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1.
有等式约束优化问题的粒子群优化算法   总被引:3,自引:5,他引:3  
目前大多数粒子群优化算法针对无约束优化问题或不等式约束优化问题,求解有等式约束优化问题的方法是把每个等式约束变成两个不等式约束,这种方法的缺点是在进化过程中粒子位置很难满足等式约束条件,影响了收敛速度和解的精度。提出了求解有等式约束优化问题的两种新粒子群优化算法,数值试验结果表明,算法是有效的。  相似文献   

2.
为了在软件静态测试中检测上下文相关的过程间故障,提出一种应用过程约束信息的方法.首先通过约束模式状态机描述过程间故障模式,并在此基础上定义过程外部向量及约束向量;然后在相关数据流方程的基础上给出过程外部向量和约束向量的生成算法,以及约束向量的传播和使用算法;最后在现有实验环境软件缺陷检测系统(DTS)的基础上,对比应用...  相似文献   

3.
体差不等式测试为适用于软件流水领域的高维数组数据相关性分析算法,通过使用更严格的限制条件,该算法可以获得比传统数据相关性分析方法更精确的结果。文章展开该算法的实验研究。实验表明,虽然体差不等式测试算法只能针对实可行解域进行数据相关性分析,但所得到的结果仍然与实际情况相吻合。对于科学计算循环中出现的大多数数据相关性判定问题,使用体差不等式测试算法可以获得很好的效果。  相似文献   

4.
给出了二维数组的体差不等式测试算法,并证明二维数组的体差不等式测试算法具有多项式时间复杂度。相对于直接求解,体差不等式测试算法的时间复杂度要小得多。实验表明,对于科学计算循环中出现的大多数数据相关性判定问题,使用体差不等式测试算法可以获得很好的结果。  相似文献   

5.
胡云卿  刘兴高  薛安克 《自动化学报》2013,39(12):1996-2001
控制变量参数化(Control variable parameterization,CVP)方法是目前求解流程工业中最优操作问题的主流数值方法,但如果问题中包含路径约束,特别是不等式路径约束时,CVP方法则需要考虑专门的处理手段.为了克服该缺点,本文提出一种基于L1精确惩罚函数的方法,能够有效处理关于控制变量、状态变量、甚至控制变量/状态变量复杂耦合形式下的不等式路径约束.此外,为了能使用基于梯度的成熟优化算法,本文还引进了最新出现的光滑化技巧对非光滑的惩罚项进行磨光.最终得到了能高效处理不等式路径约束的改进型CVP架构,并给出相应数值算法.经典的带不等式路径约束最优控制问题上的测试结果及与国外文献报道的比较研究表明:本文所提出的改进型CVP 架构及相应算法在精度和效率上兼有良好表现.  相似文献   

6.
邹士新  张妍 《计算机仿真》2010,27(2):52-54,58
在特征值空间中,利用接收数据协方差阵的主特征向量,与扰动环境参数生成的拷贝场向量协方差阵的主特征向量,构造了一种巴特利特型的匹配场定位算法,它对环境参数失配稳健,但是带有很高的旁瓣级。引入一种约束优化机制,以最大化目标区域的空间平均的输出功率与搜索区域空间平均的功率比为目标,得到一个经过优化的观测数据向量。使用数据向量对定位表面的旁瓣进行约束抑制,在保持目标区域输出功率的同时,有效降低搜索区域的背景功率。实测数据分析表明,该算法能有效抑制旁瓣,提高定位性能。  相似文献   

7.
针对一般线性约束的Petri网控制器设计方法   总被引:6,自引:0,他引:6       下载免费PDF全文
王寿光  颜钢锋 《软件学报》2005,16(3):419-426
针对基于Petri网离散事件系统关于标识向量和Parikh向量的不等式约束反馈控制器设计问题,提出一种新的控制器设计方法.该方法首先利用Petri网的状态方程把关于标识向量和Parikh向量的不等式约束转变成关于Parikh向量的不等式约束,然后基于Petri网库所是关于Parikh向量的不等式约束的观点构造控制器.最后将该方法与Iordache和Moody提出的方法作比较,实验结果显示该方法更简单、有效.  相似文献   

8.
将附有条件的最短路径概括为点约束、边约束和属性约束的最短路径问题。以栅格数据模型为图或网络描述方式,基于贪心算法思想,提出栅格数据模型中附有条件的最短路径算法。最后,通过实例进行了算法测试,结果表明栅格数据模型中附有条件的最短路径算法是完全可行和有效的。  相似文献   

9.
结合基于可行性规则的约束处理技术,构造了一个求解约束优化问题的自适应杂交差分演化模拟退火算法。该算法以差分演化算法为基础,用模拟退火策略来增强种群的多样性,用一个基于可行性规则的约束处理技术来处理不等式约束,且自适应化关键控制参数,避开人为控制参数的困难。在标准测试集上的实验结果表明该算法的有效性,与同类算法的比较表明了该算法的优越性。  相似文献   

10.
针对目前虚拟环境下碰撞检测问题中的方向包围盒(OBB)相交测试复杂度高的问题,提出一种基于线性不等式组有效约束的快速OBB相交测试算法.首先用线性不等式组描述OBB,并给出了算法矩阵降维过程中的数学理论条件,即有效约束定理;然后用有效约束不等式确定的超平面对应的行化简原系数矩阵,即针对被操作矩阵的第一列元素对矩阵进行初等变换,必要时剔除相关行列,以实现降维;再在静态与动态(旋转和平移)案例中进行测试速度与准确率的对比;最后对算法的准确性及时间复杂度进行简要分析.实验结果表明,该算法的测试速度是传统算法的2~3倍,且具有整体优越性.  相似文献   

11.
For a compiler, dependence direction vectors are the key structure for many loop parallelizing transformations. More powerful transformations require knowing the values of the associated distances. However, this generally involves solving many problems. In this paper, we consider a hierarchical set of problems which differ only in direction vectors, as in the framework introduced by Burke and Cytron. Firstly, we solve the basic problem of the existence of a dependence without direction constraints, using a fast and exact algorithm composed of a pre-processing phase of reduction and of an integer simplex resolution. We propose a new “basic” algorithm. Secondly, if a solution exists, we define three new problems, each of them being obtained by adding a constraint associated with one of the three possible direction vectors relative to the first loop index. For each of these problems, if a solution exists, we define three enlarged similar problems involved by the second loop index, and so forth until the last index. The amount of computation for each new problem is very low. Information on the values of the distances is provided. The Janus Test, implemented at INRIA, has been embedded in the parallelizer built within the esprit project Compare and in the PARTITA tool of the EUREKA project EUROTOPS. Due to its robustness, it could be applied to more complex problems in data dependence and data flow analysis.  相似文献   

12.
Loop transformations,such as loop interchange,reversal and skewing,have been unified under linear matrix transformations.A legal transformation matrix is usually generated based upon distance vectors or direction vectors.Unfortunately,for some nested loops,distance vectors may not be computable and direction vectors, Unfortunately,for some nested loops,distance vectors may not be computable and direction vectors,on the other hand,may not contain useful information.We propose the use of linear equations or inequalities of distance vectors to approximate data dependence.This approach is advantageous since(1) many loops having no constant distance vectors have very simple equations of distance vectors;(2) these equations contain more information than direction vectors do,thus the chance of exploiting potential parallelism is improved.In general,the equations or inequalities that approximate the data dependence of a given nested loop is not unique,hence classification is discussed for the purpose of loop transformationEfficient algorithms are developed to generate all kinds of linear equations of distance vectors for a given nested loop.The issue of how to obtain a desired transformation matrix from those equations is also addressed.  相似文献   

13.
Precise value-based data dependence analysis for scalars is useful for advanced compiler optimizations. The new method presented here for flow and output dependence uses Factored Use and Def chains (FUD chains), our interpretation and extension of Static Single Assignment. It is precise with respect to conditional control flow and dependence vectors. Our method detects dependences which are independent with respect to arbitrary loop nesting, as well as loop-carried dependences. A loop-carried dependence is further classified as being carried from the previous iteration, with distance 1, or from any previous iteration, with direction <. This precision cannot be achieved by traditional analysis, such as dominator information or reaching definitions. To compute anti- and input dependence, we use Factored Redef-Use chains, which are related to FUD chains. We are not aware of any prior work which explicitly deals with scalar data dependence utilizing a sparse graph representation. A preliminary version of this paper appeared in theSeventh Anual Workshop on Languages and Compilers for Parallel Computing, August 1994. Supported in part by NSF Grant CCR-9113885 and a grant from Intel Corporation and the Oregon Advanced Computing Institute.  相似文献   

14.
Data dependence and its application to parallel processing   总被引:8,自引:0,他引:8  
Data dependence testing is required to detect parallelism in programs. In this paper data dependence concepts and data dependence direction vectors are reviewed. Data dependence computation in parallel and vector constructs as well as serialdo loops is covered. Several transformations that require data dependence are given as examples, such as vectorization (translating serial code into vector code), concurrentization (translating serial code into concurrent code for multiprocessors), scalarization (translating vector or concurrent code into serial code for a scalar uniprocessor), loop interchanging and loop fusion. The details of data dependence testing including several data dependence decision algorithms are given.  相似文献   

15.
16.
Thomas  Wenchan  Tingshu   《Automatica》2009,45(9):2046-2051
The objective of this paper is to develop numerically simple and effective methods for system analysis using truncated ellipsoids. The paper studies linear time-invariant systems subject to persistent disturbance and state constraint. The maximal output under a set of initial conditions and the overshoot under a given step input are estimated. Attempts are also made to detect an invariant set, as large as possible, within state constraint. The results are based on the set invariance condition for the truncated ellipsoid, and a characterization of the set where the output possibly reaches a local extrema. The analysis problems are converted into optimization problems whose constraints become linear matrix inequalities when a few variables are fixed. Numerical examples demonstrate the effectiveness of the truncated ellipsoid and the proposed methods.  相似文献   

17.
Constraints are an effective tool to define sets of data by means of logical formulae. Our goal here is to survey the notion of constraint system and to give examples of constraint systems operating on various domains, such as natural, rational or real numbers, finite domains, and term domains. We classify the different methods used for solving constraints, syntactic methods based on transformations, semantic methods based on adequate representations of constraints, hybrid methods combining transformations and enumerations. The concepts and methods are illustrated via examples. We also discuss applications of constraints to various fields, such as programming, operations research, and theorem proving.  相似文献   

18.
采用约束关系依赖图(CRDG)表达耦合约束之间的依赖关系,从而建立数值与符号耦合约束模型.提出耦合约束的求解算法:对CRDG进行最小独立子图分解,对存在耦合约束的子图用"孪生变量法"进行一阶解耦,对没有耦合约束的子图用传统方法进行独立求解,求解之后再对孪生变量进行等效性验算.该耦合约束模型及其求解算法拓展了传统约束理论,实现了教学求解和推理求解有机地结合.  相似文献   

19.
文章对SCHEMA描述的XML文档的数据模型进行了集合分析,并在其描述的集合上定义了关联依赖关系、值依赖关系和两种取值关系,根据这些关系及SCHEMA规范所规定的约束,建立了一组从SCHEMA到关系型数据库的映射规则,并且证明由此规则得到的映射是完备的,而且映射后的关系符合第三范式。文章最后提出了可进一步研究的问题和方向。  相似文献   

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