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Consideration of the influence of manufacturing tolerances in the design process of electrical machines using the example of a permanent magnet synchronous machine
Get PDFThe production process of electrical machines is subject to manufacturing and material tolerances. These tolerances have an influence on both, the mean torque and the torque ripple. Consequently, they exert an active influence on the speed-torque map (operating points), as well as the equivalent circuit diagram parameters for a permanent magnet synchronous machine, and the operational behavior (efficiency, noise development) of the electrical machine. In addition to striving lower costs, there is a growing emphasis on achieving higher energy efficiency. Thus, an accurate prediction of machine parameters is still essential during the early development process, despite manufacturing-related deviations.
In this study, the prediction of machine parameters is demonstrated using the example of a PMSM
Diffusion-based Visual Counterfactual Explanations - Towards Systematic Quantitative Evaluation
No full textLatest methods for visual counterfactual explanations (VCE) harness the power of deep generative models to synthesize new examples of high-dimensional images of impressive quality. However, it is currently difficult to compare the performance of these VCE methods as the evaluation procedures largely vary and often boil down to visual inspection of individual examples and small scale user studies. In this work, we propose a framework for systematic, quantitative evaluation of the VCE methods and a minimal set of metrics to be used. We use this framework to explore the effects of certain crucial design choices in the latest diffusion-based generative models for VCEs of natural image classification (ImageNet). We conduct a battery of ablation-like experiments, generating thousands of VCEs for a suite of classifiers of various complexity, accuracy and robustness. Our findings suggest multiple directions for future advancements and improvements of VCE methods. By sharing our methodology and our approach to tackle the computational challenges of such a study on a limited hardware setup (including the complete code base), we offer a valuable guidance for researchers in the field fostering consistency and transparency in the assessment of counterfactual explanations
Systematic methods for the synthesis of equidistant MIMO arrays
No full textFinding a feasible antenna arrangement for multiple input multiple output (MIMO) arrays to serve a specific purpose is a first crucial step towards a successful MIMO radar system design. Design methods to synthesize uniformly weighted and equidistant MIMO arrays are proposed and investigated. The methods can be used to gain a design foundation for 1D or 2D arrays without software tools or programming effort. Since the presented approach does not consider electromagnetic fields, electromagnetic full-wave simulations might be required additionally. The method is based on sequentially copying and displacing antenna groups with the help of a number scheme. A nomenclature is proposed to classify the degrees of freedom in the design procedure. If the antennas are aligned to a uniform grid, a polynomial representation of the array can be chosen alternatively. This method is beneficial when redundancies of a produced array and where they appear must be analyzed. A new design problem arises when an array is to consist of only transceiving antennas, which can be analyzed with polynomial multiplication. One strategy to find a suitable MIMO array consisting of transceiver elements is given and evaluated
Investigation of an inline inspection method for the examination of cylinder-like specular surfaces using deflectometry
Get PDFAn optical measuring method is presented, with which it is possible to measure and evaluate reflective cylindrical surfaces using a combination of deflectometry and subsequent reconstruction of the surface. The system is set up and tested on rolling elements of cylindrical roller bearings. However, it is not limited to this use case and can be applied to other cylindrical specular surfaces. The system distinguishes itself from existing test methods through the combination of high-resolution three-dimensional defect measurement with a very short recording time, and offers the possibility of introducing tolerance limits in the production of cylindrical specular surfaces. With this method, it is possible to record a defect with the dimensions of 1.3 mm by 1.8 mm within 5 s and to reconstruct the absolute depth. The resolution of the system is below 10 μm in both X- and Y-direction, and is therefore sufficiently accurate to detect typical surface defects such as scratches, dents, or deformations. To validate the measured values of the system, the results of an artificially generated 10.35 μm deep defect location were compared with those of a highly accurate mechanical stylus measurement
Automatic Extraction of Buildings Boundaries Using Satellite Imagery with High Spatial Resolution and Deep Learning Methods
No full textSoziale Kategorisierung und soziale Diskriminierung bei Exklusion versus Inklusion der eigenen Person
No full textProposes a theoretical model of antecedents of the salience of social categorizations that is strongly related to the work of J. S. Bruner (1957) and P. J. Oakes (1987). In addition, the results of an empirical study using college students are presented which examined several hypotheses derived from the model. First, it was investigated whether exclusion vs inclusion of the perceiver with respect to a social categorizations affected the salience of this classification. Second, the study examined the relationship between social categorization on the one hand and social discrimination on the other. The results show that under otherwise equal conditions an inclusive social categorization is more salient than an exclusive one. In addition, in line with self-categorization theory, a significant correlation between the salience of a social categorization and tendencies toward ingroup favoritism appeared only for Ss strongly identified with the salient self-category, but not for low identifiers. The results of the present study are interpreted as a support of the proposed model of the salience of social categorizations
