change in its slope) involving the canonical scalar field, it has been found that, a rather sharp, though short, departure from slow roll can leave a lasting and significant imprint on the bi-spectrum. The bi-spectrum in this case is found to grow linearly with the wavenumber at small scales, a behavior which is clearly unphysical. In this work, we study the effects of smoothening the discontinuity in the Starobinsky model on the scalar bi-spectrum. Focusing on the equilateral limit, we analytically show that, for smoother potentials, the bi-spectrum indeed turns scale invariant at suitably large wavenumbers. We also confirm the analytical results numerically using our newly developed code BINGO. We conclude with a few comments on certain related points.Comment: v1: 28 pages, 4 figures; v2: 29 pages, 4 figures, Version to appear in JCA
    corecore