搜索结果: 1-15 共查到“知识库 动力系统其他学科”相关记录72条 . 查询时间(3.047 秒)
Polynomial level-set methods for nonlinear dynamical systems analysis
dynamical systems analysis level-set methods
2015/6/19
In this paper, we present a method for computing the domain of attraction for non-linear dynamical systems. We propose a level-set method where sets are represented as sublevel sets of polynomials. Th...
针对某平衡炮武器系统高、低温内弹道性能异常的问题，建立了平衡炮的内弹道方程，并计算了其常、高、低温内弹道性能。通过对内弹道性能计算值与试验结果的对比，找出了造成低温性能异常的原因是发射药片因低温脆性在点火过程产生的严重破碎，高温性能异常的原因是发射药片因高温变软相互黏结导致初始燃面变小。这两种现象及其随机性影响了初速或然误差，尤其是低温下的药片破碎会给发射安全性带来隐患，应更换温度性能较好的发射药...
基于哈密顿动力系统新变分原理的保辛算法之二：算法保辛性质证明
保辛 哈密顿系统 变分原理 作用量
2014/5/16
给出了哈密顿系统的一个新的变分原理,并基于此变分原理,通过选择一个时间步长两端不同广义位移或广义动量为独立变量,给出了四种不同类型的求解哈密顿动力系统的数值方法。本文将分别证明这四类数值方法都是保辛的数值方法。
等熵磁气体动力学方程组的柯西问题
等熵磁气体动力学方程组 柯西问题 古尔沙问题 整体解
2012/11/7
研究等熵磁气体动力学方程组的柯西问题.在初值是连续且分片光滑函数的假设下,首先证明了当初始时刻不出现真空时,解中也不会出现真空.其次,证明了该柯西问题存在唯一的连续且分片光滑的整体解.
Ground state properties in non-relativistic QED
Ground state properties non-relativistic QED
2011/2/21
We discuss recent results concerning the ground state of non-relativistic quantum electrodynamics as a function of a magnetic coupling constant or the fine structure
constant, obtained by the authors...
Let A(t) denote the cluster produced by internal di usion limited aggregation (internal DLA) with t particles in dimension d 3. We show that A(t) is approximately spherical, up to an O(
p log t) er...
The paper is an informal report on joint work with Stefan Haller on Dynamics in relation with Topology and Spectral Geometry. By dynamics one means a smooth vector field on a closed smooth manifold; t...
On Foundations of Newtonian Mechanics
classical mechanics continuum mechanics constitutive equations measures
2011/2/21
Being based on V. Konoplev’s axiomatic approach to continuum mechanics, the paper broadens
its frontiers in order to bring together continuum mechanics with classical mechanics in a new
theory of me...
The existence conditions for periodic motions of the Kowalevski gyrostat in double force field
existence conditions periodic motions Kowalevski gyrostat double force field
2011/3/3
Изучаются особые периодические движения (критические точки ранга 1 интегрально-
го отображения), найденные в работе М.П.Харламова (Механика твердого тела, вып. 37,
2007) в интегрируемой задаче о дви...
A boundary matching micro/macro decomposition for kinetic equations
boundary matching micro/macro decomposition kinetic equations
2011/1/21
We introduce a new micro/macro decomposition of collisional kinetic equations which naturally incorporates the exact space boundary conditions.
Principal dynamical components
Principal component analysis time series empirical orthogonal functions
2011/2/22
A new procedure is proposed for the dimensional reduction of time series. Similarly to principal components, the procedure seeks a low-dimensional manifold that minimizes information loss. Unlike prin...
Regularity "in Large" for the 3D Salmon's Planetary Geostrophic Model of Ocean Dynamics
planetary geostrophic model global regularity ocean dynamics model global circulation
2011/2/28
It is well known, by now, that the three-dimensional non-viscous planetary geostrophic model,
with vertical hydrostatic balance and horizontal Rayleigh friction, coupled to the heat diffusion and tra...
Reynolds number dependence of kinetic helicity decay in linearly forced turbulence
Reynolds number dependence linearly forced turbulence
2010/12/28
The decay of kinetic helicity is studied in numerical models of forced turbulence using either an externally imposed forcing function as an inhomogeneous term in the equations or, lternatively, a term...
Radially symmetric and azimuthally modulated vortex solitons supported by localized gain
Radially symmetric azimuthally modulated vortex solitons localized gain
2010/12/28
We discover that a spatially localized gain supports stable vortex solitons in media with cu-bic nonlinearity and two-photon absorption. The interplay between nonlinear losses and gain in amplifying r...
A note on dynamical systems defining Jacobi's theta-constants
Jacobi’s theta-constants modular forms Poisson structures
2010/12/28
We propose a system of ordinary differential equations which defines Jacobi’s theta-constant series. The relations of this system to the classical Darboux–Halphen equations and equations introduced by...