A new network model is proposed to describe the $1/f^\\alpha$ resistance noise of a resistor in non-equilibrium stationary states for a wide range of $\\alpha$ values ($0< \\alpha < 2$). The network is made by different species of resistors, distinguished by their resistances and by their energies associated with thermally activated processes of breaking and recovery. The correlation behavior of the resistance fluctuations is analyzed as a function of temperature and applied current, in both the frequency and time domains. For the noise exponent, the model provides $0< \\alpha < 1$\
at low currents, in the Ohmic regime at a given temperature, with $\\alpha$ decreasing at higher temperatures, and $1< \\alpha <2$ at high currents in the non-Ohmic regime. Since the threshold current associated with the onset of nonlinearity depends also on temperature, the proposed model qualitatively accounts for the complicate behavior of $\\alpha$ versus\
temperature and current observed in many experiments [1]. Correspondingly, in the time domain, the auto-correlation function of the resistance fluctuations displays a variety of behaviors (from a power-law up to an exponential decay) which are then finely tuned by the external conditions. \
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{\\bf References} \
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{\\bf 1.} M. B. Weissman, {\\em Rev. Mod. Phys.}, {\\bf 60}, 537, (1988).\
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{\\bf 2.} C. Pennetta, in {\\em Noise and Stochastics in Complex Systems \
and Finance}, ed. by\
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J. Kert\\'esz, S. Bornholdt, R. Mantegna, Procs. of SPIE, \
6601, 66010K (2007).\
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{\\bf 3.} C. Pennetta, E. Alfinito and L. Reggiani,\
Procs. 19-th ICNF Conf., ed. by\
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M. Tacano, Y. Yamamoto, M. Nakao, \
AIP Procs. No. 2007930186, 431 (2007).\
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