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81.
LetG be a connected Poisson-Lie group. We discuss aspects of the question of Drinfel'd:can G be quantized? and give some answers. WhenG is semisimple (a case where the answer isyes), we introduce quantizable Poisson subalgebras ofC ∞(G), related to harmonic analysis onG; they are a generalization of F.R.T. models of quantum groups, and provide new examples of quantized Poisson algebras. 相似文献
82.
Philip Birch Gongde Li Frederic Claret-Tournier Rupert Young Chris Chatwin 《Optics and Lasers in Engineering》2004,41(6):919-926
Two optical lenses are used to compose a surface position measuring system. A measurand is positioned near the front focal point of the first lens. At the output end of the other lens, a beam splitter is used to split the beam into two paths. One photodetector is positioned before the focal point of the lens in one path and another after the focal point in the other so that the intensities falling onto the two detectors can be adjusted to be equal when the first lens is in focus. This device provides a compact and high-accuracy surface sensor. In this paper, the design and experimental study of the sensor system is described. It is shown that such a sensor embodiment can lead to a resolution of 1 μm. 相似文献
83.
Grandeury A. Renou L. Dufour F. Petit S. Gouhier G. Coquerel G. 《Journal of Thermal Analysis and Calorimetry》2004,77(2):377-390
The crystallization behaviour and the physical characterization of supramolecular complexes formed between permethylated-α-cyclodextrin
(TMα-CD) and the enantiomers of phenylethanol (PE) are investigated. According to crystal structure analyses, complexes containing
the pure guest enantiomers are almost isomorphous, indicating that the host presents a poor ability to distinguish PE enantiomers
at a molecular level. Nevertheless, crystallizations from racemic PE in water induce an efficient chiral discrimination and
allow the enantio-separation of the guests despite the existence of a solid solution revealed by XRPD and coupled TG-DSC analyses.
The enantiodifferentiation is explained by solubility differences between the two diastereomeric complexes in the studied
temperature range. Moreover, it is shown that the diastereomeric complex TMα-CD/(S)-PE crystallizes in two distinct phases: a monohydrate and an anhydrous form, with a transition temperature close to 37°C.
The insertion of a water molecule in the crystals grown below 37°C does not involve any other change of the crystal packing
nor of the molecular conformation, but leads to different crystal growth mechanisms inducing different morphologies and distinct
thermal behaviours.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
84.
Frederic Paik Schoenberg 《Annals of the Institute of Statistical Mathematics》2006,58(2):223-233
Simple point processes are often characterized by their associated compensators or conditional intensities. Non-simple point
processes are not uniquely determined by their conditional intensity and compensator, so instead one may identify with the
point process its associated simple point process and corresponding conditional intensity, on an expanded mark space. Some
relations between the conditional intensity on the expanded mark space and the ordinary conditional intensity are investigated
here, and some classes of separable non-simple processes are presented. Transformations into simple point processes, involving
thinning and rescaling, are presented. 相似文献
85.
Frederic Y. M. Wan 《Studies in Applied Mathematics》1993,89(1):63-94
The method of decaying residual solution is applied to obtain an approximate interior solution for the torsion of slender prismatic elastic bodies under different end conditions. The approximate solution is generally accurate up to terms that are exponentially small in the length-to-cross-sectional-width ratio. For stress end conditions, the result is identical to the classical Saint-Venant torsion solution. Similar types of simple solutions, not known previously, are obtained for different types of mixed end conditions. For displacement conditions at both ends, the corresponding Saint-Venant type result requires an accurate solution of a canonical problem for a semi-infinite prismatic body that is to be obtained once and for all. The solution of the canonical problem is elementary for a circular cross section. The approximate interior solution in that case is identical to the known exact interior solution. 相似文献
86.
87.
Hanif D. Sherali Allen L. Soyster Frederic H. Murphy Suvrajeet Sen 《European Journal of Operational Research》1982,11(4):349-360
This paper concerns methods for discretizing and approximating the annual load duration curve in the context of a linear programming model and its interpretation in electric utility expansion planning. The emphasis is upon the interpretation of the linear programming dual variables and their relationship with classical results of peak load pricing. In particular, for capacity planning in which one can choose from a diverse number of technological alternatives, we support the work of Wenders by precisely characterizing how off-peak periods bear partial responsibility of the capacity cost. 相似文献
88.
89.
Frederic Y. M. Wan 《Studies in Applied Mathematics》1977,56(3):219-239
Simple but accurate approximate solutions for R. M. Solow's theory of urban land rent with congest cost of transportation are obtained by perturbation and asymptotic methods. Only the case of an absentee landlord is discussed though the techniques used can be modified in a straightforward manner to handle the more interesting (and mathematically more complicated) case of municipal ownership. Solow's model is also extended to have expenditures for housing and space as separate items in the budget equation. This extension eliminates the ambiguity in the value for the fraction of income after travel cost spent on ground rent, without affecting the structure of the mathematical problems associated with Solow's original theory. 相似文献
90.
Classical and quantum theories of radiation damping in ferromagnetic and antiferromagnetic resonance
Both classical and quantum theories of radiation damping in ferromagnetic and antiferromagnetic resonance relaxation are given. Effects of demagnetization and anisotropy, that is, of elliptical classical precession, are included. In the classical theory a phenomenological approach to ferromagnetic resonance relaxation by means of the Landau-Lifshitz equation is also presented. In the quantum theory, the magnon-photon interaction Hamiltonian is derived, and the radiation-damped linewidth is obtained by computing the transition matrix element and also the one-magnon self energy. As noted long ago by Einstein, each photon is emitted in a random but specific direction, and only on average does the quantum radiation pattern reproduce the classical. To first order, however, this reproduction is shown to be exact, correcting a recent calculation by Shrivastava. 相似文献