Calcium phosphate stabilization of fly ash with chloride extraction.

Science.gov (United States)

Nzihou, Ange; Sharrock, Patrick

2002-01-01

Municipal solid waste incinerator by products include fly ash and air pollution control residues. In order to transform these incinerator wastes into reusable mineral species, soluble alkali chlorides must be separated and toxic trace elements must be stabilized in insoluble form. We show that alkali chlorides can be extracted efficiently in an aqueous extraction step combining a calcium phosphate gel precipitation. In such a process, sodium and potassium chlorides are obtained free from calcium salts, and the trace metal ions are immobilized in the calcium phosphate matrix. Moderate calcination of the chemically treated fly ash leads to the formation of cristalline hydroxylapatite. Fly ash spiked with copper ions and treated by this process shows improved stability of metal ions. Leaching tests with water or EDTA reveal a significant drop in metal ion dissolution. Hydroxylapatite may trap toxic metals and also prevent their evaporation during thermal treatments. Incinerator fly ash together with air pollution control residues, treated by the combined chloride extraction and hydroxylapatite formation process may be considered safe to use as a mineral filler in value added products such as road base or cement blocks.

Stabilization of chromium-bearing electroplating sludge with MSWI fly ash-based Friedel matrices.

Science.gov (United States)

Qian, Guangren; Yang, Xiaoyan; Dong, Shixiang; Zhou, Jizhi; Sun, Ying; Xu, Yunfeng; Liu, Qiang

2009-06-15

This work investigated the feasibility and effectiveness of MSWI fly ash-based Friedel matrices on stabilizing/solidifying industrial chromium-bearing electroplating sludge using MSWI fly ash as the main raw material with a small addition of active aluminum. The compressive strength, leaching behavior and chemical speciation of heavy metals and hydration phases of matrices were characterized by TCLP, XRD, FTIR and other experimental methods. The results revealed that MSWI fly ash-based Friedel matrices could effectively stabilize chromium-bearing electroplating sludge, the formed ettringite and Friedel phases played a significant role in the fixation of heavy metals in electroplating sludge. The co-disposal of chromium-bearing electroplating sludge and MSWI fly ash-based Friedel matrices with a small addition of active aluminum is promising to be an effective way of stabilizing chromium-bearing electroplating sludge.

Gaze shifts and fixations dominate gaze behavior of walking cats

Science.gov (United States)

Rivers, Trevor J.; Sirota, Mikhail G.; Guttentag, Andrew I.; Ogorodnikov, Dmitri A.; Shah, Neet A.; Beloozerova, Irina N.

2014-01-01

Vision is important for locomotion in complex environments. How it is used to guide stepping is not well understood. We used an eye search coil technique combined with an active marker-based head recording system to characterize the gaze patterns of cats walking over terrains of different complexity: (1) on a flat surface in the dark when no visual information was available, (2) on the flat surface in light when visual information was available but not required, (3) along the highly structured but regular and familiar surface of a horizontal ladder, a task for which visual guidance of stepping was required, and (4) along a pathway cluttered with many small stones, an irregularly structured surface that was new each day. Three cats walked in a 2.5 m corridor, and 958 passages were analyzed. Gaze activity during the time when the gaze was directed at the walking surface was subdivided into four behaviors based on speed of gaze movement along the surface: gaze shift (fast movement), gaze fixation (no movement), constant gaze (movement at the body’s speed), and slow gaze (the remainder). We found that gaze shifts and fixations dominated the cats’ gaze behavior during all locomotor tasks, jointly occupying 62–84% of the time when the gaze was directed at the surface. As visual complexity of the surface and demand on visual guidance of stepping increased, cats spent more time looking at the surface, looked closer to them, and switched between gaze behaviors more often. During both visually guided locomotor tasks, gaze behaviors predominantly followed a repeated cycle of forward gaze shift followed by fixation. We call this behavior “gaze stepping”. Each gaze shift took gaze to a site approximately 75–80 cm in front of the cat, which the cat reached in 0.7–1.2 s and 1.1–1.6 strides. Constant gaze occupied only 5–21% of the time cats spent looking at the walking surface. PMID:24973656

Comparative leaching of six toxic metals from raw and chemically stabilized MSWI fly ash using citric acid.

Science.gov (United States)

Wang, Huawei; Fan, Xinxiu; Wang, Ya-Nan; Li, Weihua; Sun, Yingjie; Zhan, Meili; Wu, Guizhi

2018-02-15

The leaching behavior of six typical toxic metals (Pb, Zn, Cr, Cd, Cu and Ni) from raw and chemically stabilized (phosphate and chelating agent) municipal solid waste incineration (MSWI) fly ash were investigated using citric acid. Leaching tests indicated that phosphate stabilization can effectively decrease the leaching of Zn, Cd and Cr; whereas chelating agent stabilization shows a strong ability to lower the release of Pb, Cd and Cu, but instead increases the solubility of Zn and Cr at low pH conditions. Sequential extraction results suggested that the leaching of Pb, Zn and Cd in both the stabilized MSWI fly ash samples led to the decrease in Fe/Mn oxide fraction and the increase in exchangeable and carbonate fractions. The leaching of Cr was due to the decrease in exchangeable, carbonate and Fe/Mn oxide fractions in phosphate-stabilized and chelating agent-stabilized MSWI fly ash. The leaching of Cu in both stabilized MSWI fly ash was greatly ascribed to the decrease in Fe/Mn oxide and oxidisable fractions. Moreover, predicted curves by geochemical model indicated that both stabilized MSWI fly ash have the risk of releasing toxic metals under strong acid environment. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effect of Alkaline Activator to Fly Ash Ratio for Geopolymer Stabilized Soil

Directory of Open Access Journals (Sweden)

Abdullah Muhammad Sofian

2017-01-01

Full Text Available Geopolymer technology have been developed and explored especially in the construction material field. However, lack of research related to geopolymer stabilized soil. In this research, the utilization of geopolymer has been investigated to stabilize the soil including the factors that affecting the geopolymerization process. Unconfined compressive test (UCT used as indicator to the strength development and hence evaluating the performance of geopolymer stabilized soil. This paper focusing on the effect of fly ash/alkaline activator ratio, Na2SiO3/NaOH ratio and curing time on geopolymer stabilized soil. A various mix design at different fly ash/alkaline activator ratio, Na2SiO3/NaOH ratio were prepared and cured for 7 and 28 days. Molarity and the percentage of geopolymer to soil were fixed at 10 molar and 8 percent respectively. Then, the UCT tests were carried out on 38mm diameter x 76mm height specimens. The highest strength obtained at the fly ash/alkaline activator ratio 2.5 and Na2SiO3/NaOH ratio 2.0 at 28 days curing time.

Assessing fly ash treatment: remediation and stabilization of heavy metals.

Science.gov (United States)

Lima, A T; Ottosen, Lisbeth M; Ribeiro, Alexandra B

2012-03-01

Fly ashes from Municipal Solid Waste (MSW), straw (ST) and co-combustion of wood (CW) are here analyzed with the intent of reusing them. Two techniques are assessed, a remediation technique and a solidification/stabilization one. The removal of heavy metals from fly ashes through the electrodialytic process (EDR) has been tried out before. The goal of removing heavy metals has always been the reuse of fly ash, for instance in agricultural fields (BEK). The best removal rates are here summarized and some new results have been added. MSW fly ashes are still too hazardous after treatment to even consider application to the soil. ST ash is the only residue that gets concentrations low enough to be reused, but its fertilizing value might be questioned. An alternative reuse for the three ashes is here preliminary tested, the combination of fly ash with mortar. Fly ashes have been substituted by cement fraction or aggregate fraction. Surprisingly, better compressive strengths were obtained by replacing the aggregate fraction. CW ashes presented promising results for the substitution of aggregate in mortar and possibly in concrete. Copyright © 2010 Elsevier Ltd. All rights reserved.

Assessing fly ash treatment: Remediation and stabilization of heavy metals

KAUST Repository

Lima, A.T.

2010-12-17

Fly ashes from Municipal Solid Waste (MSW), straw (ST) and co-combustion of wood (CW) are here analyzed with the intent of reusing them. Two techniques are assessed, a remediation technique and a solidification/stabilization one. The removal of heavy metals from fly ashes through the electrodialytic process (EDR) has been tried out before. The goal of removing heavy metals has always been the reuse of fly ash, for instance in agricultural fields (BEK). The best removal rates are here summarized and some new results have been added. MSW fly ashes are still too hazardous after treatment to even consider application to the soil. ST ash is the only residue that gets concentrations low enough to be reused, but its fertilizing value might be questioned. An alternative reuse for the three ashes is here preliminary tested, the combination of fly ash with mortar. Fly ashes have been substituted by cement fraction or aggregate fraction. Surprisingly, better compressive strengths were obtained by replacing the aggregate fraction. CW ashes presented promising results for the substitution of aggregate in mortar and possibly in concrete. © 2010 Elsevier Ltd.

Assessing fly ash treatment: Remediation and stabilization of heavy metals

KAUST Repository

Lima, A.T.; Ottosen, Lisbeth M.; Ribeiro, Alexandra B.

2010-01-01

Fly ashes from Municipal Solid Waste (MSW), straw (ST) and co-combustion of wood (CW) are here analyzed with the intent of reusing them. Two techniques are assessed, a remediation technique and a solidification/stabilization one. The removal of heavy metals from fly ashes through the electrodialytic process (EDR) has been tried out before. The goal of removing heavy metals has always been the reuse of fly ash, for instance in agricultural fields (BEK). The best removal rates are here summarized and some new results have been added. MSW fly ashes are still too hazardous after treatment to even consider application to the soil. ST ash is the only residue that gets concentrations low enough to be reused, but its fertilizing value might be questioned. An alternative reuse for the three ashes is here preliminary tested, the combination of fly ash with mortar. Fly ashes have been substituted by cement fraction or aggregate fraction. Surprisingly, better compressive strengths were obtained by replacing the aggregate fraction. CW ashes presented promising results for the substitution of aggregate in mortar and possibly in concrete. © 2010 Elsevier Ltd.

The Effectiveness of Gaze-Contingent Control in Computer Games.

Science.gov (United States)

Orlov, Paul A; Apraksin, Nikolay

2015-01-01

Eye-tracking technology and gaze-contingent control in human-computer interaction have become an objective reality. This article reports on a series of eye-tracking experiments, in which we concentrated on one aspect of gaze-contingent interaction: Its effectiveness compared with mouse-based control in a computer strategy game. We propose a measure for evaluating the effectiveness of interaction based on "the time of recognition" the game unit. In this article, we use this measure to compare gaze- and mouse-contingent systems, and we present the analysis of the differences as a function of the number of game units. Our results indicate that performance of gaze-contingent interaction is typically higher than mouse manipulation in a visual searching task. When tested on 60 subjects, the results showed that the effectiveness of gaze-contingent systems over 1.5 times higher. In addition, we obtained that eye behavior stays quite stabile with or without mouse interaction. © The Author(s) 2015.

TabletGaze: Unconstrained Appearance-based Gaze Estimation in Mobile Tablets

OpenAIRE

Huang, Qiong; Veeraraghavan, Ashok; Sabharwal, Ashutosh

2015-01-01

We study gaze estimation on tablets, our key design goal is uncalibrated gaze estimation using the front-facing camera during natural use of tablets, where the posture and method of holding the tablet is not constrained. We collected the first large unconstrained gaze dataset of tablet users, labeled Rice TabletGaze dataset. The dataset consists of 51 subjects, each with 4 different postures and 35 gaze locations. Subjects vary in race, gender and in their need for prescription glasses, all o...

Structural and Mechanical Characterization of Sustainable Composites Based on Recycled and Stabilized Fly Ash

Directory of Open Access Journals (Sweden)

Stefano Besco

2014-08-01

Full Text Available This paper reports the results on the use of an innovative inert, based on stabilized fly ash from municipal solid waste incineration as a filler for polypropylene. The starting material, which contains large quantities of leachable Pb and Zn, was stabilized by means of an innovative process using rice husk ash as a waste silica source, together with other fly ashes, such as coal fly ash and flue gas desulfurization residues. The use of all waste materials to obtain a new filler makes the proposed technology extremely sustainable and competitive. The new composites, obtained by using the stabilized material as a filler for polypropylene, were characterized and their mechanical properties were also investigated. A comparison with a traditional polypropylene and calcium carbonate based compound was also done. This research activity was realized in the frame of the COSMOS-RICE project, financed by the EU Commission.

The Stabilization of Weathered Dolerite Aggregates with Cement, Lime, and Lime Fly Ash for Pavement Construction

Directory of Open Access Journals (Sweden)

Felix N. Okonta

2014-01-01

Full Text Available An experimental program was performed on weathered dolerite specimens stabilized by adding varying percentages of cement (4, 8, 12, and 16 % and lime (6 and 12 % and a combination of lime and fly ash (6% lime + 12% Fly ash and 12% lime + 12% Fly ash % by dry weight of soil. The strength was examined under three different curing methods, namely, membrane curing (MBC, alternate moist-air curing (MAC, and water curing (WAC, by conducting unconfined compressive strength (UCS tests. Simple polynomial and linear functions (regression models were used to define the relationships between the variables investigated. Membrane curing (MBC gave results close enough to the water curing (WAC to indicate that it can be confidently used on the field during pavement construction. From the results obtained, for class B (interurban collector and major rural roads pavement construction, addition of 8% cement was recommended for road base construction with stabilized WDA. Also the addition of 12 + 12% Lime and Fly Ash was recommended for road subbase construction with stabilized WDA. Stabilized WDA against the prejudiced myths would perform satisfactorily for base and subbase construction in both heavily trafficked and low volume roads with economic quantities of cement, lime, and fly ash in South Africa.

E-gaze : create gaze communication for peoplewith visual disability

NARCIS (Netherlands)

Qiu, S.; Osawa, H.; Hu, J.; Rauterberg, G.W.M.

2015-01-01

Gaze signals are frequently used by the sighted in social interactions as visual cues. However, these signals and cues are hardly accessible for people with visual disability. A conceptual design of E-Gaze glasses is proposed, assistive to create gaze communication between blind and sighted people

Eye Gaze Controlled Projected Display in Automotive and Military Aviation Environments

Directory of Open Access Journals (Sweden)

Gowdham Prabhakar

2018-01-01

Full Text Available This paper presents an eye gaze controlled projected display that can be used in aviation and automotive environment as a head up display. We have presented details of the hardware and software used in developing the display and an algorithm to improve performance of point and selection tasks in eye gaze controlled graphical user interface. The algorithm does not require changing layout of an interface; it rather puts a set of hotspots on clickable targets using a Simulated Annealing algorithm. Four user studies involving driving and flight simulators have found that the proposed projected display can improve driving and flying performance and significantly reduce pointing and selection times for secondary mission control tasks compared to existing interaction systems.

A theoretical analysis of pitch stability during gliding in flying snakes.

Science.gov (United States)

Jafari, Farid; Ross, Shane D; Vlachos, Pavlos P; Socha, John J

2014-06-01

Flying snakes use their entire body as a continuously morphing 'wing' to produce lift and shallow their glide trajectory. Their dominant behavior during gliding is aerial undulation, in which lateral waves are sent posteriorly down the body. This highly dynamic behavior, which is unique among animal gliders, should have substantial effects on the flight dynamics and stability of the snakes, resulting from the continuous redistribution of mass and aerodynamic forces. In this study, we develop two-dimensional theoretical models to assess the stability characteristics of snakes in the pitch direction. Previously measured force coefficients are used to simulate aerodynamic forces acting on the models, and undulation is simulated by varying mass. Model 1 is a simple three-airfoil representation of the snake's body that possesses a passively stable equilibrium solution, whose basin of stability contains initial conditions observed in experimental gliding trajectories. Model 2 is more sophisticated, with more degrees of freedom allowing for postural changes to better represent the snake's real kinematics; in addition, a restoring moment is added to simulate potential active control. The application of static and dynamic stability criteria show that Model 2 is passively unstable, but can be stabilized with a restoring moment. Overall, these models suggest that undulation does not contribute to stability in pitch, and that flying snakes require a closed-loop control system formed around a passively stable dynamical framework.

Solidification/stabilization of fly and bottom ash from medical waste incineration facility.

Science.gov (United States)

Anastasiadou, Kalliopi; Christopoulos, Konstantinos; Mousios, Epameinontas; Gidarakos, Evangelos

2012-03-15

In the present work, the stabilization/solidification of fly and bottom ash generated from incinerated hospital waste was studied. The objectives of the solidification/stabilization treatment were therefore to reduce the leachability of the heavy metals present in these materials so as to permit their disposal in a sanitary landfill requiring only a lower degree of environmental protection. Another objective of the applied treatment was to increase the mechanical characteristics of the bottom ash using different amounts of Ordinary Portland Cement (OPC) as a binder. The solidified matrix showed that the cement is able to immobilize the heavy metals found in fly and bottom ash. The TCLP leachates of the untreated fly ash contain high concentrations of Zn (13.2 mg/l) and Pb (5.21 mg/l), and lesser amounts of Cr, Fe, Ni, Cu, Cd and Ba. Cement-based solidification exhibited a compressive strength of 0.55-16.12 MPa. The strength decreased as the percentage of cement loading was reduced; the compressive strength was 2.52-12.7 MPa for 60% cement mixed with 40% fly ash and 6.62-16.12 MPa for a mixture of 60% cement and 40% bottom ash. The compressive strength reduced to 0.55-1.30 MPa when 30% cement was mixed with 70% fly ash, and to 0.90-7.95 MPa when 30% cement was mixed with 70% bottom ash, respectively. Copyright © 2011 Elsevier B.V. All rights reserved.

Rotational accelerations stabilize leading edge vortices on revolving fly wings.

Science.gov (United States)

Lentink, David; Dickinson, Michael H

2009-08-01

The aerodynamic performance of hovering insects is largely explained by the presence of a stably attached leading edge vortex (LEV) on top of their wings. Although LEVs have been visualized on real, physically modeled, and simulated insects, the physical mechanisms responsible for their stability are poorly understood. To gain fundamental insight into LEV stability on flapping fly wings we expressed the Navier-Stokes equations in a rotating frame of reference attached to the wing's surface. Using these equations we show that LEV dynamics on flapping wings are governed by three terms: angular, centripetal and Coriolis acceleration. Our analysis for hovering conditions shows that angular acceleration is proportional to the inverse of dimensionless stroke amplitude, whereas Coriolis and centripetal acceleration are proportional to the inverse of the Rossby number. Using a dynamically scaled robot model of a flapping fruit fly wing to systematically vary these dimensionless numbers, we determined which of the three accelerations mediate LEV stability. Our force measurements and flow visualizations indicate that the LEV is stabilized by the ;quasi-steady' centripetal and Coriolis accelerations that are present at low Rossby number and result from the propeller-like sweep of the wing. In contrast, the unsteady angular acceleration that results from the back and forth motion of a flapping wing does not appear to play a role in the stable attachment of the LEV. Angular acceleration is, however, critical for LEV integrity as we found it can mediate LEV spiral bursting, a high Reynolds number effect. Our analysis and experiments further suggest that the mechanism responsible for LEV stability is not dependent on Reynolds number, at least over the range most relevant for insect flight (100wind turbines at much higher Reynolds numbers suggest that even large flying animals could potentially exploit LEV-based force augmentation during slow hovering flight, take-offs or landing

Remote gaze tracking system for 3D environments.

Science.gov (United States)

Congcong Liu; Herrup, Karl; Shi, Bertram E

2017-07-01

Eye tracking systems are typically divided into two categories: remote and mobile. Remote systems, where the eye tracker is located near the object being viewed by the subject, have the advantage of being less intrusive, but are typically used for tracking gaze points on fixed two dimensional (2D) computer screens. Mobile systems such as eye tracking glasses, where the eye tracker are attached to the subject, are more intrusive, but are better suited for cases where subjects are viewing objects in the three dimensional (3D) environment. In this paper, we describe how remote gaze tracking systems developed for 2D computer screens can be used to track gaze points in a 3D environment. The system is non-intrusive. It compensates for small head movements by the user, so that the head need not be stabilized by a chin rest or bite bar. The system maps the 3D gaze points of the user onto 2D images from a scene camera and is also located remotely from the subject. Measurement results from this system indicate that it is able to estimate gaze points in the scene camera to within one degree over a wide range of head positions.

Beyond waste: new sustainable fillers from fly ashes stabilization, obtained by low cost raw materials

Directory of Open Access Journals (Sweden)

N. Rodella

2016-09-01

Full Text Available A sustainable economy can be achieved only by assessing processes finalized to optimize the use of resources. Waste can be a relevant source of energy thanks to energy-from-waste processes. Concerns regarding the toxic fly ashes can be solved by transforming them into resource as recycled materials. The commitment to recycle is driven by the need to conserve natural resources, reduce imports of raw materials, save landfill space and reduce pollution. A new method to stabilize fly ash from Municipal Solid Waste Incinerator (MSWI at room temperature has been developed thanks to COSMOS-RICE LIFE+ project (www.cosmos-rice.csmt.eu. This process is based on a chemical reaction that occurs properly mixing three waste fly ashes with rice husk ash, an agricultural by-product. COSMOS inert can replace critical raw materials (i.e. silica, fluorspar, clays, bentonite, antimony and alumina as filler. Moreover the materials employed in the stabilization procedure may be not available in all areas. This paper investigates the possibility of substituting silica fume with corresponding condensed silica fume and to substitute flue-gas desulfurization (FGD residues with low-cost calcium hydroxide powder. The removal of coal fly ash was also considered. The results will be presented and a possible substitution of the materials to stabilize fly ash will be discussed.

A theoretical analysis of pitch stability during gliding in flying snakes

International Nuclear Information System (INIS)

Jafari, Farid; Ross, Shane D; Socha, John J; Vlachos, Pavlos P

2014-01-01

Flying snakes use their entire body as a continuously morphing ‘wing’ to produce lift and shallow their glide trajectory. Their dominant behavior during gliding is aerial undulation, in which lateral waves are sent posteriorly down the body. This highly dynamic behavior, which is unique among animal gliders, should have substantial effects on the flight dynamics and stability of the snakes, resulting from the continuous redistribution of mass and aerodynamic forces. In this study, we develop two-dimensional theoretical models to assess the stability characteristics of snakes in the pitch direction. Previously measured force coefficients are used to simulate aerodynamic forces acting on the models, and undulation is simulated by varying mass. Model 1 is a simple three-airfoil representation of the snake’s body that possesses a passively stable equilibrium solution, whose basin of stability contains initial conditions observed in experimental gliding trajectories. Model 2 is more sophisticated, with more degrees of freedom allowing for postural changes to better represent the snake’s real kinematics; in addition, a restoring moment is added to simulate potential active control. The application of static and dynamic stability criteria show that Model 2 is passively unstable, but can be stabilized with a restoring moment. Overall, these models suggest that undulation does not contribute to stability in pitch, and that flying snakes require a closed-loop control system formed around a passively stable dynamical framework. (papers)

Utilization of fly ash for stabilization/solidification of heavy metal contaminated soils

Energy Technology Data Exchange (ETDEWEB)

Dermatas, D.; Meng, X. [Stevens Inst. of Technology, Hoboken, NJ (United States)

1995-12-01

Pozzolanic-based stabilization/solidification (S/S) is an effective, yet economic technological alternative to immobilize heavy metals in contaminated soils and sludges. Fly ash waste materials were used along with quicklime (CaO) to immobilize lead, trivalent and hexavalent chromium present in contaminated clayey sand soils. The degree of heavy metal immobilization was evaluated using the Toxicity Characteristic Leaching Procedure (TCLP) as well as controlled extraction experiments. These leaching test results along with X-ray diffraction (XRD), scanning electron microscope and energy dispersive x-ray (SEM-EDX) analyses were also implemented to elucidate the mechanisms responsible for immobilization of the heavy metals under study. Finally, the reusability of the stabilized waste forms in construction applications was also investigated by performing unconfined compressive strength and swell tests. Results suggest that the controlling mechanism for both lead and hexavalent chromium immobilization is surface adsorption, whereas for trivalent chromium it is hydroxide precipitation. Addition of fly ash to the contaminated soils effectively reduced heavy metal leachability well below the non-hazardous regulatory limits. However, quicklime addition was necessary in order to attain satisfactory immobilization levels. Overall, fly ash addition increases the immobilization pH region for all heavy metals tested, and significantly improves the stress-strain properties of the treated solids, thus allowing their reuse as readily available construction materials. The only potential problem associated with this quicklime/fly ash treatment is the excessive formation of the pozzolanic product ettringite in the presence of sulfates. Ettringite, when brought in contact with water, may cause significant swelling and subsequent deterioration of the stabilized matrix. Addition of minimum amounts of barium hydroxide was shown to effectively eliminate ettringite formation.

Long term evaluation and identification of the proper testing program for ASTM Class C fly ash stabilized soils : technical summary.

Science.gov (United States)

1993-07-01

The objectives of this research were to further evaluate the characteristics of locally produced fly ash and to develop test procedures which would expedite the evaluation of fly ash stabilized soils. Because cement and lime stabilization techniques ...

Single gaze gestures

DEFF Research Database (Denmark)

Møllenbach, Emilie; Lilholm, Martin; Gail, Alastair

2010-01-01

This paper examines gaze gestures and their applicability as a generic selection method for gaze-only controlled interfaces. The method explored here is the Single Gaze Gesture (SGG), i.e. gestures consisting of a single point-to-point eye movement. Horizontal and vertical, long and short SGGs were...

Gaze beats mouse

DEFF Research Database (Denmark)

Mateo, Julio C.; San Agustin, Javier; Hansen, John Paulin

2008-01-01

Facial EMG for selection is fast, easy and, combined with gaze pointing, it can provide completely hands-free interaction. In this pilot study, 5 participants performed a simple point-and-select task using mouse or gaze for pointing and a mouse button or a facial-EMG switch for selection. Gaze...

Advanced Techniques for Assessment of Postural and Locomotor Ataxia, Spatial Orientation, and Gaze Stability

Science.gov (United States)

Wall, Conrad., III

1999-01-01

In addition to adapting to microgravity, major neurovestibular problems of space flight include postflight difficulties with standing, walking, turning corners, and other activities that require stable upright posture and gaze stability. These difficulties inhibit astronauts' ability to stand or escape from their vehicle during emergencies. The long-ter7n goal of the NSBRI is the development of countermeasures to ameliorate the effects of long duration space flight. These countermeasures must be tested with valid and reliable tools. This project aims to develop quantitative, parametric approaches for assessing gaze stability and spatial orientation during normal gait and when gait is perturbed. Two of this year's most important findings concern head fixation distance and ideal trajectory analysis. During a normal cycle of walking the head moves up and down linearly. A simultaneous angular pitching motion of the head keeps it aligned toward an imaginary point in space at a distance of about one meter in front of a subject and along the line of march. This distance is called the head fixation distance. Head fixation distance provides the fundamental framework necessary for understanding the functional significance of the vestibular reflexes that couple head motion to eye motion. This framework facilitates the intelligent design of counter-measures for the effects of exposure to microgravity upon the vestibular ocular reflexes. Ideal trajectory analysis is a simple candidate countermeasure based upon quantifying body sway during repeated up and down stair stepping. It provides one number that estimates the body sway deviation from an ideal sinusoidal body sway trajectory normalized on the subject's height. This concept has been developed with NSBRI funding in less than one year. These findings are explained in more detail below. Compared to assessments of the vestibuo-ocular reflex, analysis of vestibular effects on locomotor function is relatively less well developed

New perspectives in gaze sensitivity research.

Science.gov (United States)

Davidson, Gabrielle L; Clayton, Nicola S

2016-03-01

Attending to where others are looking is thought to be of great adaptive benefit for animals when avoiding predators and interacting with group members. Many animals have been reported to respond to the gaze of others, by co-orienting their gaze with group members (gaze following) and/or responding fearfully to the gaze of predators or competitors (i.e., gaze aversion). Much of the literature has focused on the cognitive underpinnings of gaze sensitivity, namely whether animals have an understanding of the attention and visual perspectives in others. Yet there remain several unanswered questions regarding how animals learn to follow or avoid gaze and how experience may influence their behavioral responses. Many studies on the ontogeny of gaze sensitivity have shed light on how and when gaze abilities emerge and change across development, indicating the necessity to explore gaze sensitivity when animals are exposed to additional information from their environment as adults. Gaze aversion may be dependent upon experience and proximity to different predator types, other cues of predation risk, and the salience of gaze cues. Gaze following in the context of information transfer within social groups may also be dependent upon experience with group-members; therefore we propose novel means to explore the degree to which animals respond to gaze in a flexible manner, namely by inhibiting or enhancing gaze following responses. We hope this review will stimulate gaze sensitivity research to expand beyond the narrow scope of investigating underlying cognitive mechanisms, and to explore how gaze cues may function to communicate information other than attention.

A GazeWatch Prototype

DEFF Research Database (Denmark)

Paulin Hansen, John; Biermann, Florian; Møllenbach, Emile

2015-01-01

We demonstrate potentials of adding a gaze tracking unit to a smartwatch, allowing hands-free interaction with the watch itself and control of the environment. Users give commands via gaze gestures, i.e. looking away and back to the GazeWatch. Rapid presentation of single words on the watch displ...... provides a rich and effective textual interface. Finally, we exemplify how the GazeWatch can be used as a ubiquitous pointer on large displays....

Stabilization of heavy metals in MSWI fly ash using silica fume

Energy Technology Data Exchange (ETDEWEB)

Li, Xinying; Chen, Quanyuan [School of Environment Science and Engineering, Donghua University, Shanghai 201620 (China); State Environmental Protection Engineering Center for Pollution Treatment and Control in Textile Industry, Donghua University, Shanghai 201620 (China); Zhou, Yasu [School of Environment Science and Engineering, Donghua University, Shanghai 201620 (China); Tyrer, Mark [Mineral Industry Research Organisation, Solihull B37 7HB (United Kingdom); Yu, Yang [School of Environment Science and Engineering, Donghua University, Shanghai 201620 (China)

2014-12-15

Highlights: • The stabilization of heavy metals in MSWI fly ash was investigated. • The addition of silica fume effectively reduced the leaching of Pb and Cd. • The relation of solid phase transformation and leaching behavior of heavy metals was discussed. - Abstract: The objective of this work was to investigate the feasibility and effectiveness of silica fume on stabilizing heavy metals in municipal solid waste incineration (MSWI) fly ash. In addition to compressive strength measurements, hydrated pastes were characterized by X-ray diffraction (XRD), thermal-analyses (DTA/TG), and MAS NMR ({sup 27}Al and {sup 29}Si) techniques. It was found that silica fume additions could effectively reduce the leaching of toxic heavy metals. At the addition of 20% silica fume, leaching concentrations for Cu, Pb and Zn of the hydrated paste cured for 7 days decreased from 0.32 mg/L to 0.05 mg/L, 40.99 mg/L to 4.40 mg/L, and 6.96 mg/L to 0.21 mg/L compared with the MSWI fly ash. After curing for 135 days, Cd and Pb in the leachates were not detected, while Cu and Zn concentrations decreased to 0.02 mg/L and 0.03 mg/L. The speciation of Pb and Cd by the modified version of the European Community Bureau of Reference (BCR) extractions showed that these metals converted into more stable state in hydrated pastes of MSWI fly ash in the presence of silica fume. Although exchangeable and weak-acid soluble fractions of Cu and Zn increased with hydration time, silica fume addition of 10% can satisfy the requirement of detoxification for heavy metals investigated in terms of the identification standard of hazardous waste of China.

Follow My Eyes: The Gaze of Politicians Reflexively Captures the Gaze of Ingroup Voters

Science.gov (United States)

Liuzza, Marco Tullio; Cazzato, Valentina; Vecchione, Michele; Crostella, Filippo; Caprara, Gian Vittorio; Aglioti, Salvatore Maria

2011-01-01

Studies in human and non-human primates indicate that basic socio-cognitive operations are inherently linked to the power of gaze in capturing reflexively the attention of an observer. Although monkey studies indicate that the automatic tendency to follow the gaze of a conspecific is modulated by the leader-follower social status, evidence for such effects in humans is meager. Here, we used a gaze following paradigm where the directional gaze of right- or left-wing Italian political characters could influence the oculomotor behavior of ingroup or outgroup voters. We show that the gaze of Berlusconi, the right-wing leader currently dominating the Italian political landscape, potentiates and inhibits gaze following behavior in ingroup and outgroup voters, respectively. Importantly, the higher the perceived similarity in personality traits between voters and Berlusconi, the stronger the gaze interference effect. Thus, higher-order social variables such as political leadership and affiliation prepotently affect reflexive shifts of attention. PMID:21957479

Gaze Tracking Through Smartphones

DEFF Research Database (Denmark)

Skovsgaard, Henrik; Hansen, John Paulin; Møllenbach, Emilie

Mobile gaze trackers embedded in smartphones or tablets provide a powerful personal link to game devices, head-mounted micro-displays, pc´s, and TV’s. This link may offer a main road to the mass market for gaze interaction, we suggest.......Mobile gaze trackers embedded in smartphones or tablets provide a powerful personal link to game devices, head-mounted micro-displays, pc´s, and TV’s. This link may offer a main road to the mass market for gaze interaction, we suggest....

Is gaze following purely reflexive or goal-directed instead? Revisiting the automaticity of orienting attention by gaze cues.

Science.gov (United States)

Ricciardelli, Paola; Carcagno, Samuele; Vallar, Giuseppe; Bricolo, Emanuela

2013-01-01

Distracting gaze has been shown to elicit automatic gaze following. However, it is still debated whether the effects of perceived gaze are a simple automatic spatial orienting response or are instead sensitive to the context (i.e. goals and task demands). In three experiments, we investigated the conditions under which gaze following occurs. Participants were instructed to saccade towards one of two lateral targets. A face distracter, always present in the background, could gaze towards: (a) a task-relevant target--("matching" goal-directed gaze shift)--congruent or incongruent with the instructed direction, (b) a task-irrelevant target, orthogonal to the one instructed ("non-matching" goal-directed gaze shift), or (c) an empty spatial location (no-goal-directed gaze shift). Eye movement recordings showed faster saccadic latencies in correct trials in congruent conditions especially when the distracting gaze shift occurred before the instruction to make a saccade. Interestingly, while participants made a higher proportion of gaze-following errors (i.e. errors in the direction of the distracting gaze) in the incongruent conditions when the distracter's gaze shift preceded the instruction onset indicating an automatic gaze following, they never followed the distracting gaze when it was directed towards an empty location or a stimulus that was never the target. Taken together, these findings suggest that gaze following is likely to be a product of both automatic and goal-driven orienting mechanisms.

Conjugate Gaze Palsies

Science.gov (United States)

... version Home Brain, Spinal Cord, and Nerve Disorders Cranial Nerve Disorders Conjugate Gaze Palsies Horizontal gaze palsy Vertical ... Version. DOCTORS: Click here for the Professional Version Cranial Nerve Disorders Overview of the Cranial Nerves Internuclear Ophthalmoplegia ...

Gazes

DEFF Research Database (Denmark)

Khawaja, Iram

, and the different strategies of positioning they utilize are studied and identified. The first strategy is to confront stereotyping prejudices and gazes, thereby attempting to position oneself in a counteracting way. The second is to transform and try to normalise external characteristics, such as clothing...... and other symbols that indicate Muslimness. A third strategy is to play along and allow the prejudice in question to remain unchallenged. A fourth is to join and participate in religious communities and develop an alternate sense of belonging to a wider community of Muslims. The concept of panoptical gazes...

Eye Movements in Gaze Interaction

DEFF Research Database (Denmark)

Møllenbach, Emilie; Hansen, John Paulin; Lillholm, Martin

2013-01-01

Gaze as a sole input modality must support complex navigation and selection tasks. Gaze interaction combines specific eye movements and graphic display objects (GDOs). This paper suggests a unifying taxonomy of gaze interaction principles. The taxonomy deals with three types of eye movements...

Fearful gaze cueing: gaze direction and facial expression independently influence overt orienting responses in 12-month-olds.

Directory of Open Access Journals (Sweden)

Reiko Matsunaka

Full Text Available Gaze direction cues and facial expressions have been shown to influence object processing in infants. For example, infants around 12 months of age utilize others' gaze directions and facial expressions to regulate their own behaviour toward an ambiguous target (i.e., social referencing. However, the mechanism by which social signals influence overt orienting in infants is unclear. The present study examined the effects of static gaze direction cues and facial expressions (neutral vs. fearful on overt orienting using a gaze-cueing paradigm in 6- and 12-month-old infants. Two experiments were conducted: in Experiment 1, a face with a leftward or rightward gaze direction was used as a cue, and a face with a forward gaze direction was added in Experiment 2. In both experiments, an effect of facial expression was found in 12-month-olds; no effect was found in 6-month-olds. Twelve-month-old infants exhibited more rapid overt orienting in response to fearful expressions than neutral expressions, irrespective of gaze direction. These findings suggest that gaze direction information and facial expressions independently influence overt orienting in infants, and the effect of facial expression emerges earlier than that of static gaze direction. Implications for the development of gaze direction and facial expression processing systems are discussed.

Eye gaze in intelligent user interfaces gaze-based analyses, models and applications

CERN Document Server

Nakano, Yukiko I; Bader, Thomas

2013-01-01

Remarkable progress in eye-tracking technologies opened the way to design novel attention-based intelligent user interfaces, and highlighted the importance of better understanding of eye-gaze in human-computer interaction and human-human communication. For instance, a user's focus of attention is useful in interpreting the user's intentions, their understanding of the conversation, and their attitude towards the conversation. In human face-to-face communication, eye gaze plays an important role in floor management, grounding, and engagement in conversation.Eye Gaze in Intelligent User Interfac

Gazing and Performing

DEFF Research Database (Denmark)

Larsen, Jonas; Urry, John

2011-01-01

The Tourist Gaze [Urry J, 1990 (Sage, London)] is one of the most discussed and cited tourism books (with about 4000 citations on Google scholar). Whilst wide ranging in scope, the book is known for the Foucault-inspired concept of the tourist gaze that brings out the fundamentally visual and image...

Gaze as a biometric

Science.gov (United States)

Yoon, Hong-Jun; Carmichael, Tandy R.; Tourassi, Georgia

2014-03-01

Two people may analyze a visual scene in two completely different ways. Our study sought to determine whether human gaze may be used to establish the identity of an individual. To accomplish this objective we investigated the gaze pattern of twelve individuals viewing still images with different spatial relationships. Specifically, we created 5 visual "dotpattern" tests to be shown on a standard computer monitor. These tests challenged the viewer's capacity to distinguish proximity, alignment, and perceptual organization. Each test included 50 images of varying difficulty (total of 250 images). Eye-tracking data were collected from each individual while taking the tests. The eye-tracking data were converted into gaze velocities and analyzed with Hidden Markov Models to develop personalized gaze profiles. Using leave-one-out cross-validation, we observed that these personalized profiles could differentiate among the 12 users with classification accuracy ranging between 53% and 76%, depending on the test. This was statistically significantly better than random guessing (i.e., 8.3% or 1 out of 12). Classification accuracy was higher for the tests where the users' average gaze velocity per case was lower. The study findings support the feasibility of using gaze as a biometric or personalized biomarker. These findings could have implications in Radiology training and the development of personalized e-learning environments.

Gaze as a biometric

Energy Technology Data Exchange (ETDEWEB)

Yoon, Hong-Jun [ORNL; Carmichael, Tandy [Tennessee Technological University; Tourassi, Georgia [ORNL

2014-01-01

Two people may analyze a visual scene in two completely different ways. Our study sought to determine whether human gaze may be used to establish the identity of an individual. To accomplish this objective we investigated the gaze pattern of twelve individuals viewing different still images with different spatial relationships. Specifically, we created 5 visual dot-pattern tests to be shown on a standard computer monitor. These tests challenged the viewer s capacity to distinguish proximity, alignment, and perceptual organization. Each test included 50 images of varying difficulty (total of 250 images). Eye-tracking data were collected from each individual while taking the tests. The eye-tracking data were converted into gaze velocities and analyzed with Hidden Markov Models to develop personalized gaze profiles. Using leave-one-out cross-validation, we observed that these personalized profiles could differentiate among the 12 users with classification accuracy ranging between 53% and 76%, depending on the test. This was statistically significantly better than random guessing (i.e., 8.3% or 1 out of 12). Classification accuracy was higher for the tests where the users average gaze velocity per case was lower. The study findings support the feasibility of using gaze as a biometric or personalized biomarker. These findings could have implications in Radiology training and the development of personalized e-learning environments.

The Epistemology of the Gaze

DEFF Research Database (Denmark)

Kramer, Mette

2007-01-01

In psycho-semiotic film theory the gaze is often considered to be a straitjacket for the female spectator. If we approach the gaze from an empiric so-called ‘naturalised’ lens, it is possible to regard the gaze as a functional devise through which the spectator can obtain knowledge essential for ...... for her self-preservation....

AmbiGaze : direct control of ambient devices by gaze

OpenAIRE

Velloso, Eduardo; Wirth, Markus; Weichel, Christian; Abreu Esteves, Augusto Emanuel; Gellersen, Hans-Werner Georg

2016-01-01

Eye tracking offers many opportunities for direct device control in smart environments, but issues such as the need for calibration and the Midas touch problem make it impractical. In this paper, we propose AmbiGaze, a smart environment that employs the animation of targets to provide users with direct control of devices by gaze only through smooth pursuit tracking. We propose a design space of means of exposing functionality through movement and illustrate the concept through four prototypes...

Economic evaluation of flying-qualities design criteria for a transport configured with relaxed static stability

Science.gov (United States)

Sliwa, S. M.

1980-01-01

Direct constrained parameter optimization was used to optimally size a medium range transport for minimum direct operating cost. Several stability and control constraints were varied to study the sensitivity of the configuration to specifying the unaugmented flying qualities of transports designed to take maximum advantage of relaxed static stability augmentation systems. Additionally, a number of handling qualities related design constants were studied with respect to their impact on the design.

Gaze Stabilization Test Asymmetry Score as an Indicator of Previous Concussion in a Cohort of Collegiate Football Players.

Science.gov (United States)

Honaker, Julie A; Criter, Robin E; Patterson, Jessie N; Jones, Sherri M

2015-07-01

Vestibular dysfunction may lead to decreased visual acuity with head movements, which may impede athletic performance and result in injury. The purpose of this study was to test the hypothesis that athletes with history of concussion would have differences in gaze stabilization test (GST) as compared with those without a history of concussion. Cross-sectional, descriptive. University Athletic Medicine Facility. Fifteen collegiate football players with a history of concussion, 25 collegiate football players without a history of concussion. Participants completed the dizziness handicap inventory (DHI), static visual acuity, perception time test, active yaw plane GST, stability evaluation test (SET), and a bedside oculomotor examination. Independent samples t test was used to compare GST, SET, and DHI scores per group, with Bonferroni-adjusted alpha at P history of concussion. The results support further research on the use of GST for sport-related concussion evaluation and monitoring. Inclusion of objective vestibular tests in the concussion protocol may reveal the presence of peripheral vestibular or visual-vestibular deficits. Therefore, the GST may add an important perspective on the effects of concussion.

Postural control and head stability during natural gaze behaviour in 6- to 12-year-old children.

Science.gov (United States)

Schärli, A M; van de Langenberg, R; Murer, K; Müller, R M

2013-06-01

We investigated how the influence of natural exploratory gaze behaviour on postural control develops from childhood into adulthood. In a cross-sectional design, we compared four age groups: 6-, 9-, 12-year-olds and young adults. Two experimental trials were performed: quiet stance with a fixed gaze (fixed) and quiet stance with natural exploratory gaze behaviour (exploratory). The latter was elicited by having participants watch an animated short film on a large screen in front of them. 3D head rotations in space and centre of pressure (COP) excursions on the ground plane were measured. Across conditions, both head rotation and COP displacement decreased with increasing age. Head movement was greater in the exploratory condition in all age groups. In all children-but not in adults-COP displacement was markedly greater in the exploratory condition. Bivariate correlations across groups showed highly significant positive correlations between COP displacement in ML direction and head rotation in yaw, roll, and pitch in both conditions. The regularity of COP displacements did not show a clear developmental trend, which indicates that COP dynamics were qualitatively similar across age groups. Together, the results suggest that the contribution of head movement to eye-head saccades decreases with age and that head instability-in part resulting from such gaze-related head movements-is an important limiting factor in children's postural control. The lack of head stabilisation might particularly affect children in everyday activities in which both postural control and visual exploration are required.

Gazes and Performances

DEFF Research Database (Denmark)

Larsen, Jonas

ethnographic studies I spell out the embodied, hybridised, mobile and performative nature of tourist gazing especially with regard to tourist photography. The talk draws on my recent book Tourism, Performance and the Everyday: Consuming the Orient (Routledge, 2009, With M. Haldrup) and the substantially......Abstract: Recent literature has critiqued this notion of the 'tourist gaze' for reducing tourism to visual experiences 'sightseeing' and neglecting other senses and bodily experiences of doing tourism. A so-called 'performance turn' within tourist studies highlights how tourists experience places...... to onceptualise the corporeality of tourist bodies and the embodied actions of and interactions between tourist workers, tourists and 'locals' on various stages. It has been suggested that it is necessary to choose between gazing and performing as the tourism paradigm (Perkin and Thorns 2001). Rather than...

Eye gaze performance for children with severe physical impairments using gaze-based assistive technology-A longitudinal study.

Science.gov (United States)

Borgestig, Maria; Sandqvist, Jan; Parsons, Richard; Falkmer, Torbjörn; Hemmingsson, Helena

2016-01-01

Gaze-based assistive technology (gaze-based AT) has the potential to provide children affected by severe physical impairments with opportunities for communication and activities. This study aimed to examine changes in eye gaze performance over time (time on task and accuracy) in children with severe physical impairments, without speaking ability, using gaze-based AT. A longitudinal study with a before and after design was conducted on 10 children (aged 1-15 years) with severe physical impairments, who were beginners to gaze-based AT at baseline. Thereafter, all children used the gaze-based AT in daily activities over the course of the study. Compass computer software was used to measure time on task and accuracy with eye selection of targets on screen, and tests were performed with the children at baseline, after 5 months, 9-11 months, and after 15-20 months. Findings showed that the children improved in time on task after 5 months and became more accurate in selecting targets after 15-20 months. This study indicates that these children with severe physical impairments, who were unable to speak, could improve in eye gaze performance. However, the children needed time to practice on a long-term basis to acquire skills needed to develop fast and accurate eye gaze performance.

A Gaze Interactive Textual Smartwatch Interface

DEFF Research Database (Denmark)

Hansen, John Paulin; Biermann, Florian; Askø Madsen, Janus

2015-01-01

Mobile gaze interaction is challenged by inherent motor noise. We examined the gaze tracking accuracy and precision of twelve subjects wearing a gaze tracker on their wrist while standing and walking. Results suggest that it will be possible to detect whether people are glancing the watch, but no...

Utilize Cementitious High Carbon Fly Ash (CHCFA) to Stabilize Cold In-Place Recycled (CIR) Asphalt Pavement as Base Coarse

Energy Technology Data Exchange (ETDEWEB)

Wen, Haifang; Li, Xiaojun; Edil, Tuncer; O' Donnell, Jonathan; Danda, Swapna

2011-02-05

The purpose of this study was to evaluate the performance of cementitious high carbon fly ash (CHCFA) stabilized recycled asphalt pavement as a base course material in a real world setting. Three test road cells were built at MnROAD facility in Minnesota. These cells have the same asphalt surface layers, subbases, and subgrades, but three different base courses: conventional crushed aggregates, untreated recycled pavement materials (RPM), and CHCFA stabilized RPM materials. During and after the construction of the three cells, laboratory and field tests were carried out to characterize the material properties. The test results were used in the mechanistic-empirical pavement design guide (MEPDG) to predict the pavement performance. Based on the performance prediction, the life cycle analyses of cost, energy consumption, and greenhouse gasses were performed. The leaching impacts of these three types of base materials were compared. The laboratory and field tests showed that fly ash stabilized RPM had higher modulus than crushed aggregate and RPM did. Based on the MEPDG performance prediction, the service life of the Cell 79 containing fly ash stabilized RPM, is 23.5 years, which is about twice the service life (11 years) of the Cell 77 with RPM base, and about three times the service life (7.5 years) of the Cell 78 with crushed aggregate base. The life cycle analysis indicated that the usage of the fly ash stabilized RPM as the base of the flexible pavement can significantly reduce the life cycle cost, the energy consumption, the greenhouse gases emission. Concentrations of many trace elements, particularly those with relatively low water quality standards, diminish over time as water flows through the pavement profile. For many elements, concentrations below US water drinking water quality standards are attained at the bottom of the pavement profile within 2-4 pore volumes of flow.

Gaze interaction from bed

DEFF Research Database (Denmark)

Hansen, John Paulin; San Agustin, Javier; Jensen, Henrik Tomra Skovsgaard Hegner

2011-01-01

This paper presents a low-cost gaze tracking solution for bedbound people composed of free-ware tracking software and commodity hardware. Gaze interaction is done on a large wall-projected image, visible to all people present in the room. The hardware equipment leaves physical space free to assis...

Ternary blends containing demercurated lighting phosphor and MSWI fly ash as high-performance binders for stabilizing and recycling electroplating sludge.

Science.gov (United States)

Huang, Wu-Jang; Wu, Chia-Teng; Wu, Chang-En; Hsieh, Lin-Huey; Li, Chang-Chien; Lain, Chi-Yuan; Chu, Wei

2008-08-15

This paper describes the solidification and stabilization of electroplating sludge treated with a high-performance binder made from portland type-I cement, municipal solid waste incineration fly ash, and lighting phosphor powder (called as cement-fly ash-phosphor binder, CFP). The highest 28-day unconfined compressive strength of the CFP-treated paste was 816 kg/cm(2) at a ratio of cement to fly ash to lighting phosphor powder of 90:5:5; the strength of this composition also fulfilled the requirement of a high-strength concrete (>460 kg/cm(2) at 28 days). The CFP-stabilized sludge paste samples passed the Taiwanese EPA toxicity characteristic leaching procedure test and, therefore, could be used either as a building material or as a controlled low-strength material, depending on the sludge-to-CFP binder ratio.

Tuning of the Preferred Optic Flow Axes of Locust and Blowfly Visual Interneurons to Their Preferred Modes of Flight Behaviour

National Research Council Canada - National Science Library

Krapp, Holger G; Bomphrey, R. J; Laughlin, S. B; Taylor, G. K; Wuestenberg, D. G

2008-01-01

This report results from a contract tasking Imperial College London as follows: The grantee will investigate the sensory mechanisms of gaze stabilization and flight control on insects (flies and locusts...

Eye Gaze in Creative Sign Language

Science.gov (United States)

Kaneko, Michiko; Mesch, Johanna

2013-01-01

This article discusses the role of eye gaze in creative sign language. Because eye gaze conveys various types of linguistic and poetic information, it is an intrinsic part of sign language linguistics in general and of creative signing in particular. We discuss various functions of eye gaze in poetic signing and propose a classification of gaze…

Differences in gaze anticipation for locomotion with and without vision

Science.gov (United States)

Authié, Colas N.; Hilt, Pauline M.; N'Guyen, Steve; Berthoz, Alain; Bennequin, Daniel

2015-01-01

Previous experimental studies have shown a spontaneous anticipation of locomotor trajectory by the head and gaze direction during human locomotion. This anticipatory behavior could serve several functions: an optimal selection of visual information, for instance through landmarks and optic flow, as well as trajectory planning and motor control. This would imply that anticipation remains in darkness but with different characteristics. We asked 10 participants to walk along two predefined complex trajectories (limaçon and figure eight) without any cue on the trajectory to follow. Two visual conditions were used: (i) in light and (ii) in complete darkness with eyes open. The whole body kinematics were recorded by motion capture, along with the participant's right eye movements. We showed that in darkness and in light, horizontal gaze anticipates the orientation of the head which itself anticipates the trajectory direction. However, the horizontal angular anticipation decreases by a half in darkness for both gaze and head. In both visual conditions we observed an eye nystagmus with similar properties (frequency and amplitude). The main difference comes from the fact that in light, there is a shift of the orientations of the eye nystagmus and the head in the direction of the trajectory. These results suggest that a fundamental function of gaze is to represent self motion, stabilize the perception of space during locomotion, and to simulate the future trajectory, regardless of the vision condition. PMID:26106313

Perceptual Training in Beach Volleyball Defence: Different Effects of Gaze-Path Cueing on Gaze and Decision-Making

Directory of Open Access Journals (Sweden)

André eKlostermann

2015-12-01

Full Text Available For perceptual-cognitive skill training, a variety of intervention methods has been proposed, including the so-called colour-cueing method which aims on superior gaze-path learning by applying visual markers. However, recent findings challenge this method, especially, with regards to its actual effects on gaze behaviour. Consequently, after a preparatory study on the identification of appropriate visual cues for life-size displays, a perceptual-training experiment on decision-making in beach volleyball was conducted, contrasting two cueing interventions (functional vs. dysfunctional gaze path with a conservative control condition (anticipation-related instructions. Gaze analyses revealed learning effects for the dysfunctional group only. Regarding decision-making, all groups showed enhanced performance with largest improvements for the control group followed by the functional and the dysfunctional group. Hence, the results confirm cueing effects on gaze behaviour, but they also question its benefit for enhancing decision-making. However, before completely denying the method’s value, optimisations should be checked regarding, for instance, cueing-pattern characteristics and gaze-related feedback.

Wrist-worn pervasive gaze interaction

DEFF Research Database (Denmark)

Hansen, John Paulin; Lund, Haakon; Biermann, Florian

2016-01-01

This paper addresses gaze interaction for smart home control, conducted from a wrist-worn unit. First we asked ten people to enact the gaze movements they would propose for e.g. opening a door or adjusting the room temperature. On basis of their suggestions we built and tested different versions...... selection. Their subjective evaluations were positive with regard to the speed of the interaction. We conclude that gaze gesture input seems feasible for fast and brief remote control of smart home technology provided that robustness of tracking is improved....

Stabilization of Fly Ash Deposits through Selected Cereal Crops

Directory of Open Access Journals (Sweden)

Florica Morariu

2012-10-01

Full Text Available Fly ash, a waste product from burning coal in power plants, occupies important spaces and is a major harm forenvironment: water, air, soil and associated ecosystems. New deposits do not have available nutrients for plantgrowth. The study presents a process of stimulating growth of oats in deposits of fly ash, which eliminates listed.Phytostabilization of new deposit is fast after fertilization with sewage sludge-based compost in the presence/absence of native or modified volcanic tuff with grain species, Avena sativa L., and variety Lovrin 1. Experimentalstudies have shown the species adaptability to climatic conditions and a growth rate until the maturity correlated withtype of treatment of upper layers of fly ash deposit. Fly ash with sewage sludge compost treatment 50 t/hadetermined the growth with 75% of the amount of grains vs. the amount of grains harvested from untreated fly ash.Fly ash with sewage sludge compost mixed with modified indigenous volcanic tuff 2.5 t/ha treatment determined thegrowth with 80% vs. the amount of grains harvested from untreated fly ash. If oat straw harvested from fertilizedvariant without modified indigenous volcanic tuff increases in weight are 30% and for fertilized variant in thepresence of tuff increases in weight are 39.8% vs. quantities harvested from untreated fly ash.

Creating Gaze Annotations in Head Mounted Displays

DEFF Research Database (Denmark)

Mardanbeigi, Diako; Qvarfordt, Pernilla

2015-01-01

To facilitate distributed communication in mobile settings, we developed GazeNote for creating and sharing gaze annotations in head mounted displays (HMDs). With gaze annotations it possible to point out objects of interest within an image and add a verbal description. To create an annota- tion...

Effect of class F fly ash on fine sand compaction through soil stabilization.

Science.gov (United States)

Mahvash, Siavash; López-Querol, Susana; Bahadori-Jahromi, Ali

2017-03-01

This paper presents the results of an experimental investigation carried out to evaluate the effect of fly ash (FA) on fine sand compaction and its suitability as a material for embankments. The literature review demonstrates the lack of research on stabilization of sandy material using FA. The study is concerned with the role of FA content in stabilized soil physical characteristics. The main aim of this paper is to determine the optimum quantity of FA content for stabilization of this type of soil. This is achieved through particle size distribution and compaction (standard proctor) tests. The sand was stabilized with three proportions of FA (5%, 10% and 15%) and constant cement content of 3% was used as an activator. For better comparison, the sand was also stabilized by 3% cement only so that the effect of FA could be observed more clearly. The results were in line with the literature for other types of soil, i.e. as the % of FA increases, reduction in maximum dry density and higher optimum moisture content were observed.

Effect of class F fly ash on fine sand compaction through soil stabilization

Directory of Open Access Journals (Sweden)

Siavash Mahvash

2017-03-01

Full Text Available This paper presents the results of an experimental investigation carried out to evaluate the effect of fly ash (FA on fine sand compaction and its suitability as a material for embankments. The literature review demonstrates the lack of research on stabilization of sandy material using FA. The study is concerned with the role of FA content in stabilized soil physical characteristics. The main aim of this paper is to determine the optimum quantity of FA content for stabilization of this type of soil. This is achieved through particle size distribution and compaction (standard proctor tests. The sand was stabilized with three proportions of FA (5%, 10% and 15% and constant cement content of 3% was used as an activator. For better comparison, the sand was also stabilized by 3% cement only so that the effect of FA could be observed more clearly. The results were in line with the literature for other types of soil, i.e. as the % of FA increases, reduction in maximum dry density and higher optimum moisture content were observed.

Strategies for the stabilization of longitudinal forward flapping flight revealed using a dynamically-scaled robotic fly

International Nuclear Information System (INIS)

Elzinga, Michael J; Van Breugel, Floris; Dickinson, Michael H

2014-01-01

The ability to regulate forward speed is an essential requirement for flying animals. Here, we use a dynamically-scaled robot to study how flapping insects adjust their wing kinematics to regulate and stabilize forward flight. The results suggest that the steady-state lift and thrust requirements at different speeds may be accomplished with quite subtle changes in hovering kinematics, and that these adjustments act primarily by altering the pitch moment. This finding is consistent with prior hypotheses regarding the relationship between body pitch and flight speed in fruit flies. Adjusting the mean stroke position of the wings is a likely mechanism for trimming the pitch moment at all speeds, whereas changes in the mean angle of attack may be required at higher speeds. To ensure stability, the flapping system requires additional pitch damping that increases in magnitude with flight speed. A compensatory reflex driven by fast feedback of pitch rate from the halteres could provide such damping, and would automatically exhibit gain scheduling with flight speed if pitch torque was regulated via changes in stroke deviation. Such a control scheme would provide an elegant solution for stabilization across a wide range of forward flight speeds. (paper)

The “Social Gaze Space”: A Taxonomy for Gaze-Based Communication in Triadic Interactions

Directory of Open Access Journals (Sweden)

Mathis Jording

2018-02-01

Full Text Available Humans substantially rely on non-verbal cues in their communication and interaction with others. The eyes represent a “simultaneous input-output device”: While we observe others and obtain information about their mental states (including feelings, thoughts, and intentions-to-act, our gaze simultaneously provides information about our own attention and inner experiences. This substantiates its pivotal role for the coordination of communication. The communicative and coordinative capacities – and their phylogenetic and ontogenetic impacts – become fully apparent in triadic interactions constituted in its simplest form by two persons and an object. Technological advances have sparked renewed interest in social gaze and provide new methodological approaches. Here we introduce the ‘Social Gaze Space’ as a new conceptual framework for the systematic study of gaze behavior during social information processing. It covers all possible categorical states, namely ‘partner-oriented,’ ‘object-oriented,’ ‘introspective,’ ‘initiating joint attention,’ and ‘responding joint attention.’ Different combinations of these states explain several interpersonal phenomena. We argue that this taxonomy distinguishes the most relevant interactional states along their distinctive features, and will showcase the implications for prominent social gaze phenomena. The taxonomy allows to identify research desiderates that have been neglected so far. We argue for a systematic investigation of these phenomena and discuss some related methodological issues.

Owners' direct gazes increase dogs' attention-getting behaviors.

Science.gov (United States)

Ohkita, Midori; Nagasawa, Miho; Kazutaka, Mogi; Kikusui, Takefumi

2016-04-01

This study examined whether dogs gain information about human's attention via their gazes and whether they change their attention-getting behaviors (i.e., whining and whimpering, looking at their owners' faces, pawing, and approaching their owners) in response to their owners' direct gazes. The results showed that when the owners gazed at their dogs, the durations of whining and whimpering and looking at the owners' faces were longer than when the owners averted their gazes. In contrast, there were no differences in duration of pawing and likelihood of approaching the owners between the direct and averted gaze conditions. Therefore, owners' direct gazes increased the behaviors that acted as distant signals and did not necessarily involve touching the owners. We suggest that dogs are sensitive to human gazes, and this sensitivity may act as attachment signals to humans, and may contribute to close relationships between humans and dogs. Copyright © 2016 Elsevier B.V. All rights reserved.

Impact of stride-coupled gaze shifts of walking blowflies on the neuronal representation of visual targets

Directory of Open Access Journals (Sweden)

Daniel eKress

2014-09-01

Full Text Available During locomotion animals rely heavily on visual cues gained from the environment to guide their behavior. Examples are basic behaviors like collision avoidance or the approach to a goal. The saccadic gaze strategy of flying flies, which separates translational from rotational phases of locomotion, has been suggested to facilitate the extraction of environmental information, because only image flow evoked by translational self-motion contains relevant distance information about the surrounding world. In contrast to the translational phases of flight during which gaze direction is kept largely constant, walking flies experience continuous rotational image flow that is coupled to their stride-cycle. The consequences of these self-produced image shifts for the extraction of environmental information are still unclear. To assess the impact of stride-coupled image shifts on visual information processing, we performed electrophysiological recordings from the HSE cell, a motion sensitive wide-field neuron in the blowfly visual system. This cell has been concluded to play a key role in mediating optomotor behavior, self-motion estimation and spatial information processing. We used visual stimuli that were based on the visual input experienced by walking blowflies while approaching a black vertical bar. The response of HSE to these stimuli was dominated by periodic membrane potential fluctuations evoked by stride-coupled image shifts. Nevertheless, during the approach the cell’s response contained information about the bar and its background. The response components evoked by the bar were larger than the responses to its background, especially during the last phase of the approach. However, as revealed by targeted modifications of the visual input during walking, the extraction of distance information on the basis of HSE responses is much impaired by stride-coupled retinal image shifts. Possible mechanisms that may cope with these stride

Look Together: Analyzing Gaze Coordination with Epistemic Network Analysis

Directory of Open Access Journals (Sweden)

Sean eAndrist

2015-07-01

Full Text Available When conversing and collaborating in everyday situations, people naturally and interactively align their behaviors with each other across various communication channels, including speech, gesture, posture, and gaze. Having access to a partner's referential gaze behavior has been shown to be particularly important in achieving collaborative outcomes, but the process in which people's gaze behaviors unfold over the course of an interaction and become tightly coordinated is not well understood. In this paper, we present work to develop a deeper and more nuanced understanding of coordinated referential gaze in collaborating dyads. We recruited 13 dyads to participate in a collaborative sandwich-making task and used dual mobile eye tracking to synchronously record each participant's gaze behavior. We used a relatively new analysis technique—epistemic network analysis—to jointly model the gaze behaviors of both conversational participants. In this analysis, network nodes represent gaze targets for each participant, and edge strengths convey the likelihood of simultaneous gaze to the connected target nodes during a given time-slice. We divided collaborative task sequences into discrete phases to examine how the networks of shared gaze evolved over longer time windows. We conducted three separate analyses of the data to reveal (1 properties and patterns of how gaze coordination unfolds throughout an interaction sequence, (2 optimal time lags of gaze alignment within a dyad at different phases of the interaction, and (3 differences in gaze coordination patterns for interaction sequences that lead to breakdowns and repairs. In addition to contributing to the growing body of knowledge on the coordination of gaze behaviors in joint activities, this work has implications for the design of future technologies that engage in situated interactions with human users.

Facilitated orienting underlies fearful face-enhanced gaze cueing of spatial location

Directory of Open Access Journals (Sweden)

Joshua M. Carlson

2016-12-01

Full Text Available Faces provide a platform for non-verbal communication through emotional expression and eye gaze. Fearful facial expressions are salient indicators of potential threat within the environment, which automatically capture observers’ attention. However, the degree to which fearful facial expressions facilitate attention to others’ gaze is unresolved. Given that fearful gaze indicates the location of potential threat, it was hypothesized that fearful gaze facilitates location processing. To test this hypothesis, a gaze cueing study with fearful and neutral faces assessing target localization was conducted. The task consisted of leftward, rightward, and forward/straight gaze trials. The inclusion of forward gaze trials allowed for the isolation of orienting and disengagement components of gaze-directed attention. The results suggest that both neutral and fearful gaze modulates attention through orienting and disengagement components. Fearful gaze, however, resulted in quicker orienting than neutral gaze. Thus, fearful faces enhance gaze cueing of spatial location through facilitated orienting.

Soluble salt removal from MSWI fly ash and its stabilization for safer disposal and recovery as road basement material.

Science.gov (United States)

Colangelo, F; Cioffi, R; Montagnaro, F; Santoro, L

2012-06-01

Fly ash from municipal solid waste incinerators (MSWI) is classified as hazardous in the European Waste Catalogue. Proper stabilization processes should be required before any management option is put into practice. Due to the inorganic nature of MSWI fly ash, cementitious stabilization processes are worthy of consideration. However, the effectiveness of such processes can be severely compromised by the high content of soluble chlorides and sulphates. In this paper, a preliminary washing treatment has been optimized to remove as much as possible soluble salts by employing as little as possible water. Two different operating conditions (single-step and two-step) have been developed to this scope. Furthermore, it has been demonstrated that stabilized systems containing 20% of binder are suitable for safer disposal as well as for material recovery in the field of road basement (cement bound granular material layer). Three commercially available cements (pozzolanic, limestone and slag) have been employed as binders. Copyright © 2012 Elsevier Ltd. All rights reserved.

Judgments at Gaze Value: Gaze Cuing in Banner Advertisements, Its Effect on Attention Allocation and Product Judgments

Directory of Open Access Journals (Sweden)

Johanna Palcu

2017-06-01

Full Text Available Banner advertising is a popular means of promoting products and brands online. Although banner advertisements are often designed to be particularly attention grabbing, they frequently go unnoticed. Applying an eye-tracking procedure, the present research aimed to (a determine whether presenting human faces (static or animated in banner advertisements is an adequate tool for capturing consumers’ attention and thus overcoming the frequently observed phenomenon of banner blindness, (b to examine whether the gaze of a featured face possesses the ability to direct consumers’ attention toward specific elements (i.e., the product in an advertisement, and (c to establish whether the gaze direction of an advertised face influences consumers subsequent evaluation of the advertised product. We recorded participants’ eye gaze while they viewed a fictional online shopping page displaying banner advertisements that featured either no human face or a human face that was either static or animated and involved different gaze directions (toward or away from the advertised product. Moreover, we asked participants to subsequently evaluate a set of products, one of which was the product previously featured in the banner advertisement. Results showed that, when advertisements included a human face, participants’ attention was more attracted by and they looked longer at animated compared with static banner advertisements. Moreover, when a face gazed toward the product region, participants’ likelihood of looking at the advertised product increased regardless of whether the face was animated or not. Most important, gaze direction influenced subsequent product evaluations; that is, consumers indicated a higher intention to buy a product when it was previously presented in a banner advertisement that featured a face that gazed toward the product. The results suggest that while animation in banner advertising constitutes a salient feature that captures consumers�

Judgments at Gaze Value: Gaze Cuing in Banner Advertisements, Its Effect on Attention Allocation and Product Judgments.

Science.gov (United States)

Palcu, Johanna; Sudkamp, Jennifer; Florack, Arnd

2017-01-01

Banner advertising is a popular means of promoting products and brands online. Although banner advertisements are often designed to be particularly attention grabbing, they frequently go unnoticed. Applying an eye-tracking procedure, the present research aimed to (a) determine whether presenting human faces (static or animated) in banner advertisements is an adequate tool for capturing consumers' attention and thus overcoming the frequently observed phenomenon of banner blindness, (b) to examine whether the gaze of a featured face possesses the ability to direct consumers' attention toward specific elements (i.e., the product) in an advertisement, and (c) to establish whether the gaze direction of an advertised face influences consumers subsequent evaluation of the advertised product. We recorded participants' eye gaze while they viewed a fictional online shopping page displaying banner advertisements that featured either no human face or a human face that was either static or animated and involved different gaze directions (toward or away from the advertised product). Moreover, we asked participants to subsequently evaluate a set of products, one of which was the product previously featured in the banner advertisement. Results showed that, when advertisements included a human face, participants' attention was more attracted by and they looked longer at animated compared with static banner advertisements. Moreover, when a face gazed toward the product region, participants' likelihood of looking at the advertised product increased regardless of whether the face was animated or not. Most important, gaze direction influenced subsequent product evaluations; that is, consumers indicated a higher intention to buy a product when it was previously presented in a banner advertisement that featured a face that gazed toward the product. The results suggest that while animation in banner advertising constitutes a salient feature that captures consumers' visual attention, gaze

Synthesis of a one-part geopolymer system for soil stabilizer using fly ash and volcanic ash

Directory of Open Access Journals (Sweden)

Tigue April Anne S.

2018-01-01

Full Text Available A novel approach one-part geopolymer was employed to investigate the feasibility of enhancing the strength of in-situ soil for possible structural fill application in the construction industry. Geopolymer precursors such as fly ash and volcanic ash were utilized in this study for soil stabilization. The traditional geopolymer synthesis uses soluble alkali activators unlike in the case of ordinary Portland cement where only water is added to start the hydration process. This kind of synthesis is an impediment to geopolymer soil stabilizer commercial viability. Hence, solid alkali activators such as sodium silicate (SS, sodium hydroxide (SH, and sodium aluminate (SA were explored. The influence of amount of fly ash (15% and 25%, addition of volcanic ash (0% and 12.5%, and ratio of alkali activator SS:SH:SA (50:50:0, 33:33:33, 50:20:30 were investigated. Samples cured for 28 days were tested for unconfined compressive strength (UCS. To evaluate the durability, sample yielding highest UCS was subjected to sulfuric acid resistance test for 28 days. Analytical techniques such as X-ray fluorescence (XRF, X-ray diffraction (XRD, and scanning electron microscope/energy-dispersive X-ray spectroscopy (SEM/EDX were performed to examine the elemental composition, mineralogical properties, and microstructure of the precursors and the geopolymer stabilized soil.

Gaze perception in social anxiety and social anxiety disorder

Directory of Open Access Journals (Sweden)

Lars eSchulze

2013-12-01

Full Text Available Clinical observations suggest abnormal gaze perception to be an important indicator of social anxiety disorder (SAD. Experimental research has yet paid relatively little attention to the study of gaze perception in SAD. In this article we first discuss gaze perception in healthy human beings before reviewing self-referential and threat-related biases of gaze perception in clinical and non-clinical socially anxious samples. Relative to controls, socially anxious individuals exhibit an enhanced self-directed perception of gaze directions and demonstrate a pronounced fear of direct eye contact, though findings are less consistent regarding the avoidance of mutual gaze in SAD. Prospects for future research and clinical implications are discussed.

Wolves (Canis lupus) and Dogs (Canis familiaris) Differ in Following Human Gaze Into Distant Space But Respond Similar to Their Packmates’ Gaze

Science.gov (United States)

Werhahn, Geraldine; Virányi, Zsófia; Barrera, Gabriela; Sommese, Andrea; Range, Friederike

2017-01-01

Gaze following into distant space is defined as visual co-orientation with another individual’s head direction allowing the gaze follower to gain information on its environment. Human and nonhuman animals share this basic gaze following behavior, suggested to rely on a simple reflexive mechanism and believed to be an important prerequisite for complex forms of social cognition. Pet dogs differ from other species in that they follow only communicative human gaze clearly addressed to them. However, in an earlier experiment we showed that wolves follow human gaze into distant space. Here we set out to investigate whether domestication has affected gaze following in dogs by comparing pack-living dogs and wolves raised and kept under the same conditions. In Study 1 we found that in contrast to the wolves, these dogs did not follow minimally communicative human gaze into distant space in the same test paradigm. In the observational Study 2 we found that pack-living dogs and wolves, similarly vigilant to environmental stimuli, follow the spontaneous gaze of their conspecifics similarly often. Our findings suggest that domestication did not affect the gaze following ability of dogs itself. The results raise hypotheses about which other dog skills might have been altered through domestication that may have influenced their performance in Study 1. Because following human gaze in dogs might be influenced by special evolutionary as well as developmental adaptations to interactions with humans, we suggest that comparing dogs to other animal species might be more informative when done in intraspecific social contexts. PMID:27244538

Wolves (Canis lupus) and dogs (Canis familiaris) differ in following human gaze into distant space but respond similar to their packmates' gaze.

Science.gov (United States)

Werhahn, Geraldine; Virányi, Zsófia; Barrera, Gabriela; Sommese, Andrea; Range, Friederike

2016-08-01

Gaze following into distant space is defined as visual co-orientation with another individual's head direction allowing the gaze follower to gain information on its environment. Human and nonhuman animals share this basic gaze following behavior, suggested to rely on a simple reflexive mechanism and believed to be an important prerequisite for complex forms of social cognition. Pet dogs differ from other species in that they follow only communicative human gaze clearly addressed to them. However, in an earlier experiment we showed that wolves follow human gaze into distant space. Here we set out to investigate whether domestication has affected gaze following in dogs by comparing pack-living dogs and wolves raised and kept under the same conditions. In Study 1 we found that in contrast to the wolves, these dogs did not follow minimally communicative human gaze into distant space in the same test paradigm. In the observational Study 2 we found that pack-living dogs and wolves, similarly vigilant to environmental stimuli, follow the spontaneous gaze of their conspecifics similarly often. Our findings suggest that domestication did not affect the gaze following ability of dogs itself. The results raise hypotheses about which other dog skills might have been altered through domestication that may have influenced their performance in Study 1. Because following human gaze in dogs might be influenced by special evolutionary as well as developmental adaptations to interactions with humans, we suggest that comparing dogs to other animal species might be more informative when done in intraspecific social contexts. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Interactive wiimote gaze stabilization exercise training system for patients with vestibular hypofunction.

Science.gov (United States)

Chen, Po-Yin; Hsieh, Wan-Ling; Wei, Shun-Hwa; Kao, Chung-Lan

2012-10-09

Peripheral vestibular hypofunction is a major cause of dizziness. When complicated with postural imbalance, this condition can lead to an increased incidence of falls. In traditional clinical practice, gaze stabilization exercise is commonly used to rehabilitate patients. In this study, we established a computer-aided vestibular rehabilitation system by coupling infrared LEDs to an infrared receiver. This system enabled the subjects' head-turning actions to be quantified, and the training was performed using vestibular exercise combined with computer games and interactive video games that simulate daily life activities. Three unilateral and one bilateral vestibular hypofunction patients volunteered to participate in this study. The participants received 30 minutes of computer-aided vestibular rehabilitation training 2 days per week for 6 weeks. Pre-training and post-training assessments were completed, and a follow-up assessment was completed 1 month after the end of the training period. After 6 weeks of training, significant improvements in balance and dynamic visual acuity (DVA) were observed in the four participants. Self-reports of dizziness, anxiety and depressed mood all decreased significantly. Significant improvements in self-confidence and physical performance were also observed. The effectiveness of this training was maintained for at least 1 month after the end of the training period. Real-time monitoring of training performance can be achieved using this rehabilitation platform. Patients demonstrated a reduction in dizziness symptoms after 6 weeks of training with this short-term interactive game approach. This treatment paradigm also improved the patients' balance function. This system could provide a convenient, safe and affordable treatment option for clinical practitioners.

Design gaze simulation for people with visual disability

NARCIS (Netherlands)

Qiu, S.

2017-01-01

In face-to-face communication, eye gaze is integral to a conversation to supplement verbal language. The sighted often uses eye gaze to convey nonverbal information in social interactions, which a blind conversation partner cannot access and react. My doctoral research is to design gaze simulation

Mental state attribution and the gaze cueing effect.

Science.gov (United States)

Cole, Geoff G; Smith, Daniel T; Atkinson, Mark A

2015-05-01

Theory of mind is said to be possessed by an individual if he or she is able to impute mental states to others. Recently, some authors have demonstrated that such mental state attributions can mediate the "gaze cueing" effect, in which observation of another individual shifts an observer's attention. One question that follows from this work is whether such mental state attributions produce mandatory modulations of gaze cueing. Employing the basic gaze cueing paradigm, together with a technique commonly used to assess mental-state attribution in nonhuman animals, we manipulated whether the gazing agent could see the same thing as the participant (i.e., the target) or had this view obstructed by a physical barrier. We found robust gaze cueing effects, even when the observed agent in the display could not see the same thing as the participant. These results suggest that the attribution of "seeing" does not necessarily modulate the gaze cueing effect.

Stability region of closed-loop pilot-vehicle system for fly-by-wire aircraft with limited actuator rate

OpenAIRE

Ying-hui, Li; Liang, Qu; Hao-jun, Xu; Qi-meng, Cao

2017-01-01

The category-II PIO (Pilot Induced Oscillations) caused by actuator rate limitation of fly-by-wire airplanes will badly threaten the flight safety. The stability regions of closed-loop pilot-vehicle (CLPV) system with rate limited actuator were studied in this paper to assess stability of such CLPV system. The augmented state  variables were introduced to segregate the rate limited element from the primary  system in order to build the saturation nonlinear model of CLPV system. To get the max...

Training for eye contact modulates gaze following in dogs.

Science.gov (United States)

Wallis, Lisa J; Range, Friederike; Müller, Corsin A; Serisier, Samuel; Huber, Ludwig; Virányi, Zsófia

2015-08-01

Following human gaze in dogs and human infants can be considered a socially facilitated orientation response, which in object choice tasks is modulated by human-given ostensive cues. Despite their similarities to human infants, and extensive skills in reading human cues in foraging contexts, no evidence that dogs follow gaze into distant space has been found. We re-examined this question, and additionally whether dogs' propensity to follow gaze was affected by age and/or training to pay attention to humans. We tested a cross-sectional sample of 145 border collies aged 6 months to 14 years with different amounts of training over their lives. The dogs' gaze-following response in test and control conditions before and after training for initiating eye contact with the experimenter was compared with that of a second group of 13 border collies trained to touch a ball with their paw. Our results provide the first evidence that dogs can follow human gaze into distant space. Although we found no age effect on gaze following, the youngest and oldest age groups were more distractible, which resulted in a higher number of looks in the test and control conditions. Extensive lifelong formal training as well as short-term training for eye contact decreased dogs' tendency to follow gaze and increased their duration of gaze to the face. The reduction in gaze following after training for eye contact cannot be explained by fatigue or short-term habituation, as in the second group gaze following increased after a different training of the same length. Training for eye contact created a competing tendency to fixate the face, which prevented the dogs from following the directional cues. We conclude that following human gaze into distant space in dogs is modulated by training, which may explain why dogs perform poorly in comparison to other species in this task.

[Effect of sodium carbonate assisted hydrothermal process on heavy metals stabilization in medical waste incinerator fly ash].

Science.gov (United States)

Jin, Jian; Li, Xiao-dong; Chi, Yong; Yan, Jian-hua

2010-04-01

A sodium carbonate assisted hydrothermal process was induced to stabilize the fly ash from medical waste incinerator. The results showed that sodium carbonate assisted hydrothermal process reduced the heavy metals leachability of fly ash, and the heavy metal waste water from the process would not be a secondary pollution. The leachability of heavy metals studied in this paper were Cd 1.97 mg/L, Cr 1.56 mg/L, Cu 2.56 mg/L, Mn 17.30 mg/L, Ni 1.65 mg/L, Pb 1.56 mg/L and Zn 189.00 mg/L, and after hydrothermal process with the optimal experimental condition (Na2CO3/fly ash dosage = 5/20, reaction time = 8 h, L/S ratio = 10/1) the leachability reduced to < 0.02 mg/L for Cd, Cr, Cu, Mn, Ni, Pb, and 0.05 mg/L for Zn, according to GB 5085.3-2007. Meanwhile, the concentrations of heavy metals in effluent after hydrothermal process were less than 0.8 mg/L. The heavy metals leachability and concentration in effluent reduced with prolonged reaction time. Prolonged aging can affect the leachability of metals as solids become more crystalline, and heavy metals transferred inside of crystalline. The mechanism of heavy metal stabilization can be concluded to the co precipitation and adsorption effect of aluminosilicates formation, crystallization and aging process.

Speaker gaze increases information coupling between infant and adult brains.

Science.gov (United States)

Leong, Victoria; Byrne, Elizabeth; Clackson, Kaili; Georgieva, Stanimira; Lam, Sarah; Wass, Sam

2017-12-12

When infants and adults communicate, they exchange social signals of availability and communicative intention such as eye gaze. Previous research indicates that when communication is successful, close temporal dependencies arise between adult speakers' and listeners' neural activity. However, it is not known whether similar neural contingencies exist within adult-infant dyads. Here, we used dual-electroencephalography to assess whether direct gaze increases neural coupling between adults and infants during screen-based and live interactions. In experiment 1 ( n = 17), infants viewed videos of an adult who was singing nursery rhymes with ( i ) direct gaze (looking forward), ( ii ) indirect gaze (head and eyes averted by 20°), or ( iii ) direct-oblique gaze (head averted but eyes orientated forward). In experiment 2 ( n = 19), infants viewed the same adult in a live context, singing with direct or indirect gaze. Gaze-related changes in adult-infant neural network connectivity were measured using partial directed coherence. Across both experiments, the adult had a significant (Granger) causal influence on infants' neural activity, which was stronger during direct and direct-oblique gaze relative to indirect gaze. During live interactions, infants also influenced the adult more during direct than indirect gaze. Further, infants vocalized more frequently during live direct gaze, and individual infants who vocalized longer also elicited stronger synchronization from the adult. These results demonstrate that direct gaze strengthens bidirectional adult-infant neural connectivity during communication. Thus, ostensive social signals could act to bring brains into mutual temporal alignment, creating a joint-networked state that is structured to facilitate information transfer during early communication and learning. Copyright © 2017 the Author(s). Published by PNAS.

Embodied social robots trigger gaze following in real-time

OpenAIRE

Wiese, Eva; Weis, Patrick; Lofaro, Daniel

2018-01-01

In human-human interaction, we use information from gestures, facial expressions and gaze direction to make inferences about what interaction partners think, feel or intend to do next. Observing changes in gaze direction triggers shifts of attention to gazed-at locations and helps establish shared attention between gazer and observer - a prerequisite for more complex social skills like mentalizing, action understanding and joint action. The ability to follow others’ gaze develops early in lif...

Adaptive gaze control for object detection

NARCIS (Netherlands)

De Croon, G.C.H.E.; Postma, E.O.; Van den Herik, H.J.

2011-01-01

We propose a novel gaze-control model for detecting objects in images. The model, named act-detect, uses the information from local image samples in order to shift its gaze towards object locations. The model constitutes two main contributions. The first contribution is that the model’s setup makes

Attention to gaze and emotion in schizophrenia.

Science.gov (United States)

Schwartz, Barbara L; Vaidya, Chandan J; Howard, James H; Deutsch, Stephen I

2010-11-01

Individuals with schizophrenia have difficulty interpreting social and emotional cues such as facial expression, gaze direction, body position, and voice intonation. Nonverbal cues are powerful social signals but are often processed implicitly, outside the focus of attention. The aim of this research was to assess implicit processing of social cues in individuals with schizophrenia. Patients with schizophrenia or schizoaffective disorder and matched controls performed a primary task of word classification with social cues in the background. Participants were asked to classify target words (LEFT/RIGHT) by pressing a key that corresponded to the word, in the context of facial expressions with eye gaze averted to the left or right. Although facial expression and gaze direction were irrelevant to the task, these facial cues influenced word classification performance. Participants were slower to classify target words (e.g., LEFT) that were incongruent to gaze direction (e.g., eyes averted to the right) compared to target words (e.g., LEFT) that were congruent to gaze direction (e.g., eyes averted to the left), but this only occurred for expressions of fear. This pattern did not differ for patients and controls. The results showed that threat-related signals capture the attention of individuals with schizophrenia. These data suggest that implicit processing of eye gaze and fearful expressions is intact in schizophrenia. (c) 2010 APA, all rights reserved

A comparison of facial color pattern and gazing behavior in canid species suggests gaze communication in gray wolves (Canis lupus.

Directory of Open Access Journals (Sweden)

Sayoko Ueda

Full Text Available As facial color pattern around the eyes has been suggested to serve various adaptive functions related to the gaze signal, we compared the patterns among 25 canid species, focusing on the gaze signal, to estimate the function of facial color pattern in these species. The facial color patterns of the studied species could be categorized into the following three types based on contrast indices relating to the gaze signal: A-type (both pupil position in the eye outline and eye position in the face are clear, B-type (only the eye position is clear, and C-type (both the pupil and eye position are unclear. A-type faces with light-colored irises were observed in most studied species of the wolf-like clade and some of the red fox-like clade. A-type faces tended to be observed in species living in family groups all year-round, whereas B-type faces tended to be seen in solo/pair-living species. The duration of gazing behavior during which the facial gaze-signal is displayed to the other individual was longest in gray wolves with typical A-type faces, of intermediate length in fennec foxes with typical B-type faces, and shortest in bush dogs with typical C-type faces. These results suggest that the facial color pattern of canid species is related to their gaze communication and that canids with A-type faces, especially gray wolves, use the gaze signal in conspecific communication.

Interactive wiimote gaze stabilization exercise training system for patients with vestibular hypofunction

Directory of Open Access Journals (Sweden)

Chen Po-Yin

2012-10-01

Full Text Available Abstract Background Peripheral vestibular hypofunction is a major cause of dizziness. When complicated with postural imbalance, this condition can lead to an increased incidence of falls. In traditional clinical practice, gaze stabilization exercise is commonly used to rehabilitate patients. In this study, we established a computer-aided vestibular rehabilitation system by coupling infrared LEDs to an infrared receiver. This system enabled the subjects’ head-turning actions to be quantified, and the training was performed using vestibular exercise combined with computer games and interactive video games that simulate daily life activities. Methods Three unilateral and one bilateral vestibular hypofunction patients volunteered to participate in this study. The participants received 30 minutes of computer-aided vestibular rehabilitation training 2 days per week for 6 weeks. Pre-training and post-training assessments were completed, and a follow-up assessment was completed 1 month after the end of the training period. Results After 6 weeks of training, significant improvements in balance and dynamic visual acuity (DVA were observed in the four participants. Self-reports of dizziness, anxiety and depressed mood all decreased significantly. Significant improvements in self-confidence and physical performance were also observed. The effectiveness of this training was maintained for at least 1 month after the end of the training period. Conclusion Real-time monitoring of training performance can be achieved using this rehabilitation platform. Patients demonstrated a reduction in dizziness symptoms after 6 weeks of training with this short-term interactive game approach. This treatment paradigm also improved the patients’ balance function. This system could provide a convenient, safe and affordable treatment option for clinical practitioners.

Contribution of the maculo-ocular reflex to gaze stability in the rabbit.

Science.gov (United States)

Pettorossi, V E; Errico, P; Santarelli, R M

1991-01-01

The contribution of the maculo-ocular reflex to gaze stability was studied in 10 pigmented rabbits by rolling the animals at various angles of sagittal inclination of the rotation and/or longitudinal animal axes. At low frequencies (0.005-0.01 Hz) of sinusoidal stimulation the vestibulo-ocular reflex (VOR) was due to macular activation, while at intermediate and high frequencies it was mainly due to ampullar activation. The following results were obtained: 1) maculo-ocular reflex gain decreased as a function of the cosine of the angle between the rotation axis and the earth's horizontal plane. No change in gain was observed when longitudinal animal axis alone was inclined. 2) At 0 degrees of rotation axis and with the animal's longitudinal axis inclination also set at 0 degrees, the maculo-ocular reflex was oriented about 20 degrees forward and upward with respect to the earth's vertical axis. This orientation remained constant with sagittal inclinations of the rotation and/or longitudinal animal axes ranging from approximately 5 degrees upward to 30 degrees downward. When the longitudinal animal axis was inclined beyond these limits, the eye trajectory tended to follow the axis inclination. In the upside down position, the maculo-ocular reflex was anticompensatory, oblique and fixed with respect to orbital coordinates. 3) Ampullo-ocular reflex gain did not change with inclinations of the rotation and/or longitudinal animal axes. The ocular responses were consistently oriented to the stimulus plane. At intermediate frequencies the eye movement trajectory was elliptic because of directional differences between the ampullo- and maculo-ocular reflexes.(ABSTRACT TRUNCATED AT 250 WORDS)

Reading the mind from eye gaze.

NARCIS (Netherlands)

Christoffels, I.; Young, A.W.; Owen, A.M.; Scott, S.K.; Keane, J.; Lawrence, A.D.

2002-01-01

S. Baron-Cohen (1997) has suggested that the interpretation of gaze plays an important role in a normal functioning theory of mind (ToM) system. Consistent with this suggestion, functional imaging research has shown that both ToM tasks and eye gaze processing engage a similar region of the posterior

Optimization of soil stabilization with class C fly ash.

Science.gov (United States)

1987-01-01

Previous Iowa DOT sponsored research has shown that some Class : C fly ashes are cementitious (because calcium is combined as calcium : aluminates) while other Class C ashes containing similar amounts of : elemental calcium are not (1). Fly ashes fro...

Latvijas Gaze buyback likely to flop

Index Scriptorium Estoniae

2003-01-01

Veerandi Läti gaasifirma Latvijas Gaze omanik Itera kavatseb lähiajal lõpule viia üheksa protsendi Läti firma aktsiate müügi ettevõttele Gazprom. Gazprom'i kontrolli all on praegu 25 protsenti, Ruhrgas'il 28,66 ning E.ON Energie AG-l 18,06 protsenti Latvijas Gaze aktsiatest

Emotion Unchained: Facial Expression Modulates Gaze Cueing under Cognitive Load.

Science.gov (United States)

Pecchinenda, Anna; Petrucci, Manuel

2016-01-01

Direction of eye gaze cues spatial attention, and typically this cueing effect is not modulated by the expression of a face unless top-down processes are explicitly or implicitly involved. To investigate the role of cognitive control on gaze cueing by emotional faces, participants performed a gaze cueing task with happy, angry, or neutral faces under high (i.e., counting backward by 7) or low cognitive load (i.e., counting forward by 2). Results show that high cognitive load enhances gaze cueing effects for angry facial expressions. In addition, cognitive load reduces gaze cueing for neutral faces, whereas happy facial expressions and gaze affected object preferences regardless of load. This evidence clearly indicates a differential role of cognitive control in processing gaze direction and facial expression, suggesting that under typical conditions, when we shift attention based on social cues from another person, cognitive control processes are used to reduce interference from emotional information.

Gliding and Saccadic Gaze Gesture Recognition in Real Time

DEFF Research Database (Denmark)

Rozado, David; San Agustin, Javier; Rodriguez, Francisco

2012-01-01

, and their corresponding real-time recognition algorithms, Hierarchical Temporal Memory networks and the Needleman-Wunsch algorithm for sequence alignment. Our results show how a specific combination of gaze gesture modality, namely saccadic gaze gestures, and recognition algorithm, Needleman-Wunsch, allows for reliable...... usage of intentional gaze gestures to interact with a computer with accuracy rates of up to 98% and acceptable completion speed. Furthermore, the gesture recognition engine does not interfere with otherwise standard human-machine gaze interaction generating therefore, very low false positive rates...

Mobile gaze input system for pervasive interaction

DEFF Research Database (Denmark)

2017-01-01

feedback to the user in response to the received command input. The unit provides feedback to the user on how to position the mobile unit in front of his eyes. The gaze tracking unit interacts with one or more controlled devices via wireless or wired communications. Example devices include a lock......, a thermostat, a light or a TV. The connection between the gaze tracking unit may be temporary or longer-lasting. The gaze tracking unit may detect features of the eye that provide information about the identity of the user....

The Use of Dynamic Visual Acuity as a Functional Test of Gaze Stabilization Following Space Flight

Science.gov (United States)

Peters, B. T.; Mulavara, A. P.; Brady, R.; Miller, C. A.; Richards, J. T.; Warren, L. E.; Cohen, H. S.; Bloomberg, J. J.

2006-01-01

performance of some subjects nicely parallels the stereotypical recovery curve observed in the group mean data. Others show dramatic changes in DVA from one test day to another. These changes may be indicative of a re-adaptation process that is not characterized by a steady improvement with the passage of time, but is instead a dynamic search for appropriate coordinative strategy to achieve the desired gaze stabilization goal. Ground-based data have been collected in our lab using DVA with one of the goals being to improve the DVA test itself. In one of these studies, the DVA test was repeated using a visual target viewing distance of 0.5 meters. While walking, the relative contributions of the otoliths and semi-circular canals that are required to stabilize gaze are affected by visual target viewing distance. It may be possible to exploit this using the current treadmill DVA test to differentially assess changes in these vestibular subsystems. The postflight DVA evaluations currently used have been augmented to include the near target version of the test. Preliminary results from these assessments, as well as the results from the ground-based tests will also be reported. DVA provides a direct measure of a subject's ability to see clearly in the presence of self-motion. The use of the current tests for providing a functionally relevant metric is evident. However, it is possible to expand the scope of DVA testing to include scenarios other than walking. A facility for measuring DVA in the presence of passive movements is being created. Using a mechanized platform to provide the perturbation, it should be possible to simulate aircraft and automobile vibration profiles. Used in conjunction with the far and near visual displays this facility should be able to assess a subject s ability to clearly see distant objects as well as those that appear on the dashboard or instrument control panel during functionally relevant situations.

Face age modulates gaze following in young adults.

Science.gov (United States)

Ciardo, Francesca; Marino, Barbara F M; Actis-Grosso, Rossana; Rossetti, Angela; Ricciardelli, Paola

2014-04-22

Gaze-following behaviour is considered crucial for social interactions which are influenced by social similarity. We investigated whether the degree of similarity, as indicated by the perceived age of another person, can modulate gaze following. Participants of three different age-groups (18-25; 35-45; over 65) performed an eye movement (a saccade) towards an instructed target while ignoring the gaze-shift of distracters of different age-ranges (6-10; 18-25; 35-45; over 70). The results show that gaze following was modulated by the distracter face age only for young adults. Particularly, the over 70 year-old distracters exerted the least interference effect. The distracters of a similar age-range as the young adults (18-25; 35-45) had the most effect, indicating a blurred own-age bias (OAB) only for the young age group. These findings suggest that face age can modulate gaze following, but this modulation could be due to factors other than just OAB (e.g., familiarity).

Gaze Bias in Preference Judgments by Younger and Older Adults

Directory of Open Access Journals (Sweden)

Toshiki Saito

2017-08-01

Full Text Available Individuals’ gaze behavior reflects the choice they will ultimately make. For example, people confronting a choice among multiple stimuli tend to look longer at stimuli that are subsequently chosen than at other stimuli. This tendency, called the gaze bias effect, is a key aspect of visual decision-making. Nevertheless, no study has examined the generality of the gaze bias effect in older adults. Here, we used a two-alternative forced-choice task (2AFC to compare the gaze behavior reflective of different stages of decision processes demonstrated by younger and older adults. Participants who had viewed two faces were instructed to choose the one that they liked/disliked or the one that they judged to be more/less similar to their own face. Their eye movements were tracked while they chose. The results show that the gaze bias effect occurred during the remaining time in both age groups irrespective of the decision type. However, no gaze bias effect was observed for the preference judgment during the first dwell time. Our study demonstrated that the gaze bias during the remaining time occurred regardless of decision-making task and age. Further study using diverse participants, such as clinic patients or infants, may help to generalize the gaze bias effect and to elucidate the mechanisms underlying the gaze bias.

Direct Speaker Gaze Promotes Trust in Truth-Ambiguous Statements.

Science.gov (United States)

Kreysa, Helene; Kessler, Luise; Schweinberger, Stefan R

2016-01-01

A speaker's gaze behaviour can provide perceivers with a multitude of cues which are relevant for communication, thus constituting an important non-verbal interaction channel. The present study investigated whether direct eye gaze of a speaker affects the likelihood of listeners believing truth-ambiguous statements. Participants were presented with videos in which a speaker produced such statements with either direct or averted gaze. The statements were selected through a rating study to ensure that participants were unlikely to know a-priori whether they were true or not (e.g., "sniffer dogs cannot smell the difference between identical twins"). Participants indicated in a forced-choice task whether or not they believed each statement. We found that participants were more likely to believe statements by a speaker looking at them directly, compared to a speaker with averted gaze. Moreover, when participants disagreed with a statement, they were slower to do so when the statement was uttered with direct (compared to averted) gaze, suggesting that the process of rejecting a statement as untrue may be inhibited when that statement is accompanied by direct gaze.

Animating Flames: Recovering Fire-Gazing as a Moving-Image Technology

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Anne Sullivan

2017-12-01

Full Text Available In nineteenth-century England, the industrialization of heat and light rendered fire-gazing increasingly obsolete. Fire-gazing is a form of flame-based reverie that typically involves a solitary viewer who perceives animated, moving images dissolving into and out of view in a wood or coal fire. When fire-gazing, the viewer may perceive arbitrary pictures, fantastic landscapes, or more familiar forms, such as the faces of friends and family. This article recovers fire-gazing as an early and more intimate animation technology by examining remediations of fire-gazing in print. After reviewing why an analysis of fire-gazing requires a joint literary and media history approach, I build from Michael Faraday’s mid-nineteenth-century theorization of flame as a moving image to argue that fire-gazing must be included in the history of animation technologies. I then demonstrate the uneasy connections that form between automatism, mechanical reproduction, and creativity in Leigh Hunt’s description of fire-gazing in his 1811 essay ‘A Day by the Fire’. The tension between conscious and unconscious modes of production culminates in a discussion of fireside scenes of (reanimation in Charles Dickens’s 'Our Mutual Friend' (1864–65, including those featuring one of his more famous fire-gazers, Lizzie Hexam. The article concludes with a brief discussion of the 1908 silent film 'Fireside Reminiscences' as an example of the continued remediations of fire-gazing beyond the nineteenth century.

Just one look: Direct gaze briefly disrupts visual working memory.

Science.gov (United States)

Wang, J Jessica; Apperly, Ian A

2017-04-01

Direct gaze is a salient social cue that affords rapid detection. A body of research suggests that direct gaze enhances performance on memory tasks (e.g., Hood, Macrae, Cole-Davies, & Dias, Developmental Science, 1, 67-71, 2003). Nonetheless, other studies highlight the disruptive effect direct gaze has on concurrent cognitive processes (e.g., Conty, Gimmig, Belletier, George, & Huguet, Cognition, 115(1), 133-139, 2010). This discrepancy raises questions about the effects direct gaze may have on concurrent memory tasks. We addressed this topic by employing a change detection paradigm, where participants retained information about the color of small sets of agents. Experiment 1 revealed that, despite the irrelevance of the agents' eye gaze to the memory task at hand, participants were worse at detecting changes when the agents looked directly at them compared to when the agents looked away. Experiment 2 showed that the disruptive effect was relatively short-lived. Prolonged presentation of direct gaze led to recovery from the initial disruption, rather than a sustained disruption on change detection performance. The present study provides the first evidence that direct gaze impairs visual working memory with a rapidly-developing yet short-lived effect even when there is no need to attend to agents' gaze.

Face Age and Eye Gaze Influence Older Adults' Emotion Recognition.

Science.gov (United States)

Campbell, Anna; Murray, Janice E; Atkinson, Lianne; Ruffman, Ted

2017-07-01

Eye gaze has been shown to influence emotion recognition. In addition, older adults (over 65 years) are not as influenced by gaze direction cues as young adults (18-30 years). Nevertheless, these differences might stem from the use of young to middle-aged faces in emotion recognition research because older adults have an attention bias toward old-age faces. Therefore, using older face stimuli might allow older adults to process gaze direction cues to influence emotion recognition. To investigate this idea, young and older adults completed an emotion recognition task with young and older face stimuli displaying direct and averted gaze, assessing labeling accuracy for angry, disgusted, fearful, happy, and sad faces. Direct gaze rather than averted gaze improved young adults' recognition of emotions in young and older faces, but for older adults this was true only for older faces. The current study highlights the impact of stimulus face age and gaze direction on emotion recognition in young and older adults. The use of young face stimuli with direct gaze in most research might contribute to age-related emotion recognition differences. © The Author 2015. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Solidification/stabilization of ASR fly ash using Thiomer material: Optimization of compressive strength and heavy metals leaching.

Science.gov (United States)

Baek, Jin Woong; Choi, Angelo Earvin Sy; Park, Hung Suck

2017-12-01

Optimization studies of a novel and eco-friendly construction material, Thiomer, was investigated in the solidification/stabilization of automobile shredded residue (ASR) fly ash. A D-optimal mixture design was used to evaluate and optimize maximum compressive strength and heavy metals leaching by varying Thiomer (20-40wt%), ASR fly ash (30-50wt%) and sand (20-40wt%). The analysis of variance was utilized to determine the level of significance of each process parameters and interactions. The microstructure of the solidified materials was taken from a field emission-scanning electron microscopy and energy dispersive X-ray spectroscopy that confirmed successful Thiomer solidified ASR fly ash due to reduced pores and gaps in comparison with an untreated ASR fly ash. The X-ray diffraction detected the enclosed materials on the ASR fly ash primarily contained sulfur associated crystalline complexes. Results indicated the optimal conditions of 30wt% Thiomer, 30wt% ASR fly ash and 40wt% sand reached a compressive strength of 54.9MPa. For the optimum results in heavy metals leaching, 0.0078mg/LPb, 0.0260mg/L Cr, 0.0007mg/LCd, 0.0020mg/L Cu, 0.1027mg/L Fe, 0.0046mg/L Ni and 0.0920mg/L Zn were leached out, being environmentally safe due to being substantially lower than the Korean standard leaching requirements. The results also showed that Thiomer has superiority over the commonly used Portland cement asa binding material which confirmed its potential usage as an innovative approach to simultaneously synthesize durable concrete and satisfactorily pass strict environmental regulations by heavy metals leaching. Copyright © 2017 Elsevier Ltd. All rights reserved.

Visual Foraging With Fingers and Eye Gaze

Directory of Open Access Journals (Sweden)

Ómar I. Jóhannesson

2016-03-01

Full Text Available A popular model of the function of selective visual attention involves search where a single target is to be found among distractors. For many scenarios, a more realistic model involves search for multiple targets of various types, since natural tasks typically do not involve a single target. Here we present results from a novel multiple-target foraging paradigm. We compare finger foraging where observers cancel a set of predesignated targets by tapping them, to gaze foraging where observers cancel items by fixating them for 100 ms. During finger foraging, for most observers, there was a large difference between foraging based on a single feature, where observers switch easily between target types, and foraging based on a conjunction of features where observers tended to stick to one target type. The pattern was notably different during gaze foraging where these condition differences were smaller. Two conclusions follow: (a The fact that a sizeable number of observers (in particular during gaze foraging had little trouble switching between different target types raises challenges for many prominent theoretical accounts of visual attention and working memory. (b While caveats must be noted for the comparison of gaze and finger foraging, the results suggest that selection mechanisms for gaze and pointing have different operational constraints.

Steel passive state stability in activated fly ash mortars

Directory of Open Access Journals (Sweden)

Fernández-Jiménez, A.

2010-12-01

Full Text Available The present study explores the behaviour of structural steel embedded in Portland cement (OPC mortars and NaOH- and NaOH-waterglass-activated fly ash, in the presence and absence of 2 % Cl- (CaCl2. Variations were determined in the corrosion potential (Ecorr, linear polarization resistance (Rp and corrosion current density (icorr under different environmental conditions (90 days at 95 % relative humidity (RH, 30 days at ≈ 30 % RH, 760 days at ≈ 95 % RH. In the absence of Cl-, fly ash mortars were able to passivate steel reinforcement, although the stability of the passive state in changing environmental conditions was found to depend heavily on the activating solution used. Steel corrosion in the presence of 2 % Cl- was observed to be similar to the corrosion reported for the material in OPC mortars.

En el presente trabajo se estudia el comportamiento del acero estructural embebido en morteros de cemento Pórtland (OPC y de cenizas volantes activadas con NaOH y una mezcla de NaOH y waterglass, en ausencia y en presencia de un 2% de Cl- (CaCl2. Se determino la evolución del potencial de corrosión (Ecorr, la resistencia de polarización lineal (Rp y la intensidad de corrosión (icorr, variando las condiciones ambientales (90 días al 95% de humedad relativa (HR-30 días a ≈ 30% HR- 760 días a ≈ 95% HR. En ausencia de Cl- los morteros de cenizas volantes activadas pueden pasivar los refuerzos de acero, si bien la estabilidad del estado pasivo ante cambios en las condiciones ambientales parece mostrar una fuerte dependencia de la solución activadora empleada. En presencia de un 2% de Cl- los aceros se corroen mostrando en comportamiento similar al observado en morteros en base OPC.

Use of coal fly ash and other waste products in soil stabilization and road construction-including non-destructive testing of roadways.

Science.gov (United States)

2012-02-01

An extensive laboratory testing program was performed on subgrade soils stabilized using fly ash and lime kiln dust. The laboratory : program included measurements of: compaction curves, small strain elastic moduli, resilient modulus (Mr), Briaud Com...

Use of coal fly ash and other waste products in soil stabilization and road construction including non-destructive testing of roadways.

Science.gov (United States)

2012-06-01

An extensive laboratory testing program was performed on subgrade soils stabilized using fly ash and : lime kiln dust. The laboratory program included measurements of: compaction curves, small strain elastic moduli, : resilient modulus (Mr), Briaud C...

Predictive Gaze Cues and Personality Judgments: Should Eye Trust You?

OpenAIRE

Bayliss, Andrew P.; Tipper, Steven P.

2006-01-01

Although following another person's gaze is essential in fluent social interactions, the reflexive nature of this gaze-cuing effect means that gaze can be used to deceive. In a gaze-cuing procedure, participants were presented with several faces that looked to the left or right. Some faces always looked to the target (predictive-valid), some never looked to the target (predictive-invalid), and others looked toward and away from the target in equal proportions (nonpredictive). The standard gaz...

Culture and Listeners' Gaze Responses to Stuttering

Science.gov (United States)

Zhang, Jianliang; Kalinowski, Joseph

2012-01-01

Background: It is frequently observed that listeners demonstrate gaze aversion to stuttering. This response may have profound social/communicative implications for both fluent and stuttering individuals. However, there is a lack of empirical examination of listeners' eye gaze responses to stuttering, and it is unclear whether cultural background…

Proximity and Gaze Influences Facial Temperature: A Thermal Infrared Imaging Study.

Directory of Open Access Journals (Sweden)

Stephanos eIoannou

2014-08-01

Full Text Available Direct gaze and interpersonal proximity are known to lead to changes in psycho-physiology, behaviour and brain function. We know little, however, about subtler facial reactions such as rise and fall in temperature, which may be sensitive to contextual effects and functional in social interactions. Using thermal infrared imaging cameras 18 female adult participants were filmed at two interpersonal distances (intimate and social and two gaze conditions (averted and direct. The order of variation in distance was counterbalanced: half the participants experienced a female experimenter’s gaze at the social distance first before the intimate distance (a socially ‘normal’ order and half experienced the intimate distance first and then the social distance (an odd social order. At both distances averted gaze always preceded direct gaze. We found strong correlations in thermal changes between six areas of the face (forehead, chin, cheeks, nose, maxilliary and periorbital regions for all experimental conditions and developed a composite measure of thermal shifts for all analyses. Interpersonal proximity led to a thermal rise, but only in the ‘normal’ social order. Direct gaze, compared to averted gaze, led to a thermal increase at both distances with a stronger effect at intimate distance, in both orders of distance variation. Participants reported direct gaze as more intrusive than averted gaze, especially at the intimate distance. These results demonstrate the powerful effects of another person’s gaze on psycho-physiological responses, even at a distance and independent of context.

Direct Speaker Gaze Promotes Trust in Truth-Ambiguous Statements.

Directory of Open Access Journals (Sweden)

Helene Kreysa

Full Text Available A speaker's gaze behaviour can provide perceivers with a multitude of cues which are relevant for communication, thus constituting an important non-verbal interaction channel. The present study investigated whether direct eye gaze of a speaker affects the likelihood of listeners believing truth-ambiguous statements. Participants were presented with videos in which a speaker produced such statements with either direct or averted gaze. The statements were selected through a rating study to ensure that participants were unlikely to know a-priori whether they were true or not (e.g., "sniffer dogs cannot smell the difference between identical twins". Participants indicated in a forced-choice task whether or not they believed each statement. We found that participants were more likely to believe statements by a speaker looking at them directly, compared to a speaker with averted gaze. Moreover, when participants disagreed with a statement, they were slower to do so when the statement was uttered with direct (compared to averted gaze, suggesting that the process of rejecting a statement as untrue may be inhibited when that statement is accompanied by direct gaze.

Fly-ash and Green liquor as binder in gravel road stabilization. Pilot study at Iggesund; Flygaska-Groenlutslamstabiliserad skogsbilvaeg. Fallstudie Iggesund

Energy Technology Data Exchange (ETDEWEB)

Macsik, Josef; Erlandsson, Aasa; Wexell, Bengt-Arne

2009-03-15

The quality of gravel roads is of importance for public and the forestry industry. Frost damages lead to the closure of roads due to reduced bearing capacity, settlements and tracks made by wheel. Lately these frost damages have worsened due to milder winter temperatures. The need to improve the quality of these roads and to minimize the periods when the roads are closed is ever increasing. Several Swedish and Finnish projects have shown that rest materials from the paper industry can improve bearing capacity of roads. Both green liquor and fly ash was used successfully in an earlier project as pelletized mineral nutrient in forest soil. In this project fly ash and green liquor from Iggesund Paperboard was used as a binder during stabilization of a gravel road. The aim was to improve bearing capacity of a gravel road, mainly during the thawing period. The target group of the project was local road associations, forestry industry, which have a need to improve road quality, the paper industry which produce suitable rest materials and local environmental agencies. During an initial laboratory investigation proper binder recipe, based on fly ash, green liquor and cement was chosen. The laboratory investigation and earlier studies indicate in order to increase resistance to frost damage cement should be included in the binder. The aim was to stabilize ballast and improve the stabilized road materials shear strength, frost susceptibility. Total elemental content and Leachability was also investigated. Based on the results the local environmental agency was notified. During spring of 2008 two road sections, about 2 km was stabilized. The stabilized road was investigated during autumn 2008 regarding bearing capacity and environmental impact. The stabilization of the road section was estimated to cause minor impact on the recipient. The local environmental agency approved the stabilization of the road section, however increased the follow up effort with more analyses

Look together : Using gaze for assisting co-located collaborative search

NARCIS (Netherlands)

Zhang, Y.; Pfeuffer, Ken; Chong, Ming Ki; Alexander, Jason; Bulling, Andreas; Gellersen, Hans

2017-01-01

Gaze information provides indication of users focus which complements remote collaboration tasks, as distant users can see their partner’s focus. In this paper, we apply gaze for co-located collaboration, where users’ gaze locations are presented on the same display, to help collaboration between

Orienting of attention via observed eye gaze is head-centred.

Science.gov (United States)

Bayliss, Andrew P; di Pellegrino, Giuseppe; Tipper, Steven P

2004-11-01

Observing averted eye gaze results in the automatic allocation of attention to the gazed-at location. The role of the orientation of the face that produces the gaze cue was investigated. The eyes in the face could look left or right in a head-centred frame, but the face itself could be oriented 90 degrees clockwise or anticlockwise such that the eyes were gazing up or down. Significant cueing effects to targets presented to the left or right of the screen were found in these head orientation conditions. This suggests that attention was directed to the side to which the eyes would have been looking towards, had the face been presented upright. This finding provides evidence that head orientation can affect gaze following, even when the head orientation alone is not a social cue. It also shows that the mechanism responsible for the allocation of attention following a gaze cue can be influenced by intrinsic object-based (i.e. head-centred) properties of the task-irrelevant cue.

Face age modulates gaze following in young adults

OpenAIRE

Francesca Ciardo; Barbara F. M. Marino; Rossana Actis-Grosso; Angela Rossetti; Paola Ricciardelli

2014-01-01

Gaze-following behaviour is considered crucial for social interactions which are influenced by social similarity. We investigated whether the degree of similarity, as indicated by the perceived age of another person, can modulate gaze following. Participants of three different age-groups (18–25; 35–45; over 65) performed an eye movement (a saccade) towards an instructed target while ignoring the gaze-shift of distracters of different age-ranges (6–10; 18–25; 35–45; over 70). The results show ...

FliO Regulation of FliP in the Formation of the Salmonella enterica Flagellum

Science.gov (United States)

Barker, Clive S.; Meshcheryakova, Irina V.; Kostyukova, Alla S.; Samatey, Fadel A.

2010-01-01

The type III secretion system of the Salmonella flagellum consists of 6 integral membrane proteins: FlhA, FlhB, FliO, FliP, FliQ, and FliR. However, in some other type III secretion systems, a homologue of FliO is apparently absent, suggesting it has a specialized role. Deleting the fliO gene from the chromosome of a motile strain of Salmonella resulted in a drastic decrease of motility. Incubation of the ΔfliO mutant strain in motility agar, gave rise to pseudorevertants containing extragenic bypass mutations in FliP at positions R143H or F190L. Using membrane topology prediction programs, and alkaline phosphatase or GFPuv chimeric protein fusions into the FliO protein, we demonstrated that FliO is bitopic with its N-terminus in the periplasm and C-terminus in the cytoplasm. Truncation analysis of FliO demonstrated that overexpression of FliO43–125 or FliO1–95 was able to rescue motility of the ΔfliO mutant. Further, residue leucine 91 in the cytoplasmic domain was identified to be important for function. Based on secondary structure prediction, the cytoplasmic domain, FliO43–125, should contain beta-structure and alpha-helices. FliO43–125-Ala was purified and studied using circular dichroism spectroscopy; however, this domain was disordered, and its structure was a mixture of beta-sheet and random coil. Coexpression of full-length FliO with FliP increased expression levels of FliP, but coexpression with the cytoplasmic domain of FliO did not enhance FliP expression levels. Overexpression of the cytoplasmic domain of FliO further rescued motility of strains deleted for the fliO gene expressing bypass mutations in FliP. These results suggest FliO maintains FliP stability through transmembrane domain interaction. The results also demonstrate that the cytoplasmic domain of FliO has functionality, and it presumably becomes structured while interacting with its binding partners. PMID:20941389

FliO regulation of FliP in the formation of the Salmonella enterica flagellum.

Directory of Open Access Journals (Sweden)

Clive S Barker

2010-09-01

Full Text Available The type III secretion system of the Salmonella flagellum consists of 6 integral membrane proteins: FlhA, FlhB, FliO, FliP, FliQ, and FliR. However, in some other type III secretion systems, a homologue of FliO is apparently absent, suggesting it has a specialized role. Deleting the fliO gene from the chromosome of a motile strain of Salmonella resulted in a drastic decrease of motility. Incubation of the ΔfliO mutant strain in motility agar, gave rise to pseudorevertants containing extragenic bypass mutations in FliP at positions R143H or F190L. Using membrane topology prediction programs, and alkaline phosphatase or GFPuv chimeric protein fusions into the FliO protein, we demonstrated that FliO is bitopic with its N-terminus in the periplasm and C-terminus in the cytoplasm. Truncation analysis of FliO demonstrated that overexpression of FliO₄₃-₁₂₅ or FliO₁-₉₅ was able to rescue motility of the ΔfliO mutant. Further, residue leucine 91 in the cytoplasmic domain was identified to be important for function. Based on secondary structure prediction, the cytoplasmic domain, FliO₄₃-₁₂₅, should contain beta-structure and alpha-helices. FliO₄₃-₁₂₅-Ala was purified and studied using circular dichroism spectroscopy; however, this domain was disordered, and its structure was a mixture of beta-sheet and random coil. Coexpression of full-length FliO with FliP increased expression levels of FliP, but coexpression with the cytoplasmic domain of FliO did not enhance FliP expression levels. Overexpression of the cytoplasmic domain of FliO further rescued motility of strains deleted for the fliO gene expressing bypass mutations in FliP. These results suggest FliO maintains FliP stability through transmembrane domain interaction. The results also demonstrate that the cytoplasmic domain of FliO has functionality, and it presumably becomes structured while interacting with its binding partners.

Evidence for a link between changes to gaze behaviour and risk of falling in older adults during adaptive locomotion.

Science.gov (United States)

Chapman, G J; Hollands, M A

2006-11-01

There is increasing evidence that gaze stabilization with respect to footfall targets plays a crucial role in the control of visually guided stepping and that there are significant changes to gaze behaviour as we age. However, past research has not measured if age-related changes in gaze behaviour are associated with changes to stepping performance. This paper aims to identify differences in gaze behaviour between young (n=8) adults, older adults determined to be at a low-risk of falling (low-risk, n=4) and older adults prone to falling (high-risk, n=4) performing an adaptive locomotor task and attempts to relate observed differences in gaze behaviour to decline in stepping performance. Participants walked at a self-selected pace along a 9m pathway stepping into two footfall target locations en route. Gaze behaviour and lower limb kinematics were recorded using an ASL 500 gaze tracker interfaced with a Vicon motion analysis system. Results showed that older adults looked significantly sooner to targets, and fixated the targets for longer, than younger adults. There were also significant differences in these measures between high and low-risk older adults. On average, high-risk older adults looked away from targets significantly sooner and demonstrated less accurate and more variable foot placements than younger adults and low-risk older adults. These findings suggest that, as we age, we need more time to plan precise stepping movements and clearly demonstrate that there are differences between low-risk and high-risk older adults in both where and when they look at future stepping targets and the precision with which they subsequently step. We propose that high-risk older adults may prioritize the planning of future actions over the accurate execution of ongoing movements and that adoption of this strategy may contribute to an increased likelihood of falls. Copyright 2005 Elsevier B.V.

Soil stabilization 1982

Science.gov (United States)

Barenberg, E. J.; Thompson, M. R.; Tayabji, S. D.; Nussbaum, P. J.; Ciolko, A. T.

Seven papers cover the following areas: design, construction and performance of lime, fly ash, and slag pavement; evaluation of heavily loaded cement stabilized bases; coal refuse and fly ash compositions; potential highway base course materials; lime soil mixture design considerations for soils of southeastern United States; short term active soil property changes caused by injection of lime and fly ash; soil cement for use in stream channel grade stabilization structures; and reaction products of lime treated southeastern soils.

Estimating the gaze of a virtuality human.

Science.gov (United States)

Roberts, David J; Rae, John; Duckworth, Tobias W; Moore, Carl M; Aspin, Rob

2013-04-01

The aim of our experiment is to determine if eye-gaze can be estimated from a virtuality human: to within the accuracies that underpin social interaction; and reliably across gaze poses and camera arrangements likely in every day settings. The scene is set by explaining why Immersive Virtuality Telepresence has the potential to meet the grand challenge of faithfully communicating both the appearance and the focus of attention of a remote human participant within a shared 3D computer-supported context. Within the experiment n=22 participants rotated static 3D virtuality humans, reconstructed from surround images, until they felt most looked at. The dependent variable was absolute angular error, which was compared to that underpinning social gaze behaviour in the natural world. Independent variables were 1) relative orientations of eye, head and body of captured subject; and 2) subset of cameras used to texture the form. Analysis looked for statistical and practical significance and qualitative corroborating evidence. The analysed results tell us much about the importance and detail of the relationship between gaze pose, method of video based reconstruction, and camera arrangement. They tell us that virtuality can reproduce gaze to an accuracy useful in social interaction, but with the adopted method of Video Based Reconstruction, this is highly dependent on combination of gaze pose and camera arrangement. This suggests changes in the VBR approach in order to allow more flexible camera arrangements. The work is of interest to those wanting to support expressive meetings that are both socially and spatially situated, and particular those using or building Immersive Virtuality Telepresence to accomplish this. It is also of relevance to the use of virtuality humans in applications ranging from the study of human interactions to gaming and the crossing of the stage line in films and TV.

The Gaze as constituent and annihilator

Directory of Open Access Journals (Sweden)

Mats Carlsson

2012-11-01

Full Text Available This article aims to join the contemporary effort to promote a psychoanalytic renaissance within cinema studies, post Post-Theory. In trying to shake off the burden of the 1970s film theory's distortion of the Lacanian Gaze, rejuvenating it with the strength of the Real and fusing it with Freudian thoughts on the uncanny, hopefully this new dawn can be reached. I aspire to conceptualize the Gaze in a straightforward manner. This in order to obtain an instrument for the identification of certain strategies within the filmic realm aimed at depicting the subjective destabilizing of diegetic characters as well as thwarting techniques directed at the spectorial subject. In setting this capricious Gaze against the uncanny phenomena described by Freud, we find that these two ideas easily intertwine into a draft description of a powerful, potentially reconstitutive force worth being highlighted.

In the presence of conflicting gaze cues, fearful expression and eye-size guide attention.

Science.gov (United States)

Carlson, Joshua M; Aday, Jacob

2017-10-19

Humans are social beings that often interact in multi-individual environments. As such, we are frequently confronted with nonverbal social signals, including eye-gaze direction, from multiple individuals. Yet, the factors that allow for the prioritisation of certain gaze cues over others are poorly understood. Using a modified conflicting gaze paradigm, we tested the hypothesis that fearful gaze would be favoured amongst competing gaze cues. We further hypothesised that this effect is related to the increased sclera exposure, which is characteristic of fearful expressions. Across three experiments, we found that fearful, but not happy, gaze guides observers' attention over competing non-emotional gaze. The guidance of attention by fearful gaze appears to be linked to increased sclera exposure. However, differences in sclera exposure do not prioritise competing gazes of other types. Thus, fearful gaze guides attention among competing cues and this effect is facilitated by increased sclera exposure - but increased sclera exposure per se does not guide attention. The prioritisation of fearful gaze over non-emotional gaze likely represents an adaptive means of selectively attending to survival-relevant spatial locations.

EYE GAZE TRACKING

DEFF Research Database (Denmark)

2017-01-01

This invention relates to a method of performing eye gaze tracking of at least one eye of a user, by determining the position of the center of the eye, said method comprising the steps of: detecting the position of at least three reflections on said eye, transforming said positions to spanning...... a normalized coordinate system spanning a frame of reference, wherein said transformation is performed based on a bilinear transformation or a non linear transformation e.g. a möbius transformation or a homographic transformation, detecting the position of said center of the eye relative to the position...... of said reflections and transforming this position to said normalized coordinate system, tracking the eye gaze by tracking the movement of said eye in said normalized coordinate system. Thereby calibration of a camera, such as knowledge of the exact position and zoom level of the camera, is avoided...

Eye gazing direction inspection based on image processing technique

Science.gov (United States)

Hao, Qun; Song, Yong

2005-02-01

According to the research result in neural biology, human eyes can obtain high resolution only at the center of view of field. In the research of Virtual Reality helmet, we design to detect the gazing direction of human eyes in real time and feed it back to the control system to improve the resolution of the graph at the center of field of view. In the case of current display instruments, this method can both give attention to the view field of virtual scene and resolution, and improve the immersion of virtual system greatly. Therefore, detecting the gazing direction of human eyes rapidly and exactly is the basis of realizing the design scheme of this novel VR helmet. In this paper, the conventional method of gazing direction detection that based on Purklinje spot is introduced firstly. In order to overcome the disadvantage of the method based on Purklinje spot, this paper proposed a method based on image processing to realize the detection and determination of the gazing direction. The locations of pupils and shapes of eye sockets change with the gazing directions. With the aid of these changes, analyzing the images of eyes captured by the cameras, gazing direction of human eyes can be determined finally. In this paper, experiments have been done to validate the efficiency of this method by analyzing the images. The algorithm can carry out the detection of gazing direction base on normal eye image directly, and it eliminates the need of special hardware. Experiment results show that the method is easy to implement and have high precision.

Latvijas gaze

International Nuclear Information System (INIS)

1994-04-01

A collection of photocopies of materials (such as overheads etc.) used at a seminar (organized by the Board of Directors of the company designated ''Latvijas Gaze'' in connection with The National Oil and Gas Company of Denmark, DONG) comprising an analysis of training needs with regard to marketing of gas technology and consultancy to countries in Europe, especially with regard to Latvia. (AB)

Robot Faces that Follow Gaze Facilitate Attentional Engagement and Increase Their Likeability

Science.gov (United States)

Willemse, Cesco; Marchesi, Serena; Wykowska, Agnieszka

2018-01-01

Gaze behavior of humanoid robots is an efficient mechanism for cueing our spatial orienting, but less is known about the cognitive–affective consequences of robots responding to human directional cues. Here, we examined how the extent to which a humanoid robot (iCub) avatar directed its gaze to the same objects as our participants affected engagement with the robot, subsequent gaze-cueing, and subjective ratings of the robot’s characteristic traits. In a gaze-contingent eyetracking task, participants were asked to indicate a preference for one of two objects with their gaze while an iCub avatar was presented between the object photographs. In one condition, the iCub then shifted its gaze toward the object chosen by a participant in 80% of the trials (joint condition) and in the other condition it looked at the opposite object 80% of the time (disjoint condition). Based on the literature in human–human social cognition, we took the speed with which the participants looked back at the robot as a measure of facilitated reorienting and robot-preference, and found these return saccade onset times to be quicker in the joint condition than in the disjoint condition. As indicated by results from a subsequent gaze-cueing tasks, the gaze-following behavior of the robot had little effect on how our participants responded to gaze cues. Nevertheless, subjective reports suggested that our participants preferred the iCub following participants’ gaze to the one with a disjoint attention behavior, rated it as more human-like and as more likeable. Taken together, our findings show a preference for robots who follow our gaze. Importantly, such subtle differences in gaze behavior are sufficient to influence our perception of humanoid agents, which clearly provides hints about the design of behavioral characteristics of humanoid robots in more naturalistic settings. PMID:29459842

Robot Faces that Follow Gaze Facilitate Attentional Engagement and Increase Their Likeability

Directory of Open Access Journals (Sweden)

Cesco Willemse

2018-02-01

Full Text Available Gaze behavior of humanoid robots is an efficient mechanism for cueing our spatial orienting, but less is known about the cognitive–affective consequences of robots responding to human directional cues. Here, we examined how the extent to which a humanoid robot (iCub avatar directed its gaze to the same objects as our participants affected engagement with the robot, subsequent gaze-cueing, and subjective ratings of the robot’s characteristic traits. In a gaze-contingent eyetracking task, participants were asked to indicate a preference for one of two objects with their gaze while an iCub avatar was presented between the object photographs. In one condition, the iCub then shifted its gaze toward the object chosen by a participant in 80% of the trials (joint condition and in the other condition it looked at the opposite object 80% of the time (disjoint condition. Based on the literature in human–human social cognition, we took the speed with which the participants looked back at the robot as a measure of facilitated reorienting and robot-preference, and found these return saccade onset times to be quicker in the joint condition than in the disjoint condition. As indicated by results from a subsequent gaze-cueing tasks, the gaze-following behavior of the robot had little effect on how our participants responded to gaze cues. Nevertheless, subjective reports suggested that our participants preferred the iCub following participants’ gaze to the one with a disjoint attention behavior, rated it as more human-like and as more likeable. Taken together, our findings show a preference for robots who follow our gaze. Importantly, such subtle differences in gaze behavior are sufficient to influence our perception of humanoid agents, which clearly provides hints about the design of behavioral characteristics of humanoid robots in more naturalistic settings.

Robot Faces that Follow Gaze Facilitate Attentional Engagement and Increase Their Likeability.

Science.gov (United States)

Willemse, Cesco; Marchesi, Serena; Wykowska, Agnieszka

2018-01-01

Gaze behavior of humanoid robots is an efficient mechanism for cueing our spatial orienting, but less is known about the cognitive-affective consequences of robots responding to human directional cues. Here, we examined how the extent to which a humanoid robot (iCub) avatar directed its gaze to the same objects as our participants affected engagement with the robot, subsequent gaze-cueing, and subjective ratings of the robot's characteristic traits. In a gaze-contingent eyetracking task, participants were asked to indicate a preference for one of two objects with their gaze while an iCub avatar was presented between the object photographs. In one condition, the iCub then shifted its gaze toward the object chosen by a participant in 80% of the trials (joint condition) and in the other condition it looked at the opposite object 80% of the time (disjoint condition). Based on the literature in human-human social cognition, we took the speed with which the participants looked back at the robot as a measure of facilitated reorienting and robot-preference, and found these return saccade onset times to be quicker in the joint condition than in the disjoint condition. As indicated by results from a subsequent gaze-cueing tasks, the gaze-following behavior of the robot had little effect on how our participants responded to gaze cues. Nevertheless, subjective reports suggested that our participants preferred the iCub following participants' gaze to the one with a disjoint attention behavior, rated it as more human-like and as more likeable. Taken together, our findings show a preference for robots who follow our gaze. Importantly, such subtle differences in gaze behavior are sufficient to influence our perception of humanoid agents, which clearly provides hints about the design of behavioral characteristics of humanoid robots in more naturalistic settings.

Eye blinking in an avian species is associated with gaze shifts.

Science.gov (United States)

Yorzinski, Jessica L

2016-08-30

Even when animals are actively monitoring their environment, they lose access to visual information whenever they blink. They can strategically time their blinks to minimize information loss and improve visual functioning but we have little understanding of how this process operates in birds. This study therefore examined blinking in freely-moving peacocks (Pavo cristatus) to determine the relationship between their blinks, gaze shifts, and context. Peacocks wearing a telemetric eye-tracker were exposed to a taxidermy predator (Vulpes vulpes) and their blinks and gaze shifts were recorded. Peacocks blinked during the majority of their gaze shifts, especially when gaze shifts were large, thereby timing their blinks to coincide with periods when visual information is already suppressed. They inhibited their blinks the most when they exhibited high rates of gaze shifts and were thus highly alert. Alternative hypotheses explaining the link between blinks and gaze shifts are discussed.

"The Gaze Heuristic:" Biography of an Adaptively Rational Decision Process.

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Hamlin, Robert P

2017-04-01

This article is a case study that describes the natural and human history of the gaze heuristic. The gaze heuristic is an interception heuristic that utilizes a single input (deviation from a constant angle of approach) repeatedly as a task is performed. Its architecture, advantages, and limitations are described in detail. A history of the gaze heuristic is then presented. In natural history, the gaze heuristic is the only known technique used by predators to intercept prey. In human history the gaze heuristic was discovered accidentally by Royal Air Force (RAF) fighter command just prior to World War II. As it was never discovered by the Luftwaffe, the technique conferred a decisive advantage upon the RAF throughout the war. After the end of the war in America, German technology was combined with the British heuristic to create the Sidewinder AIM9 missile, the most successful autonomous weapon ever built. There are no plans to withdraw it or replace its guiding gaze heuristic. The case study demonstrates that the gaze heuristic is a specific heuristic type that takes a single best input at the best time (take the best 2 ). Its use is an adaptively rational response to specific, rapidly evolving decision environments that has allowed those animals/humans/machines who use it to survive, prosper, and multiply relative to those who do not. Copyright © 2017 Cognitive Science Society, Inc.

Experimental test of spatial updating models for monkey eye-head gaze shifts.

Directory of Open Access Journals (Sweden)

Tom J Van Grootel

Full Text Available How the brain maintains an accurate and stable representation of visual target locations despite the occurrence of saccadic gaze shifts is a classical problem in oculomotor research. Here we test and dissociate the predictions of different conceptual models for head-unrestrained gaze-localization behavior of macaque monkeys. We adopted the double-step paradigm with rapid eye-head gaze shifts to measure localization accuracy in response to flashed visual stimuli in darkness. We presented the second target flash either before (static, or during (dynamic the first gaze displacement. In the dynamic case the brief visual flash induced a small retinal streak of up to about 20 deg at an unpredictable moment and retinal location during the eye-head gaze shift, which provides serious challenges for the gaze-control system. However, for both stimulus conditions, monkeys localized the flashed targets with accurate gaze shifts, which rules out several models of visuomotor control. First, these findings exclude the possibility that gaze-shift programming relies on retinal inputs only. Instead, they support the notion that accurate eye-head motor feedback updates the gaze-saccade coordinates. Second, in dynamic trials the visuomotor system cannot rely on the coordinates of the planned first eye-head saccade either, which rules out remapping on the basis of a predictive corollary gaze-displacement signal. Finally, because gaze-related head movements were also goal-directed, requiring continuous access to eye-in-head position, we propose that our results best support a dynamic feedback scheme for spatial updating in which visuomotor control incorporates accurate signals about instantaneous eye- and head positions rather than relative eye- and head displacements.

Gaze Behavior of Children with ASD toward Pictures of Facial Expressions.

Science.gov (United States)

Matsuda, Soichiro; Minagawa, Yasuyo; Yamamoto, Junichi

2015-01-01

Atypical gaze behavior in response to a face has been well documented in individuals with autism spectrum disorders (ASDs). Children with ASD appear to differ from typically developing (TD) children in gaze behavior for spoken and dynamic face stimuli but not for nonspeaking, static face stimuli. Furthermore, children with ASD and TD children show a difference in their gaze behavior for certain expressions. However, few studies have examined the relationship between autism severity and gaze behavior toward certain facial expressions. The present study replicated and extended previous studies by examining gaze behavior towards pictures of facial expressions. We presented ASD and TD children with pictures of surprised, happy, neutral, angry, and sad facial expressions. Autism severity was assessed using the Childhood Autism Rating Scale (CARS). The results showed that there was no group difference in gaze behavior when looking at pictures of facial expressions. Conversely, the children with ASD who had more severe autistic symptomatology had a tendency to gaze at angry facial expressions for a shorter duration in comparison to other facial expressions. These findings suggest that autism severity should be considered when examining atypical responses to certain facial expressions.

Anxiety symptoms and children's eye gaze during fear learning.

Science.gov (United States)

Michalska, Kalina J; Machlin, Laura; Moroney, Elizabeth; Lowet, Daniel S; Hettema, John M; Roberson-Nay, Roxann; Averbeck, Bruno B; Brotman, Melissa A; Nelson, Eric E; Leibenluft, Ellen; Pine, Daniel S

2017-11-01

The eye region of the face is particularly relevant for decoding threat-related signals, such as fear. However, it is unclear if gaze patterns to the eyes can be influenced by fear learning. Previous studies examining gaze patterns in adults find an association between anxiety and eye gaze avoidance, although no studies to date examine how associations between anxiety symptoms and eye-viewing patterns manifest in children. The current study examined the effects of learning and trait anxiety on eye gaze using a face-based fear conditioning task developed for use in children. Participants were 82 youth from a general population sample of twins (aged 9-13 years), exhibiting a range of anxiety symptoms. Participants underwent a fear conditioning paradigm where the conditioned stimuli (CS+) were two neutral faces, one of which was randomly selected to be paired with an aversive scream. Eye tracking, physiological, and subjective data were acquired. Children and parents reported their child's anxiety using the Screen for Child Anxiety Related Emotional Disorders. Conditioning influenced eye gaze patterns in that children looked longer and more frequently to the eye region of the CS+ than CS- face; this effect was present only during fear acquisition, not at baseline or extinction. Furthermore, consistent with past work in adults, anxiety symptoms were associated with eye gaze avoidance. Finally, gaze duration to the eye region mediated the effect of anxious traits on self-reported fear during acquisition. Anxiety symptoms in children relate to face-viewing strategies deployed in the context of a fear learning experiment. This relationship may inform attempts to understand the relationship between pediatric anxiety symptoms and learning. © 2017 Association for Child and Adolescent Mental Health.

The impact of visual gaze direction on auditory object tracking.

Science.gov (United States)

Pomper, Ulrich; Chait, Maria

2017-07-05

Subjective experience suggests that we are able to direct our auditory attention independent of our visual gaze, e.g when shadowing a nearby conversation at a cocktail party. But what are the consequences at the behavioural and neural level? While numerous studies have investigated both auditory attention and visual gaze independently, little is known about their interaction during selective listening. In the present EEG study, we manipulated visual gaze independently of auditory attention while participants detected targets presented from one of three loudspeakers. We observed increased response times when gaze was directed away from the locus of auditory attention. Further, we found an increase in occipital alpha-band power contralateral to the direction of gaze, indicative of a suppression of distracting input. Finally, this condition also led to stronger central theta-band power, which correlated with the observed effect in response times, indicative of differences in top-down processing. Our data suggest that a misalignment between gaze and auditory attention both reduce behavioural performance and modulate underlying neural processes. The involvement of central theta-band and occipital alpha-band effects are in line with compensatory neural mechanisms such as increased cognitive control and the suppression of task irrelevant inputs.

Simple gaze-contingent cues guide eye movements in a realistic driving simulator

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Pomarjanschi, Laura; Dorr, Michael; Bex, Peter J.; Barth, Erhardt

2013-03-01

Looking at the right place at the right time is a critical component of driving skill. Therefore, gaze guidance has the potential to become a valuable driving assistance system. In previous work, we have already shown that complex gaze-contingent stimuli can guide attention and reduce the number of accidents in a simple driving simulator. We here set out to investigate whether cues that are simple enough to be implemented in a real car can also capture gaze during a more realistic driving task in a high-fidelity driving simulator. We used a state-of-the-art, wide-field-of-view driving simulator with an integrated eye tracker. Gaze-contingent warnings were implemented using two arrays of light-emitting diodes horizontally fitted below and above the simulated windshield. Thirteen volunteering subjects drove along predetermined routes in a simulated environment popu­ lated with autonomous traffic. Warnings were triggered during the approach to half of the intersections, cueing either towards the right or to the left. The remaining intersections were not cued, and served as controls. The analysis of the recorded gaze data revealed that the gaze-contingent cues did indeed have a gaze guiding effect, triggering a significant shift in gaze position towards the highlighted direction. This gaze shift was not accompanied by changes in driving behaviour, suggesting that the cues do not interfere with the driving task itself.

Intermediate view synthesis for eye-gazing

Science.gov (United States)

Baek, Eu-Ttuem; Ho, Yo-Sung

2015-01-01

Nonverbal communication, also known as body language, is an important form of communication. Nonverbal behaviors such as posture, eye contact, and gestures send strong messages. In regard to nonverbal communication, eye contact is one of the most important forms that an individual can use. However, lack of eye contact occurs when we use video conferencing system. The disparity between locations of the eyes and a camera gets in the way of eye contact. The lock of eye gazing can give unapproachable and unpleasant feeling. In this paper, we proposed an eye gazing correction for video conferencing. We use two cameras installed at the top and the bottom of the television. The captured two images are rendered with 2D warping at virtual position. We implement view morphing to the detected face, and synthesize the face and the warped image. Experimental results verify that the proposed system is effective in generating natural gaze-corrected images.

Gaze-controlled Driving

DEFF Research Database (Denmark)

Tall, Martin; Alapetite, Alexandre; San Agustin, Javier

2009-01-01

We investigate if the gaze (point of regard) can control a remote vehicle driving on a racing track. Five different input devices (on-screen buttons, mouse-pointing low-cost webcam eye tracker and two commercial eye tracking systems) provide heading and speed control on the scene view transmitted...

Speaking and Listening with the Eyes: Gaze Signaling during Dyadic Interactions.

Science.gov (United States)

Ho, Simon; Foulsham, Tom; Kingstone, Alan

2015-01-01

Cognitive scientists have long been interested in the role that eye gaze plays in social interactions. Previous research suggests that gaze acts as a signaling mechanism and can be used to control turn-taking behaviour. However, early research on this topic employed methods of analysis that aggregated gaze information across an entire trial (or trials), which masks any temporal dynamics that may exist in social interactions. More recently, attempts have been made to understand the temporal characteristics of social gaze but little research has been conducted in a natural setting with two interacting participants. The present study combines a temporally sensitive analysis technique with modern eye tracking technology to 1) validate the overall results from earlier aggregated analyses and 2) provide insight into the specific moment-to-moment temporal characteristics of turn-taking behaviour in a natural setting. Dyads played two social guessing games (20 Questions and Heads Up) while their eyes were tracked. Our general results are in line with past aggregated data, and using cross-correlational analysis on the specific gaze and speech signals of both participants we found that 1) speakers end their turn with direct gaze at the listener and 2) the listener in turn begins to speak with averted gaze. Convergent with theoretical models of social interaction, our data suggest that eye gaze can be used to signal both the end and the beginning of a speaking turn during a social interaction. The present study offers insight into the temporal dynamics of live dyadic interactions and also provides a new method of analysis for eye gaze data when temporal relationships are of interest.

Speaking and Listening with the Eyes: Gaze Signaling during Dyadic Interactions.

Directory of Open Access Journals (Sweden)

Simon Ho

Full Text Available Cognitive scientists have long been interested in the role that eye gaze plays in social interactions. Previous research suggests that gaze acts as a signaling mechanism and can be used to control turn-taking behaviour. However, early research on this topic employed methods of analysis that aggregated gaze information across an entire trial (or trials, which masks any temporal dynamics that may exist in social interactions. More recently, attempts have been made to understand the temporal characteristics of social gaze but little research has been conducted in a natural setting with two interacting participants. The present study combines a temporally sensitive analysis technique with modern eye tracking technology to 1 validate the overall results from earlier aggregated analyses and 2 provide insight into the specific moment-to-moment temporal characteristics of turn-taking behaviour in a natural setting. Dyads played two social guessing games (20 Questions and Heads Up while their eyes were tracked. Our general results are in line with past aggregated data, and using cross-correlational analysis on the specific gaze and speech signals of both participants we found that 1 speakers end their turn with direct gaze at the listener and 2 the listener in turn begins to speak with averted gaze. Convergent with theoretical models of social interaction, our data suggest that eye gaze can be used to signal both the end and the beginning of a speaking turn during a social interaction. The present study offers insight into the temporal dynamics of live dyadic interactions and also provides a new method of analysis for eye gaze data when temporal relationships are of interest.

Gaze Behavior, Believability, Likability and the iCat

NARCIS (Netherlands)

Poel, Mannes; Heylen, Dirk K.J.; Meulemans, M.; Nijholt, Antinus; Stock, O.; Nishida, T.

2007-01-01

The iCat is a user-interface robot with the ability to express a range of emotions through its facial features. This paper summarizes our research whether we can increase the believability and likability of the iCat for its human partners through the application of gaze behaviour. Gaze behaviour

Gaze Behavior, Believability, Likability and the iCat

NARCIS (Netherlands)

Nijholt, Antinus; Poel, Mannes; Heylen, Dirk K.J.; Stock, O.; Nishida, T.; Meulemans, M.; van Bremen, A.

2009-01-01

The iCat is a user-interface robot with the ability to express a range of emotions through its facial features. This paper summarizes our research whether we can increase the believability and likability of the iCat for its human partners through the application of gaze behaviour. Gaze behaviour

"Wolves (Canis lupus) and dogs (Canis familiaris) differ in following human gaze into distant space but respond similar to their packmates' gaze": Correction to Werhahn et al. (2016).

Science.gov (United States)

2017-02-01

Reports an error in "Wolves ( Canis lupus ) and dogs ( Canis familiaris ) differ in following human gaze into distant space but respond similar to their packmates' gaze" by Geraldine Werhahn, Zsófia Virányi, Gabriela Barrera, Andrea Sommese and Friederike Range ( Journal of Comparative Psychology , 2016[Aug], Vol 130[3], 288-298). In the article, the affiliations for the second and fifth authors should be Wolf Science Center, Ernstbrunn, Austria, and Comparative Cognition, Messerli Research Institute, University of Veterinary Medicine Vienna/ Medical University of Vienna/University of Vienna. The online version of this article has been corrected. (The following abstract of the original article appeared in record 2016-26311-001.) Gaze following into distant space is defined as visual co-orientation with another individual's head direction allowing the gaze follower to gain information on its environment. Human and nonhuman animals share this basic gaze following behavior, suggested to rely on a simple reflexive mechanism and believed to be an important prerequisite for complex forms of social cognition. Pet dogs differ from other species in that they follow only communicative human gaze clearly addressed to them. However, in an earlier experiment we showed that wolves follow human gaze into distant space. Here we set out to investigate whether domestication has affected gaze following in dogs by comparing pack-living dogs and wolves raised and kept under the same conditions. In Study 1 we found that in contrast to the wolves, these dogs did not follow minimally communicative human gaze into distant space in the same test paradigm. In the observational Study 2 we found that pack-living dogs and wolves, similarly vigilant to environmental stimuli, follow the spontaneous gaze of their conspecifics similarly often. Our findings suggest that domestication did not affect the gaze following ability of dogs itself. The results raise hypotheses about which other dog skills

Early Left Parietal Activity Elicited by Direct Gaze: A High-Density EEG Study

Science.gov (United States)

Burra, Nicolas; Kerzel, Dirk; George, Nathalie

2016-01-01

Gaze is one of the most important cues for human communication and social interaction. In particular, gaze contact is the most primary form of social contact and it is thought to capture attention. A very early-differentiated brain response to direct versus averted gaze has been hypothesized. Here, we used high-density electroencephalography to test this hypothesis. Topographical analysis allowed us to uncover a very early topographic modulation (40–80 ms) of event-related responses to faces with direct as compared to averted gaze. This modulation was obtained only in the condition where intact broadband faces–as opposed to high-pass or low-pas filtered faces–were presented. Source estimation indicated that this early modulation involved the posterior parietal region, encompassing the left precuneus and inferior parietal lobule. This supports the idea that it reflected an early orienting response to direct versus averted gaze. Accordingly, in a follow-up behavioural experiment, we found faster response times to the direct gaze than to the averted gaze broadband faces. In addition, classical evoked potential analysis showed that the N170 peak amplitude was larger for averted gaze than for direct gaze. Taken together, these results suggest that direct gaze may be detected at a very early processing stage, involving a parallel route to the ventral occipito-temporal route of face perceptual analysis. PMID:27880776

Gaze behaviour during space perception and spatial decision making.

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Wiener, Jan M; Hölscher, Christoph; Büchner, Simon; Konieczny, Lars

2012-11-01

A series of four experiments investigating gaze behavior and decision making in the context of wayfinding is reported. Participants were presented with screenshots of choice points taken in large virtual environments. Each screenshot depicted alternative path options. In Experiment 1, participants had to decide between them to find an object hidden in the environment. In Experiment 2, participants were first informed about which path option to take as if following a guided route. Subsequently, they were presented with the same images in random order and had to indicate which path option they chose during initial exposure. In Experiment 1, we demonstrate (1) that participants have a tendency to choose the path option that featured the longer line of sight, and (2) a robust gaze bias towards the eventually chosen path option. In Experiment 2, systematic differences in gaze behavior towards the alternative path options between encoding and decoding were observed. Based on data from Experiments 1 and 2 and two control experiments ensuring that fixation patterns were specific to the spatial tasks, we develop a tentative model of gaze behavior during wayfinding decision making suggesting that particular attention was paid to image areas depicting changes in the local geometry of the environments such as corners, openings, and occlusions. Together, the results suggest that gaze during a wayfinding tasks is directed toward, and can be predicted by, a subset of environmental features and that gaze bias effects are a general phenomenon of visual decision making.

Investigating the Link Between Radiologists Gaze, Diagnostic Decision, and Image Content

Energy Technology Data Exchange (ETDEWEB)

Tourassi, Georgia [ORNL; Voisin, Sophie [ORNL; Paquit, Vincent C [ORNL; Krupinski, Elizabeth [University of Arizona

2013-01-01

Objective: To investigate machine learning for linking image content, human perception, cognition, and error in the diagnostic interpretation of mammograms. Methods: Gaze data and diagnostic decisions were collected from six radiologists who reviewed 20 screening mammograms while wearing a head-mounted eye-tracker. Texture analysis was performed in mammographic regions that attracted radiologists attention and in all abnormal regions. Machine learning algorithms were investigated to develop predictive models that link: (i) image content with gaze, (ii) image content and gaze with cognition, and (iii) image content, gaze, and cognition with diagnostic error. Both group-based and individualized models were explored. Results: By pooling the data from all radiologists machine learning produced highly accurate predictive models linking image content, gaze, cognition, and error. Merging radiologists gaze metrics and cognitive opinions with computer-extracted image features identified 59% of the radiologists diagnostic errors while confirming 96.2% of their correct diagnoses. The radiologists individual errors could be adequately predicted by modeling the behavior of their peers. However, personalized tuning appears to be beneficial in many cases to capture more accurately individual behavior. Conclusions: Machine learning algorithms combining image features with radiologists gaze data and diagnostic decisions can be effectively developed to recognize cognitive and perceptual errors associated with the diagnostic interpretation of mammograms.

The Politics of the Gaze Foucault, Lacan and Zizek

Directory of Open Access Journals (Sweden)

Henry Krips

2010-03-01

Full Text Available Joan Copjec accuses orthodox film theory of misrepresenting the Lacanian gaze by assimilating it to Foucauldian panopticon (Copjec 1994: 18-19. Although Copjec is correct that orthodox film theory misrepresents the Lacanian gaze, she, in turn, misrepresents Foucault by choosing to focus exclusively upon those as-pects of his work on the panopticon that have been taken up by orthodox film the-ory (Copjec 1994: 4. In so doing, I argue, Copjec misses key parallels between the Lacanian and Foucauldian concepts of the gaze. More than a narrow academic dispute about how to read Foucault and Lacan, this debate has wider political sig-nificance. In particular, using Slavoj Zizek's work, I show that a correct account of the panoptic gaze leads us to rethink the question of how to oppose modern techniques of surveillance.

A testimony to Muzil: Hervé Guibert, Foucault, and the medical gaze.

Science.gov (United States)

Rendell, Joanne

2004-01-01

Testimony to Muzil: Hervé Guibert, Michel Foucault, and the "Medical Gaze" examines the fictional/autobiographical AIDS writings of the French writer Hervé Guibert. Locating Guibert's writings alongside the work of his friend Michel Foucault, the article explores how they echo Foucault's evolving notions of the "medical gaze." The article also explores how Guilbert's narrators and Guibert himself (as writer) resist and challenge the medical gaze; a gaze which particularly in the era of AIDS has subjected, objectified, and even sometimes punished the body of the gay man. It is argued that these resistances to the gaze offer a literary extension to Foucault's later work on power and resistance strategies.

Human-like object tracking and gaze estimation with PKD android.

Science.gov (United States)

Wijayasinghe, Indika B; Miller, Haylie L; Das, Sumit K; Bugnariu, Nicoleta L; Popa, Dan O

2016-05-01

As the use of robots increases for tasks that require human-robot interactions, it is vital that robots exhibit and understand human-like cues for effective communication. In this paper, we describe the implementation of object tracking capability on Philip K. Dick (PKD) android and a gaze tracking algorithm, both of which further robot capabilities with regard to human communication. PKD's ability to track objects with human-like head postures is achieved with visual feedback from a Kinect system and an eye camera. The goal of object tracking with human-like gestures is twofold : to facilitate better human-robot interactions and to enable PKD as a human gaze emulator for future studies. The gaze tracking system employs a mobile eye tracking system (ETG; SensoMotoric Instruments) and a motion capture system (Cortex; Motion Analysis Corp.) for tracking the head orientations. Objects to be tracked are displayed by a virtual reality system, the Computer Assisted Rehabilitation Environment (CAREN; MotekForce Link). The gaze tracking algorithm converts eye tracking data and head orientations to gaze information facilitating two objectives: to evaluate the performance of the object tracking system for PKD and to use the gaze information to predict the intentions of the user, enabling the robot to understand physical cues by humans.

Human-like object tracking and gaze estimation with PKD android

Science.gov (United States)

Wijayasinghe, Indika B.; Miller, Haylie L.; Das, Sumit K.; Bugnariu, Nicoleta L.; Popa, Dan O.

2016-05-01

As the use of robots increases for tasks that require human-robot interactions, it is vital that robots exhibit and understand human-like cues for effective communication. In this paper, we describe the implementation of object tracking capability on Philip K. Dick (PKD) android and a gaze tracking algorithm, both of which further robot capabilities with regard to human communication. PKD's ability to track objects with human-like head postures is achieved with visual feedback from a Kinect system and an eye camera. The goal of object tracking with human-like gestures is twofold: to facilitate better human-robot interactions and to enable PKD as a human gaze emulator for future studies. The gaze tracking system employs a mobile eye tracking system (ETG; SensoMotoric Instruments) and a motion capture system (Cortex; Motion Analysis Corp.) for tracking the head orientations. Objects to be tracked are displayed by a virtual reality system, the Computer Assisted Rehabilitation Environment (CAREN; MotekForce Link). The gaze tracking algorithm converts eye tracking data and head orientations to gaze information facilitating two objectives: to evaluate the performance of the object tracking system for PKD and to use the gaze information to predict the intentions of the user, enabling the robot to understand physical cues by humans.

Utilizing Gaze Behavior for Inferring Task Transitions Using Abstract Hidden Markov Models

Directory of Open Access Journals (Sweden)

Daniel Fernando Tello Gamarra

2016-12-01

Full Text Available We demonstrate an improved method for utilizing observed gaze behavior and show that it is useful in inferring hand movement intent during goal directed tasks. The task dynamics and the relationship between hand and gaze behavior are learned using an Abstract Hidden Markov Model (AHMM. We show that the predicted hand movement transitions occur consistently earlier in AHMM models with gaze than those models that do not include gaze observations.

Towards Wearable Gaze Supported Augmented Cognition

DEFF Research Database (Denmark)

Toshiaki Kurauchi, Andrew; Hitoshi Morimoto, Carlos; Mardanbeigi, Diako

Augmented cognition applications must deal with the problem of how to exhibit information in an orderly, understandable, and timely fashion. Though context have been suggested to control the kind, amount, and timing of the information delivered, we argue that gaze can be a fundamental tool...... by the wearable computing community to develop a gaze supported augmented cognition application with three interaction modes. The application provides information of the person being looked at. The continuous mode updates information every time the user looks at a different face. The key activated discrete mode...

Trait Anxiety Impacts the Perceived Gaze Direction of Fearful But Not Angry Faces

Directory of Open Access Journals (Sweden)

Zhonghua Hu

2017-07-01

Full Text Available Facial expression and gaze direction play an important role in social communication. Previous research has demonstrated the perception of anger is enhanced by direct gaze, whereas, it is unclear whether perception of fear is enhanced by averted gaze. In addition, previous research has shown the anxiety affects the processing of facial expression and gaze direction, but hasn’t measured or controlled for depression. As a result, firm conclusions cannot be made regarding the impact of individual differences in anxiety and depression on perceptions of face expressions and gaze direction. The current study attempted to reexamine the effect of the anxiety level on the processing of facial expressions and gaze direction by matching participants on depression scores. A reliable psychophysical index of the range of eye gaze angles judged as being directed at oneself [the cone of direct gaze (CoDG] was used as the dependent variable in this study. Participants were stratified into high/low trait anxiety groups and asked to judge the gaze of angry, fearful, and neutral faces across a range of gaze directions. The result showed: (1 the perception of gaze direction was influenced by facial expression and this was modulated by trait anxiety. For the high trait anxiety group, the CoDG for angry expressions was wider than for fearful and neutral expressions, and no significant difference emerged between fearful and neutral expressions; For the low trait anxiety group, the CoDG for both angry and fearful expressions was wider than for neutral, and no significant difference emerged between angry and fearful expressions. (2 Trait anxiety modulated the perception of gaze direction only in the fearful condition, such that the fearful CoDG for the high trait anxiety group was narrower than the low trait anxiety group. This demonstrated that anxiety distinctly affected gaze perception in expressions that convey threat (angry, fearful, such that a high trait anxiety

The impact of visual gaze direction on auditory object tracking

OpenAIRE

Pomper, U.; Chait, M.

2017-01-01

Subjective experience suggests that we are able to direct our auditory attention independent of our visual gaze, e.g when shadowing a nearby conversation at a cocktail party. But what are the consequences at the behavioural and neural level? While numerous studies have investigated both auditory attention and visual gaze independently, little is known about their interaction during selective listening. In the present EEG study, we manipulated visual gaze independently of auditory attention wh...

Watch out! Magnetoencephalographic evidence for early modulation of attention orienting by fearful gaze cueing.

Directory of Open Access Journals (Sweden)

Fanny Lachat

Full Text Available Others' gaze and emotional facial expression are important cues for the process of attention orienting. Here, we investigated with magnetoencephalography (MEG whether the combination of averted gaze and fearful expression may elicit a selectively early effect of attention orienting on the brain responses to targets. We used the direction of gaze of centrally presented fearful and happy faces as the spatial attention orienting cue in a Posner-like paradigm where the subjects had to detect a target checkerboard presented at gazed-at (valid trials or non gazed-at (invalid trials locations of the screen. We showed that the combination of averted gaze and fearful expression resulted in a very early attention orienting effect in the form of additional parietal activity between 55 and 70 ms for the valid versus invalid targets following fearful gaze cues. No such effect was obtained for the targets following happy gaze cues. This early cue-target validity effect selective of fearful gaze cues involved the left superior parietal region and the left lateral middle occipital region. These findings provide the first evidence for an effect of attention orienting induced by fearful gaze in the time range of C1. In doing so, they demonstrate the selective impact of combined gaze and fearful expression cues in the process of attention orienting.

Continuous CO2 capture and MSWI fly ash stabilization, utilizing novel dynamic equipment

International Nuclear Information System (INIS)

Jiang Jianguo; Du Xuejuan; Chen Maozhe; Zhang Chang

2009-01-01

Novel dynamic equipment with gas in and out continuously was developed to study the capture capacity of CO 2 . Municipal solid waste incineration (MSWI) fly ash has a high capture rate of CO 2 in CO 2 -rich gas. Fly ash can sequester pure CO 2 rapidly, and its capacity is 16.3 g CO 2 /100 g fly ash with no water added and 21.4 g CO 2 /100 g fly ash with 20% water added. For simulated incineration gas containing 12% CO 2 , the capture rate decreased and the capacity was 13.2 g CO 2 /100 g fly ash with no water added and 18.5 g CO 2 /100 g fly ash with 20% water added. After accelerated carbonation, the C and O contents increased, indicating CO 2 capture in the fly ash; CO 2 combines with Ca(OH) 2 to form CaCO 3 , which increased the CaCO 3 content from 12.5 to 54.3%. The leaching of Pb markedly decreased from 24.48 to 0.111 mg/L. - Novel dynamic equipment designed to capture CO 2 by fly ash is more suitable for engineering application.

Stabilization of lead and copper contaminated firing range soil using calcined oyster shells and fly ash.

Science.gov (United States)

Moon, Deok Hyun; Park, Jae-Woo; Cheong, Kyung Hoon; Hyun, Seunghun; Koutsospyros, Agamemnon; Park, Jeong-Hun; Ok, Yong Sik

2013-12-01

A stabilization/solidification treatment scheme was devised to stabilize Pb and Cu contaminated soil from a firing range using renewable waste resources as additives, namely waste oyster shells (WOS) and fly ash (FA). The WOS, serving as the primary stabilizing agent, was pre-treated at a high temperature to activate quicklime from calcite. Class C FA was used as a secondary additive along with the calcined oyster shells (COS). The effectiveness of the treatment was evaluated by means of the toxicity characteristic leaching procedure (TCLP) and the 0.1 M HCl extraction tests following a curing period of 28 days. The combined treatment with 10 wt% COS and 5 wt% FA cause a significant reduction in Pb (>98 %) and Cu (>96 %) leachability which was indicated by the results from both extraction tests (TCLP and 0.1 M HCl). Scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDX) analyses are used to investigate the mechanism responsible for Pb and Cu stabilization. SEM-EDX results indicate that effective Pb and Cu immobilization using the combined COS-FA treatment is most probably associated with ettringite and pozzolanic reaction products. The treatment results suggest that the combined COS-FA treatment is a cost effective method for the stabilization of firing range soil.

Use of cement-fly ash-based stabilization techniques for the treatment of waste containing aromatic contaminants

Science.gov (United States)

Banaszkiewicz, Kamil; Marcinkowski, Tadeusz

2017-11-01

Research on evaluation of evaporation rate of volatile organic compounds from soil beds during processing is presented. For the experiment, soil samples were prepared with the same amounts of benzene and stabilized using a mixture of CEMI 42.5R cement and fly ash from pit-coal combustion. Solidification of soils contaminated with BTEX hydrocarbons using hydraulic binders involves a risk of releasing vapours of these compounds during homogenization of waste with stabilizing mixture introduced and its dilution with water. The primary purposes of the research were: analysis of benzene volume emitted from soil during stabilization/solidification process and characterization of factors that may negatively affect the quality of measurements/the course of stabilization process. Analysis of benzene emission intensity during the process was based on concentration (C6H6) values, recorded with flame-ionization detector above the surface of reacting mixture. At the same time, gaseous contaminants emitted during waste stabilization were passed through pipes filled with activated carbon (SCK, Anasorb CSC). Benzene vapours adsorbed on activated carbon were subjected to analysis using gas chromatograph Varian 450-GC. Evaporation characteristics of benzene during processing contaminated soils revealed the stages creating the highest danger to workers' health, as well as a need for actions connected with modification of technological line.

Investigating the link between radiologists’ gaze, diagnostic decision, and image content

Science.gov (United States)

Tourassi, Georgia; Voisin, Sophie; Paquit, Vincent; Krupinski, Elizabeth

2013-01-01

Objective To investigate machine learning for linking image content, human perception, cognition, and error in the diagnostic interpretation of mammograms. Methods Gaze data and diagnostic decisions were collected from three breast imaging radiologists and three radiology residents who reviewed 20 screening mammograms while wearing a head-mounted eye-tracker. Image analysis was performed in mammographic regions that attracted radiologists’ attention and in all abnormal regions. Machine learning algorithms were investigated to develop predictive models that link: (i) image content with gaze, (ii) image content and gaze with cognition, and (iii) image content, gaze, and cognition with diagnostic error. Both group-based and individualized models were explored. Results By pooling the data from all readers, machine learning produced highly accurate predictive models linking image content, gaze, and cognition. Potential linking of those with diagnostic error was also supported to some extent. Merging readers’ gaze metrics and cognitive opinions with computer-extracted image features identified 59% of the readers’ diagnostic errors while confirming 97.3% of their correct diagnoses. The readers’ individual perceptual and cognitive behaviors could be adequately predicted by modeling the behavior of others. However, personalized tuning was in many cases beneficial for capturing more accurately individual behavior. Conclusions There is clearly an interaction between radiologists’ gaze, diagnostic decision, and image content which can be modeled with machine learning algorithms. PMID:23788627

Face and gaze perception in borderline personality disorder: An electrical neuroimaging study.

Science.gov (United States)

Berchio, Cristina; Piguet, Camille; Gentsch, Kornelia; Küng, Anne-Lise; Rihs, Tonia A; Hasler, Roland; Aubry, Jean-Michel; Dayer, Alexandre; Michel, Christoph M; Perroud, Nader

2017-11-30

Humans are sensitive to gaze direction from early life, and gaze has social and affective values. Borderline personality disorder (BPD) is a clinical condition characterized by emotional dysregulation and enhanced sensitivity to affective and social cues. In this study we wanted to investigate the temporal-spatial dynamics of spontaneous gaze processing in BPD. We used a 2-back-working-memory task, in which neutral faces with direct and averted gaze were presented. Gaze was used as an emotional modulator of event-related-potentials to faces. High density EEG data were acquired in 19 females with BPD and 19 healthy women, and analyzed with a spatio-temporal microstates analysis approach. Independently of gaze direction, BPD patients showed altered N170 and P200 topographies for neutral faces. Source localization revealed that the anterior cingulate and other prefrontal regions were abnormally activated during the N170 component related to face encoding, while middle temporal deactivations were observed during the P200 component. Post-task affective ratings showed that BPD patients had difficulty to disambiguate neutral gaze. This study provides first evidence for an early neural bias toward neutral faces in BPD independent of gaze direction and also suggests the importance of considering basic aspects of social cognition in identifying biological risk factors of BPD. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Conflict Tasks of Different Types Divergently Affect the Attentional Processing of Gaze and Arrow.

Science.gov (United States)

Fan, Lingxia; Yu, Huan; Zhang, Xuemin; Feng, Qing; Sun, Mengdan; Xu, Mengsi

2018-01-01

The present study explored the attentional processing mechanisms of gaze and arrow cues in two different types of conflict tasks. In Experiment 1, participants performed a flanker task in which gaze and arrow cues were presented as central targets or bilateral distractors. The congruency between the direction of the target and the distractors was manipulated. Results showed that arrow distractors greatly interfered with the attentional processing of gaze, while the processing of arrow direction was immune to conflict from gaze distractors. Using a spatial compatibility task, Experiment 2 explored the conflict effects exerted on gaze and arrow processing by their relative spatial locations. When the direction of the arrow was in conflict with its spatial layout on screen, response times were slowed; however, the encoding of gaze was unaffected by spatial location. In general, processing to an arrow cue is less influenced by bilateral gaze cues but is affected by irrelevant spatial information, while processing to a gaze cue is greatly disturbed by bilateral arrows but is unaffected by irrelevant spatial information. Different effects on gaze and arrow cues by different types of conflicts may reflect two relatively distinct specific modes of the attentional process.

Interaction between gaze and visual and proprioceptive position judgements.

Science.gov (United States)

Fiehler, Katja; Rösler, Frank; Henriques, Denise Y P

2010-06-01

There is considerable evidence that targets for action are represented in a dynamic gaze-centered frame of reference, such that each gaze shift requires an internal updating of the target. Here, we investigated the effect of eye movements on the spatial representation of targets used for position judgements. Participants had their hand passively placed to a location, and then judged whether this location was left or right of a remembered visual or remembered proprioceptive target, while gaze direction was varied. Estimates of position of the remembered targets relative to the unseen position of the hand were assessed with an adaptive psychophysical procedure. These positional judgements significantly varied relative to gaze for both remembered visual and remembered proprioceptive targets. Our results suggest that relative target positions may also be represented in eye-centered coordinates. This implies similar spatial reference frames for action control and space perception when positions are coded relative to the hand.

Strange-face illusions during inter-subjective gazing.

Science.gov (United States)

Caputo, Giovanni B

2013-03-01

In normal observers, gazing at one's own face in the mirror for a few minutes, at a low illumination level, triggers the perception of strange faces, a new visual illusion that has been named 'strange-face in the mirror'. Individuals see huge distortions of their own faces, but they often see monstrous beings, archetypal faces, faces of relatives and deceased, and animals. In the experiment described here, strange-face illusions were perceived when two individuals, in a dimly lit room, gazed at each other in the face. Inter-subjective gazing compared to mirror-gazing produced a higher number of different strange-faces. Inter-subjective strange-face illusions were always dissociative of the subject's self and supported moderate feeling of their reality, indicating a temporary lost of self-agency. Unconscious synchronization of event-related responses to illusions was found between members in some pairs. Synchrony of illusions may indicate that unconscious response-coordination is caused by the illusion-conjunction of crossed dissociative strange-faces, which are perceived as projections into each other's visual face of reciprocal embodied representations within the pair. Inter-subjective strange-face illusions may be explained by the subject's embodied representations (somaesthetic, kinaesthetic and motor facial pattern) and the other's visual face binding. Unconscious facial mimicry may promote inter-subjective illusion-conjunction, then unconscious joint-action and response-coordination. Copyright © 2012 Elsevier Inc. All rights reserved.

Gaze3DFix: Detecting 3D fixations with an ellipsoidal bounding volume.

Science.gov (United States)

Weber, Sascha; Schubert, Rebekka S; Vogt, Stefan; Velichkovsky, Boris M; Pannasch, Sebastian

2017-10-26

Nowadays, the use of eyetracking to determine 2-D gaze positions is common practice, and several approaches to the detection of 2-D fixations exist, but ready-to-use algorithms to determine eye movements in three dimensions are still missing. Here we present a dispersion-based algorithm with an ellipsoidal bounding volume that estimates 3D fixations. Therefore, 3D gaze points are obtained using a vector-based approach and are further processed with our algorithm. To evaluate the accuracy of our method, we performed experimental studies with real and virtual stimuli. We obtained good congruence between stimulus position and both the 3D gaze points and the 3D fixation locations within the tested range of 200-600 mm. The mean deviation of the 3D fixations from the stimulus positions was 17 mm for the real as well as for the virtual stimuli, with larger variances at increasing stimulus distances. The described algorithms are implemented in two dynamic linked libraries (Gaze3D.dll and Fixation3D.dll), and we provide a graphical user interface (Gaze3DFixGUI.exe) that is designed for importing 2-D binocular eyetracking data and calculating both 3D gaze points and 3D fixations using the libraries. The Gaze3DFix toolkit, including both libraries and the graphical user interface, is available as open-source software at https://github.com/applied-cognition-research/Gaze3DFix .

Wearable Gaze Trackers: Mapping Visual Attention in 3D

DEFF Research Database (Denmark)

Jensen, Rasmus Ramsbøl; Stets, Jonathan Dyssel; Suurmets, Seidi

2017-01-01

gaze trackers allows respondents to move freely in any real world 3D environment, removing the previous restrictions. In this paper we propose a novel approach for processing visual attention of respondents using mobile wearable gaze trackers in a 3D environment. The pipeline consists of 3 steps...

Investigating social gaze as an action-perception online performance

Directory of Open Access Journals (Sweden)

Ouriel eGrynszpan

2012-04-01

Full Text Available In interpersonal interactions, linguistic information is complemented by non-linguistic information originating largely from facial expressions. The study of online face-to-face social interaction thus entails investigating the multimodal simultaneous processing of oral and visual percepts. Moreover, gaze in and of itself functions as a powerful communicative channel. In this respect, gaze should not be examined as a purely perceptive process but also as an active social performance. We designed a task involving multimodal deciphering of social information based on virtual characters, embedded in naturalistic backgrounds, who directly address the participant with non-literal speech and meaningful facial expressions. Eighteen adult participants were to interpret an equivocal sentence which could be disambiguated by examining the emotional expressions of the character speaking to them face-to-face. To examine self-control and self-awareness of gaze in this context, visual feedback is provided to the participant by a real-time gaze-contingent viewing window centered on the focal point, while the rest of the display is blurred. Eye-tracking data showed that the viewing window induced changes in gaze behaviour, notably longer visual fixations. Notwithstanding, only half the participants ascribed the window displacements to their eye movements. These results highlight the dissociation between non volitional gaze adaptation and self-ascription of agency. Such dissociation provides support for a two-step account of the sense of agency composed of pre-noetic monitoring mechanisms and reflexive processes. We comment upon these results, which illustrate the relevance of our method for studying online social cognition, especially concerning Autism Spectrum Disorders (ASD where poor pragmatic understanding of oral speech are considered linked to visual peculiarities that impede face exploration.

Investigating social gaze as an action-perception online performance.

Science.gov (United States)

Grynszpan, Ouriel; Simonin, Jérôme; Martin, Jean-Claude; Nadel, Jacqueline

2012-01-01

Gaze represents a major non-verbal communication channel in social interactions. In this respect, when facing another person, one's gaze should not be examined as a purely perceptive process but also as an action-perception online performance. However, little is known about processes involved in the real-time self-regulation of social gaze. The present study investigates the impact of a gaze-contingent viewing window on fixation patterns and the awareness of being the agent moving the window. In face-to-face scenarios played by a virtual human character, the task for the 18 adult participants was to interpret an equivocal sentence which could be disambiguated by examining the emotional expressions of the character speaking. The virtual character was embedded in naturalistic backgrounds to enhance realism. Eye-tracking data showed that the viewing window induced changes in gaze behavior, notably longer visual fixations. Notwithstanding, only half of the participants ascribed the window displacements to their eye movements. These participants also spent more time looking at the eyes and mouth regions of the virtual human character. The outcomes of the study highlight the dissociation between non-volitional gaze adaptation and the self-ascription of agency. Such dissociation provides support for a two-step account of the sense of agency composed of pre-noetic monitoring mechanisms and reflexive processes, linked by bottom-up and top-down processes. We comment upon these results, which illustrate the relevance of our method for studying online social cognition, in particular concerning autism spectrum disorders (ASD) where the poor pragmatic understanding of oral speech is considered linked to visual peculiarities that impede facial exploration.

Gaze and power. A post-structuralist interpretation on Perseus’ myth

Directory of Open Access Journals (Sweden)

Olaya Fernández Guerrero

2015-12-01

Full Text Available Gaze hierarchizes, manages and labels reality. Then, according to Foucault, gaze can be understood as a practice of power. This paper is inspired by his theories, and it applies them to one of the most powerful symbolic spheres of Western culture: Greek Myths. Notions such as visibility, invisibility and panopticism bring new light into the story of Perseus and Medusa, and they enable a re-reading of this Myth focused on the different ways of power that emerge from the gaze.

Predicting gaze direction from head pose yaw and pitch

NARCIS (Netherlands)

Johnson, D.O.; Cuijpers, R.H.; Arabnia, H.R.; Deligiannidis, L.; Lu, J.; Tinetti, F.G.; You, J.

2013-01-01

Abstract - Socially assistive robots (SARs) must be able to interpret non-verbal communication from a human. A person’s gaze direction informs the observer where the visual attention is directed to. Therefore it is useful if a robot can interpret the gaze direction, so that it can assess whether a

Thermo-mechanical properties and microfabric of fly ash-stabilized gold tailings.

Science.gov (United States)

Lee, Joon Kyu; Shang, Julie Q; Jeong, Sangseom

2014-07-15

This paper studies the changes in thermal conductivity, temperature, and unconfined compressive strength of gold tailings and fly ash mixtures during the curing period of 5 days. The microfabric of the cured mixtures was investigated with mercury intrusion porosimetry (MIP). The mixture samples were prepared at their maximum dry unit weight and optimum moisture content. Effect of adding fly ash to gold tailings (i.e., 0, 20, and 40% of the dry weight of tailings) was examined, and a comparison was made on samples prepared at the same fly ash content by replacing gold tailings with humic acid (i.e., gold tailings and humic acid ratios of 100:0, 90:10, and 80:20 by weight) or by varying pore fluid chemistry (i.e., water and salt solutions of 1M NaCl and CaCl2). The results show that the initial thermal conductivity of the samples is sensitive to the mixture proportion and a declination in the thermal conductivity is observed due to hydration of fly ash and evaporation. Inclusion of fly ash and salts into gold tailings improves the unconfined compressive strength but the presence of humic acid in samples leads to the decrease of the strength. MIP results reveal the pore structure changes associated with the packing states of the samples that reflect the influential factors considered. Copyright © 2014 Elsevier B.V. All rights reserved.

Cerebellar inactivation impairs memory of learned prism gaze-reach calibrations.

Science.gov (United States)

Norris, Scott A; Hathaway, Emily N; Taylor, Jordan A; Thach, W Thomas

2011-05-01

Three monkeys performed a visually guided reach-touch task with and without laterally displacing prisms. The prisms offset the normally aligned gaze/reach and subsequent touch. Naive monkeys showed adaptation, such that on repeated prism trials the gaze-reach angle widened and touches hit nearer the target. On the first subsequent no-prism trial the monkeys exhibited an aftereffect, such that the widened gaze-reach angle persisted and touches missed the target in the direction opposite that of initial prism-induced error. After 20-30 days of training, monkeys showed long-term learning and storage of the prism gaze-reach calibration: they switched between prism and no-prism and touched the target on the first trials without adaptation or aftereffect. Injections of lidocaine into posterolateral cerebellar cortex or muscimol or lidocaine into dentate nucleus temporarily inactivated these structures. Immediately after injections into cortex or dentate, reaches were displaced in the direction of prism-displaced gaze, but no-prism reaches were relatively unimpaired. There was little or no adaptation on the day of injection. On days after injection, there was no adaptation and both prism and no-prism reaches were horizontally, and often vertically, displaced. A single permanent lesion (kainic acid) in the lateral dentate nucleus of one monkey immediately impaired only the learned prism gaze-reach calibration and in subsequent days disrupted both learning and performance. This effect persisted for the 18 days of observation, with little or no adaptation.

Right Hemispheric Dominance in Gaze-Triggered Reflexive Shift of Attention in Humans

Science.gov (United States)

Okada, Takashi; Sato, Wataru; Toichi, Motomi

2006-01-01

Recent findings suggest a right hemispheric dominance in gaze-triggered shifts of attention. The aim of this study was to clarify the dominant hemisphere in the gaze processing that mediates attentional shift. A target localization task, with preceding non-predicative gaze cues presented to each visual field, was undertaken by 44 healthy subjects,…

"Gaze Leading": Initiating Simulated Joint Attention Influences Eye Movements and Choice Behavior

Science.gov (United States)

Bayliss, Andrew P.; Murphy, Emily; Naughtin, Claire K.; Kritikos, Ada; Schilbach, Leonhard; Becker, Stefanie I.

2013-01-01

Recent research in adults has made great use of the gaze cuing paradigm to understand the behavior of the follower in joint attention episodes. We implemented a gaze leading task to investigate the initiator--the other person in these triadic interactions. In a series of gaze-contingent eye-tracking studies, we show that fixation dwell time upon…

Rice Husk Ash to Stabilize Heavy Metals Contained in Municipal Solid Waste Incineration Fly Ash: First Results by Applying New Pre-treatment Technology

Directory of Open Access Journals (Sweden)

Laura Benassi

2015-10-01

Full Text Available A new technology was recently developed for municipal solid waste incineration (MSWI fly ash stabilization, based on the employment of all waste and byproduct materials. In particular, the proposed method is based on the use of amorphous silica contained in rice husk ash (RHA, an agricultural byproduct material (COSMOS-RICE project. The obtained final inert can be applied in several applications to produce “green composites”. In this work, for the first time, a process for pre-treatment of rice husk, before its use in the stabilization of heavy metals, based on the employment of Instant Pressure Drop technology (DIC was tested. The aim of this work is to verify the influence of the pre-treatment on the efficiency on heavy metals stabilization in the COSMOS-RICE technology. DIC technique is based on a thermomechanical effect induced by an abrupt transition from high steam pressure to a vacuum, to produce changes in the material. Two different DIC pre-treatments were selected and thermal annealing at different temperatures were performed on rice husk. The resulting RHAs were employed to obtain COSMOS-RICE samples, and the stabilization procedure was tested on the MSWI fly ash. In the frame of this work, some thermal treatments were also realized in O2-limiting conditions, to test the effect of charcoal obtained from RHA on the stabilization procedure. The results of this work show that the application of DIC technology into existing treatment cycles of some waste materials should be investigated in more details to offer the possibility to stabilize and reuse waste.

Rice Husk Ash to Stabilize Heavy Metals Contained in Municipal Solid Waste Incineration Fly Ash: First Results by Applying New Pre-treatment Technology

Science.gov (United States)

Benassi, Laura; Franchi, Federica; Catina, Daniele; Cioffi, Flavio; Rodella, Nicola; Borgese, Laura; Pasquali, Michela; Depero, Laura E.; Bontempi, Elza

2015-01-01

A new technology was recently developed for municipal solid waste incineration (MSWI) fly ash stabilization, based on the employment of all waste and byproduct materials. In particular, the proposed method is based on the use of amorphous silica contained in rice husk ash (RHA), an agricultural byproduct material (COSMOS-RICE project). The obtained final inert can be applied in several applications to produce “green composites”. In this work, for the first time, a process for pre-treatment of rice husk, before its use in the stabilization of heavy metals, based on the employment of Instant Pressure Drop technology (DIC) was tested. The aim of this work is to verify the influence of the pre-treatment on the efficiency on heavy metals stabilization in the COSMOS-RICE technology. DIC technique is based on a thermomechanical effect induced by an abrupt transition from high steam pressure to a vacuum, to produce changes in the material. Two different DIC pre-treatments were selected and thermal annealing at different temperatures were performed on rice husk. The resulting RHAs were employed to obtain COSMOS-RICE samples, and the stabilization procedure was tested on the MSWI fly ash. In the frame of this work, some thermal treatments were also realized in O2-limiting conditions, to test the effect of charcoal obtained from RHA on the stabilization procedure. The results of this work show that the application of DIC technology into existing treatment cycles of some waste materials should be investigated in more details to offer the possibility to stabilize and reuse waste. PMID:28793605

Evaluation of Changes in Index Properties of Lateritic Soil Stabilized with Fly Ash

Directory of Open Access Journals (Sweden)

Agapitus AMADI

2010-12-01

Full Text Available For soils to be suitable in civil engineering projects, they must meet existing local requirements for index properties in addition to certain strength criteria. Typically, specifications limit these properties to some threshold values which in most cases are project specific. Some lateritic soils in their natural state need some treatment/modification to meet these specification requirements. The objective of this study was to evaluate changes in the index properties (i.e., particle size distribution, Atterberg limits and compaction characteristics of a residually derived lateritic soil following fly ash application. Lateritic soil – fly ash mixtures with up to 20% fly ash by dry weight of soil were tested and specimens for compaction characteristics were prepared at different compaction states (optimum, dry and wet of optimum moisture content and compacted using British Standard Light (BSL compactive effort. While soil – fly ash mixtures containing up to 15% fly ash classify as CL according to USCS classification system and plotted above A-line in the plasticity chart, it was observed that changes in the gradation characteristics of soil sample treated with 20% fly ash resulted in the alteration of its classification to ML as well as the crossing of the A- line to the silty region. The liquid limit (LL varied from 42.2 to 29.53% representing 70% reduction while the plasticity index (PI of specimen treated with 20% fly ash was 16% lower than that of natural soil. The optimum moisture content (OMC ranged from 17.36% for the natural soil to 18.34% for soil mixtures containing 20% fly ash which yielded dry unit weight of 17.2kN/m3 for the natural soil and 16.1kN/m3 for samples treated with 20% fly ash. From the study, useful data were obtained showing substantial and desirable changes in the properties of lateritic soil as a civil engineering material on application of fly ash.

Gaze Interactive Building Instructions

DEFF Research Database (Denmark)

Hansen, John Paulin; Ahmed, Zaheer; Mardanbeigi, Diako

We combine eye tracking technology and mobile tablets to support hands-free interaction with digital building instructions. As a proof-of-concept we have developed a small interactive 3D environment where one can interact with digital blocks by gaze, keystroke and head gestures. Blocks may be moved...

Assessing the precision of gaze following using a stereoscopic 3D virtual reality setting.

Science.gov (United States)

Atabaki, Artin; Marciniak, Karolina; Dicke, Peter W; Thier, Peter

2015-07-01

Despite the ecological importance of gaze following, little is known about the underlying neuronal processes, which allow us to extract gaze direction from the geometric features of the eye and head of a conspecific. In order to understand the neuronal mechanisms underlying this ability, a careful description of the capacity and the limitations of gaze following at the behavioral level is needed. Previous studies of gaze following, which relied on naturalistic settings have the disadvantage of allowing only very limited control of potentially relevant visual features guiding gaze following, such as the contrast of iris and sclera, the shape of the eyelids and--in the case of photographs--they lack depth. Hence, in order to get full control of potentially relevant features we decided to study gaze following of human observers guided by the gaze of a human avatar seen stereoscopically. To this end we established a stereoscopic 3D virtual reality setup, in which we tested human subjects' abilities to detect at which target a human avatar was looking at. Following the gaze of the avatar showed all the features of the gaze following of a natural person, namely a substantial degree of precision associated with a consistent pattern of systematic deviations from the target. Poor stereo vision affected performance surprisingly little (only in certain experimental conditions). Only gaze following guided by targets at larger downward eccentricities exhibited a differential effect of the presence or absence of accompanying movements of the avatar's eyelids and eyebrows. Copyright © 2015 Elsevier Ltd. All rights reserved.

Direct gaze elicits atypical activation of the theory-of-mind network in autism spectrum conditions.

Science.gov (United States)

von dem Hagen, Elisabeth A H; Stoyanova, Raliza S; Rowe, James B; Baron-Cohen, Simon; Calder, Andrew J

2014-06-01

Eye contact plays a key role in social interaction and is frequently reported to be atypical in individuals with autism spectrum conditions (ASCs). Despite the importance of direct gaze, previous functional magnetic resonance imaging in ASC has generally focused on paradigms using averted gaze. The current study sought to determine the neural processing of faces displaying direct and averted gaze in 18 males with ASC and 23 matched controls. Controls showed an increased response to direct gaze in brain areas implicated in theory-of-mind and gaze perception, including medial prefrontal cortex, temporoparietal junction, posterior superior temporal sulcus region, and amygdala. In contrast, the same regions showed an increased response to averted gaze in individuals with an ASC. This difference was confirmed by a significant gaze direction × group interaction. Relative to controls, participants with ASC also showed reduced functional connectivity between these regions. We suggest that, in the typical brain, perceiving another person gazing directly at you triggers spontaneous attributions of mental states (e.g. he is "interested" in me), and that such mental state attributions to direct gaze may be reduced or absent in the autistic brain.

EDITORIAL: Special section on gaze-independent brain-computer interfaces Special section on gaze-independent brain-computer interfaces

Science.gov (United States)

Treder, Matthias S.

2012-08-01

Restoring the ability to communicate and interact with the environment in patients with severe motor disabilities is a vision that has been the main catalyst of early brain-computer interface (BCI) research. The past decade has brought a diversification of the field. BCIs have been examined as a tool for motor rehabilitation and their benefit in non-medical applications such as mental-state monitoring for improved human-computer interaction and gaming has been confirmed. At the same time, the weaknesses of some approaches have been pointed out. One of these weaknesses is gaze-dependence, that is, the requirement that the user of a BCI system voluntarily directs his or her eye gaze towards a visual target in order to efficiently operate a BCI. This not only contradicts the main doctrine of BCI research, namely that BCIs should be independent of muscle activity, but it can also limit its real-world applicability both in clinical and non-medical settings. It is only in a scenario devoid of any motor activity that a BCI solution is without alternative. Gaze-dependencies have surfaced at two different points in the BCI loop. Firstly, a BCI that relies on visual stimulation may require users to fixate on the target location. Secondly, feedback is often presented visually, which implies that the user may have to move his or her eyes in order to perceive the feedback. This special section was borne out of a BCI workshop on gaze-independent BCIs held at the 2011 Society for Applied Neurosciences (SAN) Conference and has then been extended with additional contributions from other research groups. It compiles experimental and methodological work that aims toward gaze-independent communication and mental-state monitoring. Riccio et al review the current state-of-the-art in research on gaze-independent BCIs [1]. Van der Waal et al present a tactile speller that builds on the stimulation of the fingers of the right and left hand [2]. H¨ohne et al analyze the ergonomic aspects

Segmentation of object-based video of gaze communication

DEFF Research Database (Denmark)

Aghito, Shankar Manuel; Stegmann, Mikkel Bille; Forchhammer, Søren

2005-01-01

Aspects of video communication based on gaze interaction are considered. The overall idea is to use gaze interaction to control video, e.g. for video conferencing. Towards this goal, animation of a facial mask is demonstrated. The animation is based on images using Active Appearance Models (AAM......). Good quality reproduction of (low-resolution) coded video of an animated facial mask as low as 10-20 kbit/s using MPEG-4 object based video is demonstated....

CULTURAL DISPLAY RULES DRIVE EYE GAZE DURING THINKING.

Science.gov (United States)

McCarthy, Anjanie; Lee, Kang; Itakura, Shoji; Muir, Darwin W

2006-11-01

The authors measured the eye gaze displays of Canadian, Trinidadian, and Japanese participants as they answered questions for which they either knew, or had to derive, the answers. When they knew the answers, Trinidadians maintained the most eye contact, whereas Japanese maintained the least. When thinking about the answers to questions, Canadians and Trinidadians looked up, whereas Japanese looked down. Thus, for humans, gaze displays while thinking are at least in part culturally determined.

Investigating gaze of children with ASD in naturalistic settings.

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Basilio Noris

Full Text Available BACKGROUND: Visual behavior is known to be atypical in Autism Spectrum Disorders (ASD. Monitor-based eye-tracking studies have measured several of these atypicalities in individuals with Autism. While atypical behaviors are known to be accentuated during natural interactions, few studies have been made on gaze behavior in natural interactions. In this study we focused on i whether the findings done in laboratory settings are also visible in a naturalistic interaction; ii whether new atypical elements appear when studying visual behavior across the whole field of view. METHODOLOGY/PRINCIPAL FINDINGS: Ten children with ASD and ten typically developing children participated in a dyadic interaction with an experimenter administering items from the Early Social Communication Scale (ESCS. The children wore a novel head-mounted eye-tracker, measuring gaze direction and presence of faces across the child's field of view. The analysis of gaze episodes to faces revealed that children with ASD looked significantly less and for shorter lapses of time at the experimenter. The analysis of gaze patterns across the child's field of view revealed that children with ASD looked downwards and made more extensive use of their lateral field of view when exploring the environment. CONCLUSIONS/SIGNIFICANCE: The data gathered in naturalistic settings confirm findings previously obtained only in monitor-based studies. Moreover, the study allowed to observe a generalized strategy of lateral gaze in children with ASD when they were looking at the objects in their environment.

Model-driven gaze simulation for the blind person in face-to-face communication

NARCIS (Netherlands)

Qiu, S.; Anas, S.A.B.; Osawa, H.; Rauterberg, G.W.M.; Hu, J.

2016-01-01

In face-to-face communication, eye gaze is integral to a conversation to supplement verbal language. The sighted often uses eye gaze to convey nonverbal information in social interactions, which a blind conversation partner cannot access and react to them. In this paper, we present E-Gaze glasses

P2-23: Deficits on Preference but Not Attention in Patients with Depression: Evidence from Gaze Cue

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Jingling Li

2012-10-01

Full Text Available Gaze is an important social cue and can easily capture attention. Our preference judgment is biased by others' gaze; that is, we prefer objects gazed by happy or neutral faces and dislike objects gazed by disgust faces. Since patients with depression have a negative bias in emotional perception, we hypothesized that they may have different preference judgment on the gazed objects than healthy controls. Twenty-one patients with major depressive disorder and 21 healthy age-matched controls completed an object categorization task and then rated their preference on those objects. In the categorization task, a schematic face either gazed toward or away from the to-be-categorized object. The results showed that both groups categorized faster for gazed objects than non-gazed objects, suggesting that patients did not have deficits on their attention to gaze cues. Nevertheless, healthy controls preferred gazed objects more than non-gazed objects, while patients did not have significant preference. Our result indicated that patients with depression have deficits on their social cognition rather than basic attentional mechanism.

APC fly ashes stabilized with Portland cement for further development of road sub-base aggregates

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Formosa, J.; Giro-Paloma, J.; Maldonado-Alameda, A.; Huete-Hernández, S.; Chimenos, J. M.

2017-10-01

Although waste-to-energy plants allow reducing the mass and volume of municipal solid waste (MSW) incinerated, an average around 30 % of the total content remains as bottom ash (BA) and air pollution control (APC) ashes at the end of combustion process. While weathered bottom ash (WBA) is considered a non-hazardous residue that can be revalorized as a secondary aggregate, APC fly ashes generated during the flue gas treatment are classified as hazardous waste and are handled in landfill disposal after stabilization, usually with Portland cement (OPC). However, taking into account the amount of APC residues produced and the disposing cost in landfill, their revalorization is an important issue that could be effectively addressed. As MSW can be incinerated producing bottom ashes (BA) or air pollutant control (APC) residues, the development of a mortar formulated with APC fly ash as secondary building material is a significant risk to the environment for their content of heavy metals. In this way, Design of Experiment (DoE) was used for the improvement of granular material (GM) formulation composed by APC and OPC for further uses as road sub-base aggregate. DoE analysis was successful in the modelling and optimization the formulation as function of the mechanical properties and APC amount. Consequently, an optimal mortar formulation (OMF) of around 50 wt.% APC and 50 wt.% OPC was considered. The OMF leachates and abrasion resistance have been analyzed. These results have demonstrated the viability of OMF as non-hazardous material feasible to be used as secondary aggregate. Moreover, it would be possible to consider the environmental assessment of a GM composed by ≈20 wt.% of OMF and ≈80 wt.% of WBA in order to improve mechanical properties and heavy metals stabilization.

The Role of Global and Local Visual Information during Gaze-Cued Orienting of Attention.

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Munsters, Nicolette M; van den Boomen, Carlijn; Hooge, Ignace T C; Kemner, Chantal

2016-01-01

Gaze direction is an important social communication tool. Global and local visual information are known to play specific roles in processing socially relevant information from a face. The current study investigated whether global visual information has a primary role during gaze-cued orienting of attention and, as such, may influence quality of interaction. Adults performed a gaze-cueing task in which a centrally presented face cued (valid or invalid) the location of a peripheral target through a gaze shift. We measured brain activity (electroencephalography) towards the cue and target and behavioral responses (manual and saccadic reaction times) towards the target. The faces contained global (i.e. lower spatial frequencies), local (i.e. higher spatial frequencies), or a selection of both global and local (i.e. mid-band spatial frequencies) visual information. We found a gaze cue-validity effect (i.e. valid versus invalid), but no interaction effects with spatial frequency content. Furthermore, behavioral responses towards the target were in all cue conditions slower when lower spatial frequencies were not present in the gaze cue. These results suggest that whereas gaze-cued orienting of attention can be driven by both global and local visual information, global visual information determines the speed of behavioral responses towards other entities appearing in the surrounding of gaze cue stimuli.

Fusing Eye-gaze and Speech Recognition for Tracking in an Automatic Reading Tutor

DEFF Research Database (Denmark)

Rasmussen, Morten Højfeldt; Tan, Zheng-Hua

2013-01-01

In this paper we present a novel approach for automatically tracking the reading progress using a combination of eye-gaze tracking and speech recognition. The two are fused by first generating word probabilities based on eye-gaze information and then using these probabilities to augment the langu......In this paper we present a novel approach for automatically tracking the reading progress using a combination of eye-gaze tracking and speech recognition. The two are fused by first generating word probabilities based on eye-gaze information and then using these probabilities to augment...

A closer look at the size of the gaze-liking effect: a preregistered replication.

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Tipples, Jason; Pecchinenda, Anna

2018-04-30

This study is a direct replication of gaze-liking effect using the same design, stimuli and procedure. The gaze-liking effect describes the tendency for people to rate objects as more likeable when they have recently seen a person repeatedly gaze toward rather than away from the object. However, as subsequent studies show considerable variability in the size of this effect, we sampled a larger number of participants (N = 98) than the original study (N = 24) to gain a more precise estimate of the gaze-liking effect size. Our results indicate a much smaller standardised effect size (d z  = 0.02) than that of the original study (d z  = 0.94). Our smaller effect size was not due to general insensitivity to eye-gaze effects because the same sample showed a clear (d z  = 1.09) gaze-cuing effect - faster reaction times when eyes looked toward vs away from target objects. We discuss the implications of our findings for future studies wishing to study the gaze-liking effect.

Role of Gaze Cues in Interpersonal Motor Coordination: Towards Higher Affiliation in Human-Robot Interaction.

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Mahdi Khoramshahi

Full Text Available The ability to follow one another's gaze plays an important role in our social cognition; especially when we synchronously perform tasks together. We investigate how gaze cues can improve performance in a simple coordination task (i.e., the mirror game, whereby two players mirror each other's hand motions. In this game, each player is either a leader or follower. To study the effect of gaze in a systematic manner, the leader's role is played by a robotic avatar. We contrast two conditions, in which the avatar provides or not explicit gaze cues that indicate the next location of its hand. Specifically, we investigated (a whether participants are able to exploit these gaze cues to improve their coordination, (b how gaze cues affect action prediction and temporal coordination, and (c whether introducing active gaze behavior for avatars makes them more realistic and human-like (from the user point of view.43 subjects participated in 8 trials of the mirror game. Each subject performed the game in the two conditions (with and without gaze cues. In this within-subject study, the order of the conditions was randomized across participants, and subjective assessment of the avatar's realism was assessed by administering a post-hoc questionnaire. When gaze cues were provided, a quantitative assessment of synchrony between participants and the avatar revealed a significant improvement in subject reaction-time (RT. This confirms our hypothesis that gaze cues improve the follower's ability to predict the avatar's action. An analysis of the pattern of frequency across the two players' hand movements reveals that the gaze cues improve the overall temporal coordination across the two players. Finally, analysis of the subjective evaluations from the questionnaires reveals that, in the presence of gaze cues, participants found it not only more human-like/realistic, but also easier to interact with the avatar.This work confirms that people can exploit gaze cues to

Dysfunctional gaze processing in bipolar disorder

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Cristina Berchio

2017-01-01

The present study provides neurophysiological evidence for abnormal gaze processing in BP and suggests dysfunctional processing of direct eye contact as a prominent characteristic of bipolar disorder.

Gaze strategies during visually-guided versus memory-guided grasping.

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Prime, Steven L; Marotta, Jonathan J

2013-03-01

Vision plays a crucial role in guiding motor actions. But sometimes we cannot use vision and must rely on our memory to guide action-e.g. remembering where we placed our eyeglasses on the bedside table when reaching for them with the lights off. Recent studies show subjects look towards the index finger grasp position during visually-guided precision grasping. But, where do people look during memory-guided grasping? Here, we explored the gaze behaviour of subjects as they grasped a centrally placed symmetrical block under open- and closed-loop conditions. In Experiment 1, subjects performed grasps in either a visually-guided task or memory-guided task. The results show that during visually-guided grasping, gaze was first directed towards the index finger's grasp point on the block, suggesting gaze targets future grasp points during the planning of the grasp. Gaze during memory-guided grasping was aimed closer to the blocks' centre of mass from block presentation to the completion of the grasp. In Experiment 2, subjects performed an 'immediate grasping' task in which vision of the block was removed immediately at the onset of the reach. Similar to the visually-guided results from Experiment 1, gaze was primarily directed towards the index finger location. These results support the 2-stream theory of vision in that motor planning with visual feedback at the onset of the movement is driven primarily by real-time visuomotor computations of the dorsal stream, whereas grasping remembered objects without visual feedback is driven primarily by the perceptual memory representations mediated by the ventral stream.

Flexible coordination of stationary and mobile conversations with gaze: Resource allocation among multiple joint activities

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Eric Mayor

2016-10-01

Full Text Available Gaze is instrumental in coordinating face-to-face social interactions. But little is known about gaze use when social interactions co-occur with other joint activities. We investigated the case of walking while talking. We assessed how gaze gets allocated among various targets in mobile conversations, whether allocation of gaze to other targets affects conversational coordination, and whether reduced availability of gaze for conversational coordination affects conversational performance and content. In an experimental study, pairs were videotaped in four conditions of mobility (standing still, talking while walking along a straight-line itinerary, talking while walking along a complex itinerary, or walking along a complex itinerary with no conversational task. Gaze to partners was substantially reduced in mobile conversations, but gaze was still used to coordinate conversation via displays of mutual orientation, and conversational performance and content was not different between stationary and mobile conditions. Results expand the phenomena of multitasking to joint activities.

Gaze direction effects on perceptions of upper limb kinesthetic coordinate system axes.

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Darling, W G; Hondzinski, J M; Harper, J G

2000-12-01

The effects of varying gaze direction on perceptions of the upper limb kinesthetic coordinate system axes and of the median plane location were studied in nine subjects with no history of neuromuscular disorders. In two experiments, six subjects aligned the unseen forearm to the trunk-fixed anterior-posterior (a/p) axis and earth-fixed vertical while gazing at different visual targets using either head or eye motion to vary gaze direction in different conditions. Effects of support of the upper limb on perceptual errors were also tested in different conditions. Absolute constant errors and variable errors associated with forearm alignment to the trunk-fixed a/p axis and earth-fixed vertical were similar for different gaze directions whether the head or eyes were moved to control gaze direction. Such errors were decreased by support of the upper limb when aligning to the vertical but not when aligning to the a/p axis. Regression analysis showed that single trial errors in individual subjects were poorly correlated with gaze direction, but showed a dependence on shoulder angles for alignment to both axes. Thus, changes in position of the head and eyes do not influence perceptions of upper limb kinesthetic coordinate system axes. However, dependence of the errors on arm configuration suggests that such perceptions are generated from sensations of shoulder and elbow joint angle information. In a third experiment, perceptions of median plane location were tested by instructing four subjects to place the unseen right index fingertip directly in front of the sternum either by motion of the straight arm at the shoulder or by elbow flexion/extension with shoulder angle varied. Gaze angles were varied to the right and left by 0.5 radians to determine effects of gaze direction on such perceptions. These tasks were also carried out with subjects blind-folded and head orientation varied to test for effects of head orientation on perceptions of median plane location. Constant

Closed-loop response properties of a visual interneuron involved in fly optomotor control

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Naveed eEjaz

2013-03-01

Full Text Available Due to methodological limitations neural function is mostly studied under open-loop conditions. Normally, however, nervous systems operate in closed-loop where sensory input is processed to generate behavioural outputs, which again change the sensory input. Here, we investigate the closed-loop responses of an identified visual interneuron, the blowfly H1-cell, that is part of a neural circuit involved in optomotor flight and gaze control. Those behaviours may be triggered by attitude changes during flight in turbulent air. The fly analyses the resulting retinal image shifts and performs compensatory body and head rotations to regain its default attitude. We developed a fly-robot interface to study H1-cell responses in a 1 degree-of-freedom image stabilization task. Image shifts, induced by externally forced rotations, modulate the cell’s spike rate that controls counter rotations of a mobile robot to minimize relative motion between the robot and its visual surroundings. A feedback controller closed the loop between neural activity and the rotation of the robot. Under these conditions we found the following H1-cell response properties: (i the peak spike rate decreases when the mean image velocity is increased, (ii the relationship between spike rate and image velocity depends on the standard deviation of the image velocities suggesting adaptive scaling of the cell’s signalling range, and (iii the cell’s gain decreases linearly with increasing image accelerations.Our results reveal a remarkable qualitative similarity between the response dynamics of the H1-cell under closed-loop conditions with those obtained in previous open-loop experiments. Finally, we show that the adaptive scaling of the H1-cell’s responses, while maximizing information on image velocity, decreases the cell’s sensitivity to image accelerations. Understanding such trade-offs in biological vision systems may advance the design of smart vision sensors for autonomous

Suppressing Heavy Metal Leaching through Ball Milling of Fly Ash

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Zhiliang Chen

2016-07-01

Full Text Available Ball milling is investigated as a method of reducing the leaching concentration (often termed stablilization of heavy metals in municipal solid waste incineration (MSWI fly ash. Three heavy metals (Cu, Cr, Pb loose much of their solubility in leachate by treating fly ash in a planetary ball mill, in which collisions between balls and fly ash drive various physical processes, as well as chemical reactions. The efficiency of stabilization is evaluated by analysing heavy metals in the leachable fraction from treated fly ash. Ball milling reduces the leaching concentration of Cu, Cr, and Pb, and water washing effectively promotes stabilization efficiency by removing soluble salts. Size distribution and morphology of particles were analysed by laser particle diameter analysis and scanning electron microscopy. X-ray diffraction analysis reveals significant reduction of the crystallinity of fly ash by milling. Fly ash particles can be activated through this ball milling, leading to a significant decrease in particle size, a rise in its BET-surface, and turning basic crystals therein into amorphous structures. The dissolution rate of acid buffering materials present in activated particles is enhanced, resulting in a rising pH value of the leachate, reducing the leaching out of some heavy metals.

The Eyes Are the Windows to the Mind: Direct Eye Gaze Triggers the Ascription of Others' Minds.

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Khalid, Saara; Deska, Jason C; Hugenberg, Kurt

2016-12-01

Eye gaze is a potent source of social information with direct eye gaze signaling the desire to approach and averted eye gaze signaling avoidance. In the current work, we proposed that eye gaze signals whether or not to impute minds into others. Across four studies, we manipulated targets' eye gaze (i.e., direct vs. averted eye gaze) and measured explicit mind ascriptions (Study 1a, Study 1b, and Study 2) and beliefs about the likelihood of targets having mind (Study 3). In all four studies, we find novel evidence that the ascription of sophisticated humanlike minds to others is signaled by the display of direct eye gaze relative to averted eye gaze. Moreover, we provide evidence suggesting that this differential mentalization is due, at least in part, to beliefs that direct gaze targets are more likely to instigate social interaction. In short, eye contact triggers mind perception. © 2016 by the Society for Personality and Social Psychology, Inc.

Gaze training enhances laparoscopic technical skill acquisition and multi-tasking performance: a randomized, controlled study.

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Wilson, Mark R; Vine, Samuel J; Bright, Elizabeth; Masters, Rich S W; Defriend, David; McGrath, John S

2011-12-01

The operating room environment is replete with stressors and distractions that increase the attention demands of what are already complex psychomotor procedures. Contemporary research in other fields (e.g., sport) has revealed that gaze training interventions may support the development of robust movement skills. This current study was designed to examine the utility of gaze training for technical laparoscopic skills and to test performance under multitasking conditions. Thirty medical trainees with no laparoscopic experience were divided randomly into one of three treatment groups: gaze trained (GAZE), movement trained (MOVE), and discovery learning/control (DISCOVERY). Participants were fitted with a Mobile Eye gaze registration system, which measures eye-line of gaze at 25 Hz. Training consisted of ten repetitions of the "eye-hand coordination" task from the LAP Mentor VR laparoscopic surgical simulator while receiving instruction and video feedback (specific to each treatment condition). After training, all participants completed a control test (designed to assess learning) and a multitasking transfer test, in which they completed the procedure while performing a concurrent tone counting task. Not only did the GAZE group learn more quickly than the MOVE and DISCOVERY groups (faster completion times in the control test), but the performance difference was even more pronounced when multitasking. Differences in gaze control (target locking fixations), rather than tool movement measures (tool path length), underpinned this performance advantage for GAZE training. These results suggest that although the GAZE intervention focused on training gaze behavior only, there were indirect benefits for movement behaviors and performance efficiency. Additionally, focusing on a single external target when learning, rather than on complex movement patterns, may have freed-up attentional resources that could be applied to concurrent cognitive tasks.

Towards gaze-controlled platform games

DEFF Research Database (Denmark)

Muñoz, Jorge; Yannakakis, Georgios N.; Mulvey, Fiona

2011-01-01

This paper introduces the concept of using gaze as a sole modality for fully controlling player characters of fast-paced action computer games. A user experiment is devised to collect gaze and gameplay data from subjects playing a version of the popular Super Mario Bros platform game. The initial...... analysis shows that there is a rather limited grid around Mario where the efficient player focuses her attention the most while playing the game. The useful grid as we name it, projects the amount of meaningful visual information a designer should use towards creating successful player character...... controllers with the use of artificial intelligence for a platform game like Super Mario. Information about the eyes' position on the screen and the state of the game are utilized as inputs of an artificial neural network, which is trained to approximate which keyboard action is to be performed at each game...

Gaze recognition in high-functioning autistic patients. Evidence from functional MRI

International Nuclear Information System (INIS)

Takebayashi, Hiroko; Ogai, Masahiro; Matsumoto, Hideo

2006-01-01

We examined whether patients with high-functioning autistic disorder (AD) would exhibit abnormal activation in brain regions implicated in the functioning of theory of mind (TOM) during gaze recognition. We investigated brain activity during gaze recognition in 5 patients with high-functioning AD and 9 normal subjects, using functional magnetic resonance imaging. On the gaze task, more activation was found in the left middle frontal gyrus, the right intraparietal sulcus, and the precentral and inferior parietal gyri bilaterally in controls than in AD patients, whereas the patient group showed more powerful signal changes in the left superior temporal gyrus, the right insula, and the right medial frontal gyrus. These results suggest that high-functioning AD patients have functional abnormalities not only in TOM-related brain regions, but also in widely distributed brain regions that are not normally activated upon the processing of information from another person's gaze. (author)

A neural-based remote eye gaze tracker under natural head motion.

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Torricelli, Diego; Conforto, Silvia; Schmid, Maurizio; D'Alessio, Tommaso

2008-10-01

A novel approach to view-based eye gaze tracking for human computer interface (HCI) is presented. The proposed method combines different techniques to address the problems of head motion, illumination and usability in the framework of low cost applications. Feature detection and tracking algorithms have been designed to obtain an automatic setup and strengthen the robustness to light conditions. An extensive analysis of neural solutions has been performed to deal with the non-linearity associated with gaze mapping under free-head conditions. No specific hardware, such as infrared illumination or high-resolution cameras, is needed, rather a simple commercial webcam working in visible light spectrum suffices. The system is able to classify the gaze direction of the user over a 15-zone graphical interface, with a success rate of 95% and a global accuracy of around 2 degrees , comparable with the vast majority of existing remote gaze trackers.

Clinician's gaze behaviour in simulated paediatric emergencies.

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McNaughten, Ben; Hart, Caroline; Gallagher, Stephen; Junk, Carol; Coulter, Patricia; Thompson, Andrew; Bourke, Thomas

2018-03-07

Differences in the gaze behaviour of experts and novices are described in aviation and surgery. This study sought to describe the gaze behaviour of clinicians from different training backgrounds during a simulated paediatric emergency. Clinicians from four clinical areas undertook a simulated emergency. Participants wore SMI (SensoMotoric Instruments) eye tracking glasses. We measured the fixation count and dwell time on predefined areas of interest and the time taken to key clinical interventions. Paediatric intensive care unit (PICU) consultants performed best and focused longer on the chest and airway. Paediatric consultants and trainees spent longer looking at the defibrillator and algorithm (51 180 ms and 50 551 ms, respectively) than the PICU and paediatric emergency medicine consultants. This study is the first to describe differences in the gaze behaviour between experts and novices in a resuscitation. They mirror those described in aviation and surgery. Further research is needed to evaluate the potential use of eye tracking as an educational tool. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Measurement of Flying Qualities of a Dehavilland Mosquito F-8 Airplane (AAF No. 43-334960) I: Lateral and Directional Stability and Control Characteristics

Science.gov (United States)

Gray, W.E.; Talmage, D.B.; Crane, H.L.

1945-01-01

The data presented have no bearing on performance characteristics of airplane, which were considered exceptionally good in previous tests. Some of the undesirable features of lateral and directional stability and control characteristics of the F-8 are listed. Directional stability, with rudder fixed, did not sufficiently restrict aileron yaw; rudder control was inadequate during take-off and landing, and was insufficient to fly airplane with one engine; in clean condition, power of ailerons was slightly below minimum value specified; it was difficult to trim airplane in rough air.

Social evolution. Oxytocin-gaze positive loop and the coevolution of human-dog bonds.

Science.gov (United States)

Nagasawa, Miho; Mitsui, Shouhei; En, Shiori; Ohtani, Nobuyo; Ohta, Mitsuaki; Sakuma, Yasuo; Onaka, Tatsushi; Mogi, Kazutaka; Kikusui, Takefumi

2015-04-17

Human-like modes of communication, including mutual gaze, in dogs may have been acquired during domestication with humans. We show that gazing behavior from dogs, but not wolves, increased urinary oxytocin concentrations in owners, which consequently facilitated owners' affiliation and increased oxytocin concentration in dogs. Further, nasally administered oxytocin increased gazing behavior in dogs, which in turn increased urinary oxytocin concentrations in owners. These findings support the existence of an interspecies oxytocin-mediated positive loop facilitated and modulated by gazing, which may have supported the coevolution of human-dog bonding by engaging common modes of communicating social attachment. Copyright © 2015, American Association for the Advancement of Science.

Between Gazes

DEFF Research Database (Denmark)

Elias, Camelia

2009-01-01

In the film documentary Zizek! (2006) Astra Taylor, the film’s director, introduces Slavoj Zizek and his central notions of Lacanian psychoanalysis as they tie in with Marxism, ideology, and culture. Apart from following Zizek from New York to his home in Ljubljana, the documentary presents...... delivers his thoughts on philosophy while in bed or in the bathroom. It is clear that one of the devices that the documentary uses in its portrayal of Zizek is the palimpsest, and what is being layered is the gaze. My essay introduces the idea of layering as a case of intermediality between different art...

Deep Learning-Based Gaze Detection System for Automobile Drivers Using a NIR Camera Sensor.

Science.gov (United States)

Naqvi, Rizwan Ali; Arsalan, Muhammad; Batchuluun, Ganbayar; Yoon, Hyo Sik; Park, Kang Ryoung

2018-02-03

A paradigm shift is required to prevent the increasing automobile accident deaths that are mostly due to the inattentive behavior of drivers. Knowledge of gaze region can provide valuable information regarding a driver's point of attention. Accurate and inexpensive gaze classification systems in cars can improve safe driving. However, monitoring real-time driving behaviors and conditions presents some challenges: dizziness due to long drives, extreme lighting variations, glasses reflections, and occlusions. Past studies on gaze detection in cars have been chiefly based on head movements. The margin of error in gaze detection increases when drivers gaze at objects by moving their eyes without moving their heads. To solve this problem, a pupil center corneal reflection (PCCR)-based method has been considered. However, the error of accurately detecting the pupil center and corneal reflection center is increased in a car environment due to various environment light changes, reflections on glasses surface, and motion and optical blurring of captured eye image. In addition, existing PCCR-based methods require initial user calibration, which is difficult to perform in a car environment. To address this issue, we propose a deep learning-based gaze detection method using a near-infrared (NIR) camera sensor considering driver head and eye movement that does not require any initial user calibration. The proposed system is evaluated on our self-constructed database as well as on open Columbia gaze dataset (CAVE-DB). The proposed method demonstrated greater accuracy than the previous gaze classification methods.

Race perception and gaze direction differently impair visual working memory for faces: An event-related potential study.

Science.gov (United States)

Sessa, Paola; Dalmaso, Mario

2016-01-01

Humans are amazingly experts at processing and recognizing faces, however there are moderating factors of this ability. In the present study, we used the event-related potential technique to investigate the influence of both race and gaze direction on visual working memory (i.e., VWM) face representations. In a change detection task, we orthogonally manipulated race (own-race vs. other-race faces) and eye-gaze direction (direct gaze vs. averted gaze). Participants were required to encode identities of these faces. We quantified the amount of information encoded in VWM by monitoring the amplitude of the sustained posterior contralateral negativity (SPCN) time-locked to the faces. Notably, race and eye-gaze direction differently modulated SPCN amplitude such that other-race faces elicited reduced SPCN amplitudes compared with own-race faces only when displaying a direct gaze. On the other hand, faces displaying averted gaze, independently of their race, elicited increased SPCN amplitudes compared with faces displaying direct gaze. We interpret these findings as denoting that race and eye-gaze direction affect different face processing stages.

Aversive eye gaze during a speech in virtual environment in patients with social anxiety disorder.

Science.gov (United States)

Kim, Haena; Shin, Jung Eun; Hong, Yeon-Ju; Shin, Yu-Bin; Shin, Young Seok; Han, Kiwan; Kim, Jae-Jin; Choi, Soo-Hee

2018-03-01

One of the main characteristics of social anxiety disorder is excessive fear of social evaluation. In such situations, anxiety can influence gaze behaviour. Thus, the current study adopted virtual reality to examine eye gaze pattern of social anxiety disorder patients while presenting different types of speeches. A total of 79 social anxiety disorder patients and 51 healthy controls presented prepared speeches on general topics and impromptu speeches on self-related topics to a virtual audience while their eye gaze was recorded. Their presentation performance was also evaluated. Overall, social anxiety disorder patients showed less eye gaze towards the audience than healthy controls. Types of speech did not influence social anxiety disorder patients' gaze allocation towards the audience. However, patients with social anxiety disorder showed significant correlations between the amount of eye gaze towards the audience while presenting self-related speeches and social anxiety cognitions. The current study confirms that eye gaze behaviour of social anxiety disorder patients is aversive and that their anxiety symptoms are more dependent on the nature of topic.

Gaze Step Distributions Reflect Fixations and Saccades: A Comment on Stephen and Mirman (2010)

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Bogartz, Richard S.; Staub, Adrian

2012-01-01

In three experimental tasks Stephen and Mirman (2010) measured gaze steps, the distance in pixels between gaze positions on successive samples from an eyetracker. They argued that the distribution of gaze steps is best fit by the lognormal distribution, and based on this analysis they concluded that interactive cognitive processes underlie eye…

Gaze-Contingent Music Reward Therapy for Social Anxiety Disorder: A Randomized Controlled Trial.

Science.gov (United States)

Lazarov, Amit; Pine, Daniel S; Bar-Haim, Yair

2017-07-01

Patients with social anxiety disorder exhibit increased attentional dwelling on social threats, providing a viable target for therapeutics. This randomized controlled trial examined the efficacy of a novel gaze-contingent music reward therapy for social anxiety disorder designed to reduce attention dwelling on threats. Forty patients with social anxiety disorder were randomly assigned to eight sessions of either gaze-contingent music reward therapy, designed to divert patients' gaze toward neutral stimuli rather than threat stimuli, or to a control condition. Clinician and self-report measures of social anxiety were acquired pretreatment, posttreatment, and at 3-month follow-up. Dwell time on socially threatening faces was assessed during the training sessions and at pre- and posttreatment. Gaze-contingent music reward therapy yielded greater reductions of symptoms of social anxiety disorder than the control condition on both clinician-rated and self-reported measures. Therapeutic effects were maintained at follow-up. Gaze-contingent music reward therapy, but not the control condition, also reduced dwell time on threat, which partially mediated clinical effects. Finally, gaze-contingent music reward therapy, but not the control condition, also altered dwell time on socially threatening faces not used in training, reflecting near-transfer training generalization. This is the first randomized controlled trial to examine a gaze-contingent intervention in social anxiety disorder. The results demonstrate target engagement and clinical effects. This study sets the stage for larger randomized controlled trials and testing in other emotional disorders.

Stabilization of lead in an alkali-activated municipal solid waste incineration fly ash-Pyrophyllite-based system.

Science.gov (United States)

Shiota, Kenji; Nakamura, Takafumi; Takaoka, Masaki; Aminuddin, Siti Fatimah; Oshita, Kazuyuki; Fujimori, Takashi

2017-10-01

This work focuses on the stabilization and speciation of lead (Pb) in a composite solid produced from an alkali-activated municipal solid waste incineration fly ash (MSWIFA)-pyophyllite-based system. The solid product was synthesized after mixtures of raw materials (dehydrated pyrophyllite, MSWIFA, 14 mol/L aqueous sodium hydroxide, and sodium silicate solution) were cured at 105 °C for 24 h. The product could reduce the leaching of Pb and the Pb concentration in the leachate was 7.0 × 10 -3 using the Japanese leaching test and 9.7 × 10 -4  mg/L using toxicity characteristics leaching procedure method, which satisfied the respective test criteria and successfully stabilized Pb in this system. The solid product had a compressive strength of 2 MPa and consisted mainly of crystalline phases. Scanning electron microscopy with X-ray analysis and X-ray absorption fine structure suggested that Pb was present along with Al, Si, and O, and that the atomic environment around the Pb was similar to that of PbSiO 3 . These results suggest that the alkali-activated MSWIFA-pyrophyllite-based system could be used to stabilize Pb in MSWIFA. Copyright © 2017 Elsevier Ltd. All rights reserved.

Gaze-based assistive technology in daily activities in children with severe physical impairments-An intervention study.

Science.gov (United States)

Borgestig, Maria; Sandqvist, Jan; Ahlsten, Gunnar; Falkmer, Torbjörn; Hemmingsson, Helena

2017-04-01

To establish the impact of a gaze-based assistive technology (AT) intervention on activity repertoire, autonomous use, and goal attainment in children with severe physical impairments, and to examine parents' satisfaction with the gaze-based AT and with services related to the gaze-based AT intervention. Non-experimental multiple case study with before, after, and follow-up design. Ten children with severe physical impairments without speaking ability (aged 1-15 years) participated in gaze-based AT intervention for 9-10 months, during which period the gaze-based AT was implemented in daily activities. Repertoire of computer activities increased for seven children. All children had sustained usage of gaze-based AT in daily activities at follow-up, all had attained goals, and parents' satisfaction with the AT and with services was high. The gaze-based AT intervention was effective in guiding parents and teachers to continue supporting the children to perform activities with the AT after the intervention program.

Gaze Shift as an Interactional Resource for Very Young Children

Science.gov (United States)

Kidwell, Mardi

2009-01-01

This article examines how very young children in a day care center make use of their peers' gaze shifts to differentially locate and prepare for the possibility of a caregiver intervention during situations of their biting, hitting, pushing, and the like. At issue is how the visible character of a gaze shift--that is, the manner in which it is…

Deep Learning-Based Gaze Detection System for Automobile Drivers Using a NIR Camera Sensor

Directory of Open Access Journals (Sweden)

Rizwan Ali Naqvi

2018-02-01

Full Text Available A paradigm shift is required to prevent the increasing automobile accident deaths that are mostly due to the inattentive behavior of drivers. Knowledge of gaze region can provide valuable information regarding a driver’s point of attention. Accurate and inexpensive gaze classification systems in cars can improve safe driving. However, monitoring real-time driving behaviors and conditions presents some challenges: dizziness due to long drives, extreme lighting variations, glasses reflections, and occlusions. Past studies on gaze detection in cars have been chiefly based on head movements. The margin of error in gaze detection increases when drivers gaze at objects by moving their eyes without moving their heads. To solve this problem, a pupil center corneal reflection (PCCR-based method has been considered. However, the error of accurately detecting the pupil center and corneal reflection center is increased in a car environment due to various environment light changes, reflections on glasses surface, and motion and optical blurring of captured eye image. In addition, existing PCCR-based methods require initial user calibration, which is difficult to perform in a car environment. To address this issue, we propose a deep learning-based gaze detection method using a near-infrared (NIR camera sensor considering driver head and eye movement that does not require any initial user calibration. The proposed system is evaluated on our self-constructed database as well as on open Columbia gaze dataset (CAVE-DB. The proposed method demonstrated greater accuracy than the previous gaze classification methods.

iShadow: Design of a Wearable, Real-Time Mobile Gaze Tracker.

Science.gov (United States)

Mayberry, Addison; Hu, Pan; Marlin, Benjamin; Salthouse, Christopher; Ganesan, Deepak

2014-06-01

Continuous, real-time tracking of eye gaze is valuable in a variety of scenarios including hands-free interaction with the physical world, detection of unsafe behaviors, leveraging visual context for advertising, life logging, and others. While eye tracking is commonly used in clinical trials and user studies, it has not bridged the gap to everyday consumer use. The challenge is that a real-time eye tracker is a power-hungry and computation-intensive device which requires continuous sensing of the eye using an imager running at many tens of frames per second, and continuous processing of the image stream using sophisticated gaze estimation algorithms. Our key contribution is the design of an eye tracker that dramatically reduces the sensing and computation needs for eye tracking, thereby achieving orders of magnitude reductions in power consumption and form-factor. The key idea is that eye images are extremely redundant, therefore we can estimate gaze by using a small subset of carefully chosen pixels per frame. We instantiate this idea in a prototype hardware platform equipped with a low-power image sensor that provides random access to pixel values, a low-power ARM Cortex M3 microcontroller, and a bluetooth radio to communicate with a mobile phone. The sparse pixel-based gaze estimation algorithm is a multi-layer neural network learned using a state-of-the-art sparsity-inducing regularization function that minimizes the gaze prediction error while simultaneously minimizing the number of pixels used. Our results show that we can operate at roughly 70mW of power, while continuously estimating eye gaze at the rate of 30 Hz with errors of roughly 3 degrees.

iShadow: Design of a Wearable, Real-Time Mobile Gaze Tracker

Science.gov (United States)

Mayberry, Addison; Hu, Pan; Marlin, Benjamin; Salthouse, Christopher; Ganesan, Deepak

2015-01-01

Continuous, real-time tracking of eye gaze is valuable in a variety of scenarios including hands-free interaction with the physical world, detection of unsafe behaviors, leveraging visual context for advertising, life logging, and others. While eye tracking is commonly used in clinical trials and user studies, it has not bridged the gap to everyday consumer use. The challenge is that a real-time eye tracker is a power-hungry and computation-intensive device which requires continuous sensing of the eye using an imager running at many tens of frames per second, and continuous processing of the image stream using sophisticated gaze estimation algorithms. Our key contribution is the design of an eye tracker that dramatically reduces the sensing and computation needs for eye tracking, thereby achieving orders of magnitude reductions in power consumption and form-factor. The key idea is that eye images are extremely redundant, therefore we can estimate gaze by using a small subset of carefully chosen pixels per frame. We instantiate this idea in a prototype hardware platform equipped with a low-power image sensor that provides random access to pixel values, a low-power ARM Cortex M3 microcontroller, and a bluetooth radio to communicate with a mobile phone. The sparse pixel-based gaze estimation algorithm is a multi-layer neural network learned using a state-of-the-art sparsity-inducing regularization function that minimizes the gaze prediction error while simultaneously minimizing the number of pixels used. Our results show that we can operate at roughly 70mW of power, while continuously estimating eye gaze at the rate of 30 Hz with errors of roughly 3 degrees. PMID:26539565

Investigating gaze-controlled input in a cognitive selection test

OpenAIRE

Gayraud, Katja; Hasse, Catrin; Eißfeldt, Hinnerk; Pannasch, Sebastian

2017-01-01

In the field of aviation, there is a growing interest in developing more natural forms of interaction between operators and systems to enhance safety and efficiency. These efforts also include eye gaze as an input channel for human-machine interaction. The present study investigates the application of gaze-controlled input in a cognitive selection test called Eye Movement Conflict Detection Test. The test enables eye movements to be studied as an indicator for psychological test performance a...

Gaze-based interaction with public displays using off-the-shelf components

DEFF Research Database (Denmark)

San Agustin, Javier; Hansen, John Paulin; Tall, Martin Henrik

Eye gaze can be used to interact with high-density information presented on large displays. We have built a system employing off-the-shelf hardware components and open-source gaze tracking software that enables users to interact with an interface displayed on a 55” screen using their eye movement...

Gaze Strategies in Skateboard Trick Jumps: Spatiotemporal Constraints in Complex Locomotion

Science.gov (United States)

Klostermann, André; Küng, Philip

2017-01-01

Purpose: This study aimed to further the knowledge on gaze behavior in locomotion by studying gaze strategies in skateboard jumps of different difficulty that had to be performed either with or without an obstacle. Method: Nine experienced skateboarders performed "Ollie" and "Kickflip" jumps either over an obstacle or over a…

Posture, head stability, and orientation recovery during vestibular regeneration in pigeons.

Science.gov (United States)

Dickman, J David; Lim, Insook

2004-09-01

Compensatory behavior such as oculomotor, gaze, and postural responses that occur during movement largely depend upon a functioning vestibular system. In the present study, the initial loss and subsequent recovery of postural and head stability in pigeons undergoing vestibular regeneration were examined. Adult pigeons were trained to manipulate a straight run chamber to peck an illuminated key for fluid reward. Six behavioral measures assessing performance, posture, and head stability were quantified. These included run latency, steps (walking), path negotiation (lane changes), gaze saccades, head bobs, and head shakes. Once normative values were obtained for four birds, complete lesion of all receptor cells and denervation of the epithelia in the vestibular endorgans were produced using a single intralabyrinthine application of streptomycin sulfate. Each bird was then tested at specific times during regeneration and the same behavioral measures examined. At 7 days post-streptomycin treatment (PST), all birds exhibited severe postural and head instability, with tremors, head shakes, staggering, and circling predominating. No normal trial runs, walking, gaze saccades, or head bobs were present. Many of these dysfunctions persisted through 3-4 weeks PST. Gradually, tremor and head shakes diminished and were replaced with an increasing number of normal head bobs during steps and gaze saccades. Beginning at 4 weeks PST, but largely inaccurate, was the observed initiation of directed steps, less staggering, and some successful path negotiation. As regeneration progressed, spatial orientation and navigation ability increased and, by 49 days PST, most trials were successful. By 70 days PST, all birds had recovered to pretreatment levels. Thus, it was observed that ataxia must subside, coincident with normalized head and postural stability prior to the recovery of spatial orientation and path navigation recovery. Parallels in recovery were drawn to hair cell regeneration

Off-the-Shelf Gaze Interaction

DEFF Research Database (Denmark)

San Agustin, Javier

People with severe motor-skill disabilities are often unable to use standard input devices such as a mouse or a keyboard to control a computer and they are, therefore, in strong need for alternative input devices. Gaze tracking offers them the possibility to use the movements of their eyes to int...

Facial Expressions Modulate the Ontogenetic Trajectory of Gaze-Following among Monkeys

Science.gov (United States)

Teufel, Christoph; Gutmann, Anke; Pirow, Ralph; Fischer, Julia

2010-01-01

Gaze-following, the tendency to direct one's attention to locations looked at by others, is a crucial aspect of social cognition in human and nonhuman primates. Whereas the development of gaze-following has been intensely studied in human infants, its early ontogeny in nonhuman primates has received little attention. Combining longitudinal and…

Photographic but not line-drawn faces show early perceptual neural sensitivity to eye gaze direction

Directory of Open Access Journals (Sweden)

Alejandra eRossi

2015-04-01

Full Text Available Our brains readily decode facial movements and changes in social attention, reflected in earlier and larger N170 event-related potentials (ERPs to viewing gaze aversions vs. direct gaze in real faces (Puce et al. 2000. In contrast, gaze aversions in line-drawn faces do not produce these N170 differences (Rossi et al., 2014, suggesting that physical stimulus properties or experimental context may drive these effects. Here we investigated the role of stimulus-induced context on neurophysiological responses to dynamic gaze. Sixteen healthy adults viewed line-drawn and real faces, with dynamic eye aversion and direct gaze transitions, and control stimuli (scrambled arrays and checkerboards while continuous electroencephalographic (EEG activity was recorded. EEG data from 2 temporo-occipital clusters of 9 electrodes in each hemisphere where N170 activity is known to be maximal were selected for analysis. N170 peak amplitude and latency, and temporal dynamics from event-related spectral perturbations (ERSPs were measured in 16 healthy subjects. Real faces generated larger N170s for averted vs. direct gaze motion, however, N170s to real and direct gaze were as large as those to respective controls. N170 amplitude did not differ across line-drawn gaze changes. Overall, bilateral mean gamma power changes for faces relative to control stimuli occurred between 150-350 ms, potentially reflecting signal detection of facial motion.Our data indicate that experimental context does not drive N170 differences to viewed gaze changes. Low-level stimulus properties, such as the high sclera/iris contrast change in real eyes likely drive the N170 changes to viewed aversive movements.

Assessing the Usability of Gaze-Adapted Interface against Conventional Eye-based Input Emulation

OpenAIRE

Kumar, Chandan; Menges, Raphael; Staab, Steffen

2017-01-01

In recent years, eye tracking systems have greatly improved, beginning to play a promising role as an input medium. Eye trackers can be used for application control either by simply emulating the mouse and keyboard devices in the traditional graphical user interface, or by customized interfaces for eye gaze events. In this work, we evaluate these two approaches to assess their impact in usability. We present a gaze-adapted Twitter application interface with direct interaction of eye gaze inpu...

Gender and facial dominance in gaze cuing: emotional context matters in the eyes that we follow.

Directory of Open Access Journals (Sweden)

Garian Ohlsen

Full Text Available Gaze following is a socio-cognitive process that provides adaptive information about potential threats and opportunities in the individual's environment. The aim of the present study was to investigate the potential interaction between emotional context and facial dominance in gaze following. We used the gaze cue task to induce attention to or away from the location of a target stimulus. In the experiment, the gaze cue either belonged to a (dominant looking male face or a (non-dominant looking female face. Critically, prior to the task, individuals were primed with pictures of threat or no threat to induce either a dangerous or safe environment. Findings revealed that the primed emotional context critically influenced the gaze cuing effect. While a gaze cue of the dominant male face influenced performance in both the threat and no-threat conditions, the gaze cue of the non-dominant female face only influenced performance in the no-threat condition. This research suggests an implicit, context-dependent follower bias, which carries implications for research on visual attention, social cognition, and leadership.

Right hemispheric dominance and interhemispheric cooperation in gaze-triggered reflexive shift of attention.

Science.gov (United States)

Okada, Takashi; Sato, Wataru; Kubota, Yasutaka; Toichi, Motomi; Murai, Toshiya

2012-03-01

The neural substrate for the processing of gaze remains unknown. The aim of the present study was to clarify which hemisphere dominantly processes and whether bilateral hemispheres cooperate with each other in gaze-triggered reflexive shift of attention. Twenty-eight normal subjects were tested. The non-predictive gaze cues were presented either in unilateral or bilateral visual fields. The subjects localized the target as soon as possible. Reaction times (RT) were shorter when gaze-cues were congruent toward than away from targets, whichever visual field they were presented in. RT were shorter in left than right visual field presentations. RT in mono-directional bilateral presentations were shorter than both of those in left and right presentations. When bi-directional bilateral cues were presented, RT were faster when valid cues were presented in the left than right visual fields. The right hemisphere appears to be dominant, and there is interhemispheric cooperation in gaze-triggered reflexive shift of attention. © 2012 The Authors. Psychiatry and Clinical Neurosciences © 2012 Japanese Society of Psychiatry and Neurology.

The effects of social pressure and emotional expression on the cone of gaze in patients with social anxiety disorder.

Science.gov (United States)

Harbort, Johannes; Spiegel, Julia; Witthöft, Michael; Hecht, Heiko

2017-06-01

Patients with social anxiety disorder suffer from pronounced fears in social situations. As gaze perception is crucial in these situations, we examined which factors influence the range of gaze directions where mutual gaze is experienced (the cone of gaze). The social stimulus was modified by changing the number of people (heads) present and the emotional expression of their faces. Participants completed a psychophysical task, in which they had to adjust the eyes of a virtual head to gaze at the edge of the range where mutual eye-contact was experienced. The number of heads affected the width of the gaze cone: the more heads, the wider the gaze cone. The emotional expression of the virtual head had no consistent effect on the width of the gaze cone, it did however affect the emotional state of the participants. Angry expressions produced the highest arousal values. Highest valence emerged from happy faces, lowest valence from angry faces. These results suggest that the widening of the gaze cone in social anxiety disorder is not primarily mediated by their altered emotional reactivity. Implications for gaze assessment and gaze training in therapeutic contexts are discussed. Due to interindividual variability, enlarged gaze cones are not necessarily indicative of social anxiety disorder, they merely constitute a correlate at the group level. Copyright © 2016 Elsevier Ltd. All rights reserved.

Eye-gaze patterns as students study worked-out examples in mechanics

Directory of Open Access Journals (Sweden)

Brian H. Ross

2010-10-01

Full Text Available This study explores what introductory physics students actually look at when studying worked-out examples. Our classroom experiences indicate that introductory physics students neither discuss nor refer to the conceptual information contained in the text of worked-out examples. This study is an effort to determine to what extent students incorporate the textual information into the way they study. Student eye-gaze patterns were recorded as they studied the examples to aid them in solving a target problem. Contrary to our expectations from classroom interactions, students spent 40±3% of their gaze time reading the textual information. Their gaze patterns were also characterized by numerous jumps between corresponding mathematical and textual information, implying that they were combining information from both sources. Despite this large fraction of time spent reading the text, student recall of the conceptual information contained therein remained very poor. We also found that having a particular problem in mind had no significant effects on the gaze-patterns or conceptual information retention.

MEG evidence for dynamic amygdala modulations by gaze and facial emotions.

Directory of Open Access Journals (Sweden)

Thibaud Dumas

Full Text Available Amygdala is a key brain region for face perception. While the role of amygdala in the perception of facial emotion and gaze has been extensively highlighted with fMRI, the unfolding in time of amydgala responses to emotional versus neutral faces with different gaze directions is scarcely known.Here we addressed this question in healthy subjects using MEG combined with an original source imaging method based on individual amygdala volume segmentation and the localization of sources in the amygdala volume. We found an early peak of amygdala activity that was enhanced for fearful relative to neutral faces between 130 and 170 ms. The effect of emotion was again significant in a later time range (310-350 ms. Moreover, the amygdala response was greater for direct relative averted gaze between 190 and 350 ms, and this effect was selective of fearful faces in the right amygdala.Altogether, our results show that the amygdala is involved in the processing and integration of emotion and gaze cues from faces in different time ranges, thus underlining its role in multiple stages of face perception.

Social eye gaze modulates processing of speech and co-speech gesture.

Science.gov (United States)

Holler, Judith; Schubotz, Louise; Kelly, Spencer; Hagoort, Peter; Schuetze, Manuela; Özyürek, Aslı

2014-12-01

In human face-to-face communication, language comprehension is a multi-modal, situated activity. However, little is known about how we combine information from different modalities during comprehension, and how perceived communicative intentions, often signaled through visual signals, influence this process. We explored this question by simulating a multi-party communication context in which a speaker alternated her gaze between two recipients. Participants viewed speech-only or speech+gesture object-related messages when being addressed (direct gaze) or unaddressed (gaze averted to other participant). They were then asked to choose which of two object images matched the speaker's preceding message. Unaddressed recipients responded significantly more slowly than addressees for speech-only utterances. However, perceiving the same speech accompanied by gestures sped unaddressed recipients up to a level identical to that of addressees. That is, when unaddressed recipients' speech processing suffers, gestures can enhance the comprehension of a speaker's message. We discuss our findings with respect to two hypotheses attempting to account for how social eye gaze may modulate multi-modal language comprehension. Copyright © 2014 Elsevier B.V. All rights reserved.

Revisiting the Relationship between the Processing of Gaze Direction and the Processing of Facial Expression

Science.gov (United States)

Ganel, Tzvi

2011-01-01

There is mixed evidence on the nature of the relationship between the perception of gaze direction and the perception of facial expressions. Major support for shared processing of gaze and expression comes from behavioral studies that showed that observers cannot process expression or gaze and ignore irrelevant variations in the other dimension.…

Quantifying the cognitive cost of laparo-endoscopic single-site surgeries: Gaze-based indices.

Science.gov (United States)

Di Stasi, Leandro L; Díaz-Piedra, Carolina; Ruiz-Rabelo, Juan Francisco; Rieiro, Héctor; Sanchez Carrion, Jose M; Catena, Andrés

2017-11-01

Despite the growing interest concerning the laparo-endoscopic single-site surgery (LESS) procedure, LESS presents multiple difficulties and challenges that are likely to increase the surgeon's cognitive cost, in terms of both cognitive load and performance. Nevertheless, there is currently no objective index capable of assessing the surgeon cognitive cost while performing LESS. We assessed if gaze-based indices might offer unique and unbiased measures to quantify LESS complexity and its cognitive cost. We expect that the assessment of surgeon's cognitive cost to improve patient safety by measuring fitness-for-duty and reducing surgeons overload. Using a wearable eye tracker device, we measured gaze entropy and velocity of surgical trainees and attending surgeons during two surgical procedures (LESS vs. multiport laparoscopy surgery [MPS]). None of the participants had previous experience with LESS. They performed two exercises with different complexity levels (Low: Pattern Cut vs. High: Peg Transfer). We also collected performance and subjective data. LESS caused higher cognitive demand than MPS, as indicated by increased gaze entropy in both surgical trainees and attending surgeons (exploration pattern became more random). Furthermore, gaze velocity was higher (exploration pattern became more rapid) for the LESS procedure independently of the surgeon's expertise. Perceived task complexity and laparoscopic accuracy confirmed gaze-based results. Gaze-based indices have great potential as objective and non-intrusive measures to assess surgeons' cognitive cost and fitness-for-duty. Furthermore, gaze-based indices might play a relevant role in defining future guidelines on surgeons' examinations to mark their achievements during the entire training (e.g. analyzing surgical learning curves). Copyright © 2017 Elsevier Ltd. All rights reserved.

Improvement of Expansive Soils Using Chemical Stabilizers

Science.gov (United States)

Ikizler, S. B.; Senol, A.; Khosrowshahi, S. K.; Hatipoğlu, M.

2014-12-01

The aim of this study is to investigate the effect of two chemical stabilizers on the swelling potential of expansive soil. A high plasticity sodium bentonite was used as the expansive soil. The additive materials including fly ash (FA) and lime (L) were evaluated as potential stabilizers to decrease the swelling pressure of bentonite. Depending on the type of additive materials, they were blended with bentonite in different percentages to assess the optimum state and approch the maximum swell pressure reduction. According to the results of swell pressure test, both fly ash and lime reduce the swelling potential of bentonite but the maximum improvement occurs using bentonite-lime mixture while the swelling pressure reduction approaches to 49%. The results reveal a significant reduction of swelling potential of expansive soil using chemical stabilizers. Keywords: Expansive soil; swell pressure; chemical stabilization; fly ash; lime

Coding gaze tracking data with chromatic gradients for VR Exposure Therapy

DEFF Research Database (Denmark)

Herbelin, Bruno; Grillon, Helena; De Heras Ciechomski, Pablo

2007-01-01

This article presents a simple and intuitive way to represent the eye-tracking data gathered during immersive virtual reality exposure therapy sessions. Eye-tracking technology is used to observe gaze movements during vir- tual reality sessions and the gaze-map chromatic gradient coding allows to...... is fully compatible with different VR exposure systems and provides clinically meaningful data....

Examining the durability of incidentally learned trust from gaze cues.

Science.gov (United States)

Strachan, James W A; Tipper, Steven P

2017-10-01

In everyday interactions we find our attention follows the eye gaze of faces around us. As this cueing is so powerful and difficult to inhibit, gaze can therefore be used to facilitate or disrupt visual processing of the environment, and when we experience this we infer information about the trustworthiness of the cueing face. However, to date no studies have investigated how long these impressions last. To explore this we used a gaze-cueing paradigm where faces consistently demonstrated either valid or invalid cueing behaviours. Previous experiments show that valid faces are subsequently rated as more trustworthy than invalid faces. We replicate this effect (Experiment 1) and then include a brief interference task in Experiment 2 between gaze cueing and trustworthiness rating, which weakens but does not completely eliminate the effect. In Experiment 3, we explore whether greater familiarity with the faces improves the durability of trust learning and find that the effect is more resilient with familiar faces. Finally, in Experiment 4, we push this further and show that evidence of trust learning can be seen up to an hour after cueing has ended. Taken together, our results suggest that incidentally learned trust can be durable, especially for faces that deceive.

Eye gaze tracking based on the shape of pupil image

Science.gov (United States)

Wang, Rui; Qiu, Jian; Luo, Kaiqing; Peng, Li; Han, Peng

2018-01-01

Eye tracker is an important instrument for research in psychology, widely used in attention, visual perception, reading and other fields of research. Because of its potential function in human-computer interaction, the eye gaze tracking has already been a topic of research in many fields over the last decades. Nowadays, with the development of technology, non-intrusive methods are more and more welcomed. In this paper, we will present a method based on the shape of pupil image to estimate the gaze point of human eyes without any other intrusive devices such as a hat, a pair of glasses and so on. After using the ellipse fitting algorithm to deal with the pupil image we get, we can determine the direction of the fixation by the shape of the pupil.The innovative aspect of this method is to utilize the new idea of the shape of the pupil so that we can avoid much complicated algorithm. The performance proposed is very helpful for the study of eye gaze tracking, which just needs one camera without infrared light to know the changes in the shape of the pupil to determine the direction of the eye gazing, no additional condition is required.

Reading pleasure : Light in August and the theory of the gendered gaze

NARCIS (Netherlands)

Visser, [No Value

1997-01-01

This article discusses various components of the theory of the gendered gaze, in order to construct a framework for an analysis of how William Faulkner understood and fictionally presented the mechanism of the gaze in Light in August. Linking theory and praxis, this article explores the relationship

COGAIN2009 - "Gaze interaction for those who want it most"

DEFF Research Database (Denmark)

, with substantial amounts of applications to support communication, learning and entertainment already in use. However, there are still some uncertainties about this new technology amongst communication specialists and funding institutions. The 5th COGAIN conference will focus on spreading the experiences of people...... using gaze interaction in their daily life to potential users and specialists who have yet to benefit from it. The theme of the conference is "Gaze interaction for those who want it most". We present a total of 18 papers that have been reviewed and accepted by leading researchers and communication...... specialists. Several papers address gaze-based access to computer applications and several papers focus on environmental control. Previous COGAIN conferences have been a most effective launch pad for original new research ideas. Some of them have since found their way into journals and other conferences...

Adaptive-Repetitive Visual-Servo Control of Low-Flying Aerial Robots via Uncalibrated High-Flying Cameras

Science.gov (United States)

Guo, Dejun; Bourne, Joseph R.; Wang, Hesheng; Yim, Woosoon; Leang, Kam K.

2017-08-01

This paper presents the design and implementation of an adaptive-repetitive visual-servo control system for a moving high-flying vehicle (HFV) with an uncalibrated camera to monitor, track, and precisely control the movements of a low-flying vehicle (LFV) or mobile ground robot. Applications of this control strategy include the use of high-flying unmanned aerial vehicles (UAVs) with computer vision for monitoring, controlling, and coordinating the movements of lower altitude agents in areas, for example, where GPS signals may be unreliable or nonexistent. When deployed, a remote operator of the HFV defines the desired trajectory for the LFV in the HFV's camera frame. Due to the circular motion of the HFV, the resulting motion trajectory of the LFV in the image frame can be periodic in time, thus an adaptive-repetitive control system is exploited for regulation and/or trajectory tracking. The adaptive control law is able to handle uncertainties in the camera's intrinsic and extrinsic parameters. The design and stability analysis of the closed-loop control system is presented, where Lyapunov stability is shown. Simulation and experimental results are presented to demonstrate the effectiveness of the method for controlling the movement of a low-flying quadcopter, demonstrating the capabilities of the visual-servo control system for localization (i.e.,, motion capturing) and trajectory tracking control. In fact, results show that the LFV can be commanded to hover in place as well as track a user-defined flower-shaped closed trajectory, while the HFV and camera system circulates above with constant angular velocity. On average, the proposed adaptive-repetitive visual-servo control system reduces the average RMS tracking error by over 77% in the image plane and over 71% in the world frame compared to using just the adaptive visual-servo control law.

Gazes and Bodies in the Pornographies of Desire

Directory of Open Access Journals (Sweden)

Mirko Lino

2013-06-01

Full Text Available Il saggio propone una lettura sociale della pornografia cinematografica usando la categoria dello sguardo e le sue declinazioni di genere. Partendo dal famoso saggio di Laura Mulvey, Visual Pleasure and Narrative Cinema (1975, si sposterà il centro dell’analisi dal cinema narrativo tradizionale al cinema pornografico, considerando quest’ultimo un modello che fa contrappunto al voyeurismo dello sguardo maschile (male gaze che la Mulvey riscontrava in alcuni film di Sternberg e di Hitckcock. Per dimostrare la natura contrappuntistica del cinema pornografico si metterà a confronto la medesima messa in scena di uno sguardo che desidera in due film molto differenti tra loro, Rear Window (1954 di Hitchcock e Behind the Green Door (1972 dei fratelli Mitchell. La natura contrappuntistica del porn movie si rintraccia anche nel dialogo che instaura con il cinema mainstream riguardo ai limiti del visibile in materia sessuale. Infine, la pornografia soddisfa la rappresentazione del desiderio delle altre identità di genere, mettendo in scena tipologie di sguardo adeguate – female gaze e queer gaze –, che diventano presto strumenti per una affermazione sociale della diversità sessuali.

Real-time gaze estimation via pupil center tracking

Directory of Open Access Journals (Sweden)

Cazzato Dario

2018-02-01

Full Text Available Automatic gaze estimation not based on commercial and expensive eye tracking hardware solutions can enable several applications in the fields of human computer interaction (HCI and human behavior analysis. It is therefore not surprising that several related techniques and methods have been investigated in recent years. However, very few camera-based systems proposed in the literature are both real-time and robust. In this work, we propose a real-time user-calibration-free gaze estimation system that does not need person-dependent calibration, can deal with illumination changes and head pose variations, and can work with a wide range of distances from the camera. Our solution is based on a 3-D appearance-based method that processes the images from a built-in laptop camera. Real-time performance is obtained by combining head pose information with geometrical eye features to train a machine learning algorithm. Our method has been validated on a data set of images of users in natural environments, and shows promising results. The possibility of a real-time implementation, combined with the good quality of gaze tracking, make this system suitable for various HCI applications.

Gaze-based assistive technology used in daily life by children with severe physical impairments - parents' experiences.

Science.gov (United States)

Borgestig, Maria; Rytterström, Patrik; Hemmingsson, Helena

2017-07-01

To describe and explore parents' experiences when their children with severe physical impairments receive gaze-based assistive technology (gaze-based assistive technology (AT)) for use in daily life. Semi-structured interviews were conducted twice, with one year in between, with parents of eight children with cerebral palsy that used gaze-based AT in their daily activities. To understand the parents' experiences, hermeneutical interpretations were used during data analysis. The findings demonstrate that for parents, children's gaze-based AT usage meant that children demonstrated agency, provided them with opportunities to show personality and competencies, and gave children possibilities to develop. Overall, children's gaze-based AT provides hope for a better future for their children with severe physical impairments; a future in which the children can develop and gain influence in life. Gaze-based AT provides children with new opportunities to perform activities and take initiatives to communicate, giving parents hope about the children's future.

Evaluation of a low-cost open-source gaze tracker

DEFF Research Database (Denmark)

San Agustin, Javier; Jensen, Henrik Tomra Skovsgaard Hegner; Møllenbach, Emilie

2010-01-01

This paper presents a low-cost gaze tracking system that is based on a webcam mounted close to the user's eye. The performance of the gaze tracker was evaluated in an eye-typing task using two different typing applications. Participants could type between 3.56 and 6.78 words per minute, depending...... on the typing system used. A pilot study to assess the usability of the system was also carried out in the home of a user with severe motor impairments. The user successfully typed on a wall-projected interface using his eye movements....

Mutual Disambiguation of Eye Gaze and Speech for Sight Translation and Reading

DEFF Research Database (Denmark)

Kulkarni, Rucha; Jain, Kritika; Bansal, Himanshu

2013-01-01

and composition of the two modalities was used for integration. F-measure for Eye-Gaze and Word Accuracy for ASR were used as metrics to evaluate our results. In reading task, we demonstrated a significant improvement in both Eye-Gaze f-measure and speech Word Accuracy. In sight translation task, significant...

MEG Evidence for Dynamic Amygdala Modulations by Gaze and Facial Emotions

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Dumas, Thibaud; Dubal, Stéphanie; Attal, Yohan; Chupin, Marie; Jouvent, Roland; Morel, Shasha; George, Nathalie

2013-01-01

Background Amygdala is a key brain region for face perception. While the role of amygdala in the perception of facial emotion and gaze has been extensively highlighted with fMRI, the unfolding in time of amydgala responses to emotional versus neutral faces with different gaze directions is scarcely known. Methodology/Principal Findings Here we addressed this question in healthy subjects using MEG combined with an original source imaging method based on individual amygdala volume segmentation and the localization of sources in the amygdala volume. We found an early peak of amygdala activity that was enhanced for fearful relative to neutral faces between 130 and 170 ms. The effect of emotion was again significant in a later time range (310–350 ms). Moreover, the amygdala response was greater for direct relative averted gaze between 190 and 350 ms, and this effect was selective of fearful faces in the right amygdala. Conclusion Altogether, our results show that the amygdala is involved in the processing and integration of emotion and gaze cues from faces in different time ranges, thus underlining its role in multiple stages of face perception. PMID:24040190

Investigation of gliding flight by flying fish

Science.gov (United States)

Park, Hyungmin; Jeon, Woo-Pyung; Choi, Haecheon

2006-11-01

The most successful flight capability of fish is observed in the flying fish. Furthermore, despite the difference between two medium (air and water), the flying fish is well evolved to have an excellent gliding performance as well as fast swimming capability. In this study, flying fish's morphological adaptation to gliding flight is experimentally investigated using dry-mounted darkedged-wing flying fish, Cypselurus Hiraii. Specifically, we examine the effects of the pectoral and pelvic fins on the aerodynamic performance considering (i) both pectoral and pelvic fins, (ii) pectoral fins only, and (iii) body only with both fins folded. Varying the attack angle, we measure the lift, drag and pitching moment at the free-stream velocity of 12m/s for each case. Case (i) has higher lift-to-drag ratio (i.e. longer gliding distance) and more enhanced longitudinal static stability than case (ii). However, the lift coefficient is smaller for case (i) than for case (ii), indicating that the pelvic fins are not so beneficial for wing loading. The gliding performance of flying fish is compared with those of other fliers and is found to be similar to those of insects such as the butterfly and fruitfly.

The sensation of the look: The gazes in Laurence Anyways

OpenAIRE

Schultz, Corey Kai Nelson

2018-01-01

This article analyses the gazes, looks, stares and glares in Laurence Anyways (Xavier Dolan, 2012), and examines their affective, interpretive, and symbolic qualities, and their potential to create viewer empathy through affect. The cinematic gaze can produce sensations of shame and fear, by offering a sequence of varied “encounters” to which viewers can react, before we have been given a character onto which we can deflect them, thus bypassing the representational, narrative and even the sym...

Exploiting Three-Dimensional Gaze Tracking for Action Recognition During Bimanual Manipulation to Enhance Human–Robot Collaboration

Directory of Open Access Journals (Sweden)

Alireza Haji Fathaliyan

2018-04-01

Full Text Available Human–robot collaboration could be advanced by facilitating the intuitive, gaze-based control of robots, and enabling robots to recognize human actions, infer human intent, and plan actions that support human goals. Traditionally, gaze tracking approaches to action recognition have relied upon computer vision-based analyses of two-dimensional egocentric camera videos. The objective of this study was to identify useful features that can be extracted from three-dimensional (3D gaze behavior and used as inputs to machine learning algorithms for human action recognition. We investigated human gaze behavior and gaze–object interactions in 3D during the performance of a bimanual, instrumental activity of daily living: the preparation of a powdered drink. A marker-based motion capture system and binocular eye tracker were used to reconstruct 3D gaze vectors and their intersection with 3D point clouds of objects being manipulated. Statistical analyses of gaze fixation duration and saccade size suggested that some actions (pouring and stirring may require more visual attention than other actions (reach, pick up, set down, and move. 3D gaze saliency maps, generated with high spatial resolution for six subtasks, appeared to encode action-relevant information. The “gaze object sequence” was used to capture information about the identity of objects in concert with the temporal sequence in which the objects were visually regarded. Dynamic time warping barycentric averaging was used to create a population-based set of characteristic gaze object sequences that accounted for intra- and inter-subject variability. The gaze object sequence was used to demonstrate the feasibility of a simple action recognition algorithm that utilized a dynamic time warping Euclidean distance metric. Averaged over the six subtasks, the action recognition algorithm yielded an accuracy of 96.4%, precision of 89.5%, and recall of 89.2%. This level of performance suggests that

Investigation of Aerodynamic Capabilities of Flying Fish in Gliding Flight

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Park, H.; Choi, H.

In the present study, we experimentally investigate the aerodynamic capabilities of flying fish. We consider four different flying fish models, which are darkedged-wing flying fishes stuffed in actual gliding posture. Some morphological parameters of flying fish such as lateral dihedral angle of pectoral fins, incidence angles of pectoral and pelvic fins are considered to examine their effect on the aerodynamic performance. We directly measure the aerodynamic properties (lift, drag, and pitching moment) for different morphological parameters of flying fish models. For the present flying fish models, the maximum lift coefficient and lift-to-drag ratio are similar to those of medium-sized birds such as the vulture, nighthawk and petrel. The pectoral fins are found to enhance the lift-to-drag ratio and the longitudinal static stability of gliding flight. On the other hand, the lift coefficient and lift-to-drag ratio decrease with increasing lateral dihedral angle of pectoral fins.

Attention and Gaze Control in Picture Naming, Word Reading, and Word Categorizing

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Roelofs, Ardi

2007-01-01

The trigger for shifting gaze between stimuli requiring vocal and manual responses was examined. Participants were presented with picture-word stimuli and left- or right-pointing arrows. They vocally named the picture (Experiment 1), read the word (Experiment 2), or categorized the word (Experiment 3) and shifted their gaze to the arrow to…

Gaze characteristics of elite and near-elite athletes in ice hockey defensive tactics.

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Martell, Stephen G; Vickers, Joan N

2004-04-01

Traditional visual search experiments, where the researcher pre-selects video-based scenes for the participant to respond to, shows that elite players make more efficient decisions than non-elites, but disagree on how they temporally regulate their gaze. Using the vision-in-action [J.N. Vickers, J. Exp. Psychol.: Human Percept. Perform. 22 (1996) 342] approach, we tested whether the significant gaze that differentiates elite and non-elite athletes occurred either: early in the task and was of more rapid duration [A.M. Williams et al., Res. Quart. Exer. Sport 65 (1994) 127; A.M. Williams and K. Davids, Res. Quart. Exer. Sport 69 (1998) 111], or late in the task and was of longer duration [W. Helsen, J.M. Pauwels, A cognitive approach to visual search in sport, in: D. Brogan, K. Carr (Eds.), Visual Search, vol. II, Taylor and Francis, London, 1992], or whether a more complex gaze control strategy was used that consisted of both early and rapid fixations followed by a late fixation of long duration prior to the final execution. We tested this using a live defensive zone task in ice hockey. Results indicated that athletes temporally regulated their gaze using two different gaze control strategies. First, fixation/tracking (F/T) gaze early in the trial were significantly shorter than the final F/T and confirmed that the elite group fixated the tactical locations more rapidly than the non-elite on successful plays. And secondly, the final F/T prior to critical movement initiation (i.e. F/T-1) was significantly longer for both groups, averaging 30% of the final part of the phase and occurred as the athletes isolated a single object or location to end the play. The results imply that expertise in defensive tactics is defined by a cascade of F/T, which began with the athletes fixating or tracking specific locations for short durations at the beginning of the play, and concluded with a final gaze of long duration to a relatively stable target at the end. The results are

Can gaze-contingent mirror-feedback from unfamiliar faces alter self-recognition?

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Estudillo, Alejandro J; Bindemann, Markus

2017-05-01

This study focuses on learning of the self, by examining how human observers update internal representations of their own face. For this purpose, we present a novel gaze-contingent paradigm, in which an onscreen face mimics observers' own eye-gaze behaviour (in the congruent condition), moves its eyes in different directions to that of the observers (incongruent condition), or remains static and unresponsive (neutral condition). Across three experiments, the mimicry of the onscreen face did not affect observers' perceptual self-representations. However, this paradigm influenced observers' reports of their own face. This effect was such that observers felt the onscreen face to be their own and that, if the onscreen gaze had moved on its own accord, observers expected their own eyes to move too. The theoretical implications of these findings are discussed.

Objective eye-gaze behaviour during face-to-face communication with proficient alaryngeal speakers: a preliminary study.

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Evitts, Paul; Gallop, Robert

2011-01-01

There is a large body of research demonstrating the impact of visual information on speaker intelligibility in both normal and disordered speaker populations. However, there is minimal information on which specific visual features listeners find salient during conversational discourse. To investigate listeners' eye-gaze behaviour during face-to-face conversation with normal, laryngeal and proficient alaryngeal speakers. Sixty participants individually participated in a 10-min conversation with one of four speakers (typical laryngeal, tracheoesophageal, oesophageal, electrolaryngeal; 15 participants randomly assigned to one mode of speech). All speakers were > 85% intelligible and were judged to be 'proficient' by two certified speech-language pathologists. Participants were fitted with a head-mounted eye-gaze tracking device (Mobile Eye, ASL) that calculated the region of interest and mean duration of eye-gaze. Self-reported gaze behaviour was also obtained following the conversation using a 10 cm visual analogue scale. While listening, participants viewed the lower facial region of the oesophageal speaker more than the normal or tracheoesophageal speaker. Results of non-hierarchical cluster analyses showed that while listening, the pattern of eye-gaze was predominantly directed at the lower face of the oesophageal and electrolaryngeal speaker and more evenly dispersed among the background, lower face, and eyes of the normal and tracheoesophageal speakers. Finally, results show a low correlation between self-reported eye-gaze behaviour and objective regions of interest data. Overall, results suggest similar eye-gaze behaviour when healthy controls converse with normal and tracheoesophageal speakers and that participants had significantly different eye-gaze patterns when conversing with an oesophageal speaker. Results are discussed in terms of existing eye-gaze data and its potential implications on auditory-visual speech perception. © 2011 Royal College of Speech

Age differences in conscious versus subconscious social perception: the influence of face age and valence on gaze following.

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Bailey, Phoebe E; Slessor, Gillian; Rendell, Peter G; Bennetts, Rachel J; Campbell, Anna; Ruffman, Ted

2014-09-01

Gaze following is the primary means of establishing joint attention with others and is subject to age-related decline. In addition, young but not older adults experience an own-age bias in gaze following. The current research assessed the effects of subconscious processing on these age-related differences. Participants responded to targets that were either congruent or incongruent with the direction of gaze displayed in supraliminal and subliminal images of young and older faces. These faces displayed either neutral (Study 1) or happy and fearful (Study 2) expressions. In Studies 1 and 2, both age groups demonstrated gaze-directed attention by responding faster to targets that were congruent as opposed to incongruent with gaze-cues. In Study 1, subliminal stimuli did not attenuate the age-related decline in gaze-cuing, but did result in an own-age bias among older participants. In Study 2, gaze-cuing was reduced for older relative to young adults in response to supraliminal stimuli, and this could not be attributed to reduced visual acuity or age group differences in the perceived emotional intensity of the gaze-cue faces. Moreover, there were no age differences in gaze-cuing when responding to subliminal faces that were emotionally arousing. In addition, older adults demonstrated an own-age bias for both conscious and subconscious gaze-cuing when faces expressed happiness but not fear. We discuss growing evidence for age-related preservation of subconscious relative to conscious social perception, as well as an interaction between face age and valence in social perception. PsycINFO Database Record (c) 2014 APA, all rights reserved.

Relationship between abstract thinking and eye gaze pattern in patients with schizophrenia

Science.gov (United States)

2014-01-01

Background Effective integration of visual information is necessary to utilize abstract thinking, but patients with schizophrenia have slow eye movement and usually explore limited visual information. This study examines the relationship between abstract thinking ability and the pattern of eye gaze in patients with schizophrenia using a novel theme identification task. Methods Twenty patients with schizophrenia and 22 healthy controls completed the theme identification task, in which subjects selected which word, out of a set of provided words, best described the theme of a picture. Eye gaze while performing the task was recorded by the eye tracker. Results Patients exhibited a significantly lower correct rate for theme identification and lesser fixation and saccade counts than controls. The correct rate was significantly correlated with the fixation count in patients, but not in controls. Conclusions Patients with schizophrenia showed impaired abstract thinking and decreased quality of gaze, which were positively associated with each other. Theme identification and eye gaze appear to be useful as tools for the objective measurement of abstract thinking in patients with schizophrenia. PMID:24739356

Gaze interaction with textual user interface

DEFF Research Database (Denmark)

Paulin Hansen, John; Lund, Haakon; Madsen, Janus Askø

2015-01-01

” option for text navigation. People readily understood how to execute RSVP command prompts and a majority of them preferred gaze input to a pen pointer. We present the concept of a smartwatch that can track eye movements and mediate command options whenever in proximity of intelligent devices...

Use of lime cement stabilized pavement construction

Energy Technology Data Exchange (ETDEWEB)

Kumar, M.A.; Raju, G.V.R.P. [JNTU College of Engineering, Kakinada (India). Dept. of Civil Engineering

2009-08-15

Expansive clay is a major source of heave induced structural distress. Swelling of expansive soils causes serious problems and produce damages to many structures. Many research organizations are doing extensive work on waste materials concerning the feasibility and environmental suitability. Fly ash, a waste by product from coal burning in thermal power stations, is abundant in India causing severe health, environmental and disposal problems. Attempts are made to investigate the stabilization process with model test tracks over expansive subgrade in flexible pavements. Cyclic plate load tests are carried out on the tracks with chemicals like lime and cement introduced in fly ash subbase laid on sand and expansive subgrades. Test results show that maximum load carrying capacity is obtained for stabilized fly ash subbase compared to untreated fly ash subbase.

Chasing behaviour and optomotor following in free-flying male blowflies: flight performance and interactions of the underlying control systems

Directory of Open Access Journals (Sweden)

Christine Trischler

2010-05-01

Full Text Available The chasing behaviour of male blowflies after small targets belongs to the most rapid and virtuosic visually guided behaviours found in nature. Since in a structured environment any turn towards a target inevitably leads to a displacement of the entire retinal image in the opposite direction, it might evoke optomotor following responses counteracting the turn. To analyse potential interactions between the control systems underlying chasing behaviour and optomotor following, respectively, we performed behavioural experiments on male blowflies and examined the characteristics of the two flight control systems in isolation and in combination. Three findings are particularly striking. (i The characteristic saccadic flight and gaze style – a distinctive feature of blowfly cruising flights – is largely abandoned when the entire visual surroundings move around the fly; in this case flies tend to follow the moving pattern in a relatively continuous and smooth way. (ii When male flies engage in following a small target, they also employ a smooth pursuit strategy. (iii Although blowflies are reluctant to fly at high background velocities, the performance and dynamical characteristics of the chasing system are not much affected when the background moves in either the same or in the opposite direction as the target. Hence, the optomotor following response is largely suppressed by the chasing system and does not much impair chasing performance.

Modeling eye gaze patterns in clinician-patient interaction with lag sequential analysis.

Science.gov (United States)

Montague, Enid; Xu, Jie; Chen, Ping-Yu; Asan, Onur; Barrett, Bruce P; Chewning, Betty

2011-10-01

The aim of this study was to examine whether lag sequential analysis could be used to describe eye gaze orientation between clinicians and patients in the medical encounter. This topic is particularly important as new technologies are implemented into multiuser health care settings in which trust is critical and nonverbal cues are integral to achieving trust. This analysis method could lead to design guidelines for technologies and more effective assessments of interventions. Nonverbal communication patterns are important aspects of clinician-patient interactions and may affect patient outcomes. The eye gaze behaviors of clinicians and patients in 110 videotaped medical encounters were analyzed using the lag sequential method to identify significant behavior sequences. Lag sequential analysis included both event-based lag and time-based lag. Results from event-based lag analysis showed that the patient's gaze followed that of the clinician, whereas the clinician's gaze did not follow the patient's. Time-based sequential analysis showed that responses from the patient usually occurred within 2 s after the initial behavior of the clinician. Our data suggest that the clinician's gaze significantly affects the medical encounter but that the converse is not true. Findings from this research have implications for the design of clinical work systems and modeling interactions. Similar research methods could be used to identify different behavior patterns in clinical settings (physical layout, technology, etc.) to facilitate and evaluate clinical work system designs.

Infants' Developing Understanding of Social Gaze

Science.gov (United States)

Beier, Jonathan S.; Spelke, Elizabeth S.

2012-01-01

Young infants are sensitive to self-directed social actions, but do they appreciate the intentional, target-directed nature of such behaviors? The authors addressed this question by investigating infants' understanding of social gaze in third-party interactions (N = 104). Ten-month-old infants discriminated between 2 people in mutual versus…

Eye gaze during comprehension of American Sign Language by native and beginning signers.

Science.gov (United States)

Emmorey, Karen; Thompson, Robin; Colvin, Rachael

2009-01-01

An eye-tracking experiment investigated where deaf native signers (N = 9) and hearing beginning signers (N = 10) look while comprehending a short narrative and a spatial description in American Sign Language produced live by a fluent signer. Both groups fixated primarily on the signer's face (more than 80% of the time) but differed with respect to fixation location. Beginning signers fixated on or near the signer's mouth, perhaps to better perceive English mouthing, whereas native signers tended to fixate on or near the eyes. Beginning signers shifted gaze away from the signer's face more frequently than native signers, but the pattern of gaze shifts was similar for both groups. When a shift in gaze occurred, the sign narrator was almost always looking at his or her hands and was most often producing a classifier construction. We conclude that joint visual attention and attention to mouthing (for beginning signers), rather than linguistic complexity or processing load, affect gaze fixation patterns during sign language comprehension.

Spatial updating depends on gaze direction even after loss of vision.

Science.gov (United States)

Reuschel, Johanna; Rösler, Frank; Henriques, Denise Y P; Fiehler, Katja

2012-02-15

Direction of gaze (eye angle + head angle) has been shown to be important for representing space for action, implying a crucial role of vision for spatial updating. However, blind people have no access to vision yet are able to perform goal-directed actions successfully. Here, we investigated the role of visual experience for localizing and updating targets as a function of intervening gaze shifts in humans. People who differed in visual experience (late blind, congenitally blind, or sighted) were briefly presented with a proprioceptive reach target while facing it. Before they reached to the target's remembered location, they turned their head toward an eccentric direction that also induced corresponding eye movements in sighted and late blind individuals. We found that reaching errors varied systematically as a function of shift in gaze direction only in participants with early visual experience (sighted and late blind). In the late blind, this effect was solely present in people with moveable eyes but not in people with at least one glass eye. Our results suggest that the effect of gaze shifts on spatial updating develops on the basis of visual experience early in life and remains even after loss of vision as long as feedback from the eyes and head is available.

Radiologically defining horizontal gaze using EOS imaging-a prospective study of healthy subjects and a retrospective audit.

Science.gov (United States)

Hey, Hwee Weng Dennis; Tan, Kimberly-Anne; Ho, Vivienne Chien-Lin; Azhar, Syifa Bte; Lim, Joel-Louis; Liu, Gabriel Ka-Po; Wong, Hee-Kit

2018-06-01

As sagittal alignment of the cervical spine is important for maintaining horizontal gaze, it is important to determine the former for surgical correction. However, horizontal gaze remains poorly-defined from a radiological point of view. The objective of this study was to establish radiological criteria to define horizontal gaze. This study was conducted at a tertiary health-care institution over a 1-month period. A prospective cohort of healthy patients was used to determine the best radiological criteria for defining horizontal gaze. A retrospective cohort of patients without rigid spinal deformities was used to audit the incidence of horizontal gaze. Two categories of radiological parameters for determining horizontal gaze were tested: (1) the vertical offset distances of key identifiable structures from the horizontal gaze axis and (2) imaginary lines convergent with the horizontal gaze axis. Sixty-seven healthy subjects underwent whole-body EOS radiographs taken in a directed standing posture. Horizontal gaze was radiologically defined using each parameter, as represented by their means, 95% confidence intervals (CIs), and associated 2 standard deviations (SDs). Subsequently, applying the radiological criteria, we conducted a retrospective audit of such radiographs (before the implementation of a strict radioimaging standardization). The mean age of our prospective cohort was 46.8 years, whereas that of our retrospective cohort was 37.2 years. Gender was evenly distributed across both cohorts. The four parameters with the lowest 95% CI and 2 SD were the distance offsets of the midpoint of the hard palate (A) and the base of the sella turcica (B), the horizontal convergents formed by the tangential line to the hard palate (C), and the line joining the center of the orbital orifice with the internal occipital protuberance (D). In the prospective cohort, good sensitivity (>98%) was attained when two or more parameters were used. Audit using Criterion B

Impact of cognitive and linguistic ability on gaze behavior in children with hearing impairment

Directory of Open Access Journals (Sweden)

Olof eSandgren

2013-11-01

Full Text Available In order to explore verbal-nonverbal integration, we investigated the influence of cognitive and linguistic ability on gaze behavior during spoken language conversation between children with mild-to-moderate hearing impairment (HI and normal-hearing (NH peers. Ten HI-NH and ten NH-NH dyads performed a referential communication task requiring description of faces. During task performance, eye movements and speech were tracked. Cox proportional hazards regression was used to model associations between performance on cognitive and linguistic tasks and the probability of gaze to the conversational partner’s face. Analyses compare the listeners in each dyad (HI: n = 10, mean age = 12;6 years, SD = 2;0, mean better ear pure-tone average 33.0 dB HL, SD = 7.8; NH: n = 10, mean age = 13;7 years, SD = 1;11. Group differences in gaze behavior – with HI gazing more to the conversational partner than NH – remained significant despite adjustment for ability on receptive grammar, expressive vocabulary, and complex working memory. Adjustment for phonological short term memory, as measured by nonword repetition, removed group differences, revealing an interaction between group membership and nonword repetition ability. Stratified analysis showed a twofold increase of the probability of gaze-to-partner for HI with low phonological short term memory capacity, and a decreased probability for HI with high capacity, as compared to NH peers. The results revealed differences in gaze behavior attributable to performance on a phonological short term memory task. Participants with hearing impairment and low phonological short term memory capacity showed a doubled probability of gaze to the conversational partner, indicative of a visual bias. The results stress the need to look beyond the hearing impairment in diagnostics and intervention. Acknowledgment of the finding requires clinical assessment of children with hearing impairment to be supported by tasks tapping

Tactile band : accessing gaze signals from the sighted in face-to-face communication

NARCIS (Netherlands)

Qiu, S.; Rauterberg, G.W.M.; Hu, J.

2016-01-01

Gaze signals, frequently used by the sighted in social interactions as visual cues, are hardly accessible for low-vision and blind people. A concept is proposed to help the blind people access and react to gaze signals in face-to-face communication. 20 blind and low-vision participants were

Does Gaze Direction Modulate Facial Expression Processing in Children with Autism Spectrum Disorder?

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Akechi, Hironori; Senju, Atsushi; Kikuchi, Yukiko; Tojo, Yoshikuni; Osanai, Hiroo; Hasegawa, Toshikazu

2009-01-01

Two experiments investigated whether children with autism spectrum disorder (ASD) integrate relevant communicative signals, such as gaze direction, when decoding a facial expression. In Experiment 1, typically developing children (9-14 years old; n = 14) were faster at detecting a facial expression accompanying a gaze direction with a congruent…

Real-time estimation of horizontal gaze angle by saccade integration using in-ear electrooculography.

Science.gov (United States)

Hládek, Ľuboš; Porr, Bernd; Brimijoin, W Owen

2018-01-01

The manuscript proposes and evaluates a real-time algorithm for estimating eye gaze angle based solely on single-channel electrooculography (EOG), which can be obtained directly from the ear canal using conductive ear moulds. In contrast to conventional high-pass filtering, we used an algorithm that calculates absolute eye gaze angle via statistical analysis of detected saccades. The estimated eye positions of the new algorithm were still noisy. However, the performance in terms of Pearson product-moment correlation coefficients was significantly better than the conventional approach in some instances. The results suggest that in-ear EOG signals captured with conductive ear moulds could serve as a basis for light-weight and portable horizontal eye gaze angle estimation suitable for a broad range of applications. For instance, for hearing aids to steer the directivity of microphones in the direction of the user's eye gaze.

Toward a reliable gaze-independent hybrid BCI combining visual and natural auditory stimuli.

Science.gov (United States)

Barbosa, Sara; Pires, Gabriel; Nunes, Urbano

2016-03-01

Brain computer interfaces (BCIs) are one of the last communication options for patients in the locked-in state (LIS). For complete LIS patients, interfaces must be gaze-independent due to their eye impairment. However, unimodal gaze-independent approaches typically present levels of performance substantially lower than gaze-dependent approaches. The combination of multimodal stimuli has been pointed as a viable way to increase users' performance. A hybrid visual and auditory (HVA) P300-based BCI combining simultaneously visual and auditory stimulation is proposed. Auditory stimuli are based on natural meaningful spoken words, increasing stimuli discrimination and decreasing user's mental effort in associating stimuli to the symbols. The visual part of the interface is covertly controlled ensuring gaze-independency. Four conditions were experimentally tested by 10 healthy participants: visual overt (VO), visual covert (VC), auditory (AU) and covert HVA. Average online accuracy for the hybrid approach was 85.3%, which is more than 32% over VC and AU approaches. Questionnaires' results indicate that the HVA approach was the less demanding gaze-independent interface. Interestingly, the P300 grand average for HVA approach coincides with an almost perfect sum of P300 evoked separately by VC and AU tasks. The proposed HVA-BCI is the first solution simultaneously embedding natural spoken words and visual words to provide a communication lexicon. Online accuracy and task demand of the approach compare favorably with state-of-the-art. The proposed approach shows that the simultaneous combination of visual covert control and auditory modalities can effectively improve the performance of gaze-independent BCIs. Copyright © 2015 Elsevier B.V. All rights reserved.

Diffusion and leachability index studies on stabilization of chromium contaminated soil using fly ash.

Science.gov (United States)

Kanchinadham, Sri Bala Kameswari; Narasimman, L M; Pedaballe, Vihita; Kalyanaraman, Chitra

2015-10-30

Experiments were performed to establish a feasible treatment process for the solidification and stabilization (S/S) of soil contaminated by leaching of Cr(VI) from Chromite ore processing residue (COPR). Reduction of the highly mobile Cr(VI) was performed using calcium polysulfide (CaS5) with a dosage of 3 times the molar stoichiometric ratio for the initial concentration of Cr(VI) present in the chromium contaminated soil (CCS). The CCS was solidified and stabilized (S/S) using fly ash (FA) in various proportions i.e., 1:1, 1:2, 1:3 (FA: CCS) with and without using reducing agent i.e., CaS5. Leachability tests such as Toxicity Characteristic Leaching Procedure (TCLP) and semi-dynamic long term leachability tests indicated that the CaS5 was effective in reduction of Cr(VI) followed by the S/S process. Leachability Index was derived from the results of the semi-dynamic long term leachability tests and was between 8 and 9, indicating that FA is an effective treatment for disposal into secured landfills for CCS. The characteristic compressive strength of the CaS5 treated CCS with FA mortar blocks were between 24.47 and 40.49 kg/cm(2). Considering the cost of CaS5 and FA, a total expenditure of Rs. 7826 i.e., US $ 130.4 would be required for remediation of one tonne of CCS. Copyright © 2015 Elsevier B.V. All rights reserved.

Gaze Embeddings for Zero-Shot Image Classification

NARCIS (Netherlands)

Karessli, N.; Akata, Z.; Schiele, B.; Bulling, A.

2017-01-01

Zero-shot image classification using auxiliary information, such as attributes describing discriminative object properties, requires time-consuming annotation by domain experts. We instead propose a method that relies on human gaze as auxiliary information, exploiting that even non-expert users have

Thermal stability of nano structured fly ash synthesized by high ...

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Casting, as a liquid phase process, is capable of producing products with ... materials, including stiffness, strength and wear resistance and reduce the density. .... been destroyed; and in this 10h milling stage the fly ash is in cold welding ..... 2004, Nanostructures and Nano materials- Synthesis, properties and Applications, ...

Biasing moral decisions by exploiting the dynamics of eye gaze.

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Pärnamets, Philip; Johansson, Petter; Hall, Lars; Balkenius, Christian; Spivey, Michael J; Richardson, Daniel C

2015-03-31

Eye gaze is a window onto cognitive processing in tasks such as spatial memory, linguistic processing, and decision making. We present evidence that information derived from eye gaze can be used to change the course of individuals' decisions, even when they are reasoning about high-level, moral issues. Previous studies have shown that when an experimenter actively controls what an individual sees the experimenter can affect simple decisions with alternatives of almost equal valence. Here we show that if an experimenter passively knows when individuals move their eyes the experimenter can change complex moral decisions. This causal effect is achieved by simply adjusting the timing of the decisions. We monitored participants' eye movements during a two-alternative forced-choice task with moral questions. One option was randomly predetermined as a target. At the moment participants had fixated the target option for a set amount of time we terminated their deliberation and prompted them to choose between the two alternatives. Although participants were unaware of this gaze-contingent manipulation, their choices were systematically biased toward the target option. We conclude that even abstract moral cognition is partly constituted by interactions with the immediate environment and is likely supported by gaze-dependent decision processes. By tracking the interplay between individuals, their sensorimotor systems, and the environment, we can influence the outcome of a decision without directly manipulating the content of the information available to them.

Subjects and Objects of the Embodied Gaze: Abbas Kiarostami and the Real of the Individual Perspective

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Gyenge Zsolt

2016-12-01

Full Text Available It is widely accepted that Abbas Kiarostami’s cinema revolves around the representation of the gaze. Many critics argue that he should be considered a late modernist who repeats the self-reflexive gestures of modernist European cinema decades after they were first introduced. The present paper will contradict this assertion by investigating the problematic of the Kiarostamian gaze and analyzing the perceptual side of the act of looking. I will argue that instead of focusing on the gaze of the spectator directed towards the filmic image, he exposes a gaze that is fully integrated into the reality to be captured on film. The second part of the paper will explain this by linking the concept of gaze to the Lacanian concept of the order of the Real. Finally, I will contextualize all this by discussing the Iranian director’s position between Eastern and Western traditions of representation.

Gaze Estimation for Off-Angle Iris Recognition Based on the Biometric Eye Model

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Karakaya, Mahmut [ORNL; Barstow, Del R [ORNL; Santos-Villalobos, Hector J [ORNL; Thompson, Joseph W [ORNL; Bolme, David S [ORNL; Boehnen, Chris Bensing [ORNL

2013-01-01

Iris recognition is among the highest accuracy biometrics. However, its accuracy relies on controlled high quality capture data and is negatively affected by several factors such as angle, occlusion, and dilation. Non-ideal iris recognition is a new research focus in biometrics. In this paper, we present a gaze estimation method designed for use in an off-angle iris recognition framework based on the ANONYMIZED biometric eye model. Gaze estimation is an important prerequisite step to correct an off-angle iris images. To achieve the accurate frontal reconstruction of an off-angle iris image, we first need to estimate the eye gaze direction from elliptical features of an iris image. Typically additional information such as well-controlled light sources, head mounted equipment, and multiple cameras are not available. Our approach utilizes only the iris and pupil boundary segmentation allowing it to be applicable to all iris capture hardware. We compare the boundaries with a look-up-table generated by using our biologically inspired biometric eye model and find the closest feature point in the look-up-table to estimate the gaze. Based on the results from real images, the proposed method shows effectiveness in gaze estimation accuracy for our biometric eye model with an average error of approximately 3.5 degrees over a 50 degree range.

Home-Based Computer Gaming in Vestibular Rehabilitation of Gaze and Balance Impairment.

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Szturm, Tony; Reimer, Karen M; Hochman, Jordan

2015-06-01

Disease or damage of the vestibular sense organs cause a range of distressing symptoms and functional problems that could include loss of balance, gaze instability, disorientation, and dizziness. A novel computer-based rehabilitation system with therapeutic gaming application has been developed. This method allows different gaze and head movement exercises to be coupled to a wide range of inexpensive, commercial computer games. It can be used in standing, and thus graded balance demands using a sponge pad can be incorporated into the program. A case series pre- and postintervention study was conducted of nine adults diagnosed with peripheral vestibular dysfunction who received a 12-week home rehabilitation program. The feasibility and usability of the home computer-based therapeutic program were established. Study findings revealed that using head rotation to interact with computer games, when coupled to demanding balance conditions, resulted in significant improvements in standing balance, dynamic visual acuity, gaze control, and walking performance. Perception of dizziness as measured by the Dizziness Handicap Inventory also decreased significantly. These preliminary findings provide support that a low-cost home game-based exercise program is well suited to train standing balance and gaze control (with active and passive head motion).

Exploring associations between gaze patterns and putative human mirror neuron system activity.

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Donaldson, Peter H; Gurvich, Caroline; Fielding, Joanne; Enticott, Peter G

2015-01-01

The human mirror neuron system (MNS) is hypothesized to be crucial to social cognition. Given that key MNS-input regions such as the superior temporal sulcus are involved in biological motion processing, and mirror neuron activity in monkeys has been shown to vary with visual attention, aberrant MNS function may be partly attributable to atypical visual input. To examine the relationship between gaze pattern and interpersonal motor resonance (IMR; an index of putative MNS activity), healthy right-handed participants aged 18-40 (n = 26) viewed videos of transitive grasping actions or static hands, whilst the left primary motor cortex received transcranial magnetic stimulation. Motor-evoked potentials recorded in contralateral hand muscles were used to determine IMR. Participants also underwent eyetracking analysis to assess gaze patterns whilst viewing the same videos. No relationship was observed between predictive gaze and IMR. However, IMR was positively associated with fixation counts in areas of biological motion in the videos, and negatively associated with object areas. These findings are discussed with reference to visual influences on the MNS, and the possibility that MNS atypicalities might be influenced by visual processes such as aberrant gaze pattern.

Exploring associations between gaze patterns and putative human mirror neuron system activity

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Peter Hugh Donaldson

2015-07-01

Full Text Available The human mirror neuron system (MNS is hypothesised to be crucial to social cognition. Given that key MNS-input regions such as the superior temporal sulcus are involved in biological motion processing, and mirror neuron activity in monkeys has been shown to vary with visual attention, aberrant MNS function may be partly attributable to atypical visual input. To examine the relationship between gaze pattern and interpersonal motor resonance (IMR; an index of putative MNS activity, healthy right-handed participants aged 18-40 (n = 26 viewed videos of transitive grasping actions or static hands, whilst the left primary motor cortex received transcranial magnetic stimulation (TMS. Motor-evoked potentials (MEPs recorded in contralateral hand muscles were used to determine IMR. Participants also underwent eyetracking analysis to assess gaze patterns whilst viewing the same videos. No relationship was observed between predictive gaze (PG and IMR. However, IMR was positively associated with fixation counts in areas of biological motion in the videos, and negatively associated with object areas. These findings are discussed with reference to visual influences on the MNS, and the possibility that MNS atypicalities might be influenced by visual processes such as aberrant gaze pattern.

High calcium fly ash geopolymer stabilized lateritic soil and granulated blast furnace slag blends as a pavement base material.

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Phummiphan, Itthikorn; Horpibulsuk, Suksun; Rachan, Runglawan; Arulrajah, Arul; Shen, Shui-Long; Chindaprasirt, Prinya

2018-01-05

Granulated Blast Furnace Slag (GBFS) was used as a replacement material in marginal lateritic soil (LS) while class C Fly Ash (FA) was used as a precursor for the geopolymerization process to develop a low-carbon pavement base material at ambient temperature. Unconfined Compression Strength (UCS) tests were performed to investigate the strength development of geopolymer stabilized LS/GBFS blends. Scanning Electron Microscopy and X-ray Diffraction analysis were undertaken to examine the role of the various influencing factors on UCS development. The influencing factors studied included GBFS content, Na 2 SiO 3 :NaOH ratio (NS:NH) and curing time. The 7-day soaked UCS of FA geopolymer stabilized LS/GBFS blends at various NS:NH ratios tested was found to satisfy the specifications of the Thailand national road authorities. The GBFS replacement was found to be insignificant for the improvement of the UCS of FA geopolymer stabilized LS/GBFS blends at low NS:NH ratio of 50:50. Microstructural analysis indicated the coexistence of Calcium Silicate Hydrate (CSH) and Sodium Alumino Silicate Hydrate products in FA geopolymer stabilized LS/GBFS blends. This research enables GBFS, which is traditionally considered as a waste material, to be used as a replacement and partially reactive material in FA geopolymer pavement applications. Copyright © 2017 Elsevier B.V. All rights reserved.

Real-time estimation of horizontal gaze angle by saccade integration using in-ear electrooculography.

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Ľuboš Hládek

Full Text Available The manuscript proposes and evaluates a real-time algorithm for estimating eye gaze angle based solely on single-channel electrooculography (EOG, which can be obtained directly from the ear canal using conductive ear moulds. In contrast to conventional high-pass filtering, we used an algorithm that calculates absolute eye gaze angle via statistical analysis of detected saccades. The estimated eye positions of the new algorithm were still noisy. However, the performance in terms of Pearson product-moment correlation coefficients was significantly better than the conventional approach in some instances. The results suggest that in-ear EOG signals captured with conductive ear moulds could serve as a basis for light-weight and portable horizontal eye gaze angle estimation suitable for a broad range of applications. For instance, for hearing aids to steer the directivity of microphones in the direction of the user's eye gaze.

The Gaze-Cueing Effect in the United States and Japan: Influence of Cultural Differences in Cognitive Strategies on Control of Attention

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Saki Takao

2018-01-01

Full Text Available The direction of gaze automatically and exogenously guides visual spatial attention, a phenomenon termed as the gaze-cueing effect. Although this effect arises when the duration of stimulus onset asynchrony (SOA between a non-predictive gaze cue and the target is relatively long, no empirical research has examined the factors underlying this extended cueing effect. Two experiments compared the gaze-cueing effect at longer SOAs (700 ms in Japanese and American participants. Cross-cultural studies on cognition suggest that Westerners tend to use a context-independent analytical strategy to process visual environments, whereas Asians use a context-dependent holistic approach. We hypothesized that Japanese participants would not demonstrate the gaze-cueing effect at longer SOAs because they are more sensitive to contextual information, such as the knowledge that the direction of a gaze is not predictive. Furthermore, we hypothesized that American participants would demonstrate the gaze-cueing effect at the long SOAs because they tend to follow gaze direction whether it is predictive or not. In Experiment 1, American participants demonstrated the gaze-cueing effect at the long SOA, indicating that their attention was driven by the central non-predictive gaze direction regardless of the SOAs. In Experiment 2, Japanese participants demonstrated no gaze-cueing effect at the long SOA, suggesting that the Japanese participants exercised voluntary control of their attention, which inhibited the gaze-cueing effect with the long SOA. Our findings suggest that the control of visual spatial attention elicited by social stimuli systematically differs between American and Japanese individuals.

The Gaze-Cueing Effect in the United States and Japan: Influence of Cultural Differences in Cognitive Strategies on Control of Attention.

Science.gov (United States)

Takao, Saki; Yamani, Yusuke; Ariga, Atsunori

2017-01-01

The direction of gaze automatically and exogenously guides visual spatial attention, a phenomenon termed as the gaze-cueing effect . Although this effect arises when the duration of stimulus onset asynchrony (SOA) between a non-predictive gaze cue and the target is relatively long, no empirical research has examined the factors underlying this extended cueing effect. Two experiments compared the gaze-cueing effect at longer SOAs (700 ms) in Japanese and American participants. Cross-cultural studies on cognition suggest that Westerners tend to use a context-independent analytical strategy to process visual environments, whereas Asians use a context-dependent holistic approach. We hypothesized that Japanese participants would not demonstrate the gaze-cueing effect at longer SOAs because they are more sensitive to contextual information, such as the knowledge that the direction of a gaze is not predictive. Furthermore, we hypothesized that American participants would demonstrate the gaze-cueing effect at the long SOAs because they tend to follow gaze direction whether it is predictive or not. In Experiment 1, American participants demonstrated the gaze-cueing effect at the long SOA, indicating that their attention was driven by the central non-predictive gaze direction regardless of the SOAs. In Experiment 2, Japanese participants demonstrated no gaze-cueing effect at the long SOA, suggesting that the Japanese participants exercised voluntary control of their attention, which inhibited the gaze-cueing effect with the long SOA. Our findings suggest that the control of visual spatial attention elicited by social stimuli systematically differs between American and Japanese individuals.

Gaze-based assistive technology used in daily life by children with severe physical impairments - parents' experiences

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Borgestig, Maria; Rytterstrom, Patrik; Hemmingsson, Helena

2017-01-01

Objective: To describe and explore parents' experiences when their children with severe physical impairments receive gaze-based assistive technology (gaze-based assistive technology (AT)) for use in daily life. Methods: Semi-structured interviews were conducted twice, with one year in between, with parents of eight children with cerebral palsy that used gaze-based AT in their daily activities. To understand the parents' experiences, hermeneutical interpretations were used during data analysis...

PyGaze: an open-source, cross-platform toolbox for minimal-effort programming of eyetracking experiments.

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Dalmaijer, Edwin S; Mathôt, Sebastiaan; Van der Stigchel, Stefan

2014-12-01

The PyGaze toolbox is an open-source software package for Python, a high-level programming language. It is designed for creating eyetracking experiments in Python syntax with the least possible effort, and it offers programming ease and script readability without constraining functionality and flexibility. PyGaze can be used for visual and auditory stimulus presentation; for response collection via keyboard, mouse, joystick, and other external hardware; and for the online detection of eye movements using a custom algorithm. A wide range of eyetrackers of different brands (EyeLink, SMI, and Tobii systems) are supported. The novelty of PyGaze lies in providing an easy-to-use layer on top of the many different software libraries that are required for implementing eyetracking experiments. Essentially, PyGaze is a software bridge for eyetracking research.

Eye and head movements shape gaze shifts in Indian peafowl.

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Yorzinski, Jessica L; Patricelli, Gail L; Platt, Michael L; Land, Michael F

2015-12-01

Animals selectively direct their visual attention toward relevant aspects of their environments. They can shift their attention using a combination of eye, head and body movements. While we have a growing understanding of eye and head movements in mammals, we know little about these processes in birds. We therefore measured the eye and head movements of freely behaving Indian peafowl (Pavo cristatus) using a telemetric eye-tracker. Both eye and head movements contributed to gaze changes in peafowl. When gaze shifts were smaller, eye movements played a larger role than when gaze shifts were larger. The duration and velocity of eye and head movements were positively related to the size of the eye and head movements, respectively. In addition, the coordination of eye and head movements in peafowl differed from that in mammals; peafowl exhibited a near-absence of the vestibulo-ocular reflex, which may partly result from the peafowl's ability to move their heads as quickly as their eyes. © 2015. Published by The Company of Biologists Ltd.

Flying Qualities (Qualites de Vol)

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1991-02-01

CIIANAIT DUMINIIG MA𔃼I1 FXCURSIOH /~o --- ~A 0- /10 CMFIGURE 4 AL-PHA-JETr ELEVATOR CONTROL CINEMATIC ; LP HEINi" KINEMATIC HORIZONTAL STABILIZER...ih-flight simulation is the ultimale assessment techntque providing high realism , flexibility, and credibility. rhe utilization (,f an in-fli:,ht si...1london, UK ()PERATIONAL H-ELICOPTER IIN - FLIGHT SIMULATOR (HIGH REALISM ) I(HIGH FLEAiBILITY Fligt t A tehrtqueTechnology implementation Flight t

Odorants and malodors associated with land application of biosolids stabilized with lime and coal fly ash.

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Laor, Yael; Naor, Moshe; Ravid, Uzi; Fine, Pinchas; Halachmi, Ilan; Chen, Yona; Baybikov, Rima

2011-01-01

Malodor emissions limit public acceptance of using municipal biosolids as natural organic resources in agricultural production. We aimed to identify major odorants and to evaluate odor concentrations associated with land application of anaerobically digested sewage sludges (Class B) and their alkaline (lime and coal fly ash)-stabilized products (Class A). These two types of biosolids were applied at 12.6 tonnes ha(-1) (dry weight) to microplots of very fine clayey Vertisol in the Jezreel Valley, northern Israel. The volatile organic compounds (VOCs) emitted from the biosolids before and during alkaline stabilization and after incorporation into the soil were analyzed by headspace solid-phase microextraction followed by gas chromatography-mass spectrometry. Odor concentrations at the plots were evaluated on site with a Nasal Ranger field olfactometer that sniffed over a defined land surface area through a static chamber. The odors emitted by anaerobically digested sewage sludges from three activated sludge water treatment plants had one characteristic chemical fingerprint. Alkaline stabilization emitted substantial odors associated with high concentrations of ammonia and release of nitrogen-containing VOCs and did not effectively reduce the potential odor annoyance. Odorous VOCs could be generated within the soil after biosolids incorporation, presumably because of anaerobic conditions within soil-biosolids aggregates. We propose that dimethyl disulfide and dimethyl trisulfide, which seem to be most related to the odor concentrations of biosolids-treated soil, be used as potential chemical markers for the odor annoyance associated with incorporation of anaerobically digested sewage sludges. by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Cheating experience: Guiding novices to adopt the gaze strategies of experts expedites the learning of technical laparoscopic skills.

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Vine, Samuel J; Masters, Rich S W; McGrath, John S; Bright, Elizabeth; Wilson, Mark R

2012-07-01

Previous research has demonstrated that trainees can be taught (via explicit verbal instruction) to adopt the gaze strategies of expert laparoscopic surgeons. The current study examined a software template designed to guide trainees to adopt expert gaze control strategies passively, without being provided with explicit instructions. We examined 27 novices (who had no laparoscopic training) performing 50 learning trials of a laparoscopic training task in either a discovery-learning (DL) group or a gaze-training (GT) group while wearing an eye tracker to assess gaze control. The GT group performed trials using a surgery-training template (STT); software that is designed to guide expert-like gaze strategies by highlighting the key locations on the monitor screen. The DL group had a normal, unrestricted view of the scene on the monitor screen. Both groups then took part in a nondelayed retention test (to assess learning) and a stress test (under social evaluative threat) with a normal view of the scene. The STT was successful in guiding the GT group to adopt an expert-like gaze strategy (displaying more target-locking fixations). Adopting expert gaze strategies led to an improvement in performance for the GT group, which outperformed the DL group in both retention and stress tests (faster completion time and fewer errors). The STT is a practical and cost-effective training interface that automatically promotes an optimal gaze strategy. Trainees who are trained to adopt the efficient target-locking gaze strategy of experts gain a performance advantage over trainees left to discover their own strategies for task completion. Copyright © 2012 Mosby, Inc. All rights reserved.

Does the 'P300' speller depend on eye gaze?

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Brunner, P.; Joshi, S.; Briskin, S.; Wolpaw, J. R.; Bischof, H.; Schalk, G.

2010-10-01

Many people affected by debilitating neuromuscular disorders such as amyotrophic lateral sclerosis, brainstem stroke or spinal cord injury are impaired in their ability to, or are even unable to, communicate. A brain-computer interface (BCI) uses brain signals, rather than muscles, to re-establish communication with the outside world. One particular BCI approach is the so-called 'P300 matrix speller' that was first described by Farwell and Donchin (1988 Electroencephalogr. Clin. Neurophysiol. 70 510-23). It has been widely assumed that this method does not depend on the ability to focus on the desired character, because it was thought that it relies primarily on the P300-evoked potential and minimally, if at all, on other EEG features such as the visual-evoked potential (VEP). This issue is highly relevant for the clinical application of this BCI method, because eye movements may be impaired or lost in the relevant user population. This study investigated the extent to which the performance in a 'P300' speller BCI depends on eye gaze. We evaluated the performance of 17 healthy subjects using a 'P300' matrix speller under two conditions. Under one condition ('letter'), the subjects focused their eye gaze on the intended letter, while under the second condition ('center'), the subjects focused their eye gaze on a fixation cross that was located in the center of the matrix. The results show that the performance of the 'P300' matrix speller in normal subjects depends in considerable measure on gaze direction. They thereby disprove a widespread assumption in BCI research, and suggest that this BCI might function more effectively for people who retain some eye-movement control. The applicability of these findings to people with severe neuromuscular disabilities (particularly in eye-movements) remains to be determined.

It Takes Time and Experience to Learn How to Interpret Gaze in Mentalistic Terms

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Leavens, David A.

2006-01-01

What capabilities are required for an organism to evince an "explicit" understanding of gaze as a mentalistic phenomenon? One possibility is that mentalistic interpretations of gaze, like concepts of unseen, supernatural beings, are culturally-specific concepts, acquired through cultural learning. These abstract concepts may either require a…

Gaze-related mimic word activates the frontal eye field and related network in the human brain: an fMRI study.

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Osaka, Naoyuki; Osaka, Mariko

2009-09-18

This is an fMRI study demonstrating new evidence that a mimic word highly suggestive of an eye gaze, heard by the ear, significantly activates the frontal eye field (FEF), inferior frontal gyrus (IFG), dorsolateral premotor area (PMdr) and superior parietal lobule (SPL) connected with the frontal-parietal network. However, hearing a non-sense words that did not imply gaze under the same task does not activate this area in humans. We concluded that the FEF would be a critical area for generating/processing an active gaze, evoked by an onomatopoeia word that implied gaze closely associated with social skill. We suggest that the implied active gaze may depend on prefrontal-parietal interactions that modify cognitive gaze led by spatial visual attention associated with the SPL.

How Do We Update Faces? Effects of Gaze Direction and Facial Expressions on Working Memory Updating

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Artuso, Caterina; Palladino, Paola; Ricciardelli, Paola

2012-01-01

The aim of the study was to investigate how the biological binding between different facial dimensions, and their social and communicative relevance, may impact updating processes in working memory (WM). We focused on WM updating because it plays a key role in ongoing processing. Gaze direction and facial expression are crucial and changeable components of face processing. Direct gaze enhances the processing of approach-oriented facial emotional expressions (e.g., joy), while averted gaze enh...

The Iron Cage and the Gaze: Interpreting Medical Control in the English Health System

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Mark Exworthy

2015-05-01

Full Text Available This paper seeks to determine the value of theoretical ideal-types of medical control. Whilst ideal types (such as the iron cage and gaze need revision in their application to medical settings, they remain useful in describing and explaining patterns of control and autonomy in the medical profession. The apparent transition from the cage to the gaze has often been over-stated since both types are found in many contemporary health reforms. Indeed, forms of neo-bureaucracy have emerged alongside surveillance of the gaze. These types are contextualised and elaborated in terms of two empirical examples: the management of medical performance and financial incentives for senior hospital doctors in England. Findings point towards the reformulation of medical control, an on-going re-stratification of the medical profession, and the internalisation of managerial discourses. The cumulative effect involves the medical profession’s ability to re-cast and enhance its position (vis-à-vis managerial interests.Keywords: medical profession, medical control, iron cage, gaze

Between Gazes: Feminist, Queer, and 'Other' Films

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Elias, Camelia

In this book Camelia Elias introduces key terms in feminist, queer, and postcolonial/diaspora film. Taking her point of departure in the question, "what do you want from me?" she detours through Lacanian theory of the gaze and reframes questions of subjectivity and representation in an entertaining...

The influence of social and symbolic cues on observers' gaze behaviour.

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Hermens, Frouke; Walker, Robin

2016-08-01

Research has shown that social and symbolic cues presented in isolation and at fixation have strong effects on observers, but it is unclear how cues compare when they are presented away from fixation and embedded in natural scenes. We here compare the effects of two types of social cue (gaze and pointing gestures) and one type of symbolic cue (arrow signs) on eye movements of observers under two viewing conditions (free viewing vs. a memory task). The results suggest that social cues are looked at more quickly, for longer and more frequently than the symbolic arrow cues. An analysis of saccades initiated from the cue suggests that the pointing cue leads to stronger cueing than the gaze and the arrow cue. While the task had only a weak influence on gaze orienting to the cues, stronger cue following was found for free viewing compared to the memory task. © 2015 The British Psychological Society.

Eye-gaze control of the computer interface: Discrimination of zoom intent

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Goldberg, J.H.

1993-01-01

An analysis methodology and associated experiment were developed to assess whether definable and repeatable signatures of eye-gaze characteristics are evident, preceding a decision to zoom-in, zoom-out, or not to zoom at a computer interface. This user intent discrimination procedure can have broad application in disability aids and telerobotic control. Eye-gaze was collected from 10 subjects in a controlled experiment, requiring zoom decisions. The eye-gaze data were clustered, then fed into a multiple discriminant analysis (MDA) for optimal definition of heuristics separating the zoom-in, zoom-out, and no-zoom conditions. Confusion matrix analyses showed that a number of variable combinations classified at a statistically significant level, but practical significance was more difficult to establish. Composite contour plots demonstrated the regions in parameter space consistently assigned by the MDA to unique zoom conditions. Peak classification occurred at about 1200--1600 msec. Improvements in the methodology to achieve practical real-time zoom control are considered

Method of Menu Selection by Gaze Movement Using AC EOG Signals

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Kanoh, Shin'ichiro; Futami, Ryoko; Yoshinobu, Tatsuo; Hoshimiya, Nozomu

A method to detect the direction and the distance of voluntary eye gaze movement from EOG (electrooculogram) signals was proposed and tested. In this method, AC-amplified vertical and horizontal transient EOG signals were classified into 8-class directions and 2-class distances of voluntary eye gaze movements. A horizontal and a vertical EOGs during eye gaze movement at each sampling time were treated as a two-dimensional vector, and the center of gravity of the sample vectors whose norms were more than 80% of the maximum norm was used as a feature vector to be classified. By the classification using the k-nearest neighbor algorithm, it was shown that the averaged correct detection rates on each subject were 98.9%, 98.7%, 94.4%, respectively. This method can avoid strict EOG-based eye tracking which requires DC amplification of very small signal. It would be useful to develop robust human interfacing systems based on menu selection for severely paralyzed patients.

Control and follow-up of fly ash roads - Communication and Acceptance; Kontroll och uppfoeljning av askvaegar - Kommunikation och acceptans

Energy Technology Data Exchange (ETDEWEB)

Macsik, Josef; Edeskaer, Tommy; Hellman, Fredrik

2011-10-15

The report is aimed at those who perform or plan to perform stabilization of the unbound layers or terrace gravel roads or industrial areas, with binder where a major binder component is fly ash from bio-peat or coal fuel. Stabilization of unbound layers of road structures is a promising technique from technical, economical and environmental point of view. The need of demonstration projects on road sections to show the relationship of laboratory measurements and field measurements are great in order to promote this stabilization technique. Results from follow-up of several stabilized distances and industrial surfaces are presented, where the fly ash is a binder component. The results complement the guidance, Munde et al. (2006) respect to durability, environmental characteristics on several years of perspective. Our hope is that report will serve as a support for the implementation of demonstration projects of stabilized terrace or unbound layers of fly ash as binder component.

Use of a Remote Eye-Tracker for the Analysis of Gaze during Treadmill Walking and Visual Stimuli Exposition

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V. Serchi

2016-01-01

Full Text Available The knowledge of the visual strategies adopted while walking in cognitively engaging environments is extremely valuable. Analyzing gaze when a treadmill and a virtual reality environment are used as motor rehabilitation tools is therefore critical. Being completely unobtrusive, remote eye-trackers are the most appropriate way to measure the point of gaze. Still, the point of gaze measurements are affected by experimental conditions such as head range of motion and visual stimuli. This study assesses the usability limits and measurement reliability of a remote eye-tracker during treadmill walking while visual stimuli are projected. During treadmill walking, the head remained within the remote eye-tracker workspace. Generally, the quality of the point of gaze measurements declined as the distance from the remote eye-tracker increased and data loss occurred for large gaze angles. The stimulus location (a dot-target did not influence the point of gaze accuracy, precision, and trackability during both standing and walking. Similar results were obtained when the dot-target was replaced by a static or moving 2D target and “region of interest” analysis was applied. These findings foster the feasibility of the use of a remote eye-tracker for the analysis of gaze during treadmill walking in virtual reality environments.

The Disturbance of Gaze in Progressive Supranuclear Palsy (PSP: Implications for Pathogenesis

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Athena L Chen

2010-12-01

Full Text Available Progressive supranuclear palsy (PSP is a disease of later life that is currently regarded as a form of neurodegenerative tauopathy. Disturbance of gaze is a cardinal clinical feature of PSP that often helps clinicians to establish the diagnosis. Since the neurobiology of gaze control is now well understood, it is possible to use eye movements as investigational tools to understand aspects of the pathogenesis of PSP. In this review, we summarize each disorder of gaze control that occurs in PSP, drawing on our studies of fifty patients, and on reports from other laboratories that have measured the disturbances of eye movements. When these gaze disorders are approached by considering each functional class of eye movements and its neurobiological basis, a distinct pattern of eye movement deficits emerges that provides insight into the pathogenesis of PSP. Although some aspects of all forms of eye movements are affected in PSP, the predominant defects concern vertical saccades (slow and hypometric, both up and down, impaired vergence, and inability to modulate the linear vestibulo-ocular reflex appropriately for viewing distance. These vertical and vergence eye movements habitually work in concert to enable visuomotor skills that are important during locomotion with the hands free. Taken with the prominent early feature of falls, these findings suggest that PSP tauopathy impairs a recently-evolved neural system concerned with bipedal locomotion in an erect posture and frequent gaze shifts between the distant environment and proximate hands. This approach provides a conceptual framework that can be used to address the nosological challenge posed by overlapping clinical and neuropathological features of neurodegenerative tauopathies.

Dynamic modeling of patient and physician eye gaze to understand the effects of electronic health records on doctor-patient communication and attention.

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Montague, Enid; Asan, Onur

2014-03-01

The aim of this study was to examine eye gaze patterns between patients and physicians while electronic health records were used to support patient care. Eye gaze provides an indication of physician attention to patient, patient/physician interaction, and physician behaviors such as searching for information and documenting information. A field study was conducted where 100 patient visits were observed and video recorded in a primary care clinic. Videos were then coded for gaze behaviors where patients' and physicians' gaze at each other and artifacts such as electronic health records were coded using a pre-established objective coding scheme. Gaze data were then analyzed using lag sequential methods. Results showed that there are several eye gaze patterns significantly dependent to each other. All doctor-initiated gaze patterns were followed by patient gaze patterns. Some patient-initiated gaze patterns were also followed by doctor gaze patterns significantly unlike the findings in previous studies. Health information technology appears to contribute to some of the new significant patterns that have emerged. Differences were also found in gaze patterns related to technology that differ from patterns identified in studies with paper charts. Several sequences related to patient-doctor-technology were also significant. Electronic health records affect the patient-physician eye contact dynamic differently than paper charts. This study identified several patterns of patient-physician interaction with electronic health record systems. Consistent with previous studies, physician initiated gaze is an important driver of the interactions between patient and physician and patient and technology. Published by Elsevier Ireland Ltd.

Design and construction of a remote piloted flying wing. B.S. Thesis

Science.gov (United States)

Costa, Alfred J.; Koopman, Fritz; Soboleski, Craig; Trieu, Thai-Ba; Duquette, Jaime; Krause, Scott; Susko, David; Trieu, Thuyba

1994-01-01

Currently, there is a need for a high-speed, high-lift civilian transport. Although unconventional, a flying wing could fly at speeds in excess of Mach 2 and still retain the capacity of a 747. The design of the flying wing is inherently unstable since it lacks a fuselage and a horizontal tail. The project goal was to design, construct, fly, and test a remote-piloted scale model flying wing. The project was completed as part of the NASA/USRA Advanced Aeronautics Design Program. These unique restrictions required us to implement several fundamental design changes from last year's Elang configuration including wing sweepback and wingtip endplates. Unique features such as a single ducted fan engine, composite structural materials, and an electrostatic stability system were incorporated. The result is the Banshee '94. Our efforts will aid future projects in design and construction techniques so that a viable flying wing can become an integral part of the aviation industry.

Gazing toward humans: a study on water rescue dogs using the impossible task paradigm.

Science.gov (United States)

D'Aniello, Biagio; Scandurra, Anna; Prato-Previde, Emanuela; Valsecchi, Paola

2015-01-01

Various studies have assessed the role of life experiences, including learning opportunities, living conditions and the quality of dog-human relationships, in the use of human cues and problem-solving ability. The current study investigates how and to what extent training affects the behaviour of dogs and the communication of dogs with humans by comparing dogs trained for a water rescue service and untrained pet dogs in the impossible task paradigm. Twenty-three certified water rescue dogs (the water rescue group) and 17 dogs with no training experience (the untrained group) were tested using a modified version of the impossible task described by Marshall-Pescini et al. in 2009. The results demonstrated that the water rescue dogs directed their first gaze significantly more often towards the owner and spent more time gazing toward two people compared to the untrained pet dogs. There was no difference between the dogs of the two groups as far as in the amount of time spent gazing at the owner or the stranger; neither in the interaction with the apparatus attempting to obtain food. The specific training regime, aimed at promoting cooperation during the performance of water rescue, could account for the longer gazing behaviour shown toward people by the water rescue dogs and the priority of gazing toward the owner. Copyright © 2014 Elsevier B.V. All rights reserved.

The application of electrocoagulation for the conversion of MSWI fly ash into nonhazardous materials.

Science.gov (United States)

Liao, Wing-Ping; Yang, Renbo; Kuo, Wei-Ting; Huang, Jui-Yuan

2014-05-01

This research investigated the electrocoagulation of municipal solid waste incineration (MSWI) fly ash at a liquid-to-solid ratio (L/S) of 20:1. The leachate that was obtained from this treatment was recovered for reutilization. Two different anodic electrodes were investigated, and two unit runs were conducted. In Unit I, the optimum anode was chosen, and in Unit II, the optimum anode and the recovered leachate were used to replace deionized water for repeating the same electrocoagulation experiments. The results indicate that the aluminum (Al) anode performed better than the iridium oxide (IrO2) anode. The electrocoagulation technique includes washing with water, changing the composition of the fly ash, and stabilizing the heavy metals in the ash. Washing with water can remove the soluble salts from fly ash, and the fly ash can be converted into Friedel's salt (3CaO·Al2O3·CaCl2·10H2O) under an uniform electric field and the sacrificial release of Al(+3) ions, which stabilizes the toxic heavy metals and brings the composition of the fly ash to within the regulatory limits of the toxicity characteristic leaching procedure (TCLP). Use of the Al anode to manage the MSWI fly ash and the leachate obtained from the electrocoagulation treatment is therefore feasible. Copyright © 2014 Elsevier Ltd. All rights reserved.

Latvian government in double jeopardy with EU, Latvijas Gaze

Index Scriptorium Estoniae

2005-01-01

Läti soovib saada Euroopa Komisjonilt ajapikendust gaasituru liberaliseerimiseks 2010. aastani ning lubab sel juhul sõlmida Latvijas Gaze'ga kokkuleppe, et viimane loobuks gaasitarnete ainuõigusest Lätis

Intranasal Oxytocin Treatment Increases Eye-Gaze Behavior toward the Owner in Ancient Japanese Dog Breeds

Directory of Open Access Journals (Sweden)

Miho Nagasawa

2017-09-01

Full Text Available Dogs acquired unique cognitive abilities during domestication, which is thought to have contributed to the formation of the human-dog bond. In European breeds, but not in wolves, a dog’s gazing behavior plays an important role in affiliative interactions with humans and stimulates oxytocin secretion in both humans and dogs, which suggests that this interspecies oxytocin and gaze-mediated bonding was also acquired during domestication. In this study, we investigated whether Japanese breeds, which are classified as ancient breeds and are relatively close to wolves genetically, establish a bond with their owners through gazing behavior. The subject dogs were treated with either oxytocin or saline before the starting of the behavioral testing. We also evaluated physiological changes in the owners during mutual gazing by analyzing their heart rate variability (HRV and subsequent urinary oxytocin levels in both dogs and their owners. We found that oxytocin treatment enhanced the gazing behavior of Japanese dogs and increased their owners’ urinary oxytocin levels, as was seen with European breeds; however, the measured durations of skin contact and proximity to their owners were relatively low. In the owners’ HRV readings, inter-beat (R-R intervals (RRI, the standard deviation of normal to normal inter-beat (R-R intervals (SDNN, and the root mean square of successive heartbeat interval differences (RMSSD were lower when the dogs were treated with oxytocin compared with saline. Furthermore, the owners of female dogs showed lower SDNN than the owners of male dogs. These results suggest that the owners of female Japanese dogs exhibit more tension during interactions, and apart from gazing behavior, the dogs may show sex differences in their interactions with humans as well. They also suggest that Japanese dogs use eye-gazing as an attachment behavior toward humans similar to European breeds; however, there is a disparity between the dog sexes when

[Left lateral gaze paresis due to subcortical hematoma in the right precentral gyrus].

Science.gov (United States)

Sato, K; Takamori, M

1998-03-01

We report a case of transient left lateral gaze paresis due to a hemorrhagic lesion restricted in the right precentral gyrus. A 74-year-old female experienced a sudden clumsiness of the left upper extremity. A neurological examination revealed a left central facial paresis, distal dominant muscle weakness in the left upper limb and left lateral gaze paresis. There were no other focal neurological signs. Laboratory data were all normal. Brain CTs and MRIs demonstrated a subcortical hematoma in the right precentral gyrus. The neurological symptoms and signs disappeared over seven days. A recent physiological study suggested that the human frontal eye field (FEF) is located in the posterior part of the middle frontal gyrus (Brodmann's area 8) and the precentral gyrus around the precentral sulcus. More recent studies stressed the role of the precentral sulcus and the precentral gyrus. Our case supports those physiological findings. The hematoma affected both the FEF and its underlying white matter in our case. We assume the lateral gaze paresis is attributable to the disruption of the fibers from the FEF. It is likely that fibers for motor control of the face, upper extremity, and lateral gaze lie adjacently in the subcortical area.

Subjects and Objects of the Embodied Gaze: Abbas Kiarostami and the Real of the Individual Perspective

OpenAIRE

Gyenge Zsolt

2016-01-01

It is widely accepted that Abbas Kiarostami’s cinema revolves around the representation of the gaze. Many critics argue that he should be considered a late modernist who repeats the self-reflexive gestures of modernist European cinema decades after they were first introduced. The present paper will contradict this assertion by investigating the problematic of the Kiarostamian gaze and analyzing the perceptual side of the act of looking. I will argue that instead of focusing on the gaze of the...

Briquetting fly ash from power plants for use as a charge in production of FeSiAl alloys

Energy Technology Data Exchange (ETDEWEB)

Sosnowski, R.; Jastrzebski, R.; Podbiol, S.; Mendecki, K.

1983-02-01

The paper discusses waste product utilization of fly ash from black coal combustion for production of alloys consisting of iron, silicon and aluminium under laboratory conditions. Proportion of fly ash and coal reducing agent was 60% and 40%, grain size distribution of fly ash and coal ranged from 0 to 0.4 mm. Coal pitch and waste products from the cellulose industry were used as binders (resin soap, waste sulfite liquor etc.). Briquetting pressure was 400 kG/cm/sup 2/. Fly ash briquets were stabilized 168 h long and dried from 0.5 h to 1.0 h at 373 to 523 C. Effects of briquet composition, binders, briquetting pressure, stabilizing and drying on physical and mechanical properties of fly ash briquets are analyzed. The results of analyses are shown in 4 diagrams. Shatter test was used for determining briquet properties. The test shows that fly ash briquets with coal pitch, resin soap and waste sulfite liquor used as binders are characterized by compression strength not lower than 245 x 10/sup 4/ Pa and produce less than 5% fines in the shatter test. The tested fly ash briquets are a suitable charge for metallurgy. Effects of fly ash utilization on environmental protection are discussed. (8 refs.)

How does image noise affect actual and predicted human gaze allocation in assessing image quality?

Science.gov (United States)

Röhrbein, Florian; Goddard, Peter; Schneider, Michael; James, Georgina; Guo, Kun

2015-07-01

A central research question in natural vision is how to allocate fixation to extract informative cues for scene perception. With high quality images, psychological and computational studies have made significant progress to understand and predict human gaze allocation in scene exploration. However, it is unclear whether these findings can be generalised to degraded naturalistic visual inputs. In this eye-tracking and computational study, we methodically distorted both man-made and natural scenes with Gaussian low-pass filter, circular averaging filter and Additive Gaussian white noise, and monitored participants' gaze behaviour in assessing perceived image qualities. Compared with original high quality images, distorted images attracted fewer numbers of fixations but longer fixation durations, shorter saccade distance and stronger central fixation bias. This impact of image noise manipulation on gaze distribution was mainly determined by noise intensity rather than noise type, and was more pronounced for natural scenes than for man-made scenes. We furthered compared four high performing visual attention models in predicting human gaze allocation in degraded scenes, and found that model performance lacked human-like sensitivity to noise type and intensity, and was considerably worse than human performance measured as inter-observer variance. Furthermore, the central fixation bias is a major predictor for human gaze allocation, which becomes more prominent with increased noise intensity. Our results indicate a crucial role of external noise intensity in determining scene-viewing gaze behaviour, which should be considered in the development of realistic human-vision-inspired attention models. Copyright © 2015 Elsevier Ltd. All rights reserved.

The Tourist Gaze and ‘Family Treasure Trails’ in Museums

DEFF Research Database (Denmark)

Larsen, Jonas; Svabo, Connie

2014-01-01

Museums are largely neglected in the tourist research literature. This is even more striking given that they are arguably designed for gazing. There is little doubt that “graying” of the Western population adds to the number and range of museums. And yet, even in adult museums, there will be chil......Museums are largely neglected in the tourist research literature. This is even more striking given that they are arguably designed for gazing. There is little doubt that “graying” of the Western population adds to the number and range of museums. And yet, even in adult museums......, there will be children who are “dragged along.” Museums are increasingly aware of such conflicts and dilemmas. Many museums offer printed booklets with “treasure trails.” They afford a trail through the museum that forms a treasure hunt for specific objects and correct answers to questions related to the objects....... This article draws attention to this overlooked, mundane technology and gives it its deserved share of the limelight. We are concerned with exploring ethnographically how trails are designed and especially used by young families in museums for gazing. The article gives insight into how children, broadly...

Eye Contact and Fear of Being Laughed at in a Gaze Discrimination Task

Directory of Open Access Journals (Sweden)

Jorge Torres-Marín

2017-11-01

Full Text Available Current approaches conceptualize gelotophobia as a personality trait characterized by a disproportionate fear of being laughed at by others. Consistently with this perspective, gelotophobes are also described as neurotic and introverted and as having a paranoid tendency to anticipate derision and mockery situations. Although research on gelotophobia has significantly progressed over the past two decades, no evidence exists concerning the potential effects of gelotophobia in reaction to eye contact. Previous research has pointed to difficulties in discriminating gaze direction as the basis of possible misinterpretations of others’ intentions or mental states. The aim of the present research was to examine whether gelotophobia predisposition modulates the effects of eye contact (i.e., gaze discrimination when processing faces portraying several emotional expressions. In two different experiments, participants performed an experimental gaze discrimination task in which they responded, as quickly and accurately as possible, to the eyes’ directions on faces displaying either a happy, angry, fear, neutral, or sad emotional expression. In particular, we expected trait-gelotophobia to modulate the eye contact effect, showing specific group differences in the happiness condition. The results of Study 1 (N = 40 indicated that gelotophobes made more errors than non-gelotophobes did in the gaze discrimination task. In contrast to our initial hypothesis, the happiness expression did not have any special role in the observed differences between individuals with high vs. low trait-gelotophobia. In Study 2 (N = 40, we replicated the pattern of data concerning gaze discrimination ability, even after controlling for individuals’ scores on social anxiety. Furthermore, in our second experiment, we found that gelotophobes did not exhibit any problem with identifying others’ emotions, or a general incorrect attribution of affective features, such as valence

Effect of COSMOS technologies in detoxifying municipal solid waste incineration fly ash, preliminary results

Science.gov (United States)

Piccinelli, Elsa; Lasagni, Marina; Collina, Elena; Bonaiti, Stefania; Bontempi, Elza

2017-05-01

This study investigates the effect of technologies for heavy metal stabilization on the concentration of PolyChlorinatedDibenzo-p-Dioxins (PCDD) and PolyChlorinatedDibenzoFurans (PCDF), abbreviated PCDD/F, in Municipal Solid Waste Incineration (MSWI) fly ash. We determined the variation of the Total Organic Carbon (TOC) and PCDD/F concentration between raw and stabilized material. The technologies, that already proved to be very promising for heavy metal entrapment, showed encouraging results also for PCDD/F detoxification. This result could be very impacting on the management of MSWI fly ash: at the best of our knowledge, there are no methods, in literature, that can provide good results in stabilization of heavy metals, and abatement of chlorinated organic pollutants contained in the same matrix.

Aerodynamic characteristics of flying fish in gliding flight.

Science.gov (United States)

Park, Hyungmin; Choi, Haecheon

2010-10-01

The flying fish (family Exocoetidae) is an exceptional marine flying vertebrate, utilizing the advantages of moving in two different media, i.e. swimming in water and flying in air. Despite some physical limitations by moving in both water and air, the flying fish has evolved to have good aerodynamic designs (such as the hypertrophied fins and cylindrical body with a ventrally flattened surface) for proficient gliding flight. Hence, the morphological and behavioral adaptations of flying fish to aerial locomotion have attracted great interest from various fields including biology and aerodynamics. Several aspects of the flight of flying fish have been determined or conjectured from previous field observations and measurements of morphometric parameters. However, the detailed measurement of wing performance associated with its morphometry for identifying the characteristics of flight in flying fish has not been performed yet. Therefore, in the present study, we directly measure the aerodynamic forces and moment on darkedged-wing flying fish (Cypselurus hiraii) models and correlated them with morphological characteristics of wing (fin). The model configurations considered are: (1) both the pectoral and pelvic fins spread out, (2) only the pectoral fins spread with the pelvic fins folded, and (3) both fins folded. The role of the pelvic fins was found to increase the lift force and lift-to-drag ratio, which is confirmed by the jet-like flow structure existing between the pectoral and pelvic fins. With both the pectoral and pelvic fins spread, the longitudinal static stability is also more enhanced than that with the pelvic fins folded. For cases 1 and 2, the lift-to-drag ratio was maximum at attack angles of around 0 deg, where the attack angle is the angle between the longitudinal body axis and the flying direction. The lift coefficient is largest at attack angles around 30∼35 deg, at which the flying fish is observed to emerge from the sea surface. From glide polar

Gaze-based hints during child-robot gameplay

NARCIS (Netherlands)

Mwangi, E.; Barakova, Emilia I.; Diaz, M.L.Z.; Mallofre, A.C.; Rauterberg, G.W.M.; Kheddar, A.; Yoshida, E.; Sam Ge, S.; Suzuki, K.; Cabibihan, J.J.; Eyssel, F.; He, H.

2017-01-01

This paper presents a study that examines whether gaze hints provided by a robot tutor influences the behavior of children in a card matching game. In this regard, we conducted a within-subjects experiment, in which children played a card game “Memory” in the presence of a robot tutor in two

Gaze Cueing by Pareidolia Faces

OpenAIRE

Kohske Takahashi; Katsumi Watanabe

2013-01-01

Visual images that are not faces are sometimes perceived as faces (the pareidolia phenomenon). While the pareidolia phenomenon provides people with a strong impression that a face is present, it is unclear how deeply pareidolia faces are processed as faces. In the present study, we examined whether a shift in spatial attention would be produced by gaze cueing of face-like objects. A robust cueing effect was observed when the face-like objects were perceived as faces. The magnitude of the cuei...

Holistic integration of gaze cues in visual face and body perception: Evidence from the composite design.

Science.gov (United States)

Vrancken, Leia; Germeys, Filip; Verfaillie, Karl

2017-01-01

A considerable amount of research on identity recognition and emotion identification with the composite design points to the holistic processing of these aspects in faces and bodies. In this paradigm, the interference from a nonattended face half on the perception of the attended half is taken as evidence for holistic processing (i.e., a composite effect). Far less research, however, has been dedicated to the concept of gaze. Nonetheless, gaze perception is a substantial component of face and body perception, and holds critical information for everyday communicative interactions. Furthermore, the ability of human observers to detect direct versus averted eye gaze is effortless, perhaps similar to identity perception and emotion recognition. However, the hypothesis of holistic perception of eye gaze has never been tested directly. Research on gaze perception with the composite design could facilitate further systematic comparison with other aspects of face and body perception that have been investigated using the composite design (i.e., identity and emotion). In the present research, a composite design was administered to assess holistic processing of gaze cues in faces (Experiment 1) and bodies (Experiment 2). Results confirmed that eye and head orientation (Experiment 1A) and head and body orientation (Experiment 2A) are integrated in a holistic manner. However, the composite effect was not completely disrupted by inversion (Experiments 1B and 2B), a finding that will be discussed together with implications for future research.

The Rethorics of Gaze in Luhrmann's "Postmodern Great Gatsby"

Directory of Open Access Journals (Sweden)

Paola Fallerini

2014-05-01

Adopting the perspective suggested by the rhetoric of the gaze (Laura Mulvey it is highlighted the metalinguistic and metatextual reflection through which this movie contributes to the critical interpretation of Fitzgerald’s novel.

Attention and gaze shifting in dual-task and go/no-go performance with vocal responding

NARCIS (Netherlands)

Lamers, M.J.M.; Roelofs, A.P.A.

2011-01-01

Evidence from go/no-go performance on the Eriksen flanker task with manual responding suggests that individuals gaze at stimuli just as long as needed to identify them (e.g.. Sanders, 1998). In contrast, evidence from dual-task performance with vocal responding suggests that gaze shifts occur after

Cultural differences in gaze and emotion recognition: Americans contrast more than Chinese.

Science.gov (United States)

Stanley, Jennifer Tehan; Zhang, Xin; Fung, Helene H; Isaacowitz, Derek M

2013-02-01

We investigated the influence of contextual expressions on emotion recognition accuracy and gaze patterns among American and Chinese participants. We expected Chinese participants would be more influenced by, and attend more to, contextual information than Americans. Consistent with our hypothesis, Americans were more accurate than Chinese participants at recognizing emotions embedded in the context of other emotional expressions. Eye-tracking data suggest that, for some emotions, Americans attended more to the target faces, and they made more gaze transitions to the target face than Chinese. For all emotions except anger and disgust, Americans appeared to use more of a contrasting strategy where each face was individually contrasted with the target face, compared with Chinese who used less of a contrasting strategy. Both cultures were influenced by contextual information, although the benefit of contextual information depended upon the perceptual dissimilarity of the contextual emotions to the target emotion and the gaze pattern employed during the recognition task. PsycINFO Database Record (c) 2013 APA, all rights reserved.

Stay tuned: Inter-individual neural synchronization during mutual gaze and joint attention

Directory of Open Access Journals (Sweden)

Daisuke N Saito

2010-11-01

Full Text Available Eye contact provides a communicative link between humans, prompting joint attention. As spontaneous brain activity may have an important role in coordination of neuronal processing within the brain, their inter-subject synchronization may occur during eye contact. To test this, we conducted simultaneous functional MRI in pairs of adults. Eye contact was maintained at baseline while the subjects engaged in real-time gaze exchange in a joint attention task. Averted gaze activated the bilateral occipital pole extending to the right posterior superior temporal sulcus, the dorso-medial prefrontal cortex, and bilateral inferior frontal gyrus. Following a partner’s gaze towards an object activated the left intraparietal sulcus. After all task-related effects were modeled out, inter-individual correlation analysis of residual time-courses was performed. Paired subjects showed more prominent correlations than non-paired subjects in the right inferior frontal gyrus, suggesting that this region is involved in sharing intention during eye contact that provides the context for joint attention.

Looking at Eye Gaze Processing and Its Neural Correlates in Infancy--Implications for Social Development and Autism Spectrum Disorder

Science.gov (United States)

Hoehl, Stefanie; Reid, Vincent M.; Parise, Eugenio; Handl, Andrea; Palumbo, Letizia; Striano, Tricia

2009-01-01

The importance of eye gaze as a means of communication is indisputable. However, there is debate about whether there is a dedicated neural module, which functions as an eye gaze detector and when infants are able to use eye gaze cues in a referential way. The application of neuroscience methodologies to developmental psychology has provided new…

Head mounted device for point-of-gaze estimation in three dimensions

DEFF Research Database (Denmark)

Hansen, Dan Witzner; Lidegaard, Morten; Krüger, Norbert

2014-01-01

This paper presents a fully calibrated extended geometric approach for gaze estimation in three dimensions (3D). The methodology is based on a geometric approach utilising a fully calibrated binocular setup constructed as a head-mounted system. The approach is based on utilisation of two ordinary...... in the horizontal and vertical dimensions regarding fixations. However, even though the workspace is limited, the fact that the system is designed as a head-mounted device, the workspace volume is relatively positioned to the pose of the device. Hence gaze can be estimated in 3D with relatively free head...

Influence of Gaze Direction on Face Recognition: A Sensitive Effect

Directory of Open Access Journals (Sweden)

Noémy Daury

2011-08-01

Full Text Available This study was aimed at determining the conditions in which eye-contact may improve recognition memory for faces. Different stimuli and procedures were tested in four experiments. The effect of gaze direction on memory was found when a simple “yes-no” recognition task was used but not when the recognition task was more complex (e.g., including “Remember-Know” judgements, cf. Experiment 2, or confidence ratings, cf. Experiment 4. Moreover, even when a “yes-no” recognition paradigm was used, the effect occurred with one series of stimuli (cf. Experiment 1 but not with another one (cf. Experiment 3. The difficulty to produce the positive effect of gaze direction on memory is discussed.

The Gaze-Cueing Effect in the United States and Japan: Influence of Cultural Differences in Cognitive Strategies on Control of Attention

OpenAIRE

Saki Takao; Yusuke Yamani; Atsunori Ariga

2018-01-01

The direction of gaze automatically and exogenously guides visual spatial attention, a phenomenon termed as the gaze-cueing effect. Although this effect arises when the duration of stimulus onset asynchrony (SOA) between a non-predictive gaze cue and the target is relatively long, no empirical research has examined the factors underlying this extended cueing effect. Two experiments compared the gaze-cueing effect at longer SOAs (700 ms) in Japanese and American participants. Cross-cultural st...

Context-sensitivity in Conversation. Eye gaze and the German Repair Initiator ‘bitte?’ (´pardon?´)

DEFF Research Database (Denmark)

Egbert, Maria

1996-01-01

. In addition, repair is sensitive to certain characteristics of social situations. The selection of a particular repair initiator, German bitte? ‘pardon?’, indexes that there is no mutual gaze between interlocutors; i.e., there is no common course of action. The selection of bitte? not only initiates repair......; it also spurs establishment of mutual gaze, and thus displays that there is attention to a common focus. (Conversation analysis, context, cross-linguistic analysis, repair, gaze, telephone conversation, co-present interaction, grammar and interaction)...

Gender and facial dominance in gaze cuing: Emotional context matters in the eyes that we follow

NARCIS (Netherlands)

Ohlsen, G.; van Zoest, W.; van Vugt, M.

2013-01-01

Gaze following is a socio-cognitive process that provides adaptive information about potential threats and opportunities in the individual's environment. The aim of the present study was to investigate the potential interaction between emotional context and facial dominance in gaze following. We

Autonomous social gaze model for an interactive virtual character in real-life settings

OpenAIRE

Yumak, Zerrin; van den Brink, Bram; Egges, Arjan

2018-01-01

This paper presents a gaze behavior model for an interactive virtual character situated in the real world. We are interested in estimating which user has an intention to interact, in other words which user is engaged with the virtual character. The model takes into account behavioral cues such as proximity, velocity, posture and sound, estimates an engagement score and drives the gaze behavior of the virtual character. Initially, we assign equal weights to these fea...

Improved remote gaze estimation using corneal reflection-adaptive geometric transforms

Science.gov (United States)

Ma, Chunfei; Baek, Seung-Jin; Choi, Kang-A.; Ko, Sung-Jea

2014-05-01

Recently, the remote gaze estimation (RGE) technique has been widely applied to consumer devices as a more natural interface. In general, the conventional RGE method estimates a user's point of gaze using a geometric transform, which represents the relationship between several infrared (IR) light sources and their corresponding corneal reflections (CRs) in the eye image. Among various methods, the homography normalization (HN) method achieves state-of-the-art performance. However, the geometric transform of the HN method requiring four CRs is infeasible for the case when fewer than four CRs are available. To solve this problem, this paper proposes a new RGE method based on three alternative geometric transforms, which are adaptive to the number of CRs. Unlike the HN method, the proposed method not only can operate with two or three CRs, but can also provide superior accuracy. To further enhance the performance, an effective error correction method is also proposed. By combining the introduced transforms with the error-correction method, the proposed method not only provides high accuracy and robustness for gaze estimation, but also allows for a more flexible system setup with a different number of IR light sources. Experimental results demonstrate the effectiveness of the proposed method.

Text Entry by Gazing and Smiling

Directory of Open Access Journals (Sweden)

Outi Tuisku

2013-01-01

Full Text Available Face Interface is a wearable prototype that combines the use of voluntary gaze direction and facial activations, for pointing and selecting objects on a computer screen, respectively. The aim was to investigate the functionality of the prototype for entering text. First, three on-screen keyboard layout designs were developed and tested (n=10 to find a layout that would be more suitable for text entry with the prototype than traditional QWERTY layout. The task was to enter one word ten times with each of the layouts by pointing letters with gaze and select them by smiling. Subjective ratings showed that a layout with large keys on the edge and small keys near the center of the keyboard was rated as the most enjoyable, clearest, and most functional. Second, using this layout, the aim of the second experiment (n=12 was to compare entering text with Face Interface to entering text with mouse. The results showed that text entry rate for Face Interface was 20 characters per minute (cpm and 27 cpm for the mouse. For Face Interface, keystrokes per character (KSPC value was 1.1 and minimum string distance (MSD error rate was 0.12. These values compare especially well with other similar techniques.

Sociability and gazing toward humans in dogs and wolves: Simple behaviors with broad implications.

Science.gov (United States)

Bentosela, Mariana; Wynne, C D L; D'Orazio, M; Elgier, A; Udell, M A R

2016-01-01

Sociability, defined as the tendency to approach and interact with unfamiliar people, has been found to modulate some communicative responses in domestic dogs, including gaze behavior toward the human face. The objective of this study was to compare sociability and gaze behavior in pet domestic dogs and in human-socialized captive wolves in order to identify the relative influence of domestication and learning in the development of the dog-human bond. In Experiment 1, we assessed the approach behavior and social tendencies of dogs and wolves to a familiar and an unfamiliar person. In Experiment 2, we compared the animal's duration of gaze toward a person's face in the presence of food, which the animals could see but not access. Dogs showed higher levels of interspecific sociability than wolves in all conditions, including those where attention was unavailable. In addition, dogs gazed longer at the person's face than wolves in the presence of out-of-reach food. The potential contributions of domestication, associative learning, and experiences during ontogeny to prosocial behavior toward humans are discussed. © 2016 Society for the Experimental Analysis of Behavior.

Eye Gaze Correlates of Motor Impairment in VR Observation of Motor Actions.

Science.gov (United States)

Alves, J; Vourvopoulos, A; Bernardino, A; Bermúdez I Badia, S

2016-01-01

This article is part of the Focus Theme of Methods of Information in Medicine on "Methodologies, Models and Algorithms for Patients Rehabilitation". Identify eye gaze correlates of motor impairment in a virtual reality motor observation task in a study with healthy participants and stroke patients. Participants consisted of a group of healthy subjects (N = 20) and a group of stroke survivors (N = 10). Both groups were required to observe a simple reach-and-grab and place-and-release task in a virtual environment. Additionally, healthy subjects were required to observe the task in a normal condition and a constrained movement condition. Eye movements were recorded during the observation task for later analysis. For healthy participants, results showed differences in gaze metrics when comparing the normal and arm-constrained conditions. Differences in gaze metrics were also found when comparing dominant and non-dominant arm for saccades and smooth pursuit events. For stroke patients, results showed longer smooth pursuit segments in action observation when observing the paretic arm, thus providing evidence that the affected circuitry may be activated for eye gaze control during observation of the simulated motor action. This study suggests that neural motor circuits are involved, at multiple levels, in observation of motor actions displayed in a virtual reality environment. Thus, eye tracking combined with action observation tasks in a virtual reality display can be used to monitor motor deficits derived from stroke, and consequently can also be used for rehabilitation of stroke patients.

The effects of varying contextual demands on age-related positive gaze preferences.

Science.gov (United States)

Noh, Soo Rim; Isaacowitz, Derek M

2015-06-01

Despite many studies on the age-related positivity effect and its role in visual attention, discrepancies remain regarding whether full attention is required for age-related differences to emerge. The present study took a new approach to this question by varying the contextual demands of emotion processing. This was done by adding perceptual distractions, such as visual and auditory noise, that could disrupt attentional control. Younger and older participants viewed pairs of happy-neutral and fearful-neutral faces while their eye movements were recorded. Facial stimuli were shown either without noise, embedded in a background of visual noise (low, medium, or high), or with simultaneous auditory babble. Older adults showed positive gaze preferences, looking toward happy faces and away from fearful faces; however, their gaze preferences tended to be influenced by the level of visual noise. Specifically, the tendency to look away from fearful faces was not present in conditions with low and medium levels of visual noise but was present when there were high levels of visual noise. It is important to note, however, that in the high-visual-noise condition, external cues were present to facilitate the processing of emotional information. In addition, older adults' positive gaze preferences disappeared or were reduced when they first viewed emotional faces within a distracting context. The current results indicate that positive gaze preferences may be less likely to occur in distracting contexts that disrupt control of visual attention. (c) 2015 APA, all rights reserved.

Gaze Behavior in a Natural Environment with a Task-Relevant Distractor: How the Presence of a Goalkeeper Distracts the Penalty Taker

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Johannes Kurz

2018-01-01

Full Text Available Gaze behavior in natural scenes has been shown to be influenced not only by top–down factors such as task demands and action goals but also by bottom–up factors such as stimulus salience and scene context. Whereas gaze behavior in the context of static pictures emphasizes spatial accuracy, gazing in natural scenes seems to rely more on where to direct the gaze involving both anticipative components and an evaluation of ongoing actions. Not much is known about gaze behavior in far-aiming tasks in which multiple task-relevant targets and distractors compete for the allocation of visual attention via gaze. In the present study, we examined gaze behavior in the far-aiming task of taking a soccer penalty. This task contains a proximal target, the ball; a distal target, an empty location within the goal; and a salient distractor, the goalkeeper. Our aim was to investigate where participants direct their gaze in a natural environment with multiple potential fixation targets that differ in task relevance and salience. Results showed that the early phase of the run-up seems to be driven by both the salience of the stimulus setting and the need to perform a spatial calibration of the environment. The late run-up, in contrast, seems to be controlled by attentional demands of the task with penalty takers having habitualized a visual routine that is not disrupted by external influences (e.g., the goalkeeper. In addition, when trying to shoot a ball as accurately as possible, penalty takers directed their gaze toward the ball in order to achieve optimal foot-ball contact. These results indicate that whether gaze is driven by salience of the stimulus setting or by attentional demands depends on the phase of the actual task.

Limitations of gaze transfer: without visual context, eye movements do not to help to coordinate joint action, whereas mouse movements do.

Science.gov (United States)

Müller, Romy; Helmert, Jens R; Pannasch, Sebastian

2014-10-01

Remote cooperation can be improved by transferring the gaze of one participant to the other. However, based on a partner's gaze, an interpretation of his communicative intention can be difficult. Thus, gaze transfer has been inferior to mouse transfer in remote spatial referencing tasks where locations had to be pointed out explicitly. Given that eye movements serve as an indicator of visual attention, it remains to be investigated whether gaze and mouse transfer differentially affect the coordination of joint action when the situation demands an understanding of the partner's search strategies. In the present study, a gaze or mouse cursor was transferred from a searcher to an assistant in a hierarchical decision task. The assistant could use this cursor to guide his movement of a window which continuously opened up the display parts the searcher needed to find the right solution. In this context, we investigated how the ease of using gaze transfer depended on whether a link could be established between the partner's eye movements and the objects he was looking at. Therefore, in addition to the searcher's cursor, the assistant either saw the positions of these objects or only a grey background. When the objects were visible, performance and the number of spoken words were similar for gaze and mouse transfer. However, without them, gaze transfer resulted in longer solution times and more verbal effort as participants relied more strongly on speech to coordinate the window movement. Moreover, an analysis of the spatio-temporal coupling of the transmitted cursor and the window indicated that when no visual object information was available, assistants confidently followed the searcher's mouse but not his gaze cursor. Once again, the results highlight the importance of carefully considering task characteristics when applying gaze transfer in remote cooperation. Copyright © 2013 Elsevier B.V. All rights reserved.

Novel Eye Movement Disorders in Whipple’s Disease—Staircase Horizontal Saccades, Gaze-Evoked Nystagmus, and Esotropia

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Aasef G. Shaikh

2017-07-01

Full Text Available Whipple’s disease, a rare systemic infectious disorder, is complicated by the involvement of the central nervous system in about 5% of cases. Oscillations of the eyes and the jaw, called oculo-masticatory myorhythmia, are pathognomonic of the central nervous system involvement but are often absent. Typical manifestations of the central nervous system Whipple’s disease are cognitive impairment, parkinsonism mimicking progressive supranuclear palsy with vertical saccade slowing, and up-gaze range limitation. We describe a unique patient with the central nervous system Whipple’s disease who had typical features, including parkinsonism, cognitive impairment, and up-gaze limitation; but also had diplopia, esotropia with mild horizontal (abduction more than adduction limitation, and vertigo. The patient also had gaze-evoked nystagmus and staircase horizontal saccades. Latter were thought to be due to mal-programmed small saccades followed by a series of corrective saccades. The saccades were disconjugate due to the concurrent strabismus. Also, we noted disconjugacy in the slow phase of gaze-evoked nystagmus. The disconjugacy of the slow phase of gaze-evoked nystagmus was larger during monocular viewing condition. We propose that interaction of the strabismic drifts of the covered eyes and the nystagmus drift, putatively at the final common pathway might lead to such disconjugacy.

Testing the dual-route model of perceived gaze direction: Linear combination of eye and head cues.

Science.gov (United States)

Otsuka, Yumiko; Mareschal, Isabelle; Clifford, Colin W G

2016-06-01

We have recently proposed a dual-route model of the effect of head orientation on perceived gaze direction (Otsuka, Mareschal, Calder, & Clifford, 2014; Otsuka, Mareschal, & Clifford, 2015), which computes perceived gaze direction as a linear combination of eye orientation and head orientation. By parametrically manipulating eye orientation and head orientation, we tested the adequacy of a linear model to account for the effect of horizontal head orientation on perceived direction of gaze. Here, participants adjusted an on-screen pointer toward the perceived gaze direction in two image conditions: Normal condition and Wollaston condition. Images in the Normal condition included a change in the visible part of the eye along with the change in head orientation, while images in the Wollaston condition were manipulated to have identical eye regions across head orientations. Multiple regression analysis with explanatory variables of eye orientation and head orientation revealed that linear models account for most of the variance both in the Normal condition and in the Wollaston condition. Further, we found no evidence that the model with a nonlinear term explains significantly more variance. Thus, the current study supports the dual-route model that computes the perceived gaze direction as a linear combination of eye orientation and head orientation.

Spatiotemporal characteristics of gaze of children with autism spectrum disorders while looking at classroom scenes.

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Takahiro Higuchi

Full Text Available Children with autism spectrum disorders (ASD who have neurodevelopmental impairments in social communication often refuse to go to school because of difficulties in learning in class. The exact cause of maladaptation to school in such children is unknown. We hypothesized that these children have difficulty in paying attention to objects at which teachers are pointing. We performed gaze behavior analysis of children with ASD to understand their difficulties in the classroom. The subjects were 26 children with ASD (19 boys and 7 girls; mean age, 8.6 years and 27 age-matched children with typical development (TD (14 boys and 13 girls; mean age, 8.2 years. We measured eye movements of the children while they performed free viewing of two movies depicting actual classes: a Japanese class in which a teacher pointed at cartoon characters and an arithmetic class in which the teacher pointed at geometric figures. In the analysis, we defined the regions of interest (ROIs as the teacher's face and finger, the cartoon characters and geometric figures at which the teacher pointed, and the classroom wall that contained no objects. We then compared total gaze time for each ROI between the children with ASD and TD by two-way ANOVA. Children with ASD spent less gaze time on the cartoon characters pointed at by the teacher; they spent more gaze time on the wall in both classroom scenes. We could differentiate children with ASD from those with TD almost perfectly by the proportion of total gaze time that children with ASD spent looking at the wall. These results suggest that children with ASD do not follow the teacher's instructions in class and persist in gazing at inappropriate visual areas such as walls. Thus, they may have difficulties in understanding content in class, leading to maladaptation to school.

Spatiotemporal characteristics of gaze of children with autism spectrum disorders while looking at classroom scenes.

Science.gov (United States)

Higuchi, Takahiro; Ishizaki, Yuko; Noritake, Atsushi; Yanagimoto, Yoshitoki; Kobayashi, Hodaka; Nakamura, Kae; Kaneko, Kazunari

2017-01-01

Children with autism spectrum disorders (ASD) who have neurodevelopmental impairments in social communication often refuse to go to school because of difficulties in learning in class. The exact cause of maladaptation to school in such children is unknown. We hypothesized that these children have difficulty in paying attention to objects at which teachers are pointing. We performed gaze behavior analysis of children with ASD to understand their difficulties in the classroom. The subjects were 26 children with ASD (19 boys and 7 girls; mean age, 8.6 years) and 27 age-matched children with typical development (TD) (14 boys and 13 girls; mean age, 8.2 years). We measured eye movements of the children while they performed free viewing of two movies depicting actual classes: a Japanese class in which a teacher pointed at cartoon characters and an arithmetic class in which the teacher pointed at geometric figures. In the analysis, we defined the regions of interest (ROIs) as the teacher's face and finger, the cartoon characters and geometric figures at which the teacher pointed, and the classroom wall that contained no objects. We then compared total gaze time for each ROI between the children with ASD and TD by two-way ANOVA. Children with ASD spent less gaze time on the cartoon characters pointed at by the teacher; they spent more gaze time on the wall in both classroom scenes. We could differentiate children with ASD from those with TD almost perfectly by the proportion of total gaze time that children with ASD spent looking at the wall. These results suggest that children with ASD do not follow the teacher's instructions in class and persist in gazing at inappropriate visual areas such as walls. Thus, they may have difficulties in understanding content in class, leading to maladaptation to school.

Hydrothermal treatment of municipal solid waste incineration fly ash for dioxin decomposition

International Nuclear Information System (INIS)

Hu, Yuyan; Zhang, Pengfei; Chen, Dezhen; Zhou, Bin; Li, Jianyi; Li, Xian-wei

2012-01-01

Highlights: ► The first study to apply Fe-sulfate in hydrothermal treatment of municipal solid waste incineration fly ash for dioxin decomposition. ► The first study to comprehensively evaluate the effect of hydrothermal treatment on dioxin decomposition and heavy metal stabilization in municipal solid waste incineration fly ash. ► Gaussian software chemical computational simulation was performed to investigate the mechanism of dioxin decomposition based on quantum chemistry calculation, and to support the experimental data by the calculation results. - Abstract: Hydrothermal treatment of MSWI fly ash was performed in this paper with a purpose to reduce its dioxin content. First a hydrothermal reactor was set up with a mixture of ferric sulphate and ferrous sulphate serviced as the reactant, then the effects caused by reaction conditions such as reaction temperature, pre-treatment by water-washing and reactant dosage were checked; the results showed that as a promising technology, hydrothermal treatment exhibited considerable high efficiencies in decomposition of PCDDs/PCDFs and good stabilization of heavy metals as well. Experimental results also showed that for dioxin destruction, higher reaction temperature is the most important influencing factor followed by Fe addition, and pre-treatment of raw fly ash by water-washing increased the destruction efficiencies of dioxins only very slightly. Finally with help of Gaussian software chemical computational simulation was performed to investigate the mechanism of dioxin decomposition based on quantum chemistry calculation. The calculation results were supported by the experimental data. The leaching toxicities of hydrothermal products were higher than upper limits defined in the latest Chinese standard GB 16889-2008 for sanitary landfill disposal, thus an auxiliary process is suggested after the hydrothermal treatment for heavy metal stabilization.

I Reach Faster When I See You Look: Gaze Effects in Human–Human and Human–Robot Face-to-Face Cooperation

Science.gov (United States)

Boucher, Jean-David; Pattacini, Ugo; Lelong, Amelie; Bailly, Gerard; Elisei, Frederic; Fagel, Sascha; Dominey, Peter Ford; Ventre-Dominey, Jocelyne

2012-01-01

Human–human interaction in natural environments relies on a variety of perceptual cues. Humanoid robots are becoming increasingly refined in their sensorimotor capabilities, and thus should now be able to manipulate and exploit these social cues in cooperation with their human partners. Previous studies have demonstrated that people follow human and robot gaze, and that it can help them to cope with spatially ambiguous language. Our goal is to extend these findings into the domain of action, to determine how human and robot gaze can influence the speed and accuracy of human action. We report on results from a human–human cooperation experiment demonstrating that an agent’s vision of her/his partner’s gaze can significantly improve that agent’s performance in a cooperative task. We then implement a heuristic capability to generate such gaze cues by a humanoid robot that engages in the same cooperative interaction. The subsequent human–robot experiments demonstrate that a human agent can indeed exploit the predictive gaze of their robot partner in a cooperative task. This allows us to render the humanoid robot more human-like in its ability to communicate with humans. The long term objectives of the work are thus to identify social cooperation cues, and to validate their pertinence through implementation in a cooperative robot. The current research provides the robot with the capability to produce appropriate speech and gaze cues in the context of human–robot cooperation tasks. Gaze is manipulated in three conditions: Full gaze (coordinated eye and head), eyes hidden with sunglasses, and head fixed. We demonstrate the pertinence of these cues in terms of statistical measures of action times for humans in the context of a cooperative task, as gaze significantly facilitates cooperation as measured by human response times. PMID:22563315

I Reach Faster When I See You Look: Gaze Effects in Human-Human and Human-Robot Face-to-Face Cooperation.

Science.gov (United States)

Boucher, Jean-David; Pattacini, Ugo; Lelong, Amelie; Bailly, Gerrard; Elisei, Frederic; Fagel, Sascha; Dominey, Peter Ford; Ventre-Dominey, Jocelyne

2012-01-01

Human-human interaction in natural environments relies on a variety of perceptual cues. Humanoid robots are becoming increasingly refined in their sensorimotor capabilities, and thus should now be able to manipulate and exploit these social cues in cooperation with their human partners. Previous studies have demonstrated that people follow human and robot gaze, and that it can help them to cope with spatially ambiguous language. Our goal is to extend these findings into the domain of action, to determine how human and robot gaze can influence the speed and accuracy of human action. We report on results from a human-human cooperation experiment demonstrating that an agent's vision of her/his partner's gaze can significantly improve that agent's performance in a cooperative task. We then implement a heuristic capability to generate such gaze cues by a humanoid robot that engages in the same cooperative interaction. The subsequent human-robot experiments demonstrate that a human agent can indeed exploit the predictive gaze of their robot partner in a cooperative task. This allows us to render the humanoid robot more human-like in its ability to communicate with humans. The long term objectives of the work are thus to identify social cooperation cues, and to validate their pertinence through implementation in a cooperative robot. The current research provides the robot with the capability to produce appropriate speech and gaze cues in the context of human-robot cooperation tasks. Gaze is manipulated in three conditions: Full gaze (coordinated eye and head), eyes hidden with sunglasses, and head fixed. We demonstrate the pertinence of these cues in terms of statistical measures of action times for humans in the context of a cooperative task, as gaze significantly facilitates cooperation as measured by human response times.

Gaze-informed, task-situated representation of space in primate hippocampus during virtual navigation

Science.gov (United States)

Wirth, Sylvia; Baraduc, Pierre; Planté, Aurélie; Pinède, Serge; Duhamel, Jean-René

2017-01-01

To elucidate how gaze informs the construction of mental space during wayfinding in visual species like primates, we jointly examined navigation behavior, visual exploration, and hippocampal activity as macaque monkeys searched a virtual reality maze for a reward. Cells sensitive to place also responded to one or more variables like head direction, point of gaze, or task context. Many cells fired at the sight (and in anticipation) of a single landmark in a viewpoint- or task-dependent manner, simultaneously encoding the animal’s logical situation within a set of actions leading to the goal. Overall, hippocampal activity was best fit by a fine-grained state space comprising current position, view, and action contexts. Our findings indicate that counterparts of rodent place cells in primates embody multidimensional, task-situated knowledge pertaining to the target of gaze, therein supporting self-awareness in the construction of space. PMID:28241007

Strange-face Illusions During Interpersonal-Gazing and Personality Differences of Spirituality.

Science.gov (United States)

Caputo, Giovanni B

Strange-face illusions are produced when two individuals gaze at each other in the eyes in low illumination for more than a few minutes. Usually, the members of the dyad perceive numinous apparitions, like the other's face deformations and perception of a stranger or a monster in place of the other, and feel a short lasting dissociation. In the present experiment, the influence of the spirituality personality trait on strength and number of strange-face illusions was investigated. Thirty participants were preliminarily tested for superstition (Paranormal Belief Scale, PBS) and spirituality (Spiritual Transcendence Scale, STS); then, they were randomly assigned to 15 dyads. Dyads performed the intersubjective gazing task for 10 minutes and, finally, strange-face illusions (measured through the Strange-Face Questionnaire, SFQ) were evaluated. The first finding was that SFQ was independent of PBS; hence, strange-face illusions during intersubjective gazing are authentically perceptual, hallucination-like phenomena, and not due to superstition. The second finding was that SFQ depended on the spiritual-universality scale of STS (a belief in the unitive nature of life; e.g., "there is a higher plane of consciousness or spirituality that binds all people") and the two variables were negatively correlated. Thus, strange-face illusions, in particular monstrous apparitions, could potentially disrupt binding among human beings. Strange-face illusions can be considered as 'projections' of the subject's unconscious into the other's face. In conclusion, intersubjective gazing at low illumination can be a tool for conscious integration of unconscious 'shadows of the Self' in order to reach completeness of the Self. Copyright © 2017 Elsevier Inc. All rights reserved.

Gaze movements and spatial working memory in collision avoidance: a traffic intersection task

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Gregor eHardiess

2013-06-01

Full Text Available Street crossing under traffic is an everyday activity including collision detection as well as avoidance of objects in the path of motion. Such tasks demand extraction and representation of spatio-temporal information about relevant obstacles in an optimized format. Relevant task information is extracted visually by the use of gaze movements and represented in spatial working memory. In a virtual reality traffic intersection task, subjects are confronted with a two-lane intersection where cars are appearing with different frequencies, corresponding to high and low traffic densities. Under free observation and exploration of the scenery (using unrestricted eye and head movements the overall task for the subjects was to predict the potential-of-collision (POC of the cars or to adjust an adequate driving speed in order to cross the intersection without collision (i.e., to find the free space for crossing. In a series of experiments, gaze movement parameters, task performance, and the representation of car positions within working memory at distinct time points were assessed in normal subjects as well as in neurological patients suffering from homonymous hemianopia. In the following, we review the findings of these experiments together with other studies and provide a new perspective of the role of gaze behavior and spatial memory in collision detection and avoidance, focusing on the following questions: (i which sensory variables can be identified supporting adequate collision detection? (ii How do gaze movements and working memory contribute to collision avoidance when multiple moving objects are present and (iii how do they correlate with task performance? (iv How do patients with homonymous visual field defects use gaze movements and working memory to compensate for visual field loss? In conclusion, we extend the theory of collision detection and avoidance in the case of multiple moving objects and provide a new perspective on the combined

Effects of Facial Symmetry and Gaze Direction on Perception of Social Attributes: A Study in Experimental Art History

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Per Olav Folgerø

2016-09-01

Full Text Available This article explores the possibility of testing hypotheses about art production in the past by collecting data in the present. We call this enterprise experimental art history. Why did medieval artists prefer to paint Christ with his face directed towards the beholder, while profane faces were noticeably more often painted in different degrees of profile? Is a preference for frontal faces motivated by deeper evolutionary and biological considerations? Head and gaze direction is a significant factor for detecting the intentions of others, and accurate detection of gaze direction depends on strong contrast between a dark iris and a bright sclera, a combination that is only found in humans among the primates. One uniquely human capacity is language acquisition, where the detection of shared or joint attention, for example through detection of gaze direction, contributes significantly to the ease of acquisition. The perceived face and gaze direction is also related to fundamental emotional reactions such as fear, aggression, empathy and sympathy. The fast-track modulator model presents a related fast and unconscious subcortical route that involves many central brain areas. Activity in this pathway mediates the affective valence of the stimulus. In particular different sub-regions of the amygdala show specific activation as response to gaze direction, head orientation, and the valence of facial expression.We present three experiments on the effects of face orientation and gaze direction on the judgments of social attributes. We observed that frontal faces with direct gaze were more highly associated with positive adjectives. Does this help to associate positive values to the Holy Face in a Western context? The formal result indicates that the Holy Face is perceived more positively than profiles with both direct and averted gaze. Two control studies, using a Brazilian and a Dutch database of photographs, showed a similar but weaker effect with a

UTILIZATION OF TORAY FLY ASH AS FILLER SUBSTITUTION IN THE HOT ROLLED SHEET-WEARING COURSE (HRS-WC MIXTURE

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F. Candra

2012-02-01

Full Text Available In road construction materials, the utilization of fly ash as additive materials is limited and also small in quantity, while the disposal of fly ash is quite high. An abundance of fly ash can be found at PT Toray Company in Jakarta and Surabaya. Toray fly ash is disposed coal ash resulting from coal-fired electricity generating power plants. Toray fly ash in this research is used as substitute mineral filler in asphalt paving mixtures. Research on utilization of Toray fly ash as filler is conducted in the Hot Rolled Sheet – Wearing Course Mixture.  Filler content in the HRS –WC mixture is 9%. Variations of Toray fly ash in the mixture tested are 0%, 25%, 50%, 75%, 100% and the variations of asphalt content are 6%, 6.5%, 7%, 7.5%, 8%. Marshall test is  performed to determine the Optimum Asphalt Content  and Marshall Stability, Indirect Tensile Strength (ITS test and Tensile Strength Ratio (TSR to select the optimum Toray fly ash utilization in the mixture based on the moisture susceptibility of specimens. The research results show that in variations of 0%, 25%, 50%, 75% and 100% Toray fly ash in the HRS-WC Mixture, the Optimum Asphalt Contents are at 6.8%, 7.0%, 7.0%, 7.1% and 7.6%  and Marshall Stability values of the variations are 1649 kg, 1541 kg, 1568 kg, 1678 kg, 1718 kg respectively. TSR values in variations of Toray fly ash are 98.32%, 90.28%, 89.38%, 87.62%, 64.71% respectively, with Minimum TSR value required is 80%. Based on the overall parameters, the optimum Toray fly ash utilization in the HRS-WC Mixture recommended is 75% of Toray fly ash at 7.1% Optimum Asphalt Content.

Age differences in conscious versus subconscious social perception: The influence of face age and valence on gaze following.

OpenAIRE

Bailey, P.E.; Slessor, G.; Rendell, P.G.; Bennetts, Rachel; Campbell, A.; Ruffman, T.

2014-01-01

Gaze following is the primary means of establishing joint attention with others and is subject to age-related decline. In addition, young but not older adults experience an own-age bias in gaze following. The current research assessed the effects of subconscious processing on these age-related differences. Participants responded to targets that were either congruent or incongruent with the direction of gaze displayed in supraliminal and subliminal images of young and older faces. These faces ...

Learning to interact with a computer by gaze

DEFF Research Database (Denmark)

Aoki, Hirotaka; Hansen, John Paulin; Itoh, Kenji

2008-01-01

that inefficient eye movements was dramatically reduced after only 15 to 25 sentences of typing, equal to approximately 3-4 hours of practice. The performance data fits a general learning model based on the power law of practice. The learning model can be used to estimate further improvements in gaze typing...

The influence of banner advertisements on attention and memory: human faces with averted gaze can enhance advertising effectiveness.

Science.gov (United States)

Sajjacholapunt, Pitch; Ball, Linden J

2014-01-01

Research suggests that banner advertisements used in online marketing are often overlooked, especially when positioned horizontally on webpages. Such inattention invariably gives rise to an inability to remember advertising brands and messages, undermining the effectiveness of this marketing method. Recent interest has focused on whether human faces within banner advertisements can increase attention to the information they contain, since the gaze cues conveyed by faces can influence where observers look. We report an experiment that investigated the efficacy of faces located in banner advertisements to enhance the attentional processing and memorability of banner contents. We tracked participants' eye movements when they examined webpages containing either bottom-right vertical banners or bottom-center horizontal banners. We also manipulated facial information such that banners either contained no face, a face with mutual gaze or a face with averted gaze. We additionally assessed people's memories for brands and advertising messages. Results indicated that relative to other conditions, the condition involving faces with averted gaze increased attention to the banner overall, as well as to the advertising text and product. Memorability of the brand and advertising message was also enhanced. Conversely, in the condition involving faces with mutual gaze, the focus of attention was localized more on the face region rather than on the text or product, weakening any memory benefits for the brand and advertising message. This detrimental impact of mutual gaze on attention to advertised products was especially marked for vertical banners. These results demonstrate that the inclusion of human faces with averted gaze in banner advertisements provides a promising means for marketers to increase the attention paid to such adverts, thereby enhancing memory for advertising information.

The influence of banner advertisements on attention and memory: Human faces with averted gaze can enhance advertising effectiveness

Directory of Open Access Journals (Sweden)

Pitch eSajjacholapunt

2014-03-01

Full Text Available Research suggests that banner advertisements used in online marketing are often overlooked, especially when positioned horizontally on webpages. Such inattention invariably gives rise to an inability to remember advertising brands and messages, undermining the effectiveness of this marketing method. Recent interest has focused on whether human faces within banner advertisements can increase attention to the information they contain, since the gaze cues conveyed by faces can influence where observers look. We report an experiment that investigated the efficacy of faces located in banner advertisements to enhance the attentional processing and memorability of banner contents. We tracked participants’ eye movements when they examined webpages containing either bottom-right vertical banners or bottom-centre horizontal banners. We also manipulated facial information such that banners either contained no face, a face with mutual gaze or a face with averted gaze. We additionally assessed people’s memories for brands and advertising messages. Results indicated that relative to other conditions, the condition involving faces with averted gaze increased attention to the banner overall, as well as to the advertising text and product. Memorability of the brand and advertising message was also enhanced. Conversely, in the condition involving faces with mutual gaze, the focus of attention was localised more on the face region rather than on the text or product, weakening any memory benefits for the brand and advertising message. This detrimental impact of mutual gaze on attention to advertised products was especially marked for vertical banners. These results demonstrate that the inclusion of human faces with averted gaze in banner advertisements provides a promising means for marketers to increase the attention paid to such adverts, thereby enhancing memory for advertising information.

Proceedings from the 2nd International Symposium on Formation Flying Missions and Technologies

Science.gov (United States)

2004-01-01

Topics discussed include: The Stellar Imager (SI) "Vision Mission"; First Formation Flying Demonstration Mission Including on Flight Nulling; Formation Flying X-ray Telescope in L2 Orbit; SPECS: The Kilometer-baseline Far-IR Interferometer in NASA's Space Science Roadmap Presentation; A Tight Formation for Along-track SAR Interferometry; Realization of the Solar Power Satellite using the Formation Flying Solar Reflector; SIMBOL-X : Formation Flying for High-Energy Astrophysics; High Precision Optical Metrology for DARWIN; Close Formation Flight of Micro-Satellites for SAR Interferometry; Station-Keeping Requirements for Astronomical Imaging with Constellations of Free-Flying Collectors; Closed-Loop Control of Formation Flying Satellites; Formation Control for the MAXIM Mission; Precision Formation Keeping at L2 Using the Autonomous Formation Flying Sensor; Robust Control of Multiple Spacecraft Formation Flying; Virtual Rigid Body (VRB) Satellite Formation Control: Stable Mode-Switching and Cross-Coupling; Electromagnetic Formation Flight (EMFF) System Design, Mission Capabilities, and Testbed Development; Navigation Algorithms for Formation Flying Missions; Use of Formation Flying Small Satellites Incorporating OISL's in a Tandem Cluster Mission; Semimajor Axis Estimation Strategies; Relative Attitude Determination of Earth Orbiting Formations Using GPS Receivers; Analysis of Formation Flying in Eccentric Orbits Using Linearized Equations of Relative Motion; Conservative Analytical Collision Probabilities for Orbital Formation Flying; Equations of Motion and Stability of Two Spacecraft in Formation at the Earth/Moon Triangular Libration Points; Formations Near the Libration Points: Design Strategies Using Natural and Non-Natural Ares; An Overview of the Formation and Attitude Control System for the Terrestrial Planet Finder Formation Flying Interferometer; GVE-Based Dynamics and Control for Formation Flying Spacecraft; GNC System Design for a New Concept of X

I spy with my little eye: Analysis of airline pilots' gaze patterns in a manual instrument flight scenario.

Science.gov (United States)

Haslbeck, Andreas; Zhang, Bo

2017-09-01

The aim of this study was to analyze pilots' visual scanning in a manual approach and landing scenario. Manual flying skills suffer from increasing use of automation. In addition, predominantly long-haul pilots with only a few opportunities to practice these skills experience this decline. Airline pilots representing different levels of practice (short-haul vs. long-haul) had to perform a manual raw data precision approach while their visual scanning was recorded by an eye-tracking device. The analysis of gaze patterns, which are based on predominant saccades, revealed one main group of saccades among long-haul pilots. In contrast, short-haul pilots showed more balanced scanning using two different groups of saccades. Short-haul pilots generally demonstrated better manual flight performance and within this group, one type of scan pattern was found to facilitate the manual landing task more. Long-haul pilots tend to utilize visual scanning behaviors that are inappropriate for the manual ILS landing task. This lack of skills needs to be addressed by providing specific training and more practice. Copyright © 2017 Elsevier Ltd. All rights reserved.

A novel attention training paradigm based on operant conditioning of eye gaze: Preliminary findings.

Science.gov (United States)

Price, Rebecca B; Greven, Inez M; Siegle, Greg J; Koster, Ernst H W; De Raedt, Rudi

2016-02-01

Inability to engage with positive stimuli is a widespread problem associated with negative mood states across many conditions, from low self-esteem to anhedonic depression. Though attention retraining procedures have shown promise as interventions in some clinical populations, novel procedures may be necessary to reliably attenuate chronic negative mood in refractory clinical populations (e.g., clinical depression) through, for example, more active, adaptive learning processes. In addition, a focus on individual difference variables predicting intervention outcome may improve the ability to provide such targeted interventions efficiently. To provide preliminary proof-of-principle, we tested a novel paradigm using operant conditioning to train eye gaze patterns toward happy faces. Thirty-two healthy undergraduates were randomized to receive operant conditioning of eye gaze toward happy faces (train-happy) or neutral faces (train-neutral). At the group level, the train-happy condition attenuated sad mood increases following a stressful task, in comparison to train-neutral. In individual differences analysis, greater physiological reactivity (pupil dilation) in response to happy faces (during an emotional face-search task at baseline) predicted decreased mood reactivity after stress. These Preliminary results suggest that operant conditioning of eye gaze toward happy faces buffers against stress-induced effects on mood, particularly in individuals who show sufficient baseline neural engagement with happy faces. Eye gaze patterns to emotional face arrays may have a causal relationship with mood reactivity. Personalized medicine research in depression may benefit from novel cognitive training paradigms that shape eye gaze patterns through feedback. Baseline neural function (pupil dilation) may be a key mechanism, aiding in iterative refinement of this approach. (c) 2016 APA, all rights reserved).

Studying the influence of race on the gaze cueing effect using eye tracking method

Directory of Open Access Journals (Sweden)

Galina Ya. Menshikova

2017-06-01

Full Text Available The gaze direction of another person is an important social cue, allowing us to orient quickly in social interactions. The effect of short-term redirection of visual attention to the same object that other people are looking at is known as the gaze cueing effect. There is evidence that the strength of this effect depends on many social factors, such as the trust in a partner, her/his gender, social attitudes, etc. In our study we investigated the influence of race of face stimuli on the strength of the gaze cueing effect. Using the modified Posner Cueing Task an attentional shift was assessed in a scene where avatar faces of different race were used as distractors. Participants were instructed to fix the black dot in the centre of the screen until it changes colour, and then as soon as possible to make a rightward or leftward saccade, depending on colour of a fixed point. A male distractor face was shown in the centre of the screen simultaneously with a fixed point. The gaze direction of the distractor face changed from straight ahead to rightward or leftward at the moment when colour of a fixed point changed. It could be either congruent or incongruent with the saccade direction. We used face distractors of three race categories: Caucasian (own race faces, Asian and African (other race faces. Twenty five Caucasian participants took part in our study. The results showed that the race of face distractors influence the strength of the gaze cueing effect, that manifested in the change of latency and velocity of the ongoing saccades.

There is more to gaze than meets the eye: How animals perceive the visual behaviour of others

NARCIS (Netherlands)

Goossens, B.M.A.

2008-01-01

Gaze following and the ability to understand that another individual sees something different from oneself are considered important components of human and animal social cognition. In animals, gaze following has been documented in various species, however, the underlying cognitive mechanisms and the

Gaze cuing of attention in snake phobic women: the influence of facial expression

Directory of Open Access Journals (Sweden)

Carolina ePletti

2015-04-01

Full Text Available Only a few studies investigated whether animal phobics exhibit attentional biases in contexts where no phobic stimuli are present. Among these, recent studies provided evidence for a bias toward facial expressions of fear and disgust in animal phobics. Such findings may be due to the fact that these expressions could signal the presence of a phobic object in the surroundings. To test this hypothesis and further investigate attentional biases for emotional faces in animal phobics, we conducted an experiment using a gaze-cuing paradigm in which participants’ attention was driven by the task-irrelevant gaze of a centrally presented face. We employed dynamic negative facial expressions of disgust, fear and anger and found an enhanced gaze-cuing effect in snake phobics as compared to controls, irrespective of facial expression. These results provide evidence of a general hypervigilance in animal phobics in the absence of phobic stimuli, and indicate that research on specific phobias should not be limited to symptom provocation paradigms.

Gaze-independent BCI-spelling using rapid serial visual presentation (RSVP).

Science.gov (United States)

Acqualagna, Laura; Blankertz, Benjamin

2013-05-01

A Brain Computer Interface (BCI) speller is a communication device, which can be used by patients suffering from neurodegenerative diseases to select symbols in a computer application. For patients unable to overtly fixate the target symbol, it is crucial to develop a speller independent of gaze shifts. In the present online study, we investigated rapid serial visual presentation (RSVP) as a paradigm for mental typewriting. We investigated the RSVP speller in three conditions, regarding the Stimulus Onset Asynchrony (SOA) and the use of color features. A vocabulary of 30 symbols was presented one-by-one in a pseudo random sequence at the same location of display. All twelve participants were able to successfully operate the RSVP speller. The results show a mean online spelling rate of 1.43 symb/min and a mean symbol selection accuracy of 94.8% in the best condition. We conclude that the RSVP is a promising paradigm for BCI spelling and its performance is competitive with the fastest gaze-independent spellers in literature. The RSVP speller does not require gaze shifts towards different target locations and can be operated by non-spatial visual attention, therefore it can be considered as a valid paradigm in applications with patients for impaired oculo-motor control. Copyright © 2013 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

Current Methods to Detoxify Fly Ash from Waste Incineration

Energy Technology Data Exchange (ETDEWEB)

Hallgren, Christine; Stroemberg, Birgitta [TPS Termiska Processer AB, Nykoeping (Sweden)

2004-07-01

Fly ash from waste incineration contains large amounts of heavy metals and dioxins, which will cause a significant disposal problem within the coming years. The amount of fly ash produced in Sweden is currently approximately 60,000 tons/y. New technological options for the decontamination and/or inertization of incinerator fly ash are being developed with the objective of rendering a product that can be reused or, at least, be deposited at standard landfill sites with no risk. Many of these technologies have been tested at industrial scale or in pilot projects. The proposed alternatives include: Thermal treatments; Immobilization/stabilization by cement based techniques; Wet chemical treatments (extractions, immobilizations); Microbiological treatments. Of these, thermal treatments are the most promising solution. Depending on the temperature thermal treatments are classified in two main types: 1) low temperature (below 600 deg C) thermal treatments and 2) high temperature (above 1200 deg C) thermal treatments (vitrification). Most dioxins can be successfully destroyed at temperatures up to 400 deg C under oxygen deficient conditions and at temperatures up to 600 deg C under oxidising conditions. However most heavy metals remain in the fly ash after low temperature treatment. At a temperature of 900 deg C most heavy metals can also be removed in a 10% HCl atmosphere by forming volatile metal chlorides (CT-Fluapur process). During vitrification processes the fly ash melts and forms an inert glassy slag. The product does not leach any significant amount of heavy metals and is free from dioxin. The volume of the fly ash is significantly reduced. The product can be land filled at low costs or used as construction material. The properties of the product depend on the cooling process and on additives such as sand, limestone or waste glass. A series of vitrification methods at industrial size or in pilot scale using different furnaces are studied. Among these, plasma

Self compacting concrete incorporating high-volumes of fly ash

Energy Technology Data Exchange (ETDEWEB)

Bouzoubaa, N. [Natural Resources Canada, Ottawa, ON (Canada). International Centre for Sustainable Development of Cement and Concrete; Lachemi, M. [Ryerson Polytechnic Univ., Toronto, ON (Canada). Dept. of Civil Engineering

2004-07-01

Self-compacting concrete (SCC) is now widely used in reinforced concrete structures. Fine materials such as fly ash ensure that the concrete has the necessary properties of high fluidity and cohesiveness. An experimental study was conducted in which 9 SCC mixtures and one control concrete were produced in order to evaluate SCC made with high-volumes of fly ash. The content of the cementitious materials remained constant at 400 kg/cubic metre, but the ratio of water to cementitious material ranged from 0.35 to 0.45. The viscosity and stability of the fresh concrete was determined for self-compacting mixtures of 40, 50 and 60 per cent Class F fly ash. The compressive strength and drying shrinkage were also determined for the hardened concretes. Results showed that the SCCs developed a 28-day compressive strength ranging from 26 to 48 MPa. It was concluded that high-volumes of Class F fly ash could offer the following advantages to an SCC: reduced construction time and labour cost; eliminate the need for vibration; reduce noise pollution; improve the filling capacity of highly congested structural members; and, ensure good structural performance. 19 refs., 8 tabs., 2 figs.

Visual perception during mirror gazing at one's own face in schizophrenia.

Science.gov (United States)

Caputo, Giovanni B; Ferrucci, Roberta; Bortolomasi, Marco; Giacopuzzi, Mario; Priori, Alberto; Zago, Stefano

2012-09-01

In normal observers gazing at one's own face in the mirror for some minutes, at a low illumination level, triggers the perception of strange faces, a new perceptual illusion that has been named 'strange-face in the mirror'. Subjects see distortions of their own faces, but often they see monsters, archetypical faces, faces of dead relatives, and of animals. We designed this study to primarily compare strange-face apparitions in response to mirror gazing in patients with schizophrenia and healthy controls. The study included 16 patients with schizophrenia and 21 healthy controls. In this paper we administered a 7 minute mirror gazing test (MGT). Before the mirror gazing session, all subjects underwent assessment with the Cardiff Anomalous Perception Scale (CAPS). When the 7minute MGT ended, the experimenter assessed patients and controls with a specifically designed questionnaire and interviewed them, asking them to describe strange-face perceptions. Apparitions of strange-faces in the mirror were significantly more intense in schizophrenic patients than in controls. All the following variables were higher in patients than in healthy controls: frequency (p<.005) and cumulative duration of apparitions (p<.009), number and types of strange-faces (p<.002), self-evaluation scores on Likert-type scales of apparition strength (p<.03) and of reality of apparitions (p<.001). In schizophrenic patients, these Likert-type scales showed correlations (p<.05) with CAPS total scores. These results suggest that the increase of strange-face apparitions in schizophrenia can be produced by ego dysfunction, by body dysmorphic disorder and by misattribution of self-agency. MGT may help in completing the standard assessment of patients with schizophrenia, independently of hallucinatory psychopathology. Copyright © 2012 Elsevier B.V. All rights reserved.

The Oxytocin Receptor Gene (OXTR) and gazing behavior during social interaction: An observational study in young adults

NARCIS (Netherlands)

Verhagen, M.; Engels, R.C.M.E.; Roekel, G.H. van

2014-01-01

Background: In the present study, the relation between a polymorphic marker within the OXTR gene (rs53576) and gazing behavior during two separate social interaction tasks was examined. Gazing behavior was considered to be an integral part of belonging regulation processes. Methods: We conducted an

Adaptive Gaze Strategies for Locomotion with Constricted Visual Field

Directory of Open Access Journals (Sweden)

Colas N. Authié

2017-07-01

Full Text Available In retinitis pigmentosa (RP, loss of peripheral visual field accounts for most difficulties encountered in visuo-motor coordination during locomotion. The purpose of this study was to accurately assess the impact of peripheral visual field loss on gaze strategies during locomotion, and identify compensatory mechanisms. Nine RP subjects presenting a central visual field limited to 10–25° in diameter, and nine healthy subjects were asked to walk in one of three directions—straight ahead to a visual target, leftward and rightward through a door frame, with or without obstacle on the way. Whole body kinematics were recorded by motion capture, and gaze direction in space was reconstructed using an eye-tracker. Changes in gaze strategies were identified in RP subjects, including extensive exploration prior to walking, frequent fixations of the ground (even knowing no obstacle was present, of door edges, essentially of the proximal one, of obstacle edge/corner, and alternating door edges fixations when approaching the door. This was associated with more frequent, sometimes larger rapid-eye-movements, larger movements, and forward tilting of the head. Despite the visual handicap, the trajectory geometry was identical between groups, with a small decrease in walking speed in RPs. These findings identify the adaptive changes in sensory-motor coordination, in order to ensure visual awareness of the surrounding, detect changes in spatial configuration, collect information for self-motion, update the postural reference frame, and update egocentric distances to environmental objects. They are of crucial importance for the design of optimized rehabilitation procedures.

Adaptive Gaze Strategies for Locomotion with Constricted Visual Field

Science.gov (United States)

Authié, Colas N.; Berthoz, Alain; Sahel, José-Alain; Safran, Avinoam B.

2017-01-01

In retinitis pigmentosa (RP), loss of peripheral visual field accounts for most difficulties encountered in visuo-motor coordination during locomotion. The purpose of this study was to accurately assess the impact of peripheral visual field loss on gaze strategies during locomotion, and identify compensatory mechanisms. Nine RP subjects presenting a central visual field limited to 10–25° in diameter, and nine healthy subjects were asked to walk in one of three directions—straight ahead to a visual target, leftward and rightward through a door frame, with or without obstacle on the way. Whole body kinematics were recorded by motion capture, and gaze direction in space was reconstructed using an eye-tracker. Changes in gaze strategies were identified in RP subjects, including extensive exploration prior to walking, frequent fixations of the ground (even knowing no obstacle was present), of door edges, essentially of the proximal one, of obstacle edge/corner, and alternating door edges fixations when approaching the door. This was associated with more frequent, sometimes larger rapid-eye-movements, larger movements, and forward tilting of the head. Despite the visual handicap, the trajectory geometry was identical between groups, with a small decrease in walking speed in RPs. These findings identify the adaptive changes in sensory-motor coordination, in order to ensure visual awareness of the surrounding, detect changes in spatial configuration, collect information for self-motion, update the postural reference frame, and update egocentric distances to environmental objects. They are of crucial importance for the design of optimized rehabilitation procedures. PMID:28798674

How do we update faces? Effects of gaze direction and facial expressions on working memory updating

Directory of Open Access Journals (Sweden)

Caterina eArtuso

2012-09-01

Full Text Available The aim of the study was to investigate how the biological binding between different facial dimensions, and their social and communicative relevance, may impact updating processes in working memory (WM. We focused on WM updating because it plays a key role in ongoing processing. Gaze direction and facial expression are crucial and changeable components of face processing. Direct gaze enhances the processing of approach-oriented facial emotional expressions (e.g. joy, while averted gaze enhances the processing of avoidance-oriented facial emotional expressions (e.g. fear. Thus, the way in which these two facial dimensions are combined communicates to the observer important behavioral and social information. Updating of these two facial dimensions and their bindings has not been investigated before, despite the fact that they provide a piece of social information essential for building and maintaining an internal ongoing representation of our social environment. In Experiment 1 we created a task in which the binding between gaze direction and facial expression was manipulated: high binding conditions (e.g. joy-direct gaze were compared to low binding conditions (e.g. joy-averted gaze. Participants had to study and update continuously a number of faces, displaying different bindings between the two dimensions. In Experiment 2 we tested whether updating was affected by the social and communicative value of the facial dimension binding; to this end, we manipulated bindings between eye and hair color, two less communicative facial dimensions. Two new results emerged. First, faster response times were found in updating combinations of facial dimensions highly bound together. Second, our data showed that the ease of the ongoing updating processing varied depending on the communicative meaning of the binding that had to be updated. The results are discussed with reference to the role of WM updating in social cognition and appraisal processes.

How do we update faces? Effects of gaze direction and facial expressions on working memory updating.

Science.gov (United States)

Artuso, Caterina; Palladino, Paola; Ricciardelli, Paola

2012-01-01

The aim of the study was to investigate how the biological binding between different facial dimensions, and their social and communicative relevance, may impact updating processes in working memory (WM). We focused on WM updating because it plays a key role in ongoing processing. Gaze direction and facial expression are crucial and changeable components of face processing. Direct gaze enhances the processing of approach-oriented facial emotional expressions (e.g., joy), while averted gaze enhances the processing of avoidance-oriented facial emotional expressions (e.g., fear). Thus, the way in which these two facial dimensions are combined communicates to the observer important behavioral and social information. Updating of these two facial dimensions and their bindings has not been investigated before, despite the fact that they provide a piece of social information essential for building and maintaining an internal ongoing representation of our social environment. In Experiment 1 we created a task in which the binding between gaze direction and facial expression was manipulated: high binding conditions (e.g., joy-direct gaze) were compared to low binding conditions (e.g., joy-averted gaze). Participants had to study and update continuously a number of faces, displaying different bindings between the two dimensions. In Experiment 2 we tested whether updating was affected by the social and communicative value of the facial dimension binding; to this end, we manipulated bindings between eye and hair color, two less communicative facial dimensions. Two new results emerged. First, faster response times were found in updating combinations of facial dimensions highly bound together. Second, our data showed that the ease of the ongoing updating processing varied depending on the communicative meaning of the binding that had to be updated. The results are discussed with reference to the role of WM updating in social cognition and appraisal processes.

Self-Monitoring of Gaze in High Functioning Autism

Science.gov (United States)

Grynszpan, Ouriel; Nadel, Jacqueline; Martin, Jean-Claude; Simonin, Jerome; Bailleul, Pauline; Wang, Yun; Gepner, Daniel; Le Barillier, Florence; Constant, Jacques

2012-01-01

Atypical visual behaviour has been recently proposed to account for much of social misunderstanding in autism. Using an eye-tracking system and a gaze-contingent lens display, the present study explores self-monitoring of eye motion in two conditions: free visual exploration and guided exploration via blurring the visual field except for the focal…

Cortical Activation during Landmark-Centered vs. Gaze-Centered Memory of Saccade Targets in the Human: An FMRI Study

Directory of Open Access Journals (Sweden)

Ying Chen

2017-06-01

Full Text Available A remembered saccade target could be encoded in egocentric coordinates such as gaze-centered, or relative to some external allocentric landmark that is independent of the target or gaze (landmark-centered. In comparison to egocentric mechanisms, very little is known about such a landmark-centered representation. Here, we used an event-related fMRI design to identify brain areas supporting these two types of spatial coding (i.e., landmark-centered vs. gaze-centered for target memory during the Delay phase where only target location, not saccade direction, was specified. The paradigm included three tasks with identical display of visual stimuli but different auditory instructions: Landmark Saccade (remember target location relative to a visual landmark, independent of gaze, Control Saccade (remember original target location relative to gaze fixation, independent of the landmark, and a non-spatial control, Color Report (report target color. During the Delay phase, the Control and Landmark Saccade tasks activated overlapping areas in posterior parietal cortex (PPC and frontal cortex as compared to the color control, but with higher activation in PPC for target coding in the Control Saccade task and higher activation in temporal and occipital cortex for target coding in Landmark Saccade task. Gaze-centered directional selectivity was observed in superior occipital gyrus and inferior occipital gyrus, whereas landmark-centered directional selectivity was observed in precuneus and midposterior intraparietal sulcus. During the Response phase after saccade direction was specified, the parietofrontal network in the left hemisphere showed higher activation for rightward than leftward saccades. Our results suggest that cortical activation for coding saccade target direction relative to a visual landmark differs from gaze-centered directional selectivity for target memory, from the mechanisms for other types of allocentric tasks, and from the directionally

The effect of arousal and eye gaze direction on trust evaluations of stranger's faces: A potential pathway to paranoid thinking.

Science.gov (United States)

Abbott, Jennie; Middlemiss, Megan; Bruce, Vicki; Smailes, David; Dudley, Robert

2018-09-01

When asked to evaluate faces of strangers, people with paranoia show a tendency to rate others as less trustworthy. The present study investigated the impact of arousal on this interpersonal bias, and whether this bias was specific to evaluations of trust or additionally affected other trait judgements. The study also examined the impact of eye gaze direction, as direct eye gaze has been shown to heighten arousal. In two experiments, non-clinical participants completed face rating tasks before and after either an arousal manipulation or control manipulation. Experiment one examined the effects of heightened arousal on judgements of trustworthiness. Experiment two examined the specificity of the bias, and the impact of gaze direction. Experiment one indicated that the arousal manipulation led to lower trustworthiness ratings. Experiment two showed that heightened arousal reduced trust evaluations of trustworthy faces, particularly trustworthy faces with averted gaze. The control group rated trustworthy faces with direct gaze as more trustworthy post-manipulation. There was some evidence that attractiveness ratings were affected similarly to the trust judgements, whereas judgements of intelligence were not affected by higher arousal. In both studies, participants reported low levels of arousal even after the manipulation and the use of a non-clinical sample limits the generalisability to clinical samples. There is a complex interplay between arousal, evaluations of trustworthiness and gaze direction. Heightened arousal influences judgements of trustworthiness, but within the context of face type and gaze direction. Copyright © 2018 Elsevier Ltd. All rights reserved.

WOMAN AS OBJECT OF MALE GAZE IN SOME WORKS OF ...

African Journals Online (AJOL)

Nkiruka

marketing and sale of the product, but also an object of male gaze. ... Edward Manet, whose painting Olympia, thought to be inspired by Titian‟s ... encountered in Western art history, whereas unidentifiable nude males were infrequently.

EyeDroid: An Open Source Mobile Gaze Tracker on Android for Eyewear Computers

DEFF Research Database (Denmark)

Jalaliniya, Shahram; Mardanbeigi, Diako; Sintos, Ioannis

2015-01-01

In this paper we report on development and evaluation of a video-based mobile gaze tracker for eyewear computers. Unlike most of the previous work, our system performs all its processing workload on an Android device and sends the coordinates of the gaze point to an eyewear device through wireless...... connection. We propose a lightweight software architecture for Android to increase the efficiency of image processing needed for eye tracking. The evaluation of the system indicated an accuracy of 1:06 and a battery lifetime of approximate 4.5 hours....

Keeping Your Eye on the Rail: Gaze Behaviour of Horse Riders Approaching a Jump

Science.gov (United States)

Hall, Carol; Varley, Ian; Kay, Rachel; Crundall, David

2014-01-01

The gaze behaviour of riders during their approach to a jump was investigated using a mobile eye tracking device (ASL Mobile Eye). The timing, frequency and duration of fixations on the jump and the percentage of time when their point of gaze (POG) was located elsewhere were assessed. Fixations were identified when the POG remained on the jump for 100 ms or longer. The jumping skill of experienced but non-elite riders (n = 10) was assessed by means of a questionnaire. Their gaze behaviour was recorded as they completed a course of three identical jumps five times. The speed and timing of the approach was calculated. Gaze behaviour throughout the overall approach and during the last five strides before take-off was assessed following frame-by-frame analyses. Differences in relation to both round and jump number were found. Significantly longer was spent fixated on the jump during round 2, both during the overall approach and during the last five strides (pJump 1 was fixated on significantly earlier and more frequently than jump 2 or 3 (pjump 3 than with jump 1 (p = 0.01) but there was no difference in errors made between rounds. Although no significant correlations between gaze behaviour and skill scores were found, the riders who scored higher for jumping skill tended to fixate on the jump earlier (p = 0.07), when the horse was further from the jump (p = 0.09) and their first fixation on the jump was of a longer duration (p = 0.06). Trials with elite riders are now needed to further identify sport-specific visual skills and their relationship with performance. Visual training should be included in preparation for equestrian sports participation, the positive impact of which has been clearly demonstrated in other sports. PMID:24846055

Altered attentional and perceptual processes as indexed by N170 during gaze perception in schizophrenia: Relationship with perceived threat and paranoid delusions.

Science.gov (United States)

Tso, Ivy F; Calwas, Anita M; Chun, Jinsoo; Mueller, Savanna A; Taylor, Stephan F; Deldin, Patricia J

2015-08-01

Using gaze information to orient attention and guide behavior is critical to social adaptation. Previous studies have suggested that abnormal gaze perception in schizophrenia (SCZ) may originate in abnormal early attentional and perceptual processes and may be related to paranoid symptoms. Using event-related brain potentials (ERPs), this study investigated altered early attentional and perceptual processes during gaze perception and their relationship to paranoid delusions in SCZ. Twenty-eight individuals with SCZ or schizoaffective disorder and 32 demographically matched healthy controls (HCs) completed a gaze-discrimination task with face stimuli varying in gaze direction (direct, averted), head orientation (forward, deviated), and emotion (neutral, fearful). ERPs were recorded during the task. Participants rated experienced threat from each face after the task. Participants with SCZ were as accurate as, though slower than, HCs on the task. Participants with SCZ displayed enlarged N170 responses over the left hemisphere to averted gaze presented in fearful relative to neutral faces, indicating a heightened encoding sensitivity to faces signaling external threat. This abnormality was correlated with increased perceived threat and paranoid delusions. Participants with SCZ also showed a reduction of N170 modulation by head orientation (normally increased amplitude to deviated faces relative to forward faces), suggesting less integration of contextual cues of head orientation in gaze perception. The psychophysiological deviations observed during gaze discrimination in SCZ underscore the role of early attentional and perceptual abnormalities in social information processing and paranoid symptoms of SCZ. (c) 2015 APA, all rights reserved).

Depth Compensation Model for Gaze Estimation in Sport Analysis

DEFF Research Database (Denmark)

Batista Narcizo, Fabricio; Hansen, Dan Witzner

2015-01-01

is tested in a totally controlled environment with aim to check the influences of eye tracker parameters and ocular biometric parameters on its behavior. We also present a gaze estimation method based on epipolar geometry for binocular eye tracking setups. The depth compensation model has shown very...

The Benslimane's Artistic Model for Females' Gaze Beauty: An Original Assessment Tool.

Science.gov (United States)

Benslimane, Fahd; van Harpen, Laura; Myers, Simon R; Ingallina, Fabio; Ghanem, Ali M

2017-02-01

The aim of this paper is to analyze the aesthetic characteristics of the human females' gaze using anthropometry and to present an artistic model to represent it: "The Frame Concept." In this model, the eye fissure represents a painting, and the most peripheral shadows around it represent the frame of this painting. The narrower the frame, the more aesthetically pleasing and youthful the gaze appears. This study included a literature review of the features that make the gaze appear attractive. Photographs of models with attractive gazes were examined, and old photographs of patients were compared to recent photographs. The frame ratio was defined by anthropometric measurements of modern portraits of twenty consecutive Miss World winners. The concept was then validated for age and attractiveness across centuries by analysis of modern female photographs and works of art acknowledged for portraying beautiful young and older women in classical paintings. The frame height inversely correlated with attractiveness in modern female portrait photographs. The eye fissure frame ratio of modern idealized female portraits was similar to that of beautiful female portraits idealized by classical artists. In contrast, the eye fissure frames of classical artists' mothers' portraits were significantly wider than those of beautiful younger women. The Frame Concept is a valid artistic tool that provides an understanding of both the aesthetic and aging characteristics of the female periorbital region, enabling the practitioner to plan appropriate aesthetic interventions. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the A3 online Instructions to Authors. www.springer.com/00266 .

DIAGNOSIS OF MYASTHENIA GRAVIS USING FUZZY GAZE TRACKING SOFTWARE

Directory of Open Access Journals (Sweden)

Javad Rasti

2015-04-01

Full Text Available Myasthenia Gravis (MG is an autoimmune disorder, which may lead to paralysis and even death if not treated on time. One of its primary symptoms is severe muscular weakness, initially arising in the eye muscles. Testing the mobility of the eyeball can help in early detection of MG. In this study, software was designed to analyze the ability of the eye muscles to focus in various directions, thus estimating the MG risk. Progressive weakness in gazing at the directions prompted by the software can reveal abnormal fatigue of the eye muscles, which is an alert sign for MG. To assess the user’s ability to keep gazing at a specified direction, a fuzzy algorithm was applied to images of the user’s eyes to determine the position of the iris in relation to the sclera. The results of the tests performed on 18 healthy volunteers and 18 volunteers in early stages of MG confirmed the validity of the suggested software.

Using Variable Dwell Time to Accelerate Gaze-based Web Browsing with Two-step Selection

OpenAIRE

Chen, Zhaokang; Shi, Bertram E.

2017-01-01

In order to avoid the "Midas Touch" problem, gaze-based interfaces for selection often introduce a dwell time: a fixed amount of time the user must fixate upon an object before it is selected. Past interfaces have used a uniform dwell time across all objects. Here, we propose an algorithm for adjusting the dwell times of different objects based on the inferred probability that the user intends to select them. In particular, we introduce a probabilistic model of natural gaze behavior while sur...

Stability and leaching of cobalt smelter fly ash

DEFF Research Database (Denmark)

Vítková, Martina; Hyks, Jiri; Ettler, Vojtěch

2013-01-01

The leaching behaviour of fly ash from a Co smelter situated in the Zambian Copperbelt was studied as a function of pH (5–12) using the pH-static leaching test (CEN/TS 14997). Various experimental time intervals (48h and 168h) were evaluated. The leaching results were combined with the ORCHESTRA...... modelling framework and a detailed mineralogical investigation was performed on the original FA and leached solid residues. The largest amounts of Co, Cu, Pb and Zn were leached at pH 5, generally with the lowest concentrations between pH 9 and 11 and slightly increased concentrations at pH 12. For most...... detected using SEM/EDS and/or TEM/EDS. The leaching of metals was mainly attributed to the dissolution of metallic particles. Partial dissolution of silicate and glass fractions was assumed to significantly influence the release of Ca, Mg, Fe, K, Al and Si as well as Cu, Co and Zn. The formation of illite...

Social communication with virtual agents: The effects of body and gaze direction on attention and emotional responding in human observers.

Science.gov (United States)

Marschner, Linda; Pannasch, Sebastian; Schulz, Johannes; Graupner, Sven-Thomas

2015-08-01

In social communication, the gaze direction of other persons provides important information to perceive and interpret their emotional response. Previous research investigated the influence of gaze by manipulating mutual eye contact. Therefore, gaze and body direction have been changed as a whole, resulting in only congruent gaze and body directions (averted or directed) of another person. Here, we aimed to disentangle these effects by using short animated sequences of virtual agents posing with either direct or averted body or gaze. Attention allocation by means of eye movements, facial muscle response, and emotional experience to agents of different gender and facial expressions were investigated. Eye movement data revealed longer fixation durations, i.e., a stronger allocation of attention, when gaze and body direction were not congruent with each other or when both were directed towards the observer. This suggests that direct interaction as well as incongruous signals increase the demands of attentional resources in the observer. For the facial muscle response, only the reaction of muscle zygomaticus major revealed an effect of body direction, expressed by stronger activity in response to happy expressions for direct compared to averted gaze when the virtual character's body was directed towards the observer. Finally, body direction also influenced the emotional experience ratings towards happy expressions. While earlier findings suggested that mutual eye contact is the main source for increased emotional responding and attentional allocation, the present results indicate that direction of the virtual agent's body and head also plays a minor but significant role. Copyright © 2015 Elsevier B.V. All rights reserved.

3D gaze tracking system for NVidia 3D Vision®.

Science.gov (United States)

Wibirama, Sunu; Hamamoto, Kazuhiko

2013-01-01

Inappropriate parallax setting in stereoscopic content generally causes visual fatigue and visual discomfort. To optimize three dimensional (3D) effects in stereoscopic content by taking into account health issue, understanding how user gazes at 3D direction in virtual space is currently an important research topic. In this paper, we report the study of developing a novel 3D gaze tracking system for Nvidia 3D Vision(®) to be used in desktop stereoscopic display. We suggest an optimized geometric method to accurately measure the position of virtual 3D object. Our experimental result shows that the proposed system achieved better accuracy compared to conventional geometric method by average errors 0.83 cm, 0.87 cm, and 1.06 cm in X, Y, and Z dimensions, respectively.

Evaluation of robustness of fly ash stabilized sewage sludge (FSS) as liner - Durability, percolation and drainage water quality; Bedoemning av laangtidsegenskaper hos taetskikt bestaaende av flygaskastabiliserat avloppsslam, FSA - Bestaendighet, taethet och ytutlakning

Energy Technology Data Exchange (ETDEWEB)

Macsik, Josef; Laendell, Maerta; Haakansson, Karsten

2012-02-15

This project shows that fly ash stabilized sewage sludge (FSS) is watertight and resistant as liner in landfills. The presented results can lead to that more landfills will use FSS as liner, and landfills already using FSS together with geomembrane, can leave out the latter without risking contamination of the drainage water collected by the closure construction

Prior Knowledge Facilitates Mutual Gaze Convergence and Head Nodding Synchrony in Face-to-face Communication.

Science.gov (United States)

Thepsoonthorn, C; Yokozuka, T; Miura, S; Ogawa, K; Miyake, Y

2016-12-02

As prior knowledge is claimed to be an essential key to achieve effective education, we are interested in exploring whether prior knowledge enhances communication effectiveness. To demonstrate the effects of prior knowledge, mutual gaze convergence and head nodding synchrony are observed as indicators of communication effectiveness. We conducted an experiment on lecture task between lecturer and student under 2 conditions: prior knowledge and non-prior knowledge. The students in prior knowledge condition were provided the basic information about the lecture content and were assessed their understanding by the experimenter before starting the lecture while the students in non-prior knowledge had none. The result shows that the interaction in prior knowledge condition establishes significantly higher mutual gaze convergence (t(15.03) = 6.72, p < 0.0001; α = 0.05, n = 20) and head nodding synchrony (t(16.67) = 1.83, p = 0.04; α = 0.05, n = 19) compared to non-prior knowledge condition. This study reveals that prior knowledge facilitates mutual gaze convergence and head nodding synchrony. Furthermore, the interaction with and without prior knowledge can be evaluated by measuring or observing mutual gaze convergence and head nodding synchrony.

Seeing to hear? Patterns of gaze to speaking faces in children with autism spectrum disorders.

Directory of Open Access Journals (Sweden)

Julia eIrwin

2014-05-01

Full Text Available Using eye-tracking methodology, gaze to a speaking face was compared in a group of children with autism spectrum disorders (ASD and those with typical development (TD. Patterns of gaze were observed under three conditions: audiovisual (AV speech in auditory noise, visual only speech and an AV non-face, non-speech control. Children with ASD looked less to the face of the speaker and fixated less on the speakers’ mouth than TD controls. No differences in gaze were reported for the non-face, non-speech control task. Since the mouth holds much of the articulatory information available on the face, these findings suggest that children with ASD may have reduced access to critical linguistic information. This reduced access to visible articulatory information could be a contributor to the communication and language problems exhibited by children with ASD.

Postural sway and gaze can track the complex motion of a visual target.

Directory of Open Access Journals (Sweden)

Vassilia Hatzitaki

Full Text Available Variability is an inherent and important feature of human movement. This variability has form exhibiting a chaotic structure. Visual feedback training using regular predictive visual target motions does not take into account this essential characteristic of the human movement, and may result in task specific learning and loss of visuo-motor adaptability. In this study, we asked how well healthy young adults can track visual target cues of varying degree of complexity during whole-body swaying in the Anterior-Posterior (AP and Medio-Lateral (ML direction. Participants were asked to track three visual target motions: a complex (Lorenz attractor, a noise (brown and a periodic (sine moving target while receiving online visual feedback about their performance. Postural sway, gaze and target motion were synchronously recorded and the degree of force-target and gaze-target coupling was quantified using spectral coherence and Cross-Approximate entropy. Analysis revealed that both force-target and gaze-target coupling was sensitive to the complexity of the visual stimuli motions. Postural sway showed a higher degree of coherence with the Lorenz attractor than the brown noise or sinusoidal stimulus motion. Similarly, gaze was more synchronous with the Lorenz attractor than the brown noise and sinusoidal stimulus motion. These results were similar regardless of whether tracking was performed in the AP or ML direction. Based on the theoretical model of optimal movement variability tracking of a complex signal may provide a better stimulus to improve visuo-motor adaptation and learning in postural control.

Interacting with target tracking algorithms in a gaze-enhanced motion video analysis system

Science.gov (United States)

Hild, Jutta; Krüger, Wolfgang; Heinze, Norbert; Peinsipp-Byma, Elisabeth; Beyerer, Jürgen

2016-05-01

Motion video analysis is a challenging task, particularly if real-time analysis is required. It is therefore an important issue how to provide suitable assistance for the human operator. Given that the use of customized video analysis systems is more and more established, one supporting measure is to provide system functions which perform subtasks of the analysis. Recent progress in the development of automated image exploitation algorithms allow, e.g., real-time moving target tracking. Another supporting measure is to provide a user interface which strives to reduce the perceptual, cognitive and motor load of the human operator for example by incorporating the operator's visual focus of attention. A gaze-enhanced user interface is able to help here. This work extends prior work on automated target recognition, segmentation, and tracking algorithms as well as about the benefits of a gaze-enhanced user interface for interaction with moving targets. We also propose a prototypical system design aiming to combine both the qualities of the human observer's perception and the automated algorithms in order to improve the overall performance of a real-time video analysis system. In this contribution, we address two novel issues analyzing gaze-based interaction with target tracking algorithms. The first issue extends the gaze-based triggering of a target tracking process, e.g., investigating how to best relaunch in the case of track loss. The second issue addresses the initialization of tracking algorithms without motion segmentation where the operator has to provide the system with the object's image region in order to start the tracking algorithm.

Cementing Efficiency of Low Calcium Fly Ash in Fly Ash Concretes

OpenAIRE

T. D. Gunneswara Rao; Mudimby Andal

2014-01-01

Research on the utilization of fly ash will no longer refer the fly ash as a waste material of thermal power plants. Use of fly ash in concrete making, makes the concrete economical as well as durable. The fly ash is being added to the concrete in three ways namely, as partial replacement to cement, as partial replacement to fine aggregates and as admixture. Addition of fly ash to the concrete in any one of the form mentioned above, makes the concrete more workable and durable than the conven...

Quality control of geological voxel models using experts' gaze

NARCIS (Netherlands)

Maanen, P.P. van; Busschers, F.S.; Brouwer, A.M.; Meulen, M.J. van der; Erp, J.B.F. van

2015-01-01

Due to an expected increase in geological voxel model data-flow and user demands, the development of improved quality control for such models is crucial. This study explores the potential of a new type of quality control that improves the detection of errors by just using gaze behavior of 12

Quality Control of Geological Voxel Models using Experts' Gaze

NARCIS (Netherlands)

van Maanen, Peter-Paul; Busschers, Freek S.; Brouwer, Anne-Marie; van der Meulendijk, Michiel J.; van Erp, Johannes Bernardus Fransiscus

Due to an expected increase in geological voxel model data-flow and user demands, the development of improved quality control for such models is crucial. This study explores the potential of a new type of quality control that improves the detection of errors by just using gaze behavior of 12

Reuse of municipal solid wastes incineration fly ashes in concrete mixtures.

Science.gov (United States)

Collivignarelli, Carlo; Sorlini, Sabrina

2002-01-01

This study is aimed at assessing the feasibility of concrete production using stabilized m.s.w. (municipal solid waste) incineration fly ashes in addition to natural aggregates. The tested fly ashes were washed and milled, then stabilized by a cement-lime process and finally were reused as a "recycled aggregate" for cement mixture production, in substitution of a natural aggregate (with dosage of 200-400 kg m(-3)). These mixtures, after curing, were characterized with conventional physical-mechanical tests (compression, traction, flexure, modulus of elasticity, shrinkage). In samples containing 200 kg(waste) m(-3)(concrete), a good compressive strength was achieved after 28 days of curing. Furthermore, concrete leaching behavior was evaluated by means of different leaching tests, both on milled and on monolithic samples. Experimental results showed a remarkable reduction of metal leaching in comparison with raw waste. In some cases, similar behavior was observed in "natural" concrete (produced with natural aggregates) and in "waste containing" concrete.

Look at my poster! Active gaze, preference and memory during a poster session.

Science.gov (United States)

Foulsham, Tom; Kingstone, Alan

2011-01-01

In science, as in advertising, people often present information on a poster, yet little is known about attention during a poster session. A mobile eye-tracker was used to record participants' gaze during a mock poster session featuring a range of academic psychology posters. Participants spent the most time looking at introductions and conclusions. Larger posters were looked at for longer, as were posters rated more interesting (but not necessarily more aesthetically pleasing). Interestingly, gaze did not correlate with memory for poster details or liking, suggesting that attracting someone towards your poster may not be enough.

Laboratory evaluation of fly ash treated embankment and base materials : final report.

Science.gov (United States)

1988-04-01

This study was undertaken to provide the Louisiana DOTD with a data base from which recommendations can be made concerning the modification or stabilization of soils using a Class C fly ash as a full or partial replacement for hydraulic cement or hyd...

When What You See Is What You Get: The Consequences of the Objectifying Gaze for Women and Men

Science.gov (United States)

Gervais, Sarah J.; Vescio, Theresa K.; Allen, Jill

2011-01-01

This research examined the effects of the objectifying gaze on math performance, interaction motivation, body surveillance, body shame, and body dissatisfaction. In an experiment, undergraduate participants (67 women and 83 men) received an objectifying gaze during an interaction with a trained confederate of the other sex. As hypothesized, the…

Optic flow stabilizes flight in ruby-throated hummingbirds.

Science.gov (United States)

Ros, Ivo G; Biewener, Andrew A

2016-08-15

Flying birds rely on visual cues for retinal image stabilization by negating rotation-induced optic flow, the motion of the visual panorama across the retina, through corrective eye and head movements. In combination with vestibular and proprioceptive feedback, birds may also use visual cues to stabilize their body during flight. Here, we test whether artificially induced wide-field motion generated through projected visual patterns elicits maneuvers in body orientation and flight position, in addition to stabilizing vision. To test this hypothesis, we present hummingbirds flying freely within a 1.2 m cylindrical visual arena with a virtual surround rotated at different speeds about its vertical axis. The birds responded robustly to these visual perturbations by rotating their heads and bodies with the moving visual surround, and by adjusting their flight trajectories, following the surround. Thus, similar to insects, hummingbirds appear to use optic flow cues to control flight maneuvers as well as to stabilize their visual inputs. © 2016. Published by The Company of Biologists Ltd.

On-the-fly reduction of open loops

Energy Technology Data Exchange (ETDEWEB)

Buccioni, Federico; Pozzorini, Stefano; Zoller, Max [Universitaet Zuerich, Physik-Institut, Zurich (Switzerland)

2018-01-15

Building on the open-loop algorithm we introduce a new method for the automated construction of one-loop amplitudes and their reduction to scalar integrals. The key idea is that the factorisation of one-loop integrands in a product of loop segments makes it possible to perform various operations on-the-fly while constructing the integrand. Reducing the integrand on-the-fly, after each segment multiplication, the construction of loop diagrams and their reduction are unified in a single numerical recursion. In this way we entirely avoid objects with high tensor rank, thereby reducing the complexity of the calculations in a drastic way. Thanks to the on-the-fly approach, which is applied also to helicity summation and for the merging of different diagrams, the speed of the original open-loop algorithm can be further augmented in a very significant way. Moreover, addressing spurious singularities of the employed reduction identities by means of simple expansions in rank-two Gram determinants, we achieve a remarkably high level of numerical stability. These features of the new algorithm, which will be made publicly available in a forthcoming release of the OpenLoops program, are particularly attractive for NLO multi-leg and NNLO real-virtual calculations. (orig.)

On-the-fly reduction of open loops

Science.gov (United States)

Buccioni, Federico; Pozzorini, Stefano; Zoller, Max

2018-01-01

Building on the open-loop algorithm we introduce a new method for the automated construction of one-loop amplitudes and their reduction to scalar integrals. The key idea is that the factorisation of one-loop integrands in a product of loop segments makes it possible to perform various operations on-the-fly while constructing the integrand. Reducing the integrand on-the-fly, after each segment multiplication, the construction of loop diagrams and their reduction are unified in a single numerical recursion. In this way we entirely avoid objects with high tensor rank, thereby reducing the complexity of the calculations in a drastic way. Thanks to the on-the-fly approach, which is applied also to helicity summation and for the merging of different diagrams, the speed of the original open-loop algorithm can be further augmented in a very significant way. Moreover, addressing spurious singularities of the employed reduction identities by means of simple expansions in rank-two Gram determinants, we achieve a remarkably high level of numerical stability. These features of the new algorithm, which will be made publicly available in a forthcoming release of the OpenLoops program, are particularly attractive for NLO multi-leg and NNLO real-virtual calculations.

Differences in gaze behaviour of expert and junior surgeons performing open inguinal hernia repair.

Science.gov (United States)

Tien, Tony; Pucher, Philip H; Sodergren, Mikael H; Sriskandarajah, Kumuthan; Yang, Guang-Zhong; Darzi, Ara

2015-02-01

Various fields have used gaze behaviour to evaluate task proficiency. This may also apply to surgery for the assessment of technical skill, but has not previously been explored in live surgery. The aim was to assess differences in gaze behaviour between expert and junior surgeons during open inguinal hernia repair. Gaze behaviour of expert and junior surgeons (defined by operative experience) performing the operation was recorded using eye-tracking glasses (SMI Eye Tracking Glasses 2.0, SensoMotoric Instruments, Germany). Primary endpoints were fixation frequency (steady eye gaze rate) and dwell time (fixation and saccades duration) and were analysed for designated areas of interest in the subject's visual field. Secondary endpoints were maximum pupil size, pupil rate of change (change frequency in pupil size) and pupil entropy (predictability of pupil change). NASA TLX scale measured perceived workload. Recorded metrics were compared between groups for the entire procedure and for comparable procedural segments. Twenty-five cases were recorded, with 13 operations analysed, from 9 surgeons giving 630 min of data, recorded at 30 Hz. Experts demonstrated higher fixation frequency (median[IQR] 1.86 [0.3] vs 0.96 [0.3]; P = 0.006) and dwell time on the operative site during application of mesh (792 [159] vs 469 [109] s; P = 0.028), closure of the external oblique (1.79 [0.2] vs 1.20 [0.6]; P = 0.003) (625 [154] vs 448 [147] s; P = 0.032) and dwelled more on the sterile field during cutting of mesh (716 [173] vs 268 [297] s; P = 0.019). NASA TLX scores indicated experts found the procedure less mentally demanding than juniors (3 [2] vs 12 [5.2]; P = 0.038). No subjects reported problems with wearing of the device, or obstruction of view. Use of portable eye-tracking technology in open surgery is feasible, without impinging surgical performance. Differences in gaze behaviour during open inguinal hernia repair can be seen between expert and junior surgeons and may have

Attention, Exposure Duration, and Gaze Shifting in Naming Performance

Science.gov (United States)

Roelofs, Ardi

2011-01-01

Two experiments are reported in which the role of attribute exposure duration in naming performance was examined by tracking eye movements. Participants were presented with color-word Stroop stimuli and left- or right-pointing arrows on different sides of a computer screen. They named the color attribute and shifted their gaze to the arrow to…

The EyeHarp: A Gaze-Controlled Digital Musical Instrument.

Science.gov (United States)

Vamvakousis, Zacharias; Ramirez, Rafael

2016-01-01

We present and evaluate the EyeHarp, a new gaze-controlled Digital Musical Instrument, which aims to enable people with severe motor disabilities to learn, perform, and compose music using only their gaze as control mechanism. It consists of (1) a step-sequencer layer, which serves for constructing chords/arpeggios, and (2) a melody layer, for playing melodies and changing the chords/arpeggios. We have conducted a pilot evaluation of the EyeHarp involving 39 participants with no disabilities from both a performer and an audience perspective. In the first case, eight people with normal vision and no motor disability participated in a music-playing session in which both quantitative and qualitative data were collected. In the second case 31 people qualitatively evaluated the EyeHarp in a concert setting consisting of two parts: a solo performance part, and an ensemble (EyeHarp, two guitars, and flute) performance part. The obtained results indicate that, similarly to traditional music instruments, the proposed digital musical instrument has a steep learning curve, and allows to produce expressive performances both from the performer and audience perspective.

Parent Perception of Two Eye-Gaze Control Technology Systems in Young Children with Cerebral Palsy: Pilot Study.

Science.gov (United States)

Karlsson, Petra; Wallen, Margaret

2017-01-01

Eye-gaze control technology enables people with significant physical disability to access computers for communication, play, learning and environmental control. This pilot study used a multiple case study design with repeated baseline assessment and parents' evaluations to compare two eye-gaze control technology systems to identify any differences in factors such as ease of use and impact of the systems for their young children. Five children, aged 3 to 5 years, with dyskinetic cerebral palsy, and their families participated. Overall, families were satisfied with both the Tobii PCEye Go and myGaze® eye tracker, found them easy to position and use, and children learned to operate them quickly. This technology provides young children with important opportunities for learning, play, leisure, and developing communication.

Goats display audience-dependent human-directed gazing behaviour in a problem-solving task.

Science.gov (United States)

Nawroth, Christian; Brett, Jemma M; McElligott, Alan G

2016-07-01

Domestication is an important factor driving changes in animal cognition and behaviour. In particular, the capacity of dogs to communicate in a referential and intentional way with humans is considered a key outcome of how domestication as a companion animal shaped the canid brain. However, the lack of comparison with other domestic animals makes general conclusions about how domestication has affected these important cognitive features difficult. We investigated human-directed behaviour in an 'unsolvable problem' task in a domestic, but non-companion species: goats. During the test, goats experienced a forward-facing or an away-facing person. They gazed towards the forward-facing person earlier and for longer and showed more gaze alternations and a lower latency until the first gaze alternation when the person was forward-facing. Our results provide strong evidence for audience-dependent human-directed visual orienting behaviour in a species that was domesticated primarily for production, and show similarities with the referential and intentional communicative behaviour exhibited by domestic companion animals such as dogs and horses. This indicates that domestication has a much broader impact on heterospecific communication than previously believed. © 2016 The Author(s).

Can E. coli fly?

DEFF Research Database (Denmark)

Lindeberg, Yrja Lisa; Egedal, Karen; Hossain, Zenat Zebin

2018-01-01

, and the numbers of flies landing on the exposed rice were counted. Following exposure, the surface of the rice was microbiologically and molecularly analysed for the presence of E. coli and genes of diarrheagenic E. coli and Shigella strains. RESULTS: Rice was at greater risk (p ... with E. coli if flies landed on the rice than if no flies landed on the rice (odds ratio 5·4 (p ...-landings, the average CFU per fly-landing was > 0·6 x 103 CFU. Genes of diarrheagenic E. coli and Shigella species were detected in 39 of 60 (65%) of exposed rice samples. Two fly species were identified; the common housefly (Musca domestica) and the oriental latrine fly (Chrysomya megacephala). CONCLUSION: Flies may...

The effect of varying talker identity and listening conditions on gaze behavior during audiovisual speech perception.

Science.gov (United States)

Buchan, Julie N; Paré, Martin; Munhall, Kevin G

2008-11-25

During face-to-face conversation the face provides auditory and visual linguistic information, and also conveys information about the identity of the speaker. This study investigated behavioral strategies involved in gathering visual information while watching talking faces. The effects of varying talker identity and varying the intelligibility of speech (by adding acoustic noise) on gaze behavior were measured with an eyetracker. Varying the intelligibility of the speech by adding noise had a noticeable effect on the location and duration of fixations. When noise was present subjects adopted a vantage point that was more centralized on the face by reducing the frequency of the fixations on the eyes and mouth and lengthening the duration of their gaze fixations on the nose and mouth. Varying talker identity resulted in a more modest change in gaze behavior that was modulated by the intelligibility of the speech. Although subjects generally used similar strategies to extract visual information in both talker variability conditions, when noise was absent there were more fixations on the mouth when viewing a different talker every trial as opposed to the same talker every trial. These findings provide a useful baseline for studies examining gaze behavior during audiovisual speech perception and perception of dynamic faces.

Fly ash carbon passivation

Science.gov (United States)

La Count, Robert B; Baltrus, John P; Kern, Douglas G

2013-05-14

A thermal method to passivate the carbon and/or other components in fly ash significantly decreases adsorption. The passivated carbon remains in the fly ash. Heating the fly ash to about 500 and 800 degrees C. under inert gas conditions sharply decreases the amount of surfactant adsorbed by the fly ash recovered after thermal treatment despite the fact that the carbon content remains in the fly ash. Using oxygen and inert gas mixtures, the present invention shows that a thermal treatment to about 500 degrees C. also sharply decreases the surfactant adsorption of the recovered fly ash even though most of the carbon remains intact. Also, thermal treatment to about 800 degrees C. under these same oxidative conditions shows a sharp decrease in surfactant adsorption of the recovered fly ash due to the fact that the carbon has been removed. This experiment simulates the various "carbon burnout" methods and is not a claim in this method. The present invention provides a thermal method of deactivating high carbon fly ash toward adsorption of AEAs while retaining the fly ash carbon. The fly ash can be used, for example, as a partial Portland cement replacement in air-entrained concrete, in conductive and other concretes, and for other applications.

FliO Regulation of FliP in the Formation of the Salmonella enterica Flagellum

OpenAIRE

Barker, Clive S.; Meshcheryakova, Irina V.; Kostyukova, Alla S.; Samatey, Fadel A.

2010-01-01

The type III secretion system of the Salmonella flagellum consists of 6 integral membrane proteins: FlhA, FlhB, FliO, FliP, FliQ, and FliR. However, in some other type III secretion systems, a homologue of FliO is apparently absent, suggesting it has a specialized role. Deleting the fliO gene from the chromosome of a motile strain of Salmonella resulted in a drastic decrease of motility. Incubation of the ΔfliO mutant strain in motility agar, gave rise to pseudorevertants containing extrageni...

Gazing behavior during mixed-sex interactions: Sex and attractiveness effects

NARCIS (Netherlands)

Straaten, I. van; Holland, R.W.; Finkenauer, C.; Hollenstein, T.P.; Engels, R.C.M.E.

2010-01-01

We investigated to what extent the length of people's gazes during conversations with opposite-sex persons is affected by the physical attractiveness of the partner. Single participants (N = 115) conversed for 5 min with confederates who were rated either as low or high on physical attractiveness.

Towards emotion modeling based on gaze dynamics in generic interfaces

DEFF Research Database (Denmark)

Vester-Christensen, Martin; Leimberg, Denis; Ersbøll, Bjarne Kjær

2005-01-01

Gaze detection can be a useful ingredient in generic human computer interfaces if current technical barriers are overcome. We discuss the feasibility of concurrent posture and eye-tracking in the context of single (low cost) camera imagery. The ingredients in the approach are posture and eye region...

Neural Temporal Dynamics of Social Exclusion Elicited by Averted Gaze: An Event-Related Potentials Study

Directory of Open Access Journals (Sweden)

Yue Leng

2018-02-01

Full Text Available Eye gaze plays a fundamental role in social communication. The averted eye gaze during social interaction, as the most common form of silent treatment, conveys a signal of social exclusion. In the present study, we examined the time course of brain response to social exclusion by using a modified version of Eye-gaze paradigm. The event-related potentials (ERPs data and the subjective rating data showed that the frontocentral P200 was positively correlated with negative mood of excluded events, whereas, the centroparietal late positive potential (LPP was positively correlated with the perceived ostracism intensity. Both the P200 and LPP were more positive-going for excluded events than for included events. These findings suggest that brain responses sensitive to social exclusion can be divided into the early affective processing stage, linking to the early pre-cognitive warning system; and the late higher-order processes stage, demanding attentional resources for elaborate stimuli evaluation and categorization generally not under specific situation.

Mercury release from fly ashes and hydrated fly ash cement pastes

Science.gov (United States)

Du, Wen; Zhang, Chao-yang; Kong, Xiang-ming; Zhuo, Yu-qun; Zhu, Zhen-wu

2018-04-01

The large-scale usage of fly ash in cement and concrete introduces mercury (Hg) into concrete structures and a risk of secondary emission of Hg from the structures during long-term service was evaluated. Three fly ashes were collected from coal-fired power plants and three blend cements were prepared by mixing Ordinary Portland cement (OPC) with the same amount of fly ash. The releasing behaviors of Hg0 from the fly ash and the powdered hydrated cement pastes (HCP) were measured by a self-developed Hg measurement system, where an air-blowing part and Hg collection part were involved. The Hg release of fly ashes at room temperature varied from 25.84 to 39.69 ng/g fly ash during 90-days period of air-blowing experiment. In contrast, the Hg release of the HCPs were in a range of 8.51-18.48 ng/g HCP. It is found that the Hg release ratios of HCPs were almost the same as those of the pure fly ashes, suggesting that the hydration products of the HCP have little immobilization effect on Hg0. Increasing temperature and moisture content markedly promote the Hg release.

Design of a Binocular Pupil and Gaze Point Detection System Utilizing High Definition Images

Directory of Open Access Journals (Sweden)

Yilmaz Durna

2017-05-01

Full Text Available This study proposes a novel binocular pupil and gaze detection system utilizing a remote full high definition (full HD camera and employing LabVIEW. LabVIEW is inherently parallel and has fewer time-consuming algorithms. Many eye tracker applications are monocular and use low resolution cameras due to real-time image processing difficulties. We utilized the computer’s direct access memory channel for rapid data transmission and processed full HD images with LabVIEW. Full HD images make easier determinations of center coordinates/sizes of pupil and corneal reflection. We modified the camera so that the camera sensor passed only infrared (IR images. Glints were taken as reference points for region of interest (ROI area selection of the eye region in the face image. A morphologic filter was applied for erosion of noise, and a weighted average technique was used for center detection. To test system accuracy with 11 participants, we produced a visual stimulus set up to analyze each eye’s movement. Nonlinear mapping function was utilized for gaze estimation. Pupil size, pupil position, glint position and gaze point coordinates were obtained with free natural head movements in our system. This system also works at 2046 × 1086 resolution at 40 frames per second. It is assumed that 280 frames per second for 640 × 480 pixel images is the case. Experimental results show that the average gaze detection error for 11 participants was 0.76° for the left eye, 0.89° for right eye and 0.83° for the mean of two eyes.

Fly ash aggregates. Vliegaskunstgrind

Energy Technology Data Exchange (ETDEWEB)

1983-03-01

A study has been carried out into artificial aggregates made from fly ash, 'fly ash aggregates'. Attention has been drawn to the production of fly ash aggregates in the Netherlands as a way to obviate the need of disposal of fly ash. Typical process steps for the manufacturing of fly ash aggregates are the agglomeration and the bonding of fly ash particles. Agglomeration techniques are subdivided into agitation and compaction, bonding methods into sintering, hydrothermal and 'cold' bonding. In sintering no bonding agent is used. The fly ash particles are more or less welded together. Sintering in general is performed at a temperature higher than 900 deg C. In hydrothermal processes lime reacts with fly ash to a crystalline hydrate at temperatures between 100 and 250 deg C at saturated steam pressure. As a lime source not only lime as such, but also portland cement can be used. Cold bonding processes rely on reaction of fly ash with lime or cement at temperatures between 0 and 100 deg C. The pozzolanic properties of fly ash are used. Where cement is applied, this bonding agent itself contributes also to the strength development of the artificial aggregate. Besides the use of lime and cement, several processes are known which make use of lime containing wastes such as spray dry absorption desulfurization residues or fluid bed coal combustion residues. (In Dutch)

Hydration of fly ash cement and microstructure of fly ash cement pastes

Energy Technology Data Exchange (ETDEWEB)

Shiyuan, H.

1981-01-01

The strength development and hydration of fly ash cement and the influence of addition of gypsum on those were studied at normal and elevated temperatures. It was found that an addition of a proper amount of gypsum to fly ash cement could accelerate the pozzolanic reaction between CH and fly ash, and as a result, increase the strength of fly ash cement pastes after 28 days.

Watt steam governor stability

Science.gov (United States)

Denny, Mark

2002-05-01

The physics of the fly-ball governor, introduced to regulate the speed of steam engines, is here analysed anew. The original analysis is generalized to arbitrary governor geometry. The well-known stability criterion for the linearized system breaks down for large excursions from equilibrium; we show approximately how this criterion changes.

Eye Pull, Eye Push: Moving Objects between Large Screens and Personal Devices with Gaze and Touch

OpenAIRE

Turner , Jayson; Alexander , Jason; Bulling , Andreas; Schmidt , Dominik; Gellersen , Hans

2013-01-01

Part 4: Gaze-Enabled Interaction Design; International audience; Previous work has validated the eyes and mobile input as a viable approach for pointing at, and selecting out of reach objects. This work presents Eye Pull, Eye Push, a novel interaction concept for content transfer between public and personal devices using gaze and touch. We present three techniques that enable this interaction: Eye Cut & Paste, Eye Drag & Drop, and Eye Summon & Cast. We outline and discuss several scenarios in...

Neurocognitive mechanisms of gaze-expression interactions in face processing and social attention.

Science.gov (United States)

Graham, Reiko; Labar, Kevin S

2012-04-01

The face conveys a rich source of non-verbal information used during social communication. While research has revealed how specific facial channels such as emotional expression are processed, little is known about the prioritization and integration of multiple cues in the face during dyadic exchanges. Classic models of face perception have emphasized the segregation of dynamic vs. static facial features along independent information processing pathways. Here we review recent behavioral and neuroscientific evidence suggesting that within the dynamic stream, concurrent changes in eye gaze and emotional expression can yield early independent effects on face judgments and covert shifts of visuospatial attention. These effects are partially segregated within initial visual afferent processing volleys, but are subsequently integrated in limbic regions such as the amygdala or via reentrant visual processing volleys. This spatiotemporal pattern may help to resolve otherwise perplexing discrepancies across behavioral studies of emotional influences on gaze-directed attentional cueing. Theoretical explanations of gaze-expression interactions are discussed, with special consideration of speed-of-processing (discriminability) and contextual (ambiguity) accounts. Future research in this area promises to reveal the mental chronometry of face processing and interpersonal attention, with implications for understanding how social referencing develops in infancy and is impaired in autism and other disorders of social cognition. Copyright © 2012 Elsevier Ltd. All rights reserved.

The response of guide dogs and pet dogs (Canis familiaris) to cues of human referential communication (pointing and gaze).

Science.gov (United States)

Ittyerah, Miriam; Gaunet, Florence

2009-03-01

The study raises the question of whether guide dogs and pet dogs are expected to differ in response to cues of referential communication given by their owners; especially since guide dogs grow up among sighted humans, and while living with their blind owners, they still have interactions with several sighted people. Guide dogs and pet dogs were required to respond to point, point and gaze, gaze and control cues of referential communication given by their owners. Results indicate that the two groups of dogs do not differ from each other, revealing that the visual status of the owner is not a factor in the use of cues of referential communication. Both groups of dogs have higher frequencies of performance and faster latencies for the point and the point and gaze cues as compared to gaze cue only. However, responses to control cues are below chance performance for the guide dogs, whereas the pet dogs perform at chance. The below chance performance of the guide dogs may be explained by a tendency among them to go and stand by the owner. The study indicates that both groups of dogs respond similarly in normal daily dyadic interaction with their owners and the lower comprehension of the human gaze may be a less salient cue among dogs in comparison to the pointing gesture.

Experimental study on the solidification and influence factors of MSW stabilized soil

Directory of Open Access Journals (Sweden)

Wang Zhiping

2015-01-01

Full Text Available The effect of kinds and dosage of curing agent on the curing effect and strength characteristics of municipal solid waste (MSW stabilized soil is very obvious. In order to reveal these effects, this paper uses cement, fly ash, lime and gypsum as main curing agent and additives to make MSW stabilized soil samples of different components and contents and its strength is obtained using unconfined compressive strength test. The results showed that the curing age, dosage of cement, fly ash, lime and gypsum have effect on the strengths of stabilized MSW soil. The bigger the content of cement and fly ash, the higher the strength of stabilized soil. But the amount of lime and gypsum has a critical value. Within the critical value, the strength of the stabilized soil increases with the increasing of the content of the additives, and decreases with the increase of the additives content if the content of the additives exceeds the critical value. The curing age has much effect on the strength of the stabilized soil. The strength of the samples for 7 days is far less than that for 28 days. This can be explained that: when the curing agent is added into the stabilized soil, the connection among the particles of the MSW soil is changed from weak connection to bond connection, and therefore the strength of the curing MSW soil is improved.

Ommatidia of blow fly, house fly, and flesh fly: implication of their vision efficiency.

Science.gov (United States)

Sukontason, Kabkaew L; Chaiwong, Tarinee; Piangjai, Somsak; Upakut, Sorawit; Moophayak, Kittikhun; Sukontason, Kom

2008-06-01

This work aims to elucidate the number of ommatidia or facets (the outwardly visible units of each ommatidium) for compound eyes in blow flies [Chrysomya megacephala (F.), Chrysomya rufifacies (Macquart), Chrysomya nigripes (Aubertin), Lucilia cuprina (Wiedemann)], house flies (Musca domestica L.), and flesh flies (Liosarcophaga dux Thomson) by manual counts of the corneal spreads. The head of the fly in each species was soaked in 20% potassium hydroxide solution at room temperature for 7 days, and the clear compound eye was dissected into six small parts, each of which was placed onto a slide and flattened using a coverslip. Images of each part were obtained using a microscope connected to a computer. The printed images of each part were magnified, and the total number of ommatidia per eye was manually counted. For males, the mean number of ommatidia was statistically different among all flies examined: L. dux (6,032) > C. rufifacies (5,356) > C. nigripes (4,798) > C. megacephala (4,376) > L. cuprina (3,665) > M. domestica (3,484). Likewise, the mean number of facets in females was statistically different: L. dux (6,086) > C. megacephala (5,641) > C. rufifacies (5,208) > C. nigripes (4,774) > L. cuprina (3,608) > M. domestica (3433). Scanning electron microscopy analysis of adult flies revealed the sexual dimorphism in the compound eye. Male C. megacephala had large ommatidia in the upper two thirds part and small ommatidia in the lower one third part, whereas only small ommatidia were detected in females. Dense postulate appearance was detected in the external surface of the corneal lens of the ommatidia of C. megacephala, C. rufifacies, and C. nigripes, while a mix of dense postulate appearance and variable groove array length was detected in L. cuprina and M. domestica. The probable functions of ommatidia are discussed with reference to other literature.

Fly ash stabilisation of gravel roads; Flygaska som foerstaerkningslager i grusvaeg

Energy Technology Data Exchange (ETDEWEB)

Macsik, Josef

2006-01-15

transported trough the road section stabilised at Norberg, without any stability problems. The stabilisation effect can be destroyed by the effect of water and frost, and results indicate that road ditches and are of great importance. After thawing the stabilised roads bearing capacity is decreased after the first year. Leaching and transport of heavy metals from the road construction is in the same level as from the reference section. However, leaching of Na, K and sulphate are increased. This report shows that fly ash stabilisation gives an increase of bearing capacity of gravel roads. Water in the road construction leads to an increase of leaching, a reduction in bearing capacity and decreased frost resistance. Drainage of fly ash stabilised roads are essential due to bearing capacity and environment. Fly ash production is limited and use of fly ash stabilised gravel is more efficient as less fly ash is required than when only fly ash is used.

Illusory shadow person causing paradoxical gaze deviations during temporal lobe seizures

NARCIS (Netherlands)

Zijlmans, M.; van Eijsden, P.; Ferrier, C. H.; Kho, K. H.; van Rijen, P. C.; Leijten, F. S. S.

Generally, activation of the frontal eye field during seizures can cause versive (forced) gaze deviation, while non-versive head deviation is hypothesised to result from ictal neglect after inactivation of the ipsilateral temporoparietal area. Almost all non-versive head deviations occurring during

Intentional gaze shift to neglected space: a compensatory strategy during recovery after unilateral spatial neglect.

Science.gov (United States)

Takamura, Yusaku; Imanishi, Maho; Osaka, Madoka; Ohmatsu, Satoko; Tominaga, Takanori; Yamanaka, Kentaro; Morioka, Shu; Kawashima, Noritaka

2016-11-01

Unilateral spatial neglect is a common neurological syndrome following predominantly right hemispheric stroke. While most patients lack insight into their neglect behaviour and do not initiate compensatory behaviours in the early recovery phase, some patients recognize it and start to pay attention towards the neglected space. We aimed to characterize visual attention capacity in patients with unilateral spatial neglect with specific focus on cortical processes underlying compensatory gaze shift towards the neglected space during the recovery process. Based on the Behavioural Inattention Test score and presence or absence of experience of neglect in their daily life from stroke onset to the enrolment date, participants were divided into USN+‰‰+ (do not compensate, n = 15), USN+ (compensate, n = 10), and right hemisphere damage groups (no neglect, n = 24). The patients participated in eye pursuit-based choice reaction tasks and were asked to pursue one of five horizontally located circular objects flashed on a computer display. The task consisted of 25 trials with 4-s intervals, and the order of highlighted objects was randomly determined. From the recorded eye tracking data, eye movement onset and gaze shift were calculated. To elucidate the cortical mechanism underlying behavioural results, electroencephalagram activities were recorded in three USN+‰‰+, 13 USN+ and eight patients with right hemisphere damage. We found that while lower Behavioural Inattention Test scoring patients (USN+‰‰+) showed gaze shift to non-neglected space, some higher scoring patients (USN+) showed clear leftward gaze shift at visual stimuli onset. Moreover, we found a significant correlation between Behavioural Inattention Test score and gaze shift extent in the unilateral spatial neglect group (r = -0.62, P attention to the neglected space) and its neural correlates in patients with unilateral spatial neglect. In conclusion, patients with unilateral spatial neglect who recognized

Field and lab evaluation of the use of lime fly ash to replace soil cement as a base course : final report.

Science.gov (United States)

1997-09-01

This study evaluates the performance of lime/fly ash stabilized base as an alternative to soil cement stabilized base for flexible pavement systems on reconstructed highways in Louisiana. Louisiana has historically used soil cement for most flexible ...

The Role of Clay Swelling and Mineral Neoformation in the Stabilization of High Plasticity Soils Treated with the Fly Ash- and Metakaolin-Based Geopolymers

Directory of Open Access Journals (Sweden)

Mahmoud A. Mahrous

2018-04-01

Full Text Available In the southern U.S. states, expansive soils are frequently encountered, presenting an important hazard in geotechnical engineering. This research relies on mineralogical and geochemical clues to explain the swelling behavior of smectite-rich, high-plasticity soils, documented in a series of geomechanical swelling tests that were performed on the soils stabilized with the metakaolin (MKG and fly ash (FAG based geopolymers. These geopolymers were mixed with the soil at several concentration levels. The lowest swelling percentage was shown to correspond to the sample stabilized with 12% FAG and was attributed to the neoformation of calcium silicate hydrates that acted as a cementitious material, preventing the soil from expanding by occupying the pore space, thus binding the clay particles together. Conversely, the 12% MKG-stabilized soil exhibited enormous expansion, which was explained by montmorillonite swelling to the point that it gradually began to lose its structural periodicity. The relatively high abundance of the newly formed feldspathoids in MKG-treated samples is believed to have greatly contributed to the overall soil expansion. Finally, the cation exchange capacity tests showed that the percentage of Na+ and Ca2+, as well as the pH value, exercised strong control on the swelling behavior of smectitic soils.

Comparison of various physiological traits in flies (Drosophila melanogaster) of wild origin, infected or uninfected by the hereditary Rhabdovirus sigma.

Science.gov (United States)

Fleuriet, A

1981-01-01

Flies infected or uninfected by the hereditary Rhabdovirus sigma have been collected in the natural French populations of Drosophila melanogaster. The have been compared for various physiological traits: male and female fertility, female longevity, sexual selection and egg viability. The only significant difference was the lower viability of eggs laid by infected females. For all the other traits, infected and uninfected flies were quite comparable. The viral types found in flies of wild origin, thus appear to be almost harmless for their carriers. This result can be connected with previous findings which gave evidence for the relative infrequency of infectious particles in stabilized flies of wild origin.

The Fly Printer - Extended

DEFF Research Database (Denmark)

Beloff, Laura; Klaus, Malena

2016-01-01

Artist talk / Work-in-progress What is the purpose of a machine or an artifact, like the Fly Printer, that is dislocated, that produces images that have no meaning, no instrumentality, that depict nothing in the world? The biological and the cultural are reunited in this apparatus as a possibility...... to break through a common way of depicting the world, trying to find different surfaces and using strange apparatus to insist in the interstice of visibility. The Fly Printer is a printing apparatus in a form of a closed environment that contains a flock of fruit flies. The flies eat special food...... that is prepared for them that is mixed with laser jet printer inks. The flies digest the food and gradually print different color dots onto the paper that is placed under the fly habitat. In the Fly Printer biological organisms are used for replacing a standard part of our common printer technology. The work...

Exploration of Computer Game Interventions in Improving Gaze Following Behavior in Children with Autism Spectrum Disorders

OpenAIRE

Kane, Jessi Lynn

2011-01-01

Statistics show the prevalence of autism spectrum disorder (ASD), a developmental delay disorder, is now 1 in 110 children in the United States (Rice, 2009), nearing 1% of the population. Therefore, this study looked at ways modern technology could assist these children and their families. One deficit in ASD is the inability to respond to gaze referencing (i.e. follow the eye gaze of another adult/child/etc), a correlate of the responding to joint attention (RJA) process. This not only aff...

Is improved lane keeping during cognitive load caused by increased physical arousal or gaze concentration toward the road center?

Science.gov (United States)

Li, Penghui; Markkula, Gustav; Li, Yibing; Merat, Natasha

2018-08-01

Driver distraction is one of the main causes of motor-vehicle accidents. However, the impact on traffic safety of tasks that impose cognitive (non-visual) distraction remains debated. One particularly intriguing finding is that cognitive load seems to improve lane keeping performance, most often quantified as reduced standard deviation of lateral position (SDLP). The main competing hypotheses, supported by current empirical evidence, suggest that cognitive load improves lane keeping via either increased physical arousal, or higher gaze concentration toward the road center, but views are mixed regarding if, and how, these possible mediators influence lane keeping performance. Hence, a simulator study was conducted, with participants driving on a straight city road section whilst completing a cognitive task at different levels of difficulty. In line with previous studies, cognitive load led to increased physical arousal, higher gaze concentration toward the road center, and higher levels of micro-steering activity, accompanied by improved lane keeping performance. More importantly, during the high cognitive task, both physical arousal and gaze concentration changed earlier in time than micro-steering activity, which in turn changed earlier than lane keeping performance. In addition, our results did not show a significant correlation between gaze concentration and physical arousal on the level of individual task recordings. Based on these findings, various multilevel models for micro-steering activity and lane keeping performance were conducted and compared, and the results suggest that all of the mechanisms proposed by existing hypotheses could be simultaneously involved. In other words, it is suggested that cognitive load leads to: (i) an increase in arousal, causing increased micro-steering activity, which in turn improves lane keeping performance, and (ii) an increase in gaze concentration, causing lane keeping improvement through both (a) further increased micro

Maori in the Kingdom of the Gaze: Subjects or Critics?

Science.gov (United States)

Mika, Carl; Stewart, Georgina

2016-01-01

For Maori, a real opportunity exists to flesh out some terms and concepts that Western thinkers have adopted and that precede disciplines but necessarily inform them. In this article, we are intent on describing one of these precursory phenomena--Foucault's Gaze--within a framework that accords with a Maori philosophical framework. Our discussion…

Automatic and strategic measures as predictors of mirror gazing among individuals with body dysmorphic disorder symptoms.

Science.gov (United States)

Clerkin, Elise M; Teachman, Bethany A

2009-08-01

The current study tests cognitive-behavioral models of body dysmorphic disorder (BDD) by examining the relationship between cognitive biases and correlates of mirror gazing. To provide a more comprehensive picture, we investigated both relatively strategic (i.e., available for conscious introspection) and automatic (i.e., outside conscious control) measures of cognitive biases in a sample with either high (n = 32) or low (n = 31) BDD symptoms. Specifically, we examined the extent that (1) explicit interpretations tied to appearance, as well as (2) automatic associations and (3) strategic evaluations of the importance of attractiveness predict anxiety and avoidance associated with mirror gazing. Results indicated that interpretations tied to appearance uniquely predicted self-reported desire to avoid, whereas strategic evaluations of appearance uniquely predicted peak anxiety associated with mirror gazing, and automatic appearance associations uniquely predicted behavioral avoidance. These results offer considerable support for cognitive models of BDD, and suggest a dissociation between automatic and strategic measures.

Automatic and Strategic Measures as Predictors of Mirror Gazing Among Individuals with Body Dysmorphic Disorder Symptoms

Science.gov (United States)

Clerkin, Elise M.; Teachman, Bethany A.

2011-01-01

The current study tests cognitive-behavioral models of body dysmorphic disorder (BDD) by examining the relationship between cognitive biases and correlates of mirror gazing. To provide a more comprehensive picture, we investigated both relatively strategic (i.e., available for conscious introspection) and automatic (i.e., outside conscious control) measures of cognitive biases in a sample with either high (n=32) or low (n=31) BDD symptoms. Specifically, we examined the extent that 1) explicit interpretations tied to appearance, as well as 2) automatic associations and 3) strategic evaluations of the importance of attractiveness predict anxiety and avoidance associated with mirror gazing. Results indicated that interpretations tied to appearance uniquely predicted self-reported desire to avoid, while strategic evaluations of appearance uniquely predicted peak anxiety associated with mirror gazing, and automatic appearance associations uniquely predicted behavioral avoidance. These results offer considerable support for cognitive models of BDD, and suggest a dissociation between automatic and strategic measures. PMID:19684496

Children's Bricolage under the Gaze of Teachers in Sociodramatic Play

Science.gov (United States)

Tam, Po Chi

2013-01-01

Drawing on the theory of dialogism and the literature on children's culture and cultural resistance, this article investigates the contextual and textual features of the cultural making of a group of children in sociodramatic play in a Hong Kong kindergarten. Different from other, similar studies, this study reports that under the gaze of the…

Accuracy of Outcome Anticipation, But Not Gaze Behavior, Differs Against Left- and Right-Handed Penalties in Team-Handball Goalkeeping.

Science.gov (United States)

Loffing, Florian; Sölter, Florian; Hagemann, Norbert; Strauss, Bernd

2015-01-01

Low perceptual familiarity with relatively rarer left-handed as opposed to more common right-handed individuals may result in athletes' poorer ability to anticipate the former's action intentions. Part of such left-right asymmetry in visual anticipation could be due to an inefficient gaze strategy during confrontation with left-handed individuals. To exemplify, observers may not mirror their gaze when viewing left- vs. right-handed actions but preferentially fixate on an opponent's right body side, irrespective of an opponent's handedness, owing to the predominant exposure to right-handed actions. So far empirical verification of such assumption, however, is lacking. Here we report on an experiment where team-handball goalkeepers' and non-goalkeepers' gaze behavior was recorded while they predicted throw direction of left- and right-handed 7-m penalties shown as videos on a computer monitor. As expected, goalkeepers were considerably more accurate than non-goalkeepers and prediction was better against right- than left-handed penalties. However, there was no indication of differences in gaze measures (i.e., number of fixations, overall and final fixation duration, time-course of horizontal or vertical fixation deviation) as a function of skill group or the penalty-takers' handedness. Findings suggest that inferior anticipation of left-handed compared to right-handed individuals' action intentions may not be associated with misalignment in gaze behavior. Rather, albeit looking similarly, accuracy differences could be due to observers' differential ability of picking up and interpreting the visual information provided by left- vs. right-handed movements.

The onion fly

International Nuclear Information System (INIS)

Loosjes, M.

1990-01-01

This paper describes the origin, practical application, problems in application and prospects of control of the onion fly, Delia antiqua (Diptera: Anthomyiidae), in the Netherlands by the Sterile Insect Technique (SIT). The larva of the onion fly is a severe pest in onions in temperate regions. Development of resistance of the onion fly against insecticides caused research on the SIT to be started by the Dutch Government in 1965. This research was on mass-rearing, long-term storage of pupae, sterilization, and release and ratio assessment techniques. By 1979 sufficient information had been turned over to any interested private company. In the case of the onion fly the SIT can be applied like a control treatment instead of chemical control to individual onion fields. This is due to the limited dispersal activity of the flies and the scattered distribution of onion fields in the Netherlands, with 5-10% of the onion growing areas planted with onions

Soluble components of the flagellar export apparatus, FliI, FliJ, and FliH, do not deliver flagellin, the major filament protein, from the cytosol to the export gate.

Science.gov (United States)

Sajó, Ráchel; Liliom, Károly; Muskotál, Adél; Klein, Agnes; Závodszky, Péter; Vonderviszt, Ferenc; Dobó, József

2014-11-01

Flagella, the locomotion organelles of bacteria, extend from the cytoplasm to the cell exterior. External flagellar proteins are synthesized in the cytoplasm and exported by the flagellar type III secretion system. Soluble components of the flagellar export apparatus, FliI, FliH, and FliJ, have been implicated to carry late export substrates in complex with their cognate chaperones from the cytoplasm to the export gate. The importance of the soluble components in the delivery of the three minor late substrates FlgK, FlgL (hook-filament junction) and FliD (filament-cap) has been convincingly demonstrated, but their role in the transport of the major filament component flagellin (FliC) is still unclear. We have used continuous ATPase activity measurements and quartz crystal microbalance (QCM) studies to characterize interactions between the soluble export components and flagellin or the FliC:FliS substrate-chaperone complex. As controls, interactions between soluble export component pairs were characterized providing Kd values. FliC or FliC:FliS did not influence the ATPase activity of FliI alone or in complex with FliH and/or FliJ suggesting lack of interaction in solution. Immobilized FliI, FliH, or FliJ did not interact with FliC or FliC:FliS detected by QCM. The lack of interaction in the fluid phase between FliC or FliC:FliS and the soluble export components, in particular with the ATPase FliI, suggests that cells use different mechanisms for the export of late minor substrates, and the major substrate, FliC. It seems that the abundantly produced flagellin does not require the assistance of the soluble export components to efficiently reach the export gate. Copyright © 2014 Elsevier B.V. All rights reserved.

Field and lab evaluation of the use of lime fly ash to replace soil cement as a base course : technical summary.

Science.gov (United States)

1997-09-01

The purpose of this project was to design and construct lime/fly ash stabilized base course test sections which would be economical compared to a soil cement stabilized base, utilize a recyclable material, and possibly reduce shrinkage cracking on ba...

Interaction of feel system and flight control system dynamics on lateral flying qualities

Science.gov (United States)

Bailey, R. E.; Knotts, L. H.

1990-01-01

An experimental investigation of the influence of lateral feel system characteristics on fighter aircraft roll flying qualities was conducted using the variable stability USAF NT-33. Forty-two evaluation flights were flown by three engineering test pilots. The investigation utilized the power approach, visual landing task and up-and-away tasks including formation, gun tracking, and computer-generated compensatory attitude tracking tasks displayed on the Head-Up Display. Experimental variations included the feel system frequency, force-deflection gradient, control system command type (force or position input command), aircraft roll mode time constant, control system prefilter frequency, and control system time delay. The primary data were task performance records and evaluation pilot comments and ratings using the Cooper-Harper scale. The data highlight the unique and powerful effect of the feel system of flying qualities. The data show that the feel system is not 'equivalent' in flying qualities influence to analogous control system elements. A lower limit of allowable feel system frequency appears warranted to ensure good lateral flying qualities. Flying qualities criteria should most properly treat the feel system dynamic influence separately from the control system, since the input and output of this dynamic element is apparent to the pilot and thus, does not produce a 'hidden' effect.

Stabilized fiber-reinforced pavement base course with recycled aggregate

Science.gov (United States)

Sobhan, Khaled

This study evaluates the benefits to be gained by using a composite highway base course material consisting of recycled crushed concrete aggregate, portland cement, fly ash, and a modest amount of reinforcing fibers. The primary objectives of this research were to (a) quantify the improvement that is obtained by adding fibers to a lean concrete composite (made from recycled aggregate and low quantities of Portland cement and/or fly ash), (b) evaluate the mechanical behavior of such a composite base course material under both static and repeated loads, and (c) utilize the laboratory-determined properties with a mechanistic design method to assess the potential advantages. The split tensile strength of a stabilized recycled aggregate base course material was found to be exponentially related to the compacted dry density of the mix. A lean mix containing 4% cement and 4% fly ash (by weight) develops sufficient unconfined compressive, split tensile, and flexural strengths to be used as a high quality stabilized base course. The addition of 4% (by weight) of hooked-end steel fibers significantly enhances the post-peak load-deformation response of the composite in both indirect tension and static flexure. The flexural fatigue behavior of the 4% cement-4% fly ash mix is comparable to all commonly used stabilized materials, including regular concrete; the inclusion of 4% hooked-end fibers to this mix significantly improves its resistance to fatigue failure. The resilient moduli of stabilized recycled aggregate in flexure are comparable to the values obtained for traditional soil-cement mixes. In general, the fibers are effective in retarding the rate of fatigue damage accumulation, which is quantified in terms of a damage index defined by an energy-based approach. The thickness design curves for a stabilized recycled aggregate base course, as developed by using an elastic layer approach, is shown to be in close agreement with a theoretical model (based on Westergaard

A 2D eye gaze estimation system with low-resolution webcam images

Directory of Open Access Journals (Sweden)

Kim Jin

2011-01-01

Full Text Available Abstract In this article, a low-cost system for 2D eye gaze estimation with low-resolution webcam images is presented. Two algorithms are proposed for this purpose, one for the eye-ball detection with stable approximate pupil-center and the other one for the eye movements' direction detection. Eyeball is detected using deformable angular integral search by minimum intensity (DAISMI algorithm. Deformable template-based 2D gaze estimation (DTBGE algorithm is employed as a noise filter for deciding the stable movement decisions. While DTBGE employs binary images, DAISMI employs gray-scale images. Right and left eye estimates are evaluated separately. DAISMI finds the stable approximate pupil-center location by calculating the mass-center of eyeball border vertices to be employed for initial deformable template alignment. DTBGE starts running with initial alignment and updates the template alignment with resulting eye movements and eyeball size frame by frame. The horizontal and vertical deviation of eye movements through eyeball size is considered as if it is directly proportional with the deviation of cursor movements in a certain screen size and resolution. The core advantage of the system is that it does not employ the real pupil-center as a reference point for gaze estimation which is more reliable against corneal reflection. Visual angle accuracy is used for the evaluation and benchmarking of the system. Effectiveness of the proposed system is presented and experimental results are shown.

Examining Vision and Attention in Sports Performance Using a Gaze-Contingent Paradigm

Directory of Open Access Journals (Sweden)

Donghyun Ryu

2012-10-01

Full Text Available In time-constrained activities, such as competitive sports, the rapid acquisition and comprehension of visual information is vital for successful performance. Currently our understanding of how and what visual information is acquired and how this changes with skill development is quite rudimentary. Interpretation of eye movement behaviour is limited by uncertainties surrounding the relationship between attention, line-of-gaze data, and the mechanism of information pick-up from different sectors of the visual field. We used gaze-contingent display methodology to provide a selective information presentation to the central and peripheral parts of the visual field while performing a decision-making task. Eleven skilled and 11 less-skilled players watched videos of basketball scenarios under three different vision conditions (tunnel, masked, and full vision and in a forced-choice paradigm responded whether it was more appropriate for the ball carrier to pass or drive. In the tunnel and mask conditions vision was selectively restricted to, or occluded from, 5o around the line of gaze respectively. The skilled players showed significantly higher response accuracy and faster response times compared to their lesser skilled counterparts irrespective of the vision condition, demonstrating the skilled players' superiority in information extraction irrespective of the segment of visual field they rely on. Findings suggest that the capability to interpret visual information appears to be the key limiting factor to expert performance rather than the sector of the visual field in which the information is detected.

LAND WHERE YOU LOOK? – FUNCTIONAL RELATIONSHIPS BETWEEN GAZE AND MOVEMENT BEHAVIOUR IN A BACKWARD SALTO

Directory of Open Access Journals (Sweden)

Thomas Heinen

2012-07-01

Full Text Available In most everyday actions the eyes look towards objects and locations they are engaged with in a specific task and this information is used to guide the corresponding action. The question is, however, whether this strategy also holds for skills incorporating a whole-body rotation in sport. Therefore, the goal of this study was to investigate relationships between gaze behaviour and movement behaviour in a complex gymnastics skill, namely the backward salto performed as a dismount on the uneven bars. Thirteen expert gymnasts were instructed to fixate a light spot on the landing mat during the downswing phase when performing a backward salto as dismount. The location of the light spot was varied systematically with regard to each gymnast’s individual landing distance. Time-discrete kinematic parameters of the swing motion and the dismount were measured. It was expected that fixating the gaze towards different locations of the light spot on the landing mat would directly affect the landing location. We had, however, no specific predictions on the effects of manipulating gaze direction on the remaining kinematic parameters. The hip angle at the top of the backswing, the duration of the downswing phase, the hip angle prior to kick-through, and the landing distance varied clearly as a function of the location of the light spot. It is concluded that fixating the gaze towards the landing mat serves the function to execute the skill in a way to land on a particular location.

Leachability of Heavy Metals from Lightweight Aggregates Made with Sewage Sludge and Municipal Solid Waste Incineration Fly Ash

Science.gov (United States)

Wei, Na

2015-01-01

Lightweight aggregate (LWA) production with sewage sludge and municipal solid waste incineration (MSWI) fly ash is an effective approach for waste disposal. This study investigated the stability of heavy metals in LWA made from sewage sludge and MSWI fly ash. Leaching tests were conducted to find out the effects of MSWI fly ash/sewage sludge (MSWI FA/SS) ratio, sintering temperature and sintering time. It was found that with the increase of MSWI FA/SS ratio, leaching rates of all heavy metals firstly decreased and then increased, indicating the optimal ratio of MSWI fly ash/sewage sludge was 2:8. With the increase of sintering temperature and sintering time, the heavy metal solidifying efficiencies were strongly enhanced by crystallization and chemical incorporations within the aluminosilicate or silicate frameworks during the sintering process. However, taking cost-savings and lower energy consumption into account, 1100 °C and 8 min were selected as the optimal parameters for LWA sample- containing sludge production. Furthermore, heavy metal leaching concentrations under these optimal LWA production parameters were found to be in the range of China’s regulatory requirements. It is concluded that heavy metals can be properly stabilized in LWA samples containing sludge and cannot be easily released into the environment again to cause secondary pollution. PMID:25961800

Temperature Effects on Olive Fruit Fly Infestation in the FlySim Cellular Automata Model

Science.gov (United States)

Bruno, Vincenzo; Baldacchini, Valerio; di Gregorio, Salvatore

FlySim is a Cellular Automata model developed for simulating infestation of olive fruit flies (Bactrocera Oleae) on olive (Olea europaea) groves. The flies move into the groves looking for mature olives where eggs are spawn. This serious agricultural problem is mainly tackled by using chemical agents at the first signs of the infestation, but organic productions with no or few chemicals are strongly requested by the market. Oil made with infested olives is poor in quality, nor olives are suitable for selling in stores. The FlySim model simulates the diffusion of flies looking for mature olives and the growing of flies due to atmospheric conditions. Foreseeing an infestation is the best way to prevent it and to reduce the need of chemicals in agriculture. In this work we investigated the effects of temperature on olive fruit flies and resulting infestation during late spring and summer.

Sexualized Branded Entertainment and the Male Consumer Gaze

Directory of Open Access Journals (Sweden)

Matthew P. McAllister

2014-03-01

Full Text Available This article applies the “male consumer gaze” – integrating work influenced by Erving Goffman and Laura Mulvey – to two branded televised events: the 2011 Victoria’s Secret Fashion Show and the 2012 Hooters International Swimsuit Pageant. Critiqued elements include gendered body positioning, televisual and narrativizing techniques, social and integrated media, and branding strategies that combine to create a flow of consumption-based male gazing. Such trends may intensify with changes in media economics and niche marketing.

Quality assurance project plan for the Chestnut Ridge Fly Ash Pond Stabilization Project at the Oak Ridge Y-12 Plant, Oak Ridge, Tennessee

International Nuclear Information System (INIS)

1996-07-01

The Chestnut Ridge Fly Ash Pond Stabilization (CRFAPS) Project will stabilize a 19-m-high (62-ft-high) earthen embankment across Upper McCoy Branch situated along the southern slope of Chestnut Ridge. This task will be accomplished by raising the crest of the embankment, reinforcing the face of the embankment, removing trees from the face and top of the embankment, and repairing the emergency spillway. The primary responsibilities of the team members are: Lockheed Martin Energy Systems, Inc., (Energy Systems) will be responsible for project integration, technical support, Title 3 field support, environmental oversight, and quality assurance (QA) oversight of the project; Foster Wheeler Environmental Corporation (FWENC) will be responsible for design and home office Title 3 support; MK-Ferguson of Oak Ridge Company (MK-F) will be responsible for health and safety, construction, and procurement of construction materials. Each of the team members has a QA program approved by the US Department of Energy (DOE) Oak Ridge Operations. This project-specific QA project plan (QAPP), which is applicable to all project activities, identifies and integrates the specific QA requirements from the participant's QA programs that are necessary for this project

Gaze Awareness in Agent-Based Early-Childhood Learning Application

OpenAIRE

Akkil , Deepak; Dey , Prasenjit; Salian , Deepshika; Rajput , Nitendra

2017-01-01

Part 6: Interaction with Children; International audience; Use of technological devices for early childhood learning is increasing. Now, kindergarten and primary school children use interactive applications on mobile phones and tablet computers to support and complement classroom learning. With increase in cognitive technologies, there is further potential to make such applications more engaging by understanding the user context. In this paper, we present the Little Bear, a gaze aware pedagog...

Gravel road stabilisation of Ehnsjoevaegen, Hallstavik[Using fly ash]; Skogsbilvaegsrenovering av Ehnsjoevaegen, Hallstavik

Energy Technology Data Exchange (ETDEWEB)

Macsik, Josef; Svedberg, Bo [Ecoloop, Stockholm (Sweden)

2006-03-15

under controlled conditions with optimal water content. Tipping from a gravel truck can optimise production speed further more. The results show that fly ash stabilised gravel gives a better road stability. Although fly ash contributes to leaching of e.g. Na and S, the heavy metal contents of the ground water in the vicinity of the road is lower after stabilisation.