控制变换

Secondly, by applying inverse Fourier integral transform to the displacement, and uniting the constitutive and geometrical equations, the analytical expression of stress in Laplace domain were derived. Thirdly, by defining dislocation density functions, the Cauchy singular integral equations were obtained according to the boundary condition and interface connection conditions, and the problem was reduced to algebraic equations by Chebyshev orthogonal polynomial. Based the these, the unknown coefficient of the algebraic equations can be solved by Schmidt method. Finally, the time response of dynamic stress intensity factor and energy release rate are obtained by inverse Laplace transform.

首先，利用积分变换方法，推导出粘弹性层的控制方程组；其次，引入位错密度函数，并结合边界条件和界面连接条件，导出反映裂纹尖端奇异性的Cauchy型奇异积分方程组，然后，应用Chebyshev正交多项式化奇异积分方程组为代数方程组，并采用Schmidt方法对其数值求解，最后，经过Laplace逆变换，求得动态应力强度因子和能量释放率的时间响应。

Based on the high frequency power amplifier,a class E resonant high frequency DC/DC and a phase-shifted control strategy are proposed in this paper,the converter based on the idea can heighten switching frequency,reduce the loss of the system,widen the range of output.

以高频功率放大器为基础，提出了一种超高频E类谐振DC/DC变换器的移相控制策略，基于这种思想的变换器可以提高开关频率，降低系统损耗，拓宽输出范围。

The new method of solving the hydraulic fracture moveable boundary problem by use of the method of the conformal transformation and body-fitted coordinate is put forward; according to the law of continuation, the transformation from the control equation in the physical plane to the calculation plane is completed, and two dimensional fluid field numerical simulation in the fracture is also finished.

提出了利用保角变换和贴体坐标变换处理水力裂缝动态边界问题的新方法，根据链导法则完成了物理域控制方程向计算域平面的转换，实现了二维流场的数值模拟； 5。

Firstly, counterchanges the control signal coordinate, behind, forecasts and filters the waves according to the α-β-γ filter arithmetic, finally, reverts the forecasting result coordinate, and inputs the forecasting result...

根据复合控制原理，对控制信号首先进行坐标变换，然后依据α-β-γ滤波算法进行预测和滤波，最后，对预测结果进行坐标还原，将预测值加到伺服控制的输入端。

Some technical problems arose during the debugging of the accelerator. The ion source did not produce arc. The accelerator tube cracked. The control system was out of order. The transporting capacity of the charge belt degraded. The corresponding reasons were analyzed and some measures were adopted to solve the problems. The drawing voltage was raised to its predetermined position after the ion source produced arc and should be reduced to zero before turning off the accelerator. Transition flange was lathed and the accelerator tube was re-assembled. The control equipment at high voltage was shielded. TVS diodes were installed at the input and output ends.

调试中出现了离子源不起弧、加速管破裂、控制系统失灵和输电带输电能力降低等技术问题，分析了出现这些问题的原因，然后分别采取了相应的措施加以解决：变换工作流程，在每次关机前先把引出电压降为零，开机时等离子源起弧后再把引出电压升到预定值；对过渡法兰进行车加工，重新封装；对高压端的控制设备采取屏蔽措施，在输入、输出端使用TVS二极管，对控制软件进行抗干扰设计；对绝缘气体进行循环干燥等。

Aiming at realizing embeddedARM control system on musical fountain, the design of software and hardware of this system was completed by Linux operating system with the frame of SAMSUNGs S3C2440 microprocessor. After extracting the sounds volume and tonality by dealing with the music signal in advance, the musical fountains spraying height, light and shape of water were controlled efficiently by embedded system.

为实现基于嵌入式ARM的音乐喷泉控制系统，采用三星公司以S3C2440微处理器为核心的架构，以Linux操作系统为平台，完成了音乐喷泉控制系统的软、硬件设计，并通过对音乐信号的预处理提取声音中的音量和音调，利用嵌入式系统有效地控制了音乐喷泉的喷水高度、灯光和水型变换。

Lightened on the turbine valve controller designed with feedback linearization theory and introduced nonlinear tracking-differentiator, a novel nonlinear PID valve controller was proposed. This controller can fit not only to plant with some model error and random disturbance in variable, but also to the variety of the structure and operating conditions of power system. The transient and dynamic characters of the controller are both satisfactory when big and small disturbances added. The good performance, wide stable margin and heavy robustness of the valve controller proved that it is a great practical application to enhance the stability of power system.

结合反馈线性化法汽轮发电机组的汽门控制研究成果，引入非线性跟踪微分器和非线性度变换控制，进行了发电机组的非线性PID汽门控制器设计，该控制器不仅能适应一定的系统模型误差与变量的不确定性干扰，而且对于电网结构和运行工况的变化有着较强的适应能力，在受大、小扰动的情况下，呈现了较好的暂态特性和动态品质，具有较好的控制品质、较高的稳定裕度和较强的鲁棒性能，有利于进一步改善电力系统的稳定性，显示了其较强的实用性。

And then, they, how to upgrade the technical capability of inverter welding power supply by bringing the dominance of digital control into play fully, and how to realize the soft-switching of power semiconductor devices in the full-load range of inverter welding power supply by making the digital control cooperation with power converter closely, are set forth.

在介绍数字化控制焊接逆变电源内涵和发展历程的基础上，阐述了如何充分发挥数字化控制的优势，全面提升焊接逆变电源的工艺性能，以及如何通过数字化控制和功率变换电路的紧密配合，实现焊接逆变电源的全负载范围功率器件软开关。

Through the analysis of the work principle of three phases voltage resource PWM converter, set up the low and high mathematic models, deduce the restriction equations about grid voltage, grid current, modulation voltage and the DC output voltage and the calculation equations of the AC-side inductance and the DC-side capacitance. There are two control strategies are adopted: Predicted current control strategy and voltage-current two closed-loop control strategy, and give a comparison by theory and practice.

通过分析三相电压源型PWM变换器的工作原理，分别分析了低频和高频数学模型，并推导出了交流侧电压电流、调制电压、直流侧电压之间的数学约束关系以及交流侧电感和直流支撑电容参数的选取依据公式；分析对比了两种控制策略：预测电流控制和电压电流双闭环控制并加以实验验证；同时采用了负载电流前馈补偿和本文提出的一种基于专家系统的神经元新型智能PI控制器两种方法大大提高了整个系统的动态响应性能，并在仿真和实验中加以验证，这也是本文研究的重点内容之一。

Using coder ,D/A transducer and frequency converting speed regulator makes up the automatic control system of rope machine's wire ranging apparatus.

利用编码器、D/A变换器、变频调速装置，构成制绳机排线自动控制系统，将原间歇位移随动控制系统改为连续位移自动控制系统，可以解决制绳机钢丝绳收线排布不均的问

Chrysanthemum of 10 thousand birthday is lax to edaphic requirement, with the arenaceous qualitative loam with fecund, good drainage had better.

万寿菊对土壤要求不严，以肥沃。排水良好的砂质壤土为好。

He unstepped the mast and furled the sail and tied it.

他拔下桅杆，把帆卷起，系住。