72 research outputs found

    Using operational scenarios in a virtual reality enhanced design process

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    Maritime user interfaces for ships’ bridges are highly dependent on the context in which they are used, and rich maritime context is difficult to recreate in the early stages of user-centered design processes. Operations in Arctic waters where crews are faced with extreme environmental conditions, technology limitations and a lack of accurate navigational information further increase this challenge. There is a lack of research supporting the user-centered design of workplaces for hazardous Arctic operations. To meet this challenge, this paper reports on the process of developing virtual reality-reconstructed operational scenarios to connect stakeholders, end-users, designers, and human factors specialists in a joint process. This paper explores how virtual reality-reconstructed operational scenarios can be used as a tool both for concept development and user testing. Three operational scenarios were developed, implemented in a full mission bridge simulator, recreated in virtual reality (VR), and finally tested on navigators (end-users). Qualitative data were captured throughout the design process and user-testing, resulting in a thematic analysis that identified common themes reflecting the experiences gained throughout this process. In conclusion, we argue that operational scenarios, rendered in immersive media such as VR, may be an important and reusable asset when supporting maritime design processes and in maritime training and education

    Eye Tracking during High Speed Navigation at Sea

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    Purpose: Professional high speed sea navigational procedures are based on turn points, courses, dangers and steering cues in the environment. Since navigational aids have become less expensive and due to the fact that electronic sea charts can be integrated with both radar and transponder information, it may be assumed that traditional navigation by using paper based charts and radar will play a less significant role in the future, especially among less experienced navigators. Possible navigational differences between experienced and non-experienced boat drivers is thus of interest with regards to their use of navigational aids. It may be assumed that less experienced navigators rely too much on the information given by the electronic sea chart, despite the fact that it is based on GPS information that can be questioned, especially in littoral waters close to land.Method: This eye tracking study investigates gaze behaviour from 16 experienced and novice boat drivers during high speed navigation at sea.Results: The results show that the novice drivers look at objects that are close to themselves, like instrumentation, while the experienced look more at objects far away from the boat. This is in accordance with previous research on car drivers. Further, novice boat drivers used the electronic navigational aids to a larger extent than the experienced, especially during high speed conditions. The experienced drivers focused much of their attention on objects outside the boat.Conclusions: The findings verify that novice boat drivers tend to rely on electronic navigational aids. Experienced drivers presumably use the navigational aids to verify what they have observed in the surrounding environment and further use the paper based sea chart to a larger extent than the novice drivers

    Teenage outcomes after speech and language impairment at preschool age

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    Ulla Ek1, Fritjof Norrelgen3,4, Joakim Westerlund2, Andrea Dahlman5, Elizabeth Hultby5, Elisabeth Fernell61Department of Special Education, 2Department of Psychology, Stockholm University, Stockholm, Sweden; 3Department of Speech and Language Pathology, Karolinska University Hospital, Stockholm, Sweden; 4Department of Clinical Neuroscience, 5CLINTEC/Division of Speech and Language Pathology, Karolinska Institutet, Stockholm, Sweden; 6The Gillberg Neuropsychiatry Centre, Sahlgrenska Academy, University of Gothenburg and the Research and Development Centre, Skaraborg Hospital, Skövde, SwedenAim: Ten years ago, we published developmental data on a representative group of children (n = 25) with moderate or severe speech and language impairment, who were attending special preschools for children. The aim of this study was to perform a follow-up of these children as teenagers.Methods: Parents of 23 teenagers participated in a clinical interview that requested information on the child's current academic achievement, type of school, previous clinical assessments, and developmental diagnoses. Fifteen children participated in a speech and language evaluation, and 13 participated in a psychological evaluation.Results: Seven of the 23 teenagers had a mild intellectual disability, and another three had borderline intellectual functioning. Nine had symptoms of disorders on the autism spectrum; five of these had an autism spectrum disorder, and four had clear autistic traits. Six met criteria for attention-deficit hyperactivity disorder (ADHD)/subthreshold ADHD. Thirteen of 15 teenagers had a moderate or severe language impairment, and 13 of 15 had a moderate or severe reading impairment. Overlapping disorders were frequent. None of the individuals who underwent the clinical evaluation were free from developmental problems.Conclusion: A large number of children with speech and language impairment at preschool age had persistent language problems and/or met the criteria for developmental diagnoses other than speech and language impairment at their follow-up as teenagers. Language impairment in young children is a marker for several developmental disorders, particularly intellectual disability and autism spectrum disorder.Keywords: language impairment, dyslexia, developmental disorders, autism spectrum disorder, ADHD, follow-u

    Could sound be used as a strategy for reducing symptoms of perceived motion sickness?

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    <p>Abstract</p> <p>Background</p> <p>Working while exposed to motions, physically and psychologically affects a person. Traditionally, motion sickness symptom reduction has implied use of medication, which can lead to detrimental effects on performance. Non-pharmaceutical strategies, in turn, often require cognitive and perceptual attention. Hence, for people working in high demand environments where it is impossible to reallocate focus of attention, other strategies are called upon. The aim of the study was to investigate possible impact of a mitigation strategy on perceived motion sickness and psychophysiological responses, based on an artificial sound horizon compared with a non-positioned sound source.</p> <p>Methods</p> <p>Twenty-three healthy subjects were seated on a motion platform in an artificial sound horizon or in non-positioned sound, in random order with one week interval between the trials. Perceived motion sickness (Mal), maximum duration of exposure (ST), skin conductance, blood volume pulse, temperature, respiration rate, eye movements and heart rate were measured continuously throughout the trials.</p> <p>Results</p> <p>Mal scores increased over time in both sound conditions, but the artificial sound horizon, applied as a mitigation strategy for perceived motion sickness, showed no significant effect on Mal scores or ST. The number of fixations increased with time in the non-positioned sound condition. Moreover, fixation time was longer in the non-positioned sound condition compared with sound horizon, indicating that the subjects used more time to fixate and, hence, assumingly made fewer saccades.</p> <p>Conclusion</p> <p>A subliminally presented artificial sound horizon did not significantly affect perceived motion sickness, psychophysiological variables or the time the subjects endured the motion sickness triggering stimuli. The number of fixations and fixation times increased over time in the non-positioned sound condition.</p

    Usability of the SAFEWAY@SCHOOL system in children with cognitive disabilities

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    PurposeSAFEWAY2SCHOOL is a programme based on several systems for the enhancement of school transportation safety for children. The aim of the study was to explore whether children with cognitive disabilities will notice, realise, understand, trust and accept the SAFEWAY2SCHOOL system and act in accordance with its instructions. Methods Fourteen children with cognitive disabilities and a control group of 23 children were shown five videos of scenarios involving journeys to and from school. During the first viewing visual scanning patterns were recorded with an eye tracking device. After a second viewing the participant was asked ten questions per scenario. Five questions addressed what the children saw on the video, and the remaining five what they would need to know and/or do within the scenario. Additional ratings of trust, likability, acceptability and usability were also collected. Results Very few differences were found in the visual scanning patterns of children with disabilities compared to children who participated in the control group. Of the 50 questions regarding what children saw or needed to know and/or do, only one significant difference between groups was found. No significant differences were found regarding self-reported ratings of trust, acceptability or usability of the system. Despite some significant differences across five of the 11 likability aspects, ratings were consistently high for both groups. Conclusions Children with cognitive disabilities proved that the SAFEWAY2SCHOOL system is as useful for them as it was for children in the control group. However, a valid estimation of the full utility of SAFEWAY2SCHOOL requires in situ testing of the system with these children

    Physiological responses to low-force work and psychosocial stress in women with chronic trapezius myalgia

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    <p>Abstract</p> <p>Background</p> <p>Repetitive and stressful work tasks have been linked to the development of pain in the trapezius muscle, although the underlying mechanisms still remain unclear. In earlier studies, it has been hypothesized that chronic muscle pain conditions are associated with imbalance in the autonomic nervous system, predominantly expressed as an increased sympathetic activity. This study investigates whether women with chronic trapezius myalgia show higher muscle activity and increased sympathetic tone at baseline and during repetitive low-force work and psychosocial stress, compared with pain-free controls.</p> <p>Methods</p> <p>Eighteen women with chronic trapezius myalgia (MYA) and 30 healthy female controls (CON) were studied during baseline rest, 100 min of repetitive low-force work, 20 min of psychosocial stress (Trier Social Stress Test, TSST), and 80 min recovery. The subjects rated their pain intensity, stress and energy level every 20 min throughout the experiment. Muscle activity was measured by surface electromyography in the trapezius muscle (EMGtrap) and deltoid muscle (EMGdelt). Autonomic reactivity was measured through heart rate (HR), skin conductance (SCL), blood pressure (MAP) and respiration rate (Resp).</p> <p>Results</p> <p>At baseline, EMGtrap, stress ratings, and HR were higher in MYA than in CON. Energy ratings, EMGdelt, SCL, MAP and Resp were, however, similar in the two groups. Significant main group effects were found for pain intensity, stress ratings and EMGtrap. Deltoid muscle activity and autonomic responses were almost identical in MYA and CON during work, stress and recovery. In MYA only, pain intensity and stress ratings increased towards the end of the repetitive work.</p> <p>Conclusion</p> <p>We found increased muscle activity during uninstructed rest in the painful muscle of a group of women with trapezius myalgia. The present study could not confirm the hypothesis that chronic trapezius myalgia is associated with increased sympathetic activity. The suggestion of autonomic imbalance in patients with chronic local or regional musculoskeletal pain needs to be further investigated.</p

    Väntetider vid plankorsningar - upplevda och faktiska : en litteraturstudie

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    Rörelsesjuka, ingen sjukdom men väl en naturlig respons i en onaturlig miljö!

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    Motion sickness is not an illness, but rather a natural autonomic response to an unfamiliar or specific stimulus. The bodily responses to motion sickness are highly individual and contextually dependent, making them difficult to predict. The initial autonomic responses are similar to the ones demonstrated when under stress. When under the influence of motion sickness, motivation and ability to perform tasks or duties are limited. However, little is known about how specific cognitive functions are affected. Furthermore, standard mitigation strategies involve medications that induce fatigue or strategies that require cognitive capabilities. Both of them may result in reduced capability to perform assigned tasks or duties. Hence, there is a need for alternative mitigation strategies. The aim of the thesis was to study psychophysiological and performance aspects on motion sickness. The long-term goal is to provide strategies for mitigation and prevention of motion sickness by identifying psychophysiological responses as predictors for both wellbeing and performance. This thesis comprises four studies, in which 91 participants were exposed to two different motion sickness stimuli, either an optokinetic drum or a motion platform. Before the tests, a method for extracting fixations from eye-tracking data was developed as a prerequisite for studying fixations as a possible mitigation strategy for reducing motion sickness. During exposure to stimuli that triggers motion sickness, performance was studied by testing short-term memory and encoding and retrieval. In the final study, the effects of an artificial sound horizon were studied with respect to its potential to subconsciously function as a mitigating source. The results of the measurements of the psychophysiological responses were in accordance with previous research, confirming the ambiguity and high individuality of the responses as well as their contextual dependencies. To study fixations, a centroid mode algorithm proved to be the best way to generate fixations from eye-movement data. In the final study, the effects of the sound horizon were compared to the effects of a non-positioned sound. In the latter condition, both fixation time and the number of fixations increased over time, whereas none of them showed a significant time effect in the sound horizon condition. The fixation time slope was significantly larger in the non-positioned sound condition compared to the sound horizon condition. Number of fixations, heart rate, and skin conductance correlated positively with subjective statements that referred to motion sickness. Among participants that were susceptible to motion sickness symptoms, short-term memory performance was negatively affected. However, no effects of motion sickness on encoding and retrieval were found, regardless of susceptibility. Future studies should continue focusing on autonomic responses and psychological issues of motion sickness. Factors such as motivation, expectancies, and previous experiences play a major and yet relatively unknown role within the motion sickness phenomena
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