查询词典 quasi-periodic

We investigate mainly solving the hyperbolic and parabolic equations by using the MQ quasi-interpolation. The underlying idea of our means is that: employing the derivative of the MQ quasi-interpolation to approximate the spatial derivative of the PDE, while the approach of the temporal derivative of the PDE is used a finite difference.

我们主要就MQ拟插值在双曲型方程和抛物型方程中的应用进行了研究，其基本思路是：利用MQ拟插值的导数逼近微分方程的空间导数，而微分方程的时间导数则采用有限差分逼近。

Weak quasi-bialgebra (quasi-Ilopf algebra) is an associative algebra with unit 1 a non-unital algebra map i.

弱拟双代数是一个具有单位1的结合代数，具有余乘法与余单位。

Firstly, on the base of the strictly monotone map, we provide the definition of strictly invariant quasi-monotone map, it is the extent of the strictly monotone mapping, at the same time, it is the especial case of the invariant quasi-monotone map, too. It is supported by some examples.

在理论部分做了三方面的工作：首先，在严格拟单调映射的基础上，提出了严格不变拟单调映射，它是严格拟单调映射的推广，同时也是不变拟单调映射的特殊情况，举例加以说明。

It enlarges the range of quasi-linear Born approximation, and makes the prestack depth migration method based on quasi-linear Born approximation to be able to adapt strong lateral velocity variation.

在散射波场计算中，使用了一个更稳定的散射波场计算公式，扩大了拟线性Born近似的应用范围，使基于拟线性Born近似的叠前深度偏移方法能够适应更强的横向速度变化。

Properties of efficient portfolios and the efficient frontier to the model are systematically analyzed. Our main results concerning the properties are: every efficient portfolio can be solved by minimizing portfolio risk under a given level of portfolio return or by maximizing portfolio return under a given level of portfolio risk; on the efficient frontier, the risk is a convex and strictly increasing function of the return and the return is a concave and strictly increasing function of the risk; the utility function on the efficient frontier can be expressed as a quasi-concave function of the risk or the return if the investor's utility function is quasi-concave.

从理论上系统地对该模型下的有效投资组合和有效前沿的性质进行了分析，结果表明：每一个有效投资组合可通过在给定期望收益水平的条件下最小化投资组合风险来获得，或者在给定风险水平的条件下最大化期望投资组合收益来获得；在有效前沿上，风险是收益的严格单调递增凸函数，收益是风险的严格单调递增凹函数；当投资者的效用函数是拟凹函数时，则有效前沿上的效用可表达成风险或收益的拟凹函数。

According to the variations in friction coefficient, wear rate, temperature of tribo-pair and tribo-surface micro hardness with time, the tribological process lubricated by oil containing Mg_6Si_4O_(10)_8 shows quasi-periodicity with characteristic of damped oscillation, and quasi-period is 200 h; micro-hardness of the worn surface is one time higher than that of 45~# steel substrate.

在实验室条件下，验证了主要组分为Mg6Si4O108的金属磨损自修复剂在45#钢摩擦副表面形成修复保护层的能力，得到了厚3～6 μm的反应层；采用Falex型摩擦磨损试验机进行了长达400 h的摩擦磨损试验，研究了在Mg6Si4O108润滑下45#钢摩擦副的摩擦磨损性能、摩擦副摩擦表面显微硬度和温度随时间变化的情况。

We present the fundamental theories of Noether symmetries and conserved quantities of mechanco-electrical dynamical systems, including variation principle of the system, Noether symmetry transformation, Noether quasi-symmetry transformation, generalized Noether quasi-symmetry transformation, Killing equations, Noether theorem, the form of conserved quantity. And then the basic theory of Lie symmetry is advanced, including the determining equation, structure equation and the form of conserved quantity.

给出机电动力系统的Noether对称性和守恒量基本理论，包括系统的变分原理、Noether对称性变换、Noether准对称性变换、广义Noether准对称性变换、Killing方程、Noether定理和守恒量的形式；给出机电动力系统Lie对称性的基本理论，包括确定方程、结构方程以及守恒量的形式。

This paper describes the components and structure of advanced signaling system: Automatic Train Control system, analyzes the function and classification of its three subsystems: ATS, ATP and ATO, with emphasis on currently widely adopted ATC system-Quasi-Moving-Block signaling system, which works on coded digit track circuit, and discusses the operating principles of coded digit track circuit and the features of train control of Quasi-Moving-Block signaling system.

本文详细讨论了应用于城市轨道交通的先进的信号系统——列车运行自动控制系统的组成和结构，对其三个子系统：列车自动监控系统ATS、列车自动保护系统ATP、列车自动运行系统ATO的功能和分类进行了详细分析和比较。

From the opposite direction of the parameter variation, the chaotic quasi-attractor suddenly changes to a chaotic quasi-transience due to the sudden appearance of a stable elliptic island chain as the leaking hole inside it. This resembles the conventional crises.

从相反的参数变化方向看，混沌类吸引子在此参数临界值由于它内部突然出现一个稳定的椭圆岛链作为逃逸孔洞而突然转变为混沌类瞬态，这类似于传统的激变行为。

Based on results ofexperiment, it proposes the hypothesis of quasi-crystal disassociation and recrystallization in the quasi-crystal p...

解释了碱处理去原纤化及乙烯基单体接枝防原纤化的原因。

Neither the killing of Mr Zarqawi nor any breakthrough on the political front will stop the insurgency and the fratricidal murders in their tracks.

在对危险的南部地区访问时，他斥责什叶派民兵领导人对中央集权的挑衅行为。

In fact,I've got him on the satellite mobile right now.

实际上 我们已接通卫星可视电话了