查询词典 genetic

In this paper,an improved genetic algorithm is proposed to overcome the shortage of early convergence and stagnation in the traditional genetic algorithm,which is based on unconvertible rate of crossover operator and mutation operator.Moreover,the user page interest measure threshold is introduced into the association rules mining.

针对传统遗传算法在提取关联规则问题时常采用固定染色体交叉概率和染色体变异概率，容易出现早熟、收敛速度较慢的问题，提出了改进的遗传算法，并在关联规则的提取中增加了用户页面兴趣度这一阈值，成功地运用到某商业网站服务器日志挖掘。

Secondly,proposed an new scheme that the double population genetic algorithm used the self-adaptable crossover operator and mutation operator according to the shortage of early convergence and stagnation in the traditional double population genetic algorithm based on unconvertible rate of crossover operator and mutation operator.

摘 要：介绍了图像关联规则的相关概念，描述了传统的双种群遗传算法的执行过程；针对采用固定染色体交叉概率和染色体变异概率容易出现早熟、收敛速度较慢等问题，设计出了能自适应调整的染色体交叉算子和变异算子。

Low resolution was obtained in genetic variation investigation of different cowpea cultivated germplasm of Vigna unguiculata based on ITS sequence data, while good results could be obtained in genetic diversity and phylogeny of differern species of genus Vigna.

RAPD可以用于种下的遗传多样性研究。但基于随机引物的RAPD-PCR扩增，受实验中各种因素的影响较大，导致数据获得的重复性不是很好、且不可移植。因此只能作为一种辅助方法。从技术上讲，为保证实验条件的一致性，应该一次PCR反应中对所有的研究对象进行扩增，并在扩增片段的电泳分离检测时尽量保持条件的一致。

Allelic loss at specific chromosomal loci is a common genetic alteration in human tumours and is thought to be critical for unmasking the recessive genetic changes for tumorigenesis.

人类食管癌的基因丢失研究染色体上座位特异性等位基因丢失是人类肿瘤基因组中一个普遍的遗传改变现象。

The definition and detective methods of genetic diversity were reviewed in this paper. It indicated that these various genetic diversity measuring methods are unreplaceable.

文中对植物遗传多样性的涵义和检测方法进行了概述，认为各种水平的遗传多样性检测方法在特定的研究领域、研究对象中都有不可替代的作用。

Results After six passages in BHK-21 cells, cytopathic effect was observed by microscopy. The rescued virus was rejuvenated once in unweaned mice, and then came back to cell passage. We found that the poly tract of rescued virus was shortened when the virus was passaged twice in BHK-21 cells. Although the data of LD50 in mice and TCID50 in BHK-21 cells showed that the virulence and infectivity of genetic engineering viruses were lower than its parental virus, no significant difference was observed between the genetic engineering viruses with the different length poly tract.

我们发现，基因工程毒在BHK-21上连续传代至第6代时，可见明显的致细胞病变效应(cytopathic effect，CPE)；在经过一代乳鼠接种之后再重新适应到BHK-21细胞的过程中，poly区段出现了缩短现象；乳鼠致病性试验和BHK-21细胞TCID50测定结果表明，尽管基因工程毒与母本毒相比毒力偏低，但含有不同长度poly的基因工程毒之间并无显著差异。

Unweighted Pair Group with Mathematic Average was used to construct genetic tree of all individuals tested based on genetic distance.

对46份样本进行UPGMA聚类，研究结果表明：全同胞的犬在较高的相似水平上聚为l组。3品系犬的遗传背景复杂程度依次为：狼青＞黑背＞草黄。

Or 10.40％ of the variation was partitioned among voltinism populations. The Nm (4. 3065) showed that there was to some extent gene flow among three voltinism populations. The average Nei's genetic identity was 0.9637. The genetic distance between V1 population and cultivated V1 population was the biggest (0.0438) and the less was 0.0370 between V1 population and V2 population.

Nei基因多样性指数也是2化群体最大（0.2631），1化群体次之（0.2485），培育1化性群体最小（0.1709），3个群体之间的遗传分化系数为0.1040，即3个化性群体之间的遗传变异占到总遗传变异的10.40％。3个化性群体之间的基因流达到4.3065，表明化性群体间存在着一定程度的基因交流。3个群体之间的遗传一致度为0.9637，遗传距离以培育1化性群体与1化性群体最大（0.0438），以1化群体与2化群体最小（0.0370）。

At present this procedure can be used to evaluate the genetic effects of individual major genes (up to 2-3 major genes) and the collective genetic effects of polygenes as well as their heritability values.

目前该方法可以检验2～3个主基因的个别遗传效应、多基因整体的遗传效应和两者的遗传率。

Dynamic matrix predictive control algorithm based on genetic algorithm optimizes different chromosomes syngen by genetic algorithm, and gets the most parameter set through decoding the most individual, and counts contemporary control series increment and brings to controlled objects.

基于遗传算法的动态矩阵预测控制算法在每个采样时刻，用遗传算法优化不同的染色体种群，由最优个体解码得到最优参数集，再计算当前控制序列增量并施加到被控对象。

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。