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121.
122.
Nonlocal vertex algebras generated by formal vertex operators 总被引:2,自引:0,他引:2
Haisheng Li 《Selecta Mathematica, New Series》2005,11(3-4):349-397
This is the first paper in a series to study vertex algebra-like objects arising from infinite-dimensional quantum groups
(quantum affine algebras and Yangians). In this paper we lay the foundations for this study. For any vector space W, we study what we call quasi compatible subsets of Hom (W,W((x))) and we prove that any maximal quasi compatible subspace has a natural nonlocal (namely noncommutative) vertex algebra
structure with W as a natural faithful quasi module in a certain sense, and that any quasi compatible subset generates a nonlocal vertex algebra
with W as a quasi module. In particular, taking W to be a highest weight module for a quantum affine algebra we obtain a nonlocal vertex algebra with W as a quasi module. We also formulate and study a notion of quantum vertex algebra and we give general constructions of nonlocal
vertex algebras, quantum vertex algebras and their modules. 相似文献
123.
In this paper we obtain a number of Maharam-type slice integral representations, with respect to scalar measures, for positive
projections in Dedekind complete vector lattices and f-algebras.
AMS Classification: 47B65, 46A40, 06F25 相似文献
124.
Within the framework of a piecewise homogeneous body model, with the use of three-dimensional geometrically nonlinear exact equations of elasticity theory, a method for determining the stress—strain state in unidirectional fibrous composites with locally curved fibers is developed for the case where the interaction between the fibers is neglected. All the investigations are carried out for an infinite elastic body containing a single locally curved fiber. Numerical results illustrating the effect of geometrical nonlinearity on the distribution of the self-balanced normal and shear stresses acting on the interface and arising as a result of local curving of the fiber are presented.__________Russian translation published in Mekhanika Kompozitnykh Materialov, Vol. 41, No. 4, pp. 433–448, July–August, 2005. 相似文献
125.
D. K. Kulshrestha 《The Journal of the Operational Research Society》1987,38(5):447-452
Consider a finite set of demand points which exist anywhere on the boundary of a rectangle contained in the two-dimensional Euclidean space. This paper considers the problem of finding an optimal location (on the boundary of the rectangle) which minimizes the maximum average Euclidean distance to the demand points. The method presented is independent of the number of demand points. 相似文献
126.
S. S. Dragomir 《Acta Mathematica Hungarica》2005,109(4):331-345
Summary General divergence measures for probability distributions are introduced and their main properties established. Connections
with f-divergence corresponding to a convex function fare explored. 相似文献
127.
Neodymium doped bismuth layer structure ferroelectrics (BLSFs) ceramics CaBi4−xNdxTi4O15 (x=0, 0.25, 0.50, 0.75) were prepared by solid-state reaction method. X-ray diffraction pattern showed that single phase was formed when x=0-0.75. The refined lattice parameters showed that a (b) axes decrease at x=0.25 and increase with more Nd3+ dopant. The effects of Nd3+ doping on the dielectric and ferroelectric properties of CaBi4Ti4O15 ceramics are studied. Nd3+ dopant decreased the Curie temperature linearly, and the dielectric loss, tan δ, as well. The remnant polarization of Nd3+ doped CaBi4Ti4O15 ceramics was increased by 80% at x=0.25, while more Nd3+ dopant decreased the remnant polarization. CaBi3.75Nd0.25Ti4O15 ceramics had the largest piezoelectric constant d33. The structure and properties of CaBi4−xNdxTi4O15 ceramics showed that Nd3+ may occupy different crystal locations when Nd3+ content x is less than 0.25 and more than 0.50. 相似文献
128.
129.
A nonlinear (in the cubic approximation) relaxation equation of state is derived for a rod containing cracks partially filled with an incompressible viscous liquid. The nonlinear effects of the self-action and interaction of low-and high-frequency longitudinal elastic waves propagating in such a rod are studied for the cases of identical and size-varied cracks. Linear and nonlinear acoustic parameters characterizing the self-action and interaction of elastic waves in a cracked rod are determined. 相似文献
130.
V. A. Nadtochenko A. S. Lobach F. E. Gostev O. M. Sarkisov D. O. Shcherbinin E. D. Obraztsova 《JETP Letters》2004,80(3):176-180
The dynamics of the photoinduced differential absorption and excited-state bleaching spectra of single-walled carbon nanotubes suspended in a micellar solution were studied in the spectral range from 40 to 1000 nm within a time interval from 70 fs to 150 ps under excitation by 50-fs pulses with photon energies 2 and 4 eV. The bleaching and absorption bands were observed in the spectra; the positions of the bleaching peaks were independent of the photon energy of the exciting femtosecond pulse in the range 2–4 eV. It was established that, for delay times shorter than 1 ps, the shape of the differential spectrum of excited nanotubes coincided with the shape of the second derivative of the absorption spectrum of unexcited nanotubes in the frequency range of exciting pulse above 18000 cm?1 (the range of absorption bands of metallic nanotubes). In the frequency range below 16000 cm?1 (the range of absorption peaks of semiconducting nanotubes), the bleaching peaks in the differential spectrum of excited nanotubes undergo a high-frequency shift of 200–300 cm?1 with respect to the second-derivative spectrum of unexcited nanotubes. The excited-state relaxation rate constants were measured. They are well approximated by the exponential dependences and depend on the probe-pulse wavelength. An assumption was made about the nature of the observed spectra of excited nanotubes and about the excitation relaxation. 相似文献