The Experts below are selected from a list of 67653 Experts worldwide ranked by ideXlab platform
Martin S Banks - One of the best experts on this subject based on the ideXlab platform.
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blur and disparity are complementary cues to depth
Current Biology, 2012Co-Authors: Robert T Held, Emily A Cooper, Martin S BanksAbstract:Estimating depth from binocular disparity is extremely precise, and the cue does not depend on statistical regularities in the environment. Thus, disparity is commonly regarded as the best visual cue for determining 3D layout. But depth from disparity is only precise near where one is looking; it is quite imprecise elsewhere. Away from fixation, vision resorts to using other depth cues-e.g., Linear Perspective, familiar size, aerial Perspective. But those cues depend on statistical regularities in the environment and are therefore not always reliable. Depth from defocus blur relies on fewer assumptions and has the same geometric constraints as disparity but different physiological constraints. Blur could in principle fill in the parts of visual space where disparity is imprecise. We tested this possibility with a depth-discrimination experiment. Disparity was more precise near fixation and blur was indeed more precise away from fixation. When both cues were available, observers relied on the more informative one. Blur appears to play an important, previously unrecognized role in depth perception. Our findings lead to a new hypothesis about the evolution of slit-shaped pupils and have implications for the design and implementation of stereo 3D displays.
Sneha Suresh - One of the best experts on this subject based on the ideXlab platform.
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Ensemble size judgments account for size constancy
Attention Perception & Psychophysics, 2020Co-Authors: Jason Haberman, Sneha SureshAbstract:The natural environment is full of redundant information that the visual system compresses into an ensemble representation by averaging features of groups of items. Ensemble perception has been shown to operate with remarkable flexibility, efficiently integrating information across a variety of visual domains. In the current set of experiments, we tested whether average size representations reflect the physical size of objects displayed on a screen or perceptual transformations due to size constancy. We induced a perceptual change by presenting sets of triangles with Linear Perspective cues – lines converging at the horizon. Assuming a constant size, these cues cause individual objects “in the distance” to appear larger than objects without distance cues, due to size constancy heuristics. Observers viewed sets of triangles with and without Linear Perspective cues and judged whether a subsequently presented test triangle was larger or smaller than the average size of the preceding set. Results revealed ensemble size representations took size constancy into account, reflecting the perceived size of the triangles rather than their absolute size. Interestingly, the amount of bias exhibited was well characterized by the summed bias associated with each of the three triangles presented individually. Other pictorial cues to depth, such as occlusion and height-in-field, did not elicit the same bias when those were the only depth cues available. Overall, our results complement and extend other work showing that average size reflects the perceptual size of individual items in a set.
Quan Lei - One of the best experts on this subject based on the ideXlab platform.
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illusory distance modulates perceived size of afterimage despite the disappearance of depth cues
PLOS ONE, 2016Co-Authors: Jiehui Qian, Shengxi Liu, Quan LeiAbstract:It is known that the perceived size of an afterimage is modulated by the perceived distance between the observer and the depth plane on which the afterimage is projected (Emmert’s law). Illusions like Ponzo demonstrate that illusory distance induced by depth cues can also affect the perceived size of an object. In this study, we report that the illusory distance not only modulates the perceived size of object’s afterimage during the presence of the depth cues, but the modulation persists after the disappearance of the depth cues. We used an adapted version of the classic Ponzo illusion. Illusory depth perception was induced by Linear Perspective cues with two tilted lines converging at the upper boundary of the display. Two horizontal bars were placed between the two lines, resulting in a percept of the upper bar to be farther away than the lower bar. Observers were instructed to make judgment about the relative size of the afterimage of the lower and the upper bars after adaptation. When the Perspective cues and the bars were static, the illusory effect of the Ponzo afterimage is consistent with that of the traditional size-distance illusion. When the Perspective cues were flickering and the bars were static, only the afterimage of the latter was perceived, yet still a considerable amount of the illusory effect was perceived. The results could not be explained by memory of a prejudgment of the bar length during the adaptation phase. The findings suggest that cooccurrences of depth cues and object may link a depth marker for the object, so that the perceived size of the object or its afterimage is modulated by feedback of depth information from higher-level visual cortex even when there is no depth cues directly available on the retinal level.
Grahn Sten - One of the best experts on this subject based on the ideXlab platform.
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Value Chains vs. Ecosystems : Current Perspectives Among Swedish SMEs Entering the Interconnected World of IoT
'IOS Press', 2020Co-Authors: Centerholt Victor, Kjidderö Frida, Saarikko Ted, Grahn StenAbstract:Smart connected industrial products and the Internet of Things (IoT) are transforming the industrial business landscape in a radical way. To reach the full potential of IoT-technologies manufacturing firms are forced to rethink almost every aspect of their value creation process. To utilize this promising digital technology and to cope with the new market conditions of IoT environments, research shows that industrial firms have to make a fundamental shift in value creation logic and break free from the value chain Perspective of business. Instead they have to embrace a view where value is co-created within ecosystems in both a vertical and a horizontal manner. By exploring the value creation logic of small and medium sized (SME) Swedish industrial machinery manufacturers, this study contributes to a deeper understanding of how manufacturing firms view their value creation processes and how aligned this logic is to the latest research in IoT. The study found that Swedish industrial machine manufacturers do understand the transformative force of IoT-technologies and see great business opportunities to utilize IoT in their business. The study, however, identified a lack of co-creation and difficulties in embracing an ecosystem Perspective. While quick to embrace change on a technical level, respondents still adhere to a firm-centric and Linear Perspective of value creation, with a strong attachment to the value chain concept. The study suggests that it is not a lack of technical proficiency or engineering know-how, but rather an adherence to goods-dominant logic and attachment to the value chain concept that prevent Swedish SME manufacturers from fully embracing the growing market of industrial IoT. Hence, we see an urgent need for both practitioners and academia to shift their attention from the dazzling potential of cutting-edge technologies to the nitty-gritty business of incorporating co-creation and ecosystem-thinking into current business practices
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Value Chains vs. Ecosystems : Current Perspectives Among Swedish SMEs Entering the Interconnected World of IoT
'IOS Press', 2020Co-Authors: Centerholt Victor, Kjidderö Frida, Saarikko Ted, Grahn StenAbstract:Smart connected industrial products and the Internet of Things (IoT) are transforming the industrial business landscape in a radical way. To reach the full potential of IoT-technologies manufacturing firms are forced to rethink almost every aspect of their value creation process. To utilize this promising digital technology and to cope with the new market conditions of IoT environments, research shows that industrial firms have to make a fundamental shift in value creation logic and break free from the value chain Perspective of business. Instead they have to embrace a view where value is co-created within ecosystems in both a vertical and a horizontal manner. By exploring the value creation logic of small and medium sized (SME) Swedish industrial machinery manufacturers, this study contributes to a deeper understanding of how manufacturing firms view their value creation processes and how aligned this logic is to the latest research in IoT. The study found that Swedish industrial machine manufacturers do understand the transformative force of IoT-technologies and see great business opportunities to utilize IoT in their business. The study, however, identified a lack of co-creation and difficulties in embracing an ecosystem Perspective. While quick to embrace change on a technical level, respondents still adhere to a firm-centric and Linear Perspective of value creation, with a strong attachment to the value chain concept. The study suggests that it is not a lack of technical proficiency or engineering know-how, but rather an adherence to goods-dominant logic and attachment to the value chain concept that prevent Swedish SME manufacturers from fully embracing the growing market of industrial IoT. Hence, we see an urgent need for both practitioners and academia to shift their attention from the dazzling potential of cutting-edge technologies to the nitty-
Jason Haberman - One of the best experts on this subject based on the ideXlab platform.
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Ensemble size judgments account for size constancy
Attention Perception & Psychophysics, 2020Co-Authors: Jason Haberman, Sneha SureshAbstract:The natural environment is full of redundant information that the visual system compresses into an ensemble representation by averaging features of groups of items. Ensemble perception has been shown to operate with remarkable flexibility, efficiently integrating information across a variety of visual domains. In the current set of experiments, we tested whether average size representations reflect the physical size of objects displayed on a screen or perceptual transformations due to size constancy. We induced a perceptual change by presenting sets of triangles with Linear Perspective cues – lines converging at the horizon. Assuming a constant size, these cues cause individual objects “in the distance” to appear larger than objects without distance cues, due to size constancy heuristics. Observers viewed sets of triangles with and without Linear Perspective cues and judged whether a subsequently presented test triangle was larger or smaller than the average size of the preceding set. Results revealed ensemble size representations took size constancy into account, reflecting the perceived size of the triangles rather than their absolute size. Interestingly, the amount of bias exhibited was well characterized by the summed bias associated with each of the three triangles presented individually. Other pictorial cues to depth, such as occlusion and height-in-field, did not elicit the same bias when those were the only depth cues available. Overall, our results complement and extend other work showing that average size reflects the perceptual size of individual items in a set.