In this paper, we address the affine template matching of general images. The extensive search space of affine transformations necessitates effective searches of the global optimum. The proposed method utilizes differential evolution (DE), which is a method of metaheuristic optimization, to achieve that goal. Self-adaptive DEs can be useful and are applicable in a wide range of studies as they tune crossover rate and scaling factor (F) themselves over generation iteration. However, this approach is not particularly good for affine template matching because the population often converges to local optima. In order to solve this problem, the population is divided into two equal groups for exploitation and exploration. The former group utilizes current-to-best/1, and the latter group adopts improved current-to-rand/1 for the mutation scheme. Furthermore, the proportion of the population sizes of the two groups are linearly changed on the basis of the best sum of absolute difference error measurements over each generation. These ideas are easy and simple, but experimental results have revealed our method to be more accurate than the state-of-the-art method.
Measurements of magnetic susceptibility, thermal expansion and electrical resistivity were carried out at temperatures ranging from 77 K to room temperature on a polycrystalline sample of the antiferromagnetic compound MnSe with rock salt structure. The curves obtained show a large thermal hysteresis and a sharp transition at the Néel temperature. The change in the susceptibility at TN (197 K) as the sample is cooled is -2.2×10-5 emu/g. The value of exchange striction is estimated to be 2.0. The change in the thermal expansion at TN is -5.6×10-4. The exchange striction and the first-order transition due to it cause the anomalous magnetic, crystalline and electrical behaviors at TN in MnSe.
This paper presents an evolutional compensator design for motion control systems using Genetic Algorithms ( G A ) . The control system is composed of a robust 2-Degrees-Of-Freedom (2DOF) compensator based on the coprime factorization description. A feedback compensator in the 2DOF control system is mainly designed under the p-Synthesis framework to ensure the robust stability because the real plant mechanism includes structured uncertainties, e.g., the frequency perturbations of vibration modes. I n addition, a feedforward compensator is optimized by G A paying attention to the robust servo characteristics against the mechanical parameter variations, where the structuring and parameterization of the compensator can be autonomously achieved to satisfy the desired servo characteristic with the resonant vibration suppression performance. The effectiveness of the proposed controller design has been verified by experiments using a prototype.
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