In this paper, we mainly focus on two issues (1) SVM is very sensitive to noise. (2) The solution of SVM does not take into consideration of the intrinsic structure and the discriminant information of the data. To address these two problems, we first propose an integration model to integrate both the local manifold structure and the local discriminant information into ?1 graph embedding. Then we add the integration model into the objection function of υ-support vector machine. Therefore, a discriminant sparse neighborhood preserving embedding υ-support vector machine (υ-DSNPESVM) method is proposed. The theoretical analysis demonstrates that υ-DSNPESVM is a reasonable maximum margin classifier and can obtain a very lower generalization error upper bound by minimizing the integration model and the upper bound of margin error. Moreover, in the nonlinear case, we construct the kernel sparse representation-based ?1 graph for υ-DSNPESVM, which is more conducive to improve the classification accuracy than ?1 graph constructed in the original space. Experimental results on real datasets show the effectiveness of the proposed υ-DSNPESVM method. 相似文献
In this work, we study numerically the thinning of a perfectly conducting, slightly viscoelastic liquid jet under a radial electric field by using a one-dimensional model. In the presence of the electric field, the viscoelastic jet develops into a stable beads-on-a-string structure with a uniform thickness filament as in the non-electrified case, but the \( 1/3De \) (De: the Deborah number) exponential law of filament thinning and polymer stress growth holds no more. The electric field decelerates the thinning of the jet and induces periodic oscillations of the flow properties. The balance between the surface tension, viscoelastic stress and electrostatic force is absent in the filament, and as a result, the extensional flow there becomes unsteady. 相似文献
This paper proposes a new ITPS panel with special corrugated-core webs which are designed with cutouts for weight saving. The structural design problem was formulated with mass per unit area of the ITPS as the objective function and some functional requirements as constraints. We developed the optimizer fulfilling both thermal and structural functions for minimal areal density. The optimization problem was solved by interpolating the residual error of response surface approximation (RSA) with Radial Basis Function (RBF) to establish the improved RSA (IRSA). The 400 preliminary design points were obtained using Latin Hypercube Sampling method. The quadratic polynomial RSA of the ITPS sandwich panel performance was generated by the least squares method (LSM) based on finite element results and IRSA was used to optimize the constraints. Transient heat transfer, stress and buckling analyses were conducted using finite element method (FEM). Finally, a new ITPS panel with optimal dimensions was obtained. The optimization results show that the areal density of the new ITPS panel decreases by 26.27 % compared with the previous research, which proves the potential of this new design optimization method for the future spacecraft vehicles. 相似文献
Optimization for structural crashworthiness and energy absorption has become an important topic of research attributable to its proven benefits to public safety and social economy. This paper provides a comprehensive review of the important studies on design optimization for structural crashworthiness and energy absorption. First, the design criteria used in crashworthiness and energy absorption are reviewed and the surrogate modeling to evaluate these criteria is discussed. Second, multiobjective optimization, optimization under uncertainties and topology optimization are reviewed from concepts, algorithms to applications in relation to crashworthiness. Third, the crashworthy structures are summarized, from generically novel structural configurations to industrial applications. Finally, some conclusions and recommendations are provided to enable academia and industry to become more aware of the available capabilities and recent developments in design optimization for structural crashworthiness and energy absorption.
Structural and Multidisciplinary Optimization - Light weight and crashworthiness signify two main challenges facing in vehicle industry, which often conflict with each other. In order to achieve... 相似文献