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31.
The paper introduces the recent results related to an entropy functional on trajectories of a controlled diffusion process, expressed through an additive functional of the diffusion process, with a Lagrangian, determined by the parameters of a controlled stochastic equation. These results include a minimum condition for the entropy functional and the functional's Jensen inequality, which both are useful for the solution of important mathematical and applied problems.  相似文献   
32.
We present a clustering method for collections of graphs based on the assumptions that graphs in the same cluster have a similar role structure and that the respective roles can be founded on implicit vertex types. Given a network ensemble (a collection of attributed graphs with some substantive commonality), we start by partitioning the set of all vertices based on attribute similarity. Projection of each graph onto the resulting vertex types yields feature vectors of equal dimensionality, irrespective of the original graph sizes. These feature vectors are then subjected to standard clustering methods. This approach is motivated by social network concepts, and we demonstrate its utility on an ensemble of personal networks of migrants, where we extract structurally similar groups and show their resemblance to predicted acculturation strategies.  相似文献   
33.
34.
The Matsubara diagram technique is used to study the formation and thermodynamic properties of an electron-hole liquid (EHL) in the two-dimensional system in the transverse strong magnetic field. The system has discrete energy spectra, i.e. a motion of particles becomes “zero-dimensional”. Therefore, the exchange interaction alone is sufficient to form EHL, the correlation correction being negligible.  相似文献   
35.
In the thermolysis of the silaterazolines silatetrazoline tBu2SiNSiCltBu2 · tBu3SiN3 the silanimine tBu2SiNSiCltBu2 and the silyl azide tBu3SiN3 are formed quantitatively. The silanimine tBu2SiNSiCltBu2 has been trapped with Et3NHF, Me3NHCl, water, 1-butene, 2,3-dimethyl-1,3-butadiene, isobutene, methylvinyl ether, and tBu2SiClN3. The structure of the disiloxane (tBu2SiCl-NH-SitBu2)2O and of the bis(di-tert-butylchlorsilyl)-substituted silatetrazoline tBu2SiNSiCltBu2 · tBu2SiClN3 has been determined by X-ray structure analysis.  相似文献   
36.
The paper introduces a new approach to dynamic modeling, using the variation principle, applied to a functional on trajectories of a controlled random process, and its connection to the process' information functional. In [V.S. Lerner, Dynamic approximation of a random information functional, J. Math. Anal. Appl. 327 (1) (2007) 494-514, available online 5-24-06], we presented the information path functional with the Lagrangian, determined by the parameters of a controlled stochastic equation. In this paper, the solution to the path functional's variation problem provides both a dynamic model of a random process and the model's optimal control, which allows us to build a two-level information model with a random process at the microlevel and a dynamic process at the macrolevel. A wide class of random objects, modeled by the Markov diffusion process and a common structure of the process' information functional, leads to a universal information structure of the dynamic model, which is specified and identified on a particular object with the applied optimal control functions. The developed mathematical formalism, based on classical methods, is aimed toward the solution of problems identification, combined with an optimal control synthesis, which is practically implemented and also demonstrated in the paper's example.  相似文献   
37.
The regions of convergence of Feynman integrals ofp-adic arguments in the coordinate and momentum spaces are established, and a theorem on the Fourier transformation of Feynman amplitudes is proved.State University, Kazan. Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 102, No. 3, pp. 367–377, March, 1995.  相似文献   
38.
A procedure for obtaining explicit expressions for Feynman integrals ofp-adic argument in momentum space is described, and the connection with Feynman amplitudes over a finite field and chromatic polynomials is indicated. Simple explicit expressions are given for the results of integration over the region of large and small momenta.Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 104, No. 3, pp. 371–392, September, 1995.  相似文献   
39.
Silicon analogues of the most prominent carbon nanostructures, namely, hollow spheroidals such as C60 and the fullerene family, have been unknown to date. Herein we show that discrete Si20 dodecahedra, stabilized by an endohedral guest and valence saturation, are accessible in preparative yields through a chloride‐induced disproportionation reaction of hexachlorodisilane in the presence of tri(n‐butyl)amine. X‐ray crystallography revealed that each silicon dodecahedron contains an endohedral chloride ion that imparts a net negative charge. Eight chloro substituents and twelve trichlorosilyl groups are attached to the surface of each cluster in a strictly regioregular arrangement, a thermodynamically preferred substitution pattern according to quantum‐chemical assessment. Our results demonstrate that the wet‐chemical self‐assembly of a complex, monodisperse Si nanostructure is possible under mild conditions starting from simple Si2 building blocks.  相似文献   
40.
Herein we show that replacing the two meso carbon atoms of the polycyclic aromatic hydrocarbon (PAH) bisanthene by boron atoms transforms a near‐infrared dye into an efficient blue luminophore. This observation impressively illustrates the impact of boron doping on the frontier orbitals of PAHs. To take full advantage of this tool for the targeted design of organic electronic materials, the underlying structure–property relationships need to be further elucidated. We therefore developed a modular synthesis sequence based on a Peterson olefination, a stilbene‐type photocyclization, and an Si–B exchange reaction to substantially broaden the palette of accessible polycyclic aromatic organoboranes and to permit a direct comparison with their PAH congeners.  相似文献   
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