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21.
E. Dowzard M. J. Russo E. B. Hershberg H. T. Dolin W. S. Gilfoil R. Dolique R. C. Ray und V. Dayal 《Fresenius' Journal of Analytical Chemistry》1938,113(5-6):212-213
Ohne Zusammenfassung 相似文献
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Sampat Dayal Jha 《Colloid and polymer science》1955,142(1):45-45
Ohne Zusammenfassung 相似文献
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On allocation of sample using estimates of both proportions of stratum sizes and standard deviations
Shambhu Dayal 《Annals of the Institute of Statistical Mathematics》1980,32(1):433-444
Summary Stratified sampling is the most efficient when the sample is allocated to different strata in proportion to the products of
(i) the proportions of the stratum sizes and (ii) the standard deviations of the variable in various strata (Neyman [2]).
In practice, however, these are not always known. Sometimes, proportions of stratum sizes are not known at the planning stage
but become known at the estimation stage. Comparison of various plans has been made when estimates of these measures are made
use of in the allocation of sample. 相似文献
26.
The temperature variation of the second order Raman spectra of RbI has been theoretically studied in three basic symmetries on the basis of the modified Born and Bradburn theory. The phonon frequencies and corresponding eigenvectors have been determined at the room temperature by employing a three body force shell model. It has been assumed that the major factor which governs the temperature dependence of Raman intensity is the occupation number and the changes in the phonon eigen data and the polarizability parameters with temperature have been ignored. Calculations have been made at three temperatures namely, 300,90 and 23 K and the theoretical results have been compared to the experimental Raman spectra. 相似文献
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28.
Shweta Srivastava Shinoo Srivastava Seema Srivastava Vishwambhar Dayal Gupta Sanjeev John La'Verne 《Journal of Macromolecular Science: Physics》2013,52(1):157-173
A study of the normal modes of vibration and their dispersion in polypyrrole (PPY) based on the Urey-Bradley force field is reported. It gives a fuller interpretation of previously reported FTIR spectra. Characterstic features of dispersion curves, such as regions of high density-of-states, repulsion, and character mixing of dispersive modes, are discussed. Predictive values of heat capacity as a function of temperature are reported. 相似文献
29.
Smita Dayal Jun Li Ying-Syi Li Hongqiao Wu Anna C S Samia Malcolm E Kenney Clemens Burda 《Photochemistry and photobiology》2008,84(1):243-249
This study examines the electronic coupling between quantum dots (QDs) and molecules on their surfaces as a function of the modality of their interaction. As a probe, the energy transfer (ET) between CdSe QDs and phthalocyanines (Pcs) was monitored and evaluated with regard to the functionalization of the axial phthalocyanine ligand, bulkiness of the functional group bridging the QD donor and Pc acceptor, and the number of the functionalized axial ligands. New silicon PCs and their conjugates with CdSe QDs were synthesized. The ET efficiency and kinetics were studied by steady state and femtosecond time-resolved absorption spectroscopy. We observed a decrease in ET efficiency with the increase in functional group bulkiness, which could be explained by increasing steric hindrance between the ET pair. In addition, a higher ET efficiency was observed for amino and thiol functionalized Pcs compared to Pcs without functional group on the axial alkyl chain. 相似文献
30.
The current research work has employed an evolutionary based novel navigational strategy to trace the collision free near optimal path for underwater robot in a three-dimensional scenario. The population based harmony search algorithm has been dynamically adapted and used to search next global best pose for underwater robot while obstacle is identified near about robot’s current pose. Each pose is evaluated based on their respective value for objective function which incorporates features of path length minimization as well as obstacle avoidance. Dynamic adaptation of control parameters and new perturbation schemes for solution vectors of harmony search has been proposed to strengthen both exploitation and randomization ability of present search process in a balanced manner. Such adaptive tuning process has found to be more effective for avoiding early convergence during underwater motion in comparison with performances of other popular variants of Harmony Search. The proposed path planning method has also shown better navigational performance in comparison with improved version of ant colony optimization and heuristic potential field method for avoiding static obstacles of different shape and sizes during underwater motion. Simulation studies and corresponding experimental verification for three-dimensional navigation are performed to check the accuracy, robustness and efficiency of proposed dynamically adaptive harmony search algorithm. 相似文献