570 research outputs found

    Integration biases in the Ouchi and other visual illusions

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    A texture pattern devised by the Japanese artist H Ouchi has attracted wide attention because of the striking appearance of relative motion it evokes. The illusion has been the subject of several recent empirical studies. A new account is presented, along with a simple experimental test, that attributes the illusion to a bias in the way that local motion signals generated at different locations on each element are combined to code element motion. The account is generalised to two spatial illusions, the Judd illusion and the Zöllner illusion (previously considered unrelated to the Ouchi illusion). The notion of integration bias is consistent with recent Bayesian approaches to visual coding, according to which the weight attached to each signal reflects its reliability and likelihood

    Aesthetic judgement of orientation in modern art

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    When creating an artwork, the artist makes a decision regarding the orientation at which the work is to be hung based on their aesthetic judgement and the message conveyed by the piece. Is the impact or aesthetic appeal of a work diminished when it is hung at an incorrect orientation? To investigate this question, Experiment 1 asked whether naïve observers can appreciate the correct orientation (as defined by the artist) of 40 modern artworks, some of which are entirely abstract. Eighteen participants were shown 40 paintings in a series of trials. Each trial presented all four cardinal orientations on a computer screen, and the participant was asked to select the orientation that was most attractive or meaningful. Results showed that the correct orientation was selected in 48% of trials on average, significantly above the 25% chance level, but well below perfect performance. A second experiment investigated the extent to which the 40 paintings contained recognisable content, which may have mediated orientation judgements. Recognition rates varied from 0% for seven of the paintings to 100% for five paintings. Orientation judgements in Experiment 1 correlated significantly with “meaningful” content judgements in Experiment 2: 42% of the variance in orientation judgements in Experiment 1 was shared with recognition of meaningful content in Experiment 2. For the seven paintings in which no meaningful content at all was detected, 41% of the variance in orientation judgements was shared with variance in a physical measure of image content, Fourier amplitude spectrum slope. For some paintings, orientation judgements were quite consistent, despite a lack of meaningful content. The origin of these orientation judgements remains to be identified

    A step to VAR: the vision science of offside calls by Video Assistant Referees

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    The Video Assistant Referee (VAR) system has had a major impact on decision-making in professional association football. However, offside decisions remain a major area of dispute and debate, with over 34 goals ruled out in the first season of VAR in the Premier League. Evidence in vision science points toward two problems with the application of the offside law in VAR, due to their use of a live TV video feed in reviews. First, due to physical and perceptual limits on spatial resolution, there is a significant probability that the spatial positions of the ball and players as judged by VAR will be several centimetres to one side of their true positions. Second, the 50Hz TV update rate means that judgements of the time-of-contact between player and ball will on average be 10ms too late, which translates into an increased likelihood of offside calls in fast-moving play. Suggestions are made for how to compensate for these problems during decision-making

    The Sex Factor in Blake\u27s Cosmology

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    This paper makes no pretense of being all-embracing. Rather it follows a subsidiary factor in Blake\u27s thought from its obscure origin to its unique fulfillment. It attempts to uncover in Blake\u27s personal life the causes of his attitude toward sex, to visualize the effect this attitude had on his thought, and to point out the important place that sex occupies in Blake\u27s completed cosmology

    Turbine blade illusion

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    In January 2017, a large wind turbine blade was installed temporarily in a city square as a public artwork. At first sight, media photographs of the installation appeared to be fakes – the blade looks like it could not really be part of the scene. Close inspection of the object shows that its paradoxical visual appearance can be attributed to unconscious assumptions about object shape and light source direction

    Is the perception of intent by association football officials influenced by video playback speed?

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    Recent research on motion perception indicates that when we view actions in slow-motion, the perceived degree of intent behind those actions can increase. Slow-motion replays are widely used in the checking and review of refereeing decisions by video assistant referees (VAR) in association football. To test whether the decisions of referees are subject to such a bias, 80 elite English professional football officials made decisions about 60 incidents recorded in professional European leagues (recorded as fouls, yellow-card offences or red-card offences by the on-field referee). Both real-time (1×) and slow-motion (0.25×) playback speeds were used. Participants had no prior knowledge of the incidents, playback speeds or disciplinary sanctions relating to each clip. Three judgements were made about each incident: extent of contact, degree of intent, and disciplinary sanction. Results showed an effect of playback speed on decision-making, but not a consistent bias due to slow-motion. Instead the distinction between yellow-card and red-card offences was clearer: Under slow-motion, yellow-card incidents were judged as less severe, and red-card incidents are judged as more severe, thus enhancing the distinction between these offences. These results are inconsistent with previous scientific reports that perceived intent is heightened by slow video playback speed

    Interactions between motion and form processing in the human visual system

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    The predominant view of motion and form processing in the human visual system assumes that these two attributes are handled by separate and independent modules. Motion processing involves filtering by direction-selective sensors, followed by integration to solve the aperture problem. Form processing involves filtering by orientation-selective and size-selective receptive fields, followed by integration to encode object shape. It has long been known that motion signals can influence form processing in the well-known Gestalt principle of common fate; texture elements which share a common motion property are grouped into a single contour or texture region. However, recent research in psychophysics and neuroscience indicates that the influence of form signals on motion processing is more extensive than previously thought. First, the salience and apparent direction of moving lines depends on how the local orientation and direction of motion combine to match the receptive field properties of motion-selective neurons. Second, orientation signals generated by “motion-streaks” influence motion processing; motion sensitivity, apparent direction and adaptation are affected by simultaneously present orientation signals. Third, form signals generated by human body shape influence biological motion processing, as revealed by studies using point-light motion stimuli. Thus, form-motion integration seems to occur at several different levels of cortical processing, from V1 to STS

    Thermistor thermometry in investigational work

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    Project Number 22-1301-0002 Research ReportAF Contract Number 18(600)-41

    Letter from George Sibley & Thomas Mather to the [Secretary of War], January 20, 1827

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    Transcript of Letter from George Sibley & Thomas Mather to the [Secretary of War], January 20, 1827. Commissioners discuss finishing up the survey; Sibley will go back and make any corrections to the road, if necessary
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