查询词典 constants

Free Radical ion; Hyperfine coupling constants; Density Functional Theory

自由基离子；超精细偶合常数；密度泛函理论

The physics constants of the impurity was determined as well.

对两种方法的线性和范围、精密度、准确

In the relativistic σ-ω model, the influence of the parameters in self-interaction of σ meson to the equation of state of normal nuclear matter, especially, to incompressibility, effective mass, and coupling constants, is studied in detail. We find that these parameters have an intense relationship to the property of nuclear matter.

在相对论σ-ω模型里，详细讨论了σ介子的自相互作用参数对正常核物质物态方程的影响，特别是对核物质的不可压缩系数、有效质量，以及σ介子与核子、ω介子与核子之间的耦合常数的影响，发现这些参数与核物质的性质之间有紧密的联系。

ABSTRACT Aiming at problems of trans-vector controller in a vehicle-carried induction motor such as variable rotor and stator resistance following motor temperature, and their inductance varying with flux saturation degrees. Firstly, CSI and VSI are introduced, for CSI, it can hold the advantages both FOC and DTC using stator flux directional, PI parameter and simulation are also introduced. Secondly, equations of IM in the synchronous rotary frame and its static counterpart, as figuring in the saturation condition of magnetic field, are dealt in this paper and the simulation results are presented. Thereafter, the parameter designing of PI trans-vector controller is processed, which features the non-linear model. In practical realization, as neglecting the dynamical change of motor inductance, this paper employs online modification of inductance parameters, according to the flux saturation, then transforms the non-linear equations into linear ones, and so compacts the structure of controller. Thirdly, in view of the maximum torque output is extraordinary requisite when Electrical Vehicle start up, accelerate, and overtake, this paper issues the maximum torque when both inverter and battery capacity is corporeally definite. Fourthly, on-line differentiating and analyzing both rotor's time constants and its flux by using the expanding order reduction and discrete Kalman filter equation are fathomed, in order to realize high-performance trans-vector algorithm, and also the simulation results are presented. Fifthly, the close-loop regenerative brake system, when the EV's torque is set constant, is deduced; at the same time, unification of electric drive model and brake model is executed. Combined with maximum charge current demands, the mathematical model for online yielding torque as a demand.

本论文针对车载异步电机在矢量控制器所遇到的问题：定转子电阻随温度变化及随电机饱和程度变化的转子电感及定子电感而影响电机调速性能提出一套完整的解决方案：分析了电流型逆变器和电压型逆变器在实现矢量控制时控制器参数的计算，分析出对于电流型逆变器在采用定子磁场定向时，其性能同时具有矢量控制和直接转矩控制两者的优势，并对电压型逆变器在转子磁场定向下的模型进行了仿真研究；建立异步电机非线性模型，推导出考虑磁饱和时异步电机在同步旋转坐标系及静止坐标系下的方程，并做出了仿真结果，建立异步电机在非线性模型下的矢量控制调节器的PI参数设计，在实际应用中，若忽略电机电感的动态变化，可以根据当前的磁路饱和状态而在线修正电感参数，从而将非线性方程线性化，降低控制器的复杂度；考虑到电动汽车在起动和加速超车时需要电机有最大转矩输出，本文讨论在逆变器容量一定和电池供电能力有限的情况下电机最大转矩输出问题；推导了异步电机扩展降阶、离散卡尔曼滤波方程在线辨识转子时间常数和转子磁通，用于实现高性能的矢量控制算法，并给出了仿真结果；推导出了电动汽车恒转矩给定的闭环回馈制动系统，实现了电动控制模型和制动模型的统一，而且结合铅酸电池最大充电电流的要求，为制动转矩在线给定建立了数学模型；设计了基于双DSP系统的高性能矢量控制器软硬件框图，并以大量实验数据说明矢量控制在电动汽车应用的实际应用状况。

At the same time, the values range of two kinds of nonsquare constants and their values in real inner product space are given .

同时给出了两种点态非方常数的取值范围，和实内积空间中两种点态非方常数的值。

In this paper we apply a method based on a special integral inequality, to show that the solution of a damped coupled system decays exponentially, and to obtain precise resalt of the constants in the estimates.

应用一个新的积分不等式，得到了具阻尼的非线性耦合方程组的衰减估计，以及精确的估计常数。

Phonon spectrum throughout the Brillouin zone and the interatomic force constants are obtained using the density-functional perturbation theory by the linear response method.

在密度泛函微扰理论的框架下采用线性响应的方法得到了整个声子谱，并分析了原子间力常数。

If only the interatomic force are considered, atomic stress amounts to the potential density in the resultant force field generated by the neighboring atoms, and atomic elastic constants equals to the potential density increment in the same resultant force field.

如果只考虑原子间作用力的影响，原子应力等于该原子在周围邻域原子合成张量力场中的势能密度，原子弹性常数等于发生单位应变时原子在邻域原子合成力场中势能密度的增量。

The internuclear distances and force constants of the elementary molecules as well as of the nitrides and halides, exhibit a similar behavior

单质分子和氮化物与卤化物，其核间距与力常数都表现有相似的行为。

These comparison show that all calculation results, such as dissociation energy, equilibrium internuclear distance and rotation-vibration constants, are better agreement with experimental results than other theoretical ones.

结果表明，无论是离解能、平衡核间距还是分子的振转常数，利用九参数Murrell-Sorbie势能函数得到的结果与实验结果相比较，都明显好于其他理论结果。

A historical region of southwest France between the Pyrenees and the Garonne River. The duchy of Aquitaine was joined with France after the marriage of Eleanor of Aquitaine to King Louis VII in1137, but its possession was disputed after her subsequent marriage to Henry II of England.

阿基坦法国西南部一个历史地区，位于比利牛斯山和加隆河之间，在1137年阿基坦的埃莉诺与国王路易斯七世结婚之后阿基坦公国加入法国，但当她再嫁英国亨利二世后，其归属权便受到争议

There are moments when I look at the smiling , happy faces of my expectant staff and wonder how they will cope when confronted by an outraged housemaster along with an unrepentant and recalcitrant bleached blond teenager in 18 years ' time .

有时候，我看着那些满怀期待的员工微笑，幸福的脸，想着当他们遇到一位愤怒的宿舍管理员和一位不知悔改，叛逆，而且将头发染成白色的18岁少年时，他们会如何处理。