Relationship between Modes of Appearance and Brightness-to-Luminance Ratio for Colored Lights

In a 2004 paper, ‘Hume's Missing Shade of Blue Reconsidered from a Newtonian Perspective,’ Eric Schliesser argues that Hume's well-known discussion of the missing shade of blue ‘reveals considerable ignorance of Newton's achievement in optics,’ and that Hume has failed to assimilate the lessons taught by Newton's optical experiments. I argue in this paper, contrary to Schliesser, that Hume's views on color are logically and evidentially independent of Newton's results. In developing my reading, I will argue that Schliesser accepts an overly broad interpretation of the implications of Newton's experimental results, and takes inadequate account of Hume's disciplined methodological restrictions on the kinds of experiential evidence that are to be admitted in building the foundations of his science of human nature.

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Qualitative flow visualization using colored lights and reflective flakes

Physics of Fluids ◽

10.1063/1.869868 ◽

1999 ◽

Vol 11 (7) ◽

pp. 1702-1704 ◽

Cited By ~ 16

Author(s):

S. T. Thoroddsen ◽

J. M. Bauer

Keyword(s):

Flow Visualization ◽

Colored Lights

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Ability of Rhesus Monkeys to Discriminate Complex Spatial Arrangements of Visual Stimuli

Perceptual and Motor Skills ◽

10.2466/pms.1965.21.2.395 ◽

1965 ◽

Vol 21 (2) ◽

pp. 395-398 ◽

Cited By ~ 1

Author(s):

Hugh Brown ◽

F. W. Remfry ◽

W. C. Bass

Keyword(s):

Rhesus Monkeys ◽

Visual Stimuli ◽

Multidimensional Stimulus ◽

Colored Lights

Two rhesus monkeys were trained in an operant situation to perform for food and water in response to conceptualized stimuli which the animal had to derive from multidimensional stimulus conditions involving random combinations of colored lights.

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A new technique for estimating chromatic isoluminance in humans and monkeys

Visual Neuroscience ◽

10.1017/s0952523800000766 ◽

1990 ◽

Vol 5 (6) ◽

pp. 605-608 ◽

Cited By ~ 6

Author(s):

Avi Chaudhuri ◽

Thomas D. Albright

Keyword(s):

New Technique ◽

Luminance Ratio ◽

Optokinetic Response ◽

Moving Stimulus ◽

Perceptual Judgement ◽

A New Technique ◽

Perceived Motion

AbstractCurrent approaches to the problem of equating different colors for luminance (chromatic isoluminance) rely upon human reports of perceptual events that are reduced at some luminance ratio. In this report, a technique is described that evokes a vivid percept of motion of a textured pattern only at isoluminance. Furthermore, in both humans and monkeys, the moving stimulus produces a striking optokinetic response in the same direction as the perceived motion. If used in this manner, the technique can provide an estimate of chromatic isoluminance in a variety of species and be used to corroborate a human subjects's perceptual judgement.

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Constant-Time Complete Visibility for Robots with Lights: The Asynchronous Case

Algorithms ◽

10.3390/a14020056 ◽

2021 ◽

Vol 14 (2) ◽

pp. 56

Author(s):

Gokarna Sharma ◽

Ramachandran Vaidyanathan ◽

Jerry L. Trahan

Keyword(s):

Mobile Robots ◽

Line Segment ◽

Autonomous Robots ◽

Straight Line Segment ◽

Autonomous Mobile Robots ◽

Asymptotically Optimal ◽

Time Translation ◽

Straight Line ◽

A New Technique ◽

Colored Lights

We consider the distributed setting of N autonomous mobile robots that operate in Look-Compute-Move (LCM) cycles and use colored lights (the robots with lights model). We assume obstructed visibility where a robot cannot see another robot if a third robot is positioned between them on the straight line segment connecting them. In this paper, we consider the problem of positioning N autonomous robots on a plane so that every robot is visible to all others (this is called the Complete Visibility problem). This problem is fundamental, as it provides a basis to solve many other problems under obstructed visibility. In this paper, we provide the first, asymptotically optimal, O(1) time, O(1) color algorithm for Complete Visibility in the asynchronous setting. This significantly improves on an O(N)-time translation of the existing O(1) time, O(1) color semi-synchronous algorithm to the asynchronous setting. The proposed algorithm is collision-free, i.e., robots do not share positions, and their paths do not cross. We also introduce a new technique for moving robots in an asynchronous setting that may be of independent interest, called Beacon-Directed Curve Positioning.

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Automated Training for a “Matching-To-Sample” Task in Aphasia

Journal of Speech and Hearing Research ◽

10.1044/jshr.0801.39 ◽

1965 ◽

Vol 8 (1) ◽

pp. 39-42 ◽

Cited By ~ 13

Author(s):

Allan E. Edwards

Keyword(s):

Visual Discrimination ◽

Matching To Sample ◽

The Subject ◽

Differential Responses ◽

Colored Lights

This study investigated the differential responses of more than 100 aphasics to a “primer” program of automatic training. The subjects were exposed to random shapes on a screen, and responded by pushing buttons to match stimuli. If the response was correct, colored lights were flashed or door chimes sounded. If the response was incorrect, darkness followed. If no errors were made on certain defined trials, the program advanced the subject to jump-ahead tests, or retreated to fall-back tests if errors occurred. Therefore, it seems possible to teach severe aphasics any program which can utilize visual discrimination.

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Changes of mind and absolute evidence

10.31234/osf.io/aj4ht ◽

2019 ◽

Cited By ~ 1

Author(s):

William Turner ◽

Daniel Feuerriegel ◽

Milan Andrejevic ◽

Robert Hester ◽

Stefan Bode

Keyword(s):

Decision Process ◽

Initial Response ◽

Luminance Ratio ◽

Noise Sources ◽

Initial Decision ◽

Luminance Difference ◽

The World ◽

Sensory Evidence

To navigate the world safely, we often need to rapidly ‘change our mind’ about decisions. Current models assume that initial decisions and change-of-mind decisions draw upon common sources of sensory evidence. In two-choice scenarios, this evidence may be ‘relative’ or ‘absolute’. For example, when judging which of two objects is the brightest, the luminance difference and luminance ratio between the two objects are sources of ‘relative’ evidence, which are invariant across additive and multiplicative luminance changes. Conversely, the overall luminance of the two objects combined is a source of ‘absolute’ evidence, which necessarily varies across symmetric luminance manipulations. Previous studies have shown that initial decisions are sensitive to both relative and absolute evidence; however, it is unknown whether change-of-mind decisions are sensitive to absolute evidence. Here, we investigated this question across two experiments. In each experiment participants indicated which of two flickering greyscale squares was brightest. Following an initial decision, the stimuli remained on screen for a brief period and participants could change their response. To investigate the effect of absolute evidence, the overall luminance of the two squares was varied whilst either the luminance difference (Experiment 1) or luminance ratio (Experiment 2) was held constant. In both experiments we found that increases in absolute evidence led to faster, less accurate initial responses and slower changes of mind. Change-of-mind accuracy decreased when the luminance difference was held constant, but remained unchanged when the luminance ratio was fixed. The initial response effects could be explained by the presence of input-dependent noise within the decision process, varying either within or across trials. However, the change-of-mind effects could not be captured by existing models, nor by two modified models which included input-dependent noise sources. This suggests that that the continued integration of sensory evidence following an initial decision operates differently to that described in existing theoretical accounts.

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