A novel stress-induced anisotropic growth model driven by nutrient diffusion: Theory, FEM implementation and applications in bio-mechanical problems

Growth and yield predictions for managed even-aged stands in British Columbia are based on TASS, an individual-tree distance-dependent growth model driven by an unusually detailed description of crown development. Because of its complexity, most applications utilize previously generated stand-level yield tables rather than running TASS directly. I have developed a differential equation approximation to the stand-level dynamics predicted by TASS that mimics the aggregate behaviour with sufficient accuracy for many practical purposes. Versions of this model, called TADAM, exist for planted coastal Douglas-fir, lodgepole pine, and white spruce. TADAM can efficiently project stand development starting from any initial conditions, and subject to any combination of thinnings. Its relative simplicity makes it suitable for embedding into landscape-level planning models and other decision support systems. It has been implemented as a C function library, as an interactive simulator running on a PDA, and as an Excel spreadsheet add-in. An example of thinning and planting density optimization is briefly described. Key words: growth and yield, stand dynamics, thinning, optimization, Pinus contorta, Picea glauca

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Richards Growth Model Driven by Multiplicative and Additive Colored Noises: Steady-State Analysis

Fluctuation and Noise Letters ◽

10.1142/s0219477520500327 ◽

2020 ◽

Vol 19 (04) ◽

pp. 2050032

Author(s):

Chaoqun Xu ◽

Sanling Yuan

Keyword(s):

Steady State ◽

Stochastic Model ◽

Growth Model ◽

Planck Equation ◽

Steady State Analysis ◽

Model Driven ◽

Fokker Planck Equation ◽

Richards Growth Model ◽

Fokker Planck ◽

State Analysis

We consider a Richards growth model (modified logistic model) driven by correlated multiplicative and additive colored noises, and investigate the effects of noises on the eventual distribution of population size with the help of steady-state analysis. An approximative Fokker–Planck equation is first derived for the stochastic model. By performing detailed theoretical analysis and numerical simulation for the steady-state solution of the Fokker–Planck equation, i.e., stationary probability distribution (SPD) of the stochastic model, we find that the correlated noises have complex effects on the statistical property of the stochastic model. Specifically, the phenomenological bifurcation may be caused by the noises. The position of extrema of the SPD depends on the model parameter and the characters of noises in different ways.

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Surface nucleation and anisotropic growth model for the dehydration of 11-aminoundecanoic acid dihydrate

Solid State Ionics ◽

10.1016/0167-2738(95)00241-w ◽

1995 ◽

Vol 78 (1-2) ◽

pp. 49-53 ◽

Cited By ~ 1

Author(s):

M Bianchet

Keyword(s):

Growth Model ◽

Anisotropic Growth ◽

Surface Nucleation ◽

Aminoundecanoic Acid

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Finite strain visco-elastic growth driven by nutrient diffusion: theory, FEM implementation and an application to the biofilm growth

Computational Mechanics ◽

10.1007/s00466-019-01708-0 ◽

2019 ◽

Vol 64 (5) ◽

pp. 1289-1301 ◽

Cited By ~ 2

Author(s):

Meisam Soleimani

Keyword(s):

Finite Strain ◽

Diffusion Theory ◽

Biofilm Growth ◽

Nutrient Diffusion

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Autonomous demand, multiple equilibria and unemployment dynamics

Journal of Economic Interaction and Coordination ◽

10.1007/s11403-020-00306-1 ◽

2020 ◽

Author(s):

Piero Ferri ◽

Fabio Tramontana

Keyword(s):

Growth Model ◽

Dynamic Process ◽

Multiple Equilibria ◽

Initial Conditions ◽

Aggregate Demand ◽

History Plays ◽

Demand And Supply ◽

Stability Properties ◽

Model Driven ◽

Heterogeneous Consumers

Abstract The paper presents a medium-run growth model driven by autonomous demand, where aggregate demand and supply interact and unemployment is present and plays different roles. In particular, it generates a feedback from supply to aggregate demand rooted in the presence of heterogeneous consumers and an uncertain environment. Two are the main consequences of this approach. The first is that multiple equilibria can be generated. The second is that equilibria may have different stability properties. In this perspective, growth becomes a dynamic process where initial conditions matter and history plays an important role.

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