根

Compared with the traditionalroot-locus method, the root-locus method proposed in this dissertation has thefollowing characters:1 The poles location is expressed by polar coordinates.2 The poles location is computed directly.3 The object includes the closed-loop systems and controllers.4 The influence of the parameters on the polar radius and angle can be studied mainly by differential operation.5 The relationship between the polar radius and angle can be studied mainly by differential operation.

与传统的根轨迹法相比，本论文中所采用的根轨迹法具有以下的特点：1 使用极坐标表示极点的位置2 直接计算闭环极点的分布3 研究对象包括闭环系统与控制器4 以微分运算为主要手段，研究了参量的变化对极点的极径和辐角的影响5 以微分运算为主要手段，研究了极点的极径与辐角间的关系本论文从研究Dahlin 控制器振铃现象的成因及消除方法出发，主要进行了以下方面的研究：运用根轨迹法对Dahlin 控制器进行了动态性能分析。

Tentativea analysis trace selenium in radix puerariae and its soil property by microwave digesion-single sweep polarograph

采用微波消解单扫描极谱法测定了葛根及其种植土壤中微量硒的含量，并做了初步分析，为葛根产品的研发提供重要依据，也为进一步开发葛根优良品种和平衡施肥提供科学信息和依据。

When thepolynomial has at least two simple real roots,sequences of critical values of timedelays corresponding to each positive root can be derived.

而当该多项式有二个及二个以上的简单正根时，稳定性切换次数主要取决于两方面：一是该多项式的正根的个数，二是该多项式的每个正根对应的临界时滞序列中相邻两项差的大小关系来确定。

There is a linear positive correlation between root hydraulic conductivity and root zone soil moisture and also soil temperature showed a positive correlation with root hydraulic conductivity.

根系水分传导与根区土壤含水量和土壤温度均呈线性正相关关系，部分根区滴灌方式提高了根区土壤温度也是引起根系水分传导提高的一个重要因素。

Objective: To investigate the root canal configuration and the incidence and location of the isthmus in extracted maxillary second premolar with single root.

目的：研究离体单根的上颌第二前磨牙根尖1—6mm处根管形态及根管峡部的发生率和位置的情况。

Influence of various parameters including ratio of nonprestressed reinforcement, ratio of unbonded prestressing tendon, span-depth ratio, effective prestress, cylindrically compressive strength of concrete, ultimate tensive strength of prestressing tendon, yield strength of nonprestressed reinforcement and loading pattern on the behavior of unbonded prestressed concrete beams and the ultimate stress in tendon, f_, are investigated in detail. Parameters having important influence on second-order effects of externally prest

本文设计了8个系列共76根体内无粘结预应力梁，以及2个系列共21根体外预应力梁和3根体内无粘结预应力对比梁，利用提出的有限元模型对这些梁进行非线性全过程分析，详细研究了各种参数诸如非预应力筋配筋率、无粘结预应

Rhizomes short and vertical or long and horizontal; rhizomes and roots often pungently aromatic.

根状茎短和垂直的或长和水平；根状茎和根通常冲味的芳香。

The results showed that the coefficient of raicel decreased firstly in a short distance, and then kept stable form radicel base to radicel apical.

通过对胚根分支系数研究表明：从根基部到根尖，呈现出先递减，然后保持稳定的趋势，采用经验分布函数表示；同时，用四种分支类型已能描述玉米胚根分支特征，且它们的特征参数在一定范围内随机分布。

According to the first and second references, a sufficiency and necessity condition on rational root of integral coefficients polynomial is put forward and a reduced method of testing the rational root is also shown in this paper.

摘要给出了整系数多项式有理根的一个必要条件，从而得到整系数多项式有理根检验的一个简化方法，达到了简化整系数多项式有理根检验的目的。

To realize reduced equivalent representation for functional dependency set, sameroot row, same-class row and same-class row family are presented, merging rules of same-root row in a schema matrix are defined, merging algorithm of same-root row and solving algorithm of same-class row family in a schema matrix are discussed.

为了实现函数依赖集的最简等价表示，提出了同根行、同类行、同类行族的概念，定义了模式矩阵M中同根行的合并运算规则，讨论了模式矩阵M中同根行合并算法，同类行族求解算法。

Fancy gold-plated dangling earrings with facetted White Opal crystals.

花式镀金悬垂耳环与facetted白欧泊水晶。

This essay chooses the study aim from biology teachers in middle school in Shi Jiazhuang which tells us that most of the middle school biology teachers in Shi Jiazhuang have the"burnout", lower successfulness, individualize.

本文选取石家庄市初中生物教师作为研究对象，运用问卷调查的方法对石家庄市初中生物教师职业倦怠的现状进行调查，调查结果发现，石家庄市初中生物教师这一群体普遍存在职业倦怠，情感枯竭程度偏高，成就感偏低，去个性化程度最为严重。