A GIS-based method for predicting the location, magnitude and occurrence time of landslides using a three-dimensional deterministic model

2008 ◽  
pp. 915-922
Keyword(s):  
Deterministic Model ◽  
Three Dimensional ◽  
Occurrence Time

scholarly journals DETERMINISTIC CHAOS VERSUS STOCHASTIC OSCILLATION IN A PREY-PREDATOR-TOP PREDATOR MODEL

2011 ◽  
Vol 16 (3) ◽  
pp. 343-364 ◽  
Author(s):  
Ranjit Kumar Upadhyay ◽  
Malay Banerjee ◽  
Rana Parshad ◽  
Sharada Nandan Raw
Keyword(s):  
Deterministic Model ◽  
Driving Forces ◽  
Equilibrium Points ◽  
Chaotic Oscillation ◽  
Three Dimensional ◽  
Deterministic Chaos ◽  
Model System ◽  
Dynamical Analysis ◽  
Interior Equilibrium ◽  
Predator Model

The main objective of the present paper is to consider the dynamical analysis of a three dimensional prey-predator model within deterministic environment and the influence of environmental driving forces on the dynamics of the model system. For the deterministic model we have obtained the local asymptotic stability criteria of various equilibrium points and derived the condition for the existence of small amplitude periodic solution bifurcating from interior equilibrium point through Hopf bifurcation. We have obtained the parametric domain within which the model system exhibit chaotic oscillation and determined the route to chaos. Finally, we have shown that chaotic oscillation disappears in presence of environmental driving forces which actually affect the deterministic growth rates. These driving forces are unable to drive the system from a regime of deterministic chaos towards a stochastically stable situation. The stochastic stability results are discussed in terms of the stability of first and second order moments. Exhaustive numerical simulations are carried out to validate the analytical findings.

scholarly journals Modelling and assessment of 137-Cs and of heavy metals impact on marine ecosystems

2020 ◽  
Vol 19 ◽  
pp. 119
Author(s):  
M. Psaltaki ◽  
N. C. Markatos
Keyword(s):  
Stokes Equations ◽  
Deterministic Model ◽  
Three Dimensional ◽  
Aegean Sea ◽  
Navier Stokes ◽  
Navier Stokes Equations ◽  
Flow Heat ◽  
Local Ecosystem ◽  
Volume Method ◽  
The Impact

Modelling is an important and useful tool for predicting the behaviour and the impact of pollutants on the local ecosystem parameters. More specifically, simulation and computational methods can be used for estimating the environmental impact on marine ecosystems.The paper presents a three-dimensional general deterministic model, developed to simulate and study the time-dependent behaviour of 137Cs in marine environments. The model capabilities are demonstrated by applying it at the northeast region of the island of Lemnos, in the NE Aegean Sea, Greece. Full Navier-Stokes equations for transient, three-dimensional turbulent flow, heat and mass transfer are solved numerically. The solution method is the finite-volume method and the general CFD code in which the present model is implemented is Phoenics.

Deterministic and Stochastic Prediction of the Hydrodynamics of a Three-Dimensional Body Falling Through Water

2008 ◽  
Author(s):  
Xuemei Zhu ◽  
Yuming Liu
Keyword(s):  
Deterministic Model ◽  
Three Dimensional ◽  
Field Measurements ◽  
The Body ◽  
Statistical Prediction ◽  
Viscous Drag ◽  
Physical Parameters ◽  
Practical Applications ◽  
Characteristic Features ◽  
Six Degree Of Freedom

We investigate the dynamics of a three-dimensional mine-shaped body falling through water deterministically and stochastically. A physics-based deterministic model, MINE6D, is developed for the prediction of the six degree-of-freedom motion of the body falling freely through water. In MINE6D, the hydrodynamic load due to the added inertia effect is obtained exactly by using a boundary-element method while the viscous drag associated with flow separation and vortex shedding is modeled using a quasi-steady approach. Since the mine motion is found to be highly sensitive to varying the physical parameters such as body geometry, mass distribution, and initial releasing conditions, we develop a stochastic model using Monte-Carlo MINE6D simulation for the statistical analysis of mine motions in practical applications. The statistical prediction is compared with available field measurements both qualitatively and quantitatively. The characteristic features and dependence on physical parameters of the statistical prediction of mine motions are investigated. The present study is of importance to the prediction of mine burial in seabed and the design of mines.

Analysis of Unsteady Flow Around Airfoil of a HAWT by Vortex Method

2003 ◽  
Author(s):  
Hiroshi Imamura ◽  
Daisuke Takezaki ◽  
Masahiro Kawai ◽  
Yutaka Hasegawa ◽  
Koji Kikuyama
Keyword(s):  
Flow Field ◽  
Unsteady Flow ◽  
Deterministic Model ◽  
Three Dimensional ◽  
Flow Simulation ◽  
Simple Algorithm ◽  
Vortex Method ◽  
Vortex Methods ◽  
Outer Flow ◽  
Vortex Element

Vortex methods have features such as relatively simple algorithm, no grid-generation in flow field and lagrangian scheme which traces each vortex element concentrated in a tiny region. It is considered that the vortex methods are effective tools for the analysis of three-dimensional, incompressible and unsteady outer flow such as flow around wind turbines. Recently, vortex methods are employed as engineering tools for three-dimensional unsteady flow. In a flow simulation by vortex methods, accuracy of simulation depends chiefly on the vortex creation model on the wall and the viscous diffusion effects. However, it seems that the deterministic model to introduce the vortex element created on the wall into flow field has not yet been accomplished. In this paper, an introduction model of vortex elements from the wall into flow field is proposed. This model is based on the analogy of the consideration of boundary-layer. In this model, intensity of vortex elements created on the wall is determined by applying both no-through and no-slip boundary conditions and the diffusion height of each element created on the wall is determined dynamically. To investigate the applicability of the model, proposed method is applied to flow around impulsively started airfoil section.

Three-Dimensional Analysis of Handspring with Full Turn Vault: Deterministic Model, Coaches' Beliefs, and Judges' Scores

1998 ◽  
Vol 14 (2) ◽  
pp. 190-210 ◽  
Author(s):  
Yoshiaki Takei
Keyword(s):  
Kinetic Energy ◽  
Deterministic Model ◽  
Three Dimensional ◽  
Vertical Displacement ◽  
Angular Distance ◽  
Energy Term ◽  
Long Duration ◽  
Full Turn ◽  
Vertical Displacements ◽  
Kinetic Energy Term

The purpose of the study was to identify mechanical variables that govern successful performance of the handspring with full turn vault. Subjects were 67 male gymnasts from 25 countries performing the vault during the 1992 Olympic Games. The vaults were filmed by two 16-mm Locam II DC cameras operating at 100 Hz. Approximately 80 frames per subject were digitized for each camera view. Direct linear transformation (DLT) was used to calculate the 3-D coordinates of the digitized body points. The method of Hay and Reid (1988) was used to develop a theoretical model to identify the mechanical variables that determine linear and angular motions of the vault. Significant correlations (p< .005) indicated that the following were important determinants for success: large horizontal velocity, large horizontal kinetic energy term, and overall translational kinetic energy term at takeoff from the board; short duration, small vertical displacement of the center of gravity (CG), and small somersaulting angular distance of preflight; large vertical velocity and large vertical kinetic energy term at takeoff from the horse; and large "amplitude of postflight," that is, large horizontal and vertical displacements of CG and long duration of flight; great height of CG during the second quarter-tum in postflight; and small point deduction for landing.

scholarly journals The Application of a Three-Dimensional Deterministic Model in the Study of Debris Flow Prediction Based on the Rainfall-Unstable Soil Coupling Mechanism

Processes ◽  
2019 ◽  
Vol 7 (2) ◽  
pp. 99 ◽  
Author(s):  
Shuangshuang Qiao ◽  
Shengwu Qin ◽  
Junjun Chen ◽  
Xiuyu Hu ◽  
Zhongjun Ma
Keyword(s):  
Slope Stability ◽  
Debris Flow ◽  
Debris Flows ◽  
Deterministic Model ◽  
Regional Scale ◽  
Three Dimensional ◽  
Flow Distribution ◽  
Coupling Mechanism ◽  
Forecasting Methods ◽  
Forecasting Method

As debris flow is one of the most destructive natural disasters in many parts of the world, the assessment and management of future debris flows with proper forecasting methods are crucial for the safety of life and property. So increasing attention has been paid to the forecasting methods on debris flows. A debris flow forecasting method based on the rainfall-unstable soil coupling mechanism (R-USCM) is presented in the current study. This method is based on the debris flow formation mechanism. The density of sediment is introduced as an evaluation index to determine the susceptibility of debris flow occurrence. The forecasting method includes two phases: (1) rainfall and soil coupling and (2) runoff and unstable soil coupling. Scoops3D, a three-dimensional (3D) model for analyzing slope stability, was introduced into the debris flow forecasting method. In order to test the forecasting accuracy of this method, Jiaohe County was selected as a research area, and the serious debris flow disasters attributed to strong rainfall on 20 July 2017 were taken as the research case. By comparing the forecasting results with the debris flow distribution map for Jiaohe County, the method based on the R-USCM is feasible for forecasting debris flows at the regional scale. The application of the Scoops3D model can more reasonably analyze the slope stability than the traditional two dimensional (2D) method and improve the forecasting ability of debris flows.

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