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Total results: 642

Investigating the extent realistic moulage impacts on immersion and performance among undergraduate paramedicine students in a simulation-based trauma …

Year: 2018

Authors: BW Mills,AK Miles, T Phan, PMC Dykstra

Introduction: Many healthcare education commentators suggest that moulage can be used in simulation to enhance scenario realism. However, few studies investigate to what extent using moulage in simulation impacts learners. We undertook a mixed-methods pilot study investigating how moulage influences student immersion and performance in simulation. Methods: Fifty undergraduate paramedicine students were randomized into two groups completing a trauma-based scenario with or without patient moulage. Task immersion was determined via a self-report questionnaire (National Aeronautics and Space Administration Task Load Index), eye-tracking, and postsimulation interviews. Performance was measured via independent observation of video by two paramedic clinical educators and time-to-action—when students first applied pressure to the primary wound. Results: Eye-tracking suggested that students attended to the thigh wound more often with the inclusion of moulage than without. National Aeronautics and Space Administration Task Load Index data suggested that the inclusion of moulage heightened students' feeling of being rushed throughout the scenario. This elicited an expedited performance of tasks with moulage present compared with not. Students experienced greater immersion with the inclusion of moulage. However, including moulage enhanced scenario difficulty to the extent that overall clinical performance was negatively affected. However, no differences were found when more heavily weighting items felt to contribute most to the survivability of the patient. Conclusions: Including moulage engendered immersion and a greater sense of urgency and did not sacrifice performance of key life-saving interventions. As a result of undertaking this pilot project, we suggest that a large-scale randomized controlled trial is feasible and should be undertaken before implementing change to curricula.

5 versions available

Looking for Holograms? Viewing Behaviour in Viewport-limited Augmented Reality

Year: 2018

Authors: N Kaulitz

Augmented reality allows perception of and interaction with virtual objects in the real world. Especially with head mounted displays, with which a user sees the world through a glasses like augmented reality device, the augmentations become ubiquitous. This creates the opportunity for new ways of interacting with digital content. However, first we need to know how users interact with these systems to design pleasant user experiences. The view behaviour of users is a core part of their interaction with an any system. Interacting with digital content which is embedded into the real world is bound to change the way users look at the world. We presume that the user’s view behaviour is also influenced by the limited field of view of current generation’s head mounted displays. In these devices, augmentations can only be seen in a limited area in the centre of a user’s visual field. In this thesis, we present a study in which we tested how an augmented reality headset changes the view behaviour. Participants were asked to search for objects in a designated area. They either wore an eye tracker or a head mounted augmented reality display. Afterwards, we compared where participants looked, how long they needed to complete the objective and different aspects of the viewing behaviour, such as height distribution of areas looked at and how fast they moved on average. In general, we found that the head movement while wearing an augmented reality headset resembles the eye movement under normal conditions, although the movements were slower over all. Additionally, completing the search task took longer when participants wore an augmented reality headset. As our study was designed to do fundamental research, these results can not be applied directly on augmented reality application design. However, our results show the existence of effects that can be explored further in future work.

1 version available:

One way to guide them all: Wayfinding strategies and the examination of gender-specific navigational instructions in a real-driving context

Year: 2018

Authors: R Schoedel,S Hilbert,M Bühner,C Stachl

Previous research suggests that men outperform women when they are required to use Euclidean information such as distances for orientation tasks, whereas women are superior in the use of landmarks. Our study examines whether this finding stands up to a test if it is put into an application context. Besides comparing self-reported wayfinding strategies between gender groups, we investigated if auditory instructions in navigation systems can be adjusted to potential gender differences in order to improve performance and to decrease distraction from the driving-task. Participants (N = 76) respond to a questionnaire for wayfinding strategy use and take part in a real-world 20 min, standardized driving task. Driving behavior as well as glance and blink data are recorded via data-logging and eye-tracking. Overall, male and female orientation behavior is much more similar than indicated by previous research. Both men and women predominantly report to use landmark rather than Euclidean information. Correspondingly, even though they selectively respond to distance-versus landmark-based auditory navigational instructions when navigating while driving, the utilization of landmarks as navigation queries results in a lower visual distraction and mental workload for both, men and women. Driving performance is not selectively affected. Our results indicate that the use of landmarks as auditory navigational cues can make driving both safer and more comfortable for men and women. Consequently, in-car navigation systems can benefit from the implementation of landmark navigation prompts.

9 versions available

Perceptual evaluation of synthetic gaze jitter

Year: 2018

Authors: K Krejtz, A Duchowski, H Zhou,S Jörg

Eye movements are an essential part of non-verbal behavior. Non-player characters, as they occur in many games, communicate with the player through dialogue and non-verbal behavior and can have a strong influence on player experience or even on gameplay. In this paper, we evaluate a procedural model designed to synthesize the subtleties of eye motion. More specifically, our model adds microsaccadic jitter and pupil unrest both modeled by 1/f^α or pink noise to the saccadic main sequence. In a series of perceptual two-alternative forced-choice experiments, we explore the perceived naturalness of different parameters of pink noise by comparing synthesized motions to rendered motion of recorded eye movements at extreme close shot and close shot distances. Our results show that, on average, animations based on a procedural model with pink noise were perceived and evaluated as highly natural, whereas data-driven motion without any jitter or with unfiltered jitter were consistently selected as the least natural in appearance.

1 version available:

PERCLOS as an indicator of slow-onset hypoxia in aviation

Year: 2018

Authors: JE Thropp, JFV Scallon, P Buza

BACKGROUND: PERCLOS is a metric that has been primarily studied in the domain of driver fatigue to predict performance decrements, but there is comparatively less research applying it to aviation, where hypoxia is a safety concern. Hypoxic exposure was expected to increase blink activity, possibly by means of impairing blink inhibition behavior, thereby leading to increased eyelid closure time. METHODS: PERCLOS, blink rate, and blink duration were measured using head-mounted eye-tracking on pilots using a flight simulator inside a hypobaric chamber. Pilot subjects were tasked with programming the autopilot of a G-1000 console according to instructions from a simulated air traffic controller. Data was collected at 5% decrements in blood oxygen saturation (S p o 2) through progressive decreases in hypobaric pressure to model slow-onset hypoxia. RESULTS: PERCLOS, blink rate, and blink duration increased significantly and linearly as a function of decreasing S p o 2, and largely recovered in the posthypoxia normoxia condition. The greatest change in PERCLOS relative to the prehypoxia baseline occurred in the 80% S p o 2 condition, whereas the greatest change in blink rate and duration occurred at 75% S p o 2. As S p o 2 decreased, a higher frequency of long blink durations was observed. DISCUSSION: The increase in blink rate and duration in the absence of task demand manipulation could suggest hypoxia-induced sympathetic excitation and impairment of adaptive blink inhibition behavior. The effect of hypoxia on oculomotor features is also likely task-specific. In consideration of the extensive demand made upon the visual modality in flight, increased PERCLOS may further tax visual information processing.

6 versions available

Pre-movement and during-movement visual search behaviours vary depending on expertise and anxiety levels in ten-pin bowling

Year: 2018

Authors: WX Goh, BHY Lim, MJ Wylde

This study investigated the pre-movement and during-movement visual search behaviour (VSB) and quiet eye (QE) of 11 elite versus 10 sub-elite ten-pin bowlers, performing under high-anxiety and low-anxiety conditions. Pre-movement and independent of expertise, bowlers had more fixations and directed them to more locations when performing under high-anxiety compared with low-anxiety. Elite bowlers fixated at more locations closer to the pins in pre-movement than during-movement, with pre-movement QE occurring mostly at the breakpoint and middle arrows. During movement however, bowlers fixated closer to the foul-line at the middle and right dots and arrows, with during-movement-QE occurring at the middle dots and right arrows. Elite bowlers recorded longer QE durations during-movement rather than pre-movement, albeit a later onset during the longish five-step approach prior to ball release compared with sub-elite bowlers. Our results suggest that QE during-movement instead of pre-movement could be more pertinent in differentiating expertise during sporting tasks with a long movement phase and far-aiming target. The relevance of pre-movement or movement-QE in characterising expertise and performance could therefore be sport-dependent. This should be considered when investigating skilled action and developing training programs for skill acquisition.

4 versions available

Predicting and Facilitating the Emergence of Optimal Solutions for a Cooperative “Herding” Task and Testing their Similitude to Contexts Utilizing Full-Body Motion

Year: 2018

Authors: P Nalepka

This study aims to predict and facilitate the emergence of optimal solutions for a cooperative 'herding' task. The utility of such solutions is then tested against contexts requiring full-body motion. The investigation encompasses various methodologies, analyzing the dynamics of cooperative tasks and their resulting effectiveness. By examining these parameters, the study seeks to contribute to the understanding of motion coordination and cooperative behavior, potentially informing fields that require complex motion planning and execution.

4 versions available

Predicting Drivers’ Eyes‐Off‐Road Duration in Different Driving Scenarios

Year: 2018

Authors: W Yuan, Z Liu, R Fu

Drivers consecutively direct their gaze to various areas to select relevant information from the traffic environment. The rate of crash risk increases with different off-road glance durations in different driving scenarios. This paper proposed an approach to identify current driving scenarios and predict driver’s eyes-off-road durations using Hidden Markov Model (HMM). A moving base driving simulator study with 26 participants driving in three driving scenarios (urban, rural, and motorway) was conducted. Three different fixed occlusion durations (0-s, 1-s, and 2-s) were applied to quantify eyes-off-road durations. Participants could initiate each occlusion for certain duration by pressing a microswitch on a finger. They were instructed to occlude their vision as often as possible while still driving safely. Drivers’ visual behavior and occlusion behavior were captured and analyzed based on manually frame by frame coding. Visual behaviors in terms of glance duration and glance location in time series were used as input to train HMMs. The results showed that current driving scenarios could be identified ideally using glance location sequences, the accuracy achieving up to 89.3%. And motorway was relatively distinguishable easily with over 90% accuracy. Moreover, HMM-based algorithms that fed up with both glance duration and glance location sequences resulted in a highest accuracy of 92.7% in driver’s eyes-off-road durations prediction. And higher accuracy achieved in longer eyes-off-road durations prediction. It indicates that time series of glance allocations could be used to predict driving behavior and indentify driving environment. The developed models in this study could contribute to the development of scenario sensitive visual inattention prewarning system.

8 versions available

Preliminary investigation of sleep-related driving fatigue experiment in Indonesia

Year: 2018

Authors: KH Sanjaya, YMK Sya'Bana, S Hutchinson

Sleep-related driving fatigue has been recognized as one of the main causes of traffic accidents. In Indonesia, experiment-based driving fatigue study is still very limited. Therefore it is necessary to develop a laboratory-based experimental procedure for sleep-related fatigue study. In this preliminary study, we performed a literature review to find references for the procedure and three pilot experiments to test the instruments and procedure to be used in measuring driving fatigue. Three subjects participated, both from experienced and inexperienced drivers. Our pilot experiments were performed on a driving simulator using OpenDS software with brake and lane change test reaction time measurement. We measured sleepiness by using Karolinska Sleepiness Scale (KSS) Questionnaire. The conditions of the experiment were based on illumination intensity as well as pre- and post-lunch session. We found that lane change reaction time is more potential than brake reaction time to measure driving performance as shown by more fluctuating data. Post-lunch seems to induce drowsiness greater than illumination intensity. KSS questionnaire seems non-linear with driving performance data. We need to test further these speculations in the future studies involving a sufficient number of subjects. We also need to compare the effect of circadian rhythm and sleep deprivation on driving fatigue. The use of eye closure and physiological measurement in further study will enable us to measure driving fatigue more objectively. Considering the limitations, more preliminary experiments are required to be performed before conducting the main experiment of driving fatigue.

6 versions available

PuRe: Robust pupil detection for real-time pervasive eye tracking

Year: 2018

Authors: T Santini,W Fuhl,E Kasneci

Real-time, accurate, and robust pupil detection is an essential prerequisite to enable pervasive eye-tracking and its applications – e.g., gaze-based human computer interaction, health monitoring, foveated rendering, and advanced driver assistance. However, automated pupil detection has proved to be an intricate task in real-world scenarios due to a large mixture of challenges such as quickly changing illumination and occlusions. In this paper, we introduce the Pupil Reconstructor (PuRe), a method for pupil detection in pervasive scenarios based on a novel edge segment selection and conditional segment combination schemes; the method also includes a confidence measure for the detected pupil. The proposed method was evaluated on over 316,000 images acquired with four distinct head-mounted eye tracking devices. Results show a pupil detection rate improvement of over 10 percentage points w.r.t. state-of-the-art algorithms in the two most challenging data sets (6.46 for all data sets), further pushing the envelope for pupil detection. Moreover, we advance the evaluation protocol of pupil detection algorithms by also considering eye images in which pupils are not present and contributing a new data set of mostly closed eyes images. In this aspect, PuRe improved precision and specificity w.r.t. state-of-the-art algorithms by 25.05 and 10.94 percentage points, respectively, demonstrating the meaningfulness of PuRe’s confidence measure. PuRe operates in real-time for modern eye trackers (at 120 fps) and is fully integrated into EyeRecToo – an open-source state-of-the-art software for pervasive head-mounted eye tracking.

9 versions available