Looming in Forensics: Misapplication, Correction and Extension

2021 ◽  
Vol 65 (1) ◽  
pp. 1515-1518
Author(s):  
Frank A. Perez ◽  
Bong J. Walsh
Keyword(s):  
Visual Angle ◽  
Visual Cues ◽  
Open Water ◽  
Threshold Analysis ◽  
Image Size ◽  
Historical Significance ◽  
Angle Change ◽  
Slow Moving ◽  
Nighttime Driving ◽  
Special Case

In recent litigation Human Factors Experts have been misapplying the analysis of the looming threshold for offset motions. Looming (or image size expansion) analysis is appropriate for a rapid direct approach to an object (i.e., rear-end collisions) but is inappropriate for offset motions. Typically, looming threshold analysis is applied to nighttime driving when approaching a slow-moving or stopped vehicle presenting no visual cues other than rear tail lights. This paper lays out the foundation for looming, derives the accepted mathematical equation, and compares it to the rate of visual angle change, which is more applicable to offset motions. An appropriate offset looming threshold equation is derived. In addition, a special case of collision due to looming combined with lateral motion is addressed which has historical significance in open water vessel navigation.

scholarly journals The Strategy of Predator Evasion in Response to a Visual Looming Stimulus in Zebrafish (Danio rerio)

2020 ◽  
Vol 2 (1) ◽  
Author(s):  
A McKee ◽  
M J McHenry
Keyword(s):  
Danio Rerio ◽  
Visual Angle ◽  
Visual Cues ◽  
Adult Zebrafish ◽  
Fish Predator ◽  
Live Fish ◽  
Artificial Stimulus ◽  
Novel Approach ◽  
Escape Speed ◽  
Stimulus Angle

Synopsis A diversity of animals survive encounters with predators by escaping from a looming visual stimulus. Despite the importance of this behavior, it is generally unclear how visual cues facilitate a prey’s survival from predation. Therefore, the aim of this study was to understand how the visual angle subtended on the eye of the prey by the predator affects the distance of adult zebrafish (Danio rerio) from predators. We performed experiments to measure the threshold visual angle and mathematically modeled the kinematics of predator and prey. We analyzed the responses to the artificial stimulus with a novel approach that calculated relationships between hypothetical values for a threshold-stimulus angle and the latency between stimulus and response. These relationships were verified against the kinematic responses of zebrafish to a live fish predator (Herichthys cyanoguttatus). The predictions of our model suggest that the measured threshold visual angle facilitates escape when the predator’s approach is slower than approximately twice the prey’s escape speed. These results demonstrate the capacity and limits to how the visual angle provides a prey with the means to escape a predator.

Visual Perceptions and Observations of an Aphakic Surgeon

1983 ◽  
Vol 57 (3_suppl) ◽  
pp. 1211-1218 ◽  
Author(s):  
Robert M. Anderson
Keyword(s):  
Retinal Detachment ◽  
Light Intensity ◽  
Optic Disc ◽  
Ultraviolet Light ◽  
Visual Angle ◽  
Contact Lenses ◽  
Image Size ◽  
Aphakic Eyes

A surgeon analyzes his perception following removal of cataracts and repair of a retinal detachment. His conclusions are: aphakic eyes perceive ultraviolet light, the optic disc is perceived as a point rather than a space the size of the disc, a certain minimal similarity of light intensity on the two retinas is necessary for fusion of images, reduction telescopes can be made by a combination of contact lenses and trifocals which balance the image size in unilateral aphakia, the visual angle of cataract glasses may be only 56° but is perceived as 90° with a 22° blind sector, a patient can observe the progress of his own cataract by looking through a pinhole, and the optimal prescription for contact lenses in aphakia is with acute vision provided at 75 cm. rather than at 5 or 6 m.

scholarly journals Why colour is complex: Evidence that bees perceive neither brightness nor green contrast in colour signal processing

FACETS ◽  
2018 ◽  
Vol 3 (1) ◽  
pp. 800-817 ◽  
Author(s):  
Leslie Ng ◽  
Jair E. Garcia ◽  
Adrian G. Dyer
Keyword(s):  
Signal Processing ◽  
Apis Mellifera ◽  
Honey Bees ◽  
Visual Angle ◽  
Visual Cues ◽  
Brightness Contrast ◽  
Colour Perception ◽  
Flower Colours ◽  
Colour Signal

Honey bees ( Apis mellifera Linnaeus, 1758) potentially rely on a variety of visual cues when searching for flowers in the environment. Both chromatic and achromatic (brightness) components of flower signals have typically been considered simultaneously to understand how flower colours have evolved. However, it is unclear whether honey bees actually use brightness information in their colour perception. We investigated whether free-flying honey bees can process brightness cues in achromatic stimuli when presented at a large visual angle of 28° to ensure colour processing. We found that green contrast (modulation of the green receptor against the background) and brightness contrast (modulation of all three receptors against the background) did not have a significant effect on the proportion of correct choices made by bees, indicating that they did not appear to use brightness cues in a colour processing context. Our findings also reveal that, even at a small visual angle, honeybees do not reliably process single targets solely based on achromatic information, at least considering values up to 60% modulation of brightness. We discuss these findings in relation to proposed models of bee colour processing. Therefore, caution should be taken when interpreting elemental components of complex flower colours as perceived by different animals.

scholarly journals The upgrading of middle school: CNR Jed and Don streets, Invercargill

1983 ◽  
Vol 16 (1) ◽  
pp. 60-63
Author(s):  
F. N. Buxton
Keyword(s):  
Middle School ◽  
Government Policy ◽  
News Media ◽  
Public Debate ◽  
Earthquake Risk ◽  
District Office ◽  
Media Attention ◽  
Historical Significance ◽  
Structural Concept ◽  
Special Case

Work on this building was done in line with Government policy of replacing or structurally upgrading recognised earthquake risk buildings of unreinforced
brick masonry. The building has little 
of special architectural merit and is
 not of any historical significance, frequent reasons for strengthening
 rather than replacing. In that regard,
 it would be a special case. The decision to strengthen followed considerable public debate, news media attention and controversy lasting some months and investigations carried out on behalf of the various interested bodies. With regard to Middle School, the contract for upgrading was under the overall control of the Southland Education Board Architectural Branch with the Dunedin District Office, Ministry of
 Works and Development, Structural Division being responsible for the structural concept and design of engineering aspects.

scholarly journals Depth Cues Changes Circle Size Judgment Measured by Psychophysical Scaling

2014 ◽  
Vol 7 (1) ◽  
pp. 45-49 ◽  
Author(s):  
Marcelo Fernandes Costa ◽  
Balázs Vince Nagy ◽  
Adsson Magalhães
Keyword(s):  
Visual Angle ◽  
Visual Cues ◽  
Sensory Information ◽  
Apparent Size ◽  
Size Judgment ◽  
Experimental Conditions ◽  
Depth Cues ◽  
Circle Size ◽  
Psychophysical Scaling ◽  
The Right

The aim of our study was to investigate whether different circle sizes, in conditions of pure size judgment and in a simple contextual judgment with an interfering depth suggesting background, produce different size perceptions. We used the magnitude estimation to obtain the apparent size of circles under two different experimental conditions: with a neutral black background and with a convergent gradient to generate an artificial horizon to evoke depth cues. Twenty-two subjects with normal or corrected-to-normal visual acuity (mean age = 21.3 yrs; SD = 1.6) were tested. The procedure consisted of two gray circles at luminance of 40 cd/m2, separated 10 degrees of visual angle apart from each other. On the left side was always present the reference circle (visual angle of 1.1 degree) in which was assigned an arbitrary value of 50 was assigned. The subjects' task was to judge the size of the circles appearing in the right side of the monitor screen assigning a number proportional to the perceived altered size, relative to the reference circle. Seven different sizes (0.6, 0.8, 1.0, 1.1, 1.3, 1.4, 1.5 degrees) were presented in each condition. Our results have shown a high correlation for circle size and depth conditions (R = 0.987 and R = 0.997) between the logs of the stimuli and the subjective magnitude estimated values. The exponents obtained by the Power Law were 0.79 and 1.09, respectively to each condition. Additionally, a gender effect was observed in which males had showed an expansive perception of size with no dependence on the background. We concluded that in the induced depth condition, the perception of the circle sizes were judged subjectively closer to their respective physical size than in the condition of free visual cues. Our data reinforces the integrative manner of perceptual system when working with the sensory information

Extreme self-sacrifice beyond fusion: Moral expansiveness and the special case of allyship

2018 ◽  
Vol 41 ◽  
Author(s):  
Daniel Crimston ◽  
Matthew J. Hornsey
Keyword(s):  
General Theory ◽  
Biological Markers ◽  
Natural Environment ◽  
Relevant Dimension ◽  
Special Case

AbstractAs a general theory of extreme self-sacrifice, Whitehouse's article misses one relevant dimension: people's willingness to fight and die in support of entities not bound by biological markers or ancestral kinship (allyship). We discuss research on moral expansiveness, which highlights individuals’ capacity to self-sacrifice for targets that lie outside traditional in-group markers, including racial out-groups, animals, and the natural environment.

Determination of the phase structure of polymerblends by electron microscopy

1978 ◽  
Vol 36 (1) ◽  
pp. 492-493
Author(s):  
Dr. G. Kaemof
Keyword(s):  
Screw Extruder ◽  
Electron Microscopic ◽  
Thin Sections ◽  
Single Screw Extruder ◽  
Transmission Electron ◽  
The Matrix ◽  
Twin Screw ◽  
Special Case ◽  
Microscopic Investigations

A mixture of polycarbonate (PC) and styrene-acrylonitrile-copolymer (SAN) represents a very good example for the efficiency of electron microscopic investigations concerning the determination of optimum production procedures for high grade product properties.The following parameters have been varied:components of charge (PC : SAN 50 : 50, 60 : 40, 70 : 30), kind of compounding machine (single screw extruder, twin screw extruder, discontinuous kneader), mass-temperature (lowest and highest possible temperature).The transmission electron microscopic investigations (TEM) were carried out on ultra thin sections, the PC-phase of which was selectively etched by triethylamine.The phase transition (matrix to disperse phase) does not occur - as might be expected - at a PC to SAN ratio of 50 : 50, but at a ratio of 65 : 35. Our results show that the matrix is preferably formed by the components with the lower melting viscosity (in this special case SAN), even at concentrations of less than 50 %.

Supporting the Use of Rudimentary Vocalizations

2014 ◽  
Vol 23 (3) ◽  
pp. 132-139 ◽  
Author(s):  
Lauren Zubow ◽  
Richard Hurtig
Keyword(s):  
Rett Syndrome ◽  
Visual Cues ◽  
Acoustic Analysis ◽  
Eye Gaze ◽  
Research Question ◽  
Primary Research ◽  
Multiple Modalities ◽  
Face To Face ◽  
Perceptual Judgments ◽  
The Face

Children with Rett Syndrome (RS) are reported to use multiple modalities to communicate although their intentionality is often questioned (Bartolotta, Zipp, Simpkins, & Glazewski, 2011; Hetzroni & Rubin, 2006; Sigafoos et al., 2000; Sigafoos, Woodyatt, Tuckeer, Roberts-Pennell, & Pittendreigh, 2000). This paper will present results of a study analyzing the unconventional vocalizations of a child with RS. The primary research question addresses the ability of familiar and unfamiliar listeners to interpret unconventional vocalizations as “yes” or “no” responses. This paper will also address the acoustic analysis and perceptual judgments of these vocalizations. Pre-recorded isolated vocalizations of “yes” and “no” were presented to 5 listeners (mother, father, 1 unfamiliar, and 2 familiar clinicians) and the listeners were asked to rate the vocalizations as either “yes” or “no.” The ratings were compared to the original identification made by the child's mother during the face-to-face interaction from which the samples were drawn. Findings of this study suggest, in this case, the child's vocalizations were intentional and could be interpreted by familiar and unfamiliar listeners as either “yes” or “no” without contextual or visual cues. The results suggest that communication partners should be trained to attend to eye-gaze and vocalizations to ensure the child's intended choice is accurately understood.

Visual Cues, Decoding, Literacy, and the Brain

2007 ◽  
Vol 17 (2) ◽  
pp. 9-12
Author(s):  
Judith A Curtin
Keyword(s):  
Visual Cues ◽  
The Brain

Test Validation Without Measurement

2016 ◽  
Vol 32 (3) ◽  
pp. 204-214 ◽  
Author(s):  
Emilie Lacot ◽  
Mohammad H. Afzali ◽  
Stéphane Vautier
Keyword(s):  
Test Data ◽  
Test Scores ◽  
Scientific Explanation ◽  
Test Validation ◽  
Clinical Tests ◽  
Ethical Perspective ◽  
Power Of Test ◽  
Memory Accuracy ◽  
Social Uses ◽  
Special Case

Abstract. Test validation based on usual statistical analyses is paradoxical, as, from a falsificationist perspective, they do not test that test data are ordinal measurements, and, from the ethical perspective, they do not justify the use of test scores. This paper (i) proposes some basic definitions, where measurement is a special case of scientific explanation; starting from the examples of memory accuracy and suicidality as scored by two widely used clinical tests/questionnaires. Moreover, it shows (ii) how to elicit the logic of the observable test events underlying the test scores, and (iii) how the measurability of the target theoretical quantities – memory accuracy and suicidality – can and should be tested at the respondent scale as opposed to the scale of aggregates of respondents. (iv) Criterion-related validity is revisited to stress that invoking the explanative power of test data should draw attention on counterexamples instead of statistical summarization. (v) Finally, it is argued that the justification of the use of test scores in specific settings should be part of the test validation task, because, as tests specialists, psychologists are responsible for proposing their tests for social uses.

Sign in / Sign up

Export Citation Format

Share Document