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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.
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.
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.
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   
15.
《自动化信息》2008,(9):63-65
首秦4300mm宽厚板轧机自动化系统是一个装备水平和自动化程度较高的先进系统。文中详细描述了该轧机自动化系统的特点、系统分级和硬件构成、控制功能及软件系统,最后介绍了现场调试中遇到的问题和解决方案。  相似文献   
16.
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   
18.
研究了≤0.005%C-2.5%-2.8%Si的2.5mm热轧电工钢板在850—1100℃常化对0.5mm冷轧板880℃+950℃退火后组织和磁性能的影响。结果表明,热轧板常化温度升高,冷轧板退火后的再结晶晶粒增大,铁损降低,磁感呈单调递增趋势;热轧板常化温度超过1000℃,因第2相固溶而后弥散析出,退火冷轧晶粒细化,铁损增加,因此该钢热轧板最佳常化温度为1000℃。  相似文献   
19.
分析了国内外热轧板带的板形检测技术及几种板形检测方法的发展应用状况,并就热轧板带产 品的发展及要求展望了未来板形检测的发展方向。  相似文献   
20.
汽车牌照自动识别系统在智能交通系统(ITS)中占据重要地位,有着广阔的发展前景,本文介绍了汽车牌照识别系统,该系统包括了牌照的抓拍、牌照定位,识别等内容,最后给出了现场实验结果。  相似文献   
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