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11.
On topology optimization of linear and nonlinear plate problems 总被引:1,自引:0,他引:1
In this paper we propose a new restriction method based on employing C
0-continuous fields of density defined on a set of meshes different from the one used for the finite element analysis. The
optimization procedure starts with using a coarse density-mesh compared to the finite element one. Once the convergence is
obtained in the optimization steps, a finer density-mesh is nominated for the further steps. Linear and nonlinear plate behaviors
are considered and formulated by Kirchhoff or Mindlin–Reissner hypothesis. Comparison is made with element/nodal based approaches
using filter. The results show excellent and robust performance of the proposed method. 相似文献
12.
Operator context scanning to support high segmentation rates for real time license plate recognition
Ioannis Giannoukos Author Vitae Christos-Nikolaos Anagnostopoulos Author VitaeAuthor Vitae Eleftherios Kayafas Author Vitae 《Pattern recognition》2010,43(11):3866-3878
Introducing high definition videos and images in object recognition has provided new possibilities in the field of intelligent image processing and pattern recognition. However, due to the large amount of information that needs to be processed, the computational costs are high, making the HD systems slow. To this end, a novel algorithm applied to sliding window analysis, namely Operator Context Scanning (OCS), is proposed and tested on the license plate detection module of a License Plate Recognition (LPR) system. In the LPR system, the OCS algorithm is applied on the Sliding Concentric Windows pixel operator and has been found to improve the LPR system’s performance in terms of speed by rapidly scanning input images focusing only on regions of interest, while at the same time it does not reduce the system effectiveness. Additionally, a novel characteristic is presented, namely, the context of the image based on a sliding windows operator. This characteristic helps to quickly categorize the environmental conditions upon which the input image was taken. The algorithm is tested on a data set that includes images of various resolutions, acquired under a variety of environmental conditions. 相似文献
13.
?smail Dinçer 《Advances in Engineering Software》2011,42(4):160-171
Determination of deformation modulus and coefficient of subgrade reaction of soils have major importance, whether the projects are in design, and construction or compaction assessment stage of earth filling structures. Plate load test is one of the frequently used method to directly determine the parameters but the method is both costly and time consuming. For this reason, this paper is concerned with the applications of artificial neural networks (ANN) and simple-multiple regression analysis to predict deformation modulus and coefficient of subgrade reaction of compacted soils from compaction parameters (such as maximum dry density (MDD) and optimum moisture content (OMC), field dry density (FDD), and field moisture content (FMC)). Regression analysis and artificial neural network estimation indicated that there are acceptable correlations between deformation modulus and coefficient of subgrade reaction and these parameters. Artificial neural networks model exhibits higher performance than traditional statistical model for predicting deformation modulus and coefficient of subgrade reaction. 相似文献
14.
齐滨 《自动化与仪器仪表》2011,(2):79-79,83
提出了中厚板轧机轧制力计算模型,并在此基础上,对数学模型进行在线自适应,使计算得到的轧制力更接近于实测值。 相似文献
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The authors develop an eigth-order model for bending of transversally isotropic plates and use integral transforms and a collocation
method to form a line-spring model for a cracked plate. The eigth-order model allows satisfaction of the three standard plate
bending boundary conditions; the normal moment, twisting moment, and transverse shear force, and an additional shear stress
resultant that allows analysis of transverse normal stresses near the crack tip. The line-spring model is used to develop
geometry correction factors for bending of finite-thickness plates, accounting for transverse shear deformation and pressurization
of the plate near the crack tip. The line-spring model is then applied to the problem of a plate with a reinforced crack,
and the results are used to validate an interpolation solution based on an energy method. While not explicitly analysed, the
models are applicable to many problems, including bending of bonded repairs, fracture and fatigue of composite and layered
materials, surface cracks, crack tip plasticity and crack closure or crack face interaction. 相似文献
17.
In this paper, the degenerate scale for plate problem is studied. For the continuous model, we use the null-field integral
equation, Fourier series and the series expansion in terms of degenerate kernel for fundamental solutions to examine the solvability
of BIEM for circular thin plates. Any two of the four boundary integral equations in the plate formulation may be chosen.
For the discrete model, the circulant is employed to determine the rank deficiency of the influence matrix. Both approaches,
continuous and discrete models, lead to the same result of degenerate scale. We study the nonunique solution analytically
for the circular plate and find degenerate scales. The similar properties of solvability condition between the membrane (Laplace)
and plate (biharmonic) problems are also examined. The number of degenerate scales for the six boundary integral formulations
is also determined.
Tel.: 886-2-2462-2192-ext. 6140 or 6177 相似文献
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