振荡的

Based on the analysis of the mechanism of robot manipulators, a trajectory tracking controlling research model is first built up with ADAMS, and its mathematical model is formulated through the study of robot kinematics and dynamics. After the modeling errors are analyzed in practical robotic systems, a conception of centralized error is brought forward according to the theory of weighting functions. In the case of modeling errors' exist, the robotic uncertain model is derived by introducing an auxiliary control variable into inverse dynamic analysis. The control strategy of robust exponential convergence is applied to the robotic uncertain model, the applicable conditions and the applicable controller with this application are presented. The stable control effect under three main model uncertainties (parametric errors, joint disturbs, joint frictions) are systematically studied on the previously built research model. The problems of robust exponential convergence controller which often results in unstable output and so produces a large relative error when the input trajectory is in a small range are resolved by adjusting the control parameters based on the controller's structure.

本文在机械手的机械结构分析基础上，利用ADAMS建立了用于机械手轨线跟踪控制研究的机械手模型；通过对机器人运动学和动力学问题的研究，建立了机械手研究的数学模型；分析了机器人系统中模型误差的主要来源，根据加权函数法分析，提出了模型集中误差的概念；在存有模型误差的情况下，采用逆动力学结构并引入辅助控制量，由机器人误差模型推导了机器人非确定性模型；提出了采用鲁棒指数收敛法对上述机器人非确定性模型进行鲁棒镇定的控制策略，并给出了对机器人进行鲁棒指数收敛控制时系统不确定因素应满足的匹配条件；针对机械手研究模型，深入研究了鲁棒指数收敛控制器对机器人系统中常见的模型参数误差、关节扰动、关节摩擦等不确定因素的镇定控制效果；针对鲁棒指数收敛控制器易产生控制量振荡的问题以及在小范围内系统轨线跟踪的稳态误差过大问题，本文分别提出了基于控制器结构的控制参数调整法和基于轨线跟踪范围大小的控制参数分段切换法。

A series of theoretical and experimental studies on the microstrip patch antennas with dielectric superstrates is carried out systematically. Firstly, a comprehensive survey of the microstrip antenna technology and its theories are presented. Then, two analysis techniques, named as the spectral domain Green's function method and the spectral domain integral equation method are developed. The SDGF method is a simplified analysis technique, which takes advantage of the spectral domain immittance approach to find the dyadic Green's function for the stratified media, and obtains the complete closed-form formulas for radiation patterns, directivity, efficiency, gain etc. Some interesting calculated results are presented. The SDIE method is capable of determining resonant frequency, radiation characteristics, input impedance etc, for the covered microstrip patch antennas. Comparing with other full-wave analyses it reduced computation and mathematical labour remarkably. The singularities near the pole location of the surface-wave modes and the difficulty of the integral computation over infinite range of oscillating integrands are dealt with actively and documented well. Results predicted by the SDIE method agree extremely well with our experimental results for resonant frequencies of various superstrates. The superstrate effects on impedance and radiation characteristics also have been investigated experimentally so that the gap due to lack of measured data and computed results for multi-layered superstrate has been filled to some degrees and two useful observations have been achieved for weakening the resonant frequency shift and optimizing the microstrip antenna gain. As a meaningful application, the design and analysis of a 4×4 patch array are introduced.

实用微带天线普遍加介质覆盖层来防护热，物理损伤和环境影响，也可能在飞行或严酷气候条件下自然形成覆盖层本论文对带介质覆盖层的微带贴片天线系统地作了一系列理论和实验研究首先，对微带天线技术和理论作了全面的综述然后，发展了两种分析方法，称为谱域格林函数法和谱域积分方程法SDGF法是一种简化的分析技术，它利用谱域导抗法来求得分层媒质的并矢格林函数，并得出方向图、方向性系数、增益等参数的完整的闭式公式，给出了一些令人感兴趣的计算结果SDIE法能确定介质覆盖微带天线的谐振频率、辐射特性和输入阻抗等与其它全波分析方法相比，它明显减小了计算量和数学工作量已有效地处理了表面波模极点附近的奇异性和对振荡的被积函数的无限区间积分计算的困难对于不同覆盖层情况下的谐振频率，由SDIE法所预示的结果与我们的实验结果吻合得很好对于覆盖层对阻抗和辐射特性的影响也已作了实验研究这在某种程度上填补了缺少实验数据和计算结果之间的间隙，并得出了缓解谐振频率偏移和优化天线增益的两点有用的结论作为有意义的应用，介绍了一个4×4元矩形贴片天线阵的设计和分析。

In the numerical study, the governing equations of flow and heat transfer in 3 —D body—fitted curvilinear coordinate system being automaticly generated with TTM method were deduced by means of vector and tensor analysis. These equations were dliscreted with nonstaggered grids providing relative elimilating method for the pressure oscillation was domonstrated.

在数值分析中，借助于矢量理论和张量分析，导出了具有普遍意义的三维任意曲线坐标系下的流动传热控制方程，并利于TTM方法生成了计算域的贴体曲线坐标网格；在数值离散过程中，尝试了用非交错网格离散的方法并解决了压力场振荡的抑制问题；运用附面层理论，阐述了壁面函数法在三维任意曲线坐标系上的应用。

In case of the hag paralysis sleep disorder the person experiences constant hypnagogic hallucinations ie when the person is oscillating between the sleep and wake states.

在案件的女巫瘫痪睡眠障碍的人的经验不断hypnagogic幻觉即是振荡的人之间的睡眠和唤醒的国家。

matlab sps is used to build a simulink model of single-machine infinite-bus system, and based on the simulink model, simulation on effect of pss suppressing small disturbances low frequency oscillation is carried on, and some methods of improving power system transient stability are simulated, including avr and pss, short circuit cleared rapidly, fault current limiter and single-phase auto reclose. the study unifies the simulink model to realize matlab and vb seamless integration using the activex technology, and demonstrated the matlab simulation result with the vb contact surface. this method of matlab and vb integration can make up the matlab contact surface unfriendly flaw and offers a reference for the design for cai of power system analysis course.

运用matlab电力系统仿真模块集sps构建了单机—无穷大系统simulink模型，对电力系统稳定器抑制电力系统小扰动低频振荡的效果进行了仿真；对提高电力系统大扰动功角稳定性的措施，如自动电压调节器及电力系统稳定器、快速切除故障、故障限流器、自动重合闸等手段的使用效果进行了仿真验证；并结合单机—无穷大系统的simulink模型运用activex 技术实现sps与vb的无缝集成，将sps的仿真结果用vb界面显示，较好地弥补了matlab用户界面不友善的缺陷，为《电力系统分析》课程进行cai设计提供了思路。

Thus by using longer crystal and focused pump beam in OPA or OPO, the gain of amplification can be increased and oscillation threshold be reduced.

本文从理论上和实验上证实，OBNC对OPA和OPO参量作用有特别重要的意义，它可以使泵光束和信号光束在非线性晶体中实现最大的交叠并允许泵光束有较大的发散度，从而可以通过加长非线性晶体的长度或会聚泵光以增加参量作用的增益和降低振荡的阈值。

Difficulties existing in testing of nine carcinogenic dyes tuffs are analyzed,an innovative testing method is put forward as follows:using methol to extract the 9 dyes under the conditions of ultrasonic wave oscillation at 70 ℃,the extraction is separated by HPLC/DAD method.

分析了已知9种致癌染料检测中存在的困难，选择用甲醇作为萃取剂对这9种致癌染料在70℃、超声波振荡的条件下进行萃取，采用HPLC/DAD法对萃取液进行分离分析，讨论了试验中应注意的事项，如试剂、标准溶液的确定、仪器的选用、测试步骤的优化等。

In our study, multiple temperature-independent points and accompanying oscillations are observed in the longitudinal resistivity between the low-field insulator and the quantum Hall liquid. The amplitudes of these oscillations can be well described by conventional Shubnikov-de Haas theory, and our experimental results therefore support the existence of an intermediate metallic regime between the low-field insulator and quantum Hall liquid.

在此研究中，我们发现在低场的绝缘态与高场的量子霍耳态之间，纵向电阻率有多个不随温度变化的交点，而此交点所在的位置与其所伴随振荡的振幅可以利用Shubnikov-de Haas 理论解释，因此由我们的实验结果可以看出，在低场绝缘态与高场量子霍耳液体态之间，的确存在一个过渡的金属态。

A novel quasi-constant frequency hysteresis PWM control approach is presented in this paper. Frequency feedback is introduced in hysteresis current control to stabilize switching frequency. Comparing with the common used constant frequency current mode control, the new approach has better stability, faster transient and higher precision, as well as elimination of sub-harmonic oscillation.

摘 要：本文提出了一种新的准固定频率滞环PWM电流控制方法，该方法在滞环电流控制的基础上，引入频率反馈控制，使开关频率基本固定，解决了目前广泛使用的固定频率电流控制方法具有的次谐波振荡的问题，并且具有稳定性好、相应速度快、控制精度高的优点。

According to the process of the mutual reaction of the population number at each energy level of the un-equilibrium mixed gases flowing in flow laser and the intensive emission reaching the stable oscillation, and the numerical simulated calculation results of the corresponding 3-dimensional distribution states, the simplified calculation formulae of the basic properties of the corresponding oscillator and amplifier are developed.

根据流动激光腔中流动的非平衡混合气体各能态布居数和强辐射相互作用达到稳定振荡的过程和相应的三维分布状态的数值模拟计算结果，发展了相应的振荡器和放大器基本特性的简化计算公式。

And Pharaoh spoke to Joseph, saying, Your father and your brothers have come to you.

47：5 法老对约瑟说，你父亲和你弟兄们到你这里来了。

Additionally, the approximate flattening of surface strip using lines linking midpoints on perpendicular lines between geodesic curves and the unconditional extreme value method are discussed.

提出了用测地线方程、曲面上两点间短程线来计算膜结构曲面测地线的方法，同时，采用测地线间垂线的中点连线和用无约束极值法进行空间条状曲面近似展开的分析。