Sökning: "non-linear optical"
Visar resultat 21 - 25 av 60 avhandlingar innehållade orden non-linear optical.
21. Stability and Mobility of Localized and Extended Excitations in Nonlinear Schrödinger Models
Sammanfattning : This thesis is mainly concerned with the properties of some discrete nonlinear Schrödinger equations. These naturally arise in many different physical contexts as the limiting form of general dynamical lattice equations that incorporate nonlinearity and coupling. LÄS MER
22. Differential railway track settlement in a transition zone – Field measurements and numerical simulations
Sammanfattning : In a transition zone between two different railway track forms, there is a discontinuity in track structure leading to a gradient in track stiffness. Examples include transitions between different superstructures, e.g., slab track to ballasted track, and/or between different substructures, e. LÄS MER
23. Nonlinear materials for optical power limiting : characterization and modelling
Sammanfattning : High power laser pulses can be a threat to optical sensors, including the human eye. Traditionally this threat has been alleviated by colour filters that block radiation in chosen wavelength ranges. LÄS MER
24. Phase Modulation Techniques for On-Off Keying in Optical Fibre Transmission
Sammanfattning : Increasing the channel bit rate is an efficient way to upgrade traffic capacity in installed transmission links. At bit rates of the order of 40 Gb/s, on-off keying (OOK) transmission becomes severely impaired by non-linear effects especially Intra-channel Four-Wave Mixing (IFWM) which limit the power at which the signal can be transmitted, and ultimately the transmission distance. LÄS MER
25. The alternate-phase return-to-zero modulation format in high-speed optical-fibre communications
Sammanfattning : Increasing the channel bit rate is an efficient way to upgrade traffic capacity in installed transmission links. At bit rates of the order of 40 Gb/s, on-off keying transmission becomes severely impaired by non-linear effects,particularly Intra-channel Cross-Phase Modulation (IXPM) and Intra-channel Four-Wave Mixing (IFWM), which cause pulses in different bit slots to interact with each-other. LÄS MER