Computer implementation of efficient discrete-convolution algorithms

Translated from Kibernetika i Sistemnyi Analiz, No. 1, pp. 129–139, January–February, 1994.     

On the constraint function method for contact problems

The objective in this paper is to present some theoretical insight and valuable numerical experiences for the analysis of contact problems. We review the theoretical basis of the constraint function method for general contact problems and discuss some important characteristics of the method. In the presentation, we consider static and dynamic conditions. We then give numerical experiences with the method through the solution of some demonstrative test problems and through the results obtained in some industrial analysis cases.     

基于Client/Server数据完整性约束的实现技术

主要讨论基于Client/Server数据完整性约束及其如何实施了企业业务规则,并以SQLServer和PowerBuilder5．0为例,介绍了数据完整性约束的实现技术。     

约束规划方法在原油混输调度中的应用

应用约束规划方法建立炼厂原油混输模型,并通过搜索求解获得可操作的调度方案。约束规划允许以逻辑约束表达混输过程中的操作规则,使模型简洁直观,而对整型变量及非线性约束不敏感,则降低了模型的求解难度。选取了一个时间跨度为300小时实际调度问题作为案例,模型中包含约8000个变量和14000条约束,在普通PC机上计算求解,能够在30秒内获得调度方案,方案具有可操作性且优于人工方案,表明以约束规划方法解决原油混输调度问题是可行的。     

Computational implementation of the polarization propagator method

A computational implementation of the polarization propagator method is outlined. The program is constructed so that, in principle, there are no limitations either on the size of the basis set or on the size of the particle-hole excitation space. The lists of two-electron integrals and propagator matrices are both assumed to be too large to be kept in primary storage. A list of symbolic matrix elements is generated and the individual terms which contribute to the matrix elements are reordered so that the list of two-electron integrals can be processed sequentially. Timings for the various steps of the program are given for CO₂ as a test case. It is shown that a major part of the computational effort goes into the construction of the B(2) matrix and that the CPU and I/O times are comparable.     

Computer implementation aspects for fluid-structure interaction problems

In this paper the computer implementation aspects for fluid-structure interaction problems are presented. Special attention is placed on finite element fluid modelling, implicit-explicit transient algorithms and finite rotation effects in numerical integration of rate constitutive equations arising in large-deformation analysis. All these methodologies have been integrated into a working finite element computer code.     

The normalized normal constraint method for generating the Pareto frontier

The authors recently proposed the normal constraint (NC) method for generating a set of evenly spaced solutions on a Pareto frontier – for multiobjective optimization problems. Since few methods offer this desirable characteristic, the new method can be of significant practical use in the choice of an optimal solution in a multiobjective setting. This papers specific contribution is two-fold. First, it presents a new formulation of the NC method that incorporates a critical linear mapping of the design objectives. This mapping has the desirable property that the resulting performance of the method is entirely independent of the design objectives scales. We address here the fact that scaling issues can pose formidable difficulties. Secondly, the notion of a Pareto filter is presented and an algorithm thereof is developed. As its name suggests, a Pareto filter is an algorithm that retains only the global Pareto points, given a set of points in objective space. As is explained in the paper, the Pareto filter is useful in the application of the NC and other methods. Numerical examples are provided.     

基于约束满足的测试计划方法

测试经理在制定测试计划时,往往只能依靠个人经验,缺乏理论方法的指导,面对复杂软件系统时难以全面考虑测试模块间关系及测试人员能力等复杂因素,往往使得测试效果并不令人满意.将约束规划技术引入测试领域,结合测试计划自身特点,提出了一种全新的基于约束满足的测试计划方法.方法将软件产品划分为测试模块,通过确定各模块测试过程及过程间顺序约束、资源能力约束,对测试计划问题进行了约束建模和求解.并以项目管理软件SoftPM的测试过程为例,对方法的具体应用进行了介绍.     

Geometric constraint solving: The witness configuration method

Geometric constraint solving is a key issue in CAD, CAM and PLM. The systems of geometric constraints are today studied and decomposed with graph-based methods, before their numerical resolution. However, graph-based methods can detect only the simplest (called structural) dependences between constraints; they cannot detect subtle dependences due to theorems. To overcome these limitations, this paper proposes a new method: the system is studied (with linear algebra tools) at a witness configuration, which is intuitively similar to the unknown one, and easy to compute.     

DDR源同步接口的设计与时序约束方法

在高速I/O接口的设计中,DDR源同步接口的应用越来越广泛,因其在相同时钟频率下的数据带宽是SDR接口的两倍.由于DDR接口电路时序的复杂性,对其进行正确的时序约束也成为静态时序分析中的一个难点.结合曙光5000ASIC中的chipsct芯片,详细介绍了DDR源同步接口的设计,并且利用Synopsys公司的静态时序分析软件PrimeTime,对DDR接口接收端和发送端的时序约束方法进行了具体的分析说明.     

求解作业排序问题的一种改进修复约束满足算法

修复约束满足算法(修复法)是在完整初始解的基础上不断对变量进行修复,最终得到可行解.对此,提出一种求解flow shop排序问题的改进修复法(IRCS_WT),通过采用新的变量表达方式,设计了一种以启发式优化规则为指导的变量选择算法(LWT),并采用一种变量互换算法(LTEE)保证算法的全局搜索性能.将新算法应用于31个标准算例,与传统算法及遗传算法的优化结果进行比较,结果表明在相同运算时问下改进算法具有明显的优越性.     

基于路径约束的RFID漏读数据补全方法

无线射频识别(radio frequency identification,RFID)技术是实现制造业智能化和制造资源互联的重要信息感知技术,然而柔性制造环境下R F ID数据漏读问题严重影响了信息感知质量.通过从单阅读器内部分数据漏读和阅读器层级的整体数据漏读两个方面对RFID数据漏读问题进行分析,构建RFID数据漏读问题模型;考虑工件加工工艺路线和物料搬运路径信息约束,提出基于加工路径约束和固定滑动窗口算法集成(machining path constraint and fixed sliding window algorithm,MPC-FSWA)的漏读数据补全方法.实验研究表明,MPC-FSWA方法能对柔性制造环境下的RFID数据漏读进行有效补全.     

基于线性回归模型约束的空域数字水印

为了有效解决传统空间域水印不能抵抗线性拉伸攻击的问题,提出了一种基于线性回归模型约束的空间域水印方法。将宿主图像分成若干子块,在每一子块中充分考虑图像中相邻像素的强相关性,通过线性回归模型的方法得到一直线,然后用该直线的斜率作为水印嵌入的约束条件,最后用求均值的方法嵌入水印。水印的提取过程是嵌入过程的逆过程。实验结果表明,该水印方法不可感知性很高,能够很好的保持图像的特征部分,对灰度线性拉伸攻击有很强的鲁棒性。     

Efficient parallel implementation of the nonparaxial beam propagation method

An efficient parallel implementation of a nonparaxial beam propagation method for the numerical study of the nonlinear Helmholtz equation is presented. Our solution focuses on minimizing communication and computational demands of the method which are dependent on a nonparaxiality parameter. Performance tests carried out on different types of parallel systems behave according theoretical predictions and show that our proposal exhibits a better behavior than those solutions based on the use of conventional parallel fast Fourier transform implementations. The application of our design is illustrated in a particularly demanding scenario: the study of dark solitons at interfaces separating two defocusing Kerr media, where it is shown to play a key role.