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21.
M. A. Pathan M. Kamarujjama M. Khursheed Alam 《Journal of Computational and Applied Mathematics》2003,160(1-2):251-257
This paper aims at presenting multiindices and multivariables study of the unified (or generalized) Voigt functions which play an important rôle in the several diverse field of physics such as astrophysical spectroscopy and the theory of neutron reactions. Some expressions (representations) of these functions are given in terms of familiar special functions of multivariables. Further representations and series expansions involving multidimensional classical polynomials (Laguerre and Hermite) of mathematical physics are established. 相似文献
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Numerical Algorithms - In the present paper, q-analogue of Lupa? Bernstein operators with shifted knots are introduced. First, some basic results for convergence of the introduced operators... 相似文献
24.
Temitope T. Abiola Nazia Auckloo Jack M. Woolley Christophe Corre Stphane Poigny Vasilios G. Stavros 《Molecules (Basel, Switzerland)》2021,26(24)
Plants, as with humans, require photoprotection against the potentially damaging effects of overexposure to ultraviolet (UV) radiation. Previously, sinapoyl malate (SM) was identified as the photoprotective agent in thale cress. Here, we seek to identify the photoprotective agent in a similar plant, garden cress, which is currently used in the skincare product Detoxophane nc. To achieve this, we explore the photodynamics of both the garden cress sprout extract and Detoxophane nc with femtosecond transient electronic absorption spectroscopy. With the assistance of liquid chromatography-mass spectrometry, we determine that the main UV-absorbing compound in garden cress sprout extract is SM. Importantly, our studies reveal that the photoprotection properties of the SM in the garden cress sprout extract present in Detoxophane nc are not compromised by the formulation environment. The result suggests that Detoxophane nc containing the garden cress sprout extract may offer additional photoprotection to the end user in the form of a UV filter booster. 相似文献
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Summary For estimating the mean of ap-variate normal distribution under a quadratic loss, a class of estimators, known as Stein's estimators, is known to dominate
the maximum likelihood estimator (MLE) forp≧3. But, whereas the risk of the MLE has the same value, equal to a constant, for each component, the maximum component risk
of Stein's estimator is large for large values ofp. Certain modification of Stein's rule has been proposed in the literature for reducing the maximum component risk. In this
paper, a new rule is given for reducing the maximum component risk. The new rule yields larger reduction in the maximum component
risk, compared to its competitor. 相似文献
27.
Khursheed Alam 《Annals of the Institute of Statistical Mathematics》1971,23(1):411-418
Summary There are givenk Poisson processes with mean arrival times 1/λ1,...1/λ
k
. Let λ[1]≦λ[2]≦...≦λ[k] denote the ordered set of values λ1...,λ[k]. We consider three procedures for selecting the process corresponding to λ[k]. The processes are observed until there areN arrivals from any of the given processes, when the processes are observed continuously, or until there are at leastN arrivals, when the processes are observed at successive intervals of time whereN is a pre-determined positive integer. In the continuous case, the process for which theNth arrival time is shortest, is selected. In the discrete case, the selection involves certain randomization.
Given (λ[k]/λ[k-1])≧0>1, it is shown that the probability of a correct selection (Pcs) is minimized whenθλ[1]=θλ[2]=...=θλ[k-1]=θλ[k]=θλ, say. The Pcs for this configuration is independent of λ for two of the given procedures, and monotone increasing in λ for
the third. The value ofN is determined by a lower bound placed on the value of the Pcs.
The problem of selecting from given Poisson processes for the discrete case is related to the problem of selecting from given
Poisson populations. An application of the given procedures to a problem of selecting the “most probable event” from a multinomial
population, is considered. 相似文献
28.
Proni G Pescitelli G Huang X Quraishi NQ Nakanishi K Berova N 《Chemical communications (Cambridge, England)》2002,(15):1590-1591
A circular dichroic (CD) excition chirality method based on host-guest chiral recognition has been developed to determine the absolute configuration of carboxylic acids with an alpha-stereogenic center; an amide C = O-->Zn coordination, identified by infrared spectroscopy and computations, is involved in this complexation. 相似文献
29.
Mishra Mahesh Kumar Singh Vedeshwar Narayan Ahmad Khursheed Sharma Sitaram 《Molecular diversity》2021,25(4):2073-2087
Molecular Diversity - A series of novel monocyclic cis-β-lactams were prepared from phenoxyacetic acid as ketene source and imines derived from 1-chloro-3,4-dihydronaphthalene-2-carbaldehyde... 相似文献
30.