查询词典 sound of the wind

GXF-I conduit is inclined sort fan engine order: 2#- 8# wind force: 200 - 25000m3/h total pressure: 54 - 1200Pa characteristic: Use impeller of canister of bosomy form wind, cone-shaped hub, wind pressure tall, wind force big, noise province of report of low, bad news, structure is compact wait for an advantage, horizontal, vertical is installed all but, most apply to straight conduit and pressurization to send a platoon wind, material can use glass reinforced plastics or steel is made, also can make a place with a draught of housetop type, pass in and out can add set muffle application: Industry and civil architectural send a wind the system.

最新供应专业生产供应管道斜流风机。 GXF-I通道斜流风机机号：2#－8#风力：200－25000m3/h全压：54－1200Pa特征：使用鼓型风筒、锥型轮毂叶轮，风压高、风力大、噪声低、耗电省、构架拮据等优势，卧式、立式装置都可以，最适用在直通道和加压送排风，材料可用玻璃钢或者钢制造，亦可作成屋子顶式、进岀风口可加设消音器运用：工业制造业和民用健造的送排风体系。

There were 8 groups and each groups had 8 cows in the experiment.groups A was the positive group, be feeded basic dietary and in the normal environment; groups B was basic dietary and in the improved environment ; Group C was feeded with basic dietary and NaHCO_3(120g/d/head) and Mg0(50g/d/head) and KCl(180g/d/head), in the environment with no spray and no wind; Group I is feeded with basic dietary and NaHCO_3 (120g/d/head) and MgO(50g/d/head) and KC1 (180g/d/head) and in the another environment with spray and wind; Group E was feeded,with basic dietary and traditional druggery additive in the environment with no spray and no wind; Group F was feeded with basic dietary and traditional druggery additive in the environment with spray and wind;Group G was feeded with basic dietary and NaHCO_3 (120g/d/head) and MgO(50g/d/head) and KCl (180g/d/head) and traditional druggery additive in the environment with no spray and wind; Group H was feeded with basic dietary and NaHCO_3( 120g/d/head ) and Mg0(50g/d/head) and KCl(180g/d/head) and traditional druggery additive in the environment with spray and wind.

试验分8个处理，每个处理8头奶牛，A处理为对照组，喂以基础日粮，处于常规环境(未喷雾，未机械吹风，下同)，B组为喂以基础日粮，处于改善环境：C组为基础日粮+NaHCO_3(120克/头。日)+MgO(50克/头。日)+KCl(180克/头。日)，处于常规环境：D组为基础日粮+NaHCO_3(120克/头。日)+MgO(50克/头。日)+KCl(180克/头。日)，处于改善环境；E组为基础日粮+中草药添加剂组，处于常规环境；F组为基础日粮+中草药添加剂组，处于改善环境；G组为基础日粮+NaHCO_3(120克/头。日)+MgO(50克/头。日)+KCl(180克/头。日)+中草药添加剂组，处于常规环境；H组为基础日粮+NaHCO_3(120克/头。日)+MgO(50克/头。日)+KCl(180克/头。日)+中草药添加剂组，处于改善环境。

The paper analyzes the shortage of traditional roadway measuring wind method,and by theoritical calculation of measurement,the wind amount is tested,and the roadway fixed central point method of wind measurement and the roadway s average wind velocity fixed-point method of wind measurement are proposed,and which solve the problem of low wind velocity and low credibility well.

分析传统井巷测风方法的不足，并通过风量测定的理论计算和对现场风量进行实际验证，提出了井巷中心点定点测风法和井巷平均风速点定点测风法，较好地解决了当前测定风速慢、可靠性差的问题。

The authors discuss a new numerical simulation method of the downburst wind loads on the basis of the previous research. Firstly, the wind speed is expressed as the sum of an instantaneous mean wind speed and an amplitude-modulating non-stationary fluctuating wind speed. Secondly, a new method based on the modified Osegguera and Bowles/Vicroy model to simulate the mean wind is presented and the fluctuating wind is simulated by a modified spectral representation method.

在将下击暴流风速表达为时变的平均风速和调制的非平稳脉动风速之和的前提下，本文采用基于改进的OBV模型Oseguera and Bowles/Vi-croy(OBV的方法来模拟平均风速，其平均风速直接由改进的OBV模型表达，而不同于已往研究中将平均风速表达为竖向风剖面与时间函数的乘积，并采用结合快速傅里叶变化的谐波叠加法来模拟调制的非平稳脉动风速。

AR model in linear filter theory is adopted to simulate pulsant wind. Combined with some typical cable-membrane structures, research on self-vibration of the structure has been conducted. Based on the previous work, the influence caused by the vertical wind component on the membrane roofs has been analyzed in time domain. It includes the vibration laws of the structure under separate horizontal wind component, separate vertical wind component and the collective horizontal wind component and vertical wind component. Significant conclusions have been drawn from the analysis.

然后本文采用线性滤波器法中的AR模型对风速场进行了模拟；之后又结合典型的张拉索膜结构研究了膜结构的自振特性；在此基础上，本文研究了索膜结构在竖向脉动风影响下的风振响应特性，其中分别研究了张拉索膜结构在单独水平风，单独竖向风以及水平风和竖向风共同作用下的振动规律，得出了有关重要结论。

To get the biggest power coefficient at various of wind speed, put out the argument of controlling wind turbine according to the wind pressure which act on the wind wheel swept area. Design and make a wind turbine which can adjust pitch angle of oar leaves through various of wind speed, and make experiment of characteristic.

1引盲 传统的风力机优化设计方法是以桨叶各截面在设计风速处具有最大的功率系数为目标，设计是针对事先确定的一个设计风速进行的，风力机只能在设计风速点处获得最大功率系数。

This paper presents a wind vane sensors without the use of cases, combining with gyroscopes and hill-climbing algorithm to control the yaw institutions, can accurately capture the wind direction signal, rapid-conditioning the cabin of the deflection angle, so that wind generators wind wheel normal direction of the wind direction and change is always consistent for maximum capture of wind energy control strategies.

针对风力发电机组的风向变化绝对值小于15°的风能捕获率问题，提出一种在不使用风向标传感器的情况下，采用陀螺仪和爬山算法相结合的方法来控制偏航机构，能够准确的采集到风向信号，快速调节机舱的偏转角度，使风力发电机风轮法线方向与变化的风向始终保持一致，实现最大捕获风能的控制策略。

The complete wind turbine speed control firstly proposed here also improves the tracking effect of wind turbine rotating speed to variable wind speed. Wind turbine rotating speed synchronized power observer compensates the power ripple of wind turbine resulted in inverter dead time. A low pass filter used at the output of MPPT controller smoothes the speed reference, which makes the rotating speed of wind turbine more stable.

本文首次提出的变转速扰动的MPPT控制提高了风车最大功率点追踪的快速性和稳定性，风车完全转速控制提高了风车转速对变动风速的跟踪效果，转速同步风车功率观测法消除了逆变器死区所造成的风车功率波动的影响，带有低通滤波器的MPPT控制器使得风车的转速更加趋于平稳。

"Subaudible, low frequency sound and infrasound from wind turbines do not present a risk to human health" and "a major cause of concern about wind turbine sound is its fluctuating nature; some may find this sound annoying, a reaction that depends primarily on personal characteristics as opposed to the intensity of the sound level."

"低频声和风力发电机发出的声音都不会对人类健康造成伤害""人们关注风力发电机声音最主要的方面是它的波动性，有些人很讨厌这种声音。这种反应主要取决于每个人的性格原因，而不是声音的强弱度。"

According to the studied results at present, the studied objects are mainly thin plate and beam about sound radiation mode, a method computed sound radiation mode of complex structure is presented in this dissertation, according to the results of the previous two chapter, a theoretical method to solve acoustical radiation mode and acoustical radiation efficiency of complex structure by boundary element method and acoustical radiation theory is posed, the acoustical radiation power is expressed as a Hermitian quadratic form, while the radiation modes is determined by general eigenvalue decomposing, and then the radiation efficiency is computed via the orthodoxy of radiation modes with regard to impedance matrix and average velocity matrix; lastly, the validity of the method is proved by pulsating sphere and radiating cube with analytical results. According to results of the form three chapter, the structure sound radiation sensitivity is studied in detail, the sound radiation power of structure can be expressed as positive Hermitian quadratic form, the sound radiation sensitivity can be expressed as two parts by partial differential with respect to design variable, which are sensitivity of boundary velocity and impedance matrix, combined with the theory of FEM and BEM, the structure sound radiation can be translated to the analysis of structure dynamic sensitivity and impedance matrix sensitivity. The theory posted in this dissertation is tested by the FEM software ANSYS and the software AAS programmed by author.

在前几章的基础上，通过结构声辐射的模态理论对结构的声辐射的机理进行了深入地探讨，针对目前声辐射模态的研究对象主要是简单的板和梁类结构，提出了一种计算复杂结构声辐射模态的方法，利用前两章研究所得的结论，将边界元方法与广义特征值的理论结合起来研究了复杂结构的声辐射模态与声辐射效率，先将结构的声辐射功率表示为一个正定的厄米特二(来源：ABb7C论文0909网www.abclunwen.com)次型，运用广义特征值分解求解了复杂结构的声辐射模态，然后利用声辐射模态关于阻抗矩阵与均方速度耦合矩阵的正交性，求解了复杂结构的声辐射效率，最后用具有解析解的脉动球与辐射立方体验证了该方法的有效性。

The work of this paper is as follows: 1. Looking back the progressing history of the linear motor, introducing the features of the elevator driven by linear induction motor, radicating the topic of this paper "the digital frequency variable control of the elevator bi-side direct driven by linear induction motor". The research of this paper covers the conventional VVVF control, space vector based VVVF control, vector control and DTC.

本文主要开展了以下几个方面的工作： 1 回顾了直线电机发展历史，电机的驱动技术演变，特别是针对直线电机的驱动，简要介绍了直线感应电机驱动电梯的优点和不同结构类型，对传统的v／f控制，基于空间矢量法的v／f控制，矢量控制，和基于电压空间矢量的直接转矩控制进行了比较，确立了本课题的研究主题：直线感应电机双边直推式驱动电梯的全数字变频控制。

The article combines with the treatment of a superficial civil air defense work to introduce how the grouting method to improve the performance of the backfill soil.

文章从治理漂浮人防工事的角度提出了注浆技术在改善回填土性质方面的应用，并详细阐述了注浆技术的施工流程。