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101.
Efficient and accurate integration of stochastic (partial) differential equations with multiplicative noise can be obtained through a split-step scheme, which separates the integration of the deterministic part from that of the stochastic part, the latter being performed by sampling exactly the solution of the associated Fokker-Planck equation. We demonstrate the computational power of this method by applying it to the most absorbing phase transitions for which Langevin equations have been proposed. This provides precise estimates of the associated scaling exponents, clarifying the classification of these nonequilibrium problems, and confirms or refutes some existing theories. 相似文献
102.
103.
Nearly zero ultraflattened dispersion in photonic crystal fibers 总被引:24,自引:0,他引:24
We present a procedure for achieving photonic crystal fibers with nearly zero ultraflattened group-velocity dispersion. Systematic knowledge of the special guiding properties of these fibers permits the achievement of qualitatively novel dispersion curves. Unlike the behavior of conventional fibers, this new type of dispersion behavior permits remarkably improved suppression of third-order dispersion, particularly in the low-dispersion domain. 相似文献
104.
Analytical modelling of the work flow through flexible manufacturing systems (FMSs), based on closed queueing network models, has been successfully applied to the early stages of design and analysis of FMSs. This paper describes the advantages of using multiple job-class closed queueing networks for modelling realistic situations occurring in FMSs. The general modelling of FMSs by closed queueing networks is first reviewed. The way Solberg's CAN-Q—a single job-class queueing-based package—deals with several part types is clarified. A new model called MULTIQ, allowing multiple pallet types, each of which is used by several part types, is proposed. Results are derived using the data from an existing FMS. The use of the MULTIQ model for optimization purposes is suggested by some examples. 相似文献
105.
N. Perrin 《Solid State Communications》1976,18(7):877-880
The effect of defect phonon scattering on the spatial dependence of the distribution of phonons generated by Joule heating in metal films is studied. This interaction process is shown to significantly modify the dependence on the direction of propagation of the phonon energy density spectrum. 相似文献
106.
107.
András Prékopa 《Mathematical Programming》1973,4(1):202-221
Two stochastic programming decision models are presented. In the first one, we use probabilistic constraints, and constraints involving conditional expectations further incorporate penalties into the objective. The probabilistic constraint prescribes a lower bound for the probability of simultaneous occurrence of events, the number of which can be infinite in which case stochastic processes are involved. The second one is a variant of the model: two-stage programming under uncertainty, where we require the solvability of the second stage problem only with a prescribed (high) probability. The theory presented in this paper is based to a large extent on recent results of the author concerning logarithmic concave measures.This work was supported in part by the Institute of Economic Planning, Budapest.This paper was presented at the 7th Mathematical Programming Symposium 1970, The Hague, The Netherlands, under the title Programming under probabilistic constraints and programming under constraints involving conditional expectations. 相似文献
108.
109.
José Carlos de Souza Kiihl 《Rendiconti del Circolo Matematico di Palermo》1980,29(3):411-419
In this paper we develop a technique to study the homomorphisma: MU * (B U1)→M U*?2 (B U1) defined by assigning to the class off: M→B U 1 the class off oi: N→B U1, wherei: N→M is the submanifold dual tof*(γ1)?f*(γ1), and γ1→B U is the 3 universal line boundle. So that we can present a (σn), where σnis the class of the classifying map of the canonical line boundle overC P n, in terms of the σi’s and chosen generators of Π★(M U). 相似文献
110.
Andréi Zaitsevskii Elena Rykova Nikolai S. Mosyagin Anatoly V. Titov 《Central European Journal of Physics》2006,4(4):448-460
The relativistic effective core potential (RECP) approach combined with the spin-orbit DFT electron correlation treatment
was applied to the study of the bonding of eka-mercury (E112) and mercury with hydrogen and gold atoms. Highly accurate small-core
shape-consistent RECPs derived from Hartree-Fock-Dirac-Breit atomic calculations with Fermi nuclear model were employed. The
accuracy of the DFT correlation treatment was checked by comparing the results in the scalar-relativistic (spin-orbit-free)
limit with those of high level scalar-relativistic correlation calculations within the same RECP model. E112H was predicted
to be slightly more stable than its lighter homologue (HgH). The E112-Au bond energy is expected to be ca. 25–30 % weaker
than that of Hg-Au. The role of correlations and magnetic (spin-dependent) interactions in E112-X and Hg-X (X=H, Au) bonding
is discussed. The present computational procedure can be readily applied to much larger systems and seems to be a promising
tool for simulating E112 adsorption on metal surfaces. 相似文献