Robust target functions in electromagnetic design

Uncertainties in the design variables of non-linear engineering optimization problems are often neglected. That could result in considerable deterioration of the target function value of an implemented design compared with the computed optimal solution. This effect can be reduced with robust optimization, where it is tried to achieve robust designs by actively embedding the uncertainties and robustness measures in the optimization process. A methodology for robust optimization of non-linear problems is presented, including practical methods for the solution of such programs. The benefits of the approach are discussed in a numerical field calculation example

Enhanced Identification of Hidden Conductive Objects with Deterministic and Stochastic Methods

The identification of conductive objects of known shape embedded in low- or non-conductive regions is a special application of non-destructive testing, with important applications in some surgical procedures. In particular, some classes of fractures are routinely stabilized and aligned by the use of intra-medullary nails. Identifying the position and the orientation of the drill holes hidden by bone and tissue is currently done by X-Ray with all the well known disadvantages of this technology. The idea of substituting this methodology with an eddy-current based one has been explored in previous work but the developed technique suffered from some hard to address shortcomings. In this paper we propose a new technique which is computationally efficient and inexpensive to implement

Numerical Simulation Framework for Weakly Coupled Multiphysical Problems in Electrical Engineering

Every engineering discipline faces the fact of ever-shortening time-to-market windows and development cycles. In order to counteract these, virtual prototyping, sim- ulation and problem optimization are employed in a rapidly increasing number of cases. Yet, the key to efficient problem formulation by professionals still lies in the use of sophisti- cated simulation software capable of processing numerous diverse design and optimization tasks in a versatile way. More often than not, different tools for different workflows need to be coordinated and interdepend on each others data in the design process chain. When toolchains need to be run multiple times, as it is typically the case in numerical optimization, the lineup overhead tends to be tedious to both man and machine. This paper describes different aspects concerning the design of a software and data frame- work which tackles the problem of lining up software tools that may be incoherent in terms of data exchange and control mode. The resulting system covers all parts of multiphysical simulation problems that may arise in electrical engineering and its adjoining disciplines as an application of the finite element method

Bilateral use of Active Middle Ear Implants: Speech Discrimination Results in Noise

Background: Binaural sound reception has advantages over unilateral perception, including better localization and sound quality as well as speech and tone reception in both quiet and noisy environments. Up to now, most active middle ear implant (AMEI) users have been unilaterally implanted, but patient demand for an implant on the other side is increasing.Material & Methods: Ten bilaterally-AMEI implanted native German-speaking adults were included in the study. The Oldenburg sentence test was used to measure speech reception thresholds in noise. The subject's signal-to-noise ratio (SNR) at a speech reception score of 50% was calculated for different noise conditions. SRT was measured as a function of noise condition (nc) and listening condition (lc) - for example, SRT (lc,nc), with nc from S0N0, S0N-90, or S0N90 and lc from left, right or both. For each noise condition, the squelch effect and the binaural summation effect was calculated.Results: Patients in this study demonstrated improvement with bilateral AMEIs compared to right or left AMEI only in all three tested listening conditions. Statistical significance was found in the S0N0 condition to favor usage of bilateral AMI versus either the right or left side only.Discussion: The benefits of binaural hearing are well known, also in normal-hearing individuals. In the future every bilateral implantation should be a part of the clinical routine. Bilateral implantation can help to reduce problems in background noise and restore directional hearing.Der Erstautor gibt keinen Interessenkonflikt an