查询词典 instabilities

The quasi-perpendicular collisionless shock consists of foot, ramp and a series of overshoots and undershoots, after travelling back upstream for a short distance, the reflected protons gyrate back into the downstream where an temperature anisotropy is formed due to an anisotropy of velocity distribution, then excite Alfvén ion cyclotron waves and mirror waves that dissipate the kinetic energy into heat; At quasi-parallel collisionless shocks, the reflected protons can travel far upstream, and lead to the generation of ion beam instabilities which excite large-amplitude right-hand polarized ultralow-frequency resonant waves whose frequencies are are about〓 These waves are convected back downstream by solar wind and gradually merge to form the downstream state, in the meantime new waves are generated continuously in the upstream, this process where ULF waves are generated and merge into downstream state is cyclical.

准垂直无碰撞激波系由根部、斜坡区以及一系列的低冲和过插组成，被激波反射的质子向激波上游运动很短的距离就在回旋作用下再次向下游运动，和激波发生相互作用以后进入激波的下游，在激波的下游引起质子速度分布的各向异性，进而引起激波下游温度的各向异性，激发起Alfvén离子回旋波和镜波，将激波上游的动能耗散成激波下游的热能；在准平行无碰撞激波(θ〓＝10°)情况下，这部分质子能向激波上游运动很大一段距离，并在激波的上游激发起束流不稳定性，引起大振幅的低频波动。

A new model is presented for the physically-consistent description of plastic instabilities referred to PLC effect. The model takes account of two competing processes during the DSA on micro-scale: the additional pinning of diffusing solute atom on mobile dislocations and the unpinning of the mobile dislocation with the aid of thermal activation.

建立了一个基于动态应变时效过程中热激活机制和二阶应变梯度空间耦合方式的宏观唯象模型，该模型刻画了材料内部在微细观尺度上彼此协同和相互竞争的两个过程：溶质原子对可动位错的时效钉扎和可动位错在热激活辅助下的挣脱。

ABSTRACT The RF problems and beam instabilities driven by higher order modes of RF cavity of Hefei Light Source were studied in this thesis.

本论文描述合肥同步辐射储存环的束流负载效应及由高频腔的高次模引发的多束团不稳定问题。

They experimented with the effects of "artificially induced ionospheric depletions on very low frequency wave lengths, on equatorial plasma instabilities, and on low frequency radio astronomical observations over Roberval, Quebec, Kwajelein, in the Marshall Islands and Hobart, Tasmania" Advanced Space Research, Vo1.8, No.

他们实验&在近赤道离子不稳定区域以甚低频波长人工诱导电离层损耗，或者对魁北克罗伯威尔、马绍尔群岛桂哲林和塔斯马尼亚州霍巴特的低频无线电天文观测&（《高级太空研究》，卷1.8，1号，1988）。

The ballast employs universal techniques suitable for operating HID lamps of different types, wattages and manufacturers despite the occurrence of acoustic resonance/arc instabilities among these lamps over a fairly broad frequency range.

镇流器在较宽的频率范围上采用适于操纵不同类型、瓦特数和制造商的HID灯的通用技术，尽管这些灯中产生了音频共振／弧光不稳。

Evidence suggests that 1 under more stable stratification, the basic flow, if moving faster at low and high levels (particularly in the presence of jets there), allows a resulting meso-β unsteady wave to propagate eastward with respect to basic flow and even at greater velocity compared with it; 2 vertical windspeed shear of basic flow causes instabilities of the TWT perturbation; 3 considering the second derivative of basic-flow wind with respect to z (denoted by zz≠ 0 which is simply given as β* hereafter) the expression for the phase velocity of vortex Rossby wave is obtained, which is unidirectional in propagation with respect to basic flow; 4 VRoW has its physical origin from β*, i.e., from z-varying heterogeneities of y-direction averaged vorticity of the basic flow field; 5 VRoW phase velocity is associated with zonal wave number k, its energy is dispersive and the group velocity exists in the x direction; 6 when windspeed meets the condition of β*, TWT disturbance instability may be that of mixed VRoW and gravity wave; 7 if basic flow is subject to linear shear but does not meet the condition of β*, the TWT instability is that of inertia-gravity wave.

在大气层结比较稳定的情况下，如果基本气流在低层和高层较大(有可能存在低空急流和高空急流)，此时产生的β中尺度不稳定扰动相对于基流向东传播，甚至于快速向东传播。基本气流在垂直方向上的风速切变对于中尺度横波型的扰动起着不稳定的作用。如果考虑基流的二次切变，可以得到涡旋Rossby波的相速度表达式，涡旋Rossby波相对于基本气流是单向传播的。涡旋Rossby波产生的物理根源是基本流场的风速二次切变，亦即基本流场y方向的平均涡度在空间z方向上的不均匀所致。涡旋Rossby波的相速度与纬向波数也有关，它的能量是频散的，其在纬向x方向也存在群速度。在基本流场的风速存在二次切变时，横波型不稳定可能是混合的涡旋Rossby重力波的不稳定；而在基本流场的风速仅仅存在线性切变，不存在二次切变时，横波型扰动的不稳定则是重力惯性波的不稳定。

The thesis mainly studies the potential well effect on the bunch longitudinal distribution, on the basis of correlated wake field, coupling impedance and various instabilities. Then the inductance and resistance parts of coupling impedance of the KEK-ATF damping ring are obtained from the analyses of the measured bunch longitudinal distribution.

本论文在充分阐述与束流集体效应相关的尾场、耦合阻抗和各种不稳定性的基础上，着重研究了势阱效应对束团纵向分布的影响，并由实测的KEK-ATF阻尼环的束团纵向分布得到了其耦合阻抗的电感和电阻部分。

Furthermore all possibilities of local plastic deformations and instabilities have to be covered by such an analytical model.

而且，在分析模型中还需要考虑所有的局部塑性变形和不稳定性。

Are given out, and then a survey and review of the literature up to 1980 is given of the linear theory of the ideal and resistive hydromagnetic instability of tokamak. Some important characteristics of MHD instabilities are discussed in more details. Since sawtooth oscillation is discovered in ST tokamak, many theory models are proposed to explain the disruptive part of sawtooth, however, there is no satisfactory theory of the internal disruption.

本论文对锯齿振荡和L-H转换作了研究，主要开展的工作如下：在论文的开始部分，给出了基本的MHD方程，对至1980年文献水平的托卡马克中理想和电阻性情况下的磁流体不稳定性的线性理论作了简要回顾，讨论了某些重要的不稳定性特征。

But also in terms of some of the instabilities in the financial system.

还在我们金融系统中的某些不稳定性方面。

The absorption and distribution of chromium were studied in ryeusing nutrient culture technique and pot experiment.

采用不同浓度K2CrO4(0，0.4，0.8和1.2 mmol/L)的Hoagland营养液处理黑麦幼苗，测定铬在黑麦体内的亚细胞分布、铬化学形态及不同部位的积累。

By analyzing theory foundation of mathematical morphology in the digital image processing, researching morphology arithmetic of the binary Image, discussing two basic forms for the least structure element: dilation and erosion.

通过分析数学形态学在图像中的理论基础，研究二值图像的形态分析算法，探讨最小结构元素的两种基本形态：膨胀和腐蚀；分析了数学形态学复杂算法的基本原理，把数学形态学的部分并行处理理念引入到家实际应用中。