scholarly journals Rotating Snakes Illusion—Quantitative Analysis Reveals a Region in Luminance Space With Opposite Illusory Rotation

i-Perception ◽  
2017 ◽  
Vol 8 (1) ◽  
pp. 204166951769177 ◽  
Author(s):  
Lea Atala-Gérard ◽  
Michael Bach
Keyword(s):  
Quantitative Analysis ◽  
Opposite Direction ◽  
White Light ◽  
Rotation Speed ◽  
Quantitative Measurements

The Rotating Snakes Illusion employs patterns with repetitive asymmetric luminance steps forming a “snake wheel.” In the underlying luminance sequence {black, dark grey, white, light grey}, coded as {0, g1, 100, g2}, we varied g1 and g2 and measured illusion strength via nulling: Saccades were performed next to a “snake wheel” that rotated physically; observers adjusted rotation until a stationary percept obtained. Observers performed the perceptual nulling of the seeming rotation reliably. Typical settings for (g1, g2), measured from images by Kitaoka, are around (20%, 60%). Indeed, we found a marked illusion in the region (g1≈{0%–25%}, g2≈{20%–75%}) with a rotation speed of ≈1°/s. Surprisingly, we detected a second “island” around (70%, 95%) with opposite direction of the illusory rotation and weaker illusion. Our quantitative measurements of illusion strength confirmed the optimal luminance choices of the standard snake wheel and, unexpectedly, revealed an opposite rotation illusion.

Comparative and quantitative analysis of white light-emitting diodes and other lamps used for home illumination

2015 ◽  
Vol 54 (1) ◽  
pp. 014104 ◽  
Author(s):  
Rero Marques Rubinger ◽  
Edna Raimunda da Silva ◽  
Daniel Zaroni Pinto ◽  
Carla Patrícia Lacerda Rubinger ◽  
Adhimar Flávio Oliveira ◽  
...  
Keyword(s):  
Quantitative Analysis ◽  
White Light ◽  
Light Emitting Diodes ◽  
Light Emitting ◽  
White Light Emitting Diodes

Quantitative ultrastructural analysis in cardiac membrane physiology

1978 ◽  
Vol 235 (5) ◽  
pp. C147-C158 ◽  
Author(s):  
E. Page
Keyword(s):  
Quantitative Analysis ◽  
Membrane Structure ◽  
Statistical Approach ◽  
Optical Diffraction ◽  
Intracellular Membrane ◽  
Quantitative Measurements ◽  
Yield Information ◽  
Morphometric Methods ◽  
Sampling Problems ◽  
Membrane Physiology

Quantitative measurements on electron micrographs of heart muscle can yield information useful for cellular physiologists and at present not obtainable in other ways. These methods are subject to preparative artifact, sampling problems, and problems inherent in the mathematical description of ultrastructure. Nevertheless they provide the best available data for membrane areas of the plasmalemma and its components, as well as for membrane areas of the sarcoplasmic reticulum and mitochondria. Morphometric methods can be used to study growth of membranes. Changes in the volumes of intracellular membrane-limited subcompartments can also be measured. Quantitative analysis of freeze-fractured membrane replicas can be carried out either by a statistical approach or by optical diffraction. In this way, physiological perturbations or developmental events leading to changes in membrane permeability can be studied for correlated changes in membrane structure.

Influence of Peripheral on Central Stereopsis: An Induced Depth Tilt Effect

Perception ◽  
1997 ◽  
Vol 26 (1_suppl) ◽  
pp. 276-276
Author(s):  
S Müller ◽  
E R Wist
Keyword(s):  
Opposite Direction ◽  
Rotation Speed ◽  
Neutral Density ◽  
Neutral Density Filter ◽  
Disk Rotation ◽  
Optimal Rotation ◽  
Density Filter ◽  
Pulfrich Effect ◽  
Variable Errors ◽  
Tilted Disk

A large rotating black/white sectored disk (58 deg diameter) viewed with a neutral density filter over one eye is perceived as tilted in depth according to the Pulfrich phenomenon. But with fixation on a centrally located vertical bar (7 deg in length), the disk is perceived as vertical while the central bar is perceived as tilted in the opposite direction. This effect remains even if the central 38 deg portion of the disk is occluded leaving a peripheral annulus 10 deg in width. At an optimal rotation speed of 45° s−1 and a filter of 2 log units, the inter-individual perceived tilt of the bar ranges between 5° and 10° as measured by nulling out the illusory tilt by adjustment with a joystick. Variable errors were extremely small and corresponded well with central stereoscopic resolution. The amount of illusory tilt depends on the speed of disk rotation and filter density, and its direction on the relation between the direction of motion and the filter-covered eye. The effect is not limited to Pulfrich-induced stereotilt: When the disk was stationary but physically tilted in depth, the induced tilt on the central bar corresponded to about 50% of the physical tilt. This effect, in turn, could be cancelled or enhanced by rotating the tilted disk and inducing an appropriate Pulfrich effect. With monocular viewing no induced depth tilt occurs. The results are interpreted in terms of a stereoscopic induced effect operating beyond the known peripheral limits of stereopsis.

Quantitative Analysis of Acquisition of a Conditional Discrimination

1975 ◽  
Vol 37 (1) ◽  
pp. 211-216
Author(s):  
James M. Wagner ◽  
H. Keith Rodewald
Keyword(s):  
Quantitative Analysis ◽  
White Light ◽  
Conditional Discrimination ◽  
Statistical Tests ◽  
Good Congruence

When the center one of three keys was illuminated with one of six stimuli, 40 pecks produced white light on both side keys. Three of the six stimuli set the conditions for reinforcement of a subsequent single peck on the left key, and three occasioned reinforcement for a right-key response. Three pigeons reached a criterion of 18 correct side-key responses in the last 20 presentations of each of the six stimuli. Prior to criterion, responding was stable and near chance levels; immediately thereafter, accuracy rose to 90% correct choices. Results of several statistical tests and good congruence with predictions of Bower's (1961) model suggested acquisition in an all-or-none manner and confirmed Rodewald's (1973) results.

scholarly journals Concentric Mutual Lapping to Improve Sliding Surface Function of SiC Ceramics

2019 ◽  
Vol 13 (6) ◽  
pp. 756-764
Author(s):  
Hiroyuki Kodama ◽  
◽  
Hayato Koyama ◽  
Tomoaki Ishii ◽  
Yusuke Tanimoto ◽  
...  
Keyword(s):  
Quantitative Analysis ◽  
Surface Topography ◽  
Friction Force ◽  
White Light ◽  
Surface Profile ◽  
Sliding Surface ◽  
Sliding Direction ◽  
Sic Ceramics ◽  
Finished Surface ◽  
Effect Of Surface

Ring-shaped SiC ceramics used in sliding components were examined herein. Conventional lapping generates many shallow scratches in random directions in the surface of such SiC ceramics, and these starches extend from the inner circumference of the surface to its perimeter. The scratches affect the ability of the surface to prevent liquid from escaping from the perimeter side to the inner-circumference side of the SiC ring, and they can increase the friction force of the finished surface as a sliding material. We propose concentric mutual lapping to remove the scratches caused by conventional lapping. The surface topography of a SiC ring is evaluated quantitatively using a white light interferometer, and a vector and quantitative analysis of the surface profile is proposed. The results show that concentric mutual lapping can quickly remove the scratches caused by conventional lapping, and subsequently, circumferential scratches are generated along the lapping direction. We have also conducted sliding tests to analyze the effect of surface topography on the surface function as a sliding material. The results reveal that concentric mutual lapping suppresses the differences in surface function that occurred depending on the sliding direction.

Quantitative Measurements of Adsorbed Aminosilanes on Muscovite Mica Using Diffuse Reflectance Infrared Fourier Transform Spectroscopy

1989 ◽  
Vol 43 (7) ◽  
pp. 1240-1248 ◽  
Author(s):  
Lena Vågberg ◽  
Paul De Potocki ◽  
Per Stenius
Keyword(s):  
Fourier Transform ◽  
Quantitative Analysis ◽  
Ir Spectroscopy ◽  
Diffuse Reflectance ◽  
Adsorbed Layer ◽  
Quantitative Measurements ◽  
Muscovite Mica ◽  
Ft Ir ◽  
Diffuse Reflectance Infrared ◽  
Ft Ir Spectroscopy

A method for quantitative analysis of 3-aminopropyltriethoxysilane (γ-APS) and N-(N-vinylbenzyl-2-aminoethyl)-3-aminopropyltrimethoxy-silane hydrochloride (cationic vinylbenzyl silane, CVBS) on muscovite mica powder has been developed with the use of diffuse reflectance FT-IR spectroscopy. The adsorption isotherms determined by this method are reported. The results are compared with a previous study of the adsorption of aminosilanes by ESCA, and possible models of the adsorbed layer are discussed.

scholarly journals Characterization of key aroma compounds in Meilanchun sesame flavor style baijiu by application of aroma extract dilution analysis, quantitative measurements, aroma recombination, and omission/addition experiments

RSC Advances ◽  
2018 ◽  
Vol 8 (42) ◽  
pp. 23757-23767 ◽  
Author(s):  
Jinyuan Sun ◽  
Qinya Li ◽  
Siqi Luo ◽  
Jinglin Zhang ◽  
Mingquan Huang ◽  
...  
Keyword(s):  
Quantitative Analysis ◽  
Active Compound ◽  
Aroma Compounds ◽  
Aroma Extract Dilution Analysis ◽  
Quantitative Measurements ◽  
Aroma Components ◽  
Aroma Recombination

The aroma components in Meilanchun sesame flavor style baijiu were identified by aroma extract dilution analysis (AEDA), quantitative analysis, aroma active compound recombination, and omission/addition experiments.

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