Zobrazeno 1 - 10
of 39
pro vyhledávání: '"Hatchett, J. P. L."'
Autor:
Hatchett, J. P. L., Inoue, Jun-ichi
We evaluate the average number of locally minimal solutions for maximum-{\it a-posteriori} (MAP) demodulation in code-division multiple-access (CDMA) systems. For this purpose, we use a sophisticated method to investigate the ground state properties
Externí odkaz:
http://arxiv.org/abs/cond-mat/0701638
Autor:
Hatchett, J. P. L., Kuehn, R.
We study a simple, solvable model that allows us to investigate effects of credit contagion on the default probability of individual firms, in both portfolios of firms and on an economy wide scale. While the effect of interactions may be small in typ
Externí odkaz:
http://arxiv.org/abs/physics/0609164
Autor:
Giuraniuc, C. V., Hatchett, J. P. L., Indekeu, J. O., Leone, M., Castillo, I. Perez, Van Schaeybroeck, B., Vanderzande, C.
Publikováno v:
Physical Review E 74, 036108 (2006)
Weighted scale-free networks with topology-dependent interactions are studied. It is shown that the possible universality classes of critical behaviour, which are known to depend on topology, can also be explored by tuning the form of the interaction
Externí odkaz:
http://arxiv.org/abs/cond-mat/0603689
Autor:
Skantzos, N. S., Hatchett, J. P. L.
We study the Lebwohl-Lasher model for systems in which spin are arranged on random graph lattices. At equilibrium our analysis follows the theory of spin-systems on random graphs which allows us to derive exact bifurcation conditions for the phase di
Externí odkaz:
http://arxiv.org/abs/cond-mat/0602666
Autor:
Hatchett, J. P. L., Kuehn, R.
We study a credit risk model which captures effects of economic interactions on a firm's default probability. Economic interactions are represented as a functionally defined graph, and the existence of both cooperative, and competitive, business rela
Externí odkaz:
http://arxiv.org/abs/physics/0512155
Autor:
Hatchett, J. P. L., Okada, M.
Publikováno v:
J. Phys. A: Math. Gen. (2006) 39 3883-3902
We investigate the detection dynamics of the Gibbs sampler for code-division multiple access (CDMA) multiuser detection. Our approach is based upon dynamical replica theory which allows an analytic approximation to the dynamics. We use this tool to i
Externí odkaz:
http://arxiv.org/abs/cond-mat/0512036
Publikováno v:
Phys. Rev. E (2005) 72, 066105
We investigate equilibrium properties of small world networks, in which both connectivity and spin variables are dynamic, using replicated transfer matrices within the replica symmetric approximation. Population dynamics techniques allow us to examin
Externí odkaz:
http://arxiv.org/abs/cond-mat/0508250
Autor:
Coolen, A., Skantzos, N. S., Castillo, I. Perez, Vicente, C. J. Perez, Hatchett, J. P. L., Wemmenhove, B., Nikoletopoulos, T.
We use finite connectivity equilibrium replica theory to solve models of finitely connected unit-length vectorial spins, with random pair-interactions which are of the orthogonal matrix type. Since the spins are continuous and the connectivity c rema
Externí odkaz:
http://arxiv.org/abs/cond-mat/0504690
Publikováno v:
Phys. Rev. Lett. (2005) 95, 117204
We study the dynamics of macroscopic observables such as the magnetization and the energy per degree of freedom in Ising spin models on random graphs of finite connectivity, with random bonds and/or heterogeneous degree distributions. To do so we gen
Externí odkaz:
http://arxiv.org/abs/cond-mat/0504313
Autor:
Giuraniuc, C. V., Hatchett, J. P. L., Indekeu, J. O., Leone, M., Castillo, I. Perez, Van Schaeybroeck, B., Vanderzande, C.
Publikováno v:
Physical Review Letters 95, 098701 (2005) (4pages)
Scale-free networks with topology-dependent interactions are studied. It is shown that the universality classes of critical behavior, which conventionally depend only on topology, can also be explored by tuning the interactions. A mapping, $\gamma' =
Externí odkaz:
http://arxiv.org/abs/cond-mat/0408399