811 research outputs found
On the Analysis of Evolutionary Algorithms
There is a lot of experimental evidence that crossover is, for some functions, an essential operator of evolutionary algorithms. Nevertheless, it was an open problem to prove for some function that an evolutionary algorithm using crossover is essentially more efficient than evolutionary algorithms without crossover. In this paper, such an example is presented and its properties are proved
On the Choice of the Mutation Probability for the (1+1) EA
When evolutionary algorithms are used for function optimization, they perform a heuristic search that is in fluenced by many parameters. Here,the choice of the mutation probability is investigated. It is shown for a non-trivial example function that the most recommended choice for the mutation probability 1 / n is by far not optimal,i.e., it leads to a superpolynomial running time while another choice of the mutation probability leads to a search algorithm with expected polynomial running time. Furthermore, a simple evolutionary algorithm with an extremely simple dynamic mutation probability scheme is suggested to overcome the difficulty of finding a proper setting for the mutation probability
Realisierung und Überprüfung eines 3D-Tastsystems für Mikro-Bauteile
Es wird ein neues 3D-Tastsystem vorgestellt, dessen Design nicht nur bezüglich isotroper Steifigkeit am Tastelement, sondern auch bezüglich wirtschaftlicher Herstellung der einzelnen Bauteile und deren einfacher Montage optimiert ist. Eine Verlagerung des Tastelementes resultiert in einer Änderung der Position und/oder Orientierung einer beweglich gelagerten Messplatte, in welche der Taststift geschraubt wird. Die Bewegungen der beweglichen Messplatte werden mit kapazitiven Sensoren gemessen. Die Geometrie des Tastsystems wird unter Verwendung der Finite-Elemente-Methode (FEM) berechnet und mittels Kraft-Messungen überprüft. Damit steht ein verifiziertes Werkzeug zur Verfügung, mit welchem die Eigenschaften des Tastsystems, beispielsweise dessen Steifigkeiten, an vorgegebene Spezifikationen angepasst werden können. So werden verschiedene Varianten des Tastsystems vorgestellt, die für einen Einsatz auf (Mikro-) Koordinatenmessgeräten oder Werkzeugmaschinen angepasst sind. Die geometrische Überprüfung des Tastsystems umfasst die Bestimmung des Linearitätsfehlers in Antastrichtung, die maximale Antastabweichung, die Wiederholgenauigkeit sowie den Einfluss der Umgebungsbedingunge
Depolarization nearfield scanning optical microscopy: influence of wavelength and tip-shape on the lateral resolution
CeCar: A platform for research, development and education on autonomous and cooperative driving
International audienceIn this paper, we introduce CeCar as an affordable model-car based platform supporting research, development and education in the field of autonomous and cooperative driving. We present the application-oriented use cases and key platform requirements , and explain the logical and technical architecture of the CeCar platform, alongside with details on the underlying mod-ularity concept. Subsequently, we introduce CeCar application scenarios for the areas research, development and education, and provide relevant application examples. Further, we discuss the CeCar platform concept in comparison with other model-car based education and research platforms, and outline planned future work on the CeCar platform
High temperature critical O(N) field models by LCE series
The critical properties of renormalizable O(N) field models are determined by
means of the high order () behaviour of convergent linked cluster
series on finite temperature lattices. It is shown that those models become
weakly coupled at the phase transition. The critical exponents agree to those
of the corresponding superrenormalizable 3-dimensional models. Concerning
critical amplitudes and subcritical behaviour, corrections induced by
renormalizable couplings are measurable.Comment: 10 pages, late
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