Structural topology optimization using ant colony optimization algorithm

The ant colony optimization (ACO) algorithm, a relatively recent bio-inspired approach to solve combinatorial optimization problems mimicking the behavior of real ant colonies, is applied to problems of continuum structural topology design. An overview of the ACO algorithm is first described. A discretized topology design representation and the method for mapping ant's trail into this representation are then detailed. Subsequently, a modified ACO algorithm with elitist ants, niche strategy and memory of multiple colonies is illustrated. Several well-studied examples from structural topology optimization problems of minimum weight and minimum compliance are used to demonstrate its efficiency and versatility. The results indicate the effectiveness of the proposed algorithm and its ability to find families of multi-modal optimal design.     

An efficient multiobjective differential evolution algorithm for engineering design

Solving engineering design and resources optimization via multiobjective evolutionary algorithms (MOEAs) has attracted much attention in the last few years. In this paper, an efficient multiobjective differential evolution algorithm is presented for engineering design. Our proposed approach adopts the orthogonal design method with quantization technique to generate the initial archive and evolutionary population. An archive (or secondary population) is employed to keep the nondominated solutions found and it is updated by a new relaxed form of Pareto dominance, called Pareto-adaptive ϵ-dominance (paϵ-dominance), at each generation. In addition, in order to guarantee to be the best performance produced, we propose a new hybrid selection mechanism to allow the archive solutions to take part in the generating process. To handle the constraints, a new constraint-handling method is employed, which does not need any parameters to be tuned for constraint handling. The proposed approach is tested on seven benchmark constrained problems to illustrate the capabilities of the algorithm in handling mathematically complex problems. Furthermore, four well-studied engineering design optimization problems are solved to illustrate the efficiency and applicability of the algorithm for multiobjective design optimization. Compared with Nondominated Sorting Genetic Algorithm II, one of the best MOEAs available at present, the results demonstrate that our approach is found to be statistically competitive. Moreover, the proposed approach is very efficient and is capable of yielding a wide spread of solutions with good coverage and convergence to true Pareto-optimal fronts.     

Topology optimization of structures with integral compliant mechanisms for mid-frequency response

The purpose of this paper is to present a method for developing new truss-like sandwich structures that exhibit desirable mid-frequency vibratory characteristics. Specifically, a genetic algorithm optimization routine is used to determine candidate small scale structural topologies, i.e. unit cells, that may be used in the design of larger scale periodic sandwich structures. This multi-scale procedure is demonstrated starting with several unit cell topology optimization examples. From these examples a specific optimal unit cell is selected for further investigation and integration into a periodic sandwich beam. Computational results indicate that the proposed optimization approach is effective when used to design new structures for reduced mid-frequency vibratory response.     

抗量子计算公钥密码需求分析与技术路线

本文对国外量子计算机研究进展情况进行了分析,并针对量子计算机对于信息安全的挑战,讨论了国内下一代公钥密码技术的需求、发展思路和技术路线。     

“可编程序控制器原理及其应用”课程试验教学软件的研制

本文在原有的TVT-90硬件和软件实验系统基础上,用组态软件实现"可编程序控制器原理及其应用"试验的动态模拟和仿真,在计算机上实现实验过程的动画仿真,使学生在实验过程中可以进行与生产过程的交互模拟,反复验证自己的程序设计过程是否正确,并且理解真实的生产装置的控制过程。     

以就业为导向的实训改革

本文通过在职业教育中引入"教学设计"理念和"以学生为主体、能力培养为本位"的教学思想,努力探索全方位培养学生的专业能力、社会能力、方法能力和道德情操的教学模式,特别是实训考核评价方法的创新,具有普适性和推广价值。     

塑造河流的性格——以郧西县城市河流生态景观规划为例

本文以郧西城市河流生态景观规划为例,论述了河流规划应突出其固有的个性特征,并通过河流驳岸的生态化改造和河流绿化规划,将生态与景观有效结合。     

街道景观规划与城市记忆研究

在街道景观规划中,对城市历史文化进行分析研究,力求做到开发与保护的平衡,延续城市所特有的文脉。并通过实例为街道景观规划作了一些尝试性研究。     

图像边缘检测在DM642上的应用研究

采用TMS320DM642EVM作为数字图像处理硬件平台,利用CCS开发环境来构建程序并对其进行优化;通过对改进后的Log算子和小波多尺度方法提取到的边缘图像进行数据融合,得到一幅新的边缘图像。实验结果表明,该方法提高了边缘检测的运算速度,满足了实时性要求;并能有效地抑制噪声的影响,保留了图像边缘细节。     

智能交通系统中的最短路径算法分析

智能交通涉及到交通领域的多个方面,如何寻找最短路径是其核心问题之一。文章着重讨论了智能交通系统功能实现中的关键技术一求解最短路径。对于国内外一些求解最短路径的经典算法的复杂度问题进行了分析。