基于机群系统的大规模并行搜索算法--大型离散偏微分方程组快速求解

大量的科学与工程应用中,会经常遇到复杂偏微分方程组的求解问题,这些偏微分方程组一般无法得到分析解,实际采用的是将其离散后通过数值逼近方法来求得近似解.为了得到较高的求解精度,需要将离散网格划分得足够细,但是这样就成倍地增加了计算量,许多问题就是因为计算量过大而无法求解或不得不降低精度求解.本文在机群计算平台上,针对机群计算的特点,提出了一种大规模并行搜索算法,这种算法由于可以充分发挥各个结点的计算能力,有效降低结点之间的通信,因而具有很高的效率.文中对这一算法进行了详细描述.该算法已经成功地用于压力铸造过程的流场模拟计算之中,可以有效地解决一大类大型离散偏微分方程组的求解问题.对于同样规模的一个实际问题,并行算法的求解时间相对于串行算法,从3到4天下降到3个小时,取得了很好的并行加速.     

一种改进的正则图象

把正则图象的误差分成两部分：一部分为逼近误差，它是和原图象相关的确定型误差，另一部分为噪声传递误差，它是和噪声相关的随机型误差．通过正则图象代替原图象，求得逼近误差的近似值，然后将逼近误差近似值补给正则解，得到改进型正则解．对正则解以及逼近误差的计算，提出了快速算法，并有严密的理论推导．实验结果表明改进型正则图象的恢复效果优于传统正则解．在一敷的正则化方法中，可以借鉴本文提到的方法改进正则解．     

多层轻钢结构住宅体系设计

针对多层轻钢结构住宅的结构体系 ,提出了结构体系的建立方法、分析了主要构件及节点设计原理和基本的技术要求。研究了轻钢结构住宅体系的设计以及推广意义     

重载轻型桁架斜拉式组合挂篮的研究

主要介绍了重载轻型桁架斜拉式组合挂篮的结构形式、特点，分析了其计算模型，并通过工程算例的验证，表明了该种挂篮结构合理、构思独特．与其它结构形式的挂篮相比，它受力较为均匀、节省材料、减轻自重，是一种较为理想的新型挂篮结构，有实际应用价值．     

Energy-based robust controller design for flexible spacecraft

This paper presents a class of non-model2based position controllers for a kind of flexible spacecraft. With the controllers, one can achieve not only the closed-loop stability of the original distributed parameter system, but also the asymptotic stability of the truncated system, which is obtained through representing the deflection of the appendage by an arbitrary finite number of flexible modes. The system dynamics are not explicitly involved in the controller design and stability proof. Instead, only a very basic system energy rehtionship of the flexible spacecraft is utilized. The controllers possess several remarkable advantages over the traditional model-based ones. Numerical simulations are carried out on a kind of spacecraft with one flexible appendage and satisfactory results are obtained.     

棒材生产在线视觉计数系统研究

针对轧钢厂棒材生产工艺状况，为实现标准化打捆包装要求，设计了在线计数控制装置，研究了实时视觉图像处理，在线棒材识别算法和k级容错计数技术，并应用于含有各种干扰的实际生产过程，实现了棒材在线快速计数和分钢自动化操作．     

设备管理及监控的应用案例分析

以大型半导体制造企业为应用背景,应用在线设备监测系统TFM,对生产中心的生产设备运作信息进行实时集成和同步反馈,实现设备运行状态数据的显示、设备维护计划的查询和决策、设备生产效率的比较分析。把反映生产设备运行状态的动态数据提炼为形象直观的分析图形,实现可视化信息管理,提高生产中心现场设备管理水平。     

A review of anode materials development in solid oxide fuel cells

High temperature solid oxide fuel cell (SOFC) has prospect and potential to generate electricity from fossil fuels with high efficiency and very low greenhouse gas emissions as compared to traditional thermal power plants. In the last 10 years, there has been significant progress in the materials development and stack technologies in SOFC. The objective of this paper is to review the development of anode materials in SOFC from the viewpoint of materials microstructure and performance associated with the fabrication and optimization processes. Latest development and achievement in the Ni/Y₂O₃-ZrO₂ (Ni/YSZ) cermet anodes, alternative and conducting oxide anodes and anode-supported substrate materials are presented. Challenges and research trends based on the fundamental understanding of the materials science and engineering for the anode development for the commercially viable SOFC technologies are discussed.     

Generalized Linear Quadratic Gaussian Techniques for the Wind Benchmark Problem

This paper presents a comprehensive study of the stage-3 benchmark problem for response control of wind-excited tall buildings based on the linear quadratic gaussian (LQG) approach, and on its generalization, the k-cost-cumulant control method. For control design, the original nodal building model is first transformed into balanced modal space. The Hankel singular values (HSVs) and the power spectral density of the wind disturbances are calculated; and, based on them, a reduced-order model is derived by keeping the first six low-frequency modes. A balanced LQG (BLQG) controller is then determined by adopting the HSVs as a basis to choose the design weights. The main results of the paper are that the BLQG control design is able to come within 5–10% of the performance of the sample LQG controller supplied with the benchmark, but with control actions on the order of one-third less than the sample LQG, and with stability improvement features of a substantial nature over the range of stiffness perturbations specified in the benchmark. Finally, if the low authority BLQG controller is regarded as a one-cost-cumulant design, then with the appropriate use of the second-cost cumulant, the latter methodology is able to demonstrate how higher-authority controllers can give certain improvements in performance, but at the expense of significant investment in control action.     

Performance comparison between the training method and the numerical method of the orthogonal neural network in function approximation

The orthogonal neural network is a recently developed neural network based on the properties of orthogonal functions. It can avoid the drawbacks of traditional feedforward neural networks such as initial values of weights, number of processing elements, and slow convergence speed. Nevertheless, it needs many processing elements if a small training error is desired. Therefore, numerous data sets are required to train the orthogonal neural network. In the article, a least‐squares method is proposed to determine the exact weights by applying limited data sets. By using the Lagrange interpolation method, the desired data sets required to solve for the exact weights can be calculated. An experiment in approximating typical continuous and discrete functions is given. The Chebyshev polynomial is chosen to generate the processing elements of the orthogonal neural network. The experimental results show that the numerical method in determining the weights gives as good performance in approximation error as the known training method and the former has less convergence time. © 2004 Wiley Periodicals, Inc. Int J Int Syst 19: 1257–1275, 2004.