查询词典 transient current

By using this method, the angular frequency, amplitude, initial phase angle, decay constant of each component in transient voltage and/or current waveforms can be precisely extracted. Also, all other kinds of transient procedure can be analyzed by this method. Thirdly, a new definition of generalized instantaneous reactive power and generalized instantaneous reactive current in dq0 coordinates under any nonsinusoidal and unbalanced three-phase circuit is proposed for the first time. The detection and compensation method for different instantaneous reactive currents are also concerned.

本文首先提出了用于快速高精度频谱分析的一种改进快速傅立叶变换方法，该法具有速度快、精度高、抗混迭、不受采样定理约束、可以分析出谐次大于N／2的频谱系数等特点，可方便地应用于电力系统谐波分析及其它各类频谱分析；然后提出了基于非线性最小二乘优化法的电力系统暂态波形分析方法，可准确求出电力系统暂态电压、电流波形中各个分量的角频率、幅值、初相角及衰减常数，并可广泛应用于各类暂态过程波形分析。

In this part, the characteristics of transient responses of flexible rotor systems with arbitrarily distributed mass on isotropic or anisotropic supports passing through several critical speeds seguencially are examined. Here, the current knowledge of rotor dynamics on the eigenproblem of damped free whirling vibration, the generaliged damped mode theary, the transient forced vibration and so on combined with KBM asymptotic method in the nonlinear vibration theory is employed and extended.

作者综合运用并引伸推广转子动力学关于阻尼自由回旋振动的特征问题、广义阻尼模态理论、瞬态强廹振动等現代理论和方法，结合非线性振动理论中的KBM渐近法，提出自己独創見解和覌点，成功地建立起正回旋和逆回旋两种情况下转子通过临界点的瞬态振动一阶微分方程组，可以在临界点的邻域内从事方程的数值积分计算。

A new method of obtaining secondary electron yield and secondary Cs〓 ionization probability by detecting target current and primary ion current under Cs〓 bombardment is put forward The dependence of Cs〓 ionization probability on primary ion energy, primary beam current and substrate compositions, as well as the dependence of secondary ion intensity on erosion time during transient period has been studied The mechanisms of secondary ion emission are explained

二、提出了通过测量靶流和一次束流求取Cs〓轰击下二次电子产额和二次Cs〓离化率的方法，实验研究了一次离子能量、束流强度及不同基体对二次Cs〓离化率的影响和瞬态过程中二次离子强度的变化规律，并对发射机理做了解释。

Boundary polynomial point interpolation mesh-free method and boundary radial point interpolation mesh-free method were presented, based on polynomial basis and radial basis respectively for transient eddy current analysis, and their interpolation shape functions satisfy the Kronecker delta function and the essential boundary conditions can be directly imposed on the boundary nodes. An example on analyzing transient eddy current of a square metal column was set to prove the validity of the proposed methods, and a comparison on accuracy between BPPIM and BRPIM was analyzed as well.

运用多项式点插值法和径向基点插值法构造形函数，推导了适合于工程电磁场瞬态涡流问题的多项式基点插值边界无单元方法和径向基点播值边界无单元方法，这两种方法的空间插值形函数满足Kronecker delta条件，从而强加边界条件可以直接施加在边界点上，以金属长方柱的瞬态涡流分析作为数值算例，证实了两种方法的正确性和有效性，并对两种基类的点插值法进行了精度分析和比较。

Through the analysis, the paper reaches the following basic conclusions: The quantity of Chaoyang district"s transient population will increase continuously, residential period will prolong gradually and renting house will still be the major residential way of transient population; transient population play a positive role in the district"s socioeconomic development, but on the other side they make city infrastructures more difficult to bear the existent heavy burden, difficulty in city management is increased; transient labor force mainly undertake the supplementary role of the district labor force, but along with the open of the labor force market step by step and the further improving of the quality of transient labor force, the competition between transient labor force and local labor force tends to be intense; the current management policy of transient population in Beijing exists some problems, which stresses management and makes light of service, stresses duties and makes light of rights and interests, stresses planning and makes light of market, stresses outside and makes light of inside, but the policy is tending to the developing direction that is helpful for transient population to flow.

文章通过分析得出以下基本结论：朝阳区外来人口的数量还会继续增长，居住时间逐渐延长，租住房屋仍然是外来人口最主要的居住方式；外来人口在为本区社会经济发展起到积极作用的同时，也使城市基础设施不堪重负，城市管理难度加大；外来劳动力主要承担着本区劳动力的补充角色，但随着劳动力市场的逐步开放和外来人口素质的进一步提高，外来劳动力与本地劳动力的竞争趋于激烈；北京市现行的外来人口管理政策存在着重管理而轻服务、重义务而轻权益、重计划而轻市场、重外部而轻内部的问题，但正趋于有利于外来人口流动的方向发展。

Establish the steady-state and transient model using the three hydrodynamics equations (Continuity equation, Momentum equation and Energy equation). By comparing different state equation, it selects the BWRS state equation which is considered the most accurate state equation in current natural gas measurement. It calculates compression factor, density and other Thermal parameters based on BWRS state equation. In Numerical solution of the steady-state and transient model, compression factor, friction coefficient and all the other Thermal parameters are recalculated in each small time step to reduce the numerical calculation error.

在稳态模型的建立上，利用流体力学三大方程(连续性方程、运动方程和能量方程)，通过比较不同的状态方程选用了目前被认为最精确的用于天然气计量的BWRS状态方程，并以此方程为基础进行压缩因子、密度等热物性参数的计算；在稳态模型的求解上，选用容易计算，精度较高的标准型龙格—库塔(Runge-Kutta)法进行数值求解，并且在迭代过程的每一小步都重新计算燃气的压缩因子，摩阻系数等所有的计算参数，以减少数值计算的误差。

A prediction model has been proposed to deal with threshold voltage shift as a function of 1MeV neutron flux and gate oxide thickness, and to deal with room-temperature annealing of threshold voltage shift induced-by 〓Coγ as a function of electric field and gate oxide thickness. The commonness and individuality of MOS device degradation between hot-carrier effect and ionizing radiation were investigated. The dependence of substrate current, gate current and threshold voltage shift due to hot-carrier on gate oxide thickness were simulated with MEDICI-2D simulator. The photocurrents of PN junction and bipolar transistor were studied. Their transient responses on varied bias voltages, pulse durations and absorbed doses were simulated. The influences of NPN base width on base and collector photocurrents were investigated. We also studied 1MeV neutron displacement damage in PN junction, and calculated reverse current leakage under the neutron flux of 2. 67×10〓 per square centimeter. 3 The study of nondestructive screening method for MOS radiation tolerance A theoretical and experimental study of nondestructive screening methods for radiation tolerance of nMOS and pMOS were firstly fulfilled. We determined the informative parameters pertinent to the method and proposed how to deal with experimental data and verify obtained results statistically, as well as make the required steps for nondestructive screening. Based on the experimental data of 180 samples of discrete pMOS devices, the relation between sample quantity and correlation coefficient, screening equation, and other significant results were obtained from the threshold voltage shifts of pre-and post-irradiation samples.

二、分立器件电离和位移辐射损伤响应研究在国内首次开展了电离辐射引起的氧化层阈值电压漂移和退火理论研究，编程计算了1MeV中子引起的MOS器件阈值电压漂移与中子通量及栅氧厚度的关系，计算了〓Coγ光子引起的阈值电压漂移及退火的时效曲线与纵向电场和栅氧厚度的关系等，对评估MOS型集成电路电离损伤和加固方法研究，以及论文中开展的MOSFETs无损筛选方法研究奠定了基础；分析了MOS器件热载流子损伤效应与辐射电离损伤效应之间的异同性，利用二维模拟软件MEDICI-2D模拟了衬底电流和栅电流，在不同栅氧厚度下随栅压的变化曲线，计算了热载流子效应造成的阈值电压漂移，研究结果对当前存在的以热载流子效应研究取代电离辐射损伤实验研究的设想，具有重要的参考价值；开展了PN结和双极晶体管电离光电流研究，计算了不同偏压、不同辐射脉宽和不同吸收剂量下PN结光电流的瞬时响应，计算了不同辐射脉宽下NPN晶体管基极电流和收集极电流的瞬时响应，以及基区宽度对NPN晶体管光电流的影响，研究结果对双极器件抗电离辐射损伤响应及加固方法研究具有重要意义；在国内首次开展了器件位移损伤的理论研究，分析了辐射产生的缺陷对电性能的影响，计算了注量为2.67×10〓cm〓的1MeV中子产生的缺陷对PN结反向电流的影响。

So, When the power system is in transient, the sliding mode control rule is chose directly to make transient component decrease quickly, and when the power system is in stability, the direct current control method based on voltage space vector method is imported to make the error current reduce to zero by inches and avoid surge.

为此，当系统处于暂态时，论文直接选择滑模控制率使暂态分量迅速减小，当系统处于稳态时，引入基于电压空间矢量的直接电流控制方法，使误差电流趋于0缓慢变化，在有效补偿系统无功的同时，提高了系统的动态特性，并大大降低了系统振荡的可能性。

The measuring systems are successfully used in the electromagnetic pulse measurement generated by impulse voltage discharge and switch operation in 500kV substations. Full waveforms of transient electric field, transient magnetic field, transient voltage of high frequency relay channels and low voltage alternative current power during switch operation period have been obtained, and the fast transient pulses in high frequency relay channels and AC power have been caught.

将该套测量系统成功地应用于500kV变电站开关操作产生的电磁脉冲的研究中，得到了开关刀闸操作时暂态电场、磁场、高频通道、交流电压等的完整波形，发现低压交直流电源系统和高频保护通道中存在非常严重的脉冲群干扰，初步解释了变电站二次电源模块经常损坏和高频保护经常误动的原因，提出了加强保护和研究的建议，进一步验证了测量系统的先进性。

In this paper, using transient energy function as the assessment of system stability and applying the derivative of TEF to determine the control strategy of Fault Current Limiter with controllable series compensation in transient stability process, the transient stability characteristics can be effectively improved and subsequent oscillation can be quickly damped.

1引言具有可控串联补偿功能的故障限流器(FCL with controlled series compensation)作为灵活交流输电的主要装置之一，装设在并行线路具有许多优点。如图1所示，正常工作时，它能连续、快速、大范围地调节线路阻抗，从而灵活调节线路电流、增强系统阻尼、改善系统动态性能、抑制次同步振荡。

I am sure after a few weeks of adaptation and familiarization I will have no difficulty in functioning on a daily basis in an English speaking society or in participating fully in graduate studies.

在大学的三年的学习生活不仅给予我自身的充实，更重要的是磨练和培养了我较强的自觉能力和严谨，踏实的作风以及不怕困难的精神，对未来充满了信心！

As the first volcanoes erupted, one of the gases that bellowed out was steam.

在第一批火山喷发时，喷出的气体之一就是水蒸汽。