NUCLEAR COLLISIONS MODELS WITH BOLTZMANN OPERATORS

2000 ◽  
Vol 10 (04) ◽  
pp. 479-505 ◽  
Author(s):  
S. DELLACHERIE ◽  
R. SENTIS
Keyword(s):  
Numerical Methods ◽  
Asymptotic Analysis ◽  
Numerical Results ◽  
Nuclear Collisions

We describe a model related to nuclear collisions using Boltzmann operators. An asymptotic analysis is performed concerning the gain operator for the outgoing particles. Some numerical methods related to this model are also described and numerical results are given.

scholarly journals Numerical methods for solving the multi-term time-fractional wave-diffusion equation

2013 ◽  
Vol 16 (1) ◽  
Author(s):  
Fawang Liu ◽  
Mark Meerschaert ◽  
Robert McGough ◽  
Pinghui Zhuang ◽  
Qingxia Liu
Keyword(s):  
Numerical Methods ◽  
Theoretical Analysis ◽  
Diffusion Equation ◽  
Fractional Derivatives ◽  
Fractional Laplacian ◽  
Numerical Results ◽  
Diffusion Equations ◽  
Time Space ◽  
Methods And Techniques ◽  
Wave Diffusion

AbstractIn this paper, the multi-term time-fractional wave-diffusion equations are considered. The multi-term time fractional derivatives are defined in the Caputo sense, whose orders belong to the intervals [0,1], [1,2), [0,2), [0,3), [2,3) and [2,4), respectively. Some computationally effective numerical methods are proposed for simulating the multi-term time-fractional wave-diffusion equations. The numerical results demonstrate the effectiveness of theoretical analysis. These methods and techniques can also be extended to other kinds of the multi-term fractional time-space models with fractional Laplacian.

Observations Regarding Numerical Results Obtained by the Floquet-Method

2013 ◽  
Author(s):  
Till J. Kniffka ◽  
Horst Ecker
Keyword(s):  
Numerical Methods ◽  
Monodromy Matrix ◽  
Mathieu Equation ◽  
Numerical Results ◽  
The Other ◽  
Benchmark Problem ◽  
Stability Studies ◽  
Floquet Method ◽  
System Equations ◽  
Time Periodic

Stability studies of parametrically excited systems are frequently carried out by numerical methods. Especially for LTP-systems, several such methods are known and in practical use. This study investigates and compares two methods that are both based on Floquet’s theorem. As an introductary benchmark problem a 1-dof system is employed, which is basically a mechanical representation of the damped Mathieu-equation. The second problem to be studied in this contribution is a time-periodic 2-dof vibrational system. The system equations are transformed into a modal representation to facilitate the application and interpretation of the results obtained by different methods. Both numerical methods are similar in the sense that a monodromy matrix for the LTP-system is calculated numerically. However, one method uses the period of the parametric excitation as the interval for establishing that matrix. The other method is based on the period of the solution, which is not known exactly. Numerical results are computed by both methods and compared in order to work out how they can be applied efficiently.

scholarly journals A PRACTICAL PERFORMANCE INDEX FOR COMPARING OF OPTIMIZATION SOFTWARE

2014 ◽  
pp. 7-12
Author(s):  
Andrea Attanasio ◽  
Patrizia Beraldi ◽  
Francesca Guerriero
Keyword(s):  
Numerical Methods ◽  
Performance Index ◽  
Relative Efficiency ◽  
Numerical Results ◽  
Optimization Software ◽  
Practical Performance

In this paper we propose a new practical performance index for ranking of numerical methods. This index may be very helpful especially when several methods are tested on a large number of instances, since it provides a concise and precise idea of the relative efficiency of a method with the respect to the others. In order to evaluate the efficiency of the proposed rule, we have applied it to the numerical results presented on previously published papers.

scholarly journals Solving Dual Fuzzy Nonlinear Equations via Shamanskii Method

2018 ◽  
Vol 7 (3.28) ◽  
pp. 89 ◽  
Author(s):  
Ibrahim Mohammed Sulaiman ◽  
Mustafa Mamat ◽  
Nurnadiah Zamri ◽  
Puspa Liza Ghazali
Keyword(s):  
Numerical Methods ◽  
Numerical Method ◽  
Nonlinear Equations ◽  
Computational Cost ◽  
Numerical Results ◽  
Parametric Form ◽  
Solution Point ◽  
New Ideas

New ideas on numerical methods for solving fuzzy nonlinear equations have spread quickly across the globe. However, most of the methods available are based on Newton’s approach whose performance is impaired by either discontinuity or singularity of the Jacobian at the solution point. Also, the study of dual fuzzy nonlinear equations is yet to be explored by many researchers. Thus, in this paper, a numerical method to investigate the solution of dual fuzzy nonlinear equations is proposed. This method reduces the computational cost of Jacobian evaluation at every iteration. The fuzzy coefficients are presented in its parametric form. Numerical results obtained have shown that the proposed method is efficient. 

A Practical Bundle Algorithm for Nonconvex and Nonsmooth Engineering Optimization and its Numerical Implementation

2000 ◽  
Author(s):  
Hong Wang-Zhou ◽  
Yifang Zhong ◽  
Renbin Xiao ◽  
Xuan Du ◽  
Ji Zhou
Keyword(s):  
Numerical Methods ◽  
Convergence Result ◽  
Numerical Results ◽  
Bundle Methods ◽  
Bundle Method ◽  
Engineering Optimization ◽  
Numerical Implementation ◽  
Practical Engineering ◽  
Bundle Algorithm

Abstract An algorithm based on Lemarechal’s bundle method for nonsmooth and nonconvex engineering optimization is proposed. The convergence result is given and proved. The algorithm’s numerical implementation is discussed in detail. By the numerical methods proposed by this paper, most bundle methods could be used in practical engineering optimization. Finally, some numerical results are presented to show its efficiency.

Mechanical Systems With Impacts: Comparison of Several Numerical Methods

1999 ◽  
Author(s):  
C. H. Lamarque ◽  
O. Janin
Keyword(s):  
Numerical Methods ◽  
Numerical Solution ◽  
Infinite Number ◽  
Mechanical Systems ◽  
Numerical Results ◽  
Degree Of Freedom ◽  
Periodic Behavior ◽  
Numerical Tests ◽  
Runge Kutta ◽  
Theoretical Results

Abstract We study the performances of several numerical methods (Paoli-Schatzman, Newmark, Runge-Kutta) in order to compute periodic behavior of a simple one-degree-of-freedom impacting oscillator. Some theoretical results are given and numerical tests are performed. We compare mathematical and numerical results using our simple example exhibiting either finite or infinite number of impacts per period. Comparison of exact and numerical solution provides a practical order for each scheme. We conclude about the use of the different numerical methods.

Analytical and Numerical Study of the Evaporation of a Single Fuel Droplet With a Vaporized Fuel Background

2008 ◽  
Author(s):  
Mehdi Abarham ◽  
Indrek S. Wichman
Keyword(s):  
Boundary Condition ◽  
Numerical Methods ◽  
Asymptotic Analysis ◽  
Numerical Study ◽  
Droplet Evaporation ◽  
Vapor Condensation ◽  
Stage I ◽  
Fuel Vapor ◽  
Fuel Droplet ◽  
Evaporation Stage

A simplified set of equations is examined for the problem of droplet evaporation. The equations employ the Clausius-Clapeyron boundary condition for the surface fuel-vapor condensation, which is responsible for numerous interesting mathematical behaviors, including the existence of an initial condensation stage followed by the classical d2-evaporation stage. Numerical methods of analysis are used, in conjunction with asymptotic analysis of each stage: (I) condensation; (II) transition; (III) evaporation. Comparisons are made with previous experiments. A brief discussion is provided of effective droplet evaporation in partial condensation environments.

scholarly journals Two Simple Numerical Methods for the Free Boundary in One-Phase Stefan Problem

2014 ◽  
Vol 2014 ◽  
pp. 1-10
Author(s):  
Seung Hyun Kim
Keyword(s):  
Numerical Methods ◽  
Free Boundary ◽  
Stefan Problem ◽  
Quadratic Equation ◽  
Numerical Results ◽  
Surface Temperatures ◽  
Solution Surface

We present two simple numerical methods to find the free boundary in one-phase Stefan problem. The work is motivated by the necessity for better understanding of the solution surface (temperatures) near the free boundary. We formulate a log-transform function with the unfixed and fixed free boundary that has Lipschitz character near free boundary. We solve the quadratic equation in order to locate the free boundary in a time-recursive way. We also present several numerical results which illustrate a comparison to other methods.

NUMERICAL ANALYSIS OF DEGENERATE CONNECTING ORBITS FOR MAPS

2004 ◽  
Vol 14 (10) ◽  
pp. 3385-3407 ◽  
Author(s):  
WOLF-JÜRGEN BEYN ◽  
THORSTEN HÜLS ◽  
YONGKUI ZOU
Keyword(s):  
Numerical Analysis ◽  
Dynamical Systems ◽  
Numerical Methods ◽  
Error Analysis ◽  
Error Estimates ◽  
Discrete Dynamical Systems ◽  
Numerical Results ◽  
Connecting Orbits ◽  
Theoretical Results ◽  
Degenerate Cases

This paper contains a survey of numerical methods for connecting orbits in discrete dynamical systems. Special emphasis is put on degenerate cases where either the orbit loses transversality or one of its endpoints loses hyperbolicity. Numerical methods that approximate the connecting orbits by finite orbit sequences are described in detail and theoretical results on the error analysis are provided. For most of the degenerate cases we present examples and numerical results that illustrate the applicability of the methods and the validity of the error estimates.

Sign in / Sign up

Export Citation Format

Share Document