Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

Torsion of Noncircular Members01:16

Torsion of Noncircular Members

Circular shafts undergoing torsional stress maintain their cross-sectional integrity due to their axisymmetric nature. This symmetry ensures an even distribution of stress, allowing the shaft to withstand torsion without distorting. In contrast, square bars, lacking this axial symmetry, experience significant distortion across their cross-sections when subjected to torsion, with the exception of along their diagonals and at lines connecting midpoints. A detailed examination of a cubic element...
Torsion in Vector Calculus01:20

Torsion in Vector Calculus

A toy train ascending a winding track that curves and tilts offers an intuitive view of torsion, a key geometric concept in the study of space curves. While curvature measures how sharply a path bends, torsion captures how the path twists out of the plane of bending. This twisting behavior is crucial in understanding three-dimensional motion and is precisely described using the Frenet–Serret framework.At each point along a space curve, the Frenet–Serret frame consists of three orthogonal unit...
Thin-Walled Hollow Shafts01:15

Thin-Walled Hollow Shafts

In analyzing a thin-walled hollow shaft subjected to torsional loading, a segment with width dx is isolated for examination. Despite its equilibrium state, this segment faces torsional shearing forces at its ends. These forces are quantitatively described by the product of the longitudinal shearing stress on the segment's minor surface and the area of this surface, leading to the concept of shear flow. This shear flow is consistent throughout the structure, indicating a uniform distribution of...
Deformation in a Circular Shaft01:10

Deformation in a Circular Shaft

One of the distinctive characteristics of circular shafts is their ability to maintain their cross-sectional integrity under torsion. In other words, each cross-section continues to exist as a flat, unaltered entity, simply rotating like a solid, rigid slab. To understand the distribution of shearing stress within such a shaft, consider a cylindrical section inside this circular shaft. This section has a length of L and a radius of R, with one end fixed. The radius of the cylindrical section is...
Accuracy, limits, and approximation01:28

Accuracy, limits, and approximation

Accuracy, limits, and approximations are common in many fields, especially in engineering calculations. These concepts are imperative for ensuring that a given value is as close as possible to its true value.
Accuracy is defined as the closeness of the measured value to the true or actual value. In engineering mechanics, repeated measurements are taken during theoretical or experimental analyses to ensure that the result is precise and accurate.
The accuracy of any solution is based on the...
Tangent Planes to Surfaces01:19

Tangent Planes to Surfaces

In multivariable calculus, the concept of a tangent plane plays a central role in approximating curved surfaces. When dealing with a surface defined by a function of two variables, such as z = f(x, y), the tangent plane at a given point provides the best linear approximation to the surface near that point. This local linearization allows complex, nonlinear geometries to be treated using simpler, planar models.The construction of the tangent plane involves taking vertical slices of the surface...

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

The impact of a perceptual and adaptive learning module on transoesophageal echocardiography interpretation by anaesthesiology residents.

British journal of anaesthesia·2017
Same author

Poor predictive value of contemporary bleeding risk scores during long-term treatment of venous thromboembolism. A multicentre retrospective cohort study.

Thrombosis and haemostasis·2014
Same author

Can IVUS-virtual histology improve outcomes of percutaneous carotid treatment?

The Journal of cardiovascular surgery·2009
Same author

Volume measurement by CARTO compared with cardiac magnetic resonance.

Europace : European pacing, arrhythmias, and cardiac electrophysiology : journal of the working groups on cardiac pacing, arrhythmias, and cardiac cellular electrophysiology of the European Society of Cardiology·2006
Same author

Contour curvature polarity and surface interpolation.

Vision research·2005
Same author

[Check-list for inspection in banks].

Giornale italiano di medicina del lavoro ed ergonomia·2004

Related Experiment Video

Updated: Jul 6, 2026

Method to Measure Tone of Axial and Proximal Muscle
10:41

Method to Measure Tone of Axial and Proximal Muscle

Published on: December 14, 2011

Approximation, torsion, and amodally-completed surfaces.

C Fantoni1, W Gerbino, P J Kellman

  • 1Department of Psychology and B.R.A.I.N. Center for Neuroscience, University of Trieste, via Sant'Anastasio 12, 34134 Trieste, Italy. fantoni@psico.units.it

Vision Research
|April 1, 2008
PubMed
Summary
This summary is machine-generated.

Perception of surface slant is altered by occlusion. When surfaces are partially hidden, their slant is underestimated (assimilation), but when fully visible, slant is overestimated (contrast). This visual illusion impacts how we perceive 3D shapes.

More Related Videos

Biaxial Mechanical Characterizations of Atrioventricular Heart Valves
11:00

Biaxial Mechanical Characterizations of Atrioventricular Heart Valves

Published on: April 9, 2019

Related Experiment Videos

Last Updated: Jul 6, 2026

Method to Measure Tone of Axial and Proximal Muscle
10:41

Method to Measure Tone of Axial and Proximal Muscle

Published on: December 14, 2011

Biaxial Mechanical Characterizations of Atrioventricular Heart Valves
11:00

Biaxial Mechanical Characterizations of Atrioventricular Heart Valves

Published on: April 9, 2019

Area of Science:

  • Visual Perception
  • Computational Neuroscience
  • Psychophysics

Background:

  • The perception of surface slant, particularly in stereoscopic displays, is influenced by contextual cues.
  • Amodal completion, the visual system's ability to perceive occluded surfaces, plays a role in surface perception.
  • Illusory contours and occluders can significantly alter perceived depth and slant.

Purpose of the Study:

  • To investigate the phenomenon of slant assimilation and contrast in stereoscopic vision.
  • To determine the role of occluders and amodal completion in modulating perceived surface slant.
  • To examine the influence of surface torsion and display conditions on slant perception accuracy.

Main Methods:

  • Three experiments utilized stereoscopic displays simulating frontoparallel and slanted rectangular patches.
  • Conditions included displays with and without occluders to manipulate amodal completion.
  • Two primary methods were employed: slant matching and speeded classification of twist direction.

Main Results:

  • Slant assimilation (underestimation) was observed in displays with occluders, while slant contrast (overestimation) occurred in displays without occluders.
  • A component of slant assimilation was directly attributable to the mere presence of an occluder, independent of full amodal completion.
  • Perceptual performance, particularly twist classification, was impaired when amodal completion was hindered but more so when surface patches were completed.

Conclusions:

  • The visual system employs approximation over interpolation for amodal completion under limiting conditions to minimize torsion.
  • Slant assimilation is reduced with increasing twist angles, suggesting a limit to the visual system's ability to form smooth, amodal surfaces with torsion.
  • Occlusion and the resulting amodal completion are critical factors in the accurate perception of surface slant and 3D geometry.