Perception of soft materials relies on physics-based object representations: Behavioral and computational evidence

When encountering objects, we readily perceive not only low-level properties (e.g., color and orientation), but also seemingly higher-level ones--including aspects of physics (e.g., mass). Perhaps nowhere is this contrast more salient than in the perception of soft materials such as cloths: the dynamics of these objects (including how their three-dimensional forms vary) are determined by their physical properties such as stiffness, elasticity, and mass. Here we hypothesize that the perception of cloths and their physical properties must involve not only image statistics, but also abstract object representations that incorporate "intuitive physics". We provide behavioral and computational evidence for this hypothesis. We find that humans can visually match the stiffness of cloths with unfamiliar textures from the way they undergo natural transformations (e.g. flapping in the wind) across different scenarios. A computational model that casts cloth perception as mental physics simulation explains important aspects of this behavior.

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A general three-dimensional computational model for nonlinear composite structures and materials

10.2514/6.1977-360 ◽

1977 ◽

Cited By ~ 1

Author(s):

E. STANTON

Keyword(s):

Computational Model ◽

Composite Structures ◽

Three Dimensional ◽

Nonlinear Composite

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COPPER ALLOY No. 120

Alloy Digest ◽

10.31399/asm.ad.cu0263 ◽

1972 ◽

Vol 21 (12) ◽

Keyword(s):

Electrical Conductivity ◽

Corrosion Resistance ◽

Shear Strength ◽

Physical Properties ◽

Tensile Properties ◽

Copper Alloy ◽

Heat Treating ◽

Residual Phosphorus ◽

Low Level

Abstract COPPER No. 120 is a phosphorus deoxidized copper in which the residual phosphorus is maintained at a low level to acheive a good electrical conductivity. This datasheet provides information on composition, physical properties, hardness, elasticity, tensile properties, and shear strength as well as fatigue. It also includes information on corrosion resistance as well as forming, heat treating, machining, and joining. Filing Code: Cu-263. Producer or source: Copper and copper alloy mills.

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Urban network of China from the perspective of population mobility: Three-dimensional co-occurrence of nodes and links

Environment and Planning A Economy and Space ◽

10.1177/0308518x21997818 ◽

2021 ◽

pp. 0308518X2199781

Author(s):

Xinyue Luo ◽

Mingxing Chen

Keyword(s):

Three Dimensional ◽

Geographical Distance ◽

Two Dimensional ◽

Population Mobility ◽

Urban Network ◽

Urban Networks ◽

Low Level ◽

Medium Level ◽

High Level ◽

External Connections

The nodes and links in urban networks are usually presented in a two-dimensional(2D) view. The co-occurrence of nodes and links can also be realized from a three-dimensional(3D) perspective to make the characteristics of urban network more intuitively revealed. Our result shows that the external connections of high-level cities are mainly affected by the level of cities(nodes) and less affected by geographical distance, while medium-level cities are affected by the interaction of the level of cities(nodes) and geographical distance. The external connections of low-level cities are greatly restricted by geographical distance.

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A Computational Analysis of Flow Field in Twin-Track Subway Tunnel to Improve Air Quality

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.319.599 ◽

2013 ◽

Vol 319 ◽

pp. 599-604

Author(s):

Makhsuda Juraeva ◽

Kyung Jin Ryu ◽

Sang Hyun Jeong ◽

Dong Joo Song

Keyword(s):

Air Quality ◽

Computational Model ◽

Stokes Equations ◽

Ventilation System ◽

Three Dimensional ◽

Aerodynamic Characteristics ◽

Navier Stokes ◽

Subway Tunnel ◽

Air Supply ◽

And Performance

A computational model of existing Seoul subway tunnelwas analyzed in this research. The computational model was comprised of one natural ventilationshaft, two mechanical ventilationshafts, one mechanical airsupply, a twin-track tunnel, and a train. Understanding the flow pattern of the train-induced airflow in the tunnel was necessary to improve ventilation performance. The research objective wasto improve the air quality in the tunnel by investigating train-induced airflow in the twin-track subway tunnel numerically. The numerical analysis characterized the aerodynamic behavior and performance of the ventilation system by solving three-dimensional turbulent Reynolds-averaged Navier-Stokes equations. ANSYS CFX software was used for the computations. The ventilation and aerodynamic characteristics in the tunnel were investigated by analyzing the mass flowrateat the exits of the ventilation mechanicalshafts. As the train passed the mechanical ventilation shafts, the amount of discharged-air in the ventilationshafts decreased rapidly. The air at the exits of the ventilation shafts was gradually recovered with time, after the train passed the ventilation shafts. The developed mechanical air-supply for discharging dusty air and supplying clean airwas investigated.The computational results showed that the developed mechanical air-supplycould improve the air quality in the tunnel.

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Computational Model for Cell Migration in Three-Dimensional Matrices

Biophysical Journal ◽

10.1529/biophysj.105.060723 ◽

2005 ◽

Vol 89 (2) ◽

pp. 1389-1397 ◽

Cited By ~ 174

Author(s):

Muhammad H. Zaman ◽

Roger D. Kamm ◽

Paul Matsudaira ◽

Douglas A. Lauffenburger

Keyword(s):

Cell Migration ◽

Computational Model ◽

Three Dimensional

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Modelling human skull growth: a validated computational model

Journal of The Royal Society Interface ◽

10.1098/rsif.2017.0202 ◽

2017 ◽

Vol 14 (130) ◽

pp. 20170202 ◽

Cited By ~ 11

Author(s):

Joseph Libby ◽

Arsalan Marghoub ◽

David Johnson ◽

Roman H. Khonsari ◽

Michael J. Fagan ◽

...

Keyword(s):

Computational Model ◽

Three Dimensional ◽

Basic Knowledge ◽

Fe Model ◽

Adult Size ◽

Fe Method ◽

Percentage Difference ◽

Skull Growth

During the first year of life, the brain grows rapidly and the neurocranium increases to about 65% of its adult size. Our understanding of the relationship between the biomechanical forces, especially from the growing brain, the craniofacial soft tissue structures and the individual bone plates of the skull vault is still limited. This basic knowledge could help in the future planning of craniofacial surgical operations. The aim of this study was to develop a validated computational model of skull growth, based on the finite-element (FE) method, to help understand the biomechanics of skull growth. To do this, a two-step validation study was carried out. First, an in vitro physical three-dimensional printed model and an in silico FE model were created from the same micro-CT scan of an infant skull and loaded with forces from the growing brain from zero to two months of age. The results from the in vitro model validated the FE model before it was further developed to expand from 0 to 12 months of age. This second FE model was compared directly with in vivo clinical CT scans of infants without craniofacial conditions ( n = 56). The various models were compared in terms of predicted skull width, length and circumference, while the overall shape was quantified using three-dimensional distance plots. Statistical analysis yielded no significant differences between the male skull models. All size measurements from the FE model versus the in vitro physical model were within 5%, with one exception showing a 7.6% difference. The FE model and in vivo data also correlated well, with the largest percentage difference in size being 8.3%. Overall, the FE model results matched well with both the in vitro and in vivo data. With further development and model refinement, this modelling method could be used to assist in preoperative planning of craniofacial surgery procedures and could help to reduce reoperation rates.

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Morphological traits of the development of the skin and wool cover in sheep of Prikatunsky meat and wool type

Glavnyj zootehnik (Head of Animal Breeding) ◽

10.33920/sel-03-2110-07 ◽

2021 ◽

pp. 60-68

Author(s):

I. I. Dmitrik ◽

G. V. Zavgorodnyaya ◽

M. I. Pavlova ◽

N. A. Podkorytov

Keyword(s):

Physical Properties ◽

Morphological Traits ◽

Age Groups ◽

Body Side ◽

Low Level ◽

Research Material ◽

High Level ◽

Significant Factors

A large number of works are devoted to the development of the skin and hair cover of sheep, depending on their breed affiliation, age, feeding conditions and housing. The authors point out that along with other conditions the quality of wool and wool clip is greatly influenced by the conditions of the feeding of animals. A high level of feeding increases the wool clip and improves the quality of the wool and vice versa a low level reduces, causes thinning and worsens other physical properties of the wool. As is known, one of the significant factors that determine the increase in wool clip is the size of the animal and, consequently, the total area of the skin. The purpose of the research was to investigate the morphological traits of the development of the skin and wool cover in sheep of Prikatunsky meat and wool type. The research material was wool samples from four topographic areas of the animal’s body (side/thigh/back/belly) and skin (side) of different sex and age groups, selected from the animals of the studied groups. In the course of research, the quality of wool and indicators of the histostructure of the skin of Prikatunsky meat and wool type of sheep have been investigated. In terms of thick-haired of wool, replacement rams and gimbers of Prikatunsky meat and wool type of sheep were superior by 4,82 pcs. per mm² or 19,0 % and 4,41 pcs. per mm² or 15,8 % of adult animals, respectively. Balance secondary follicles/primary follicles in young animals were higher by 10,3 and 17,3 % compared to breeding rams and ewes. The wool of the replacement young animals was thinner by 7,28 and 4,78 microns and they were more thick-haired. The obtained data will be used in the mating campaign when mating program rams in order to improve the sheep of Prikatunsky meat and wool type.

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Study of a temperature gradient metamorphism of snow from 3-D images: time evolution of microstructures, physical properties and their associated anisotropy

The Cryosphere ◽

10.5194/tc-8-2255-2014 ◽

2014 ◽

Vol 8 (6) ◽

pp. 2255-2274 ◽

Cited By ~ 27

Author(s):

N. Calonne ◽

F. Flin ◽

C. Geindreau ◽

B. Lesaffre ◽

S. Rolland du Roscoat

Keyword(s):

Temperature Gradient ◽

Physical Properties ◽

Time Evolution ◽

Three Dimensional ◽

Vertical Direction ◽

Large Set ◽

Correlation Lengths ◽

Snow Properties ◽

Cold Room ◽

Anisotropy Coefficients

Abstract. We carried out a study to monitor the time evolution of microstructural and physical properties of snow during temperature gradient metamorphism: a snow slab was subjected to a constant temperature gradient in the vertical direction for 3 weeks in a cold room, and regularly sampled in order to obtain a series of three-dimensional (3-D) images using X-ray microtomography. A large set of properties was then computed from this series of 3-D images: density, specific surface area, correlation lengths, mean and Gaussian curvature distributions, air and ice tortuosities, effective thermal conductivity, and intrinsic permeability. Whenever possible, specific attention was paid to assess these properties along the vertical and horizontal directions, and an anisotropy coefficient defined as the ratio of the vertical over the horizontal values was deduced. The time evolution of these properties, as well as their anisotropy coefficients, was investigated, showing the development of a strong anisotropic behavior during the experiment. Most of the computed physical properties of snow were then compared with two analytical estimates (self-consistent estimates and dilute beds of spheroids) based on the snow density, and the size and anisotropy of the microstructure through the correlation lengths. These models, which require only basic microstructural information, offer rather good estimates of the properties and anisotropy coefficients for our experiment without any fitting parameters. Our results highlight the interplay between the microstructure and physical properties, showing that the physical properties of snow subjected to a temperature gradient cannot be described accurately using only isotropic parameters such as the density and require more refined information. Furthermore, this study constitutes a detailed database on the evolution of snow properties under a temperature gradient, which can be used as a guideline and a validation tool for snow metamorphism models at the micro- or macroscale.

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