Assessment of noise attenuating powertrain components

Forschung im Ingenieurwesen - Wind turbine noise used to be dominated by aerodynamic blade noise, effectively masking mechanical noise, originating from the drivetrain. Successful blade noise...     

Characterizing cerebral oxygen metabolism employing oxygen-17 MRI/MRS at high fields

This article provides a comprehensive overview of oxygen (¹⁷O) magnetic resonance spectroscopy and imaging, including the advantages and challenges offered by the different methods developed thus far. The physiological role and relevance of oxygen, and its participation in aerobic metabolism, are addressed to emphasize the importance of the investigations and the efforts related to these developments. Furthermore, a number of methods employed in the determination of the cerebral metabolic rate of oxygen in neural cells will be presented, focusing primarily on methodologies enabling absolute quantification.     

Simulating the emergence of norms in different scenarios

This paper deals with EMIL-S, a software tool box which was designed during the EMIL project for the simulation of processes during which norms emerged in an agent society. This tool box implements the cognitive architecture of normative agents which was designed during the EMIL project which is also discussed in other papers in this issue. This implementation is described in necessary detail, and two examples of its application to several different scenarios are given, namely a scenario in which persons involved in micro finance are simulated and learn how to sanction free riders and how to learn from these sanctions, and a scenario in which simulated persons move through a simulated airport where they more often than not have to wait in queues and learn how to behave properly in queues.     

Manufacturing of integrative membrane carriers by novel powder injection molding

Although offering distinctive economic benefits the mass fabrication of carrier devices incorporating membranes as quasi-monolithic devices reveals strong technological challenges. Powder injection molding would be an effective process for this purpose, however, manufacturing parts of considerable wall thickness variations and to meet strong precision demands remains problematic. To evaluate novel ways of process conducts as well as to determine influencing parameters a demonstrator design had been developed which enabled the generation of thin membranes by controlled piston movement. Suitable lay-out of the runner system had been determined with the help of simulation calculations. The combined injection + embossing process conduct enabled to reduce minimum membrane thickness to about a half. Investigation of parameter influence showed that embossing force and gap width before injection have an ameliorative effect on membrane quality whereas the embossing delay time had no significant impact.     

A New Stable Splitting for the Isentropic Euler Equations

In this work, we propose a new way of splitting the flux function of the isentropic compressible Euler equations at low Mach number into stiff and non-stiff parts. Following the IMEX methodology, the latter ones are treated explicitly, while the first ones are treated implicitly. The splitting is based on the incompressible limit solution, which we call reference solution. An analysis concerning the asymptotic consistency and numerical results demonstrate the advantages of this splitting.     

Take care of your belongings today – securing accessibility to complex electronic business processes

Most of today’s business processes are based solely on digital data. Input, output, and intermediate results are pure digital objects. Keeping such data accessible and meaningful but even more importantly keeping the business processes functional is challenging. With regards to complex electronic business processes traditional archiving does not provide satisfactory results. Due to the fast technical life-cycle the time gap between archiving and re-enactment or reuse of a process poses risks and increases the uncertainty on achievable results. We propose a novel strategy bridging this specific time gap. For this we present a scalable and cost-effective infrastructure with associated workflows focusing on a process’ execution context. Most importantly the process’ developers are able to assess the preserved results in a timely manner, and thus, reduce the uncertainty on future re-enactment results.