5,883 research outputs found
Warabandi in Pakistan's canal irrigation systems: Widening gap between theory and practice
Irrigation scheduling / Irrigation systems / Irrigation canals / Privatization / Water rights / Social aspects / Economic aspects / Watercourses / Water supply / Equity / Water distribution / Water users' associations / Pakistan / Punjab
Institutional perspectives of land reclamation operations in Punjab: A case study of the Lower Chenab Canal (East) Circle Area
Land reclamationSoil salinityIrrigated sitesIrrigation canalsIrrigation waterInstitutionsLegal aspectsIrrigation schedulingWater availabilityIrrigated farmingCase studies
Dirac versus Reduced Quantization of the Poincar\'{e} Symmetry in Scalar Electrodynamics
The generators of the Poincar\'{e} symmetry of scalar electrodynamics are
quantized in the functional Schr\"{o}dinger representation. We show that the
factor ordering which corresponds to (minimal) Dirac quantization preserves the
Poincar\'{e} algebra, but (minimal) reduced quantization does not. In the
latter, there is a van Hove anomaly in the boost-boost commutator, which we
evaluate explicitly to lowest order in a heat kernel expansion using zeta
function regularization. We illuminate the crucial role played by the gauge
orbit volume element in the analysis. Our results demonstrate that preservation
of extra symmetries at the quantum level is sometimes a useful criterion to
select between inequivalent, but nevertheless self-consistent, quantization
schemes.Comment: 24 page
Iron(III)-catalyzed chlorination of activated arenes
A general and regioselective method for the chlorination of activated arenes has been developed. The transformation uses iron(III) triflimide as a powerful Lewis acid for the activation of N-chlorosuccinimide and the subsequent chlorination of a wide range of anisole, aniline, acetanilide and phenol derivatives. The reaction was utilized for the late-stage mono- and di-chlorination of a range of target compounds such as the natural product nitrofungin, the antibacterial agent chloroxylenol and the herbicide chloroxynil. The facile nature of this transformation was demonstrated with the development of one-pot tandem iron-catalyzed dihalogenation processes allowing highly regioselective formation of different carbon-halogen bonds. The synthetic utility of the resulting dihalogenated aryl compounds as building blocks was established with the synthesis of natural products and pharmaceutically relevant targets
Policy Constraints And Strategic Choices: MNE Subsidiaries Market Penetration In China
This study describes how firm level decisions and capabilities correspond to policy conditions in a host country where local market access is constrained and success is contingent on compliance with cultural hegemony. Using data from surveys gathered from multinational enterprise (MNE) subsidiaries operating in China, we describe the mode of entry the firms have used to penetrate and exploit markets in light of the constrained strategic choices open to their subsidiaries. We also expose the patterns of growth accomplished by the MNE and their underlying bases of competitive advantage. Finally, we relate the degree of centralization we observe among the respondents strategies
Scene Context Dependency of Pattern Constancy of Time Series Imagery
A fundamental element of future generic pattern recognition technology is the ability to extract similar patterns for the same scene despite wide ranging extraneous variables, including lighting, turbidity, sensor exposure variations, and signal noise. In the process of demonstrating pattern constancy of this kind for retinex/visual servo (RVS) image enhancement processing, we found that the pattern constancy performance depended somewhat on scene content. Most notably, the scene topography and, in particular, the scale and extent of the topography in an image, affects the pattern constancy the most. This paper will explore these effects in more depth and present experimental data from several time series tests. These results further quantify the impact of topography on pattern constancy. Despite this residual inconstancy, the results of overall pattern constancy testing support the idea that RVS image processing can be a universal front-end for generic visual pattern recognition. While the effects on pattern constancy were significant, the RVS processing still does achieve a high degree of pattern constancy over a wide spectrum of scene content diversity, and wide ranging extraneousness variations in lighting, turbidity, and sensor exposure
N′-(2,4-Dinitrophenyl)acetohydrazide
In the title compound, C8H8N4O5, the nitro groups ortho and para to the hydrazone group are twisted by 10.0 (2) and 3.6 (2)°, respectively, relative to the aromatic ring. The structure exhibits an intramolecular N—H⋯O hydrogen bond between the hydrazide and ortho-nitro groups. There is a strong intermolecular C=O⋯H—N hydrogen bond, giving rise to chains, and weaker ONO⋯NO2 [2.944 (2) Å] and C—H⋯O—N interactions linking the molecules into a three-dimensional network
Smart Image Enhancement Process
Contrast and lightness measures are used to first classify the image as being one of non-turbid and turbid. If turbid, the original image is enhanced to generate a first enhanced image. If non-turbid, the original image is classified in terms of a merged contrast/lightness score based on the contrast and lightness measures. The non-turbid image is enhanced to generate a second enhanced image when a poor contrast/lightness score is associated therewith. When the second enhanced image has a poor contrast/lightness score associated therewith, this image is enhanced to generate a third enhanced image. A sharpness measure is computed for one image that is selected from (i) the non-turbid image, (ii) the first enhanced image, (iii) the second enhanced image when a good contrast/lightness score is associated therewith, and (iv) the third enhanced image. If the selected image is not-sharp, it is sharpened to generate a sharpened image. The final image is selected from the selected image and the sharpened image
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