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821.
Govind S. Mudholkar Rajeshwari Natarajan 《Annals of the Institute of Statistical Mathematics》2002,54(1):138-154
The inverse Gaussian (IG) family is strikingly analogous to the Gaussian family in terms of having simple inference solutions, which use the familiar 2, t and F distributions, for a variety of basic problems. Hence, the IG family, consisting of asymmetric distributions is widely used for modelling and analyzing nonnegative skew data. However, the process lacks measures of model appropriateness corresponding to
and 2, routinely employed in statistical analyses. We use known similarities between the two families to define a concept termed IG-symmetry, an analogue of the symmetry, and to develop IG-analogues 1 and 2 of
and 2, respectively. Interestingly, the asymptotic null distributions of the sample versions d
1, d
2 of 1, 2 are exactly the same as those of their normal counterparts
and b
2. Some applications are discussed, and the analogies between the two families, enhanced during this study are tabulated. 相似文献
822.
Natarajan Chidambaram Shanthi Padmanabhan Athappan Periakaruppan Murugesan Ramachandran 《Transition Metal Chemistry》1992,17(1):39-45
Transition Metal Chemistry - Metal(II) chelates of the type ML2nB [M = CoII, NiII and CuII; L = 1-(2-hydroxy-1-naphthyl)-3-(4-X-phenyl)-2-pro-pen-1-one, (X = H, Cl or Me); B = H2O or Py; n = 0, 2]... 相似文献
823.
824.
The mean characteristics of the flow due to mixing of two non-axial plane jets in a confined passage, were reported previously
by Manjunath et al. (Exp. Fluids 11 (1991), 17–24), as part I. In this paper, the turbulence characteristics of the flow are
discussed. The various components of the Reynolds stress tensor are reported for the four inlet angles considered, viz., 15°,
30°, 45° and 60°. As expected from the mean flow field, the inlet angle influences the distribution of the various turbulence
components through the relative size of the recirculation zones and the turbulence field is different for the smaller angles
of 15° and 30° in comparison to those for 45° and 60°. 相似文献
825.
826.
Sunil Jai Kumar S. Natarajan J. Arunachalam S. Gangadharan 《Fresenius' Journal of Analytical Chemistry》1990,338(7):836-840
Summary The determination of Cd, Co, Cu, Fe and Ni in 6N gallium by GFAAS is reported. The analytes are extracted as pyrrolidine dithiocarbamates into methyl-iso-butyl-ketone (MIBK) in the presence of tartrate. The conditions of extraction, quantity of reagents required and the matrix interference aspects are discussed. The method offers one-step matrix removal and preconcentration, leading to low experimental blanks. 相似文献
827.
828.
A K Gupta N S Natarajan V S Tomar N D Kataria V K Batra A V Narlikar K Chandra 《Pramana》1987,28(5):517-527
A C Josephson effect is now used by several countries as the reference standard for the unit of d.c. voltage. This paper describes the work done at the National Physical Laboratory (NPL), New Delhi in the realization of the unit of volt based on the a.c Josephson effect. A voltage standard at 1 mV level using a Nb-Nb point contact junction has been established and the as-maintained volt based on a bank of standard cells has been intercompared against it using a 1:1000 voltage divider. The experimental set-up used in this comparison and the results of recent measurements are described. The overall uncertainty in assigning the value of emf to a standard cell is about 1 ppm. The as-maintained volt has been found to agree with the Josephson voltage within overall uncertainty. 相似文献
829.
T.R. Govindachari N. Viswanathan J. Radhakrishnan B.R. Pai S. Natarajan P.S. Subramaniam 《Tetrahedron》1973,29(6):891-897
The structure of the phenolic alkaloid tylophorinidine, isolated from Tylophora asthmatica, has been shown to be 2. Two other minor alkaloids isolated from the plant have been shown to be d-septicine (11) and d-isotylocrebrine (14). 相似文献
830.
The crystal structure of sarcosine in pure form has been determined at low temperature (135 K). The crystals are othorhombic, space group P2(1)2(1)2(1) with unit cell dimensions a = 6.687(2) A, b = 7.899(3) A, c = 8.607(3) A. On the basis of 988 reflections with intensities larger than 3 sigma (I) the structure was refined to a conventional R-factor of 0.034 to give e.s.d. in bond lengths of 0.002 A and 0.2 degrees in angles. The molecule is extended and exists in the zwitterionic form. There is a small deviation from planarity in the alpha-amino acid group as well as in the main chain. 相似文献