comprehensive appraisal on hay yield and economic value of different alfalfa varieties in first cutting

in the single planting alfalfa, hay yield of alfalfa has negative influence on available k.

而在单播的紫花苜蓿中，紫花苜蓿的干草产量与速效K呈负相关。

endemic variety cangzhou alfalfa was oppressed at hay yield, regeneration and orthotropism .

地方品种沧州苜蓿在草产量、再生性、直立性等方面均处于劣势。

the effects of wilting point, field capacity and initial amount of available soil moisture in root zone on soil moisture were positive.

凋萎湿度、田间持水量、整个根区初始土壤有效含水量对土壤水分影响为正效应；

there were 484 attendants reaching the normal threshold of stereoscopic acuity(≤ 60 seconds angle) accounting for 90% of whole examinees.

其中达到正常立体视锐度阈值≤60秒角者共484名，占全部受检者的90%。

the measurement of stereoscopic acuity

立体视锐度的测量

investigation of stereoscopic acuity among 537 attendants of the locomotive crew

537名铁路机务人员立体视觉锐度调查报告

preservation of wax gourd and oriental pickling melon

两种瓜的腌制方法

a formula of undamped natural vibration for steering system has been derivated based on the mechanical model for motorcycle steering system by which the inherent characteristics for the system are gained.

从摩托车转向系统力学模型入手，推导出转向系统无阻尼自由振动方程，从而得出系统固有特性。

the exact solution of linear, undamped forced vibration response is developed, and the damped forced vibration as well as the self-excited oscillation are obtained numerically.

推导了弹性轴向行进索无阻尼线性受迫振动解，用数值方法求得有阻尼行进索受迫振动和自激振动响应。

the trusses are discretized into space bar elements. in the part of dynamic analysis, the undamped forced vibration of structure under seismic loading is considered.

把桁架离散为空间杆单元，在动力分析部分考虑了结构在地震力作用下的无阻尼强迫振动。

finally, irbm is used to analyze the static and undamped free vibration problems in this study. 2.

本文将求逆缩减基法用于结构静力分析和无阻尼自由振动分析。（2）提出了系数缩减基法。

the optimization design of location parameters and structure parameters are discussed in this paper for the undamped vibration absorbers attached to the continuous systems under the simple harmonic excitation.

本文讨论了连续系统在简谐激励下，无阻尼吸振器位置参数和结构参数的优化问题。

a small-step searching method is introduced to find the best locations and structure parameters of the undamped vibration absorbers.

并利用小步长搜索法来确定无阻尼吸振器的最优结构参数和位置参数。

research on undamped vibration absorber attached to the continuous systems

连续系统的无阻尼动力吸振器优化设计

the development of portable wave-height gauge

轻便式浪高仪研制

the clamping block frame is connected with the half connecting blocks through fastening pieces;

夹块架与哈夫连接块通过紧固件连接；

a plurality of opposite arc-shaped holes is formed in the clamping block, and the screw plates to through the arc-shaped holes.

夹紧块内部形成有数个相对的弧形孔，各弧形孔分别供螺杆片穿过；

telescoping of the boom is carried out through telescoping cylinder and steel cable, and all booms telescope simultaneously.

吊臂的伸缩是通过伸缩油缸和钢丝绳进行，各伸缩臂同步伸缩。

the mapping relation between the telescoping cylinder and the rotation of booms is obtained, so the control of booms are performed. 2.

得到了油缸伸缩运动和臂架变幅运动之间的映射关系，实现了臂架变幅运动的制约。

the effects of the preparation conditions of polyvinyl alcohol-chitosan hydrogel on its swelling ration

聚乙烯醇-壳聚糖水凝胶制备与溶胀行为的研究