Mathematical morphology of three-dimensional objects: the slope diagrammatic approach

1993 ◽  
Author(s):  
Pijush K. Ghosh ◽  
Robert M. Haralick
Keyword(s):  
Mathematical Morphology ◽  
Three Dimensional ◽  
Three Dimensional Objects

Mathematical Morphology in Multi-Dexel Representation

2009 ◽  
Author(s):  
Wei Zhao ◽  
Xiaoping Qian
Keyword(s):  
Mathematical Morphology ◽  
Three Dimensional ◽  
Spatial Relationship ◽  
Noise Removal ◽  
Theoretic Approach ◽  
Three Dimension ◽  
Three Dimensional Objects ◽  
Set Operations ◽  
Part Surface ◽  
Definition Of

Mathematical morphology provides a set-theoretic approach for spatial structure analysis and is particularly useful for describing the spatial relationship between a tool under motion and the part surface. However, its usage in three-dimension has so far been limited in part due to its computational complexity. This paper presents a multi-dexel based computer implementation of morphology operations. Three dimensional objects (tools and parts) are represented as collections of dexels (depth elements) in multiple directions. Morphology operations such as dilation and erosion are then converted to a series of 1D set operations in each direction. We show that our definition of multi-dexel is formal and our implementation is complete. We present our implementation results on three morphological applications: AFM image simulation, noise removal in 3D mesh, and NC path generation.

scholarly journals Fast Overlap Detection between Hard-Core Colloidal Cuboids and Spheres. The OCSI Algorithm

Algorithms ◽  
2021 ◽  
Vol 14 (3) ◽  
pp. 72
Author(s):  
Luca Tonti ◽  
Alessandro Patti
Keyword(s):  
Colloidal Particles ◽  
Dynamic Properties ◽  
Wide Spectrum ◽  
Three Dimensional ◽  
Hard Core ◽  
Detection Algorithm ◽  
Three Dimensional Objects ◽  
Aggregation Behaviour ◽  
Sphere Radius ◽  
User Friendly

Collision between rigid three-dimensional objects is a very common modelling problem in a wide spectrum of scientific disciplines, including Computer Science and Physics. It spans from realistic animation of polyhedral shapes for computer vision to the description of thermodynamic and dynamic properties in simple and complex fluids. For instance, colloidal particles of especially exotic shapes are commonly modelled as hard-core objects, whose collision test is key to correctly determine their phase and aggregation behaviour. In this work, we propose the Oriented Cuboid Sphere Intersection (OCSI) algorithm to detect collisions between prolate or oblate cuboids and spheres. We investigate OCSI’s performance by bench-marking it against a number of algorithms commonly employed in computer graphics and colloidal science: Quick Rejection First (QRI), Quick Rejection Intertwined (QRF) and a vectorized version of the OBB-sphere collision detection algorithm that explicitly uses SIMD Streaming Extension (SSE) intrinsics, here referred to as SSE-intr. We observed that QRI and QRF significantly depend on the specific cuboid anisotropy and sphere radius, while SSE-intr and OCSI maintain their speed independently of the objects’ geometry. While OCSI and SSE-intr, both based on SIMD parallelization, show excellent and very similar performance, the former provides a more accessible coding and user-friendly implementation as it exploits OpenMP directives for automatic vectorization.

scholarly journals The Effect of Material Properties on the Perceived Shape of Three-Dimensional Objects

i-Perception ◽  
2020 ◽  
Vol 11 (6) ◽  
pp. 204166952098231
Author(s):  
Masakazu Ohara ◽  
Juno Kim ◽  
Kowa Koida
Keyword(s):  
Material Properties ◽  
Regional Variation ◽  
Three Dimensional ◽  
Mean Square ◽  
Viewing Condition ◽  
Three Dimensional Objects ◽  
Transparent Objects ◽  
Dimensional Shape ◽  
Local Root ◽  
Three Dimensional Shape

Perceiving the shape of three-dimensional objects is essential for interacting with them in daily life. If objects are constructed from different materials, can the human visual system accurately estimate their three-dimensional shape? We varied the thickness, motion, opacity, and specularity of globally convex objects rendered in a photorealistic environment. These objects were presented under either dynamic or static viewing condition. Observers rated the overall convexity of these objects along the depth axis. Our results show that observers perceived solid transparent objects as flatter than the same objects rendered with opaque reflectance properties. Regional variation in local root-mean-square image contrast was shown to provide information that is predictive of perceived surface convexity.

Effects of prolonged weightlessness on mental rotation of three-dimensional objects

1993 ◽  
Vol 94 (1) ◽  
Author(s):  
Y. Matsakis ◽  
M. Lipshits ◽  
V. Gurfinkel ◽  
A. Berthoz
Keyword(s):  
Mental Rotation ◽  
Three Dimensional ◽  
Three Dimensional Objects

scholarly journals Depth-independent segmentation of macroscopic three-dimensional objects encoded in single perspectives of digital holograms

2007 ◽  
Vol 32 (10) ◽  
pp. 1229 ◽  
Author(s):  
Conor P. McElhinney ◽  
John B. McDonald ◽  
Albertina Castro ◽  
Yann Frauel ◽  
Bahram Javidi ◽  
...  
Keyword(s):  
Three Dimensional ◽  
Three Dimensional Objects ◽  
Digital Holograms

Simultaneous Determination of Steady Temperatures and Heat Fluxes on Surfaces of Three Dimensional Objects Using FEM

2001 ◽  
Author(s):  
Brian H. Dennis ◽  
George S. Dulikravich
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Heat Conduction ◽  
Three Dimensional ◽  
Heat Fluxes ◽  
Multiply Connected ◽  
Three Dimensional Objects ◽  
Solid Objects ◽  
System Solution

Abstract A finite element method (FEM) formulation is presented for the prediction of unknown steady boundary conditions in heat conduction on multiply connected three-dimensional solid objects. The present FEM formulation is capable of determining temperatures and heat fluxes on the boundaries where such quantities are unknown or inaccessible, provided such quantities are sufficiently over-specified on other boundaries. Details of the discretization, linear system solution techniques, regularization, and sample results for 3-D problems are presented.

Sign in / Sign up

Export Citation Format

Share Document