查询词典 variable-density system

This dissertation is engaged in increasing the efficiency of the variable speed variable pitch WPGS. The technical and operation characteristics of the system are analyzed and the control schemes are researched in theory and simulation. And then, the emulation of WPGS in lab is also explored in order to verify the affectivity of the control scheme.

本文以提高风力机的风能捕获效率为目的，以变速变桨距风电机组为研究对象，分析了其技术特点和运行特性，对其变速控制策略进行了深入的理论研究和仿真分析，并对其实验验证手段进行了探索。

With the new concept,the problem of variable structure control of 2D discrete system is transferred to the problem of seeking a sliding model with good sporting character and attractability. The concrete design schemes of the imitative sliding model and variable structure controller are also put forward. And the concrete expression of the time T in ε-neighborhood of reaching switch manifold is obtained. The difficulty of applying the existing methods to MIMO systems is overcome.

在新概念之下，将2D离散系统的变结构控制问题转化为寻找一个既具有良好的运动品质又具有吸引性的滑动模问题，给出了滑动模及变结构控制器的设计方案，并且获得了达到切换流形的ε领域的时间T的具体表达式，克服了已有方法难以应用到多输入—多输出系统上的困难。

It uses a uses the MSFlexgrid to enter the augmented matrix but its limit is 253 because I use a Byte variable to define the equations number so if you want to use it for a bigger Linear System you will have to change some variable definitions

它使用一个MSFlexgrid 来输入参数矩阵，参数个数最多是253个，因为我使用一个Byte 变量来定义方程的未知数的个数。所以如果你想在更大的线性系统中使用它，你将必须修改变量的定义。

They will be used in different situation in complex loop control; second, proposed an analysis method to compose multiple loops which have major control variable and auxiliary variable into a large system loop.

其分别适宜于不同情况下的复杂系统中较复杂回路的具体控制；其次，提出将复杂过程系统中主控变量及辅助变量所在的多个回路统一构成一个系统"大回路"的分析方法。

Short-term system load variation has apparently periodicity, the load is a variable that is influenced by many kind of factors, it can be subdivided into periodic basic load component and variable load component.

电力系统负荷变化具有明显的周期性，是一个受多种因素影响的量，可以将其分为周期性的基本负荷和受多种因素影响的变动负荷两部分。

Based on X-filtered LMS algorithm and -filtered LMS algorithm adaptive inverse control, we use a new variable step size LMS algorithm. Adding little computation, variable step size LMS algorithm can result in fast convergence speed and low residual error simultaneously. The adaptive feedback control can counteract the beginning error of the system. The adaptive disturbance canceler can best erase noises and disturbances.

在原来的X-滤波LMS算法自适应逆控制和-滤波LMS算法自适应逆控制方法的基础上，引入了新的变步长LMS算法，在计算量增加不多的前提下，能同时获得较快的收敛速度和较小的稳态误差；引入自适应的反馈补偿控制克服了被控系统的直流零频漂移，使控制系统在初开始工作阶段快速收敛；还引入自适应扰动消除器，它能最大限度的消除扰动。

Moreover, in order to decrease system's tracking error, the change rate of input variable is taken as a control variable, this strategy is suitable for a class of tracking control systems in which the input changes rapidly.

文中所采用的将输入变量的变化率作为控制变量来降低系统跟踪误差的方法，适用于一类输入变化较快的跟踪控制系统。

to reduce the impact of carrier frequency offset in ofdm system,this thesis designs a new carrier frequency offset estimation scheme for ofdm system.the carrier frequency offset estimation includes acquisition and tracking.we adopt variable step size adaptive algorithm.the acquisition range of the proposed algorithm is as large as one half of the overall signal bandwidth.through this method we can not only avoid the feedback by using forward error correction,but also reduce the times of complex multiplication in order to reduce the power consumption of the system.this algorithm not only has low complexity and fast convergence nut also can improve the demodulation performance of ofdm system.computer simulation illustrates the superior performance of the proposed algorithm with regard to estimation accuracy in both awgn channel and multi—path channel.

摘 要：为了减小正交频分复用系统受频率偏差的影响，在ofdm系统中设计了一种新的载波频偏估计算法。频偏估计包括跟踪和捕获两个阶段，文中采用变步长自适应算法来进行跟踪，这个跟踪算法的捕捉范围是整个信号带宽的一半。通过此方法，不但可以利用前向纠错的方式来避免反馈，而且可以缩减复数乘法的次数以降低计算复杂度和系统功耗。该方法运算复杂度低，并具有较好的收敛性，能改善odfm的解调性能。从计算机的仿真效果可以看出无论是在awgn信道上还是在多径信道上都表现出了卓越的性能。

According to induced response method, the expression in frequency domain of pressure response at the end of pipeline is derived using impulse response method and convolution theorem. The expression indicates that that transfer function is only related to the characteristics of pipeline system and the Fourier transform of flow variable only depends on the operating characteristics, and the pressure response in frequency domain is linear with the Fourier transform of flow variable.

基于激励响应法，应用脉冲响应方法和卷积定理得出了管道末端压力响应在频域中的表达式，此式表明：传递函数只与系统的特性相关，流量变量的傅立叶变换只与操作特性相关，且压力频域响应与流量变量的傅立叶变换为线形关系，根据此式在理论上能够得到管道泄漏点的重要信息。

A curve coordinate system which is suitable for variable height curved box-girder were established. The flexure, torsion and distortional warping displacement functions were established, and the strain-deformation equations were obtained, a spatial finite element analysis method of trapeziform cross section variable-curvature box-girder with vertical symmetrical axis was also presented.

建立适合于变高度曲线箱梁的曲线坐标系，推导了变曲率、变高度箱梁弯曲、翘曲扭转和畸变的位移方程和应变-位移关系式，提出了具有一个竖直对称轴的变高度变曲率曲线箱梁的薄壁曲梁空间分析有限元方法。

The concept of equivalent rotationally rigidity is offered and the formula of rotationally rigidity is obtained.

主要做了如下几个方面的工作：对伸臂位于顶部的单层框架—筒体模型进行分析，提出了等效转动约束的概念和转动约束刚度的表达式。

Male cats normally do not need aftercare with the exception of the night after the anesthetic.

男猫通常不需要善后除了晚上的麻醉。