The bifilar pendulum absorber is used to reduce the inplane longitudinal and lateral excitation forces and it is mounted to the rotor hub of a helicopter.

The equation of dynamics of bifilar pendulum has been sol-ved in this paper. The formulas to calculate free swing period under small and large angular amplitude conditions are given, and error analysis is discussed briefly.

本文求解了双线摆的动力学方程，得出了计算小角度摆动和大角度摆动时双线摆动周期的计算公式，并进行了误差分析。

Free Swing Period of Bifilar Pendulum

双线摆的摆动周期

A bifilar-helix wiggler used in a free-electron laser

用于自由电子激光器的双绕螺线波荡器

Double-sided plush bifilar helix biperiodic electrostatic focusing

双螺线双周期静电聚焦

As the requirement for high temperature up to several hundreds tolerant, this paper only introduces the analysis for bifilar helix, waveguide element and cross dipole element. 2.

由于设计的圆极化阵列要求能够经受几百度高温的考验，这里主要分析了螺旋单元，波导单元和交叉偶极子单元。

Double bifilar helix linear polarized wiggler field

双-双绕螺旋线极化摇摆器磁场

Study and Design of New Type Bifilar Helix Antenna

一种新型双臂螺旋天线的研究与设计

Clinical Observations of Combined with Acupuncture and Tuina Treatment in Enuresis of Recessive Bifid Spine

针推结合治疗隐性脊柱裂遗尿的临床研究

Its flower bud is mixed bud and forms in the year before flowering and fruiting, but it is difficult to control the formation of flower bud, and the phenomenon of biennial bearing that influencing the production is prone to appears by poor management.

其花芽是混合芽，形成于开花结果的前一年，但花芽形成控制困难，管理不善很容易出现大小年，影响产量。

The ratio of dry matter distribution to annual branch, biennial branch and capillary root was higher than weeping peach. That to coarse and fine roots was lower than weeping peach. 5.

柱型桃干物质分配到一年生枝、二年生枝及毛细根比例高于垂枝桃，而分配到粗根和细根的比例低于垂枝桃。

At present, the rate of broken biennial root in cutting sugarcane is very high, exceeds more than 20%, and is arriving at 35% when it works in sweat field.

目前切割器切割甘蔗的破头率较大，超过20%，湿地作业达到35%以上。

Higher the rate of broken biennial root is, lower the germination of sugarcane is in the next year, and the output of sugarcane accordingly.

甘蔗破头率高，来年甘蔗发芽率就低，甘蔗的产量相应地就低。

However, there are a lot of factors that affect the cutting quality ( the rate of broken biennial root) of cutter.

而影响切割器切割质量（破头率）的因素较多，因此，有必要对甘蔗切割器影响切割质量的各因素进行优化研究，提高其切割质量。

Mechanism and Optimization Study of Affecting Factors on the Rate of Broken Biennial Root of Dual Base Cutter of Sugarcane Harvester

双圆盘切割器切割甘蔗破头率影响因素的优化及机理研究

Experimental Study on Influencing Factors of Broken Biennial Root Rate for a Single Base Cutter of Sugarcane Harvester

单圆盘甘蔗切割器切割破头率影响因素的试验

The damage of stubble will influence the quality of its biennial root.

甘蔗根茬破坏情况影响到宿根质量。

Biennial yellow-flowered Eurasian plant having aromatic leaves used as carminative or flavoring agent; widely cultivated especially as green manure or cover crop.

两年生欧亚植物，花黄色，其叶芳香，用做祛风剂或调味品；广泛栽培，尤其作绿肥或覆盖作物。

Biennial Eurasian plant usually having a swollen edible root; widely cultivated as a food crop.

两年生欧亚植物，通常有膨胀的可食根；作为粮食作物培植广泛。

DC. Methods: Choose the biennial plant, get rid of50% alabastrums of them, but make another bloom and fruit.

方法：选择二年生长势基本相同的植株，将其中的50%去除花蕾，另外的50%任其开花结果。

The proportion of annual plant and biennial plant decrease gradually and the proportion of perennial plant increases gradually in the course of enclosure.

围封过程中的沙化草地，土壤种子库群落组成中，1、2年生植物所占比例逐渐减小，多年生植物所占比例均逐渐增加。