Humans use stereo and haptic distance cues to improve physical object size estimates

The geometric optics of an endoscope can be used to determine the absolute size of an object in an endoscopic field without knowing the actual distance from the object. This study explores the accuracy of a technique that estimates absolute object size from endoscopic images. Quantitative endoscopy involves calibrating a rigid endoscope to produce size estimates from 2 images taken with a known traveled distance between the images. The heights of 12 samples, ranging in size from 0.78 to 11.80 mm, were estimated with this calibrated endoscope. Backup distances of 5 mm and 10 mm were used for comparison. The mean percent error for all estimated measurements when compared with the actual object sizes was 1.12%. The mean errors for 5-mm and 10-mm backup distances were 0.76% and 1.65%, respectively. The mean errors for objects <2 mm and ≥2 mm were 0.94% and 1.18%, respectively. Quantitative endoscopy estimates endoscopic image size to within 5% of the actual object size. This method remains promising for quantitatively evaluating object size from endoscopic images. It does not require knowledge of the absolute distance of the endoscope from the object, rather, only the distance traveled by the endoscope between images.

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Neural representations of haptic object size in the human brain revealed by multivoxel fMRI patterns

Journal of Neurophysiology ◽

10.1152/jn.00160.2020 ◽

2020 ◽

Vol 124 (1) ◽

pp. 218-231 ◽

Cited By ~ 1

Author(s):

Francesca Perini ◽

Thomas Powell ◽

Simon J. Watt ◽

Paul E. Downing

Keyword(s):

Human Brain ◽

Functional Mri ◽

Object Size ◽

Motor Tasks ◽

Neural Basis ◽

Neural Representations ◽

The World ◽

Haptic Object ◽

Size Estimates

Our understanding of the neural basis of haptics (perceiving the world through touch) remains incomplete. We used functional MRI to study human haptic judgments of object size, which require integrating multiple afferent signals. Multivoxel pattern analyses identified intraparietal and prefrontal regions that encode size haptically in a metric and hand-invariant fashion. Effector-independent haptic size estimates are useful on their own and in combination with other sensory estimates for a variety of perceptual and motor tasks.

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Does grasping capacity influence object size estimates? It depends on the context

Attention Perception & Psychophysics ◽

10.3758/s13414-017-1344-3 ◽

2017 ◽

Vol 79 (7) ◽

pp. 2117-2131 ◽

Cited By ~ 2

Author(s):

Elizabeth S. Collier ◽

Rebecca Lawson

Keyword(s):

Object Size ◽

Size Estimates

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Effects of display media type, ambient lighting, viewing distance, viewing offset, object type, and object size on large-screen display legibility

PsycEXTRA Dataset ◽

10.1037/e578862012-008 ◽

2010 ◽

Author(s):

Jake Wetzel ◽

Angie Hernandez

Keyword(s):

Viewing Distance ◽

Object Size ◽

Object Type ◽

Large Screen ◽

Media Type ◽

Ambient Lighting

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Mean Object Size Considering Average Waiting Latency in M/BP/1 System

SSRN Electronic Journal ◽

10.2139/ssrn.3724774 ◽

2020 ◽

Author(s):

Y.J. Lee

Keyword(s):

Object Size

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Estimating the population size of people who inject drugs in Ho Chi Minh City, Vietnam: A two-survey capture-recapture exercise (Preprint)

10.2196/preprints.16459 ◽

2019 ◽

Author(s):

Abu Abdul-Quader

Keyword(s):

Population Size ◽

Illicit Drugs ◽

People Who Inject Drugs ◽

Care Service ◽

Ho Chi Minh City ◽

Size Estimation ◽

Population Size Estimates ◽

Capture Recapture ◽

The City ◽

Size Estimates

BACKGROUND Population size estimation of people who inject drugs (PWID) in Ho Chi Minh City (HCMC), Vietnam relied on the UNAIDS Estimation and Projection Package and reports from the city police department. The two estimates vary widely. OBJECTIVE To estimate the population size of people who inject drugs in Ho Chi Minh City, Vietnam METHODS Using Respondent-driven sampling (RDS), we implemented two-source capture-recapture method to estimate the population size of PWID in HCMC in 2017 in 7 out of 24 districts. The study included men or women aged at least 18 years who reported injecting illicit drugs in the last 90 days and who had lived in the city the past six months. We calculated two sets of size estimates, the first assumed that all participants in each survey round resided in the district where the survey was conducted, the second, used the district of residence as reported by the participant. District estimates were summed to obtain an aggregate estimate for the seven districts. To calculate the city total, we weighted the population size estimates for each district by the inverse of the stratum specific sampling probabilities. RESULTS The first estimate resulted in a population size of 19,155 (95% CI: 17,006–25,039). The second one generated a smaller population size estimate of 12,867 (95% CI: 11,312–17,393). CONCLUSIONS The two-survey capture-recapture exercise provided two disparate estimates of PWID in HCMC. For planning HIV prevention and care service needs among PWID in HCMC, both estimates may need to be taken into consideration together with size estimates from other sources.

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Meaning

10.1093/oso/9780198714057.003.0012 ◽

2017 ◽

Author(s):

Richard Healey

Keyword(s):

Quantum Theory ◽

Physical Object ◽

Quantum Fields ◽

Conceptual Content ◽

Classical Physics ◽

Physical Context

Novel quantum concepts acquire content not by representing new beables but through material-inferential relations between claims about them and other claims. Acceptance of quantum theory modifies other concepts in accordance with a pragmatist inferentialist account of how claims acquire content. Quantum theory itself introduces no new beables, but accepting it affects the content of claims about classical magnitudes and other beables unknown to classical physics: the content of a magnitude claim about a physical object is a function of its physical context in a way that eludes standard pragmatics but may be modeled by decoherence. Leggett’s proposed test of macro-realism illustrates this mutation of conceptual content. Quantum fields are not beables but assumables of a quantum theory we use to make claims about particles and non-quantum fields whose denotational content may also be certified by models of decoherence.

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Silence

10.1093/oso/9780198824589.003.0018 ◽

2018 ◽

Author(s):

Andrew Steane

Keyword(s):

Physical Object ◽

Spiritual Exercise

This brief chapter presents a spiritual exercise, which is to contemplate an ordinary physical object in a way that does not involve assessing it but involves merely being in its presence and allowing it to impinge~on~one.

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Extremely Gusty Winds from a Viewpoint of Aerodynamic Force

The Oxford Handbook of Non-Synoptic Wind Storms ◽

10.1093/oxfordhb/9780190670252.013.5 ◽

2020 ◽

Author(s):

Junji Maeda ◽

Takashi Takeuchi ◽

Eriko Tomokiyo ◽

Yukio Tamura

Keyword(s):

Wind Speed ◽

Wind Tunnel ◽

Rise Time ◽

Aerodynamic Force ◽

Step Function ◽

Object Size ◽

Aerodynamic Forces ◽

Wind Force ◽

Wind Observation

To quantitatively investigate a gusty wind from the viewpoint of aerodynamic forces, a wind tunnel that can control the rise time of a step-function-like gust was devised and utilized. When the non-dimensional rise time, which is calculated using the rise time of the gusty wind, the wind speed, and the size of an object, is less than a certain value, the wind force is greater than under the corresponding steady wind. Therefore, this wind force is called the “overshoot wind force” for objects the size of orbital vehicles in an actual wind observation. The finding of the overshoot wind force requires a condition of the wind speed recording specification and depends on the object size and the gusty wind speed.

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