IP networks have established as a global telecommunication platform with increasing user population and an extending spectrum of services. The traffic is also steadily increasing, recently driven by peer to peer networking in addition to client server based applications. Network planers and operators have to ensure the scalability of IP platforms in a permanent upgrade process for transmission capacities. At present, Deutsche Telekom and other telecommunication network providers are introducing traffic engineering methods to achieve an optimum resource utilization.In a first step, traffic engineering can be applied to a predefined network topology, but a comprehensive approach has to be coordinated with a process for upgrading the link capacities and has to prepare for relevant failure scenarios. We have evaluated the efficiency of traffic engineering together with simple link upgrade strategies in order to get a maximum throughput. Therefore a predefined traffic matrix T is taken into account. The optimization goal is to scale the traffic matrix by a maximum factor λ max such that the traffic demand λ max T can still be carried on the available network resources. The influence of the network topology on the evaluation results is shown in examples with regard to single link failures.
The basic idea of this paper is developing process models which are online capable, i.e. which combine data from online measurements and simplified plastomechanical interrelations for the forecast of equivalent strain, equivalent strain rate and the temperature in the core of the part being forged. These models deliver the numerical basis for the forecast of the microstructures obtained. In combination with optimization methods a numerical assistant for the forging press operator can be implemented.
At the Institute of Metal Forming of the RWTH Aachen University, models for the core fibre of a forged block were developed. The development of the models was based on reference solutions which were derived from FEM‐calculations. The equivalent strain and equivalent strain rate are thereby determined by the change of the geometry of the workpiece (i.e. change in length or change in height). For the determination of the temperature distribution along the core fibre an explicit Finite Difference model is used. This model considers the loss of temperature at the surface due to radiation and convection, and also the dissipation in the core fibre. For the subsequent prediction of the microstructure the module STRUCSIM, which was developed at the Institute of Metal Forming, is used. The results of the models show good agreements with the FEM‐solutions.
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