模方程

This paper, with the analysis of the propagation characteristics in a lossy cylindrical waveguide and using small-signal theoretical dispersion relation, presents study on the device stability with influence of the absolute instability and the backward wave oscillation in TE01-mode lossy dielectric-load gyrotron traveling wave amplifier.

摘要该文从分析损耗介质加载金属圆波导中电磁波传输特性出发，应用回旋行波管放大器小信号色散方程，研究损耗介质加载结构TE01模回旋行波管放大器绝对不稳定性振荡和回旋返波振荡对器件稳定性的影响。

The absolute/convective instability of incompressible swirling flows and the temporalinstability of compressible swirling flows have been fully explored, whereas the absolute/convectiveinstability of compressible swirling fl.

从N－S方程出发，通过正则模方法，研究了超声速尾涡的绝对／对流不稳定性性质。

It was proved that the existence of an absorbing set and a global finite dimensional attractor which is compact, connected in the function space for the high-frequency modes coupled two Ginzburg-Landau equations.

利用了无穷维动力系统理论，证明了两个高频模态耦合的Ginzburg-Landau方程在函数空间中存在吸引域，因而存在连通的、有限维的紧的整体吸引子。

The basic approach of protecting people from being hurt or killed in an accident is to improve crashworthiness of vehicles. This paper starts with discussing theories and methods for vehicle passive safety design, which included experiential methods, analytic methods, multi-body dynamics methods, crash test methods and the finite element method. Emphasis will be paid to the basic FEM theories and algorithms of impact problems. Topics discussed include the governing equation, element discretization, hourglass control, time integration, material model, shell element algorithms and contact-impact algorithms. For more reliable simulation results, this paper then conducts study on how to accurately get material model parameters by combining the FEM method with experimental method, and develops relevant material test machine and parameter calculating software. Based on that, basic typical impact simulation and test validation study are conducted. On the basis of the above work, the paper studies the thin-shell structures'crashworthiness, which was affected by the following factors: spot-weld features, shell thickness, cross-section and pre-deformation. As to vehicle parts'crashworthiness, the paper conducts simulation study of designing energy-absorbing steering system and adaptive airbag system. A practical energy-absorbing steering wheel is designed as an example. In further depth research, the paper suggests several inverse quantificational methods for vehicle crashworthiness design based on the ideal crash characteristics. The above theories and methods are applied with good results through several practical vehicles' crashworthiness design and improvement.

文中对汽车碰撞安全性的设计理论和方法进行了归类和总结，其中包括经验法、解析法、多刚体动力学法、试验法以及有限元方法等；重点介绍了碰撞有限元法的基本理论和有关算法，涉及到有限元求解控制方程、单元离散、沙漏模态控制、时间积分、材料模型和应力修正、薄壳单元算法以及接触碰撞界面算法等，探讨了有限元计算中的材料模型参数获取技术，开发了相应的材料试验装置及材料模型参数反求软件，在此基础上进行了基本的碰撞仿真算例和试验对比研究；文中通过应用有限元方法研究了薄壁构件的碰撞吸能特性，指出了设计薄壁吸能构件时需要考虑的几个主要影响因素，即焊点、壁厚、横截面和预变形等；在关于车辆部件的碰撞安全性能设计中进行了吸能转向机构和自适应安全气囊的仿真研究，提出了吸能转向机构和自适应安全气囊的仿真研究方法；文中最后探讨了整车碰撞性能的设计与改进方法，提出了以理想碰撞特性为目标，采用分段加速度或者根据碰撞时间进行设计的反推设计法、部件吸能仿真优化设计法等量化设计方法，并通过综合应用文中所讨论的相关技术进行了整车碰撞性能的设计与改进实例研究，所选定的车型是大众化的普通轿车和碰撞安全性基础较差的微型面包车，研究结果表明，本文所提出的设计与改进方法是适用而有效的，具有重要的工程实用意义和价值。

A character-codes model based pattern recognition method by using amplitude data of targets frequency response is proposed after the establishment of high frequency response equation of radar targets. The method uses the same unvariant character-codes to express the same target of different angles and uses sequential separating of regions of target's reference variables to obtain multiple coding vectors of all regions for every target. The category and pose of target can be determined after a two-staged classification processing such as coding processing of target range profile data and errors correcting processing of coded data. The two-stage classification results are used to target identification as posterior hypothesis to be tested by sufficient convincing and necessary convincing. The character-codes model based pattern recognition method is also adaptive to variation of target angles and controllable in error probability. Time-consuming and complicated iterative computation is not necessary in the train process of pattern recognition.

首先建立了雷达目标的高频频率响应方程，这种方程将目标多散射中心理论与目标局部谐振理论有机地结合起来；进而提出了目标多频响应结构成像方法，这种方法将瑞利区频率响应或谐振区频率响应曲线的不同部位用各种不同的近似方法去逼近，通过特征谱估计方法将目标的局部频响特征与宽带距离响应特征结合起来；然后提出了一种基于姿态角变化区域的序贯划分与多模匹配的特征编码识别方法，这种方法具有能适应目标姿态角的变化以及能控制识别的差错概率α等优点，在目标识别时只需要目标在少数有限个频率激励下的幅频响应数据。

The dynamics equation is established using Lagrange method, and the formula of free frequency is deduced according to modality analysis of general viscous damp. Instantaneous wallops are applied to X, Z dimension respectively, observing the movement of the moving platform, and use ADAMS software to validate the free frequency of the system.

采用Lagrange方程建立了系统动力学方程，根据一般粘性阻尼系统的模态分析法，推导了求解固有振型的公式；分别在X、Z方向上施加一定的瞬时冲击力，观察动平台的运动情况，并采用ADAMS软件验证系统的固有频率。

Two methods are used in this paper to analysis the flight dynamic performance for UAV without empennage by qualitative and quantitative analysis. One is calculating two longitudinal modes by linearizing the basic motion equations. The other is three-dimensional flight simulation research with complete motion equations.

文章主要运用了基本运动方程线化进行基本模态计算分析和建立全量方程进行三维虚拟飞行仿真研究两种方法来定量与定性的分析与评估无尾式无人机的飞行动力学特性。

Based on the compressibility, viscosity resistance and the working house system's deformation etc, flow equations of distribution spool, hydraulic tube and fluid cylinder for 300 MN die forging hydraulic press were established, and dynamics equations of moving beam and upper beam were established based on analysis. The dynamics mechanical-hydraulic coupling model of driving system was established.

考虑流体的可压缩性、粘性阻力及工作框架系统变形等因素，采用解析法建立300 MN模锻水压机动梁驱动系统分配阀口、液压管道、液压缸的流量方程以及动梁和上横梁的动力学方程，得到驱动系统的动态机液耦合模型。

Based on the compressibility, viscosity resistance and the working house system's deformation etc, flow equations of distribution spool, hydraulic tube and fluid cylinder for 300 MN die forging hydraulic press were established, and dynamics equations of moving beam and upper beam were established based on analysis. The dynamics mechanical-hydraulic coupling model of driving system was established.

摘 要：考虑流体的可压缩性、粘性阻力及工作框架系统变形等因素，采用解析法建立300 MN模锻水压机动梁驱动系统分配阀口、液压管道、液压缸的流量方程以及动梁和上横梁的动力学方程，得到驱动系统的动态机液耦合模型。

The eigenvalue equation for the cladding modes of the metal-coated fiber is obtained and the method of solving the complex eigenvalue equation is presented.

分析了金属包层光纤的特点，给出了金属包层光纤包层模的本征方程，并给出了这一复本征方程的求解方法。

He and Nina moved to California and lived at 2005 Ivar Street, Apt.

他和Nina搬到加州，并在2005年伊瓦尔街，公寓生活。

Droperidol （ potently inhibits transfected HERGchannels and this is the probable mechanism for QT prolongation.

氟哌利多有效地抑制了转染的 HERG 钾通道，可能是 QT 间期延长的机制。