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Online regulator design can be easily realized, as only algebraic operation is needed in the provided method. This sets up a theoretical basis for using self-tuning regulator to handle the problem of system parameter variation.

这种调节器设计方法只包括代数运算，适于在线实现，为采用自校正调节器控制，抑制系统参数扰动奠定了理论基础。

It now subtracts where it should be from where it wasn't, or vice-versa, and by differentiating this from the algebraic sum of where it shouldn't be, and where it was, it is able to obtain the deviation and its variation, which is called error.

现在应该耗损而不是从那里，或反之亦然，并从这一区分代数总和不应那里，那里有人、它能够得到偏差及其变化，叫做误差。

As we know, the algebraic sum of Hammett constants for thesubstituted donor and acceptor groups can be used to characterize the asymmetryin simple π-organic systems, to correlate the variation of NLO properties.

推拉多烯对取代基比较敏感，易于观察到结构上的变化，是一种很好的研究对象，对推拉多烯的量化计算研究可以给我们提供分子结构和非线性光学等性能之间的关系。

This is obviously influenced by the base level up and down changings, pore space variation and sediment alimentation. Through analysing the relationship between the course of base level up and down cycles of high resolution sequence strata and the reservoir physical behavior, six heterogeneity models of diff...

通过高分辨率层序地层的短期基准面升、降旋回过程与储集物性关系的分析，建立了6种不同沉积微相的非均质性模式，探讨了向上变深、向上变浅的非对称型和向上变深后复变浅的对称型短期基准面旋回层序对储层非均质性特征的控制作用

A modified method of free radical alkylation has been using for synthesizing of quinone derivatives with an alkyl side chain variation.

应用经过改进的自由基烷基化新方法，合成了一系列的具有长侧链结构的苯醌类化合物。

Results of the HPLC analysis of nutritional compositions showed that there was a significant variation in allantoin among the cultivars.

HPLC成分分析结果显示，各品系恒春山药之间Allantoin成分的含量有明显的差异。

Random changes in allele frequency can lead to fixation and the progressive loss of genetic variation from the population.

基因频率的随机变化导致来自种群的遗传变异的固定和逐渐丧失。

During the postgenomics era the information about genomic sequence and gene functions provides a new foundation for evolutionary biology and ecology As the first whole-genome sequenced plant Arabidopsis thaliana and its wild relatives have played a critical role in understanding the evolution of genomics and speciation Both A halleri and A lyrata are closely related to the model species A thaliana A halleri ssp gemmifera occurs in northeastern China Japan and Taiwan; while its sister A halleri ssp halleri is mainly distributed in Europe Geographical barriers such as Tienshan Mountain Range isolate these intraspecific sisters Likewise A lyrata ssp kamchatica and ssp lyrata occur in East Asia and North America respectively Such distribution patterns seem to be consistent with allopartic speciation The comparison between ancestral and extant polymorphism by multilocus can be informative about the population genetics of speciation In this study we collected and analyzed DNA sequences of 98 genes from four wild relatives of A thaliana A halleri ssp gemmifera A halleri ssp halleri A lyrata ssp kamchatica and A lyrata ssp lyrata The ancestral states of these four species were compared to each other in terms of level of genetic variation However the ancestral species at the time of speciation were substantially more polymorphic than the extant geographical populations The observations are not fully compatible with speciation by strict allopatry At some species pairs parapatric speciation seems more reasonable in speciation of Arabidopsis The 98 gene sequences are also used for the congruence test between gene genealogy and species phylogeny Only 28 genes support the species phylogeny but there are 23 genes supports another major genealogy { lyrata} thaliana Based on the phylogenetic position change of A lyrata ssp kamchatica and Ks value for each species pair suggested the recent directional gene flow between A halleri ssp gemmifera and A lyrata ssp kamchatica

阿拉伯芥是第一个完成基因体定序的开花植物，其基因体资讯提供植物学研究的重要依据；在解析阿拉伯芥属物种的亲缘关系以及种化机制等重要的演化议题时，阿拉伯芥近缘的野生物种自然成了不可或缺的关键；跟阿拉伯芥近缘的物种包括A halleri及A lyrata，其中A halleri ssp gemmifera主要分布於中国东北、日本以及台湾，与近缘的A halleri ssp halleri其分布於欧洲隔著天山及大陆的障蔽，而A lyrata ssp kamchatica主要分布於东北亚及台湾，与分布於北美五大湖的A lyrata ssp lyrata被北极圈所分隔，这样的分布模式暗示异域种化的可能。藉由多基因分析比较祖先物种与现生物种遗传歧异度的相关可提供讯息探讨种化时期的族群遗传结构，本研究针对A halleri ssp gemmifera、A halleri ssp halleri及A lyrata ssp kamchatica、A lyrata ssp lyrata四个物种，两对互为亚种的姊妹群，以阿拉伯芥为外群进行研究，在四个物种完成98个同源基因的分子序列，利用套装软体MCMCcoal来估算祖先物种的遗传变异，亦估算现生物种的核苷酸歧异度，观察到？多物种配对中祖先物种遗传多型性大於现生物种DNA歧异度，显示异域种化模型并无法完全解释阿拉伯芥属物种的种化模式，在某些物种配对间邻域种化模式应比异域种化更为可能；在基因树与物种树的比较，98个基因片段的亲缘模式只有28个是与已知物种树一致的，有23个基因其树状图支持{ lyrata} thaliana的型式，藉由kamchatica位置的变化以及估算各物种配对间的平均同义置换率，推测在A halleri ssp gemmifera与A lyrata ssp kamchatica间具有近代的单方向基因交流。

Apomixis,wide compatibility,allopolyploidization were used to select allopolyploid rice and enlarge its range of inheritance and variation,and increase its output,quality and resistance to disease and pest by a big margin.

通过无融合生殖、广亲和、异源多倍体化的利用，选育异源多倍体水稻，增加它的遗传变异范围，大幅度提高水稻的产量、质量和抗性。3。

The best indicators of consistently associated with temporal variation are O3/NOz, H2O2/NOz, H2O2/, and NOy. However there is significant difference for almost all indicator species at the downwind sites.

不同时间一致性最高的指标则为O3/NOz、H2O2/NOz、H2O2/、NOy，在下风处各光化指标对时间的变异性有较显著之差异存在。

There had been a moment during the breakfast meeting, though, after the backslapping and the small talk and when all of us were seated, with Vice President Cheney eating his eggs Benedict impassively and Karl Rove at the far end of the table discreetly checking his BlackBerry, that I witnessed a different side of the man.

那次早餐会期间，在表示过关心和寒暄以后，我们所有人坐了下来，我注意观察了一下，副总统切尼面无表情地吃着班尼迪克蛋（Eggs benedict，源自美国，以英式松饼、火腿、水煮蛋以及荷兰酱组合而成），卡尔。罗夫在餐桌的远端谨慎地经常查看他的黑莓手机，我目睹了他所不为人知的一面。

Talk Undelete failed; someone else may have undeleted the page first.

Talk 无法删除选定的页面或图像（它可能已经被其他人删除了）。