Hamilton's equations of motion for non-conservative systems     

Frank Thomas Tveter 《Celestial Mechanics and Dynamical Astronomy》1994,60(4):409-419

This paper deals with the Hamilton equations of motion and non conservative forces. The paper will show how the Hamilton formalism may be expanded so that the auxiliary equations for any problem may be found in any set of canonical variables, regardless of the nature of the forces involved. Although the expansion does not bring us closer to an analytical solution of the problem, it's simplicity makes it worth noticing.The starting point is a conservative system (for instance a satellite orbiting an oblate planet) with a known Hamiltonian (K) and canonical variables {Q, P}. This system is placed under influence of a non-conservative force (for instance drag-force). The idea is then to use, as far as possible, the same definitions used in the conservative problem, in the process of finding the auxiliary equations for the perturbed system.  相似文献   

关于正确建立渗流数学模型的若干问题     

郭东屏 《地球科学与环境学报》1988,(4)

在某些文献中,有原则性问题的渗流数学模型不乏其见。本文什对问题发生的原因,论述了关于正确建立渗流数学模型的若干要点,给出了体现要点的若干实例分析。  相似文献   

Figures of equilibrium in close binary systems     

J. A. López Ortí  A. López García  R. López Machí 《Celestial Mechanics and Dynamical Astronomy》1992,53(4):311-322

The equilibrium configurations of close binary systems are analyzed. The autogravitational, centrifugal and tidal potentials are expanded in Clairaut's coordinates. From the set of the total potential angular terms an integral equations system is derived. The reduction of them to ordinary differential equations and the determination of the boundary conditions allow a formulation of the problem in terms of a single variable.  相似文献   

Wavelet analysis and applications to some dynamical systems     

Ph. Bendjoya  E. Slezak 《Celestial Mechanics and Dynamical Astronomy》1993,56(1-2):231-262

For about five years the wavelet transform technique has given interesting results in a great number of different fields such as mathematics, quantum mechanics, signal analysis and image processing, cluster analysis... The wavelet transform appears as a new time-frequency method which is particularly well-suited to detect and to localize discontinuities and scaling behaviours in signals. The main properties of the wavelet transform and its improvements over classical analyzing methods are summarized. Some results among the first applications to the dynamical systems are presented: solution of partial differential equations, fractal and turbulence characterization, and asteroid family determination from cluster analysis.  相似文献   

Explicit solutions of the three-dimensional inverse problem of dynamics,using the frenet reference frame     

François Puel 《Celestial Mechanics and Dynamical Astronomy》1992,53(3):207-218

Given a two-parameter of three-dimensional orbits, we construct the unit tangent vector, the normal and the binormal which define the Frenet reference frame. In this frame, by writing that the force is conservative, we explicitly obtain the potential as a function of the energy along the trajectories and of its derivatives.Observatoire de Besançon  相似文献   

Correlation of Unconfined Compressive Strength with Young’s Modulus and Poisson’s Ratio in Gypsum from Sivas (Turkey)     

A. T. Arslan  M. Y. Koca  T. Aydogmus  H. Klapperich  H. R. Yılmaz 《Rock Mechanics and Rock Engineering》2008,41(6):941-950

  相似文献   

随机镇定与反镇定概述     

黄礼荣  邓飞其  宋明辉 《南京气象学院学报》2017,9(3):262-273

本文概述了随机镇定与反镇定理论的研究现状.主要回顾了一个微分方程的随机镇定与反镇定普遍理论及其发展,并围绕该理论的应用和扩展从四个方面阐述连续时间系统噪声镇定理论的当前发展概况.此外,本文还概述了离散时间系统随机镇定方面的最新进展.  相似文献   

中立型随机发展系统的适定性     

徐道义 《南京气象学院学报》2017,9(4):400-405

针对中立型随机发展系统的温和解与轨道温和解,给出了其存在唯一性与渐近估计的充分条件,推广了经典的Pazy定理与一些近期文献的主要工作.  相似文献   

关于孔隙—裂隙流的定性研究     

梅茗 《华东地质学院学报》1992,15(1):95-100

  相似文献   

MODELING SEDIMENT PROCESSES ON SMALL WATERSHEDS:A CONCEPTUAL FRAMEWORK Ⅰ. BROAD SHALLOW FLOW PROCESSE     

Vicente L. LOPES Assistant Professor  School of Renewable Natural Resources  The University of Arizona  Tucson  Arizona  Peter F. FFOLLIOTT Professor  School of Renewable Natural Resources  The University of Arizona 《国际泥沙研究》1992,(3)

A conceptual modeling framework for developing process-based mathematical models of sediment generation, transport, and deposition on broad shallow flow areas is presented. The governing equations relevant to process-based modeling of broad shallow flow sediment processes on small watersheds are presented and the effects of space and time averaging on the predictive equations are described. Starting from the most general one-dimensional, unsteady model of sediment processes, simpler model structures are obtained and the successive simplifications made on the governing equations in order to obtain simpler and less detailed formulations are described. Specific model formulations are given for illustrative purposes and applications of these models to erosion and sediment yield prediction from broad shallow flow areas are shown using sediment data from rainfall simulator plots. In spite of some progress made in the development of process-based erosion and sediment yield models from broad shallow flow areas, further developmental modeling efforts must be based on a clear separation between hydrologic and hydraulic processes, and the soil properties which are significant for each.  相似文献