scholarly journals Cortical idiosyncrasies predict the perception of object size

2016 ◽  
Vol 7 (1) ◽  
Author(s):  
Christina Moutsiana ◽  
Benjamin de Haas ◽  
Andriani Papageorgiou ◽  
Jelle A. van Dijk ◽  
Annika Balraj ◽  
...  
Keyword(s):  
Object Size

Extremely Gusty Winds from a Viewpoint of Aerodynamic Force

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.

Automatic Method for Measuring Object Size Using 3D Camera

2021 ◽  
Author(s):  
Cuong Vo-Le ◽  
Pham Van Muoi ◽  
Nguyen Hong Son ◽  
Nguyen Van San ◽  
Vu Khac Duong ◽  
...  
Keyword(s):  
Object Size ◽  
Automatic Method ◽  
3D Camera

Visual perception of changing size: The effect of object size

1979 ◽  
Vol 19 (10) ◽  
pp. 1093-1104 ◽  
Author(s):  
K.I. Beverley ◽  
D. Regan
Keyword(s):  
Visual Perception ◽  
Object Size

Perception-Action Coupling in Grasping of Children with Down Syndrome

2001 ◽  
Vol 18 (4) ◽  
pp. 451-457 ◽  
Author(s):  
Geert J.P. Savelsbergh ◽  
John van der Kamp ◽  
Walter E. Davis
Keyword(s):  
Down Syndrome ◽  
Body Size ◽  
Random Order ◽  
Object Size ◽  
Children With Down Syndrome ◽  
Hand Size ◽  
Dimensionless Ratio ◽  
Action Coupling ◽  
Perception Action

Twenty-one children with Down syndrome (DS) and 20 without disability, ages 3 to 11 years, completed the experiment in which they were asked to grasp and lift cardboard cubes of different sizes (2.2 to 16.2 cm in width). Three conditions were used: (a) increasing the size from the smallest to the largest cube, (b) decreasing the size from the largest to the smallest, and (c) a random order of sizes. Children with DS were found to have smaller hand sizes in comparison to age-matched children without DS. In addition, the shift from one-handed to two-handed grasping appeared at a smaller cube size for children with DS than for children without DS. However, when the dimensionless ratio between object size and hand size was considered, the differences between groups disappeared, indicating that the differences in grasping patterns between children with and without DS can be attributed to differences in body size.

A New View on Grasping

Motor Control ◽  
1999 ◽  
Vol 3 (3) ◽  
pp. 237-271 ◽  
Author(s):  
Jeroen B.J. Smeets ◽  
Eli Brenner
Keyword(s):  
Surface Roughness ◽  
Visual Information ◽  
Experimental Studies ◽  
Movement Speed ◽  
Object Size ◽  
Extensive Review ◽  
Minimum Jerk ◽  
Alternative Description ◽  
Position And Orientation ◽  
Shape And Size

Reaching out for an object is often described as consisting of two components that are based on different visual information. Information about the object's position and orientation guides the hand to the object, while information about the object's shape and size determines how the fingers move relative to the thumb to grasp it. We propose an alternative description, which consists of determining suitable positions on the object—on the basis of its shape, surface roughness, and so on—and then moving one's thumb and fingers more or less independently to these positions. We modeled this description using a minimum-jerk approach, whereby the finger and thumb approach their respective target positions approximately orthogonally to the surface. Our model predicts how experimental variables such as object size, movement speed, fragility, and required accuracy will influence the timing and size of the maximum aperture of the hand. An extensive review of experimental studies on grasping showed that the predicted influences correspond to human behavior.

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