Recent Advancements towards Sustainability in Rotomoulding.

Rotational moulding is a unique low-shear process used to manufacture hollow parts. The process is an excellent process method for batch processing, minimal waste and stress-free parts. However, the process has drawbacks such as long cycle times, gas dependency and a limited palette of materials relative to other process methods.

Mechanical Performance of Rotationally Molded Multilayer mLDPE/Banana-Fiber Composites.

The incorporation of materials different from the polymer within the rotational molding process usually results in lowered mechanical properties, where impact strength is of particular concern. In order to overcome this issue, multilayer structures of virgin polyethylene (PE) and banana fiber composites were prepared to determine the impact of the different layers on the performance of the final part. Cycle time has been studied to identify the influence of the addition of fibers in the process.

Isolation of brightness induction effects on target patches from adjacent surrounds and remote backgrounds.

The brightness (perceived intensity) of a region of visual space depends on its luminance and on the luminance of nearby regions. This phenomenon is called brightness induction and includes both brightness contrast and assimilation. Historically, and on a purely descriptive level, brightness contrast refers to a directional shift in target brightness away from the brightness of an adjacent region while assimilation refers to a brightness shift toward that of an adjacent region.

Recent Developments in Inorganic Composites in Rotational Molding.

Rotational molding allows for obtaining hollow parts with good aesthetics and properties, having as main drawbacks the lack of pressure and the long cycle times, which limit the range of materials. Different fillers have been introduced in rotomolding to obtain composite materials assessed. This review has shown that glass fibers or particles are the most common material among them, although carbon fibers or clays have also been studied.

Content-Adaptive Memory for Viewer-Aware Energy-Quality Scalable Mobile Video Systems.

Mobile devices are becoming ever more popular for streaming videos, which account for the majority of all data traffic on the internet. Memory is a critical component in mobile video processing systems, increasingly dominating power consumption. Today, memory designers are still focusing on hardware-level power optimization techniques, which usually come with significant implementation cost (e.

Recycling of polymeric fraction of cable waste by rotational moulding.

This study focuses on the mechanical recycling of polymeric waste that is produced in considerable amount from the cable industry. Every year large amounts of cables become waste; wires recycling has traditionally focused on metal recovery, while the polymer cover has just been considered as a residue, being landfilled or incinerated. Nowadays, increasingly restrictive regulations and concern about environment make necessary to reduce landfilling as much as possible.

Auditory capture of visual motion: effects on perception and discrimination.

We asked whether the perceived direction of visual motion and contrast thresholds for motion discrimination are influenced by the concurrent motion of an auditory sound source. Visual motion stimuli were counterphasing Gabor patches, whose net motion energy was manipulated by adjusting the contrast of the leftward-moving and rightward-moving components. The presentation of these visual stimuli was paired with the simultaneous presentation of auditory stimuli, whose apparent motion in 3D auditory space (rightward, leftward, static, no sound) was manipulated using interaural time and intensity differences, and Doppler cues.

Dissecting the influence of the collinear and flanking bars in White's effect.

In White's effect equiluminant test patches placed on the black and white bars of a square-wave grating appear different in brightness. The illusion has generated intense interest because the direction of the brightness effect does not correlate with the amount of black or white border in contact with the test patch, or in its general vicinity. Therefore, unlike brightness induction effects such as simultaneous contrast, White's effect is not consistent with explanations based on contrast or assimilation that depend solely on the relative amounts of black and white surrounding the test patches.

Comments and responses to "Theoretical approaches to lightness and perception".

In his review of the literature Kingdom (2011) noted that “Divided into different camps, each with its own preferred stimuli, methodology and theory, the study of LBT (lightness, brightness, transparency) is sometimes more reminiscent of the social sciences with its deep ideological divides than it is of the neurosciences”. Methodology and theory clearly separate our work from that of Gilchrist as described by Kingdom (2011). The similarity of the underlying problems, however, has led us to investigate the roots of these differences and to propose a framework to bridge the divide and advance the field (Blakeslee & McCourt, 2015).

Dissociation of perception and action in audiovisual multisensory integration.

The 'temporal rule' of multisensory integration (MI) proposes that unisensory stimuli, and the neuronal responses they evoke, must fall within a window of integration. Ecological validity demands that MI should occur only for physically simultaneous events (which may give rise to non-simultaneous neural activations), and spurious neural response simultaneities unrelated to environmental multisensory occurrences must somehow be rejected. Two experiments investigated the requirements of simultaneity for facilitative MI.

What visual illusions tell us about underlying neural mechanisms and observer strategies for tackling the inverse problem of achromatic perception.

Research in lightness perception centers on understanding the prior assumptions and processing strategies the visual system uses to parse the retinal intensity distribution (the proximal stimulus) into the surface reflectance and illumination components of the scene (the distal stimulus-ground truth). It is agreed that the visual system must compare different regions of the visual image to solve this inverse problem; however, the nature of the comparisons and the mechanisms underlying them are topics of intense debate. Perceptual illusions are of value because they reveal important information about these visual processing mechanisms.

The Oriented Difference of Gaussians (ODOG) model of brightness perception: Overview and executable Mathematica notebooks.

The Oriented Difference of Gaussians (ODOG) model of brightness (perceived intensity) by Blakeslee and McCourt (Vision Research 39:4361-4377, 1999), which is based on linear spatial filtering by oriented receptive fields followed by contrast normalization, has proven highly successful in parsimoniously predicting the perceived intensity (brightness) of regions in complex visual stimuli such as White's effect, which had been believed to defy filter-based explanations. Unlike competing explanations such as anchoring theory, filling-in, edge-integration, or layer decomposition, the spatial filtering approach embodied by the ODOG model readily accounts for the often overlooked but ubiquitous gradient structure of induction which, while most striking in grating induction, also occurs within the test fields of classical simultaneous brightness contrast and the White stimulus. Also, because the ODOG model does not require defined regions of interest, it is generalizable to any stimulus, including natural images.

Brightness induction and suprathreshold vision: effects of age and visual field.

A variety of visual capacities show significant age-related alterations. We assessed suprathreshold contrast and brightness perception across the lifespan in a large sample of healthy participants (N=155; 142) ranging in age from 16 to 80 years. Experiment 1 used a quadrature-phase motion cancelation technique (Blakeslee & McCourt, 2008) to measure canceling contrast (in central vision) for induced gratings at two temporal frequencies (1 Hz and 4 Hz) at two test field heights (0.

Modeling lateral geniculate nucleus response with contrast gain control. Part 2: analysis.

Cope et al. [J. Opt.

Lighting direction and visual field modulate perceived intensity of illumination.

When interpreting object shape from shading the visual system exhibits a strong bias that illumination comes from above and slightly from the left. We asked whether such biases in the perceived direction of illumination might also influence its perceived intensity. Arrays of nine cubes were stereoscopically rendered where individual cubes varied in their 3D pose, but possessed identical triplets of visible faces.

The roles of physical and physiological simultaneity in audiovisual multisensory facilitation.

A series of experiments measured the audiovisual stimulus onset asynchrony (SOAAV), yielding facilitative multisensory integration. We evaluated (1) the range of SOAAV over which facilitation occurred when unisensory stimuli were weak; (2) whether the range of SOAAV producing facilitation supported the hypothesis that physiological simultaneity of unisensory activity governs multisensory facilitation; and (3) whether AV multisensory facilitation depended on relative stimulus intensity. We compared response-time distributions to unisensory auditory (A) and visual (V) stimuli with those to AV stimuli over a wide range (300 and 20 ms increments) of SOAAV, across four conditions of varying stimulus intensity.

Modeling lateral geniculate nucleus response with contrast gain control. Part 1: formulation.

A class of models for lateral geniculate nucleus (LGN) on-cell behavior is proposed. The models consist of a linear filter with divisive normalization by root mean square local contrast and include an intrinsic noise density parameter. The properties of these models are shown to match observed LGN behavior: (1) a linear response to low-magnitude stimuli; (2) a linear response without saturation (luxotonic behavior) for zero-contrast stimuli (homogeneous fields) with increasing magnitude; and (3) response saturation for nonzero contrast stimuli with increasing magnitude.

Analysis of multidimensional difference-of-Gaussians filters in terms of directly observable parameters.

The difference-of-Gaussians (DOG) filter is a widely used model for the receptive field of neurons in the retina and lateral geniculate nucleus (LGN) and is a potential model in general for responses modulated by an excitatory center with an inhibitory surrounding region. A DOG filter is defined by three standard parameters: the center and surround sigmas (which define the variance of the radially symmetric Gaussians) and the balance (which defines the linear combination of the two Gaussians). These parameters are not directly observable and are typically determined by nonlinear parameter estimation methods applied to the frequency response function.

Brightness induction magnitude declines with increasing distance from the inducing field edge.

Brightness induction refers to a class of visual illusions where the perceived intensity of a region of space is influenced by the luminance of surrounding regions. These illusions are significant because they provide insight into the neural organization and processing strategies employed by the visual system. The nature of these processing strategies, however, has long been debated.

Atypical category processing and hemispheric asymmetries in high-functioning children with autism: revealed through high-density EEG mapping.

Behavioral evidence for an impaired ability to group objects based on similar physical or semantic properties in autism spectrum disorders (ASD) has been mixed. Here, we recorded brain activity from high-functioning children with ASD as they completed a visual-target detection task. We then assessed the extent to which object-based selective attention automatically generalized from targets to non-target exemplars from the same well-known object class (e.

When is spatial filtering enough? Investigation of brightness and lightness perception in stimuli containing a visible illumination component.

Brightness (perceived intensity) and lightness (perceived reflectance) matching were investigated in seven well-known visual stimuli that contain a visible shadow or transparent overlay. These stimuli are frequently upheld as evidence that low-level spatial filtering is inadequate to explain brightness/lightness illusions and that additional mid- or high-level mechanisms are required. The argument in favor of rejecting low-level spatial filtering explanations has been founded on the erroneous assumption that equating test patch and near surround luminance is sufficient to control for and rule out this type of mechanism.

Spatiotemporal analysis of brightness induction.

Brightness induction refers to a class of visual illusions in which the perceived intensity of a region of space is influenced by the luminance of surrounding regions. These illusions are significant because they provide insight into the neural organization of the visual system. A novel quadrature-phase motion cancelation technique was developed to measure the magnitude of the grating induction brightness illusion across a wide range of spatial frequencies, temporal frequencies and test field heights.

Hemifield asymmetry in the potency of exogenous auditory and visual cues.

Neurologically normal subjects misperceive the midpoints of lines (PSE) as reliably leftward of veridical center, a phenomenon known as pseudoneglect. This leftward bias reflects the dominance of the right cerebral hemisphere in deploying spatial attention. Transient visual cues, delivered to either the left or right endpoints of lines, modulate PSE such that leftward biases are increased by leftward cues, and are decreased by rightward cues, relative to a no-cue control condition.