渗流问题的拓扑优化

分析拓扑优化中的密度惩罚函数插值法SIMP（Solid isotropic material with penalization model）,将结构力学中的拓扑优化方法应用到渗流问题的拓扑优化设计中,用有限元的方法建立了简单的理想状态下的渗流问题的拓扑优化数学模型,并采用基于剃度法的数值解法-优化准则法（OC系列算法）,以设计具有最小能量损耗情况下的流体最佳流动路径的拓扑分布。以一组二维渗流问题为例,说明了该模型的有效性,为渗流问题的优化设计提供了一种有效的新思路和方法。     

核电站放射性废物超压机压饼装载优化研究

从放射性废物最小化角度出发, 将某核电站放射性废物压饼的装载过程简化成装箱问题进行研究, 结合降序最佳适应算法提出了压饼装载优化方案, 并进行模拟运算。结果证明优化方案能明显提高再包装桶的装载率, 同时从压饼存放、转运以及装载效率等方面进行了对比分析, 证明了该优化方案具有可行性。     

Development of the FUMILI minimization package

The suggested FUMILI package development has the following advantages: a more convenient and friendly user interface; no limit on the number of parameters and experimental points; speed advantage when the number of parameters is high enough; there are options to ignore wrong experimental points and correct experimental errors. The preliminary scan is envisaged for complicated tasks.     

From 2D to 2.5D i.e. from painting to tactile model

Commonly used to produce the visual effect of full 3D scene on reduced depth supports, bas relief can be successfully employed to help blind people to access inherently bi-dimensional works of art. Despite a number of methods have been proposed dealing with the issue of recovering 3D or 2.5D surfaces from single images, only a few of them explicitly address the recovery problem from paintings and, more specifically, the needs of visually impaired and blind people.The main aim of the present paper is to provide a systematic method for the semi-automatic generation of 2.5D models from paintings. Consequently, a number of ad hoc procedures are used to solve most of the typical problems arising when dealing with artistic representation of a scene. Feedbacks provided by a panel of end-users demonstrated the effectiveness of the method in providing models reproducing, using a tactile language, works of art otherwise completely inaccessible.     

G1 Hierarchical Bézier Surface over Arbitrary Meshes

This paper presents a method for constructing composite surfaces based on a collection of quadrilateral patches. A global parameterization using bilinear quadrilateral meshes and FEM like minimization procedure are introduced. Smoothing conditions such as C¹ and G¹ are handled by constraint equation and a related duality argument is implemented. The surfaces that can be constructed in this way include conforming and non-conforming connections (3 n 6, T-nodes) between elementary patches. Non-manifold surfaces are automatically treated also by this data structure. The underlying quadratic programming with linear constraints is solved by duality methods. Hierarchical data structure with bordering matrices methods are implemented to deal with local refinement (subdivision). The present work details the actual implementation for the case of Bézier patches.     

基于多重假设的视频压缩感知分层重建

为了改进视频压缩感知方案的性能,提出了一种基于多重假设的视频压缩感知分层重建方案。该重建方案以图像组为单位进行,首先独立重建关键帧,接下来对图像组中的每个非关键帧分配重建层级,并按照层级顺序由低至高逐层重建。每个非关键帧的重建过程逐块进行,需要其时域参考帧及当前帧中的空域数据集为每个重建块做混合多重假设预测,并通过求解全变分最小化问题重建预测残差,最后将预测值与预测残差相加得到重建图像。实验结果表明,在相同采样率下,本文提出的基于多重假设的分层重建方案比已有的方法可以获得最高约3.2dB的峰值信噪比增益。     

On the order of test goals in specification-based testing

Model-based testing techniques often select test cases according to test goals such as coverage criteria or mutation adequacy. Complex criteria and large models lead to large test suites, and a test case created for one coverage item usually covers several other items as well. This can be problematic if testing is expensive and resources are limited. Therefore, test case generation can be optimized in order to avoid unnecessary test cases and minimize the test generation and execution costs. Because of this optimization the order in which test goals are selected is expected to have an impact on both the performance of the test case generation and the size of resulting test suites, although finding the optimal order is not feasible in general. In this paper we report on experiments to determine the effects of the order in which test goals are selected on performance and the size of resulting test suites, and evaluate different heuristics to select test goals such that the time required to generate test suites as well as their size are minimized. The test case generation approach used for experimentation uses model checkers, and experimentation shows that good results can be achieved with any random ordering, but some improvement is still possible with simple heuristics.     

大亚湾核电站放射性固体废物管理

本文系统地介绍了大亚湾核电站 (GNPS)放射性固体废物的管理体系和处理方法以及近 1 0年来的持续改进。由于重视并在实践中努力实施废物最少化原则 ,从废物的源头控制、处理工艺、测量估算技术和监督管理等方面不断改进 ,大亚湾核电站自 1 994年投产以来 ,放射性固体废物产生量连年下降 ,2 0 0 2年每台机组减少到 63 .5m3,约为 1 995年 1 2 7m3的 5 0 % ,达到法国同类核电机组的先进水平 ;从1 994至 2 0 0 2年的 9年间两台机组累计的放射性固体废物产生量为 1 5 63 .5 1m3,仅为设计值的 1 8% ,废物货包符合安全处置的标准和要求。另外 ,本文还就进一步减少废物产生量的一些新工艺进行了分析 ,提出了建议     

Multiobjective design and control optimization for minimum thermal postbuckling dynamic response and maximum buckling temperature of composite laminates

Design and control optimization is presented to minimize the thermal postbuckling dynamic response and to maximize the buckling temperature level of composite laminated plates subjected to thermal distribution varying linearly through the thickness and arbitrarily with respect to the in-plane coordinates. The total elastic energy of the laminates is taken as a measure of the dynamic response. The optimization control problem is solved under constraints on the laminate thickness and the control energy produced by a transverse dynamic load distributed over the upper surface of the laminate. The constrained control objective is expressed as the sum of the total elastic energy and penalty term involving the control force, which may be considered as a measure of the control energy. The thickness of layers and the fibers orientation angles are taken as optimization design variables. The design and control objectives are formulated based on shear deformation theory accounting for the von-Karman nonlinearity. The displacements are chosen as the sum of time-independent displacements due to the static thermal load and time-dependent displacements due to the initial disturbances and the applied control force. Liapunov–Bellman theory is used to obtain the optimal control force, buckled deflections and controlled elastic energy. Numerical examples are presented for angle-ply antisymmetric laminates with simply supported edges. Graphical studies are carried out to show the advantages of the present design and control procedures.