32 resultados para Titania-supported platinum


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We investigate the mobility of nonlinear localized modes in a generalized discrete Ginzburg-Landau-type model, describing a one-dimensional waveguide array in an active Kerr medium with intrinsic, saturable gain and damping. It is shown that exponentially localized, traveling discrete dissipative breather-solitons may exist as stable attractors supported only by intrinsic properties of the medium, i.e., in the absence of any external field or symmetry-breaking perturbations. Through an interplay by the gain and damping effects, the moving soliton may overcome the Peierls-Nabarro barrier, present in the corresponding conservative system, by self-induced time-periodic oscillations of its power (norm) and energy (Hamiltonian), yielding exponential decays to zero with different rates in the forward and backward directions. In certain parameter windows, bistability appears between fast modes with small oscillations and slower, large-oscillation modes. The velocities and the oscillation periods are typically related by lattice commensurability and exhibit period-doubling bifurcations to chaotically "walking" modes under parameter variations. If the model is augmented by intersite Kerr nonlinearity, thereby reducing the Peierls-Nabarro barrier of the conservative system, the existence regime for moving solitons increases considerably, and a richer scenario appears including Hopf bifurcations to incommensurately moving solutions and phase-locking intervals. Stable moving breathers also survive in the presence of weak disorder. © 2014 American Physical Society.

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The chapter discusses both the complementary factors and contradictions of adopting ERP based systems with enterprise 2.0. ERP is characterized as achieving efficient business performance by enabling a standardized business process design, but at a cost of flexibility in operations. It is claimed that enterprise 2.0 can support flexible business process management and so incorporate informal and less structured interactions. A traditional view however is that efficiency and flexibility objectives are incompatible as they are different business objectives which are pursued separately in different organizational environments. Thus an ERP system with a primary objective of improving efficiency and an enterprise 2.0 system with a primary aim of improving flexibility may represent a contradiction and lead to a high risk of failure if adopted simultaneously. This chapter will use case study analysis to investigate the use of a combination of ERP and enterprise 2.0 in a single enterprise with the aim of improving both efficiency and flexibility in operations. The chapter provides an in-depth analysis of the combination of ERP with enterprise 2.0 based on social-technical information systems management theory. The chapter also provides a summary of the benefits of the combination of ERP systems and enterprise 2.0 and how they could contribute to the development of a new generation of business management that combines both formal and informal mechanisms. For example, the multiple-sites or informal communities of an enterprise could collaborate efficiently with a common platform with a certain level of standardization but also have the flexibility in order to provide an agile reaction to internal and external events.