查询词典 square wave

Periodic fluid pulsation in aeroplane hydraulic piping could induce fluid-construction vibration and lead to fatigue damage. It is impossible to find the error sensor's optimization location because of the pressure standing wave, and the pulsation attenuation effect is not perfect when adopting pulsation attenuation at single point. For this reason, a distributed active control method of fluid pulsation was presented. To avoid stationary point in all aviation states, several fluid pulsation actuators and error pressure sensors were placed along the piping. The second fluid pulsation produced by actuators can counteract the primary pulsation brought by aviation piston pump and make the mean pulsation of whole piping minimum when adopting adaptive feed- forward control and the filtered-X least mean square algorithm.

针对飞机液压能源管路系统中的周期性流体脉动诱发流固耦合振动，导致管路疲劳损伤的问题，针对管路中存在压力驻波特性，在采用单点消振时寻找误差传感器最佳布局位置困难而引起脉动抑制效果不理想的缺点，提出了一种分布式流体脉动主动控制方法，即沿管路不同位置布置多个主动消振阀和误差压力传感器，在任意飞行阶段，避开压力驻波点，以误差压力传感器的脉动测量值为控制目标，采用一种针对周期脉动主动控制的自适应前馈控制法和多通道自适应滤波－X LMS算法，调整控制器参数，使主动消振器产生的次级脉动与管路中的初始脉动相互抵消，达到整个管路中的平均流体脉动最小的效果。

Results show that FPS-TMD can effectively reduce the structural dynamic response. Under the sine wave, the response of top level decreased about 30%, under earthquake, the response decreased above10%, maximum to 25%. And the mean square root of the response decreased above20%, more effective than that of the peak point of structural response.

分析结果显示FPS-TMD能够有效地减小结构的动力反应，在正弦激励下顶层反应峰值的减小在30%左右；在地震激励下顶层反应峰值的减小在10%以上，最大达到25%。

A 9 -Bit square lattice gas model with temperature was introduced. We fulfilled an acoustic driver using Monte Carlo Method. Using this driver to generate plane waves, a standing sound wave was established in a two\|dimensional pipe.

引入带温度的 9- Bit正方形格子气自动机模型，利用MonteCarlo方法模拟声源并激发平面波，在二维谐振腔中建立了声驻波场。

Adopting a new self-consistent method, we calculate the energy levels and wave functions of symmetric double-square-quantum-well structures where the electronic density and the depletion lengths in the modulation-doped regions are determined self-consistently according to the properties of the materials and the growth conditions.

采用一种新的自洽方法计算了对称双量子阱的能级和波函数，其中电子密度、调制掺杂区电离层的厚度等参数是根据材料的性质、生长条件等自洽确定的。

In the production of various types of decorative panels, composite boards, transparent lighting board, wave board 2.6 million square meters, all kinds of FRP cable retaining tube 1600000 meters, all kinds of FRP process pipe, sand control, GWF Composite Pipe 2,600,000 meters, SMC molding FRP composite door 200,000 kg and all kinds of molded products, stainless steel water tanks FRP 10,000 cubic meters.

年生产各类装饰板、复合板、透明采光板、波形板260万平方米，各类FRP电缆护管160万米，各类FRP工艺管、夹砂管、GWF复合管260万米，SMC模压复合FRP门20万合及各类模压制品，不锈钢玻璃钢水箱10000立方米。

At present, the three cross-route Bureau Ltd. has more than 100 engineering and technical personnel and workers entering the construction of more than 10,000 square meters of living space construction have been completed, anti-wave block, Nanti sand have been built 100 m long.

目前，中交三航局有限公司已有100多名工程技术人员和工人进场施工，1万多平方米的施工生活用房已经建成，防波挡沙堤南堤已建成100米长。

Modulus of elasticities of five kinds of wood members including purlin on the ridge of the roof, square purlin, round purlin, beam, sprocket from Grand Hall of Golden tile, Kumbum Monastery located in Qinghai Province were measured by using stress wave method.

采用应力波测定仪FAKOPP对塔尔寺大金瓦殿的脊檩、檩、梁、承椽檩、房椽等五种木构件的动弹性模量进行了测定，结果表明应力波无损检测可以有效的测定残余木构件的力学强度，不同种类木构件弹性模量保持率与其承重作用大小相关。

According to the gap in the field,the effect of mutative skin temperature on objects' millimeter wave radiation temperature is studied. The radiation temperatures of various objects with different skin temperatures are measured by 3 mm DC Dicke radiometer.The result shows the change rules of radiation temperatures of objects with different emissivities are distinct.And the effect is more obvious as the higher emissivity.Based on measured data, temperature variation coefficients of various objects are calculated by the least square method.

针对目标表面温度实时变化引起毫米波辐射变化的规律尚未被研究的现状，使用3 mm直流Dicke式辐射计对不同表面温度条件下的目标辐射温度进行了测量，发现使用不同发射率材料的目标的辐射温度随表面温度变化的规律明显不同，材料发射率越高，目标辐射温度受表面温度的影响越大。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。