The “Dead Leaves” model

2016 ◽  
pp. 205-218
Keyword(s):  
Dead Leaves Model ◽  
The Dead

scholarly journals A connection between the volume fractions of the Stienen model and the dead leaves model

2007 ◽  
Vol 39 (1) ◽  
pp. 41-52
Author(s):  
Marianne Månsson
Keyword(s):  
Volume Fraction ◽  
Equal Size ◽  
Convex Shape ◽  
Volume Fractions ◽  
Speed Distribution ◽  
Centrally Symmetric ◽  
Dead Leaves Model ◽  
The Dead ◽  
Spherical Grains

The volume fraction of the intact grains of the dead leaves model with spherical grains of equal size is 2−d in d dimensions. This is the volume fraction of the original Stienen model. Here we consider some variants of these models: the dead leaves model with grains of a fixed convex shape and possibly random sizes and random orientations, and a generalisation of the Stienen model with convex grains growing at random speeds. The main result of this paper is that if the radius distribution in the dead leaves model equals the speed distribution in the Stienen model, then the volume fractions of the two models are the same in this case also. Furthermore, we show that for grains of a fixed shape and orientation, centrally symmetric sets give the highest volume fraction, while simplices give the lowest. If the grains are randomly rotated, then the volume fraction achieves its highest value only for spheres.

scholarly journals SOME DENSE RANDOM PACKINGS GENERATED BY THE DEAD LEAVES MODEL

2019 ◽  
Vol 38 (1) ◽  
pp. 3
Author(s):  
Dominique Jeulin
Keyword(s):  
Correlation Function ◽  
Pair Correlation Function ◽  
Random Media ◽  
Volume Fraction ◽  
Pair Correlation ◽  
Sequential Model ◽  
Dead Leaves Model ◽  
The Dead ◽  
Dense Packings ◽  
Random Packings

The intact grains of the dead leaves model enables us to generate random media with non overlapping grains. Using the time non homogeneous sequential model with convex grains, theoretically very dense packings can be generated, up to a full covering of space. For these models, the theoretical volume fraction, the size distribution of grains, and the pair correlation function of centers of grains are given.

scholarly journals A connection between the volume fractions of the Stienen model and the dead leaves model

2007 ◽  
Vol 39 (01) ◽  
pp. 41-52
Author(s):  
Marianne Månsson
Keyword(s):  
Volume Fraction ◽  
Equal Size ◽  
Convex Shape ◽  
Volume Fractions ◽  
Speed Distribution ◽  
Centrally Symmetric ◽  
Dead Leaves Model ◽  
The Dead ◽  
Spherical Grains

The volume fraction of the intact grains of the dead leaves model with spherical grains of equal size is 2−dinddimensions. This is the volume fraction of the original Stienen model. Here we consider some variants of these models: the dead leaves model with grains of a fixed convex shape and possibly random sizes and random orientations, and a generalisation of the Stienen model with convex grains growing at random speeds. The main result of this paper is that if the radius distribution in the dead leaves model equals the speed distribution in the Stienen model, then the volume fractions of the two models are the same in this case also. Furthermore, we show that for grains of a fixed shape and orientation, centrally symmetric sets give the highest volume fraction, while simplices give the lowest. If the grains are randomly rotated, then the volume fraction achieves its highest value only for spheres.

scholarly journals The dead leaves model: a general tessellation modeling occlusion

2006 ◽  
Vol 38 (1) ◽  
pp. 31-46 ◽  
Author(s):  
Charles Bordenave ◽  
Yann Gousseau ◽  
François Roueff
Keyword(s):  
Mathematical Morphology ◽  
Visual Images ◽  
Compact Sets ◽  
Essential Ingredient ◽  
Closed Sets ◽  
Random Closed Sets ◽  
Random Tessellation ◽  
Dead Leaves Model ◽  
The Dead

In this article, we study a particular example of general random tessellation, the dead leaves model. This model, first studied by the mathematical morphology school, is defined as a sequential superimposition of random closed sets, and provides the natural tool to study the occlusion phenomenon, an essential ingredient in the formation of visual images. We generalize certain results of G. Matheron and, in particular, compute the probability of n compact sets being included in visible parts. This result characterizes the distribution of the boundary of the dead leaves tessellation.

scholarly journals The dead leaves model: a general tessellation modeling occlusion

2006 ◽  
Vol 38 (01) ◽  
pp. 31-46 ◽  
Author(s):  
Charles Bordenave ◽  
Yann Gousseau ◽  
François Roueff
Keyword(s):  
Mathematical Morphology ◽  
Visual Images ◽  
Compact Sets ◽  
Essential Ingredient ◽  
Closed Sets ◽  
Random Closed Sets ◽  
Random Tessellation ◽  
Dead Leaves Model ◽  
The Dead

In this article, we study a particular example of general random tessellation, the dead leaves model. This model, first studied by the mathematical morphology school, is defined as a sequential superimposition of random closed sets, and provides the natural tool to study the occlusion phenomenon, an essential ingredient in the formation of visual images. We generalize certain results of G. Matheron and, in particular, compute the probability of n compact sets being included in visible parts. This result characterizes the distribution of the boundary of the dead leaves tessellation.

An Alternative Method for Identifying a Failed Engine in Twin-Engine Propeller Aircraft

2020 ◽  
Vol 10 (2) ◽  
pp. 103-111
Author(s):  
Andrey K. Babin ◽  
Andrew R. Dattel ◽  
Margaret F. Klemm
Keyword(s):  
Human Error ◽  
Flight Simulator ◽  
Traditional Group ◽  
Aircraft Accidents ◽  
Alternative Method ◽  
Indicator Group ◽  
Group A ◽  
The Dead ◽  
Engine Failure ◽  
And Performance

Abstract. Twin-engine propeller aircraft accidents occur due to mechanical reasons as well as human error, such as misidentifying a failed engine. This paper proposes a visual indicator as an alternative method to the dead leg–dead engine procedure to identify a failed engine. In total, 50 pilots without a multi-engine rating were randomly assigned to a traditional (dead leg–dead engine) or an alternative (visual indicator) group. Participants performed three takeoffs in a flight simulator with a simulated engine failure after rotation. Participants in the alternative group identified the failed engine faster than the traditional group. A visual indicator may improve pilot accuracy and performance during engine-out emergencies and is recommended as a possible alternative for twin-engine propeller aircraft.

Sign in / Sign up

Export Citation Format

Share Document