研究了无穷边界的二阶椭圆问题，探讨了将其转化为一阶系统的最小二乘有限元逼近方法。
A least-squares mixed finite element methods for the first-order system formulation of second-order elliptic problems and a formulation for the infinite boundary conditions are presented.
l在过程和步骤已经确定的给定系统中，一阶变化是个变异，它使系统本身相对的不变。
First-order change is a variation in the way processes and procedures have been done in a given system, leaving the system itself relatively unchanged.
对光学系统输出刀口像的一阶导数做傅里叶变换，可以得到该系统的光学传递函数（OTF）。
The OTF (Optical Transfer Function) of an optical system can be evaluated by the Fourier Transform of the first derivative of the optical image of an knife-edge (object).
一阶加纯滞后或二阶加纯滞后，并且提出了时滞系统的模型参考自适应控制的设计方法。
And a design method of model reference adaptive control for system with pure lag is presented.
本文给出了连续系统中计算二次型性能函数对反馈系数阵的一阶和二阶灵敏度的全套公式。
A set of formulas for the computation of quadratic performance function associating with first and second-order sensitivities of feedback coefficient matrix is given in this paper.
介绍了PF C的基本原理，推导了一阶加纯滞后系统PF C算法。
The basic principles of PFC are introduced, and PFC algorithm for first-order plus dead-time system is delivered.
应用灰色系统理论，由油井重复压裂前的递减产量，生成相应的一阶累加序列，由累加序列建立了灰色预测模型GM (1,1)。
A grey predicting model of GM (1, 1) can be established with the accumulated sequence generated by the oil well decline rate before refracturing according to the theory of grey system.
本文提出了海洋平台结构系统疲劳可靠性分析的一阶二次矩方法。
A first order second moment formulation for systems fatigue reliability assessment of offshore structures is presented.
通过形式化描述和分析CSCM机制的系统模型和运行模型，证明了CSCM具有一阶线性的消息复杂度和收敛时间。
By formalizing description of system model and running model of CSCM mechanism, the usability and extensibility of the system is given, and the message complexity and convergence time is proved.
在单机无穷大系统中，运用小扰动分析法推导出了PSVC的一阶惯性模型。
In a single generator infinite system, the one order inertia model of PSVC is derived with the small disturbance method.
笔者指出，当入射引力波和高斯束不同频率时，高斯束谐振系统产生的一阶扰动光子流没有观测效应。
This paper points out that the first-order perturbation photon flux produced by this system has not observed effect when GWs is different from frequency of Gaussian beam.
第一阶模态振型相对均值系统的变化很小。一般地，结构参数的随机变异对模态振型均值的影响大于对模态频率、模态阻尼比均值的影响。
In general, the variation of structure parameters has more effect on the mean values of mode than those of modal frequencies and modal damping ratios.
从广义惠更斯-菲涅耳衍射积分出发，导出了洛伦兹光束通过一阶轴对称光学系统传输变换的解析公式。
Based on the generalized Huygens-Fresnel diffraction integral, the analytic propagation expressions for Lorentz beams passing through first-order axisymmetric optical system are derived.
基于一阶比例-积分控制器分析了弱光61单元自适应光学系统的控制特性。
The control characteristics of low light level 61 element adaptive optical system are analyzed based on an one order proportional integral controller.
然后根据频域分析法，得出了整流器的一阶惯性模型，并推导出系统的频域控制模型。
Then, according to the frequency domain control method, we educed the rectifier's one-order inertia model and deduced the system's frequency domain control model.
从预测模型、反馈校正和优化控制三方面对预测函数控制基本原理进行了系统的阐述并针对一阶加纯滞后对象推导了单变量预测函数控制的基本算法。
The principle of PFC is introduced from three aspects: predictive model, error compensation and optimal algorithm. The basic PFC algorithm for first-order plus time delay system is developed.
结果表明，由简单的一阶动态模糊控制器构成的控制系统，性能明显优于传统的静态模糊控制器构成的相应系统。
The results show that the performance of the control systems with the first-order dynamic fuzzy controller is much better than that with the traditional static fuzzy controller.
隧道通风过程可近似认为是一个一阶时滞系统，系统采用自整定模糊pid对隧道管网的风压进行实时控制。
Tunnel ventilation process is approximately a system of time lag of first order, real time control of wind pressure in tunnel pipe is adopted self-tuning fuzzy PID.
本文探讨了一阶纯滞后系统补偿的一种算法。
An algorithm for the compensation of a first order pure lag system is discussed in this paper.
由于供水过程可近似认为是一个一阶时滞系统，系统采用了自整定模糊pid对管网的压力进行实时控制。
The water supply process is approximately a system of time lag of first order, real time control of pressure in pipe is adopted self-tuning fuzzy PID.
这一结果可以用于证明一阶逻辑形式系统和我们所提出的广义反驳方法的完备性。
This result can be used to prove the completeness theorems of first order logic system and the universal refutation method proposed by us.
本文把液压伺服系统作四阶系统，跟随一阶参考模型，提出了一种新的高阶对象和低阶模型的MRACS 的方法。
This paper puts forward a new MRACS method using low order model, i. e. the fourth order hydraulic servo system following the first order reference model.
一阶谓词逻辑是现代逻辑中最为经典的演算系统。
Predicate logic of first order is the most classical calculation system in modern logic.
在一定加热功率下，正弦管能有效抑制系统产生的二阶谐波，提高一阶压力波动幅值并降低加热块温度。
The experiment result showed that sinusoidal tube can effectively inhibit second order harmonic mode, increase first order pressure amplitude and lower down heating block temperature.
我们也能使用一阶时态逻辑，为各种研究领域建立一些特定的形式系统。
We may also use the first-order temporal logic to set some specific formal systems for various fields of studies.
最后，根据所建模型的映射关系计算系统输出对输入参数的一阶灵敏度矩阵，对模型进行灵敏度分析。
Finally, the sensitivity analysis was carried out by calculating the first-order sensitivity matrix according to the mapping relationship between the output and the input of the system.
磁悬浮控制力矩陀螺(CMG)中转子一阶弹性模态自激振动是影响磁悬浮高速转子系统稳定性的关键因素之一。
In magnetically suspended control moment gyroscope (CMG), self-excited vibration of high-speed rotor is one of principal factor which effects stability of active magnetic bearing (AMB) system.
在损耗调制的情况下，系统变化前后的阈值载流子密度不同，被忽略的二阶小量可能会达到与一阶小量可比拟的程度。
For a loss modulation where the threshold carrier density may change, the neglected term may become comparable to the retained first order small quantity.
不忽略舵系统的动态特性，假设舵系统具有一阶动态特性。
In this case, the dynamic characteristic of the rudder cann't be ignored.
不忽略舵系统的动态特性，假设舵系统具有一阶动态特性。
In this case, the dynamic characteristic of the rudder cann't be ignored.
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