查询词典 parallel algorithm

Optimal algorithm of combined nonlinear Hopfield network appears powerful validity in solving nonlinear planning, which includes nonlinear objective function, linear constrains and high-demension of decision-making variants, for its ability of nonlinear parallel computation. It is prominent among optimal algorithms because of its function of simply implement with electrocircuit hardware. Genetic algorithm is expressly suitable for optimal calculation regarding the planning of massive, highly nonlinear, inconsecutively differentiable and multiobjective function as well as objective function without analytical expression. However, it inclines to prematurity, as well as its limitation in ability of partial optimal search. Introducing the optimal algorithm of niche genetic simulated annealing to standard Genetic algorithm, can therefore improve the full-scale or partial search ability of Genetic algorithm effectively. It has a far-flung perspective in the field of systemic planning of water pollution control.

组合式非线性Hopfield网络优化算法所具有的非线性大规模并行计算能力在求解具有非线性目标函数、线性约束条件及高维决策变量的非线性规划问题方面显示出了强大的生命力，它易于电路硬件实现的功能更是在优化算法中独树一帜；遗传算法采用概率搜索技术，不受目标函数与约束条件的限制，特别适合大规模、高度非线性的不连续可微的多峰目标函数及无解析表达式的目标函数的规划问题的优化计算，但其存在容易早熟、局部寻优能力较差等缺点，本文在标准遗传算法中引入小生境技术及模拟退火算法有效地改善遗传算法的全局和局部搜索性能，提高了全局最优解的寻优质量，小生境遗传退火模拟优化算法在水污染控制系统规划中的应用前景极为广阔。

In generic mathematical approximation methods Chebyshev multinomial approximation algorithm has better effect on reducing approximation error. This paper brought forward a parallel Chebyshev multinomial approximation algorithm based on a unique representation of complex curve, and implemented the parallel program in two Java methods.

常用的数学逼近法中切比雪夫多项式拟和法误差较小，对此，提出一种基於复杂曲线表示的切比雪夫多项式拟合并行算法，并采用两种Java方案实现并行程序。

In order to improve the kinematics accuracy of parallel machine tool and to simplify error resource model (including 42 errors), a new kind of algorithm on parallel mechanism structural errors reorganization is proposed in this paper based on the fast algorithm of parallel mechanism forward displacement analysis.

为了提高并联机床的运动精度，针对简化误差源模型（含42个误差量），基于并联机构位置正解的快速算法提出了一种结构误差识别的新算法。

A high-performance modular exponentiation coprocessor, SEA, is presented here, and three novel ways are employed. First, a parallel binary modular exponentiation algorithm is used to decrease cycles, and a high radix Montgomery modular multiplication algorithm is modified to the radix based high radix Montgomery modular multiplication algorithm to increase the frequency; second when mapping algorithms to a systolic array, modular square and modular multiplication are alternatively computed to cover up the dependencies between iterations in the RBHRMMM algorithm and the bypass is used to eliminate the dependencies in the PBME algorithm; third, multipliers are split first, and then accumulations are compressed as partial products to decrease carry propagation delay in the critical path.

SEA是一种针对大数模幂的高性能协处理器，其主要采用如下3种加速方法：①采用二进位并行模幂算法和以基数长度为处理字长的高基数Montgomery算法；②将算法映射到脉动阵列处理结构，并交替计算平方和乘以掩盖RBHRMMM算法中的相关，同时应用定向技术消除PBME算法中的相关；③基於"先拆分乘法、后将累加压缩"的思想优化关键路径。

The traditional query tree optimization methods,parallel database optimization methods based on left linear trees and right linear trees,bushy trees,and operation of the forest,have their own pros and cons,they have been more in-depth and maturity of the study.The query optimization method based on multiple weighted tree has studied its model of parallel query plan,its complexity model of parallel query plan and query optimization algorithms.The semantic query method transforms an inquiry into one or several semantic equivalence inquiries then has to find and implement a strategy to achieve a better query.Agent-based parallel database query optimization using Multi-Agent technology to automatically search the integrity constraint conditions which are related to the determined query,there for,the efficiency between several relations' joins has been greatly improved.The parallel optimization algorithm,based on genetic algorithm which is suitable for multi-joins of cluster environment,has deeply studied the relations storage options,multi-joins query optimization and query processing and other key technologies based on cluster parallel database.

传统的查询树优化方法，即基于左线性树、右线性树、浓密树、操作森林的并行数据库查询优化方法，各有优劣，对其的研究比较深入、成熟；基于多重加权树的查询优化方法，研究了其并行查询计划模型、并行查询计划的复杂性模型和查询优化算法；语义查询优化方法将一个查询变换成一个或数个语义等价的查询，进而寻找并执行这些等价查询中具有较好实现策略的一个；基于Agent的并行数据库查询优化采用Multi-Agent技术自动查找与给定查询有关的完整性约束条件，使得多个关系间连接操作的效率得到很大的提高；基于遗传算法的并行优化算法，深入研究了基于机群并行数据库中关系存储的选择、多连接查询优化和查询处理等关键技术。

Finally, the parallel Genetic Algorithm is discussed and the parallel Genetic Algorithm for shortest route choice is given.

最后，本文还探讨了遗传算法并行计算的实现方式及其特点和适用范围，并选择了适用于最优路径计算的并行遗传算法。

On the basement of conventional direct fan-beam reconstruction, this paper gives a newly improved algorithm-"fast filtering-backprojection". This method utilizes the symmetrical circle geometry to sample projection data, and reconstructs image on the Polarcoordinate firstly, then translates this reconstructed image onto the cartesian coordinate system with two interpolating operations so that the computer can show the result image on the VGA screen. This algorithm rebates the calculating backprojection greatly, and shortens a few times of reconstructing time than same kinds of means. With the size of image enlarging, the reconstructing time abates with 2 exponent times. In addition, according to the idea of parallel-beam, we rearrange the fan-beams and reconstruct image using parallel-beam method fastly. The rearranging constraint condition is given here.

本文首先在传统的扇束直接重建方法的基础上，提出了一个改进的快速滤波反投影重建算法，它利用旋转采集投影数据的圆周对称的几何关系，先在极坐标系统内进行图象的重建，然后通过两次内插运算再将图象转换到计算机显示方式下的笛卡尔坐标系中去，该方法将以往的直接重建方法中的反投影时所需的运算大大降低，并将重建时间比同类方法缩短了几倍，而且随着重建图象的尺寸的增大，重建时间以2的指数次方倍相对缩短，并获得了较好质量的重建图象；另外，又根据平行束投影重建图象的思想，对扇形射束进行了重排，然后利用平行束重建图象的方法进行扇束的重建，并推导了&扇束重排重建图象&方法的约束条件。

The experiment result show that the designed parallel algorithm has high speedup on NOW.

实验结果表明，设计的并行算法在网络并行计算环境中具有较高的加速比。

Through the performance analysis and experiment, it can be easily concluded that this parallel algorithm works well and has speedup performance.

理论分析和实验表明算法是有效的，具有良好的加速比。

In this chapter, we analyze a parallel algorithm for the computation of twodimensional image moments on a linear array.

这个算法极大的利用了计算的并行性，理论计算复杂度为O，加速比是〓。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。