Stephan Pachnicke Livres

The thesis explores the advancements in next-generation optical communication systems, emphasizing the importance of high data rates, signal powers, and dense wavelength division multiplexing (DWDM). It discusses the evolution of automatically switched transport networks (ASTN) that facilitate transparent optical paths without signal conversion. The work highlights the critical impact of physical impairments, such as dispersion and noise, on signal quality. A swift evaluation of signal quality over transmission distances is essential for optimizing path selection in complex, meshed networks.

Focusing on the significance of Bragg gratings, this master's thesis explores their critical role in optical communications. The work, distinguished for its academic excellence, delves into the principles and applications of these devices, highlighting their impact on advancing technology in the field of electrotechnology. Through a comprehensive analysis, the thesis contributes valuable insights into the functionality and potential of Bragg gratings, making it a noteworthy resource for scholars and practitioners alike.

Next generation optical communication systems will have to transport a significantly increased data volume at a reduced cost per transmitted bit. To achieve these ambitious goals optimum design is crucial in combination with dynamic adaptation to actual traffic demands and improved energy efficiency. In the first part of the book the author elaborates on the design of optical transmission systems. Several methods for efficient numerical simulation are presented ranging from meta-model based optimization to parallelization techniques for solving the nonlinear Schrödinger equation. Furthermore, fast analytical and semi-analytical models are described to estimate the various degradation effects occurring on the transmission line. In the second part of the book operational aspects of optical networks are investigated. Physical layer impairment-aware routing and regenerator placement are studied. Finally, it is analyzed how the energy efficiency of a multi-layer optical core network can be increased by dynamic adaptation to traffic patterns changing in the course of the day.

Die Arbeit thematisiert die zentrale Bedeutung des Transportwesens und der logistischen Planung im betriebswirtschaftlichen Kontext, insbesondere die Tourenplanung. Diese umfasst verschiedene Planungsprobleme, wie die effiziente Belieferung von Kunden aus Lagern unter Berücksichtigung begrenzter Fahrzeugkapazitäten und vorgegebener Zeitfenster. Ein konkretes Beispiel ist die just-in-time Belieferung durch Paketdienste, die als vehicle routing problem with time windows (VRPTW) bekannt ist. Die Zielsetzung des VRPTW beinhaltet eine hierarchische Struktur, die zunächst die Fahrzeuganzahl und anschließend die Minimierung der Gesamtdistanz fokussiert.